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排序方式: 共有409条查询结果,搜索用时 46 毫秒
131.
A. I. Demidov M. S. Kokhatskaya Sun Lyu Bin 《Russian Journal of Applied Chemistry》2005,78(8):1280-1282
The content of sodium carbonate and sodium hydrocarbonate in the active paste of the positive and negative electrodes of a worked-out nickel-iron battery after their prolonged storage in air was determined by means of a conductometric analysis. 相似文献
132.
Synthesis and Modification of Zn‐doped TiO2 Nanoparticles for the Photocatalytic Degradation of Tetracycline 下载免费PDF全文
Shuo Pang Ji‐guo Huang Yun Su Bo Geng Su‐yuan Lei Yu‐ting Huang Cong Lyu Xing‐juan Liu 《Photochemistry and photobiology》2016,92(5):651-657
The synthesis of Zn‐doped TiO2 nanoparticles by solgel method was investigated in this study, as well as its modification by H2O2. The catalyst was characterized by transmission electron microscopy, X‐ray diffraction, Brunauer–Emmett–Teller, UV–visible reflectance spectra and X‐ray photoelectron spectroscopy (XPS). The results indicated that doping Zn into TiO2 nanoparticles could inhibit the transformation from anatase phase to rutile phase. Zn existed as the second valence oxidation state in the Zn‐doped TiO2. Zn‐doped TiO2 that was synthesized by 5% Zn doping at 450°C exhibited the best photocatalytic activity. Then, the H2O2 modification further enhanced the photocatalytic activity. Zn doping and H2O2 modifying narrowed the band gap and efficiently increased the optical absorption in visible region. The optimal degradation rate of tetracycline by Zn‐doped TiO2 and H2O2 modified Zn‐doped TiO2 was 85.27% and 88.14%. Peroxide groups were detected in XPS analysis of H2O2 modified Zn‐doped TiO2, favoring the adsorption of visible light. Furthermore, Zn‐doped TiO2 modified by H2O2 had relatively good reusability, exhibiting a potential practical application for tetracycline's photocatalytic degradation. 相似文献
133.
Xiangyu Lou Jiaxin Lin Chun Yin Kwok Prof. Dr. Hairong Lyu 《Angewandte Chemie (International ed. in English)》2023,62(48):e202312633
The incorporation of two distinct boryl groups at the same carbon center in organic molecules has attracted growing research interest due to its potential for facilitating controlled, precise synthesis through stepwise dual carbon-boron bond transformations. Here we report a method to access u nsymmetrical 1,1- d i b oryl a lkene (UDBA) stereoselectively via the reaction of readily available alkynes with a neutral sp2−sp3 diboron reagent (NHC) B H2- B pin (NHC=N-heterocyclic carbene). Attributing to the chemically easily distinguishable nature of the sp2 and sp3 boryl moieties, controllable stepwise derivatization of the resultant UDBAs is realized. This process leads to various multifunctionalized olefins and organoborons, such as acylboranes, which are difficult to prepare by other methods. 相似文献
134.
Li Jiang Prof. Yanhong Lyu Prof. Aibin Huang Prof. Jianyun Zheng Dr. Chao Xie Prof. Xun Cao Prof. Shuangyin Wang 《Angewandte Chemie (International ed. in English)》2023,62(24):e202304079
Photoelectrochemical lithium (Li) extraction can be expected to provide a useful recycle of Li+ from waste Li-containing battery, but the process is limited by the photocathodes with poor Li+ absorption and low yield rate. Here, we have designed a hierarchical silicon (Si)-based photocathode with mixed-phase tungsten oxide (WO3) cocatalysts for photoelectrochemical Li extraction under 1 sun illumination, achieving a high Li yield rate of ≈223.0 μg cm−2 h−1 and an excellent faradaic efficiency of 91.9 % at 0.0817 V versus Li0/+ redox couple. The WO3 cocatalysts with the mixture of amorphous and crystalline phase accelerates the Li+ insertion and precipitation and enriches the concentration of Li+ at the photocathode surface. This robust photoelectrochemical Li extraction system provides a new insight on designing green and efficient route for cyclic utilization of Li resources in the sustainable energy field. 相似文献
135.
Jian Cheng Ling Chen Xulan Xie Kun Feng Hao Sun Yongze Qin Wei Hua Zhangyi Zheng Ying He Weiyi Pan Wenjun Yang Fenglei Lyu Jun Zhong Zhao Deng Yan Jiao Yang Peng 《Angewandte Chemie (International ed. in English)》2023,62(44):e202312113
Hybrid organic/inorganic composites with the organic phase tailored to modulate local chemical environment at the Cu surface arise as an enchanting category of catalysts for electrocatalytic CO2 reduction reaction (CO2RR). A fundamental understanding on how the organics of different functionality, polarity, and hydrophobicity affect the reaction path is, however, still lacking to guide rational catalyst design. Herein, polypyrrole (PPy) and polyaniline (PANI) manifesting different Brønsted basicity are compared for their regulatory roles on the CO2RR pathways regarding *CO coverage, proton source and interfacial polarity. Concerted efforts from in situ IR, Raman and operando modelling unveil that at the PPy/Cu interface with limited *CO coverage, hydridic *H produced by the Volmer step favors the carbon hydrogenation of *CO to form *CHO through a Tafel process; Whereas at the PANI/Cu interface with concentrated CO2 and high *CO coverage, protonic H+ shuttled through the benzenoid -NH- protonates the oxygen of *CO, yielding *COH for asymmetric coupling with nearby *CO to form *OCCOH under favored energetics. As a result of the tailored chemical environment, the restructured PANI/Cu composite demonstrates a high partial current density of 0.41 A cm−2 at a maximal Faraday efficiency of 67.5 % for ethylene production, ranking among states of the art. 相似文献
136.
Yulin Du Prof. Dr. Yifan Lyu Shiquan Li Dr. Ding Ding Jianghuai Chen Cai Yang Dr. Yang Sun Prof. Dr. Fengli Qu Prof. Dr. Zeyu Xiao Prof. Dr. Jianhui Jiang Prof. Dr. Weihong Tan 《Angewandte Chemie (International ed. in English)》2023,62(10):e202215387
Cell-specific aptamers offer a powerful tool to study membrane receptors at the single-molecule level. Most target receptors of aptamers are highly expressed on the cell surface, but difficult to analyze in situ because of dense distribution and fast velocity. Therefore, we herein propose a random sampling-based analysis strategy termed ligand dilution analysis (LDA) for easily implemented aptamer-based receptor study. Receptor density on the cell surface can be calculated based on a regression model. By using a synergistic ligand dilution design, colocalization and differentiation of aptamer and monoclonal antibody (mAb) binding on a single receptor can be realized. Once this is accomplished, precise binding site and detailed aptamer-receptor binding mode can be further determined using molecular docking and molecular dynamics simulation. The ligand dilution strategy also sets the stage for an aptamer-based dynamics analysis of two- and three-dimensional motion and fluctuation of highly expressed receptors on the live cell membrane. 相似文献
137.
We consider high order finite difference methods for two-dimensional fractional differential equations with temporal Caputo and spatial Riemann-Liouville derivatives in this paper. We propose a scheme and show that it converges with second order in time and fourth order in space. The accuracy of our proposed method can be improved by Richardson extrapolation. Approximate solution is obtained by the generalized minimal residual (GMRES) method. A preconditioner is proposed to improve the efficiency for the implementation of the GMRES method. 相似文献
138.
Lyu Fuyan Qu Yuanyuan Zhang Ningxiao Gao Jie Hao Xuedi Wu Miao 《Journal of Dispersion Science and Technology》2016,37(11):1563-1569
Yield stress is a key rheological parameter of dense paste. Considering practical utility and to estimate the possible slipping flow, yield stress measurements were carried out using the curve extrapolation method and vane method with rheometer in both controlled shear stress (CSS) and controlled shear rate (CSR) model. All measured yield stresses show to increase exponentially with concentration in different scale. The vane method yield stresses are both higher than the extrapolation curve yield stress. For the coal slurry used in this paper, the extrapolation curve yield stress is lower by 17–30% than the dynamic yield stress that obtained under test model CSR. It indicates that wall slip exists in pipeline transportation; meanwhile wall slip can reduce transportation resistance of dense paste to some extent. 相似文献
139.
Tong Luo Chao Wang Xingxiang Ji Guihua Yang Jiachuan Chen Srinivas Janaswamy Gaojin Lyu 《Molecules (Basel, Switzerland)》2021,26(1)
Lignin nanomaterials have wide application prospects in the fields of cosmetics delivery, energy storage, and environmental governance. In this study, we developed a simple and sustainable synthesis approach to produce uniform lignin nanoparticles (LNPs) by dissolving industrial lignin in deep eutectic solvents (DESs) followed by a self-assembling process. LNPs with high yield could be obtained through nanoprecipitation. The LNPs were characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and gel permeation chromatography (GPC). Distinct LNPs could be produced by changing the type of DES, lignin sources, pre-dropping lignin concentration, and the pH of the system. Their diameter is in the range of 20–200 nm and they show excellent dispersibility and superior long-term stability. The method of preparing LNPs from lignin–DES with water as an anti-solvent is simple, rapid, and environmentally friendly. The outcome aids to further the advancement of lignin-based nanotechnology. 相似文献
140.
Dong Lyu Ying-Ying Sun Yu-Qing Lai Glen Thompson Philip Caton-Rose Phil Coates Ying Lu Yong-Feng Men 《高分子科学》2021,39(1):91-101
The isotactic polypropylene(iPP) usually shows a unique parent-daughter lamellae structure in which the parent and daughter lamellae are against each other with a near perpendicular angle(80° or 100°). Inducing a high fraction of oriented cross-hatched structure in iPP during processing is desirable for designing the bi-oriented iPP products. We processed a commercial iPP via tensile-stretching and die-drawing to evaluate the structural evolution of oriented parent-daughter lamellae. It turned out that the die-drawing process had an advantage in attaining a high fraction of oriented cross-hatched structure of iPP, as compared to the free tensile stretching. Besides, the presence of α-nucleating agents affected the formation of oriented parent-daughter lamellae in the die-drawn samples whereas such influence diminished in the free stretched ones. It was found that the confined deformation inside the die led to the well-preserved oriented cross-hatched structure in the die-drawn iPP. 相似文献