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Enhancement of Selectivity in Capillary Zone Electrophoresis by Adding Ethanolamines or Ethylamines in the Running Buffer

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Chinese Chemical Letters 1997年第11期8卷 985-988页

作者： Yi Yang DONG Ai Jin HUANG Yi Liang SUN(department of Chemistry Peking university Beijing 100871) Beijing Univ Dept Chem Beijing 100871 Peoples R China

Mono-, di-, tri-ethanolamines and di-, tri-ethylamines were used to prepare phosphate buffer at pH 2.5 and shown to be capable of enhancing the separation selectivity of chiral drug pinacidil and melittin in bee venom in capillary zone electrophoresis. The reason is due to the reduction of the average apparent mobilities of the analytes.

关键词： Enhancement of Selectivity in Capillary Zone Electrophoresis by Adding Ethanolamines or Ethylamines in the Running Buffer

A Novel Photoproduct of 2-Methoxycytosine in Phosphate Solution Under Far UV Irradiation

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Chinese Chemical Letters 1999年第8期10卷 623-624页

作者： Feng LIN Jin Long WU Xiao Wei FAN (department of Chemistry, Zhejiang university. Hangzhou 310028) Zhejiang Univ Dept Chem Hangzhou 310028 Peoples R China

Under the irradiation of medium pressure mercury lamp (MPML) the photolysis of 2-methoxycytosine (MAP) in phosphate solution leads to the production of a novel compound C5H8N3O5P. The composition and structure of the ... 详细信息

关键词： UV photolysis 2-methoxycytosine phosphate

Hydrothermal growth of center-hollow star-like ZnO architectures assembled by hexagonal conic nanotubes

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Hydrothermal growth of center-hollow star-like ZnO architect...

Study on near-wall turbulence structures with local Reynolds stress

中国化学会第26届学术年会纳米化学分会场

作者： Hanmei Hu1,*, Chonghai Deng2 , Xianhuai Huang3 1College of Material Science and Engineering, Anhui university of Architecture, Hefei 230022 2 department of Chemistry and Materials Engineering, Hefei university, Hefei 230022, 3department of Environment Engineering, Anhui university of Architecture, Hefei 230022

Three-dimensional （3D） center-hollow star-like ZnO architectures have been successfully fabricated on a large scale using Zn（acac）2 （acac= acetylacetone） and ethylenediamine as starting reactants via a surfactant-assisted hydrothermal technique. Field emission scanning electron microscopy （FESEM） images show that the 3D star-like ZnO architectures are center-hollow, which are composed of hexagonal conic nanotubes. The contrastive experiments results indicate that the introduction of surfactant （PVP or PEG） was indispensable in controlling the growth of star-like ZnO with hollow structure. A possible formation mechanism was proposed. Fig.2. FESEM images of the as-prepared ZnO products: （a,b） using PVP as surfactant and （c,d） Using PEG10000 as surfactant

关键词： Nanostructures Hydrothermal growth ZnO

来源： cnki会议评论

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cnki会议

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Communications in Nonlinear Science and Numerical Simulation 2000年第3期5卷 105-117页

作者： Li LI Chunxiao XU Guixiang CUI and Zhaoshun ZHANG(department of Engineering Mechanics, Tsinghua university, Beijing 100084, China) department of Engineering Mechanics Tsinghua University Beijing 100084 China

The direct- numerical- simulated ch annel turbulence is analyzed with two-dimensional wavelet transform. Considering the relation between turbulence coherent structure and Reynolds stress in near wall region, the local Reynolds stress (LRS) is defined.A new method for extracting coherent signals from turbulence based on the LRS is developed. Velocity fiuctuations are decomposed to coherent signals and background signals. It is found that the scaling exponents of coherent signals have a considerable deviation from the Kolmogorov scaling law q/3 (K41 theory), while that of background signals is very close to q/3. It is confirmed that coherent signals are mainly responsible for the anomalous *** characterized by the positive peaks of LRS, the typical structures in near wall region are obtained by conditional statistical averaging. It is shown that the local character of near-wall turbulence structures can be effectively described with LRS.

关键词： wavelet channel turbulence the local Reynolds stress

Effect of monotoxicity and mixtoxicity of nitroaromatics to the green algae, Scienedesmus obliquus

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Journal of Environmental Sciences 2000年第3期12卷 367-368页

作者： LIU Jing\|ling, LANG Pei\|zheng (department of Environmental Sciences, Northeast Normal university, Changchun 130024, China) 西北师范大学甘肃长春 1 3 0 0 2

In general, many pollutants co\|exist in natural aquatic ecosystems. They affect each other and occur different results, such as synergism, addition and antagonism. So the research at mixtoxicity of contaminants to aquatic organism is more important than monotoxicity. In this paper, 50% effectual inhibition concentration 48h \%EC\%\-\{50\} values of 6 kinds of nitroaromatic compounds to the green algae, \%Scenedesmus obliquus,\% were investigated. Mixtoxic experiments, in which any combination of 2,4\|DNT and other 6 kinds of compounds, indicate: (1) synergisms between 2,4\|DNT and 4\|NAn, as well as 4\|NAnis, 1,4\|DNB; (2) antagonisms between 2,4\|DNT and 4\|NT, as well as 4\|NPh, 4\|NCB.

关键词： monotoxicity mixtoxicity nitroaromatics green algae

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Neural Regeneration Research 2006年第8期1卷 763-765页

作者： Xiaofang Chen1, Yueji Sun2, Haiyan Liu1, Yunqiao Ding1, Shujuan Liu1, Jinghua Chen1, Xueying Wang1, Zhenpeng Han3, Fang Qu3 1department of Neurology, Dalian Port Hospital, Dalian 116015, Liaoning Province, China 2department of Psychology, Dalian Medical university, Dalian 116023, Liaoning Province, China 3 department of Rheumatology, Second Affiliated Hospital of Dalian Medical university, Dalian 116023, Liaoning Province, China 4department of Neurology, Dalian Second People’s Hospital, Dalian 116011, Liaoning Province, China department of Neurology Dalian Port Hospital Dalian 116015 Liaoning Province China department of Psychology Dalian Medical University Dalian 116023 Liaoning Province China department of Rheumatology Hospital of Dalian Medical University Dalian 116023 Liaoning Province China

BACKGROUND: Cognitive impairment after stroke associates with various factors, such as age, educational years, etc. Besides concerning about the recovery of limb function after stroke, we should also focus on the rehabilitation of cognition. Moreover, we’d better pay attention to the control of all the risk factors of stroke, and improve the quality of life in stroke patients. OBJECTIVE: To analyze the factors that affect cognitive impairment after stroke. DESIGN: A related factors analysis. SETTINGS: department of Neurology of Dalian Port Hospital and Dalian Second People’s Hospital. PARTICIPANTS: Totally 148 stroke inpatients were selected from department of Neurology, Dalian Port Hospital and Dalian Second People’s Hospital from April 2004 to December 2005, including 100 males and 48 females, aging 45-75 years with an average age of (67±8) years; Their educational years ranged 2-10 years with an average of (6.1±3.7) years; The disease course ranged 15-30 days; All were right-handed. Inclusive criteria: All were accorded with the diagnostic standard set by the Fourth National Academic Meeting for Cerebrovascular Disease; Confirmed by CT or MRI; Informed consents were obtained from all the subjects. METHODS: After the disease conditions were stable, the patients were assessed with Wechsler memory scale (WMS) and Wisconsin card sorting test (WCST). WMS included forward and backward recitation of numbers and short-term memory (verbal memory, visual recognition). The number of times for correct and wrong classifications in WCST and the time to complete the trail making tests A and B were recorded. The focal volume, area and layer were recorded at 24 hours after admission. The general data of the patients were recorded, including name, sex, age, educational years, history of hypertension, history of diabetes mellitus. Electroencepalograph (EEG) was examined to record the wave shape, blood lipids were detected, and the cognition related indexes were analyzed with the Pe

关键词： Related factors of cognitive impairment after stroke WCST WMS

Electrochemical Characterization of Surface-modified LiMn_2O_4 Cathode Materials for Li-ion Batteries

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Journal of Wuhan university of Technology(Materials Science) 2006年第4期21卷 56-59页

作者：禹筱元 College of Science South China Agricultural University Guangzhou 510642ChinaSchool of Physics & Engineering Sun Yat-sen University Guangzhou 510275China

To improve the performance, the surface of 12Mn2O4 was coated with very fine MgO , Al2O3 and ZnO by solgel method, respectively. The structure and morphology of the coated materials were investigated by X-ray diffraction （ XRD ）, X-ray photoelectron spectroscopy （ XPS ） and scanning electron microscopy （SEM）. The charge and discharge performance of uncoated and surfnce modified 12Mn2O4 spinel at 25℃ and 55 ℃ were tested, using a voltage window of 3.0-4.35 V and a current deasity of 0. 1 C rate. There is a slight decrease in the initial discharge capacity relative to that of uncoated UMn2 O4, bat the cycle ability of 12 12Mn2O4 coated by metal-oxide has remarkably been improved. The EIS measuremeuts of uncoated and Al2O3 -coated 12Mn2O4 were carried out by a model 273 A potentiostatl galvanistat controUed by a computer using M270 software, and using a freqnency response analyzer （ Zsimpwin ） combined with a potentiostate （ PAR 273）. Coaseqnently, the reason for the improved cycle properties is that the surface modification reduces the dissolution of Mn , which results from the suppression of the electrolyte decomposition, and suppresses the formation of passivation film that acts as an electronic insulating layer. In conclusion, the use of surface modification is an effective way to improve the electrochemical performance of 12Mn2O4 cathode material for lithium batteries.

关键词： lithium-ion batteries surface modification metal-oxide coating: 12Mn2O4 cathode

Design of a novel low power 8-transistor 1-bit full adder cell

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Journal of Zhejiang university-Science C(Computers and Electronics) 2011年第7期12卷 604-607页

作者： Yi WEI,Ji-zhong SHEN (department of Information Science and Electronic Engineering,Zhejiang university,Hangzhou 310027,China) department of Information Science and Electronic Engineering Zhejiang University

An addition is a fundamental arithmetic operation which is used extensively in many very large-scale integration (VLSI) systems such as application-specific digital signal processing (DSP) and *** adder determines the overall performance of the circuits in most of those *** this paper we propose a novel 1-bit full adder cell which uses only eight *** this design,three multiplexers and one inverter are applied tominimize the transistor count and reduce power *** power dissipation,propagation delay,and power-delay produced using the new design are analyzed and com-pared with those of other designs using HSPICE *** results show that the proposed adder has both lower power consumption and a lower power-delay product (PDP) *** low power and low transistor count make the novel 8T full adder cell a candidate for power-efficient applications.

关键词： Full adder design Low power CMOS circuit Very large-scale integration (VLSI)

Gas Turbulence Modulation Model for Gas-Solid Flows in Two-Fluid Approach

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Journal of Shanghai Jiaotong university(Science) 2010年第4期15卷 428-433页

作者：曾卓雄潘阳周力行 Aircraft Engineering College Nanchang Hangkong University School of Civil Engineering and Architecture East China Jiaotong University department of Engineering Mechanics Tsinghua University

Turbulence enhancement by particle wake effect is studied by numerical simulation of gas turbulent flows passing over particle under various particle sizes, inlet gas velocities, gas viscosity, gas density and the distance of particles. By performing dimension analysis and using the form of gas-particle interaction source term for reference, a new semi-empirical turbulence enhancement model by the particle-wake effect is proposed. The turbulence model is then incorporated into second-order moment model for simulating gas-particle flows in a horizontal channel with different wall roughness and a sudden-expansion chamber. The results show that this model is with higher calculating accuracy than another two turbulence models in comparison with the experimental results.

关键词： gas-particle flows turbulence modulation particle wake effect