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Several Remarks on Ball-Coverings of Normed Spaces

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Acta Mathematica Sinica,English Series 2010年第9期26卷 1667-1672页

作者： li xin CHENG zheng Hua LUO Xue Fang liU Wen ZHANG Department of Mathematics Xiamen University Xiamen 361005 P. R. China

This paper presents two counterexamples about ball-coverings of Banach spaces and shows a new characterization of uniformly non-square Banach spaces via ball-coverings.

关键词： Uniformly non-square ball-covering Banach space

Chloride channels are involved in sperm motility and are downregulated in spermatozoa from patients with asthenozoospermia

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Asian Journal of Andrology 2017年第4期19卷 418-424页

作者： Shan-Wen liu Yuan li li-li Zou Yu-Tao Guan Shuang Peng li-xin zheng Shun-Mei Deng lin-Yan Zhu li-Wei Wang li-xin Chen Department of Pharmacology Medical College Jinan University Guangzhou China Department of Pathology and Pathophysiology Medical College Jinan University Guangzhou China Department of Physiology Medical College Jinan University Guangzhou China Male Reproductive Center Family Planning Special Hospital of Guangdong Guangzhou China

Human spermatozoa encounter an osmotic decrease from 330 to 290 mOsm I-z when passing through the female reproductive tract. We aimed to evaluate the role of chloride channels in volume regulation and sperm motility from patients with asthenozoospermia. Spermatozoa were purified using Percoll density gradients. Sperm volume was measured as the forward scatter signal using flow cytometry. Sperm motility was analyzed using computer-aided sperm analysis （CASA）. When transferred from an isotonic solution （330 mOsm I-z） to a hypotonic solution （290 mOsm I-Z）, cell volume was not changed in spermatozoa from normozoospermic men; but increased in those from asthenozoospermic samples. The addition of the chloride channel blockers, 4,4＇-diisothiocyanatostilbene-2,2＇- isulfonic acid （DIDS） or 5-nitro-2-（3-phenylpropylamino） benzoic acid （NPPB） to the hypotonic solution caused the normal spermatozoa to swell but did not increase the volume of those from the asthenozoospermic semen. DIDS and NPPB decreased sperm motility in both sets of semen samples. The inhibitory effect of NPPB on normal sperm motility was much stronger than on spermatozoa from the asthenozoospermic samples. Both sperm types expressed CIC-3 chloride channels, but the expression levels in the asthenozoospermic samples were much lower, especially in the neck and mid-piece areas. Spermatozoa from men with asthenozoospermia demonstrated lower volume regulating capacity, mobility, and CIC-3 expression levels （especially in the neck） than did normal spermatozoa. Thus, chloride channels play important roles in the regulation of sperm volume and motility and are downregulated in cases of asthenozoospermia.

关键词： asthenozoospermia chloride channels CIC-3 sperm motility volume regulation

Effects of Enhanced UV-B Radiation on the Activity and Expression of Alternative Oxidase in Red Kidney Bean Leaves

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Journal of Integrative Plant Biology 2007年第9期49卷 1320-1326页

作者： Ming-Guang Zhao Ying-Gao liu li-xin Zhang lin zheng Yu-Rong Bi Key Laboratory of Add and Grassland Ecology Ministry of Education School of Life Sciences Lanzhou University Lanzhou 730000 China

An increase in ultraviolet （UV） B radiation on the earth＇s surface is a feature of current global climate changes. It has been reported that alternative oxidase （AOX） may have a protective role against oxidative stress induced by environmental stresses, such as UV-B. To better understand the characteristic tolerance of plants to UV-B radiation, the effects of enhanced UV-B radiation on the activity and expression of AOX in red kidney bean （Phaseolus vulgaris） leaves were investigated in the present study. The results show that the total respiration rate and AOX activity in red kidney bean leaves increased significantly during treatment with enhanced UV-B. However, cytochrome oxidase （COX） activity did not change significantly. The H2O2 content was also markedly increased and reached a maximum of 4.45 mmol·L^-1·g^-1 DW （dry weight） at 24 h of UV-B treatment, before dropping rapidly. Both alternative pathway content and alternative pathway activity were increased in the presence of exogenous H2O2. Immunoblotting analysis with anti-AOX monoclonal antibody revealed that expression of the AOX protein increased in red kidney bean leaves under enhanced UV-B radiation, reaching a peak at 72 h. In addition, AOX expression in red kidney bean leaves was induced by exogenous H2O2. These data indicate that the increase in AOX activity in red kidney bean leaves under enhanced UV-B radiation was mainly due to H2O2-induced AOX expression.

关键词： alternative oxidase red kidney bean respiration UV-B radiation

Synthesis and Biological Activity of Novel 2,3-Dihydro-2-phenylsulfonylhydrazono-3-(2′,3′,4′,6′-tetra-O-acetyl-β-D-glucopyranosyl)thiazoles

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Chemical Research in Chinese Universities 2009年第1期25卷 52-55页

作者： WANG Hao-an li Yu-xin li zheng-ming CHENG Hai-ying WANG Su-hua liU Bin Elemento-Organic Chemistry Institute State Key Laboratory of Elemento-Organic Chemistry National Pesticide Engineering Research Center Nankai University Tianjin 300071 P. R. China

A series of novel 2,3-dihydro-2-phenylsulfonylhydrazono-3-（2＇,3＇,4＇,6＇-tetra-O-acetyl-β-D-glucopyranosyl）thiazoles were designed and synthesized via the reaction of thiosemicarbazide with chloroaldehyde. Their chemical structures were characterized by ^1H and ^13C NMR spectroscopy and elemental analysis. The bioassay results indicate that some of these compounds exhibit moderate fungicidal and herbicidal activities.

关键词： Synthesis 2,3-Dihydrothiazole Biological activity

Study on Multiplexing Ability of Identical Fiber Bragg Gratings in a Single Fiber

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Chinese Journal of Aeronautics 2011年第5期24卷 607-612页

作者： liU Jiansheng ZHANG Jing li xin zheng zheng School of Electronics and lnformation Engineering Beihang University Beijing 100191 China

The multiplexing ability of a novel multiplexing fiber Bragg grating （FBG） method based on Optical Time Domain Reflecto meter （OTDR） and Time Division Multiplexing TDM technologies has been theoretically analyzed and studied. This method permits the interrogation of hundreds of identical FBGs with low reflectivity in a single fiber, making the FBG sensors more applicable in the aerospace health monitoring engineering. The analysis shows that the multiplexing ability can be greatly improved if the FBG reflectivity is sufficiently low. And hence, an inexpensive large-scale distributed sensing system based on this method can be realized, When evaluating the multiplexing ability of this system, we propose for the first time that the interference effect of multi-reflections among FBGs should be taken into consideration.

关键词： Bragg gratings multiplexing low reflectivity multi-reflection interference effect

Synthesis of Novel 1-Arylsulfonyl-4-(1′-N-2′, 3′, 4′, 6′-tetra- O-acetyl-β-D-glucopyranosyl)thiosemicarbazides

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Chinese Chemical Letters 2006年第2期17卷 153-155页

作者： Yu xin li zheng Ming li Wei Guang ZHAO Wen li DONG Su Hua WANG State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071

The synthesis of novel 1-arylsulfonyl -4- （1＇-N -2＇, 3＇, 4＇, 6＇-tetra-O-acetyl-β-D-gluco- pyranosyl） thiosemicarbazides via condensation of 2, 3, 4, 6-tetra-O-acetyl-β-D-glucopyranosyl isothiocyanate with substituted phenylsulfonyl hydrazines was described. Their structures and physical properties were confirmed by ^1H NMR, ^13C NMR spectra, elemental analysis and MS.

关键词： Phenylfulfonyl hydrazine thiosemicatbazide condensation.

Structure and mechanical properties of impregnated diamond cutting tools using Cu-based metal matrix

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Structure and mechanical properties of impregnated diamond c...

Numerical simulation and analysis of complex patterns in a two-layer coupled reaction diffusion system

第八届中国功能材料及其应用学术会议

作者： ZHANG Heng-tao XIAO Chang-jiang ZHU ling-yan li zheng-xin Department of Materials Science and Engineering Henan University of Technology

ISBN: (纸本)9783037859698

Cu-based metal matrix,Ti coated and uncoated diamond composite were prepared by hot-press sintering in *** effects of the mixing time and the sintering temperature on the relative density,hardness and transverse rupture strength(TRS) of the matrix were *** of specimens sintered at different temperatures were studied by *** TRS and wear resistant of coated and uncoated diamond segment were *** results show that the optimum mixing time is 20 hours;with the increase of sintering temperature,the relative density,hardness and TRS of the matrix firstly increase and then decrease;the TRS of diamond segment is lower than the matrix sintered at the same temperature and TRS of Ti coated diamond segment increased by6.18%as compared with uncoated diamond segment;moreover the wear resistance of Ti coated diamond segment is better than thatof uncoated diamond segment.

关键词： Cu-based metal matrix Ti coated diamond Structure Mechanical properties

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Chinese Physics B 2015年第4期24卷 491-496页

作者：李新政白占国李燕贺亚峰赵昆 College of Sciences Hebei University of Science and Technology College of Physics Science and Technology Hebei University

The resonance interaction between two modes is investigated using a two-layer coupled Brusselator model. When two different wavelength modes satisfy resonance conditions, new modes will appear, and a variety of superlattice patterns can be obtained in a short wavelength mode subsystem. We find that even though the wavenumbers of two Turing modes are fixed, the parameter changes have influences on wave intensity and pattern selection. When a hexagon pattern occurs in the short wavelength mode layer and a stripe pattern appears in the long wavelength mode layer, the Hopf instability may happen in a nonlinearly coupled model, and twinkling-eye hexagon and travelling hexagon patterns will be obtained. The symmetries of patterns resulting from the coupled modes may be different from those of their parents, such as the cluster hexagon pattern and square pattern. With the increase of perturbation and coupling intensity, the nonlinear system will con- vert between a static pattern and a dynamic pattern when the Turing instability and Hopf instability happen in the nonlinear system. Besides the wavenumber ratio and intensity ratio of the two different wavelength Turing modes, perturbation and coupling intensity play an important role in the pattern formation and selection. According to the simulation results, we find that two modes with different symmetries can also be in the spatial resonance under certain conditions, and complex patterns appear in the two-layer coupled reaction diffusion systems.

关键词： Brusselator model pattern formation Turing mode instability

Study on Energy-saving Technology and Design Optimization of Facade in Cold and Severe Cold Area

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International Journal of Technology Management 2013年第2期 53-55页

作者： Wei li xin zheng Jilin Jianzhu University ChangchunJilin 130118 China

This article take cold regions of nlral residential building envelope as the research object, suitability technical theory as the theoretical basis, we evaluation of rural residential energy envelope because China＇s rural areas is chmacterized by large regional differences and to find a solution for the envelope. It could be considered as the useful reference for retrofit design of similar projects.

关键词： Cold and Severe cold area rural housing envelope energy-saving technologies suitability assessment