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71.
Changchun Ji Guang Yang P. Robert Ilango Junnan Song Deshuang Yu Sujun Han Dongxing Zhang Linlin Li Shengjie Peng 《化学:亚洲杂志》2020,15(13):1957-1962
With the environmental pollution and non‐renewable fossil fuels, it is imperative to develop eco‐friendly, renewable, and highly efficient electrocatalysts for sustainable energy. Herein, a simple electrospinning process used to synthesis Mo2C‐embedded multichannel hollow carbon nanofibers (Mo2C‐MCNFs) and followed by the pyrolysis process. As prepared lotus root‐like nanoarchitecture could offer rich porosity and facilitate the electrolyte infiltration, the Mo2C‐MCNFs delivered favourable catalytic activity for HER and OER. The resultant catalysts exhibit low overpotentials of 114 mV and 320 mV at a current density of 10 mA cm?2 for HER and OER, respectively. Furthermore, using the Mo2C‐MCNFs catalysts as a bifunctional electrode toward overall water splitting, which only needs a small cell voltage of 1.68 V to afford a current density of 10 mA cm?2 in the home‐made alkaline electrolyzer. This interesting work presents a simple and effective strategy to further fabricating tunable nanostructures for energy‐related applications. 相似文献
72.
Nonlinear Dynamics - This paper studied the problem of stability and stabilization for a coupling permanent magnet synchronous motors (CPMSMs) system with input delay. Input delays caused by... 相似文献
73.
本文研究了用ICP-AES法,不必化学分离,一次同时测定混合稀土铜合金名14种稀土和非稀土元素,获得满意结果。 相似文献
74.
75.
共价氢化物与汞离子反应的研究:Ⅱ.痕量硒的高灵敏分析新方法 总被引:4,自引:0,他引:4
本文详细研究了硒化氢与汞离子反应条件并建立了氢化物发生-冷原子荧光法间接测定痕量硒的新方法。考察了各种实验条件,并将此方法用于合成水样分析,得到一些有意义的结果。 相似文献
76.
Systematic study of the photoluminescence dependence of thiol-capped CdTe nanocrystals on the reaction conditions 总被引:1,自引:0,他引:1
A modified method to prepare high-quality thiol-capped CdTe nanocrystals (NCs) was reported in this paper. The experimental results showed that the different molar ratios of the ligands (thioglycolic acid) to monomers (Cd2+ ions) in the precursor solution played an important role in the photoluminescence (PL) quantum yield (QY) of the as-prepared CdTe NCs. When [ligand]/[monomer] = 1.2, the maximum fluorescent emission peak appeared in the orange-red window, and the PL QY increased up to 50% at room temperature without any postpreparative treatment. In the meantime, suitable reaction conditions were in favor of the optimization of the surface structure of NCs, resulting in the relatively high PL QY from green to red. In addition, some differences between hydrothermal synthesis and traditional aqueous synthesis of CdTe NCs were discussed. 相似文献
77.
WANG Chun-yan ZHANG Yu-jing College of Animal Science Veterinary Medicine Jilin University Changchun P. R. China 《高等学校化学研究》2011,(2)
The lack of efficient and non-toxic gene delivery, preferably with non-viral DNA vectors, is generally regarded as a major limitation for gene therapy. In this study, a wheat histone H4 gene was cloned from Triticum aestivum, sequenced, modified and expressed in E. coli. The wheat histone H4 gene and reconstructed H4TL gene encoded wheat histone H4 and a recombinant protein of 141 amino acids with an approximate molecular weight of 15500. Gel electrophoresis mobility shift assays demonstrated that the purif... 相似文献
78.
GUO Jin-shan LI Jian-zheng JING Xia-bin CHEN Xue-si HUANG Yu-bin . State Key Laboratory of Polymer Physics Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun P. R. China . Graduate School of Chinese Academy of Sciences Beijing 《高等学校化学研究》2011,(2):329-333
A new kind of biodegradable pH-sensitive drug delivery system was developed via chitosan-albumin conjugate hydrogel. Through changing the feeding modes of reactants, two types of hydrogels(comb-type and reticular-type) were synthesized by amidation reactions between 6-O-succinoylated N-phthaloyl chitosan and albumin. The structures and morphologies of the hydrogels were characterized by SEM. And their water swelling capacity, drug loading and releasing properties at different pH values were also investigate... 相似文献
79.
HAN Tian-jiao WANG Qing SONG Feng-rui LIU Zhong-ying LIU Zhi-qiang LIU Shu-ying . Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Center of Mass Spectrometry Changchun P. R. China 《高等学校化学研究》2011,(3):380-384
In vitro models of human colon carcinoma cell line(Caco-2 cell monolayer) and human intestinal bacteria were used to investigate the intestinal transport and biotransformation of resibufogenin and cinobufagin in Chan Su by HPLC/APCI-MSn. The experimental results of Caco-2 cell monolayer demonstrate that the apparent permeability coefficients(Papp) of resibufogenin and cinobufagin are higher than 10-6 cm/s, which indicates that both resibufogenin and cinobufagin have a good absorption in the small intestine.... 相似文献
80.
An asymmetric metamaterial exhibiting an analog of double electromagnetically induced transparency(EIT) in the middle-infrared region is reported.The metamaterial consists of two-layered arrays of Ushaped rings embedded in a medium,with the lower layer rotated by 90°.Our simulations demonstrate that both maximum group indexes are extremely high at the two EIT-like positions.The group index reaches about thrice the currently reported maximum value at the high-frequency EIT-like position.The transmittance at the two transparency positions also possesses extremely high Q factors,which is conducive to controlling the propagation of electromagnetic waves. 相似文献