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1.
ChemSusChem ; : e202301808, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38507195

RESUMO

The rise in the energy demand, the need to decrease the use of fossil fuels, expanding investments in renewable energy and boosting the electric vehicle market, opens the door to new technologies in clean energy accumulators. Lithium-ion batteries are the most advanced technology in the market but have safety concerns due to the flammability of the electrolyte, which opens the door to innovations. One of these innovations is the solid-state batteries (SSB), which, by using solid electrolytes, do not have the flammable risk, bringing safety to users while reaching similar energy and power densities. This work presents a review about SSB, based on qualitative and exploratory research, using the Web of Science (WoS) platform. Keywords used to gather information from the database were "solid state batteries" and "electrolytes". Only publications from 2018 to 2023 were selected. The main research focus is to solve the challenges posed by the different physical-chemical phenomena of the SSB. This work focuses on the general comprehension of the SSB batteries, what are the factors that can affect it and the main solutions presented in the literature the last five years.

2.
Eval Program Plann ; 96: 102155, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36402596

RESUMO

The learning process for a Biology topic regarding organisms and animal kingdom diversity was investigated through an innovative Interactive Didactic Sequence (IDS) which integrated the idea of "concept maps" with the Hermeneutic-Dialectic Circle (HDC). HDC is a tool for data collection and a reference for pluralist-constructivist thinking, considered a form of fourth-generation evaluation. Hofstede's cultural dimensions were also integrated into the investigation in order to facilitate mediation in an evaluative context. Students' performances (N = 25) from a São Paulo-Brazil public school were statistically evaluated. Their cultural profile was determined via the Hofstede Value Survey Model 1994 questionnaire. The elaborative process of arranging concept maps was individual (CM-individual) and integrated with HDC in groups (CM-HDC). Concept map assessment methods were based off existing literature. An improvement in students' performances (p < 0.05) that presented concept maps integrated to HDC in a more complex structure when compared to individually-built maps was observed. Employment of HDC helped form motivational/interactive dialogues between students and teachers, which, in turn, assisted in achieving greater learning through the use of concept maps. The application of the fourth-generation evaluation was improved via knowledge regarding students' cultural profiles.


Assuntos
Aprendizagem , Instituições Acadêmicas , Brasil , Avaliação de Programas e Projetos de Saúde , Biologia
3.
Bioresour Technol ; 348: 126627, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34958907

RESUMO

The trend in the modern world is to replace fossil fuels with green energy sources in order to reduce their environmental impact. The biorefinery industry, within this premise, needs to establish quantitative and qualitative analytical methods to better understand lignocellulosic biomass composition and structure. This paper presents chemical techniques (chromatography, thermal analysis, HRMS, FTIR, NIR, and NMR) and physicochemical techniques (XRD, optical and electron microscopy techniques - Confocal fluorescence, Raman, SPM, AFM, SEM, and TEM) for the microstructural characterization of lignocellulosic biomass and its derivatives. Each of these tools provides different and complementary information regarding molecular and microstructural composition of lignocellulosic biomass. Understanding these properties is essential for the design and operation of associated biomass conversion processing facilities. PAT, monitored in real-time, ensures an economical and balanced mass-energy process. This review aimed to help researchers select the most suitable analytical technique with which to investigate biomass feedstocks with recalcitrant natures.


Assuntos
Biocombustíveis , Lignina , Biomassa , Combustíveis Fósseis , Lignina/química
4.
J Phys Condens Matter ; 30(17): 175401, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29546849

RESUMO

Realistic implementations of the Kitaev chain require, in general, the introduction of extra internal degrees of freedom. In the present work, we discuss the presence of hidden BDI symmetries for free Hamiltonians describing systems with an arbitrary number of internal degrees of freedom. We generalize results of a spinfull Kitaev chain to construct a Hamiltonian with n internal degrees of freedom and obtain the corresponding hidden chiral symmetry. As an explicit application of this generalized result, we exploit by analytical and numerical calculations the case of a spinful two-band Kitaev chain, which can host up to four Majorana bound states. We also observe the appearence of minigap states, when chiral symmetry is broken.

5.
Bioresour Technol ; 101(4): 1247-53, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19846294

RESUMO

Sugarcane bagasse was pretreated with diluted sulfuric acid to obtain sugarcane bagasse hemicellulosic hydrolysate (SBHH). Experiments were conducted in laboratory and semi-pilot reactors to optimize the xylose recovery and to reduce the generation of sugar degradation products, as furfural and 5-hydroxymethylfurfural (HMF). The hydrolysis scale-up procedure was based on the H-Factor, that combines temperature and residence time and employs the Arrhenius equation to model the sulfuric acid concentration (100 mg(acid)/g(dm)) and activation energy (109 kJ/mol). This procedure allowed the mathematical estimation of the results through simulation of the conditions prevailing in the reactors with different designs. The SBHH obtained from different reactors but under the same H-Factor of 5.45+/-0.15 reached similar xylose yield (approximately 74%) and low concentration of sugar degradation products, as furfural (0.082 g/L) and HMF (0.0071 g/L). Also, the highest lignin degradation products (phenolic compounds) were rho-coumarilic acid (0.15 g/L) followed by ferulic acid (0.12 g/L) and gallic acid (0.035 g/L). The highest concentration of ions referred to S (3433.6 mg/L), Fe (554.4 mg/L), K (103.9 mg/L). The H-Factor could be used without dramatically altering the xylose and HMF/furfural levels. Therefore, we could assume that H-Factor was directly useful in the scale-up of the hemicellulosic hydrolysate production.


Assuntos
Biotecnologia/métodos , Celulose/síntese química , Polissacarídeos/síntese química , Saccharum/química , Ácidos Sulfúricos/química , Análise de Variância , Celulose/química , Celulose/ultraestrutura , Hidrólise , Cinética , Modelos Químicos , Projetos Piloto , Temperatura , Fatores de Tempo , Xilose/análise
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