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Electrical stimulation of cortical neurons promotes oligodendrocyte development and remyelination in the injured spinal cord

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Neural Regeneration Research 2017年第10期12卷 1613-1615页

作者： Dan C.li qun li Department of Neuroscience Emory University School of Medicine Department of Anesthesiology and Critical Care Medicine Johns Hopkins University School of Medicine

Background and early studies： Endogenous tri-potential neural stem cells （NSCs） exist in the adult mammalian central nervous system （CNS）. In the spinal cord, NSCs distribute throughout the entire cord, but exist predominately in white matter tracts. The phenotypic fate of these cells in white matter is glial, largely oligodendrocyte, but not neuronal.

关键词： OPC CNS Electrical stimulation of cortical neurons promotes oligodendrocyte development and remyelination in the injured spinal cord

A Rapid and Convenient Synthesis of Acylals from Aldehydes and Acetic Anhydrides Catalyzed by SnCl_4/SiO_2

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Chinese Chemical letters 2001年第7期12卷 565-568页

作者： Yi qun li li Hui CHENG Department of Chemistry Jinan UniversityGuangzhou 510632

A variety of aldehydes were converted into acylals in excellent yields with acetic anhydride in the presence of a catalytic amount of tin (IV) chloride supported on silica gel at room temperature.

关键词： Acylals tin (IV) chloride supported on silica gel

Cubic hollow porous carbon with defective-edge Fe-N_(4) single-atom sites for high-performance Zn-air batteries

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Journal of Materials Science & Technology 2024年第14期181卷 82-90页

作者： Shilong Zhou Chao Chen Jiawei Xia le li Xingyue Qian Fengxiang Yin Guohong Dai Guangyu He qun Chen Haiqun Chen Key Laboratory of Advanced Catalytic Materials and Technology Advanced Catalysis and Green Manufacturing Collaborative Innovation CenterChangzhou UniversityChangzhou 213164China Department of Chemistry and Chemical Engineering Jiangsu University of TechnologyChangzhou 213001China

Regulating the local coordination of Fe active center can further improve the oxygen reduction reaction(ORR)performance of Fe-N-C catalyst to meet the practical application requirements of zinc-air batteries(ZABs).Herein,carbon vacancies modified hollow porous catalysts(C-FeZ8@PDA-950)are constructed by microenvironment modulation,achieving the efficient utilization of active sites and optimization of elec-tronic *** functional theory(DFT)calculations confirm that the defective-edge Fe-N_(4) sites can weaken the adsorption free energy of OH^(∗),and hinder the dissolution of Fe center,significantly accel-erating the ORR process for *** rechargeable liquid ZABs equipped with C-FeZ8@PDA-950 display high specific capacity(819.95 mAh g Zn^(−1))and excellent long-cycling life(over 500 h).Furthermore,the relevant flexible all-solid-state ZABs also display outstanding folding performance under various bending *** work will provide insights into optimizing the electronic structure to improve electrocatalytic performance in the energy conversion and storage area.

关键词： Hollow porous catalyst ORR Defective-edge Fe-N_(4) sites Zn-air battery DFT calculations

Microstructure and Thermal-protective Property of CPED Coating with ZrO2 Nanoparticles Addition on Al-12Si Alloy

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Journal of Wuhan University of Technology(Materials Science) 2019年第5期34卷 1187-1192页

作者： WANG Ping MA qun li Bin li Yaoyao Shaanxi Key Laboratory of Photoelectric Functional Materials and Devices School of Materials and Chemical Engineering Xi’an Technological University

A novel thermal-protective coating has been successfully prepared by CPED process on a cast Al-12%Si alloy with the addition of ZrO2 nano-particles in the electrolyte. The microstructures and phase composition of the coatings were analyzed by SEM and XRD, and the heat insulation performance and the thermal shock resistance of the coatings were investigated. With ZrO2 nanoparticles addition, the cathode plasma discharge on the coating surface is more obvious than that without ZrO2 nanoparticles addition, the coating is more uniform and compact, and the thickness of the coating increases. Furthermore, the content of Zr and Y elements increases and the degree of crystallization of the coating is more complete. The formation of the solid solution of yttrium stabilized zirconia is promoted by cathode plasma discharge. In addition, the thermal insulation temperature increases as ZrO2 nano-particles are added to the electrolyte. After 1 000 cycles of thermal shock, there was no cracking in the coating surface layer, which indicated that the CPED coating with ZrO2 nanoparticles addition possessed a good thermal shock resistance.

关键词： Al-12Si piston alloy cathode plasma electrolytic deposition(CPED) ZrO2 nanoparticles heat-shielding performance thermal shock performance

Potassium iodide catalyzed reductive dehalogenation ofα-halo-ketones using Hantzsch ester diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate as reductant

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Chinese Chemical letters 2010年第8期21卷 931-934页

作者： Hong Sheng li Yi qun li Department of Chemistry Jinan UniversityGuangzhou 510632China

In the presence of diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate（DHP） and a catalytic amount of potassium iodide,severalα-halo ketones were easily reduced to the corresponding ketones in acetone *** procedure presented here showed several merits such as short reaction time,practical experimental and isolated procedure,and excellent yields of products.

关键词： Dehalogenation α-Halo ketones Hantzsch ester 1 4-Dihydro-2 6-dimethylpyridine-3 5-dicarboxylate Potassium iodide

Structures of sodium vanadate solution under different conditions

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Rare Metals 2018年第1期37卷 59-65页

作者： Ya-li Zhang li-qun Yang Xian-Jin Yu School of Chemical Engineering Shandong University of Technology

Combined with Fourier transform infrared spectroscopy（FTIR） analysis of sodium vanadate solution,the relationship between conductivity and structure was investigated by measuring the electric conductivity of the solution under different alkali concentrations and molar ratios of NaOH to V2O5. Results suggest that the polymerization vanadium acid radical ions gradually transform into monomer with the solution diluting. When the solution is diluted to a certain extent,only the vanadium acid radical ion with V-OH chemical bond exists in the solution. At NaOH concentration of below 105.21 g·L^（-1）,the vanadate anions mainly exist in the form of vanadium acid radical ion with V-OH chemical bond and the ion transference number is approximately from 0.58 to 0.82. In the medium NaOH concentration range of 105.21-117.03 g·L^（-1）, the vanadate anions mostly exist in the form of vanadium acid radical ion with V-OH and V-O-V chemical bonds and the ion transference number is approximately 3.29. At NaOH concentration of above 117.03 g·L^（-1）, vanadate anions exist in the form of vanadium acid radical ion with V-OH and V-O-V chemical bonds.

关键词： Sodium vanadate solution Electric conductivity Migration number Infrared spectroscopy

Selective Reduction of 7-Demethylsinomenine

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Chemical Research in Chinese Universities 2008年第5期24卷 557-560页

作者： li Yu-feng BU Qing-min QIAN Yi PAN Yi li Jian-xin HUANG le-qun ZHU Hong-jun School of Science Nanjing University of Technology Nanjing 210009 P. R. China Department of Chemistry School of Chemistry and Chemical Engineering School of Medicine Nanjing University Nanjing 210093 P. R. China

Several borohydride reagents： sodium borohydride, sodium cyanoborohydride, soudium acetoxyborohydride and soudium triacetoxyborohydride were screened, respectively, for the reduction of 7-demethylsinomenine, which was an α,β-dicarbonyl compound derived from sinomenine. Highly regio-and stereo-selectivity was acquired when sodium cyanoborohydride or NaBH（OAc）3 was used. The product was structurally confirmed as 7R configuration by NMR, X-ray crystal diffraction analysis. Some preliminary discussion was also made on the mechanism of the selective reduction.

关键词： 7-Demethylsinomenine Regioselective reduction Stereoselective reduction Borohydride reagents

CHAOS IN PERTURBED PLANAR NON-HAMILTONIAN INTEGRABle SYSTEMS WITH SLOWLY-VARYINGANGle PARAMETERS

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Applied Mathematics and Mechanics(English Edition) 2001年第11期22卷 1301-1305页

作者： CHEN li-qun(陈立群) Shanghai Institute of Applied Mathematics and Mechanics Shanghai 200072 P R China

The Melnikov method was extended to perturbed planar non-Hamiltonian integrable systems with slowly-varying angle parameters. Based on the analysis of the geometric structure of unperturbed systems, the condition of transversely homoclinic intersection was established. The generalized Melnikov function of the perturbed system was presented by applying the theorem on the differentiability of ordinary differential equation solutions with respect to parameters. Chaos may occur in the system if the generalized Melnikov function has simple zeros.

关键词： Melnikov method perturbed integrable system transversely homoclinic chaos

Electrochemical Behavior of Oxide Films of Stainless Steel in 40 kHz Sonicated Sulphate Electrolytes

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Chinese Journal of Aeronautics 2007年第2期20卷 148-152页

作者： ZHU li-qun li Min-wei WANG Hui School of Materials Science and Engineering Beij＇ing University of Aeronautics and Astronautics Beijing 100083 China Shenyang liming Aero-Engine Group Corporation Shenyang 110043 China

This paper describes effects of 40 kHz ultrasound on the oxide films of stainless steel in sulphate electrolytes so as to determine the transmitted power and to characterize mass transfer and peak current density on the electrode surface. Emphasis was mainly laid on electrochemical oxidations and peeling mechanism of oxide films in sonicated sulphate solutions （0.5 and 1.0 mol/L）. Polarization voltammetry, current response traces and SEM analysis were carded out in order to provide full information as to oxide films surface. Results shows that the rate of electrochemical oxidation, the shape of polarization curves and the surface micrographs in sonicated sulphate electrolytes are different from those obtained without introduction of ultrasound. It is concluded that ultrasound can change the electro-chemical behavior of oxide films by its cavitaion effects, which would produce transient mechanical impulsive force and enhance electrochemical reactions.

关键词： stainless steel oxide films electrolysis ultrasound cavitation