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Structural and Electrical Properties of Cobalt Ferrite

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Journal of Materials Science & Technology 1996年第6期12卷 417-420页

作者： C.O.Augustin l.K.Srnivasan P.Kamaraj and A.Mani (Central Electrochemical Research Institute, Karaikudi-630006, India)(To whom correspondence should be addressed) Central Electrochemical Research Institute Karaikudi-630006 India

Ferrites are a class of cohesive new materiafs required for many specialised applications. Cobalt ferrite (CoFe2O4) has been identified as a substitute for carbon and serves as a non consumable anode for an eco-friendly and energy efficient production of aluminium. Pellets of cobalt ferrite have been prepared by powder metallurgical process and their electrical properties have been investigated from ambient temperature to 1273 K. The structural and morphological features have been studied by X-ray diffraction and scanning electron microscopy The relationships between such properties, chemical composition and sintering temperatures are thoroughly discussed.

关键词： nm Structural and Electrical Properties of Cobalt Ferrite

Different patterns of agonist-induced modulation of α_(1B)-adrenoceptor density at different initial expression levels

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Chinese Science Bulletin 2000年第17期45卷 1575-1578页

作者： lEI Beilei & HAN QideInstitute of Vascular Medicine, The Third Hospital, Beijing Medical University, Beijing 100083, China correspondence should be addressed to Han Qide Institute of Vascular Medicine The Third Hospital Beijing Medical University Beijing China

We compared the norepinephrine (NE) induced α1B-adrenoceptor (α1B-AR) expression modulation between two transfected human embryonic kidney (HEK) 293 cell lines in which α1B-AR densities were (6 336 ±913) and (773±164) fmol · mg -1, respectively. Treatment of cells with NE (10 μmol · l1) for 48 h decreased high-level expressed α1B-AR density, but increased low-level expressed α1B-AR density. The protein kinase C inhibitor Calphostin C or Ro-31-8220 reversed, and its activator PMA mimicked the NE-induced down-regulation of high-level expressed α1B-AR. Moreover, PMA induced a down-regulation of low-level expressed α1B-AR. The endoplasmic reticulum Ca2+-ATPase inhibitor cyclopiazonic acid (CPA) and the calcium chelator BAPTA/AM did not affect the down-regulation of high-level expressed α1B-AR, but inhibited the up-regulation of low-level expression α1B-AR induced by NE. These results suggest that α1B-adrenoceptor densities at different initial expression levels are differentially regulated

关键词： α1B-adrenoceptor human embryonic kidney cells regulation signal transduction.

A Neutral Carrier Based Phosphate Sensor with Anti-Hofmeister Behavior

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Chinese Chemical letters 1997年第3期8卷 251-254页

作者： Dong lIU Wen Can CHEN Rong Hua YANG Ru Qin YU （Department of Chemistry & Chemical Engineering, Hunan University, Changsha 410082 ）（ to whom correspondence should be addressed ） Department of Chemistry Hunan University Changsha 410082 China

A PVC membrane electrode, using bis(tribenzyltin) oxide as the carrier, displayed selective response to hydrogen phosphate in the 5x10(-6) mol/l to 10(-1) mol/l activity range with a slope of -30.1mV/dec. in solutions of pH7.2. The comparison of potential response characteristics between the binuclear and mononuclear organotin compounds has been made, showing that binuclear organometallic compounds may become a promising class of carriers for anions.

关键词： Cl HP

EPR Study of Borax-glasses with Addition of Fe^(3+) Ions

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Journal of Materials Science & Technology 1994年第2期10卷 97-106页

作者： M.Peteanu l. Cociu and I. Ardelean (Dept. of Physics, University of Cluj-Napoca, Str. M.Kogalniceanu No. 1, 3400 Cluj-Napoca, Romania)(To whom correspondence should be addressed) Univ of Cluj-Napoca Cluj-Napoca Romania

Glasses of xFe2O3 (l-x) Na2B4O7 for 0.3≤x≤5 mol% have been studied by means of EPR. The distribution of Fe3+ ions in the vitreous network. as isolated and connected in clusters. depends on the impurity contents in the glass. A thermal treatment inducing the Fe3+ -rich phase separation ends at the sample crystallization, when performed at about 550℃, Weathering of glasses causes a Superficial alteration of their optical properties. It enters the bulk of the glass for powdered samples. As a result of gamma irradiation pararnagnetic hole centers were detected:the BOHC. the peroxy radical and the iron hole centers

关键词： Fe Ions EPR Study of Borax-glasses with Addition of Fe

Determination of Trace Silver( Ⅰ ) in Basic Aqueous Solution by Electrochemiluminescence of a New Reagent 6-(2-Hydroxy-4-Diethylaminophenylazo)-2,3-Dihydro-1,4-Phthalazine-1,4-Dione

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Chemical Research in Chinese Universities 1991年第1期7卷 32-36页

作者： An Jingru lin Jinming (Department of Chemistry, Fuzhou University, Fuzhou) To whom correspondence should be addressed.

The electrochemiluminescence (ECl) of a new reagent 6- (2-hydroxy- 4 diethy laminophenylazo)-2,3-dihydro-1 ,4-phthalazine-1,4-dione (HDEA) in a basic aqueous so lution was studied by using the apparatus designed by ourselves. Trace amounts of silver ( Ⅰ ) shows a significant effect on the efficiency of light emission of HDEA during a positive trigonometrical wave pulse was exerted on the solution. The linear relationship between the light intensity and the concentration of silver( Ⅰ ) occurs in the range of 5. 0×10-8 to 3. 0×10-8 mol/l Ag(Ⅰ ) in a medium of KOH-KCl-HDEA (pH= 12. 8). The detection limit of the method is 2. 0×10-8 mol/lAg( Ⅰ ), and the r. s. d. for 1.0×10-7 mo)/l Ag ( Ⅰ ) is 5%. Of 21 metal ions concerned, only nickel( Ⅱ ), cerium( Ⅳ ) and cobalt( Ⅱ ) interfere the silver detection seriously; Ⅰ and Br also have some interference.

关键词： Electrochemiluminescence Reagent Silver 6 ( 2 Hydroxy-4 diethy laminophenylazo)-2,3-dihydro-1 4-phthalazine 1 ,4-dione

Periodicity and map for discovery of new ionic liquids

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Science China Chemistry 2006年第2期49卷 103-115页

作者： ZHANG Suojiang, SUN Ning, ZHANG Xiangping & lü Xingmei Research laboratory for Green Chemical Engineering and Technology, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100080, China correspondence should be addressed to Zhang Suojiang Research laboratory for Green Chemical Engineering and Technology Institute of Process Engineering Chinese Academy of Sciences Beijing China

There is virtually no limit in the number of ionic liquids. How to select proper ones or discover new ones with desirable properties in such a large pool of ionic liquids? It has become a bottleneck in the researches and applications of ionic liquids. Mendeleev’s periodic law states that the properties of the elements vary periodically. Whether the similar regularity exists among ionic or mo-lecular fragments of compounds is an interesting topic. In this work, we attempted to establish a pe-riodicity and draw a “map” of ionic liquids for providing definite guidance to discover, design, and se-lect the proper ionic liquids rather than trial-and-error. If a complete regularity of the system of ionic liquids can be finally established in the future, we are near an epoch in understanding the existing differences and the reasons for the similarity of the ions or molecular fragments.

关键词： ionic liquids molecular fragment periodicity map

Aligning DNA on Si surface and cutting off by tips of atomic force microscope

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Chinese Science Bulletin 2003年第8期48卷 800-803页

作者： lI Hui & HAN Baoshan Institute of Physics, State Key laboratory of Magnetism, ChineseAcademy of Sciences, Beijing 100080, China correspondence should be addressed to Han Baoshan (e-mail: bhan@*** Institute of Physics State Key Laboratory of Magnetism Chinese Academy of Sciences China

DNA is a kind of promising molecule as nano-lead to build or connect nano-devices due to its stable linear structure and certain conductivity. Many methods have been applied to constructing nano-patterns by using DNA molecule. In this report it is presented that l-DNA was aligned on Si substrate by using the free-flowing method and then imaged by an atomic force microscope (AFM). After the second liquid flow, a catenary-like pattern and a crossed network of l-DNA were formed. In addition, the alignedl-DNA was successfully cut off by tips of AFM.

关键词： Si 硅原子显微镜 AFM DNA 脱氧核糖核酸

Relationship between differ- ential gene expression pat- terns in functional leaves of maize (Zea mays l.) at milk filling stage and heterosis using cDNA-AFlP

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Chinese Science Bulletin 2003年第1期48卷 76-81页

作者： TIAN Zengyuan & DAI Jingrui National Maize Improvement Center of China, China Agricultural Uni-versity, Beijing 100094, China correspondence should be addressed to Tian Zengyuan (e-mail: tian-zengyuan@***) National Maize Improvement Center of China China Agricultural University Beijing 100094 China

To understand the molecular mechanism of maize heterosis, differential gene expression patterns in the functional leaves of 35 maize hybrids relative to their parents involving 10 elite inbreds at milk filling stage were analyzed by using cDNA-AFlP. The correlation analyses of various differential expression patterns with the performance and heterosis of main maize agronomic traits were evaluated. The main results were as follows: For uniparental specific expression, significant positive correlations were detected with the performance of seed weight per ear and 100-seed weight at 0.01 and 0.05 probability levels respectively. For biparental specific expression, significant negative correla-tions were detected with the performance of ear diameter and seed weight per ear at 0.01 probability level. For uni-parental specific expression, significant positive correlations were detected with the heterosis of ear diameter and seed weight per ear at 0.01 and 0.05 probability levels respectively. For biparental specific expression, significant negative cor-relation was detected with the heterosis of ear diameter at 0.05 probability level. However, for F1-specific expression, for fragments detected only in one parent and F1, and for fragments detected only in two parents or only in F1, no sig-nificant correlation was detected with the performance or heterosis of all agronomic traits surveyed.

关键词：玉米灌浆期叶片差异基因表达模式杂种优势相关性 cDNA-AFlP 农艺性状

A new method for studying caffeine's antioxygenic property: Peroxidase-Oxidase biochemical reaction

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Science Bulletin 2003年第16期48卷 1728-1732页

作者： WANG Jun, CAI Ruxiu, lIN Zhixin & lIU Zhihong Department of Chemistry, Wuhan University, Wuhan 430072, China correspondence should be addressed to Cai Ruxiu (e-mail: dlxfxc@ ***) Department of Chemistry Wuhan University Wuhan 430072 China

The effect of Caffeine on Peroxidase-Oxidase (PO) reaction was studied systematically in this paper. We proved that the valley of PO oscillation is the best phase an-gle which was used to research antioxygenic property by the Analyte Pulse Perturbation Technique (APP), based on in-vestigating the mechanism. Area integral calculus was pro-posed to use in quantitative analysis for the first time. There is a good linear relationship (R = 0.9950) between the ratio of amplitude changes of PO oscillation and the concentration of caffeine in the range 4.61×10-7 mol/l—1.84×10-5 mol/l. A new method for analysis by PO oscillation was set up. We also investigated two-dimensional projections and Fourier spectrum of nonlinear complicate system——PO reaction which was perturbed by caffeine, in order to provide a theo-retical basis for studying effects of kinds of antioxidants on life system.

关键词： PO reaction HRP caffeine oscillation.