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To date, transforming environmental energy into electricity through a non-mechanical way is challenging. Herein, a series of photomechaelectric (PME) polyurethanes containing azobenzene-based photoisomer units and ionic liquid-based dipole units are synthesized, and corresponding PME nanogenerators (PME-NGs) to harvest electricity are fabricated. The dependence of the output performance of PME-NGs on the structure of the polyurethane is evaluated. The results show that the UV light energy can directly transduce into alternating-current (AC) electricity by PME-NGs via a non-mechanical way. The optimal open-circuit voltage and short-circuit current of PME-NGs under UV illumination reach 17.4 V and 696 µA, respectively. After rectification, the AC electricity can be further transformed into direct-current (DC) electricity and stored in a capacitor to serve as a power system to actuate typical microelectronics. The output performance of PME-NGs is closely related to the hard segment content of the PME polyurethane and the radius of counter anions in the dipole units. Kelvin probe force microscopy is used to confirm the existence of the PME effect and the detailed mechanism about the generation of AC electricity in PME-NGs is proposed, referring to the back and forth drift of induced electrons on the two electrodes in contact with the PME polyurethanes.
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The aromatization of light alkane is an important process for increasing the aromatic production and utilization efficiency of light alkane resources simultaneously. Herein, Ga-modified HZSM-5 catalysts were prepared and investigated by a series of characterization techniques such as X-ray diffraction, nuclear magnetic resonance spectroscopy, transmission electron microscopy, N2 adsorption-desorption, and NH3 temperature-programmed desorption to study their physicochemical properties. The catalytic performance in propane aromatization was also tested. Importantly, the structure-activity relationship, reaction pathway, and coke formation mechanism in propane aromatization were systematically explored. It was found that different Ga introduction methods would affect the amounts of Brønsted and Lewis acid sites, and Ga-HZSM-5 prepared by the hydrothermal method exhibited higher amounts of Brønsted and Lewis acid sites but a lower B/L ratio. As a result, Ga-HZSM-5 showed higher propane conversion and benzene, toluene, and xylene yield compared with that of Ga2O3/HZSM-5. The propane aromatization reaction pathway indicated that propane dehydrogenation to propene was a crucial step for aromatic formation. The increase of the Lewis acid density in Ga-HZSM-5 can effectively improve the dehydrogenation rate and promote the aromatization reaction. Furthermore, the formation of coke species was studied by thermogravimetry-mass spectrometry and Raman approaches, the results of which indicated that the graphitization degree of coke formed over spent Ga-HZSM-5 is lower, resulting in enhanced anticoking stability.
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BACKGROUND: Evidence indicates that the Sport Education Model (SEM) has demonstrated effectiveness in enhancing students' athletic capabilities and fostering their enthusiasm for sports. Nevertheless, there remains a dearth of comprehensive reviews examining the impact of the SEM on students' attitudes toward physical education learning. PURPOSE: The purpose of this review is to elucidate the influence of the SEM on students' attitudes toward physical education learning. METHODS: Employing the preferred reporting items of the Systematic Review and Meta-analysis (PRISMA) statement guidelines, a systematic search of PubMed, SCOPUS, EBSCOhost (SPORTDiscus and CINAHL Plus), and Web of Science databases was conducted in mid-January 2023. A set of keywords associated with the SEM, attitudes toward physical education learning, and students were employed to identify relevant studies. Out of 477 studies, only 13 articles fulfilled all the eligibility criteria and were consequently incorporated into this systematic review. The validated checklist of Downs and Black (1998) was employed for the assessment, and the included studies achieved quality scores ranging from 11 to 13. The ROBINS-I tool was utilized to evaluate the risk of bias in the literature, whereby only one paper exhibited a moderate risk of bias, while the remainder were deemed to have a high risk. RESULTS: The findings unveiled significant disparities in cognitive aspects (n = 8) and affective components (n = 12) between the SEM intervention and the Traditional Teaching (TT) comparison. Existing evidence suggests that the majority of scholars concur that the SEM yields significantly superior effects in terms of students' affective and cognitive aspects compared to the TT. CONCLUSIONS: Nonetheless, several issues persist, including a lack of data regarding junior high school students and gender differences, insufficient frequency of weekly interventions, inadequate control of inter-group atmosphere disparities resulting from the same teaching setting, lack of reasonable testing, model fidelity check and consideration for regulating variables, of course, learning content, and unsuitable tools for measuring learning attitudes. In contrast, the SEM proves more effective than the TT in enhancing students' attitudes toward physical learning. SYSTEMATIC REVIEW REGISTRATION: ( https://inplasy.com/ ) (INPLASY2022100040).
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Educação Física e Treinamento , Humanos , Esportes/psicologia , Estudantes/psicologia , Modelos Educacionais , Atitude , AprendizagemRESUMO
Pesticides have been used extensively in the field of plant protection to maximize crop yields. However, the long-term, unmanaged application of pesticides has posed severe challenges such as pesticide resistance, environmental contamination, risk in human health, soil degradation, and other important global issues. Recently, the combination of nanotechnology with plant protection strategies has offered new perspectives to mitigate these global issues, which has promoted a rapid development of NCs-based pesticides. Unlike certain conventional pesticides that have been applied inefficiently and lacked targeted control, pesticides delivered by nanocarriers (NCs) have optimized formulations, controlled release rate, and minimized or site-specific application. They are receiving increasing attention and are considered as an important part in sustainable and smart agriculture. This review discussed the limitation of traditional pesticides or conventional application mode, focused on the sustainable features of NCs-based pesticides such as improved formulation, enhanced stability under harsh condition, and controlled release/degradation. The perspectives of NCs-based pesticides and their risk assessment were also suggested in this view for a better use of NCs-based pesticides to facilitate sustainable, smart agriculture in the future.
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Agricultura , Portadores de Fármacos/química , Nanoestruturas/química , Controle de Pragas/métodos , Praguicidas/química , Quitosana/química , Praguicidas/metabolismo , RNA de Cadeia Dupla/química , RNA de Cadeia Dupla/metabolismo , SolubilidadeRESUMO
Metal-organic frameworks (MOFs) with long-term stability and reversible high water uptake properties can be ideal candidates for water harvesting and indoor humidity control. Now, a mesoporous and highly stable MOF, BIT-66 is presented that has indoor humidity control capability and a photocatalytic bacteriostatic effect. BIT-66 (V3 (O)3 (H2 O)(BTB)2 ), possesses prominent moisture tunability in the range of 45-60 % RH and a water uptake and working capacity of 71 and 55â wt %, respectively, showing good recyclability and excellent performance in water adsorption-desorption cycles. Importantly, this MOF demonstrates a unique photocatalytic bacteriostatic behavior under visible light, which can effectively ameliorate the bacteria and/or mold breeding problem in water adsorbing materials.
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Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Estruturas Metalorgânicas/farmacologia , Vanádio/farmacologia , Antibacterianos/química , Catálise , Teoria da Densidade Funcional , Umidade , Hidrólise , Luz , Estruturas Metalorgânicas/química , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Processos Fotoquímicos , Porosidade , Propriedades de Superfície , Vanádio/química , Água/químicaRESUMO
Purpose: The purpose of this study is to unveil the impact of metacognition on academic achievement in physical education and activity settings by conducting a comprehensive systematic literature review with a meta-analysis of qualitative findings. Patients and Methods: Systematic searches identified English-language, peer-reviewed journal articles reporting the results of qualitative or mixed-methods studies of the emerging themes of metacognition on academic achievement in sports. PubMed, Web of Science, Scopus, ProQuest, and SPORTDiscus were searched from inception to June 2023. Results: Data from 20 studies were included in the review. Thematic meta-analysis identified descriptive themes: 1) Metacognitive performance during the learning process in different sports disciplines; 2) Domains of metacognitive skills related to academic performance; 3) Self-regulation strategies related to academic performance; 4) Influencing factors of metacognition; 5) Metacognitive interventions on motor learning and academic performance. Generate an analytical theme based on five descriptive themes. Conclusion: In-depth descriptions of the emerging themes related to metacognition and academic performance during motor learning were provided by different students and athletes. The conclusions reported in the study align with the theoretical models of metacognition. The research findings will provide strategies for physical education teachers, coaches, and trainers to enhance both physical and academic performance.
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Interactions between polysaccharides and ionic liquids (ILs) at the molecular level are essential to elucidate the dissolution and/or plasticization mechanism of polysaccharides. Herein, saccharide-based ILs (SILs) were synthesized, and cellulose membrane was soaked in different SILs to evaluate the interactions between SILs and cellulose macromolecules. The relevant results showed that the addition of SILs into cellulose can effectively reduce the intra- and/or inter-molecular hydrogen bonds of polysaccharides. Glucose-based IL showed the intensest supramolecular interactions with cellulose macromolecules compared to sucrose- and raffinose-based ILs. Two-dimensional correlation and perturbation-correlation moving window Fourier transform infrared techniques were for the first time used to reveal the dynamic variation of the supramolecular interactions between SILs and cellulose macromolecules. Except for the typical HOâ¯H interactions of cellulose itself, stronger -Clâ¯HO hydrogen bonding interactions were detected in the specimen of SILs-modified cellulose membranes. Supramolecular interactions of -Clâ¯H, HOâ¯H, C-Clâ¯H, and -C=Oâ¯H between SILs and cellulose macromolecules sequentially responded to the stimuli of temperature. This work provides a new perspective to understanding the interaction mechanism between polysaccharides and ILs, and an avenue to develop the next-generation ILs for dissolving or thermoplasticizing polysaccharide materials.
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Líquidos Iônicos , Líquidos Iônicos/química , Imidazóis/química , Celulose/química , Polissacarídeos , TemperaturaRESUMO
It is still a big challenge to obtain hydrophobic thermoplastic starch with outstanding mechanical performance due to the inevitable usage of typical hydrophilic plasticizers like glycerol during processing. Herein, we report a novel hydrophobic thermoplastic starch using a supramolecularly induced thermoplasticization technique. To achieve this aim, a functional sucrose-based ionic liquid crystal (ILC) including numerous chloride atoms has been firstly synthesized, and the obtained ILC molecules are then used as supramolecular inducers to thermoplasticize corn starch granules. Thermoplasticity and hydrophobicity of the prepared supramolecularly induced thermoplastic starch (STPS) with different ILC contents have been extensively investigated. Mechanism of the supramolecularly induced thermoplasticization has been investigated using molecular simulation as well. The prepared STPS with the maximum tensile strength of 8.4 MPa and water contact angle of about 117° show large potential applications in green and sustainable packaging materials.
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To delicately track the Li-ion transport in SPEs under an external electric field (EF) is a big challenge, considering the limitation of most spectroscopic methods to monitor the real-time conformational changes and track the dynamic process. Herein, real-time Li-ion transition behavior and transport dynamics in typical poly(vinyl alcohol)/LiClO4 electrolytes under an external EF have been studied by combining time-resolved Fourier transform infrared (FTIR) with two-dimensional correlation FTIR spectroscopy. Results show that no migration of Li-ions has been detected when the time scale of the EF loading is at nanosecond (less than 200 ns). However, for the first time, Li-ions have been found to significantly transfer along the EF direction as the time scale enhances to microsecond order of magnitude and the migration period is less than 10 microseconds. The Li+ migration in the SPEs under an EF is a complicated process including quasi-periodic dissociation and coordination effects between Li-ion carriers and polymeric chains.
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Herein, we report a novel amphiphilic biodegradable and sustainable soybean oil-based copolymer (SBC) prepared by grafting hydrophilic and biocompatible hydroxyethyl acrylate (HEA) polymeric segments onto the natural hydrophobic soybean oil chains. FTIR, H(1)-NMR, and GPC measurements have been used to investigate the molecular structure of the obtained SBC macromolecules. Self-assembly behaviors of the prepared SBC in aqueous solution have also been extensively evaluated by fluorescence spectroscopy and transmission electron microscopy. The prepared SBC nanocarrier with the size range of 40 to 80 nm has a potential application in the biomedical field.
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Anti-clotting EDTA-diol was successfully synthesized by an esterification reaction between EDTA-2Na and poly(ethylene glycol). Novel anti-clotting and biodegradable multi-block polyurethanes were then prepared by EDTA-diol and biodegradable poly(1,4-butylene adipate glycol) (PBA) as the soft chain, and 1,4-butanediol (BDO) and hexamethylene diisocyanate (HDI) as the hard chain, respectively. The effect of the EDTA-diol content in the soft chain of the prepared polyurethanes on mechanical properties, thermal stability, hydrophilicity, and anticoagulant ability was largely investigated by tensile tests, thermogravimetric analysis, contact angle and water absorption measurements, and hemolytic measurement. Self-assembly behaviors of the resulting polyurethanes were also evaluated by fluorescence spectroscopy and transmission electron microscopy. The prepared polyurethanes have large potential applications in the fields of biomedical materials such as tissue engineering and drug carriers.
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Acrylic acid and styrene were polymerized onto monodispersed Fe3O4 nanoparticles using a grafting copolymerization method. Aniline molecules were then bonded onto the Fe3O4 nanoparticles by electrostatic self-assembly and further polymerized to obtain uniform polyaniline/Fe3O4 (PANI/Fe3O4) nanoparticles (approximately 35 nm). Finally, monodispersed Ag/PANI/Fe3O4 nanoparticles were prepared by an in situ reduction reaction between emeraldine PANI and silver nitrate. Fourier transform infrared and UV-visible spectrometers and a transmission electron microscope were used to characterize both the chemical structure and the morphology of the resulting nanoparticles.