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1.
Gels ; 10(9)2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39330189

RESUMO

Zn-air batteries (ZABs) are a promising technology; however, their commercialization is limited by challenges, including those occurring in the electrolyte, and thus, gel polymer electrolytes (GPEs) and hydrogels have emerged as substitutes for traditional aqueous electrolytes. In this work, PVA/PAA membranes were synthesized by the solvent casting method and soaked in 6 M KOH to act as GPEs. The thickness of the membrane was modified (50, 100, and 150 µm), and after determining the best thickness, the membrane was modified with synthesized SiO2 nanospheres and multi-walled carbon nanotubes (CNTs). SEM micrographs revealed that the CNTs displayed lengths of tens of micrometers, having a narrow diameter (95 ± 7 nm). In addition, SEM revealed that the SiO2 nanospheres had homogeneous shapes with sizes of 110 ± 10 nm. Physicochemical experiments revealed that SiO2 incorporation at 5 wt.% increased the water uptake of the PVA/PAA membrane from 465% to 525% and the ionic conductivity to 170 mS cm-1. The further addition of 0.5 wt.% CNTs did not impact the water uptake but it promoted a porous structure, increasing the power density and the stability, showing three-times-higher rechargeability than the ZAB operated with the PVA/PAA GPE.

2.
Brain Sci ; 14(9)2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39335349

RESUMO

Ideomotor apraxia is a cognitive disorder most often resulting from acquired brain lesions (i.e., strokes or tumors). Neuroimaging and lesion studies have implicated several brain regions in praxis and apraxia, but most studies have described (sub)acute patients. This study aimed to extend previous research by analyzing data from 115 left hemisphere chronic stroke patients using the praxis subtest of the Western Aphasia Battery, which is divided into four action types: facial, upper limb, complex, and instrumental. Lesion-symptom mapping was used to identify brain regions most critically associated with difficulties in each of the four subtests. Complex and instrumental action deficits were associated with left precentral, postcentral, and superior parietal gyri (Brodmann areas 2, 3, 4, 5, and 6), while the facial and upper limb action deficits maps were restricted to left inferior, middle, and medial temporal gyri (Brodmann areas 20, 21, 22, and 48). We discuss ideas about neuroplasticity and cortical reorganization in chronic stroke and how different methodologies can reveal different aspects of lesion and recovery networks in apraxia.

3.
Public Health ; 235: 56-62, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39047526

RESUMO

OBJECTIVES: The aim of this study was to investigate the longitudinal association of sleep with physical performance in a representative sample of non-institutionalised older adults residing in the municipality of São Paulo, Brazil. STUDY DESIGN: Prospective cohort study. METHODS: The current longitudinal study used data extracted from the Health, Well-being, and Aging Study (Estudo Saúde Bem-Estar e Envelhecimento [SABE]). The study population consisted of individuals aged ≥60 years who participated in the study in 2010 or 2015. Dependent variables included the Short Physical Performance Battery (SPPB) and gait speed. Independent variables of interest were self-reported sleep difficulty, daytime sleepiness and sleep quality. The longitudinal association between sleep variables and the outcomes was evaluated using Generalised Estimating Equations (GEE) Models adjusted for covariates. All the variables, except age, sex and schooling, were assessed at baseline and follow-up visits (2010 and 2015). RESULTS: The analyses included 2205 observations from 1559 individuals. The population mean age was 72 years in 2010 and 71 years in 2015, with a higher prevalence of women in both years. Between 2010 and 2015, there was a decline in the SPPB score and gait speed. Daytime sleepiness was negatively associated with the SPPB score [Coef.: -0.38 (95% confidence interval {CI}: -0.56, -0.21)] and gait speed [Coef.: -0.03 (95% CI: -0.05, -0.01)]. Poor sleep quality was negatively associated with the SPPB score [Coef.: -0.29 (95% CI: -0.57, -0.01)] and gait speed [Coef.: -0.03 (95% CI: -0.06, -0.00)]. CONCLUSIONS: Daytime sleepiness and poor sleep quality are associated with compromised physical performance in non-institutionalised older adults, and this association remained consistent over time.


Assuntos
Desempenho Físico Funcional , Qualidade do Sono , Humanos , Feminino , Masculino , Brasil/epidemiologia , Idoso , Estudos Longitudinais , Estudos Prospectivos , Pessoa de Meia-Idade , Velocidade de Caminhada , Idoso de 80 Anos ou mais
4.
J Phys Act Health ; 21(7): 692-697, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38626896

RESUMO

BACKGROUND: Walking activity has been associated with reduction in the development of chronic disease, cognitive and physical function impairment, disability, and mortality. The objective of this study was to examine the relationship between walking activity and physical function over 9 years of follow-up among Mexican Americans aged 78 years and older. METHODS: Participants (N = 998) were from the Hispanic Established Population for the Epidemiologic Study of the Elderly (2007-2016). Measures included walking activity duration and frequency, socio-demographics, body mass index, medical conditions, pain, depressive symptoms, limitation in activities of daily living, and the Mini-Mental State Examination. Low physical function was defined as scoring <7 on the Short Physical Performance Battery. At baseline, participants were grouped into nonwalkers (n = 653), walked <150 minutes/week (n = 144), and walked 150 minutes/week or more (n = 201). A Generalized Estimating Equation model was used to estimate the odds ratio and 95% CI of low physical performance as a function of walking activity status. RESULTS: Compared with nonwalkers, participants walking < 150 minutes/week had lower odds (odds ratio = 0.66, 95% CI, 0.51-0.86) of low physical function over time, after controlling for all covariates, as did those walking ≥ 150 minutes/week (odds ratio = 0.54, 95% CI, 0.41-0.71). CONCLUSIONS: Mexican American older adults who engage in any walking activity are at reduced risk of low physical function, even those with disability. Interventions at the individual and community level are recommended to reduce physical function impairment, even in those with preexisting medical conditions or disability.


Assuntos
Atividades Cotidianas , Americanos Mexicanos , Caminhada , Humanos , Idoso , Feminino , Masculino , Idoso de 80 Anos ou mais , Seguimentos , Desempenho Físico Funcional , Índice de Massa Corporal
5.
Small ; 20(31): e2306895, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38607269

RESUMO

Lithium-oxygen batteries show promising energy storage potential with high theoretical energy density; however, further investigation of chemical reactions is required. In this study, experimental Raman and theoretical analyzes are performed for a Li-O2 battery with LiClO4/dimethyl sulfoxide (DMSO) electrolyte and carbon cathode to understand the role of intermediate species in the reactional mechanism of the cell using a high donor number solvent. Operando Raman results reveal reversible changes in the DMSO bands, in addition to the formation and decomposition of Li2O2. On discharge, a decrease in DMSO polarizability is observed and bands of DMSO-Li+-anion interactions are evidenced and supported by ab initio density functional theory (DFT) calculations. Molecular dynamics (MD) force field simulations and operando Raman show that DMSO interacts with LiO2(sol), highlighting the stability of the electrolyte compared to the interaction with reactive O 2 - ${\rm O}_2^{-}$ . On charging, the presence of Li+ indicates the formation of a lithium-deficient phase, followed by the release of Li+ and oxygen. Therefore, this study contributes to understanding the discharge/charge chemistry of a Li-O2 cell, employing a common carbon cathode and DMSO electrolyte. The combination of a simple characterization technique in operando mode and theoretical studies provides essential information on the mechanism of Li-O2 system.

6.
Pathogens ; 13(2)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38392908

RESUMO

The long-term neurodevelopmental effects of antenatal Zika virus (ZIKV) exposure in children without congenital Zika syndrome (CZS) remain unclear, as few children have been examined to the age of school entry level. A total of 51 Colombian children with antenatal ZIKV exposure without CZS and 70 unexposed controls were evaluated at 4-5 years of age using the Behavior Rating Inventory of Executive Function (BRIEF), the Pediatric Evaluation of Disability Inventory (PEDI-CAT), the Bracken School Readiness Assessment (BSRA), and the Movement Assessment Battery for Children (MABC). The mean ages at evaluation were 5.3 and 5.2 years for cases and controls, respectively. Elevated BRIEF scores in Shift and Emotional Control may suggest lower emotional regulation in cases. A greater number of cases were reported by parents to have behavior and mood problems. BSRA and PEDI-CAT activity scores were unexpectedly higher in cases, most likely related to the COVID-19 pandemic and a delayed school entry among the controls. Although PEDI-CAT mobility scores were lower in cases, there were no differences in motor scores on the MABC. Of 40 cases with neonatal neuroimaging, neurodevelopment in 17 with mild non-specific findings was no different from 23 cases with normal neuroimaging. Normocephalic children with ZIKV exposure have positive developmental trajectories at 4-5 years of age but differ from controls in measures of emotional regulation and adaptive mobility, necessitating continued follow-up.

7.
Molecules ; 29(2)2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38257307

RESUMO

In this study, we address the ecological challenges posed by automotive battery recycling, a process notorious for its environmental impact due to the buildup of hazardous waste like foundry slag. We propose a relatively cheap and safe solution for lead removal and recovery from samples of this type of slag. The analysis of TCLP extracts revealed non-compliance with international regulations, showing lead concentrations of up to 5.4% primarily in the form of anglesite (PbSO4), as detected by XRF/XRD. We employed deep eutectic solvents (DES) as leaching agents known for their biodegradability and safety in hydrometallurgical processing. Five operational variables were systematically evaluated: sample type, solvent, concentration, temperature, and time. Using a solvent composed of choline chloride and glycerin in a 2:1 molar ratio, we achieved 95% lead dissolution from acidic samples at 90 °C, with agitation at 470 rpm, a pulp concentration of 5%, and a 5 h duration. Furthermore, we successfully recovered 55% of the lead in an optimized solution using an electrowinning cell. This research demonstrates the ability of DES to decontaminate slag, enabling compliance with regulations, the recovery of valuable metals, and new possibilities for the remaining material.

8.
J Med Life ; 16(7): 1017-1021, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37900065

RESUMO

In this retrospective study, we aimed to evaluate the effects of the neurotrophic compound Cerebrolysin on executive, cognitive, and functional performance in patients with traumatic brain injury (TBI) with a highly severe disability level. A total of 44 patients were included in the study, with 33 patients in the control group and 11 patients in the interventional group who received intravenous infusions of 30 mL Cerebrolysin. Both groups received standard rehabilitation therapy following the rehabilitation protocol for patients with TBI at Hospital Clínico Mutual de Seguridad. Functional and cognitive scales were evaluated at baseline, at four months, and at the endpoint of the intervention therapy at seven months (on average). The results revealed a significant improvement in the Cerebrolysin-treated group compared to the control group. Specifically, patients who received Cerebrolysin showed a moderate residual disability and a significant reduction in the need for care. Concerning the promising results and considering the limitations of the retrospective study design, we suggest that randomized controlled studies be initiated to corroborate the positive findings for Cerebrolysin in patients with moderate to severe brain trauma.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Humanos , Estudos Retrospectivos , Lesões Encefálicas/reabilitação , Lesões Encefálicas Traumáticas/tratamento farmacológico , Cognição , Recuperação de Função Fisiológica
9.
Nanomaterials (Basel) ; 13(18)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37764586

RESUMO

The electrochemical ion pumping device is a promising alternative for the development of the industry of recovering metals from natural sources-such as seawater, geothermal water, well brine, or reverse osmosis brine-using electrochemical systems, which is considered a non-evaporative process. This technology is potentially used for metals like Li, Cu, Ca, Mg, Na, K, Sr, and others that are mostly obtained from natural brine sources through a combination of pumping, solar evaporation, and solvent extraction steps. As the future demand for metals for the electronic industry increases, new forms of marine mining processing alternatives are being implemented. Unfortunately, both land and marine mining, such as off-shore and deep sea types, have great potential for severe environmental disruption. In this context, a green alternative is the mixing entropy battery, which is a promising technique whereby the ions are captured from a saline natural source and released into a recovery solution with low ionic force using intercalation materials such as Prussian Blue Analogue (PBA) to store cations inside its crystal structure. This new technique, called "electrochemical ion pumping", has been proposed for water desalination, lithium concentration, and blue energy recovery using the difference in salt concentration. The raw material for this technology is a saline solution containing ions of interest, such as seawater, natural brines, or industrial waste. In particular, six main ions of interest-Na+, K+, Mg2+, Ca2+, Cl-, and SO42--are found in seawater, and they constitute 99.5% of the world's total dissolved salts. This manuscript provides relevant information about this new non-evaporative process for recovering metals from aqueous salty solutions using hexacianometals such as CuHCF, NiHCF, and CoHCF as electrodes, among others, for selective ion removal.

10.
Environ Sci Pollut Res Int ; 30(48): 106260-106275, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37726624

RESUMO

This study aims to predict the potential for secondary lead recovery from motorcycle batteries in Brazil, since this is considered the second largest category of automobiles in the country. To achieve this objective, a forecasting model based on the ARIMA methodology was applied, with input data taken from Brazilian sectorial platforms. Furthermore, an analysis of the data, of the residuals, autocorrelation tests, as well as Kolmogorov-Smirnov and Dickey-Fuller tests, were performed. The SARIMA model (3,1,0) (2,0,0)12 presented a better adaptation to the behavior of the series. The results showed that the amount of secondary lead obtained based on the forecast model will be 89,972,842.08 million tons between 2021 and 2030 (14 million tons of lead originated only from motorcycle LABs in 2021). These results show a possible insufficiency of the installed capacity to supply the amount of lead to be processed in the country, not to mention the LABs from other vehicles (light and heavy) and other emerging battery technologies from electric vehicles. In addition, an analysis was conducted on the importance of secondary lead for the economy and the dangers of illegal recycling in Brazil. In general, this study contributes to the understanding of the importance of secondary production of lead in Brazil, an important asset for a country that does not have sufficient primary production for its domestic demand. The findings may assist in several alternatives for the proper planning and management of the collection, disposal and recycling of lead, providing the Brazilian government with directions for the development of new policies related to lead recycling.


Assuntos
Motocicletas , Gerenciamento de Resíduos , Brasil , Chumbo , Fontes de Energia Elétrica , Reciclagem/métodos , Previsões , Gerenciamento de Resíduos/métodos
11.
Arq. neuropsiquiatr ; Arq. neuropsiquiatr;81(9): 835-843, Sept. 2023.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1520252

RESUMO

Abstract The present review attempts to discuss how some of the central concepts from the Lurian corpus of theories are relevant to the modern neuropsychology of epilepsy and epilepsy surgery. Through the lenses of the main Lurian concepts (such as the qualitative syndrome analysis), we discuss the barriers to clinical reasoning imposed by quadrant-based views of the brain, or even atheoretical, statistically-based and data-driven approaches. We further advice towards a systemic view inspired by Luria's clinical work and theorizing, given their importance towards our clinical practice, by contrasting it to the modular views when appropriate. Luria provided theory-guided methods of assessment and rehabilitation of higher cortical functions. Although his work did not specifically address epilepsy, his theory and clinical approaches actually apply to the whole neuropathology spectrum and accounting for the whole panorama of neurocognition. This holistic and systemic approach to the brain is consistent with the network approach of the neuroimaging era. As to epilepsy, the logic of cognitive functions organized into complex functional systems, contrary to modular views of the brain, heralds current knowledge of epilepsy as a network disease, as well as the concept of the functional deficit zone.


Resumo A presente revisão tenta discutir como alguns dos conceitos centrais do corpus de teorias lurianas são relevantes para a moderna neuropsicologia da epilepsia e cirurgia da epilepsia. Através das lentes dos principais conceitos lurianos (como a análise qualitativa de síndromes), discutimos as barreiras ao raciocínio clínico impostas por visões do cérebro baseadas em quadrantes, ou mesmo abordagens ateóricas, baseadas em estatísticas e orientadas por dados. Aconselhamos ainda uma visão sistêmica inspirada na clínica e na teorização de Luria, dada sua importância para nossa prática clínica, contrastando-a com as visões modulares quando apropriado. Luria forneceu métodos teóricos de avaliação e reabilitação de funções corticais superiores. Embora seu trabalho não abordasse especificamente a epilepsia, sua teoria e abordagens clínicas na verdade se aplicam a todo o espectro da neuropatologia e respondem por todo o panorama da neurocognição. Essa abordagem holística e sistêmica do cérebro é consistente com a abordagem de rede da era da neuroimagem. Quanto à epilepsia, a lógica das funções cognitivas organizadas em sistemas funcionais complexos, ao contrário das visões modulares do cérebro, anuncia o conhecimento atual da epilepsia como uma doença em rede, bem como o conceito de zona de déficit funcional.

12.
Sensors (Basel) ; 23(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37299739

RESUMO

Technology in electric vehicles has increased substantially in the past decade. Moreover, it is projected to grow at record highs in the coming years since these vehicles are needed to reduce the contamination related to the transportation sector. One of the essential elements of an electric car is its battery, due to its cost. Batteries comprise parallel and series-connected cell arrangements to meet the power system requirements. Therefore, they require a cell equalizer circuit to preserve their safety and correct operation. These circuits keep a specific variable of all cells, such as the voltage, within a particular range. Within cell equalizers, capacitor-based ones are very common as they have many desirable characteristics of the ideal equalizer. In this work, an equalizer based on the switched-capacitor is proposed. A switch is added to this technology that allows the disconnection of the capacitor from the circuit. In this way, an equalization process can be achieved without excess transfers. Therefore, a more efficient and faster process can be completed. In addition, it allows another equalization variable to be used, such as the state of charge. This paper studies the operation, power design, and controller design of the converter. Moreover, the proposed equalizer was compared to other capacitor-based architectures. Finally, simulation results were presented to validate the theoretical analysis.


Assuntos
Fontes de Energia Elétrica , Eletricidade , Simulação por Computador , Tecnologia , Meios de Transporte
13.
Rev. Inst. Med. Trop ; 18(1)jun. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1449251

RESUMO

Introducción: la esclerosis múltiple (EM), enfermedad crónica del sistema nervioso (SNC), compromete significativamente la cognición. Su prevalencia en Paraguay es 9,2/100.000 habitantes, 72% con recaída remisión (EMRR) e incidencia de 2-3mujeres/hombre, afecta más a personas en edad productiva, con altos costos económicos y afectivos. Objetivos: caracterizar al paciente con EMRR, evaluar sus funciones ejecutivas (FEs) con BaNFE-2; establecer valores de corte ajustados al país. Metodología: con fundamento en teoría de la neurociencia cognitiva, diseño no experimental, cuantitativo, descriptivo, empírico, retrospectivo y transversal; técnica psicométrica y entrevista neuropsicológica en una muestra por conveniencia de 40 pacientes, 82,5% mujeres y edad 25-55 años (37,78±7,89). Resultados: se reportaron datos demográficos y clínicos, se caracterizaron las escalas de BaNFE-2 cuya consistencia interna resultó significativa. Se obtuvo 52,5% de alteración en la escala prefrontal y 42,5% en FEs; relaciones significativas con escolaridad, discapacidad física (DF), cantidad de brotes y deterioro cognitivo (DC); diferencias significativas por sexo, escolaridad, DF y DC. Se calcularon puntuaciones tipificadas por escolaridad, z<-1 establece el corte entre normalidad y alteración. Conclusión: las pruebas de BaNFE-2 perfilan la afectación del tiempo de ejecución, atención, memoria de trabajo y FEs. Este estudio aporta baremos ajustados al país y abre una novedosa línea de investigación aplicando BaNFE-2 en EM.


Introduction: Multiple sclerosis (MS) is a chronic, neurodegenerative, inflammatory disease of the central nervous system (CNS) that significantly compromises cognitive functions. In Paraguay, it occurs with a prevalence of 9.2/100,000 inhabitants, 72% in the clinical form of relapsing remission (RRMS) and an incidence of 2 to 3 women/men, affecting more people of productive age with high economic and emotional costs. Objectives: To characterize the Paraguayan patient with RRMS, to assess the state of their executive functions (EFs) with the BaNFE-2 battery, and to establish cut-off values adjusted to the country. Methods: Research based on the theory of cognitive neuroscience of non-experimental, quantitative and descriptive design for analytical purposes. It is empirical, retrospective and cross-sectional. The psychometric technique and neuropsychological interview were used in a convenience sample of 40 patients aged 25 to 55 (37.78 ± 7.89) and 82.5% women. Results: Demographic and clinical data of the participants were reported. The BaNFE-2 coded and normalized scales were statistically characterized, the internal consistency of which was significant. 52.5% of the alteration was obtained in the anterior prefrontal scale and 42.5% in FEs; there are significant relationships with schooling, physical disability (PD), number of outbreaks and cognitive impairment (CI); there were also significant differences by sex, education, PD and CI. Standardized scores adjusted for schooling were calculated such that z<-1 establishes the cutoff between normality and abnormality. Conclusion: BaNFE-2 battery tests profile the affectation of execution time, attention, working memory, and FEs. This study provides the adjusted scales for the country and opens a new line of research applying the BaNFE-2 battery in people with MS.

14.
Sensors (Basel) ; 23(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36991633

RESUMO

Nowadays, the use of renewable, green/eco-friendly technologies is attracting the attention of researchers, with a view to overcoming recent challenges that must be faced to guarantee the availability of Electric Vehicles (EVs). Therefore, this work proposes a methodology based on Genetic Algorithms (GA) and multivariate regression for estimating and modeling the State of Charge (SOC) in Electric Vehicles. Indeed, the proposal considers the continuous monitoring of six load-related variables that have an influence on the SOC (State of Charge), specifically, the vehicle acceleration, vehicle speed, battery bank temperature, motor RPM, motor current, and motor temperature. Thus, these measurements are evaluated in a structure comprised of a Genetic Algorithm and a multivariate regression model in order to find those relevant signals that better model the State of Charge, as well as the Root Mean Square Error (RMSE). The proposed approach is validated under a real set of data acquired from a self-assembly Electric Vehicle, and the obtained results show a maximum accuracy of approximately 95.5%; thus, this proposed method can be applied as a reliable diagnostic tool in the automotive industry.

15.
Polymers (Basel) ; 15(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36987228

RESUMO

Due to the energy requirements for various human activities, and the need for a substantial change in the energy matrix, it is important to research and design new materials that allow the availability of appropriate technologies. In this sense, together with proposals that advocate a reduction in the conversion, storage, and feeding of clean energies, such as fuel cells and electrochemical capacitors energy consumption, there is an approach that is based on the development of better applications for and batteries. An alternative to commonly used inorganic materials is conducting polymers (CP). Strategies based on the formation of composite materials and nanostructures allow outstanding performances in electrochemical energy storage devices such as those mentioned. Particularly, the nanostructuring of CP stands out because, in the last two decades, there has been an important evolution in the design of various types of nanostructures, with a strong focus on their synergistic combination with other types of materials. This bibliographic compilation reviews state of the art in this area, with a special focus on how nanostructured CP would contribute to the search for new materials for the development of energy storage devices, based mainly on the morphology they present and on their versatility to be combined with other materials, which allows notable improvements in aspects such as reduction in ionic diffusion trajectories and electronic transport, optimization of spaces for ion penetration, a greater number of electrochemically active sites and better stability in charge/discharge cycles.

16.
Membranes (Basel) ; 13(2)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36837626

RESUMO

Water polluted by discarded heavy metals such as lead is creating a global pollution problem. In this work, adsorption of Pb(II) was realized in batch studies by a hybrid membrane of cellulose acetate with ZnO particles. First, ZnO particles were prepared by precipitation and immobilized on the membrane. The hybrid membrane was elaborated by interfacial polymerization. The structure and surface were characterized based on Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). Batch experiments were carried out under different conditions where the number of particles of ZnO present in the membrane and the pH of the aqueous solution were varied. The Langmuir and Freundlich isotherm models were evaluated in the best adsorption conditions. Data fitted well with a Langmuir model with a maximum adsorption capacity of 15.55 mg·g-1, which was similar for this type of materials. Thermodynamic parameters such as Gibbs free energy, enthalpy, and entropy showed that the process was spontaneous and favorable. The hybrid membrane was evaluated in simulated wastewater of the battery industry with a superior efficiency of up to 97%; without the medium, it did not generate interference. These results suggest that Pb(II) removal by hybrid membrane is possible.

17.
Emergent Mater ; 6(1): 147-158, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36597484

RESUMO

Biocides are employed to prevent biodeterioration in waterborne paints. In the present study, we used zinc oxide nanoparticles (obtained from spent alkaline batteries) as biocide for indoor waterborne paint at 1.5% of the total solid content in paint. Two different zinc oxides synthesized from spent alkaline batteries, which showed photocatalyst activity, were employed as an antimicrobial agents. After leaching the anode of alkaline batteries, zinc was precipitated from the leachate liquor by introducing oxalic acid (O-ZnO) or sodium carbonate (C-ZnO). The antimicrobial properties of the prepared oxides were tested against Staphylococcus aureus (bacteria), Chaetomium globosum, and Aspergillus fumigatus (fungi) using agar well diffusion method. C-ZnO inhibited the growth of all the strains studied and presented enhanced activity than O-ZnO. The better performance as antimicrobial agent of C-ZnO compared to O-ZnO was attributed to its lower crystallite size, higher amount of oxygen monovacancies, and to its lower band gap energy. The oxide with the best performance in antimicrobial activity, C-ZnO, was employed for the formulation of waterborne acrylic paints. It was observed that 1.5% C-ZnO improved the antifungal properties and antibacterial properties compared to the control sample.

18.
Materials (Basel) ; 15(24)2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36556663

RESUMO

Nowadays, the use of biomass to produce cathode materials for lithium-sulfur (Li-S) batteries is an excellent alternative due to its numerous advantages. Generally, biomass-derived materials are abundant, and their production processes are environmentally friendly, inexpensive, safe, and easily scalable. Herein, a novel biomass-derived material was used as the cathode material in Li-S batteries. The synthesis of the new carbonaceous materials by simple carbonization and washing of water kefir grains, i.e., a mixed culture of micro-organisms, is reported. The carbonaceous materials were characterized morphologically, texturally and chemically by using scanning electron microscopy, N2 adsorption-desorption, thermogravimetric analysis, X-ray diffraction, and both Raman and X-ray photoelectron spectroscopy. After sulfur infiltration using the melt diffusion method, a high sulfur content of ~70% was achieved. Results demonstrated that the cell fitted with a cathode prepared following a washing step with distilled water after carbonization of the water kefir grains only, i.e., not subjected to any chemical activation, achieved good electrochemical performance at 0.1 C. The cell reached capacity values of 1019 and 500 mAh g-1 sulfur for the first cycle and after 200 cycles, respectively, at a high mass loading of 2.5 mgS cm-2. Finally, a mass loading study was carried out.

19.
Waste Manag ; 154: 49-63, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36209718

RESUMO

The Brazilian National Solid Waste Policy (BNSWP) determines that reverse logistics (RL) of waste batteries is mandatory and adopts the principle of shared responsibility among stakeholders. In this work, we sought to diagnose the current state of the RL chain for batteries in Vale do Aço, Brazil, and identify challenges and potentialities related to its improvement. Data were obtained by means of questionnaires sent to the main stakeholders involved in the batteries RL chain and by consultation of official Brazilian databases. The results showed that the main obstacles to the implementation of the RL of portable batteries in the region are: the lack of information by consumers and retailers regarding the BNSWP and management of waste batteries; the existence of few collection and consolidation points in the region; lack of municipal waste management plans; and lack of sustainability of waste picker organizations. The identified potentialities were: the good receptivity of environmental education actions by the population; the possibility of taking advantage of direct logistics of local retail chains to collect waste; the existence of a special waste management and transportation company in the region; and the existence of waste picker organizations interested in integrating the RL system. Finally, by a SWOT analysis, strategies for the implementation of a more effective RL system were drawn up. This work can serve as a basis for the structuring and implementation of the batteries RL system at the Metropolitan Region of Vale do Aço (MRVA) and can be a reference for other settings.

20.
ACS Appl Mater Interfaces ; 14(41): 47262-47271, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36205921

RESUMO

First-principles calculations within DFT have been performed to investigate the use of a recently synthesized form of silicene, the dumbbell (DB) silicene as an anode material for Li-ion batteries (LiBs). The energetically most stable geometries for Li adsorption on DB silicene were investigated, and the energy barriers for Li-ion diffusion among the possible stable adsorption sites were calculated. We found that DB silicene can be lithiated up to a ratio of 1.05 Li per Si atom, resulting in a high storage capacity of 1002 mA h g-1 and an average open-circuit potential of 0.38 V, which makes DB silicene suitable for applications as an anode in LiBs. The energy barrier for Li-ion diffusion was calculated to be as low as 0.19 eV, suggesting that the Li ions can easily diffuse on the entire DB silicene surface, decreasing the time for the charge/discharge process of the LiBs. Our detailed investigations show that the most stable form of two-dimensional silicon has characteristic features suitable for application in high-performance LiBs.

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