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971.
Zhao Shiduo Li Qiming Li Fang Liang Zhihua 《Journal of Sol-Gel Science and Technology》2017,81(2):544-555
Journal of Sol-Gel Science and Technology - CuCo2O4 spinel nanoparticles were successfully preparedvia a sol–gel method, which were firstly employed in catalytic reduction of p-nitrophenol to... 相似文献
972.
Ying Tang Xiangjie Kong LiDe Fang Hongtao Wang 《Physica C: Superconductivity and its Applications》2011,471(23-24):1660-1663
Combined with the thermal analysis and phase identification, the influence of the B2O3 impurity in the original B powder on the phase formation of MgB2 during the sintering process was investigated. It is found that how the B2O3 impurity in the original B powder affects the sintering process of MgB2 depends on the reactivity of Mg particles in the original powder. If the Mg particles in the original powder are small and reactive enough, the B2O3 impurity could react with them before Mg melting during the sintering process and accelerate the solid–solid reaction between Mg and B. Otherwise, the B2O3 impurity could not react with Mg particles before Mg melting and depress the solid–solid reaction between Mg and B. 相似文献
973.
Qu Fengjin Ma Xiaoyan Hui Yuchen Chen Fang Gao Yan Chen Ying 《Journal of Solid State Electrochemistry》2017,21(6):1545-1557
Journal of Solid State Electrochemistry - As enzyme-immobilization and electron-transfer are the key factors for fabricating an enzymatic bioelectrode and its devices, we investigated a strategy to... 相似文献
974.
975.
δ-Glyconolactams were first synthesized by the intramolecular Schmidt–Boyer reaction using corresponding δ-azidosugars as starting material. The reaction could be efficiently performed in good yields of 61–69% under microwave radiation in acid condition, providing an alternative protocol to iminosugar δ-lactam. 相似文献
976.
Fen Yu Dr. Xuan Fang Huimin Jia Miaoxing Liu Xiaotong Shi Chaowen Xue Dr. Tingtao Chen Prof. Zhipeng Wei Prof. Fang Fang Prof. Hui Zhu Prof. Hongbo Xin Prof. Jing Feng Prof. Xiaolei Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(24):8053-8058
For the first time, the influence of different types of atoms (Zn and O) on the antibacterial activities of nanosized ZnO was quantitatively evaluated with the aid of a 3D‐printing‐manufactured evaluation system. Two different outermost atomic layers were manufactured separately by using an ALD (atomic layer deposition) method. Interestingly, we found that each outermost atomic layer exhibited certain differences against gram‐positive or gram‐negative bacterial species. Zinc atoms as outermost layer (ZnO?Zn) showed a more pronounced antibacterial effect towards gram‐negative E. coli (Escherichia coli), whereas oxygen atoms (ZnO?O) showed a stronger antibacterial activity against gram‐positive S. aureus (Staphylococcus aureus). A possible antibacterial mechanism has been comprehensively discussed from different perspectives, including Zn2+ concentrations, oxygen vacancies, photocatalytic activities and the DNA structural characteristics of different bacterial species. 相似文献
977.
978.
979.
Differentiating parts of Cinnamomum cassia using LC‐qTOF‐MS in conjunction with principal component analysis
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Pei‐Yi Chen Jhe‐Wei Yu Fen‐Ling Lu Mei‐Chih Lin Hwei‐Fang Cheng 《Biomedical chromatography : BMC》2016,30(9):1449-1457
Cinnamon bark (Rou Gui in Chinese), cinnamon twig (Gui Zhi) and shaved cinnamon bark (Gui Sin) have been widely used as spices and in traditional Chinese medicine since ancient times. On‐going issues related to quality and authenticity necessitate the development of analytical methods capable of providing an objective evaluation of samples. In this study, chemical fingerprints of cinnamon bark, cinnamon twigs and shaved cinnamon bark were established using liquid chromatography quadruple time‐of‐flight mass spectrometry in conjunction with principal component analysis (PCA). From 125 samples of cinnamon, we identified the following eight compounds and their the detection ratios: coumarin, cinnamaldehyde, cinnamyl alcohol, cinnamic acid, 2‐hydroxycinnamaldehyde, 2‐hydroxycinnamic acid, 2‐methoxycinnamaldehyde and 4‐methoxycinnamaldehyde. Of these, 4‐methoxycinnamaldehyde presented the largest variations in detection ratio, making up 64.0, 97.4 and 50.0% in cinnamon bark, cinnamon twig, and shaved cinnamon bark, respectively. The quantities of cinnamyl alcohol, coumarin and cinnamaldehyde also varied between the three parts of the plant. Chemical fingerprints of the three cinnamon samples were established using principal component analysis, the results of which indicate that cinnamon bark and shaved cinnamon bark could be easily differentiated, despite a marked similarity in outward appearance. Cinnamon twig was also shown to depart from the other clusters. The proposed method provides a fast and efficient means of identifying cinnamon herbs for quality control purposes. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
980.
Electroactive shape memory composites were synthesized using polybutadiene epoxy(PBEP) and bisphenol A type cyanate ester(BACE) filled with different contents of carbon black(CB). Dynamic mechanical analysis(DMA), scanning electron microscopy(SEM), electrical performance and electroactive shape memory behavior were systematically investigated. It is found that the volume resistivity decreased due to excellent electrical conductivity of CB, in turn resulting in good electroactive shape memory properties. The content of CB and applied voltage had significant influence on electroactive shape memory effect of developed BACE/PBEP/CB composites. Shape recovery can be observed within a few seconds with the CB content of 5 wt% and voltage of 60 V. Shape recovery time decreased with increasing content of CB and voltage. The infrared thermometer revealed that the temperature rises above the glass transition temperature faster with the increase of voltage and the decrease of resistance. 相似文献