Heavy rain and the overflowing Acre River flooded wide areas of the city of Rio Branco
the capital of the state of Acre in Brazil
The city recorded 124.4 mm of rain in 24 hours to 23 March 2023
according to figures from Brazil’s Instituto Nacional de Meteorologia (INMET)
The Acre River at Rio Branco jumped from around 8 metres to 15.80 metres in 24 hours
Streets and homes were damaged across 10 neighbourhoods including Placas
Authorities helped to evacuate some residents who took refuge in school buildings in the Conquista neighbourhood
Flooding has continued in the city since then
with the Acre River rising to 16.96 metres
As many as 2,213 people have evacuated their homes
The river has also flooded areas in the municipalities of Assis Brasil
In Xapuri levels of the Acre River stood at 15.16 metres (flood level is 15 metres) and in Brasileia the river reached 13.62 metres (flood level is 11.40 metres)
flooding from the Acre River has affected almost 15,000 people
local authorities reported 433 displaced in Assis Brasil; 8,886 displaced in Brasileia; and 316 displaced in Xapuri
Flooding along the Acre river is also affecting areas of the Pando Department in Bolivia
which sits on the banks of the Acre opposite the city of Brasileia
Bolivia’s Ministry of Health reported at least 300 families have been affected or evacuated
Five shelters have been opened to accommodate those displaced
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A photonic connection between turbulence and spin glasses has been recently established both theoretically and experimentally using a random fiber laser as a photonic platform
it links the works of two 2021 Nobel laureates in Physics
two of the most elusive physical phenomena that lie at the very heart of the seminal works by Hasselmann and Parisi
resulting in an open disordered complex system with suitable gain and scattering to provide the optical feedback for RL action
The Nobel Committee for Physics. The Nobel Prize in physics 2021: scientific background. 28 Mar 2022. https://www.nobelprize.org/prizes/physics/2021/advanced-information/ (2022)
Glassy behavior in a one-dimensional continuous-wave erbium-doped random fiber laser
Turbulence hierarchy in a random fibre laser
Coexistence of turbulence-like and glassy behaviours in a photonic system
Recent advances and applications of random lasers and random fiber lasers
Toward a mean field theory for spin glasses
Infinite number of order parameters for spin-glasses
Experimental evidence of replica symmetry breaking in random lasers
The laminar-turbulent transition in a fibre laser
Dynamical Systems Approach to Turbulence 215 (Cambridge University Press
Feynman diagrams and interaction rules of wave-wave scattering processes
Nonlinear interactions treated by the methods of theoretical physics (with application to the generation of waves by wind)
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DOI: https://doi.org/10.1038/s41377-022-00793-w
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By: Marcos Araújo Mortoni Silva and Rafael Encinas
the Brazilian Court of Audit (TCU) and the Comptroller General of the Union audited the Automotive Regional Development Policies (PADR) of the Brazilian government
granted tax credits to automobile manufacturers that established factories in less developed regions of Brazil.
The PADR costs R$5 billion per year in tax benefits and currently benefits four companies
which have factories located in the cities of Goiana and Belo Jardim
The audit was structured to allow for a comprehensive opinion on the current situation of the PADR regarding its maturity as public policies and their results
Figure 1 presents the analytical framework and audit questions that were developed for the work
Figure 1 – Analytical framework of the PADR Audit
The RCPP presents an analytical rationale structured in control blocks (Figure 2)
designed in line with the phases of the policy cycle
providing a conceptual basis and a toolkit for guiding public policy analyses (Figure 3)
Figure 2 – Analytical structure of the RCPP and policy cycle
Figure 3 – RCPP – toolkit for public policy analysis
The RCPP served as an integrating reference for relevant analytical and methodological perspectives in public policies in the audit of the PADR
facilitating dialogue between the team and the internal supervisors and decision-makers of the TCU on common ground
since incentives and constraints influence agents in their decisions
the audit was innovative and also considered this context in the analysis of the PADR.
consolidated perspectives from the literature
such as public choice theory and agency theory
were adopted for the formulation of questions
and justification of the characterization of the causes and effects of the audit findings
This analytical framework was highly useful in demonstrating the material relevance of accountability for the effectiveness of governments in public policies
the method was developed to estimate the effects of aggregate interventions
interventions that are implemented at an aggregate level
affecting a small number of large units (such as cities
it is “arguably the most important innovation in the policy evaluation literature in the last 15 years.”
The method is primarily used in comparative case studies
comparing the evolution of the outcome variable in the unit that received the government intervention with a set of untreated units that
form the counterfactual of the treatment unit.
Although the PADR currently benefits four automotive factories
the impact assessment was only possible for a factory inaugurated in 2015 due to data availability
as the national indicator databases did not have information prior to the inauguration of the other factories.
municipalities are grouped into two levels of regions (IBGE
Immediate regions are characterized by integration into the urban network
based on nearby urban centers that satisfy the immediate needs of the populations
Intermediate regions correspond to an intermediate scale between the federal unit and the immediate region
delimited by the inclusion of metropolises
or representative urban centers for a set of immediate regions (IBGE
Both types of regions were defined as the territory for impact assessment.
Figure 4 shows the map of the state of Pernambuco with the division of its immediate and intermediate regions
The immediate region where the evaluated factory was installed is the region shaded in dark green
composed of eleven municipalities and a population of approximately 350,000 inhabitants
The light green-shaded region is the intermediate region
which encompasses the immediate region of the factory
with the immediate and intermediate regions where the factory was installed
The synthetic control evaluation indicated a significant impact on per capita GDP
and total remuneration in the immediate region that benefited from the PADR
Figure 5: Results of the synthetic control analysis for per capita GDP
the proportion to the population in the treated immediate region reached 14.64% in 2019
The difference of 3.24% over the population of the region corresponds to 11,258 jobs generated.
the factory received R$4.6 billion (USD 1.1 billion) through tax incentives
which corresponds to R$388 million (USD 92.4 million) per month
resulting in a monthly cost of the policy per job created of R$34,000 (USD 8,100)
a high cost considering the national minimum wage of R$998 (USD 238) or the amounts transferred by other social programs
The results of the impact assessment were supported by employment generation data from national records
which indicated low job creation in other sectors of the economy
with a migration of jobs to the automotive sector
information on the factory’s input purchases showed that only 6% of suppliers were from the target regions of the policy
while 94% were acquired from companies in more developed regions.
The conclusions are aligned with studies from multilateral organizations such as the OECD (2015) and the World Bank (Kronfol & Steenbergen
which state that tax incentives alone do not have the ability to attract investments
as other factors are equally or more important in the decision-making process of private agents
The maturity analysis of public policies adopted in the audit of the PADR can be replicated by Supreme Audit Institutions (SAIs)
with contextualizations as necessary.
The applicability of the content of the RCPP needs to be verified on a case-by-case basis
as its criteria are largely based on Brazilian legal frameworks
as well as the competencies and jurisprudence of the TCU
the analytical framework of the RCPP and its toolkits
developed based on the phases of the policy cycle
being useful for the assembly of audits aimed at a comprehensive analysis of public policies.
The adoption of theoretical perspectives that consider the behavior of agents can also be replicated for the maturity analysis of policies
but as a scientific basis to guide investigative perspectives and explain the causes of findings in audits of public policies.
The impact assessment conducted in the audit of the PADR can also be used in audits that evaluate public policies in various sectors
The synthetic control method allows for the construction of a counterfactual in case studies
and other policies on large aggregates such as municipalities
a large professional exhibition area was designed to give Congress participants the opportunity to share knowledge and experiences through networking
regional organizations and other affiliated groups were represented at booth spaces throughout the week-long event…
193 nations of the United Nations General Assembly put pen to paper and agreed to sign on to implement 17 Sustainable Development Goals (SDGs)
How can citizens be sure a nation’s government follows through on these commitments…
Kuwait’s State Audit Bureau welcomes a new President and continues its international training
including contributions to the Young EUROSAI (YES) Conference held in London last November…
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Random lasers (RLs) are remarkable experimental platforms to advance the understanding of complex systems phenomena
such as the replica-symmetry-breaking (RSB) spin glass phase
Here we study these three phenomena jointly in a Nd:YAG based RL synthesized for the first time using a spray pyrolysis method
We propose a couple of modified Pearson correlation coefficients that are simultaneously sensitive to the emergence and fading out of photonic intermittency turbulent-like effects
Our results show how intertwined these phenomena are in RLs
and suggest that they might share some common underlying mechanisms
possibly approached in future theoretical models under a unified treatment
RLs differ from regular lasers in the optical feedback mechanism
Whereas in regular lasers the feedback is provided by a static cavity generally formed by two mirrors
in RLs the optical feedback comes from the stimulated photons in the gain medium that are randomly scattered in a disordered material
including optical and electrical pumping associated with gain media
or active materials as semiconductors and rare-earth doped ions
a photonic glassy phase with RSB was predicted in the RL regime above threshold
in which the modes cannot oscillate in a synchronous way
presenting nontrivial correlations captured by the Parisi overlap parameter
we demonstrate that the joint analysis of the modes dynamics correlations
and intermittency turbulent-like effects can be performed from a couple of modified Pearson coefficients
our experimental study system is a Nd-based RL consisting of Nd3+ ions in YAG micron crystal powder (Nd:YAG)
synthesized for the first time using a spray pyrolysis method
which enabled us to control the composition of particles and crystalline phase
That fast methodology produces particles in a few minutes
without coalescence and might allow also to produce these materials on a large scale
Our results reveal the concurrent onset of enhanced mode correlations
photonic RSB and turbulence behavior in the Nd:YAG RL
We argue that these complex photonic phenomena result from a unique combination of key ingredients
a suitable disorder strength of gain and scattering elements
all of them unveiled in this work from a single set of measurements of intensity fluctuations
We employed a spray pyrolysis method to synthesize the particles of Nd:YAG (4.0% mol/mol to Y3+), with average diameter of 0.6 μm, see “Methods” section for details
Characterization of the emitted intensity and FWHM of the Nd:YAG RL
(a) RL spectral evolution from an excitation pulse energy below the threshold (0.3 mJ) to well above threshold (1.3 mJ)
(b) Emitted intensity (left y-axis) and FWHM (right y-axis) versus excitation energy
The energy threshold 0.62 mJ is inferred from (b)
we use Greek letters to represent the spectrum labels and small Latin letters to indicate the wavelength labels
\(I_{\gamma i}\) as the intensity emitted by the Nd:YAG RL at the wavelength \(\lambda_{i}\) in the spectrum \(\gamma\)
\(I_{i}\) is the intensity at the wavelength \(\lambda_{i}\) averaged over the spectra
We also define \(\overline{{\Delta_{\gamma i} }}\) as the relative difference (fluctuation) with respect to this average
\(\overline{{\Delta_{\gamma i} }} = \Delta_{\gamma i} /\sqrt {\sum\nolimits_{K} {\left( {\Delta_{\gamma i} } \right)^{2} } }\)
where \(\Delta_{\gamma i} = I_{\gamma i} - I_{i}\) and capital Latin letters represent either the spectra (e.g.
We then propose a modified Pearson correlation coefficient as follows
where above we use the Einstein summation convention over repeated indexes
that \(\lambda_{i}\) and \(\lambda_{j}\) represent the wavelengths of two modes of the laser system
Then a null value of \(C_{ij}\) implies that these modes behave statistically in an uncorrelated way over the time interval of the spectra series
a positive (negative) \(C_{ij}\) signals that the statistical fluctuations in the intensity of one mode are positively (negatively) correlated to those in the other mode
so that the spatially overlapped coupled modes share (compete for) gain along the measurement
Each horizontal line corresponds to an excitation power
from below threshold (two upper lines: \(P/P_{th} = 0.18\) and \(P/P_{th} = 0.56\))
to around (central line: \(P/P_{th} = 1.32\))
and well above threshold (two lower lines: \(P/P_{th} = 2.07\) and \(P/P_{th} = 2.45\))
a replica-symmetric paramagnetic-like phase identified by a unimodal central peaked \(P\left( q \right) \) coincides with weakly fluctuating spectra and uncorrelated intensity fluctuations with mostly blue heatmaps of the Pearson coefficient
the RSB glassy behavior sets in with two side peaks in \(P\left( q \right)\) along with stronger intensity fluctuations and increasingly correlated modes (orange and red regions in the heatmaps)
Each horizontal line in Fig. 2 corresponds to a value of the excitation power
from the prelasing regime well below threshold
with \(P/P_{th} = 0.18\) and \(P/P_{th} = 0.56\) (two upper lines)
to the RL phase around the threshold with \(P/P_{th} = 1.32\) (center line)
\(P/P_{th} = 2.07\) and \(P/P_{th} = 2.45\) (two lower lines)
indicate the presence of a photonic replica-symmetric paramagnetic-like regime
Since modes overlap spatially and stochastically compete for gain, we note in Fig. 2i,l,o that this competition can favor some subsets of modes
displaying stronger Pearson cross-correlation values
while undermining others with lower correlation (less intense heatmap regions)
We now turn to the joint analysis of intermittency effects along with modes correlations and RSB in the Nd:YAG RL system
Here we also demonstrate this phenomenon in a RL
and further analyze the onset and fading out of intermittency effects with respect to the emergence and persistency of modes correlations and RSB behavior
In fluid turbulence51
the relevant statistical quantities are the velocity increments between two points in the fluid
\(\delta I_{\tau ,\gamma i} = I_{\gamma + \tau ,i} - I_{\gamma i}\)
between spectra \(\gamma\) and \(\gamma + \tau\) separated in time by \({\Delta }t = \tau t_{0} ,\) with integers \(\gamma\) and \(\tau ,\) and \(t_{0} =\) 100 ms as the time interval between two consecutive spectra emitted by the Nd:YAG RL
For a proper statistical analysis including long separation times \(\tau \gg 1\)
we had to take into account a 5 × larger number of spectra (5000)
we conveniently define a variable with null average and unit variance
\(x_{\tau ,\gamma i} = \delta I_{\tau ,\gamma i} /{\text{var}} \left\{ {\delta I_{\tau ,\gamma i} } \right\}\)
where \({\text{var}}\left\{ {\delta I_{\tau ,\gamma i} } \right\}\) is the variance of the long time series of intensity increments
We also choose in our analysis the wavelength \(\lambda_{i}\) of maximum intensity (once \(\lambda_{i}\) is set
we drop the wavelength index \(i\) hereafter)
in which a heavy-tailed PDF of velocity increments sets in between nearby points
but a Gaussian PDF always arises when uncorrelated distant points are considered
The intermittency of the stochastic flux of energy between the relevant time scales is a key ingredient to set the statistical properties of \(P\left( {x_{\tau } } \right)\)
when the intermittent behavior is mitigated
by decreasing the input excitation power and optical nonlinearity degree
the heavy tail of \(P\left( {x_{\tau } } \right)\) fades away and a Gaussian PDF with a single scale variance emerges for any \(\tau\) in the non-turbulent regime below threshold
Intermittency effects and RSB behavior in the Nd:YAG RL. Distributions \(P\left( {Q_{\tau } } \right)\) and \(P\left( {x_{\tau } } \right)\) of the modified Pearson correlation coefficient, Eq. (4)
\(x_{\tau ,\gamma i} = \delta I_{\tau ,\gamma i} /{\text{var}}\left\{ {\delta I_{\tau ,\gamma i} } \right\}\)
of spectra separated in time by \(\tau t_{0} ,\) with \(t_{0} = 100\) ms
The upper (lower) horizontal line corresponds to the excitation power \(P/P_{th} = 0.56\) (\(P/P_{th} = 1.50\)) below (above) threshold
For \(\tau = 0\) the PDF \(P\left( {Q_{\tau } } \right)\) is equivalent to the Parisi overlap distribution \(P\left( q \right)\)
with (a) a single central peak in the replica-symmetric regime below threshold [also seen in (b)] and (e) double side peaks with RSB above threshold
in the latter (former) a Lévy (Gaussian) \(P\left( {x_{\tau } } \right)\) indicates in (h)
(d) the coexistence with a photonic turbulent-like (non-turbulent) regime above (below) threshold
For \(\tau \gg 1\) only Gaussians are found [insets of (c) and (g)]
As the intermittency effects fade away in the crossover from the \(\tau = 1 \) to \(\tau \gg 1\) time scales
a quite distinct statistical behavior of \(P(Q_{\tau } )\) emerges
with the most likely values of \(Q_{\tau }\) in (f) becoming the least probable ones in (g)
for \(\tau > 0\) \(d_{\tau ,\gamma i}\) is equivalent to the intensity increments \(\delta I_{\tau ,\gamma i}\) in the analysis of photonic turbulence
we thus expect that the statistical weight of the replica overlaps with \(\tau \gg 1\) dominates over the long time series of spectra
\(P(Q_{\tau } )\) should actually appear qualitatively similar to the bimodal PDF \(P\left( q \right)\) when the turbulence-like intermittency effects are suppressed for large separation time scales \(\tau \gg 1\)
no critical exponents associated with the glassy transition in these systems have been calculated so far and an ideal photonic glassy system for this purpose should be one in which the number of modes could be experimentally controlled
Our joint analysis of these complex photonic phenomena through a couple of modified Pearson correlation coefficients in the Nd:YAG RL showed how intertwined these behaviors are in a RL system
and indicate that they might share common physical underlying mechanisms
Although it is out of the scope of the present work to propose a theorical model to account for such phenomena
we suggest that a unique combination of key ingredients is subjacent to the mechanisms responsible for such behaviors
as the structural disorder in the distribution of gain and scattering elements
and suitable degree of optical nonlinearity
all of them present in the Nd:YAG RL analyzed here from a single set of measurements of intensity fluctuations
We hope our findings can stimulate the quest for the joint understanding of these complex behaviors under a unified theoretical approach
which can benefit from tools and concepts employed in the separate treatment of such challenging phenomena
12 ml of aqueous yttrium nitrate solution (0.5 M) and 4 ml of neodymium nitrate solution (0.1 M) were added to 20 ml of ultrapure water previously heated to 83 °C
2.43 g (0.01 mol) of the aluminum tri-sec-butoxide was added and hydrolyzed for 1 h under stirring
and 0.5 ml of nitric acid was added as a peptizing agent
The final volume was adjusted to 50 mL with ultrapure water after cooling the suspension
This 0.2 M sol was spray pyrolyzed into the SP system
the aerosol was generated at an ultrasound chamber
where a 2.4 MHz frequency piezoelectric pellet was employed
the aerosol was transported by a gas flow (0.1 m3/h atmospheric air) through two heat treatment zones: the drying zone (150 °C) and the pyrolysis one (700 °C)
In the first the solvent was evaporated and the initial solid particles were attained; and in the second the final material was obtained by a fast heat treatment
the powder was collected in an electrostatic filter (150 °C) operating at 11 kV
the collected powder was further heated at 1100 °C for 12 h
Figure 4 shows the typical morphology and particles size distribution of the powder sample used in this work. The sizes of the spherical particles ranged from 0.1 μm to 2.0 μm, with average diameter of 0.6 μm.
Diameter distribution of micron size Nd:YAG (4.0%) particles synthesized by spray pyrolysis
(Inset) Scanning electron microscopy image of the sample
(a) Excitation spectrum (emission band monitored at 1064 nm) and (b) emission spectrum (under excitation at 808 nm) of the Nd:YAG (4.0%) powder
The most important emission 1064 nm corresponds to the Nd3+ transition 4F3/2 → 4I11/2
The experimental setup shown in Fig. 6 is typically used for powder-based RL studies. The pump source was an optical parametric oscillator (OPO, Opotek) pumped by the second harmonic of a Q-switched Nd:YAG laser and tuned to the 810 nm emission wavelength. A repetition rate of 10 Hz was employed and the source pulse duration was 5 ns.
Experimental setup for measurements in the Nd:YAG RL
M1 and M2 are 100% reflecting mirrors @800 nm
and PBS is a broadband polarizer beam splitter
and the data is acquired by a high-resolution spectrometer with CCD (see text for equipment details)
We used a high-resolution spectrometer (SpectraPro 500
Acton Research Corporation) coupled with a charge-coupled device (CCD)
In the discretization of the spectra the bin width was 0.032 nm
a value that corresponds to the resolution of the acquisition system
To study the RSB behavior and modes correlations
we acquired a series of 1000 spectra for each input excitation energy
and for intermittency effects 5000 spectra were obtained in the regimes below
All relevant data are available from the authors
Generation of light by a scattering medium with negative resonance absorption
Generation of spatially incoherent short pulses in laser-pumped neodymium stoichiometric crystals and powders
Nanocomposite-based random lasers: a review on basics and applications
In Nanocomposites for Photonic and Electronic Applications (eds Kassab
The physics and applications of random lasers
Review on latest developments in random lasers with coherent feedback
Nonlinear effects and photonic phase-transitions in Nd3+ doped nanocrystals based random lasers
Random laser properties of Nd3+ crystal powders
Random lasing in Nd3+ doped potassium gadolinium tungstate crystal powder
Short-pulsed stimulated emission in the powders of NdAl3(BO3)4
Optimal performance of NdAl3(BO3)4 nanocrystals random lasers
Random laser in Nd:YBO3 nanocrystalline powders presenting luminescence concentration quenching
Tunable ultraviolet and blue light generation from Nd:YAB random laser bolstered by second-order nonlinear processes
Polydispersed powders (Nd3+:YVO4) for ultra efficient random lasers
Random laser emission from neodymium doped zinc tellurite glass-powder presenting luminescence concentration quenching
Speckle-free near-infrared imaging using a Nd3+ random laser
Two-color random laser based on a Nd3+ doped crystalline powder
Observation of Lévy distribution and replica symmetry breaking in random lasers from a single set of measurements
Lévy statistics of emission from a novel random amplifying medium: An optical realization of the Arrhenius cascade
Intrinsic intensity fluctuations in random lasers
Statistical regimes of random laser fluctuations
Lévy exponents as universal identifiers of threshold and criticality in random lasers
Analytical solution for the Lévy-like steady-state distribution of intensities in random lasers
Extreme-value statistics of intensities in a CW-pumped random fiber laser
Lévy spectral intensity statistics in a Raman random fiber laser
Lévy statistics and glassy behavior of light in random fiber lasers
Robustness of replica symmetry breaking phenomenology in random laser
Replica symmetry breaking in FRET-assisted random laser based on electrospun polymer fiber
Spin Glass Theory and Beyond (World Scientific
Statistical mechanics models for multimode lasers and random lasers
Strong interactions in multimode random lasers
Toward single-mode random lasing within a submicrometre-sized spherical ZnO particle film
Diverse regimes of mode intensity correlation in nanofiber random lasers through nanoparticle doping
The mode-locking transition of random lasers
Random laser in dye-doped electrospun nanofibers: Study of laser mode dynamics via temporal mapping of emission spectra using Pearson’s correlation
Replica symmetry breaking in a weakly scattering optofluidic random laser
Evaluation of Pearson correlation coefficient and Parisi parameter of replica symmetry breaking in a hybrid electronic addressable random fiber laser
Coexistence of turbulence-like and glassy behavior in a photonic system
Evidence of Anderson localization effects in random Raman lasing
Large fluctuations at the lasing threshold of solid-and liquid-state dye lasers
Elaboration of boehmite nano-powders by spray-pyrolysis
Tuned structure of europium-doped Al2O3-ytrium luminescent composites and their spectroscopic behavior
Random laser action in Nd:YAG crystal powder
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We thank the Brazilian funding agencies Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) (Proc
Fundação de Amparo a Ciência e Tecnologia do Estado de Pernambuco (FACEPE) (APQ-0504-1.05/14
and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) – Finance Code 001
Work performed in the framework of the National Institute of Photonics (INCT de Fotônica-IFO) Project
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) is also acknowledged for the grants received by J.M.A.C
Laboratório de Física Teórica e Computacional
prepared and performed the morphological characterization
developed the theoretical study and statistical analysis of the experimental data
The manuscript was written with the contributions of all authors
The authors declare no competing interests
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations
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DOI: https://doi.org/10.1038/s41598-022-05090-5
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New initiatives set to propel Brazil into the growing market for automotive energy storage systems
Oxis Energy Oxis Energy’s laboratory in England
where its lithium-sulfur battery technology was developedOxis Energy
A vehicle battery is an assembly of smaller batteries
that are integrated into a package and managed by a Battery Management System (BMS)
Application-specific packages are designed by connecting cells in series and parallel
says the new plant will produce cells but not batteries proper—this final stage will be handled by companies dedicated to cell integration with Battery Management Systems (BMS)
“We are currently in the process of selecting integration partners
We hope to attract several to Brazil,” he says
Battery integrators need to be acceptable to and selected by future buyers
Among the OEMS that have expressed interest in sourcing batteries from the new plant are Brazilian aircraft manufacturer Embraer
The joint venture’s lithium-sulfur battery technology has been developed by its UK partner
last year invested R$18.6 million in a 12% stake in Oxis Energy and intends for the production facility in Brazil to provide downstream integration for its lithium supply chain in Minas Gerais
has the potential to become a globally leading producer of the mineral
Oxis Brasil will be the world’s first plant to produce lithium-sulfur batteries at commercial scale
Several other research centers around the world are now also vested in the new technology
Sony is looking to harness lithium-sulfur chemistry in the production of smart phone batteries
while US-based Sion Power Corporation is developing batteries with the technology for automotive applications
is developing new materials and insight into the electrochemical chemistry involved in lithium-sulfur technology
Brazil produced only 600 metric tons (mt) of lithium in 2018
accounting for about 0.7% of the global market
The country’s entire output of the mineral was mined by Companhia Brasileira de Lítio (CBL)
The Geological Survey of Brazil has estimated reserves in Vale do Jequitinhonha to represent 8% of global reserves
Australia and Chile are currently the world’s leading producers
at respectively 51,000 mt and 16,000 mt per year
explains that because of the substances involved and the production process
this combination of materials can create a fire and explosion hazard when exposed to stressors such as warming above 45 ºC
or punctures—as might occur in a vehicle collision
Oxis Energy’s battery solution uses anodes made of lithium metal in replacement of graphite carbon
and cathodes made of a combination of sulfur and carbon
The company has developed its own proprietary technology for both the cathode and the electrolyte solution
These new batteries have been shown by testing to be safe at temperatures ranging from minus 60 ºC to 80 ºC
and will not explode when punctured or shorted
lithium-sulfur batteries also have an edge in energy density
While lithium-ion batteries concentrate a maximum of 240 watt-hours per kilogram (Wh/kg)
lithium-sulfur batteries can store 450 Wh/kg
This allows batteries to be made smaller and lighter
is that lithium-ion batteries are already approaching their theoretical efficiency limit
whereas lithium-sulfur batteries still have potential to evolve further in terms of energy density
“Oxis expects to achieve 550 Wh/kg by early 2020,” she says
CBMM, based in Araxá, southeastern Brazil, is the world’s largest producer of niobium
In 2018 it partnered with Toshiba Corporation to develop new lithium battery technology
Toshiba’s R&D department plans to replace the carbon anode with a titanium-niobium composite oxide (NTO) while maintaining a traditional cathode made of lithium alloy and metal
says that NTO will not react to lithium and generate structural stress
such as a 13% increase in volume when charging
“This allows for more power and faster charging times,” he says
In a comparison of two batteries with the same charge
the lithium-ion version takes four hours to charge
while its NTO counterpart needs just 10 minutes for a full recharge
NTO batteries also have a lifespan of over 15 years in automotive applications
while the best-performing lithium-ion batteries last around 10 years
Another advantage is that NTO anodes are safer when exposed to heat or perforation stress
This year’s Nobel Prize in Chemistry has been awarded to three scientists for research related to lithium batteries
Under the partnership agreement between CBMM and Toshiba
each side will invest US$7.2 million in a pilot plant being built in Yokohama
where the first units are expected to be produced for testing within two years
“We hope to secure OEM approval of the technology in 2021
which will give us the green light for construction of an industrial-scale production line,” says Ribas
Another project exploring applications for niobium in batteries is being developed at Wildcat Discovery Technologies in San Diego
which will employ niobium in making cathodes
The project is still at an early stage of development
According to a report by the International Energy Agency (IEA) titled Global EV Outlook 2019, the most significant recent developments in the industry involve changes in battery chemistry, such as cathodes made of lithium metal oxides with a metal ratio of 80% nickel, 10% manganese, and 10% cobalt, compared with a current ratio with an equal portion of each metal.
Cathodes made of lithium-nickel-cobalt-aluminum oxides, used for smaller-sized batteries, are another research front. For anode applications, silicon-graphite composites have attracted the greatest research interest. The automotive industry expects to see significant progress in improving energy density and reducing costs by 2025.
Moura Group A Moura-owned lead-acid battery facility
now retrofitted to produce lithium-ion rechargeable batteriesMoura Group
says the company will adapt Xalt’s battery technology for the severe operating conditions in Brazil
The batteries will be produced at a new manufacturing facility opened in 2018
Lithium-ion batteries require special safety measures to ensure they are properly sealed and protected from contact with water
They also need cooling systems so they are kept within a safe temperature range
“Vehicles in Brazil are exposed to different weather conditions than vehicles operating in the northern hemisphere,” says the executive
a company housed at the Center for Innovation
and Technology (CIETEC) at the University of São Paulo (USP)
has been developing lithium-ion automotive battery technology since 2007 as a spinoff from a fuel-cell project supported by FAPESP’s PIPE program
The company has established a partnership with Brasil VE Superleves
a manufacturer of super-compact battery electric vehicles hosted at the Anhanguera Business Park in Cajamar
which is due to start production in December
The facility will produce between 40 and 200 units per month
including 2- and 4-seater passenger vehicles
a chemical engineer specializing in the manufacture of lithium batteries in Germany
says the company will initially import battery cells and integrate them into lithium batteries in Brazil
The first shipment of battery cells will come from Germany
but the company also has prospective suppliers in China
“We ultimately plan to produce battery cells locally
We already have the necessary expertise and knowledge of the manufacturing process
We just need to build enough scale to start production,” says Ett
who is also a professor at the FEI University Center in São Bernardo do Campo (SP)
Mechanical engineer Paulo Henrique de Mello Sant’Ana
and Applied Social Sciences at the Federal University of ABC (CECS-UFABC)
says that battery production capabilities will be strategic in a future of electric mobility
It is crucial that Brazil engage in early development of battery technology rather than only buying finished products
“While it’s still too early to say whether initiatives such as the CBMM-Toshiba or CODEMGE-Oxis joint ventures will be economically viable and successful at improving lithium battery performance
it is certainly good news that Brazilian players are now involved in the development process,” he says
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