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1.
J Phys Chem Lett ; 14(1): 107-115, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36574224

RESUMO

Kesterite Cu2ZnSn(S,Se)4 (CZTSSe) solar absorbers have attracted intensive investigations for next-generation photovoltaic applications. Here, by using ab initio static and molecular dynamics simulations, we investigated the anion compositional dependence of electron-vibration interaction in CZTSSe materials. We found that the conduction band fluctuates more than the valence band, and as a result, the band gap variation is more sensitive to the change of the former, which can be understood in terms of p-d hybridization in the valence bands. Electron-phonon coupling is smaller in CZTSSe alloy compared to pure S- or Se-containing structures, as evidenced by the smaller fluctuation of excitation energy, and can be attributed to the weaker structural dynamics of the metal-anion bond. Small electron-phonon coupling strength may lead to better charge transport in these materials. We also elucidated the interplay between disordered structures and S/Se stoichiometry through analysis of optical line width. The results highlight the importance of anion composition engineering and provide new insights into the rational design of high-performing kesterite absorbers for solar cells.

2.
J Food Drug Anal ; 27(3): 623-631, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31324279

RESUMO

Trillions of microbes have evolved with and continue to live on human beings. With the rapid advances in tools and technology in recent years, new knowledge and insight in cross-talk between the microbes and their hosts have gained. It is the aim of this work to critically review and summarize recent literature reports on the role of microbiota and mechanisms involved in the progress and development of major human diseases, which include obesity, hypertension, cardiovascular disease, diabetes, cancer, Inflammatory Bowel Disease (IBD), gout, depression and arthritis, as well as infant health and longevity.


Assuntos
Microbioma Gastrointestinal , Saúde do Lactente , Neoplasias/metabolismo , Artrite/metabolismo , Doenças Cardiovasculares/metabolismo , Depressão/metabolismo , Diabetes Mellitus/metabolismo , Gota/metabolismo , Humanos , Hipertensão/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Obesidade/metabolismo
3.
Zhongguo Zhong Yao Za Zhi ; 44(13): 2799-2805, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31359693

RESUMO

To establish and validate the design space of the Digeda-4 flavored decoction( DGD-4D) extraction process by using the quality by design( Qb D) concept. With DGD-4D decoction pieces as a model drug,with the transfer rate of aesculin,picroside I,picroside Ⅱ,geniposide and the yield of extract as critical quality attributes( CQAs),the single factor experiment design was used to determine the level of each factor; the Plackett-Burman experiment design was used to select the critical process parameters( CPPs);and the Box-Behnken experiment design was used to optimize the extraction process. The design space of the DGD-4D extraction process was established,and finally,four experimental points were selected to verify the established model. The single factor experiment determined the levels of each factor,including soaking time 60 min and 30 min,water adding volume 12 times and 8 times,extraction time 90 min and 30 min,number of extraction times 3 times and 1 time,as well as extraction temperature 100 ℃ and 90 ℃.By Plackett-Burman experimental design,the DGD-4D water addition,extraction time and number of extraction times were determined to be CPPs. The Box-Behnken experimental variance analysis showed that P of the regression model was less than 0. 01 and the misstated value was more than 0. 01,indicating that the model had good predictive ability,and the operation space of CPPs in the DGD-4D extraction process was determined as follows: the amount of water addition was 10-12 times; extraction time 50-80 min; and number of extraction times was 3 times. The design space of DGD-4D extraction process based on the concept of Qb D is conducive to improving the stability of product quality and laying a foundation for the future development of DGD-4D.


Assuntos
Química Farmacêutica/métodos , Medicamentos de Ervas Chinesas/química , Projetos de Pesquisa
4.
Zhongguo Zhong Yao Za Zhi ; 43(19): 3962-3969, 2018 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-30453724

RESUMO

To establish the high performance liquid chromatography (HPLC) fingerprint for Digeda-4 decoction (DGD-4D), determine the contents of aesculetin, geniposide, picroside Ⅰ, picroside Ⅱ and ellagicacid in DGD-4D, and provide the scientific foundation for quality control of DGD-4D. The analysis was performed on Diamonsil(2) C18 (4.6 mm×250 mm,5 µm) column, with methanol-0.1% phosphoric acid aqueous solution as mobile phase for gradient elution. The flow rate was 1.0 mL·min⁻¹; injection size was 10 µL; temperature was maintained at 30 °C, and the detection wavelength was set at 254 nm. The common mode of DGD-4D HPLC fingerprint was established, and the hidden information was analyzed by Chemometrics. Chromatographic peaks for DGD-4D were identified by HPLC and quantitative analysis was conducted for characteristic peaks. There were 17 common peaks in the fingerprints and the similarity of the fingerprints was over 0.9 in all 15 batches. The samples were broadly divided into four kinds by principal component analysis and clustering analysis. Four marker compounds were verified by partial least squares discriminant analysis, and No. 9, 12 and 14 peaks were identified as geniposide, picroside Ⅱ, and picroside Ⅰ respectively. The average recoveries were in the range of 95.91%-97.31%. The HPLC fingerprint method for content determination is reliable, accurate, rapid, simple, and reproducible, and can be used as one of the effective methods to control the quality of DGD-4D.


Assuntos
Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/normas , Cromatografia Líquida de Alta Pressão , Cinamatos , Glucosídeos Iridoides , Iridoides , Metanol , Análise de Componente Principal , Controle de Qualidade
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