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Chemical Research in Chinese Universities 2011年第6期27卷 934-938页

作者： HOU Ju-ying AI Shi-yun College of Chemistry and Material Science Shandong Agricultural University Tai ＇an 271018 P. R. China

A multiwalled carbon nanotubes/poly(bromocresol green) modfied glassy carbon electrode (MWNTs-PBG/GCE) was used to investigate the electrochemical behavior of reduced glutathione(GSH). GSH showed an irreversible oxidation process on MWNTs-PBG/GCE with an oxidation peak at 0.77 V(vs. SCE) in a phosphate buffer solution(pH=4.0). The kinetic parameters of the electrochemical behavior of GSH on MWNTs-PBG/GCE were calculated. Under the optimal conditions and with the help of amperometric method, a linear relationship was obtained between the oxidation peak current and GSH concentration in the range from 2×10-7 mol/L to 5×10-6 mol/L with the detection limit as 1×10-8 mol/L(signal-to-noise ratio of 3). The current reached the steady-state current within about 5 s. The modified electrode surface had very good reproducibility and stability.

关键词： Poly(bromocresol green) Glutathione Electrode Multiwalled carbon nanotube

Study on the breakup lengths of free round liquid jets

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航空动力学报 2007年第8期22卷 1258-1263页

作者： ZHU ying WAN yun-xia HUANG Yong PENG Xin-ke School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100083 China

An experi ment was conducted to measure the breakup lengths of water jets with a high-speed video camera for Weber numbers from0 to about 1.1×*** initial jet diameters are changed from0.3 mmto 1. 0 *** results indicate that at lowjet velocity the breakup lengths of the jets are increased linearly from 0 to a maxi *** the Weber number about 20 the breakup length of the jet reaches its maxi mum value for different initial jet *** based onthe dispersion equationis conducted to study the relationship between the growth rate of the jet surface wave and the maxi mumbreakup *** computations showthat the maxi mumgrowth rate for the axisymmetric surface wave has a turning point at Weber number about 20,and that agrees well with the experi ments.

关键词：高速照相机表面波循环液体喷射分散雾化生长率

Determination of inorganic anions in ethyl acetate by in-line hollow fiber membrane extraction with ion chromatography

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Chinese Chemical Letters 2009年第12期20卷 1498-1501页

作者： Zhen Zhen Hu ying ying Zhong yun Chang Fan Yan Zhu Department of Chemistry Xixi Campus Zhejiang University Hangzhou 310028 China

In this work, a novel hollow fiber membrane extractor was set up to extract inorganic anions from ethyl acetate using deionized water. Inorganic anions in slightly soluble organic solvents can be determined by the in-line hollow fiber membrane extractor coupled with ion chromatography at first time. Different aspects of the extraction procedure such as magnetic stirring speed, extraction flow rate and extraction time were optimized to achieve high extraction efficiency and good separation results. Satisfactory linear range, limits of detection and good repeatability were obtained. The procedure was applied to analyze inorganic anions in two commercial ethyl acetate samples.

关键词： Inorganic anions Ethyl acetate In-line hollow fiber membrane extraction Ion chromatography

Lensing clusters of galaxies in the SDSS-Ⅲ

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Research in Astronomy and Astrophysics 2011年第10期11卷 1185-1198页

作者： Zhong-Lue Wen Jin-Lin Han yun-ying Jiang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

We identify new strong lensing clusters of galaxies from the Sloan Digital Sky Survey Ⅲ （SDSS DR8） by visually inspecting color images of a large sample of clusters of galaxies. We find 68 new clusters showing giant arcs in addition to 30 known lensing systems. Among 68 cases, 13 clusters are ＂almost certain＂ lensing systems with tangential giant arcs, 22 clusters are ＂probable＂ and 31 clusters are ＂pos- sible＂ lensing systems. We also find two exotic systems with blue rings. The giant arcs have angular separations of 2.0jj - 25.7j~ from the bright central galaxies. We note that the rich clusters are more likely to be lensing systems and the separations between the arcs and the central galaxies increase with cluster richness.

关键词： galaxies clusters general -- gravitational lensing

A 27 GHz,simple 2-bit 1×8 phased array

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Journal of Electronic Science and Technology 2024年第3期22卷 26-34页

作者： Jun-Xian Liu yun-ying Man Hao Yang Peng Yang School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

This study demonstrates a simple 2-bit phased array operating at 27 GHz that supports one-dimensional beam scanning with left-handed circular polarization(LHCP).The antenna is constructed using a compact four-layer printed circuit board(PCB)structure,consisting of a 90°phase shifter layer with microstrip structures,a ground(GND)layer,a direct current(DC)control layer,and a circularly polarized annular radiation patch layer with 1-bit phase *** on the proposed unit structure,a 1×8 array with half-wavelength inter-element spacing was designed and *** results show that the array achieves a peak gain of 10.23 dBi and is capable of beam scanning within±50°.

关键词： 27 GHz 2-bit P-i-n diodes Phased array Reconfigurable antennas

Preparation and Characterization of Nano-Se/Silk Fibroin Colloids

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Chemical Research in Chinese Universities 2011年第1期27卷 158-160页

作者： HOU Ju-ying AI Shi-yun SHI Wei-jie College of Chemistry and Material Science Shandong Agricultural University Tai ＇an 271018 P. R. China

A solution-phase approach to the synthesis of nano-Se/silk fibroin colloids（NSeSFC） by reducing selenious acid solution with silk fibroin（SF） was proposed, and the composites were in situ prepared by macrowave method. The nanocomposites were characterized with ultraviolet-visible（UV-Vis） absorption spectrometry, resonance Rayleigh scattering（RRS） spectrometry and transmission electron microscopy（TEM）. The nano-Se（0） solution exhibited the strongest resonance Rayleigh scattering at 579 rim. Through the RRS discussion, we found the best preparation and conservation condition of NSeSFC. The TEM image shows the sizes of the Se（0） particles were about 50 nm and dispersed equably. The resulted NSeSFC exhibited good stability, and it can be kept for a long period.

关键词： Silk fibroin Red selenium nanoparticle Resonance Rayleigh scattering Transmission electron microscopy

Influence of Nucleation Agents Concentration on Crystallization Structure and Properties of Glass-ceramics

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Chinese Journal of Structural Chemistry 2007年第5期26卷 562-566页

作者： WU Ren-Ping YU Yan GU ying yun GUO Jin-Yu School of Materials Science and Engineering Fuzhou University Fuzhou Fujian 350002 China

Deep color glass-ceramics is prepared by using gold tailings as the main raw material, and Cr2O3 is added as nucleation agent. Influence of different Cr2O3 additions on crystallization structure and properties of CaO-MgO-Al2O3-SiO2 glass-ceramics has been discussed so as to select optimum additions. DTA is employed to determine optimum crystallization and nucleation temperatures; XRD and SEM are used to characterize microstructure of each sample; and performance indexes, such as water absorption, bulk density, flexural strength and so on, are also determined. Experimental results show that when 3wt% Cr2O3 is introduced, fine glass-ceramics with diopside as the main crystal and Ca-Fe diopside as the second-crystal is obtained, and its corresponding performance indexes are as follows： water absorption 0.12%, bulk density 2.56 g/cm^3, and flexural strength 70.01 Mpa.

关键词： gold railings glass-ceramics nucleation agent crystallization structure property

Protective Roles of Brassinolide on Rice Seedlings under High Temperature Stress

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Rice science 2008年第1期15卷 63-68页

作者： CAO yun-ying ZHAO Hua College of Life Science Nantong University Nantong 226007 China Key Laboratory of Crop Genetics ＆ Physiology YangzhouUniversity Yangzhou 225009 China

Two indica rice （Oryza sativa L.） materials, Xieqingzao B （sensitive to heat stress） and 082 （tolerant to heat stress） were used to study the role of brassinolide （BR） in protection of rice seedlings from heat stress. Young seedlings were subjected to high temperature （38℃/30℃） and sprayed with 0.005 mg/L of BR. Analysis was conducted on the contents of chlorophyll, protein and malondialdehyde （MDA）, the leakage of electrolyte, the activities of peroxidase （POD） and superoxide dismutase （SOD） and their isozymes expression levels in leaves. Under the high temperature treatment, application of BR significantly increased the contents of chlorophyll and protein, and the activities of POD and SOD, and reduced the content of MDA and the leakage of electrolyte in the leaves of the heat-sensitive material Xieqingzao B, whereas BR had less effect on those of the heat-tolerant material 082 relatively. The BR treatment enhanced the expression of POD isozymes in the leaves of both materials. Under the high temperature stress and BR treatment, the expression of four SOD isozymes reduced in 082, but the expression of two SOD isozymes increased in Xieqingzao B. This suggests that BR plays an important role in protection of rice seedlings from heat stress by enhancing the activities or expression level of protective enzymes in the leaves. The materials with various heat-tolerance might differ in the mechanism of response to heat stress with BR application.

关键词： brassinolide rice seedlings heat stress antioxidase membrane lipid peroxidation

Correlation between social support and depression in elderly stroke patients in the sequelae stage from five communities of Shanghai, China

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Neural Regeneration Research 2011年第19期6卷 1493-1497页

作者： Huiying Zhang Ting Zhou Yaqing Zhang ying Zhang yun Xu Nursing School of Shanghai Jiao Tong University Shanghai 200025 China

Using a convenience sampling method, 81 aged patients who were between 6 and 24 months post-stroke were selected from five communities of Shanghai, China. The correlations between social support and depression, as well as other influential factors, were investigated. Results revealed that 46% （37/81） of the stroke patients suffered from depression. Depression was correlated with social support total scores and the two domains of subjective support and utilization. Older age, male gender, low income, absence of spouse and cerebral hemorrhage were risk factors for depression and identify more vulnerable groups.

关键词： community aged patients stroke depression social support

Microstructure and Mechanical Properties of Hot Rolled Low Silicon TRIP Steel Containing Phosphorus and Vanadium

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Journal of Iron and Steel Research International 2011年第11期18卷 40-45页

作者： HOU Xiao-ying XU yun-bo ZHAO Yan-feng WU Di State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110819 Liaoning China

The microstructure characteristics and mechanical properties of a low-silicon TRIP steel containing phosphorus and vanadium at different finish rolling temperatures were studied by laboratory hot rolling experiments. Dif- ferent ratios of multiphase microstructure （ferrite, granular bainite and retained austenite） are obtained. With a decrease in finish rolling temperature, the volume fractions of ferrite and retained austenite increase. EBSD analysis re veals that most of the ferrite grains are fine, and decreasing of finish rolling temperature leads to an increase in low angle boundaries. Under the joint effects of fine grain strengthening, dislocation strengthening and precipitation strengthening, higher strength is obtained. When the finish rolling temperature is decreased to 800 ℃, the steel has excellent mechanical properties： Rp0.2 =470 MPa; Rm=960 MPa; Rp0. 2/Rm=0. 49; A50 =19.7%; n=0. 25.

关键词： hot rolling low silicons TRIP steel phosphorus vanadium EBSD precipitation