Search

Your search keyword '"Ma, Yafei"' showing total 317 results
Start Over Author "Ma, Yafei"
317 results on '"Ma, Yafei"'

22. Common Mode Voltage Cancellation Method of PMSM Based on NPC Three Level Inverter

Author

Ma, Yafei, Jiang, Dong, Liu, Zicheng, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Tan, Kay Chen, Series Editor, Yang, Qingxin, editor, Dong, Xuzhu, editor, and Ma, Weiming, editor

Published
2023
Full Text
View/download PDF

37. Modified Chitosan Nanofiber Membrane Fabrication for Removal of Pb2+from Coptidis rhizomaDecoction

Author

Ma, Yafei, Yang, Ruobing, Liu, Xinman, Fu, Zhiping, Guo, Yuexin, Wang, Hui, Jia, Zhiqian, and Song, Chunxue

Abstract

Heavy metals in medicine are easily introduced during production and processing, and heavy metals pose a risk to human health. To realize the separation of heavy metals from medicine and provide a new method for removing heavy metals, in this study, ethylenediaminetetraacetic acid (EDTA) was used to modify chitosan, and the ethylenediaminetetraacetic acid-modified chitosan (CS-EDTA) fiber membrane was prepared through electrospinning to remove lead ions from Coptidis rhizomadecoction. The effects of spinning speed (0.1 mL/h), modification method (2 g Na2EDTA, 0.1 g EDC, 0.2 g NHS), and pH (pH = 5) on the adsorption capacity were studied. The results showed that the adsorption of Pb2+on the CS-EDTA membrane was pseudo-second-order kinetics model (R2> 0.999) and the Langmuir model (R2> 0.978). The kineticmaximum adsorption capacity of the CS-EDTA membrane was 116.2 mg·g–1. The Pb2+content in C. rhizomadecoction after adsorption meets the limit requirements for heavy metals specified in the traditional Chinese medicine standard (Pb2+≤ 5 mg·kg–1). The chemical composition of the decoction of C. rhizomadid not change significantly after the removal of Pb2+. The membrane has antibacterial properties against Gram-negative bacteria.

Published
2025
Full Text
View/download PDF

40. Sensitive and environmental friendly sensor on porphyrin functionalized chitosan fiber membrane for Hg2+.

Author

Ma, Yafei, Liu, Xinman, Fu, Zhiping, Zhang, Lifen, Guo, Yuexin, Wang, Hui, and Jia, Zhiqian

Subjects
CHINESE medicine, METAL detectors, HEAVY metals, POLLUTANTS, DETECTION limit
Abstract

Mercury is the most toxic and harmful heavy metal pollutant, and it is essential to detect and remove mercury from beverages. Inducing the porphyrin molecules into the chitosan structure, a novel membrane sensor tetrakis(4-carboxyphenyl)porphyrin-grafted chitosan fiber membrane (TCPP-CS) was prepared by electrospinning method and applied to recognize Hg2+ contaminant selectively. Compared with other common metal ions (Pb2+, Cu2+, Fe3+, Cr3+, Mg2+, and Zn2+), the colorimetric sensor has specific color development and sensitivity to Hg2+ and the detection limit of the sensor reaches 1 × 10−5 mol·L−1. The response time of the membrane is 5 s, and it can be specifically colored in various pH environments convenient for practical application. Hg2+ resulted in a visual color change of the fiber membrane from brown to yellow-green, indicating a potential interaction between the porphyrin-functionalized chitosan fiber membrane and Hg2+ ions, and the wavelength shift of the UV–visible spectrum can be observed. It has the advantages of simplicity, rapidity, high selectivity, and high sensitivity, providing a new method for removing and detecting heavy metals in traditional Chinese medicine and drinks. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results