Metrics details Ceramics and single crystals of LaPO4 monazite doped with Eu(III) were irradiated with 14 MeV Au5+ ions at three different fluences and topography were probed using grazing-incidence X-ray diffraction (GIXRD) GIXRD data of the ceramics revealed fluence dependent amorphization A similar level of amorphization was detected for samples irradiated with 5 × 1013 ions/cm2 and 1 × 1014 ions/cm2 whereas the sample irradiated with the highest fluence of 1 × 1015 ions/cm2 appeared slightly less amorphous VSI showed clear swelling of entire grains at the highest ion fluence while more localized damage to grain boundaries was detected for ceramic samples irradiated at the lowest fluence Single crystal specimens showed no pronounced topography changes following irradiation SEM images of the ceramic irradiated at the highest fluence showed topological features indicative of grain surface melting Raman and luminescence data showed a different degree of disorder in polycrystalline vs While changes to PO4 vibrational modes were observed in the ceramics changes were more subtle or not present in the single crystals The opposite was observed when probing the local Ln-O environment using Eu(III) luminescence where the larger changes in terms of an elongation of the Eu-O (or La-O) bond and an increasing relative disorder with increasing fluence were observed only for the single crystals The dissimilar trends observed in irradiated single crystals and ceramics indicate that grain boundary chemistry likely plays a significant role in the radiation response a different radiation response of polycrystalline samples and single crystals can be expected there is a dearth of studies that focus on how polycrystalline samples and single crystals of the same chemical composition differ in their response to radiation ceramics and single crystals were doped with Eu(III) as a luminescent probe to allow for a local structural analysis by luminescence spectroscopy By irradiating ceramics and single crystals of the same composition under identical conditions we examined the dependence of the response to the irradiation on sample form both in the presence and absence of grain boundaries A depth of approximately two micrometers was calculated and considered when performing all analyses of the irradiated samples Diffraction data of the LaPO4 sample irradiated at F2 (a); sample irradiated at F3 (b); and comparison of the integrated data for samples irradiated at all fluences at incident angle α = 1° (c) a Scattering from the sample irradiated at F1 featuring structured diffuse scattering on top of broad diffuse signal. b Scattering from the sample irradiated at F2 showing only broad diffuse signal. Normalized qualitative amorphous scattering signal from the irradiated LaPO4 ceramic samples low-r part of pair distribution function (a) obtained from the ceramic irradiated at F3 scattering data (b) F3 irradiated sample is shown as an example) and they correspond to scattering pairs with c.a The origin of these correlations can be determined by examining the three-dimensional crystal structure of the parent crystalline LaPO4 phase the presence of peaks on the G(r) function at 2.5 and 6.7 Å indicates the preservation of the LaO9 polyhedra and stronger structural rigidity along the a axis which is the direction of edge sharing LaO9 and PO4 units stacking of the LaO9-PO4 chains is also correlated by a 4.3 Å peak on the experimental PDF analysis Since the sample irradiated at the F1 fluence possesses additional features on top of the base diffuse signal observed for the higher F2 or F3 irradiated samples the lower fluence induces smaller structural damage in LaPO4 indicate better preservation of the LaO9 structural units which feature nine independent La-O distances in the parent crystalline LaPO4 the corresponding fine details cannot be obtained from the limited scattering data of the F1 irradiated sample VSI images of LaPO4 monazite ceramics exposed to F1 (a) and F3 (b) and of single crystals without irradiation (c) and exposed to F3 (d) SEM images of irradiated LaPO4 ceramics the surface of ceramic irradiated at F3 (a) the irradiated-pristine boundary of the ceramic irradiated at F3 (b) the irradiated-pristine boundary the ceramic irradiated at F1 (e) This corroborates signs of recrystallization observed in the LaPO4 ceramic irradiated at the highest fluence this phenomenon was not observed in the other two monazite ceramics irradiated at lower fluences This could explain the difference in spectroscopic results between the irradiated monazite single crystals and ceramics discussed in the following section Raman spectra of pristine and irradiated LaPO4 monazite ceramics (a) and single crystals (b) Raman spectra normalized to the ν1 band intensity (lower wavenumber region) of the irradiated LaPO4 monazite ceramics (a) and single crystals (b) It is worth noting that Raman spectra of irradiated monazites appear dependent on a number of factors type of irradiation (self-irradiation versus external ion-irradiation) and the setup of the Raman instrument as confocal or non-confocal It is important to note that luminescent probes still give a spectrum even when in amorphous environments making it well-suited for a sample in which irradiation-induced amorphization is likely to occur Eu(III) excitation spectra (7F0 ← 5D0 transition) of LaPO4 monazites doped with 500 ppm Eu(III): polycrystalline ceramics (a) and single crystals (b) Emission spectra of irradiated LaPO4 monazite ceramics (a) and single crystals (b) doped with 500 ppm Eu(III) Trends in the 7F2/7F1 ratios of emission spectra collected after excitation at the peak maximum and at the full width at half maximum of the integrated excitation peaks for the ceramics (a) and the single crystals (b) the lifetimes of the samples do not provide additional information about their microstructure specifically with regard to radiation damage ion-irradiated LaPO4 monazite ceramics and single crystals have been investigated with a combination of diffraction GIXRD data indicated a non-systematic amorphization of the ceramic surface with increasing ion fluence The extracted reduced signal from the amorphized part of the irradiated LaPO4 samples featured near identical diffuse signals characterized by two broad peaks around 20 and 30° 2θ Detailed information about the short-range order correlations in the sample was obtained from the calculated PDF Three dominant interatomic distances at ~2.5 corresponding to average La-O and La-La distances along the c and a directions in the monazite structure clearly showing that short-range order is retained in the amorphous material VSI and SEM data showed different types of topographical and microstructural damage at the different fluences localized damage at the grain boundaries of the ceramic pellet was evidenced while an increasing fluence resulted in additional grain break out and even softened grains with rounded edges indicative of grain melting or partial recrystallization of the ceramic surface showed no topological features following irradiation attributed to the lack of grain boundaries in the samples Raman spectroscopy probing phosphate vibrations in the samples and Eu(III) luminescence spectroscopy addressing the Ln-O environment in the monazites were conducted for the ceramic pellets and single crystal specimens to understand the relative radiation response of the different sample types In the Raman spectra of irradiated ceramic samples and single crystals a shoulder on the symmetric stretch vibration at ~960 cm–1 was visible swollen grains showed a larger contribution of the shoulder at 960 cm–1 than smooth surfaces while grain boundary regions showed featureless spectra indicative for amorphization which speaks for a heterogeneous damage distribution in the ceramics no differences in the Raman data collected at different regions on the single crystals were seen implying a more homogenous overall damage in these specimens The Eu(III) luminescence data collected for the ceramic samples were almost identical for all fluences Very small changes in the excitation peak position and the 7F2/7F1 band ratio could be seen for fluences F1 and F2 while spectra collected for F3were almost identical to the pristine sample a subtle but systematic blue-shift of the excitation peak signal was seen following an increased interatomic distance between the Eu (La) atoms and the coordinating oxygen atoms with increasing fluence The increasing bond distance was accompanied by a systematic increase of the 7F2/7F1 band ratio suggesting an increasing asymmetry in the samples The results of this study clearly show that single crystals and ceramics react differently to heavy ion irradiation While fluence F3 shows large microstructural changes diffraction and spectroscopic data suggest partial recrystallization of the sample and a heterogeneous damage distribution localized at grain boundaries As reason for the different damage response of the polycrystalline samples and single crystals we postulate partial beam-induced annealing of the radiation damage enabled by grain boundaries where defect recombination can take place defect annealing appears to apply mainly to the La-O environment probed via luminescence spectroscopy where no changes to the EuO9 (LaO9) polyhedron could be observed at the highest fluence Raman data show amorphous regions at grain boundaries and larger damage to swollen grains than at smooth surfaces which would imply that similar annealing of the covalent P–O network does not take place to the same extent additional studies targeting annealing mechanisms in irradiated solids are required for an in-depth understanding of the damage-recovery pathways in the monazite LnO9 and PO4 polyhedra in which the implantation ions have significantly higher energies and therefore penetrate deeper into the sample could be beneficial to avoid contributions from the pristine layers of the sample during analyses structural damage such as amorphization and bond elongation will be more readily observed in diffraction and spectroscopic data this study underlines the necessity to consider the correct sample type and design when investigating irradiation damages of materials for nuclear waste disposal irradiation results obtained for single crystals are not necessarily directly transferable to ceramic specimens always be included in irradiation studies to understand the radiation response of a ceramic waste form in high radiation fields The appropriate amounts of La(NO3)3.6H2O and Eu(NO3)3.6H2O were weighed out gravimetrically and then dissolved in millipure H2O with a resistivity of 18 MΩ H3PO4 was then added in excess to this solution with stirring and a white precipitate formed the dilute acid was decanted off and the solid was transferred to an alumina crucible and dried in a furnace for three hours at 120 °C Green pellets were placed in alumina crucibles and sintered at 1400 °C in air for four to five hours using a ramp rate of 4 °C/min and a cooling rate of 6 °C/min LaPO4 single crystals were synthesized by a high-temperature solution (flux) method The molar ratio of the flux components was 75:25:2 ≡ MoO3:Li2CO3:LaPO4 Homogeneity of the flux was ensured by holding the solution at 1173 K for 12 h before raising the temperature to 1623 K for complete dissolution of the monazite powder and subsequent cooling to 1143 K with 2 K/h for single crystal growth the crucibles were removed from the furnace and cooled in air The single crystals were extracted by dissolving the flux in water in an ultrasonic bath All experiments were carried out in closed platinum crucibles During data collection studied here monazite samples were rotated by 20° in order to improve peak shape and statistics of samples with coarse grain structure VSI data were obtained by means of an S Neox 3D Optical Profiler (Sensofar Spain) with 10× and 100× Mirau objectives (1.3 and 0.13 µm/pixel The topography datasets were processed using the imaging software SPIP (version 6.7.4 samples were not sputtered or treated before analysis Microstructural characterization was performed by SEM and EDS (FESEM Gemini 500 Acceleration voltages of 1 kV yielded high-quality secondary electron images without surface charging backscattered images had to be taken at 15 kV in the variable pressure mode The reduced vacuum allows charge equalization at the surface by the gas molecules Raman spectra were collected on a Horiba Jobin Yvon Raman spectrometer equipped with an Olympus BX41 optical microscope in a non-confocal setup Spectra were obtained using a He/Ne laser (λ = 633 nm) excitation source Typical parameters for the collection of spectra included 20 s acquisition time and 10 accumulations over the range of 70–1200 cm–1 Background corrections and peak fitting were conducted using the OriginPro software package A pseudo-Voigt fitting scheme was used to determine the peak centers and FWHM values To achieve the required spectra resolution solid samples were cooled to ~10 K in a helium-refrigerated cryostat TRLFS for the collection of Eu(III) excitation and emission spectra was performed with a pulsed Nd:YAG (Continuum Surelite) pumped dye laser setup (Radiant Dyes Narrow Scan K) by directly exciting the Eu(III) ion from the ground state (7F0) to the emitting state (5D0) The emitted luminescence was directed into an optical multichannel analyzer (Shamrock 303i) with a 1200 lines/millimeter grating and the emission was detected with an intensified CCD camera (iStar and 5 ms after the exciting laser pulse in a time window of 10 ms The laser pulse energy and the exact excitation wavelength were monitored with an optical power meter (Newport 1918-R) and a wavelength meter (High Finesse WS-5) Excitation Spectra were integrated over the F2 band and normalized to allow for comparisons in peak center and FWHM The datasets from this study are available from the authors upon reasonable request Crystal chemistry of the monazite structure Rare earth minerals and resources in the world Versatile Monazite: Resolving geological records and solving challenges in materials science Monazite as a promising long-term radioactive waste matrix: Benefits of high-structural flexibility and chemical durability Crystal chemistry of the monazite and xenotime structures Incorporation of thorium in the rhabdophane structure: synthesis and characterization of Pr1-2xCaxThxPO4·nH2O solid solutions The absence of metamictisation in natural monazite Uranium- and thorium-rich monazite from a south-alpine pegmatite at Piona Displacive radiation effects in the monazite- and zircon-structure orthophosphates Radiation effects in crystalline ceramics for the immobilization of high-level nuclear waste and plutonium A Raman spectroscopic study on the structural disorder of monazite–(Ce) Swelling induced by alpha decay in monazite and zirconolite ceramics: A XRD and TEM comparative study Probing the effect of radiation damage on the structure of rare-earth phosphates Irradiation effects in monazite-(Ce) and zircon: Raman and photoluminescence study of Au-irradiated FIB foils Self-irradiation of monazite ceramics: contrasting behavior of PuPO4 and (La,Pu)PO4 doped with Pu-238 Plutonium and americium monazite materials: solid state synthesis and X-ray diffraction study Interplay between grain boundaries and radiation damage Size dependence of radiation-induced amorphization and recrystallization of synthetic nanostructured CePO4 monazite Radiation tolerance of nanocrystalline ceramics: insights from yttria stabilized zirconia The multiple roles of small-angle tilt grain boundaries in annihilating radiation damage in SiC Radiation damage in diopside and calcite crystals from uranothorianite inclusions Irradiation damage in monazite-(Ce): an example to establish the limits of raman confocality and depth resolution Raman spectra of the rare earth orthophosphates Vibrational spectra of monazite-type rare-earth orthophosphates SRIM – The stopping and range of ions in matter (2010) On the use of SRIM for computing radiation damage exposure Revisiting the thermal-spike concept in ion-surface interactions Grain growth and phase stability of nanocrystalline cubic zirconia under ion irradiation Mechanism of the monoclinic-to-tetragonal phase transition induced in zirconia and hafnia by swift heavy ions JGIXA — A software package for the calculation and fitting of grazing incidence X-ray fluorescence and X-ray reflectivity data for the characterization of nanometer-layers and ultra-shallow-implants ROBL-II at ESRF: a synchrotron toolbox for actinide research Grazing-incidence synchrotron radiation diffraction studies on irradiated Ce-doped and pristine Y-stabilized ZrO2 at the Rossendorf beamline PDFgetX3: a rapid and highly automatable program for processing powder diffraction data into total scattering pair distribution functions Direct measurement of surface dissolution rates in potential nuclear waste forms: the example of pyrochlore Variability of crystal surface reactivity: what do we know Ion irradiation and modification: the role of coupled electronic and nuclear energy dissipation and subsequent nonequilibrium processes in materials Grain size effect on the radiation damage tolerance of cubic zirconia against simultaneous low and high energy heavy ions: nano triumphs bulk and internal stress optically evaluated by micro-Raman spectroscopy Structural and vibrational analyses of CePO4 synthetic monazite samples under an optimized precipitation process Using Eu3+ as an atomic probe to investigate the local environment in LaPO4–GdPO4 monazite end-members Probing structural homogeneity of La1-xGdxPO4 monazite-type solid solutions by combined spectroscopic and computational studies Radiation-induced segregation in a ceramic sinterability and mechanical properties of La-monazite-type ceramics a versatile library for azimuthal regrouping DIOPTAS: a program for reduction of two-dimensional X-ray diffraction data and data exploration Download references We acknowledge the use of the Ion Beam Center HZDR for irradiations and the use of ROBL for GIXD measurements We gratefully acknowledge the BMBF for funding through grant number 02NUK060 Open Access funding enabled and organized by Projekt DEAL Institute of Fusion Energy and Nuclear Waste Management (IFN-2) funding acquisition; T.T.: review; L.P.: review and editing; C.F.: methodology The authors declare no competing interests Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations Supplementary Information for: Microstructural Investigation of Au Ion-Irradiated Eu-Doped LaPO₄ Ceramics and Single Crystals Download citation DOI: https://doi.org/10.1038/s41529-024-00504-3 Anyone you share the following link with will be able to read this content: Sorry, a shareable link is not currently available for this article. 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SuomeksiTampere university / Tampere university of applied sciencesSearchMenuTuni.fi›News›Our alumna Noora Hyttinen: I want to be part of developing a sustainable and humane working lifePeopleOur alumna Noora Hyttinen: I want to be part of developing a sustainable and humane working lifePublished on 16.4.2025Tampere University of Applied SciencesPhoto: Sanni HujanenPhoto: Sanni HujanenNoora Hyttinen an alumna of Tampere University of Applied Sciences Proakatemia works as an entrepreneur and dialogue coach in Kasvussa Oy a company she founded together with her business partner Jussi Haavisto The company's mission is to build a sustainable and humane working life in Finland Hyttinen was awarded a scholarship to participate in the Tiimiakatemia Global Oy's Tiimiimestari® training The same training was also attended by Jussi Haavisto who had already experienced one career as a marketing consultant they ended up sharing the same journey to the coaching sessions.  - During the trips we got to know each other better and quickly noticed that we had very similar ideas about working life and its challenges We also shared the same passion for developing working life through dialogue and coaching.  and Kasvussa Oy was founded immediately after Hyttinen's graduation in January 2024.  Originally from a North Karelian town of Liperi Hyttinen taught partner dancing through her own company.  She studied partner dance coaching in Huittinen from where her journey continued to Tampere after a year I applied to study at Proakatemia to deepen my entrepreneurial skills I was particularly attracted by the practical side of my studies and learning by trying together as a team.  Hyttinen got into Proakatemia on her second attempt the entrance exam left a strong impression of the sense of community that exists at Proakatemia where the team met twice a week to discuss were also important for Hyttinen in finding her own way.  I was still thinking about continuing my dance business I also had dreams of opening my own dance school during my studies I developed a passion for development and dialogue Studies at Proakatemia gave Hyttinen a new direction and the couple dance coach turned into a dialogue coach for work communities Proakatemia is known for its lively alumni activities and according to Hyttinen there is a close contact between former and current students.  I want to share my expertise and also serve as an inspiration to students about what it is like to work as an entrepreneur with their own strengths and values building bridges between working life and studies is central to alumni activities This is something she also wants to promote through her own company Kasvussa Oy is one of the corporate partners of the HUBS Sprint Innovation Festival in March which offers entrepreneurship studies for students at Tampere universities.  Continuous learning and development was important to Hyttinen already during her studies building networks and working together with different people are also topics that she wants to emphasise to current and future university students.  - It is worth being curious and giving yourself a chance to achieve something together with others that you could not even think of yourself The company has now been in operation for a year the partners refined the focus of the business and it has paid off.  - We both realised that we wanted to focus specifically on dialogue and long-term development as we have already been able to do long-term work with companies such as Lerøy Finland which wholesales and retails fish products and the confectionery company Cloetta.  The development of our own company is also supported by an advisory board whose members were recruited from the Future Board network of young government experts Hyttinen not only wants to help her clients grow - I want to be part of the change and contribute to the Finnish working life we want to make Kasvussa Oy a significant player in the development of Finnish working life Degree Program in Entrepreneurship and Team Leadership Work: Entrepreneur and dialogy coach at Kasvussa Oy  Leisure time: As a former couples dance coach, exercise is still an important life-balancing factor for an entrepreneur. 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Our areas of priority in research and education are technology, health and society.Tampere University: +358 (0)294 5211Tampere University of Applied Sciences : +358 (0)294 5222 Open image viewerTiia Tuulia Juurmaa covered her face with an Aku Ankka (Donald Duck) comic during the trial Image: Roni Lehti / AFPYle News12.11.2024 14:15•Updated 12.11.2024 14:19A court on Tuesday handed down a three-year prison sentence to a young woman who last autumn kidnapped a seven-day-old baby in Huittinen received a sentence for aggravated assault She was also ordered to be incarcerated immediately Earlier this year Satakunta District Court ordered Juurmaa found that Juurmaa was of sound mind when committing the act The assault and kidnapping occurred in September 2023 met up in the centre of Huittinen to go for a walk Juurmaa falsely claimed that she had recently given birth and suggested the meetup to the victim through a social media group Juurmaa showed up for the date carrying a doll in a baby carrier Juurmaa hit the victim over the head with a hammer before abducting her newborn baby she told them she could temporarily take the baby to her home to keep the child safe she kidnapped the newborn and jumped on a Helsinki-bound bus for which she had purchased a ticket in advance The fraud conviction pertains to Juurmaa deceiving a man she knew into believing that he had fathered a child She had sent this man hundreds of messages Juurmaa had also suggested to the man that they move to the city of Lappeenranta The man had believed the story and even agreed to the move He also offered to pick Juurmaa and the child up from the hospital had purchased baby supplies as well as booked a hotel room in Helsinki The Satakunta District Court's ruling is subject to appeal meaning it could still be appealed to a higher court The dates displayed for an article provide information on when various publication milestones were reached at the journal that has published the article activities on preceding journals at which the article was previously under consideration are not shown (for instance submission Science of the Total EnvironmentCitation Excerpt :Researchers have discovered that the existence of these colloids can impact the movement of radionuclides in geological materials (Albarran et al. bentonite colloids can intensify the absorption of Sr by claystone when exposed to alkaline conditions (Philipp et al. humic acid (HA) can significantly increase Eu(III) sorption on Na-bentonite colloids (Hu et al. All content on this site: Copyright © 2025 Elsevier B.V. is acting as a test bed for new ideas that could help the city reach a goal of becoming carbon-neutral by 2030 By Adam Vaughan A neighbourhood in the shadow of a coal power station on the outskirts of Helsinki might seem an unlikely place to evangelise about its environmental credentials But here in the former cargo port of Kalasatama a 31-year mega project is under way to build a model green urban district that should eventually be home to 30,000 people “It’s getting better and better by the day,” says Hetta Huittinen-Naskali who has lived in Kalasatama for four years Metrics details Nuclear energy provides a widely applied carbon-reduced energy source containing a mixture of radiotoxic elements such as transuranics Safe storage of SNF in a deep geological repository (DGR) relies on multiple engineered and natural retention barriers to prevent environmental contamination zirconia (ZrO2) formed on the SNF rod cladding could be employed as an engineered barrier for immobilization of radionuclides via structural incorporation This study investigates the incorporation of Eu3+ and Cm3+ representatives for trivalent transuranics into zirconia by co-precipitation and crystallization in aqueous solution at 80 °C Complementary structural and microstructural characterization has been carried out by powder X-ray diffraction (PXRD) spectrum imaging analysis based on energy-dispersive X-ray spectroscopy in scanning transmission electron microscopy mode (STEM-EDXS) The results reveal the association of the dopants with the zirconia particles and elucidate the presence of distinct bulk and superficially incorporated species Hydrothermal aging for up to 460 days in alkaline media points to great stability of these incorporated species after initial crystallization with no indication of phase segregation or release of Eu3+ and Cm3+ over time These results suggest that zirconia would be a suitable technical retention barrier for mobilized trivalent actinides in a DGR Incorporation of subvalent cations is accompanied by oxygen vacancy formation in the host structure to retain charge neutrality These vacancies will thereby reduce the coordination number of the cations in the structure The incorporation of subvalent dopants in ZrO2 has been extensively studied using high-temperature (1000–1500 °C) synthesis methods including co-precipitation or solid-state reaction routes yielding a crystalline Much less is known about the uptake mechanism of subvalent cations into the ZrO2 crystal structure during crystallization in aqueous solution in the context of nuclear waste management on determining the stability of the undoped tetragonal zirconia particles ultimately resulting in a critical crystallite size upon which the free energy favors the thermodynamically more stable monoclinic phase Some of the investigated parameters included the surface energy strain energies and multiple other effects that play into the stability range of this phase The critical crystallite size for the tetragonal structure to be thermodynamically stable was estimated to be in a range between 10 and 33 nm The experiments are designed to study the influence of the dopants and the hydrothermal aging time on the incorporation mechanism The two studied dopants have been chosen due to their + 3 oxidation state being the most stable one in the aqueous phase and their excellent luminescence properties making it possible to study their coordination environment via luminescence spectroscopy Powder X-ray diffraction (PXRD) and spectrum imaging analysis based on energy-dispersive X-ray spectroscopy in scanning transmission electron microscopy mode (STEM-EDXS) provide further insights into the phase composition and the spatial distribution of the elements in the ZrO2 structure Phase composition of the ZrO2 samples containing 500 ppm Eu3+ (a) with the monoclinic phase depicted in squares (black) the tetragonal and cubic phase in circles (red) and the overall crystallinity of the Eu3+-doped samples shown as triangles (blue) determined with Si as internal standard The crystallite size of all samples was determined using the Debye–Scherrer Eq. (1) and is given in Table 1 A slight increase of the crystallite size can be seen with increasing hydrothermal treatment time for all dopants and concentrations The different ZrO2 polymorphs and the chosen dopant concentrations do not have a significant effect on the crystallite size the crystallite size seems to be independent on the dopant element considering the similar crystallite sizes for the Eu- and Cm-doped ZrO2 STEM-based analysis for the Eu:ZrO2 samples containing 1 mol% dopant after 32 days (A–D) and 399 days (E–H) of thermal treatment time H) show the corresponding superimposed EDXS-based element distribution maps for Zr (blue) Luminescence emission spectra of the Cm:ZrO2 samples containing 30 ppm Cm3+ (a) and the Eu:ZrO2 samples containing 1 mol% Eu3+ (b) The Cm3+ spectra are normalized to the area under the curve while the Eu3+ spectra are normalized to the overall intensity of the 7F1 band (magnetic dipole transition Unique features for different crystal structures are indicated with arrows (m monoclinic These lifetimes correspond to 5.1 and 1.6 hydration water entities coordinating to the Cm3+ cation which speaks for an enhanced quenching of the water of hydration in the amorphous solid phase in comparison to Eu3+ Eu3+ in the monoclinic environment appears to reach its maximum for the 32 d sample a slight decrease of the 613 nm peak intensity can be observed while the shoulder at 607 nm increases and the bands in the spectra become broader the emission peak width of the 32 days sample is narrower than the peak width after 117 days aqueous synthesis time which is consistent with the Eu3+ data discussed above and points toward the presence of several Cm3+ environments in these solid phases For a better understanding of the local environment of the trivalent cations in the ZrO2 crystal structure site-selective laser excitation experiments were conducted at 10 K for selected crystalline samples tunable laser excitation is used to selectively probe non-equivalent species in the solid matrix the electrons are directly and selectively promoted from the 7F0 ground state to the emitting 5D0 excited state This technique was performed on the 500-ppm-doped samples after 32 d and 460 d and the 1 mol%-doped samples after 32 d and 399 d aqueous synthesis times laser excitation from the 8S′7/2 ground state to the 6D′7/2 excited state The excited A-state of the curium ion undergoes crystal field splitting giving rise to a maximum of four crystal field states A1−A4 Selective laser excitation to all these crystal field states was performed for samples synthesized for 32 days and 117 days The excitation spectra of the crystalline samples for both Eu concentrations and synthesis times are shown in Fig. 4. Excitation spectra of Eu:ZrO2 with 500 ppm Eu3+ (solid lines and filled symbols) and 1 mol% Eu3+ (dashed lines open symbols) after 32 d (blue) and 460 or 399 d (green) aqueous synthesis times Emission spectra collected at different excitation wavelengths for Eu:ZrO2 samples containing 500 ppm Eu3+ (a one oxygen vacancy is generated in the ZrO2 structure for every two incorporated europium ions to preserve charge neutrality in the crystal structure The presence of these vacancies are likely to decrease the local order and consequently the local symmetry of the solid matrix we assign the Eu3+ environment at 582.1 nm to Eu3+ incorporation in monoclinic ZrO2 with direct coordination to an oxygen vacancy while the species at 582.9 nm is Eu3+ in a pristine m-ZrO2 environment all present Eu3+ species are simultaneously excited with the laser light Radiationless relaxation from a higher-lying excited state to the emitting excited state occurs for example from the cubic/tetragonal phase to the monoclinic phase can occur which is likely the reason for the overrepresentation of the monoclinic environment using this method this could be explained by a lower transition probability for Eu in the cubic/tetragonal structure and a higher probability of the transition for the monoclinic phase The excitation spectra of the Cm:ZrO2 samples for 32 days and 117 days hydrothermal treatment times are shown in Fig. 6. Excitation spectra of the 30-ppm Cm:ZrO2 samples after 32 days (blue) and 117 days (orange) aqueous synthesis times Emission spectra of ZrO2 samples doped with 30 ppm Cm3+ after 32 days (a) and 117 days (b) collected at different excitation wavelengths between 623 and 630 nm (excitation to A2 level) The narrower peak at 649 nm (32 days sample) or 648 nm and 649 nm (117 days sample) are thereby assigned to Cm3+ in a monoclinic ZrO2 structure in accordance with the Eu3+ luminescence data The fact that the peak positions of Cm3+ incorporation in m-ZrO2 are almost identical points toward very similar coordination spheres which in turn is consistent with Cm3+ coordination to seven oxygen anions or six anions and one vacancy This amount is further divided between two Eu3+ environments which differ in their luminescence decay times The presence of a short-lived Eu3+ species a Eu3+ ion partially coordinating to water in the surrounding solution or from Eu3+ coordination to surface-terminated hydroxyl groups at the very superficial sites in the ZrO2 particles The Eu3+ species with a significantly longer luminescence lifetime is indicative of complete isolation of Eu3+ from the surrounding aqueous solution which can be attributed to Eu3+ incorporation into the c + t-ZrO2 bulk material Based on the combined microscopic and spectroscopic results we assign the short-lived Eu3+ species to the visible Eu3+ accumulation at the periphery of the agglomerates Whether the accumulation can be attributed to an overall smaller size of the particles thereby increasing the surface-to-bulk ratio can unfortunately not be deduced from our TEM-based analysis due to the agglomerate formation preventing the unambiguous identification of individual ZrO2 particles Although a definite assignment of the different trivalent environments in the monoclinic ZrO2 structure would require additional studies the formed species were observed to be stable and do not change much during extended periods of aqueous synthesis that the incorporation of trivalent f-elements in the zirconia polymorphs formed after crystallization show a high stability without any signs of dopant segregation from the crystal structure a corrosion product forming on the nuclear fuel rod cladding surface to act as engineered barrier material via structural incorporation of potentially mobilized radionuclides in a DGR Experimental conditions such as elevated temperature and solution chemistry were chosen to mimic conditions that may arise in a generic DGR as a result of radioactive decay and the corrosion of the canister and cementitious backfill and sealing materials Our experiments revealed a successful co-precipitation of Eu3+ as well as Cm3+ with zirconia forming an amorphous hydrous precursor containing multiple incorporation sites of the dopant elements at the initial stage the material underwent crystallization yielding a mixture of mainly the thermodynamically stable monoclinic structure and a smaller fraction of the tetragonal and cubic polymorphs The occurrence of the tetragonal and cubic phases arises from the structural stabilization due to the introduction of oxygen vacancies reducing the coordination number of the Zr lattice as well as the small crystallite size (< 20 nm) The various phases were stable and did not undergo a phase transformation most likely due to agglomeration of crystallites the trivalent dopants could be located in the different crystal structure polymorphs Although the phase distribution showed that most of the zirconia crystallized in the monoclinic phase a preferential incorporation into the tetragonal and cubic structure was observed this preference for the high-temperature polymorphs was not evident Over the entire synthesis duration of up to 460 days the dopant remained structurally incorporated in the crystal structure and did not undergo phase segregation TEM-based analysis revealed a clear accumulation of the dopant at the particle peripheries resulting in an additional dopant environment This environment in characterized by a clearly shorter luminescence lifetime in comparison to incorporated species either as a result of direct Eu3+ coordination to water in the surrounding solution or from Eu3+ coordination to surface-terminated hydroxyl groups at the very surface of the ZrO2 particles the dopant resides in a superficial and bulk environment STEM and luminescence spectroscopy measurements revealed trivalent cations to be structurally embedded into ZrO2 during slightly elevated temperature hydrothermal experiments present as cladding corrosion material of spent fuel rods in a DGR would additionally be suitable to act as engineered barrier material for immobilization of mobilized trivalent cations by structural uptake of these mobilized species Future studies will focus on the role of pH towards the immobilization of trivalent actinides within the different zirconia polymorphs spectroscopic investigations of Eu3+- and Cm3+-doped monoclinic ZrO2 obtained via high-temperature calcination routes are planned to elucidate the origin of multiple dopant environments in the m-ZrO2 crystal structure and the unusually large spectral shifts acquired for the Cm3+-doped material M3+-doped hydrous zirconia samples were prepared by dissolving ZrOCl2·8 H2O (Sigma-Aldrich > 99.99%) in 0.01 M HCl using a 1:2 ratio mass (g)/volume (mL) resulting in a Zr4+ concentration of 1.55 M The trivalent cation was added to the Zr solution from a stock solution of 0.1 M EuCl3·6 H2O in 1 mM HCl or 0.1 mM 248Cm3+ in 0.01 M HClO4 to obtain the desired dopant concentrations of 500 ppm and 30 ppm (Cm) in the hydrous zirconium precursor The concentration of the dopants refers to the number of M3+ per total M3+ + Zr4+ cations in doped ZrO2 assuming quantitative incorporation of the cations from solution into the formed co-precipitate this mixed solution was added dropwise under constant stirring to a 0.5 M NaCl solution in a ratio of approximately 1:20 for Eu3+ doped and 1:28 for Cm3+ doped samples (M3+/M4+ solution: NaCl) The pH was readjusted to its initial value of 12 with 2 M NaOH The suspension was left for 24 h at room temperature before the solid phase was recovered via centrifugation of the suspension for 30 min at 4000 rpm An aliquot of the supernatant was taken for Inductively-Coupled Plasma Mass Spectrometry (ICP-MS for Eu) or Liquid Scintillation Counting (LSC for Cm) analysis to ensure complete uptake of the dopant the dopant concentration in the supernatant was below the detection limit thereby confirming the quantitative uptake of the dopants by the formed solid phase The rest of the liquid phase was discarded and the wet solid was washed twice with MilliQ water (18.2 MOhm) The washing step included addition of 40 mL of MilliQ water into the Greiner tubes and immediate centrifugation of the suspension subsequently discarding the washing solution The dry solid was ground in an agate mortar into a fine powder To probe whether the M3+ dopant was (1) adsorbed onto the Zr-containing precipitate or (2) formed a separate phase such as a hydroxide or hydroxy carbonate rather than a co-precipitate Adsorption of Eu3+ on the amorphous precipitate was investigated at pH 12 non-doped hydrous zirconia was precipitated in the absence of Eu3+ 60 mg of the precipitate were thereafter suspended in 40 mL of 0.5 M NaCl at pH 5 25 µL of a 0.01 M EuCl3 \(\cdot\) 6 H2O stock solution were added The pH 12 was adjusted gradually over the period of two days by manual addition of small aliquots of NaOH under continuous stirring to avoid large pH-fluctuations and to minimize the risk of immediate precipitation of the europium The samples were then equilibrated at room temperature for 24 h the suspension was centrifuged for 30 min and the wet solid was dried at 80 °C for 24 h The pure Eu precipitate was synthesized by dropwise addition of the acidic 0.1 M Eu3+ stock solution to a 0.5 M NaCl solution at pH 12 The suspension was centrifuged for 30 min and afterwards washed twice with MilliQ water The white precipitate was dried at 80 °C for 24 h 120 mg of the doped zirconia powder was submerged in 40 mL 0.5 M NaCl and the pH was adjusted to 12 with 2 M NaOH This resulted in a 1:3 ratio volume (mL)/mass (mg) The suspension was transferred into a 50 mL plastic Greiner tube and stored in an oven at 80 °C for the desired amount of time the sample was taken out of the oven and cooled down to room temperature The sample was then centrifuged for 30 min and washed with 20 mL MilliQ water twice The solid was dried at 80 °C for 24 h and then ground in an agate mortar into a fine powder for further analysis 100 mg of the powder was submerged in 13.3 mL 0.5 M NaCl with pH values of 5 and 12 resulting in a 1:7.7 ratio volume (mL)/mass (mg) The hydrous zirconia sample at pH 5 was solely used for comparison to adsorption investigations to elucidate the role of surface adsorption in the removal of f-elements from solution in the zirconia precipitation step Time-dependent hydrothermal studies were only conducted for the samples prepared at pH 12 the samples underwent the same treatment as the Eu-doped samples All Cm-involving tasks were performed insight a glovebox with negative pressure in N2 atmosphere and carbonate-free solutions To follow the crystallization of the ZrO2 solid phase as a function of the hydrothermal synthesis time and to identify the structural modifications (monoclinic Powder X-ray diffraction (PXRD) analyses were performed on a Rigaku MiniFlex 600 using a Cu Kα X-ray source (40 kV/15 mA operation for X-ray generation) Samples were finely ground in an agate mortar The samples containing inactive Eu3+ were measured on a silicon wafer in the 2θ range between 5° and 90° with a step size of 0.02° 2Θ/min while spinning the Si wafer The radioactive Cm-containing samples were prepared inside a glovebox under N2 atmosphere using an air-tight sample holder consisting of a Kapton-domed silicon wafer The Cm-containing samples were measured in a range between 5° and 60° 2Θ with a step size of 0.02° 2\(\Theta\)/min without spinning to avoid possible contamination of the sample holder The crystallinity was only determined for the inactive samples by the addition of 20 wt% monocrystalline silicon as an internal standard to each sample followed by thorough grinding of the sample mixture into a homogenous fine powder references of the monoclinic (space group:\(P{2}_{1}/c\)) and tetragonal (\(P{4}_{2}/nmc\)) zirconia modification as well as silicon (\(Fd\overline{3}m\)) were used in the PDXL2 software (Rigaku Corporation) and 04-014-8844 (Si) were taken for the refinement The cubic zirconia modification (\(Fm\overline{3}m\)) was not used for the refinement due to the peak width overlapping with the tetragonal modification as we cannot exclude its presence in the synthesized solid phases the quantity of the refined tetragonal phase is referred to as c + t-ZrO2 throughout the text and preferred orientation effects were corrected or accounted for using B-spline and March–Dollase models in the refinement The crystallite size was determined using the Debye–Scherrer Eq. (1): The diffractograms were measured using a Cu X-ray source (\({\lambda }_{C{u}_{\alpha }}=0.154nm\)) \(\Delta \left(2\Theta \right)\) is the full width at half maximum (FWHM) of the diffraction maximum with Θ being the Bragg angle To examine the morphology of the ZrO2 solid phases following aqueous synthesis and the distribution of the dopants within the solid ZrO2 structure high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) imaging combined with spectrum imaging analysis based on energy-dispersive X-ray spectroscopy (EDXS) were performed at an accelerating voltage of 200 kV with a Talos F200X microscope equipped with an X-FEG electron source and a Super-X EDX detector system (FEI) the specimen mounted in a high-visibility low-background holder was placed for 2 s into a Model 1020 Plasma Cleaner (Fischione) to remove possible contaminations The TEM specimens were prepared by creating a very diluted suspension of the sample in MilliQ water and pipetting it onto a carbon-coated TEM grid and letting the water evaporate under ambient atmosphere The Eu3+ and Cm3+ environments in the solid phases were investigated via luminescence spectroscopy Two different spectroscopic approaches were used as explained below All synthesized samples were subjected to luminescence spectroscopic investigations at room temperature using a non-selective excitation wavelength of 394 nm or 396.6 nm capable of exciting all non-equivalent Eu3+ species or Cm3+ species These non-selective luminescence spectroscopic experiments were performed using a pulsed dye-laser (NarrowScan Radiant Dyes) with a 1:1 dye mixture of Exalite 389 and Exalite 398 The Eu3+ luminescence emission spectra were recorded in a range between 575 and 645 nm while a spectral range between 560 and 700 nm was used for Cm3+ The spectra were recorded using the Andor SOLIS software The laser pulse energy was measured to be between 2 and 3 mJ Luminescence emission spectra were detected using an optical multichannel analyzer (Shamrock 303i) with 300 or 600 lines/mm grating and an iCCD camera (iStar Delayed spectra for the identification of the Eu3+ or Cm3+ species with different lifetimes were recorded by delaying the signal detection after the laser pulse up to 15 ms (Eu) or 800 μs (Cm) Luminescence lifetime measurements were performed by collecting multiple spectra and stepwise increasing the time delay of the signal detection and the laser pulse between 20 and 500 µs Based on the results of the non-selective luminescence spectroscopic investigations the chosen samples were subjected to additional spectroscopic experiments with selective tunable laser excitations in a He-cooled cryostat < 10 K (Janis and Sumitomo The samples were placed in a copper sample holder covered by quartz glass a Nd:YAG pump laser (Continuum SureLite II) was coupled to a dye system (NarrowScan Radiant Dyes) containing Rhodamine 6G/Rhodamine B (560–585 nm) An optical multichannel analyzer (Shamrock 303i) with gratings of 150 and 1200 lines/mm and an iCCD camera (iStar The laser energy was measured by the help of an energy meter (Newport 1918-R) which gave the mean energy while collecting one spectrum which was later used for normalizing the resulting excitation spectrum The exact wavelength was measured with a wavelength meter (High Finesse WS-5) All spectra were recorded via the Andor SOLIS software The datasets used and/or analyzed during the current study available from the corresponding authors on reasonable request Zur Abtrennung Langlebiger Radionuklide 152–167 (Radioaktivität und Kernenergie Zirconia-based materials for transmutation of americium and curium: Cubic stabilized zirconia and zirconium oxide pyrochlores Immobilization of radiotoxic elements with Y-stabilized zirconia: The thorium case Quantifying the timing and rate of crustal evolution: Global compilation of radiometrically dated detrital zircon grains Phase equilibria and ordering in the system ZrO2-Y2O3 Beach sand of SE Australia traced by zircon ages through ordovician turbidites and S-type granites of the Lachlan Orogen to Africa/Antarctica: A review Detailed characterization of a PWR fuel rod at high burnup in support of LOCA testing Stabilized zirconia as a structural ceramic: An overview One-step preparation of CaO-doped partially stabilized zirconia from fused zirconia Electrospinning of Y2O3- and MgO-stabilized zirconia nanofibers and characterization of the evolving phase composition and morphology during thermal treatment Effect of Fe2O3 doping on sintering of yttria-stabilized zirconia Chemical synthesis and structural characterization of nanocrystalline powders of pure zirconia and yttria stabilized zirconia (YSZ) Role of a low level of La2O3 dopant on the tetragonal to monoclinic phase transformation of ceria-yttria co-stabilized zirconia phase stability and properties of zirconia polycrystals In Science and Technology of Zirconia V (eds Badwal et al.) 30–48 (Technomic Publishing Company Stability of doped zirconia under extreme conditions: Toward long-term and secure storage of radioactive waste Preparation and properties of black Ti-doped zirconia ceramics The crystallization process of HfO2 and ZrO2 under hydrothermal conditions The occurrence of metastable tetragonal zirconia as a crystallite size effect Mechanisms of room temperature metastable tetragonal phase stabilisation in zirconia Low-temperature hydrothermal synthesis of yttrium-doped zirconia powders Phase development in the metastable solid solutions of ZrO2-YO1.5 system Influence of pH on the hydrothermal crystallization kinetics and crystal structure of ZrO2 Reactive transport modelling of the long-term interactions of corrosion products and compacted bentonite in a HLW repository in granite: Uncertainties and relevance for performance assessment Modelling iron–clay interactions in deep geological disposal conditions Application of cement-based materials as a component of an engineered barrier system at geological disposal facilities for radioactive waste—a review Nuclear waste canister materials: Corrosion behavior and long-term performance in geological repository systems In Geological Repository Systems for Safe Disposal of Spent Nuclear Fuels and Radioactive Waste 2nd edn (eds Apted TRLFS of Eu3+ and Cm3+ doped La2Zr2O7: A comparison of defect fluorite to pyrochlore structures Differences between zirconium hydroxide (Zr(OH)4·nH2O) and hydrous zirconia (ZrO2·nH2O) Influence of the host phase on the vibrational spectra of europium-doped zirconia prepared by hydrothermal processing Monitoring the t → m martensitic phase transformation by photoluminescence emission in Eu3+-doped zirconia powders Understanding the local structure of Eu3+- and Y3+-stabilized zirconia: Insights from luminescence and X-ray absorption spectroscopic investigations Structural and optical properties of europium doped zirconia single crystals fibers grown by laser floating zone Optical properties of Cm(III) in crystals and solutions and their application to Cm(III) speciation A spectroscopic study of trivalent cation (Cm3+ and Eu3+) sorption on monoclinic zirconia (ZrO2) Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides On the relation between lattice parameter and O/M ratio for uranium dioxide-trivalent rare earth oxide solid solution Actinide interaction with Zr-bearing phases: Spectroscopic investigations of An3+ sorption and incorporation reactions with zirconia Stable colloidal suspensions of nanostructured zirconium oxide synthesized by hydrothermal process Hydrothermal crystallization kinetics of m-ZrO2 and t-ZrO2 Solubility of zirconium(IV) hydrous oxides Effect of cation dopant radius on the hydrothermal stability of tetragonal zirconia: Grain boundary segregation and oxygen vacancy annihilation 3Y-TZP ceramics with improved hydrothermal degradation resistance and fracture toughness Stabilization of the tetragonal structure in zirconia microcrystals A stabilization mechanism of zirconia based on oxygen vacancies only Spectroscopy of optical centers of Eu3+ ions in partially stabilized and stabilized zirconium crystals Relationship between local structures and ionic conductivity in ZrO2-Y2O3 studied by site-selective spectroscopy Lanthanide ion probes of structure in biology Laser-induced luminescence decay constants provide a direct measure of the number of metal-coordinated water molecules Determination of the hydration number of Cm(III) in various aqueous solutions Download references Special thanks to Verona Kolpe for creating the graphical abstract the use of the HZDR Ion Beam Center TEM facilities is acknowledged This work was supported by the Department of Energy Office of Nuclear Energy under NEUP Grant DE-NE0009169 and the Bundesministerium für Bildung und Forschung (BMBF) AcE Grant (02NUK060) 03SF0451 in the framework of HEMCP funded the TEM Talos Institute of Ion Beam Physics and Materials Research Department of Materials Science and Engineering Department of Chemical and Biomolecular Engineering Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations Download citation DOI: https://doi.org/10.1038/s41598-023-39143-0 a shareable link is not currently available for this article Sign up for the Nature Briefing newsletter — what matters in science Finland: Finland’s transmission system operator Fingrid will build a new 400 kV and 110 kV transmission line connection over the 69 km from Huittinen to Forssa The new transmission line will enable the growing electricity production surplus on the west coast of Finland to be transmitted to Southern Finland Construction of the transmission line will begin next year and the connection will be completed in 2025 The new 400 kV transmission line connection will increase the electricity transmission capacity from the west coast to Southern Finland and significantly improve energy efficiency reducing the power losses incurred in electricity transmission by 48,000 megawatt-hours per year It will also enable renewable electricity generators to connect to the grid The new transmission line connection will also allow for better maintenance outages and increase the fault tolerance of the grid the new 110 kV Metsämaa substation will be built in Loimaa helping to improve system security in the area Construction of the transmission line will begin in 2023 The investment cost of the project is approximately €60 M New electricity deal and planned gas pipeline aim to ease Syria’s energy crisis with 400 kV line and 6 million m3 of gas daily from Turkey Christian Bruch visits Baghdad to formalise agreement aimed at potentially adding 14 GW to Iraq’s energy capacity through infrastructure upgrades Xcel Energy will build a 280-km transmission line linking clean energy from southwest Minnesota to over 1 million homes across the Upper Midwest © 2013-2025 | All Rights Reserved MERIT MEDIA INT 03-27-2019WORLD CHANGING IDEAS BY Adele Peters “One of the uniquely Finnish experiences which contributes to our well-being is our special relationship with nature, especially our forests,” says Hetta Huittinen, a spokesperson for Business Finland, which launched Rent A Finn a new contest that will bring travelers to Finland this summer for a free trip with a Finnish guide The guide include Hanna–a marketing professional who plans to take visitors to her grandmother’s house by a lake to hike and bake Finnish pastries–and Esko who will host visitors at a summer cottage on the edge of the Arctic Circle (in Rovaniemi which claims to be the hometown of Santa Claus) “Studies have shown that spending time in nature can relieve stress hence the concept of a Finnish ‘happiness guide,’ who can showcase to our visitors how Finns experience nature to relieve stress.”‘ a national park is a short ride away on public transportation “You don’t have to go far from Helsinki to just enjoy silent an entrepreneur who is serving as one of the guides for the program “You just go one bus ride or train ride and you’re in the middle of nowhere.” Juutilainen plans to take visitors to the park a sauna built inside a tent using stones and wood from the seashore Saunas are closely tied to how Finnish people experience nature the public has the right to jokamiehenoikeus it’s legal for anyone to make temporary use of the land “There are no fences at all,” says Juutilainen “You’re allowed to go anywhere and pick berries and mushrooms or whatever you find there or even stay overnight in a tent without asking permission.” Most Finns also spend long stretches of time outside in the summer as they rent or borrow cottages in the countryside; the law requires a minimum of five weeks of annual leave (U.S and it’s not uncommon to take off four weeks in the summer whether someone feels like they have freedom to make life choices and levels of generosity and trust in a society the report doesn’t measure happiness in the moment–Finns rank 41st in terms of everyday emotional state and rise to the top only in the broader sense of whether they are happy with their lives.) Finland is known for its top-ranked public schools, cheap universal daycare, long paid paternity leave, and multiple other programs and policies that improve quality of life. It ranks high on gender equality and low on income inequality. Helsinki has short commutes and is trying to make it easier to live without a car But health and well-being are one part of the overall picture one of the authors of the World Happiness Report Next year’s report will include a chapter that focuses on how the environment around people influences their happiness “People actually are both happier and healthier when they see trees when they’re walking to work,” he says adding that the slow pace of walking and connecting with others also has a benefit “It has implications for how you design cities.” Health and a sense of work-life balance seem to be innate in the culture: When I first tried to contact someone for this article he couldn’t talk because he was headed to the sauna It might be difficult for visitors to glean much wisdom from a two- or three-day trip but Business Finland hopes that the winners chosen to travel will learn something by diving into nature with a Finn “Love of nature and an appreciation for slow living are key contributors to Finnish happiness,” says Huittinen and spend a great deal of time in nature in general.” The final deadline for Fast Company’s Brands That Matter Awards is Friday, May 30, at 11:59 p.m. PT. 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Learn More a global leader in providing high-quality customized pneumatic solutions is proud to celebrate its 50th anniversary this year Pimatic has emerged as a trusted name in the industry and systems for applied pneumatics and low-pressure hydraulics It has been at the forefront of applied pneumatics since its inception and its continued success can be attributed to its dedication to providing innovative solutions for various industries The company was founded by Tapio Heino and Martti Pulli in 1973 and the operations started in February 1974 The initial impetus to establish Pimatic arose not only from the favorable competitive situation but also from Heino's frustration with the long delivery time of parts coming from abroad only a little pneumatic equipment was manufactured in Finland which is why the delivery time of imported parts could stretch to weeks and months Pimatic will celebrate the anniversary all year long The celebrations start with the anniversary gala for employees 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Pimatic is Finland's leading supplier of applied pneumatics and low-pressure hydraulics it is the proven partner in pneumatic solutions for many leading global manufacturers in their industries Pimatic Oy – Pneumatic Opportunity Dacke Industri is a long-term owner that invests in innovative technology companies within selected niches with potential for development We provide expertise and strategic guidance to build sustainable companies over time We follow a decentralized model where our companies have a high degree of autonomy and are run independently.  Our companies have their own products or systems with a strong technical focus The companies use existing platforms for innovation and work towards environmentally sustainable products and production Today Dacke Industri has 22 subsidiaries within 4 divisions Dacke Industri is owned by Nordstjernan since January 2016.  Dacke Industri | With long term ownership in focus Colloids and Surfaces A: Physicochemical and Engineering AspectsCitation Excerpt :In a pH range of 5∼6 DC existed in an electrically neutral state while the dimethylamino groups in DC were positively charged which then enhanced the electrostatic attraction with MACB and MACB/CC and led to higher adsorption performance in this pH range [21] DC appeared in a deprotonated anionic form which established an electrostatic repulsion with the deprotonated functional groups of MACB and MACB-CC thereby leading to decreased adsorption performance [22] The data regarding the equilibrium pH (pHe) of DC adsorption on MACB and MACB-CC shown in Fig 3 suggested that increasing initial pH from 2.0 to 11.0 resulted in a corresponding increase in pHe from 2.4 to 10.1 HELSINKI FINLAND JUser: :_load: Unable to load user with ID: 58 EX-MINISTER Aki Lindén (SDP) informed the Social Democratic Party last November that police have summoned him to an interview in connection with a pre-trial investigation into procurements made by the Hospital District of Helsinki and Uusimaa (HUS), Tytti Tuppurainen, the chairperson of the Social Democratic Parliamentary Group, revealed to STT on Monday Helsinki Police Department on Monday announced it has wrapped up the investigation into the procurements has been submitted to a prosecutor for consideration of charges with three people suspected of violating their official duties over failure to abide by provisions of the public procurement act The procurements were made directly without a competitive tendering process According to Turun Sanomat who served as the chief executive of HUS in 2010–2018 Lindén denied all wrongdoing in an interview with the newspaper underscoring that the investigation does not concern procurements he had made “It’s unfortunate but when you’re in a position of responsibility in a large organisation these kinds of things can happen,” he commented to Turun Sanomat A third party audited the operations of HUS in 2019 concluding that while it is impossible to determine the exact number or value of non-tendered procurements a significant number of contracts had been extended by e-mail without competitive tendering with the value of non-tendered contract extensions in 2016–2019 alone adding up to almost 80 million euros The Market Court issued a penalty payment to the hospital district in 2020 “The police pre-trial investigation examined serious suspected shortcomings in procurements, as well as their planning and monitoring. The shortcomings led to HUS having neither a complete picture of procurements by the joint municipal authority, nor the ability to recognise and organise re-tendering for the procurements,” said Lauri Huittinen the detective chief inspector leading the investigation at Helsinki Police Department Tuppurainen on Monday stated to STT that Lindén informed the party and its national leadership immediately after police had invited him for an interview in November 2022 Also the regional leadership of the party was notified about the development “Police pre-trial investigations are secret until the possible charges are read out some day at a district court,” she reminded declining to reply when asked about the decision not to inform the public about the suspicions before the parliamentary elections STT pointed out in its report that the secrecy of pre-trial investigations applies principally to the content of investigation materials but it does not preclude anyone from disclosing their status as a suspect HUS has declined to both disclose the roles of the suspects and whether any of them continue to work for the district have been suspended from duty because of the suspicions Advertisement inquiries and other after-sales issues: info@helsinkitimes.fi Helsinki Times is the first and only English language newspaper providing news about Finland in English A weekly print edition of Helsinki Times was published from March 2007 up until Feb Helsinki Times is an online-only publication and other groups and individuals interested in Finland from all around the world © Helsinki Times All rights reserved.  Terms of Use | Privacy Policy Open image viewerPolice suspect a woman kidnapping a baby after assaulting its mother in Huittinen. Police later located the woman and baby in Helsinki. Image: Laura Merikalla / YleYle News2.10.2023 13:22Ilta-Sanomat on Monday reportedOpens an external website that a 21-year-old woman from Pori is suspected of a child abduction that occurred in Huittinen on suspicion of aggravated kidnapping and assault the suspect fled with the newborn to Helsinki A few hours later the authorities found the suspect and baby in Helsinki The Southwest Finland Police have described the alleged crime as exceptional and serious and what makes this case even more exceptional is that the victim and perpetrator did not know each other as most kidnappings relate to custody disputes "Child abductions are not common in Finland It's almost impossible to find a similar comparison from the past," Hannu Lauerma Perpetrators generally act spontaneously when it comes to kidnappings involving very young children This could mean the perpetrator grabbing a stroller holding a child when caregivers aren't looking Lauerma said perpetrators are generally delusional or mentally ill there is at least some degree of premeditation and that's why there are hardly any Finnish comparisons," Lauerma explained Would you like a roundup of the week's top stories in your inbox every Thursday? Then sign up to receive our weekly email Metrics details We studied the Cm(III) retention by calcium silicate hydrate (C-S-H) portlandite (Ca(OH)2) and their alteration products calcite and aragonite in high ionic strength carbonate-containing solutions representing specific formation waters we synthesized C-S-H gels with calcium to silicon (C/S) ratios of 1.0 and 2.0 in the absence and presence of Cm(III) resulting in Cm(III)-free and Cm(III) doped C-S-H gel For phase identification purposes we applied X-ray diffraction (XRD) while for the identification of the Cm(III)/C-S-H binding mode we applied site-selective time-resolved laser-induced luminescence spectroscopy (TRLFS) The stability of Cm(III) doped phases under repository-relevant conditions was evaluated by studying the time-dependent release of Cm(III) from the Cm(III) doped C-S-H gel into leaching solutions containing 0.02 M NaHCO3 or 2.5 M NaCl/0.02 M NaHCO3 over 60 d Speciation changes of Cm(III) due to leaching were followed with TRLFS while C-S-H structure alterations and secondary phase formation were monitored with XRD From the results it could be concluded that Cm(III) is not mobilized by aqueous carbonate but either remains incorporated in the C-S-H structure and portlandite or becomes partially re-immobilized into secondary CaCO3 phases The presence of NaCl led to an accelerated conversion of metastable secondary CaCO3 phases into calcite Concrete will be used as part of the multi-barrier system in a deep geological nuclear waste repository to ensure mechanical stability and sealing of disposal tunnels against formation water Whether such mobilization will occur also for actinides in other oxidation states should to allow predictions of the long-term safety of nuclear waste repositories and gamma radiation over a long time period makes their retention by barriers of a deep geological repository mandatory Pu and the aforementioned MAs can exist as trivalent cations in repository environments the present study focuses on understanding the interaction of trivalent actinides with C-S-H phases in saline solutions As representative for the trivalent actinides we have chosen the luminescent cation Cm(III) which enables laser-induced luminescence spectroscopic investigations of the actinide retention mode in the studied systems The authors observed the formation of aqueous Cm(III) carbonate complexes at pH values ≤ 10 the objective of the present work was to study the stability of Cm(III) doped C-S-H gel in solutions containing 0.02 M NaHCO3 or 2.5 M NaCl/0.02 M NaHCO3 representative for formation water present in some claystone deposits to evaluate the retention capability of a HCP barrier towards Cm(III) under repository-relevant conditions C-S-H gel samples with two C/S ratios 2.0 and 1.0 representing a portlandite saturated C-S-H system as well as chemically degraded cement paste site-selective TRLFS was applied for Cm(III) doped C-S-H gel and complimented by XRD investigations before and after leaching experiments to study potential alterations of the C-S-H structure the formation of secondary phases as well as potential changes of the Cm(III) binding mode The exposure of CaO and fumed silica to the alkaline Cm(III) solution led to a Cm(III) uptake of 98.5 and 97.1% into the solid C-S-H phases having C/S ratios of 1.0 and 2.0. This corresponds to retardation coefficients (Rd) of 2.7 × 103 and 1.2 × 103 L/kg (Table 1) ascribed the high uncertainty in the Rd values to an extremely strong sorption of Eu(III) on the C-S-H phase and a possible incomplete phase separation during centrifugation leading to the presence of colloids in the supernatant Since in the present study a centrifuge with only 3,059 × g could be used for Cm(III) samples it is possible that the observed low Rd values are also caused by an incomplete phase separation which is often applied as a non-radioactive analog for trivalent actinides Eu(III) doped C-S-H phases with C/S ratios of 1.0 and 2.0 were synthesized under conditions identical to our Cm(III) doped C-S-H phases These samples were centrifuged at 40,000 × g for 1 h the supernatants were analyzed for Eu(III) resulting in Rd values of 1.6 × 106 L/kg for both C/S ratios This shows that the low Rd values for Cm(III) in the present study were indeed caused by an incomplete phase separation Since the Cm(III) speciation on solid C-S-H particles present in the supernatant should be identical to that on the solid it is expected that the incomplete phase separation has no influence on recorded XRD patterns or TRLFS spectra XRD patterns of Cm(III)-free C-S-H samples with C/S ratios of 1.0 and 2.0 in comparison to C-S-H and portlandite references top black lines) of sample 1 (left) and sample 2 (right) and recorded emission spectra (a-k gray lines) after excitation at different wavelengths: (a) (604.1 nm) pointing towards the presence of more than one species After selectively exciting around 620 nm, multiple narrow emission spectra with two visible shoulders at slightly longer wavelengths (red-shifted) become visible (Fig. 2 The magnitude of the red-shift of these two shoulders is 0.5 nm and 1.2 nm from the main peak independent of the excitation wavelength used these shoulders can be ascribed to a partially resolved splitting of the 8S7/2 ground state Assumed positions of Cm(III) in the crystal structure of calcium silicate hydrate (calcium (green) corresponding to Cm(III) species with 2 and 0 water molecules in the first coordination sphere of the actinide cation The exposure of sample 1 (C/S 1.0) to solutions that contain either 0.02 M NaHCO3 or 2.5 M NaCl/0.02 M NaHCO3 over a time period of 14, 30 or 60 d led to a negligible Cm(III) mobilization between 0.01 and 0.5% of the previously incorporated Cm(III) (Table 2) comparable NaHCO3 concentrations should lead to a stronger complexation of U(VI) by carbonate compared to Cm(III) differences in the S/L ratio and a higher pH after leaching contribute to the lower Cm(III) release compared to U(VI) XRD patterns of the Cm(III)-free C-S-H gel with a C/S ratio of 1.0 before and after leaching in 0.02 M NaHCO3 (left) and 2.5 M NaCl/0.02 M NaHCO3 (right) depending on leaching time: (a) (before leaching) (f) (difference between measured and calculated spectra after 30 d) No clear trend in terms of CaCO3 phase conversion was found over 1 month probably caused by the combination of two effects aragonite should be converted constantly into calcite due to its metastable nature the rotation of the samples during leaching grinds the samples creating new C-S-H surfaces that are exposed to the carbonate solution which promotes the formation of metastable aragonite halite reflections were detected originating from drying the leached C-S-H gel which leads to a crystallization of NaCl residues in the samples Despite the clear transformation of a part of the C-S-H structure into secondary phases the very low Cm(III) release from C-S-H gel points towards either incongruent leaching of the sample where Cm(III) remains in the C-S-H structure or a Cm(III)-re-immobilization into the formed secondary CaCO3 phases To trace the association of Cm(III) in the solid mixtures site-selective TRLFS analyses of the solids after leaching were performed TRLFS spectra of sample 1 (C/S 1.0) after leaching in 0.02 M NaHCO3 (left) for 14 d and in 2.5 M NaCl/0.02 M NaHCO3 (right) for 14 d (gray lines) and 60 d (blue lines) (A–C) Excitation spectra after 14 d (black lines) (D–F) Excitation spectra after 60 d (blue lines) (A,D) Integrated over the complete emission spectrum (B,E) Integrated over the C-S-H main band (~615–625 nm) (C,F) Integrated between the C-S-H hot and main band (~605–615 nm) Recorded emission spectra after excitation at different wavelengths: a (605.2 nm) blue lines) at 608.0 and 612.8 nm indicates that these emission lines are caused by Cm(III) incorporation into aragonite that is probably present in amounts below the XRD detection limit The aragonite phase is converted into calcite over time due to its metastable nature causing the decrease of the Cm(III)/aragonite emission lines due to the overlap of the signals of Cm(III) incorporated in calcite with those of Cm(III)/C-S-H gel we cannot detect this species in the current system To investigate the influence of the portlandite phase on the stability of the Cm(III)/C-S-H system, sample 2 (C/S 2.0) was leached in either 0.02 M NaHCO3 or 2.5 M NaCl/0.02 M NaHCO3. Comparable to sample 1, the leaching of sample 2 leads only to a very low Cm(III) release between 0.05 and 0.7% of the previously incorporated Cm(III) (Table 4) To get a deeper understanding of the phase conversion of portlandite and C-S-H in these leaching solutions, XRD patterns of a Cm(III)-free C-S-H gel with a C/S ratio of 2.0 leached in 0.02 M NaHCO3 and 2.5 M NaCl/0.02 M NaHCO3 were recorded (Fig. 6). XRD patterns of the Cm(III)-free C-S-H gel with a C/S ratio of 2.0 before and after leaching in 0.02 M NaHCO3 (left) and 2.5 M NaCl/0.02 M NaHCO3 (right) depending on leaching time: (a) (before leaching) TRLFS spectra of sample 2 (C/S 2.0) after leaching in 0.02 M NaHCO3 (left) for 14 d and in 2.5 M NaCl/0.02 M NaHCO3 (right) for 14 d (gray lines) and 60 d (blue lines) Recorded emission spectra after excitation at different wavelengths: a (605.4 nm) c) is caused by Cm(III) remaining in portlandite Combined TRLFS and XRD results suggest that the majority of Cm(III) remains in the C-S-H and portlandite phases after leaching in saline carbonate-containing solutions A minor incorporation or sorption of Cm(III) in calcite cannot be excluded due to the main band overlap of the Cm(III)/calcite and Cm(III)/C-S-H system site-selective TRLFS investigations (at about 10 K) on Cm(III)-containing C-S-H gel were successfully applied The additional combination with batch leaching experiments and XRD studies resulted in important information about the Cm(III)/C-S-H binding mode and Cm(III) retention by cementitious materials in complex high ionic strength pore waters a luminescence line-narrowing effect was detected during the site-selective TRLFS measurements of the present study which indicates variations of the local Cm(III) coordination environment in C-S-H gel chemically similar binding sites for Cm(III) which can be attributed to the amorphous to semi-crystalline structure of the C-S-H gel C-S-H gel with a C/S ratio of 2.0 showed a co-incorporation of Cm(III) into portlandite The Cm(III) mobilization from Cm(III) doped C-S-H gel in the leaching solutions 0.02 M NaHCO3 or 2.5 M NaCl/0.02 M NaHCO3 was very low (0.1 to 0.7% after 60 d) regardless of C/S ratio XRD investigations of the C-S-H samples leached in 0.02 M NaHCO3 revealed that C-S-H gel and portlandite are partly converted into secondary CaCO3 phases such as calcite and aragonite (C/S 1.0) or calcite and vaterite (C/S 2.0) After leaching in 2.5 M NaCl/0.02 M NaHCO3 exclusively calcite was detected as secondary phase Site-selective TRLFS investigations after leaching showed that Cm(III) was still incorporated in C-S-H gel and in addition either partially incorporated into the secondary phase aragonite (C/S 1.0) or still incorporated by portlandite (C/S 2.0) which was clearly identified in the leached C-S-H gel by XRD is expected but could not be verified by TRLFS due to the overlap of the luminescence signals of Cm(III) incorporated in calcite with those of Cm(III) incorporated in C-S-H gel An incorporation of Cm(III) into calcite is also expected after the conversion of the metastable CaCO3 phases aragonite and vaterite into the stable phase calcite For the conditions applied in the present study (S/L ratio of 10 g/L also for conditions foreseen for nuclear waste repositories containing protective barriers of concrete (very high S/L ratios) the results of leaching experiments and site-selective TRLFS showed that an almost complete retention of Cm(III) by cementitious materials and their alteration phases can be expected even in the presence of carbonate-containing solutions with increased ionic strengths C-S-H gel syntheses and leaching experiments were performed in an inert gas glove box (N2 atmosphere CO2 < 3.8 ppb) at 25 °C using degassed deionized water (18 MΩ cm; mod A 4 × 10−6 M 248Cm stock solution in 0.1 M HClO4 was used for the synthesis of Cm doped C-S-H gel 248Cm is a radionuclide with a half-life of 3.48 × 105 years decaying through α-emission (92%) and spontaneous fission (8%) The use of 248Cm requires the appropriate infrastructure and personnel trained in the handling of alpha-emitting isotopes Germany) and carbonate-free CaO (anhydrous surface carbonate was removed by washing the NaOH pellets several times with degassed deionized water in a Büchner funnel under inert gas atmosphere The total inorganic carbonate concentration of the prepared NaOH solution determined with a multi-N/C 2100 S (Analytik Jena where c0 and ceq [mol/L] are the initial and equilibrium Cm(III) concentration V [L] represents the solution volume and m [kg] the C-S-H mass The synthesized Cm(III) doped C-S-H gel samples were stored as wet pastes Cm(III)-free C-S-H gel samples used in the XRD investigations were synthesized accordingly but 3.6 mL deionized water were added instead of the Cm(III) stock solution Leached C-S-H gel samples were stored as wet pastes for further characterization All leaching experiments were performed as duplicates For the evaluation of the Cm(III) binding mode on C-S-H and formed secondary phases The method allows for selective excitation of non-equivalent Cm(III) species in the investigated system by tuning the excitation wavelength (λex) to match the transition energy between the 8S7/2 ground state and the 6D7/2 emitting state of the individual species The excited 6D7/2 state of the curium ion undergoes crystal field splitting of about 300–600 cm−1 due to ligand interactions giving rise to a maximum of four crystal field states (hot bands) This crystal field splitting is rather small resulting in thermally populated crystal field states at ambient temperatures In systems with multiple non-equivalent curium species some overlap of hot band transitions of energetically lower-lying species with the main transition of higher-lying species In systems that possess a semi-crystalline character such as the C-S-H structure investigated in the present study the environment of an incorporated luminescent species is rather ill-defined resulting in a multitude of chemically similar but not identical Cm(III) environments in the amorphous bulk These non-equivalent Cm(III) species will have slightly different energy states resulting in a multitude of overlapping emission lines and further in so called luminescence line-broadening of the collected excitation spectra where kobs is the decay rate (reciprocal lifetime) [ms−1] of the excited state and n(H2O/OH−) represents the number of coordinated water molecules or hydroxyl ions for TRLFS measurements the dried solid samples were transferred into an Al sample holder and covered with a quartz plate (Qiopitq The site-selective TRLFS measurements were performed with a pulsed Nd:YAG (Continuum Surelite II USA) pumped dye laser set-up (Radiant Dyes Narrow Scan K) A combination of laser dyes such as sulforhodamine B and rhodamine 101 were used to enable tuning of the excitation wavelength between 600 and 630 nm the samples were cooled with a helium-refrigerated cryostat below a temperature of 12 K The emission signal was collected by a fiber coupled optical multi-channel system consisting of a polychromator with 600 and 1200 lines/mm gratings and an intensified CCD camera model iStar (Andor Emission measurements were accumulated over 5,000 spectra while excitation and time-resolved measurements were accumulated over 100 spectra Luminescence lifetimes were monitored as a function of delay time between 10 and 1,570 µs in 40 µs steps The excitation spectra were energy corrected for each wavelength using the average energy collected with an optical power meter (Newport 1918-R) XRD analyses of Cm(III)-free C-S-H gel samples before and after leaching were performed to characterize the solid phases including secondary phases formed due to leaching The diffractograms were collected with a MiniFlex 600 diffractometer (Rigaku Japan) equipped with a Cu Kα X-ray source (40 keV/15 mA operation for X-ray generation) and the D/teX Ultra 1D silicon strip detector in the Bragg-Brentano θ-2θ geometry at a scanning speed of 0.6° per min The samples were mounted as wet pastes on a zero-background Si sample holder and stored for several minutes in an inert gas atmosphere to remove excess water from the samples and thus to minimize carbonation of the samples during measurements The subsequent Rietveld analysis of diffractograms was done with the program PDXL 2 (Rigaku) and the ICDD PDF-4+ 2016 database (C-S-H phase (database card number 00-033-0306) portlandite (database card number 01-083-4600) calcite (database card number 01-083-4601) aragonite (database card number 01-075-9985) vaterite (database card number 04-017-8634) and halite (database card number 00-005-0628)) The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request In A Practical Guide to Microstructural Analysis of Cementitious Materials Uptake of trivalent actinides (curium(III)) by hardened cement paste: a time-resolved laser fluorescence spectroscopy study Diffusion of radionuclides in concrete and concrete-bentonite systems Reproducibility of the uptake of U(VI) onto degraded cement pastes and calcium silicate hydrate phases Uptake of Np(IV) by C-S-H Phases and Cement Paste: An EXAFS Study Uptake of actinides by calcium silicate hydrate (C-S-H) phases Structure of calcium silicate hydrate (C-S-H): Near- Thermodynamic Modeling of Cement Degradation - Impact of Redox Conditions on Radionuclide Release U(VI) sorption on Ca-bentonite at (hyper)alkaline conditions - Spectroscopic investigations of retention mechanisms In Petroleum Geological Atlas of the Southern Permian Basin Area Herkunft und Genese geothermaler Tiefengrundwässer im Norddeutschen Becken (NDB) und deren Relevanz für die geothermische Nutzung The hydrogeochemistry of argillaceous rock formations at the Horonobe URL site Long-term Used Nuclear Fuel Waste Management ‒ Geoscientific Review of the Sedimentary Sequence in Southern Ontario Stability of U(VI) doped calcium silicate hydrate gel in repository-relevant brines studied by leaching experiments and spectroscopy Hydration and carbonation of monoclinic C2S and C3S studied by Raman spectroscopy Structural features of C-S-H(I) and its carbonation in air - A Raman spectroscopic study SCALE 5.1 Predictions of PWR Spent Nuclear Fuel Isotopic Compositions Np and Pu in spent nuclear fuel in an oxidizing environment Uptake of Cm(III) and Eu(III) by calcium silicate hydrates: A solution chemistry and time-resolved laser fluorescence spectroscopy study Thermodynamics of Cm(III) in concentrated salt solutions: Carbonate complexation in NaCl solution at 25 degrees C Sorption mechanisms of Eu3+ on CSH phases of hydrated cements Hydrophobic Properties of Calcium-Silicate Hydrates Doped with Rare-Earth Elements A New Incorporation Mechanism for Trivalent Actinides into Bioapatite: A TRLFS and EXAFS Study A spectroscopic and computational study of Cm3+ incorporation in lanthanide phosphate rhabdophane (LnPO4 × 0.67H2O) and monazite (LnPO4) Complexation Behavior of Humic Substances Towards Actinides and Lanthanides Studied by Time-Resolved Laser-Induced Spectrofluorometry Thermodynamics of Radioactive Trace-Elements in Concentrated Electrolyte-Solutions - Hydrolysis of Cm3+ in NaCl-Solutions Uranyl(VI) carbonate complex formation: Validation of the Ca2UO2(CO3)(3)(aq.) species Quantitative analysis of accelerated carbonation products of the synthetic calcium silicate hydrate(C-S-H) by QXRD and TG/MS Promotion mechanism of co-existing NaCl in the synthesis of CaCO3 Incorporation of trivalent actinides into calcite: A time resolved laser fluorescence spectroscopy (TRLFS) study Incorporation versus adsorption: substitution of Ca2+ by Eu3+ and Cm3+ in aragonite and gypsum Phase transformation in CaCO3 polymorphs: A spectroscopic Th(IV) and Pu(IV) hydrous oxides in CaCl2 solutions and the formation of ternary Ca-M(IV)-OH complexes Lanthanide Ion Probes of Structure in Biology - Laser-Induced Luminescence Decay Constants Provide a Direct Measure of the Number of Metal-Coordinated Water-Molecules Luminescence Study on Determination of the Hydration Number of Cm(III) Download references The German Federal Ministry for Economic Affairs and Energy (BMWi) is thanked for financial support (No Atsushi Ikeda-Ohno (HZDR) is thanked for helpful discussions and advice with regard to XRD measurements conducted the site-selective TRLFS measurements sample preparation and batch leaching experiments helped with the set-up refinement and data interpretation of the site-selective TRLFS measurements conceived the experiments and contributed to discussion and interpretation of results All authors contributed to and reviewed the manuscript Download citation DOI: https://doi.org/10.1038/s41598-019-50402-x Metrics details Cr-doped UO2 is a leading accident tolerant nuclear fuel where the complexity of Cr chemical states in the bulk material has prevented acquisition of an unequivocal understanding of the redox chemistry and mechanism for incorporation of Cr in the UO2 matrix we have used electron paramagnetic resonance high energy resolution fluorescence detection X-ray absorption near energy structure and extended X-ray absorption fine structure spectroscopic measurements to examine Cr-doped UO2 single crystal grains and bulk material Ambient condition measurements of the single crystal grains which have been mechanically extracted from bulk material indicated Cr is incorporated substitutionally for U+4 in the fluorite lattice as Cr+3 with formation of additional oxygen vacancies Bulk material measurements reveal the complexity of Cr states where metallic Cr (Cr0) and oxide related Cr+2 and Cr+32O3 were identified and attributed to grain boundary species and precipitates with concurrent (Cr+3xU+41-x)O2-0.5x lattice matrix incorporation The deconvolution of chemical states via crystal vs powder measurements enables the understanding of discrepancies in literature whilst providing valuable direction for safe continued use of Cr-doped UO2 fuels for nuclear energy generation bulk Cr-doped UO2 can be considered a complex system with respect to the variable chemical states Cr can simultaneously adopt This creates a considerable experimental challenges in redox state determination in both fresh and irradiated Cr-doped UO2 nuclear fuel using bulk material measurements which most previous investigations have used as it becomes difficult to reliably deconvolute specific Cr chemical states and environments from others within bulk UO2 Although similar results were found between fresh and irradiated Cr-doped UO2 they identified significant parasitic interfering signals from Cr precipitates and grain boundary phases acting along the nanometre scale This prevented the accurate and precisely resolved measurement of the Cr chemical state within the fuel matrix Their work emphasised the complexity of Cr chemical states within Cr-doped UO2 and particularly the challenge of deconvoluting them via bulk measurements We demonstrate that by extracting representative single crystal grains from the bulk material O-K and Cr-K edge images of Cr-doped UO2 pellet (top) with 3500 ppm addition as Cr2O3 shown comparatively with a single crystal grain (bottom) extracted from the same material The grain boundary map of the BSE Cr-doped UO2 pellet has been superimposed on the Cr-K edge EDS map to highlight the distribution of Cr–O phases Note the lack of impurity grains and Cr additions on the surface of the single crystal grain compared to the pellet where considerable Cr oxide and metallic are present in grain boundary regions and as precipitates The dark spots in the single crystal grain BSE are due to voids and note the shadow effect from EDS present in the U-L a Measured and modelled EPR spectra of Cr-doped UO2 single crystal grains at room temperature b Normalised Cr K-edge HERFD-XANES spectra in the range 5980–6050 eV for Cr-doped UO2 as powder and single crystal grain c Normalised Cr K-edge HERFD-XANES spectra in the range 5980–6030 eV for Cr-doped UO2 bulk powder with calculated complementary iterative transformation factor analysis (ITFA) components for Cr0 (metallic) Cr+2Cl2 and Cr+3Cl3·6H2O and d Normalised Cr K-edge HERFD-XANES spectra in the range 5980–6030 eV for Cr-doped UO2 single crystal grain with calculated complementary ITFA components for Cr0 (metallic) We observed the strongest peak at 5989 eV whereas the second strongest is found at 5987 eV for CrCl2 The Cr2O3 spectrum shows two pre-edge peaks at ~5990.5 and ~5987.5 eV The small energy difference recorded at the pre-edge between the two references in +2 and +3 oxidation states indicates that pre-edge region potentially contains fingerprint information on the oxidation state changes of complex Cr systems other factors like the presence of various ligands and metal spin state will contribute to the changes of the pre-edge features and must be examined and considered in depth before the generalised measure of oxidation state is applied to the pre-edge Inspecting Fig. 2b it can be observed that there is a clear shift of the main edge transitions between metallic Cr (Cr0) The first metallic transition appears at 5991 eV while the CrCl2 spectrum shows two main peaks at 5993 eV and 5997 eV The main edge excitations shift further to the highest incident energy for the Cr+3 compounds Cr K-edge main peak of CrCl3 is at 6006 eV while the K-edge spectrum recorded on Cr2O3 shows a splitting of the main edge features to transitions at ~6004.5 and ~6008.5 eV These two transitions reflect the crystal field splitting of the 4p states in Cr2O3 local coordination the position of the main edge transitions appears at the same energy range for Cr+3Cl3·6H2O and Cr2O3 indicating that Cr K-edge HERFD-XANES can be used as a fingerprint for the oxidation state determination of complex Cr-containing systems is attributed to metallic and oxide precipitates and grain boundary phases The spectrum recorded on the Cr-doped UO2 single crystal grain exhibits a prominent peak at ~5991 eV that is also present in the metallic Cr the peaks at the 5993 and 5997 eV that belong to CrCl2 are absent in the Cr-doped UO2 single crystals spectrum This indicates and further supports the premise that Cr in the bulk powder differs considerably compared to the single crystal grain in terms of the variety of Cr oxidation and chemical states present That the main edge peak of the Cr-doped UO2 single crystal grain matches that of Cr+3Cl3·6H2O indicates the local environment and oxidation state of the Cr cation in the UO2 lattice matrix and CrCl3·6H2O are near identical The Cr+3 cation in CrCl3·6H2O (space group R\(\bar{3}\)c) has a distorted octahedral environment with a coordination number (CN) of six to the O ligands in the hydrate The results of the Cr K-edge HERFD-XANES measurement of the Cr-doped UO2 single crystals are consistent with the previous EPR analysis namely that Cr+3 cation resides in a substitutional position in a distorted octahedral environment to oxygen in the UO2 lattice with a neighbouring oxygen vacancy defect for charge compensation with the formula (Cr+3xU+41−x)O2−0.5x the HERFD-XANES measurements provide no evidence for Cr+2 in the lattice matrix and preclude its occurrence and further reinforces the overall mechanism of incorporation via (Cr+3xU+41−x)O2−0.5x for Cr lattice incorporation following oxygen vacancy defect formation and not U+5 formation The k3 weighted EXAFS data show small differences between the Cr-doped powder sample and the single crystal grain These differences are likely to arise from the compositional differences such as the clear presence of Cr+2 centres in the polycrystalline sample in contrast to the single crystal grains are dominated by structurally incorporated Cr+3 in a CrCl3·6H2O-like distorted octahedral environment which is also evident from the EXAFS data when comparing the polycrystalline Cr-doped UO2 and single crystal samples with the chromium standards Fitted k3-weighted Cr K-edge EXAFS spectra (left) and corresponding Fourier transforms (FT) in the spectral range from 2.0 to 8.8 Å−1 (right) of the Cr-doped single crystal grain (top) and powder sample (bottom) Phase shifts (Δ) are not corrected in the FTs The single crystal specimen was measured using HERFD mode on the X-ray emission spectrometer while powder samples were collected in fluorescence mode using an 18-element Ge-detector This reduction in metal-to-oxygen bond distance would also induce local distortion which is consistent with the previous EPR analysis a very similar difference of 0.47 Å between the obtained Cr–U bond length and the crystallographic U–U distance can be derived implying that the considerable distortions to the crystal lattice upon the incorporation of the small trivalent chromium cation are not dampened for the second coordination shell With these rather large differences between the local environments of the dopant and the host cations it is clear that the theoretical calculations using UO2 as input structure did not yield a satisfactory description of the measured EXAFS data both UO3 and CrUO4 have Cr/U–O distances like those we obtained for our single crystal grain Structural representation of the box-shell incorporation model of the incorporation of Cr into the UO2 lattice matrix forming (Cr+3xU+41−x)O2−0.5x as derived from the EPR HERFD-XANES and EXAFS analysis of this investigation The 1st box-shell (purple) highlights the Cr+3 cation incorporation which involves the formation of an oxygen vacancy defect The 2nd box-shell (cyan) indicates the locally distorted U lattice region derived from EXAFS analysis which showed shorter Cr–U distances resembling an environment closer to UO3 or CrUO4 than that of U–U in pristine UO2 The 3rd box-shell (dark blue) which resembles closely that of the U+4O2 lattice far enough away from the Cr+3 cation to not receive significant lattice distortions the uranium cationic lattice stays consistently as U+4 this experimental investigation has incontrovertibly established the mechanism of lattice incorporation for Cr and its associated secondary chemical states that occur in Cr-doped UO2 nuclear fuels and subsequently enable optimum measurement signal resolution considering the small size of single crystal grains The ADU mixtures were firstly calcined under air to oxide form using a box furnace at 800 oC for 5 h prior to reduction to UO2 at 600 °C under 4% H2–96% Ar atmosphere for an additional 5 h the pre-treated powders were compacted into pellets and heated to 1700 oC using a tube furnace for 10 h with a µO2 of −420 kJ/mol that was monitored and produced via a 4% H2–96% Ar with 1% H2–99% Ar gas mixture The furnace was cooled to room temperature using a ramp rate of 6 oC/min whilst the gas mixture was maintained samples were carefully mechanically divided for specific measurement analysis a semi-automatic segmentation of grain boundaries and the determination of grain sizes EDS spot analyses as well as EDS elemental mappings to determine the spatial distribution of Cr were carried out at 20 kV and a working distance of 10 mm Single crystal grains were measured neat pre-EPR HERFD-XAS and EXAFS measurements to check crystal purity and particularly the absence of surface and subsurface Cr oxide impurities and contaminants and Cr-coated Zircaloy ATF concepts(Idaho National Laboratory (INL) Advanced doped UO2 pellets in LWR applications On the solubility of chromium sesquioxide in uranium dioxide fuel Fission gas release and swelling in UO2 doped with Cr2O3 AREVA NP new UO2 fuel development and qualification for LWRs applications In Top fuel 2006 International Meeting on LWR Fuel Performance "Nuclear Fuel: Addressing the future" Chromium doped UO2-based ceramics: synthesis and characterization of model materials for modern nuclear fuels Hot Isostatic Pressing (HIP): a novel method to prepare Cr-doped UO2 nuclear fuel The +2 oxidation state of Cr incorporated into the crystal lattice of UO2 Al) UO4 from doped UO2 and its influence on partition of soluble fission products Factors governing microstructure development of Cr2O3-doped UO2 during sintering Irradiation effects and micro-structural changes in large grain uranium dioxide fuel investigated by micro-beam X-ray diffraction Aqueous leaching of Cr2O3-doped UO2 spent nuclear fuel under oxidizing conditions Evolution of the uranium concentration in dissolution experiments with Cr–(Pu) doped UO2 in reducing conditions at SCK CEN Role of electronic effects on the incorporation of Cr at a Σ5 grain boundary in UO2 Thermodynamics of chromium in UO2 fuel: a solubility model Microbeam X-ray absorption spectroscopy study of chromium in large-grain uranium dioxide fuel Raman spectroscopy coupled to principal component analysis for studying UO2 nuclear fuels with different grain sizes due to the chromia addition Solution of trivalent cations into uranium dioxide The role of dopant charge state on defect chemistry and grain growth of doped UO2 Chromia doped UO2 fuel: investigation of the lattice parameter Local atomic structure of chromium bearing precipitates in chromia doped uranium dioxide investigated by combined micro-beam X-ray diffraction and absorption spectroscopy Equilibrium phase relations and thermodynamics of the Cr–O system in the temperature range of 1500 °C to 1825 °C High-energy resolution X-ray spectroscopy at actinide M4,5 and ligand K edges: what we know High temperature chromium volatilization from Cr2O3 powder and Cr2O3-doped UO2 pellets in reducing atmospheres Electron Paramagnetic Resonance in Compounds of Transition Elements (John Wiley & Sons Surface chemistry and spectroscopy of chromium in inorganic oxides Charge compensation mechanisms in Nd-doped UO2 samples for stoichiometric and hypo-stoichiometric conditions: lack of miscibility gap Paramagnetic defects in polycrystalline zirconia: an EPR and DFT study Measurement and interpretation of the thermo-physical properties of UO2 at high temperatures: the viral effect of oxygen defects Charge distribution near bulk oxygen vacancies in cerium oxides HERFD-XAS and valence-to-core-XES: new tools to push the limits in research with hard X-rays Complexation of uranium (VI) with protocatechuic acid—application of iterative transformation factor analysis to EXAFS spectroscopy Sensitivity to actinide doping of uranium compounds by resonant inelastic X-ray scattering at uranium L3 edge Role of resonant inelastic X-ray scattering in high-resolution core-level spectroscopy of actinide materials Chemical thermodynamic representation of UO2±x High energy resolution X-ray absorption spectroscopy of environmentally relevant lead(II) compounds Standard X-Ray Diffraction Powder Patterns (US Department of Commerce Solid-state properties and colloidal stability of thorium(IV)–silica nanoparticles X-ray photoelectron spectroscopy studies of chromium compounds X-ray photoelectron spectroscopy studies of reactions on chromium metal and chromium oxide surfaces Enrichment of chromium at grain boundaries in chromia doped UO2 Characterisation of 3000 ppm Cr2O3 doped UO2 and its precipitates Cr2+ Solid solution in UO2 evidenced by advanced spectroscopy Evaluation and application of a new scintillator-based heat-resistant back-scattered electron detector during heat treatment in the scanning electron microscope New tools for calibrating diffraction setups GSAS-II: The genesis of a modern open-source all purpose crystallography software package Single-crystal structure validation with the program PLATON a comprehensive software package for spectral simulation and analysis in EPR A Johann-type X-ray emission spectrometer at the Rossendorf beamline HEPHAESTUS: data analysis for X-ray absorption spectroscopy using IFEFFIT EXAFSPAK: a suite of computer programs for analysis of X-ray absorption spectra (Stanford Synchrotron Radiation Laboratory Winxas: a program for X-ray absorption spectroscopy data analysis under Ms-windows Real-space multiple-scattering calculation and interpretation of X-ray-absorption near-edge structure Download references are grateful to funding and support from the German Federal Ministry of Education and Research (BMBF) Juliane März is kindly acknowledged for her help collecting single crystal grains for the EPR measurements The ESRF Chemistry Laboratory personnel Harald Muller and Léa Bourcet are acknowledged for their help with the glove-box facility Andrey Bukaemskiy is kindly acknowledged for assistance in pellet pressing and polishing Gregory Leinders is kindly thanked for fruitful discussions on the thermodynamics of UO2 Institute of Energy and Climate Research (IEK-6) The project was conceived and developed by G.L.M and formal analysis was jointly conducted by G.L.M Single crystal grains were extracted and characterised with single crystal X-ray diffraction by G.L.M Synchrotron powder diffraction measurements and analysis were performed by G.L.M. Electron paramagnetic measurements and analysis were performed by R.G. SEM measurements and analysis were made by R.T X-ray absorption spectroscopy measurements were performed by G.L.M. Nature Communications thanks Chantal Riglet-Martial, Jacques Lechelle and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Peer reviewer reports are available Download citation DOI: https://doi.org/10.1038/s41467-023-38109-0 soaking some buildings in Huittinen and Pori Open image viewerHeavy slush on the River Kokemäki in Pori's Kivini district Image: Katja Halinen / YleWif Stenger20.1.2018 14:48•Updated 20.1.2018 14:50Officials say that heavy slush on the Kokemäki River has caused the worst winter flooding in south-western Finland in over a decade On Saturday the situation had improved in town of Huittinen The level of the Kokemäki River there had declined by about half a metre from that of the past few days The improvement came after military engineers exploded dams of tightly-packed slush and ice on the river and slowed its flow Slush flooding occurs when ice crystals become tightly packed into dams of slush water levels remained at Friday's flood level flood waters threatened homes in Pori's Kivini district Water has entered some structures in Huittinen and Pori However no damage is reported to residential buildings The situation is the worst since at least 2005 senior water resource expert at the Southwest Finland Centre for Economic Development Transport and the Environment (ELY Centre) "Historically the worst slush flooding situations have been around this point of the winter in 1974-75 and in 2004-05," he told the Finnish News Agency STT on Friday Triipponen says the situation is now at least as bad as that in the winter of 2004-05 Colder weather is expected to improve the situation by forming a solid ice cover on the river Readings of around -10 degrees Celsius are forecast for the rest of the weekend and early next week Defence Forces called in to help flood-proof Turku motorwayPublished 20172017More water damage detected at new housing blocks in HelsinkiPublished 20172017Sources: Yle, STT but the 17-year-old llama escaped her duties and is now being pursued instead Open image viewerNemorosa is a fairly large white llama Image: Anu KoivistoYle News2.7.2021 15:40•Updated 3.7.2021 11:03A 17-year-old llama named Nemorosa escaped from the western Finland town of Punkalaidun on Wednesday night but Nemorosa was still on the lam on Friday roaming somewhere along the border of the Pirkanmaa and Satakunta regions in the town of Huittinen The last sighting of Nemorosa was made on Wednesday evening in a forest area in Huittinen Llama farmer Anu Koivisto said it is unlikely that Nemorosa was still in the forest "The woods are a scary place for a llama She is wearing a harness but will probably be scared if someone attempts to grab it the easiest way to catch a llama is to approach it calmly with a piece of dry bread or oats she will quickly turn into a humble walking companion," said Koivisto "Nemorosa can spit if she feels cornered but it is not dangerous," said Koivisto The transfer of Nemorosa and her llama buddy was related to a WWF project testing out llamas as guardians against wolves llamas are used in various parts of the world as herd protectors against predators like wolves as llamas do not instinctively flee from predators "We were to test out llamas as guardians against predators in Finland," said Koivisto it will likely escape again," said Koivisto From the weird to the wonderful: Nine free things to do in Finland this summerPublished 20212021Conditional SentenceSuspended sentence for hybrid wolf breederPublished 20212021Sources: Yle cut off roads in western FinlandSpring rains arriving in western Finland Thursday have pushed up water levels in the Lapväärtinjoki 30 centimetres Local officials say homes in Huittinen are already under water and roads are impassable in some areas Open image viewerKauhajoella tulvavesi nousi pelloille ja katkoi teitä 18 Image: Yle19.4.2013 8:13•Updated 19.4.2013 12:52Rising water levels in the Lapväärti River in Kristiinankaupunki western Finland are threatening to inundate homes in the area The Finnish Environmental Administration confirmed that surface waters in the river rose 30 centimetres as a result of rain Thursday The spring melt has also caused overflows in the Kyrönjoki with embankments in the Kyrönjoki under even more water than during floods last October On Thursday evening the flood waters cut off Highway 3 which was being used to re-route some local traffic Meanwhile scores of homes in Huittinen were in danger of flooding or had already been overtaken by the rising waters of the Loimijoki which had swept through the city centre overnight Head of the local water resource management unit Juha-Pekka Triipponen said that mopping up operations had already been initiated at the river near the downtown area “The discharges are much more powerful than back in 1984 about 270 cubic metres per second,” he added Chief hydrologist Bertil Vehvilainen of the Environmental Administration said that in Oulunkylä the Vantaa River was just 40 centimetres from breaching its banks the river had already overflowed its banks  Vehvilainen speculated that the impact of recent rains on rising water levels should ease Friday afternoon at the latest “Although we see the impact of the rain rather quickly Open image viewerImage: Yle UutisgrafiikkaRoads cut off in some areasThis year’s spring floods have disrupted road networks in many areas One major artery was affected in Hollola in the Päijät-Häme region in southern Finland while in Ostrobothnia some roads have been completely cut off and closed to traffic in Pudasjärvi Residents of Jalasjärvi will also find that Ahon siltatie is impassable due to flooding Locals in western and parts of southern Finland should check their local authorities for detailed information about which areas have been worst affected Waters hit flood levels in western areasPublished 20132013Spring floods threaten western FinlandPublished 20132013Sources: Yle