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改性对β沸石表面酸性及丙烯水合醚化反应性能的影响

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燃料化学学报 2002年第4期30卷 353-357页

作者：王国良刘金龙秦如意李树本中国科学院兰州化学物理研究所甘肃兰州730000 中国石化集团公司洛阳石油化工工程公司河南洛阳471003

采用浸渍法和离子交换法 ,制备出一系列改性 β沸石催化剂 ,考察了改性剂对 β沸石表面酸性及丙烯水合醚化反应性能的影响。结果表明 ,硼、锌、铝改性可以提高 β沸石的L酸中心 ,磷、镧、铈改性后 β沸石的B酸中心增加。催化剂的B酸和L... 详细信息

采用浸渍法和离子交换法 ,制备出一系列改性 β沸石催化剂 ,考察了改性剂对 β沸石表面酸性及丙烯水合醚化反应性能的影响。结果表明 ,硼、锌、铝改性可以提高 β沸石的L酸中心 ,磷、镧、铈改性后 β沸石的B酸中心增加。催化剂的B酸和L酸中心与丙烯转化率和异丙醚选择性之间存在着一定的对应关系 :B酸量增加有利于提高丙烯转化率 ,L酸量增加有利于提高异丙醚的选择性。合适的B

关键词：表面酸性改性 β沸石丙烯水合醚化催化性能催化剂异丙醚

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氦在球磨贮氢合金中的存在行为研究

物理学报 2003年第3期52卷 756-760页

作者：刘实郑华赵越熊良钺王隆保杨勋中国科学院金属研究所沈阳110016 中国工程物理研究院绵阳621900

通过正电子寿命测量及结构分析 ,研究了氦气氛球磨LaNi4 .75Al0 .2.5和Zr50 Co50 贮氢合金中氦的存在行为 .研究结果表明 :随着气氛压力增加 ,氦的溶入量增加 ,相对而言 ,LaNi4 .75Al0 .2.5更有利于氦的溶入 ;球磨样品正电子寿命的特征... 详细信息

通过正电子寿命测量及结构分析 ,研究了氦气氛球磨LaNi4 .75Al0 .2.5和Zr50 Co50 贮氢合金中氦的存在行为 .研究结果表明 :随着气氛压力增加 ,氦的溶入量增加 ,相对而言 ,LaNi4 .75Al0 .2.5更有利于氦的溶入 ;球磨样品正电子寿命的特征参数发生变化 ,这表明氦在材料中存在行为的差异 ;对于Zr50 Co50 合金 ,氦首先填充在超细晶粒的三叉晶界或空位团处 ,随着气氛压力增加 ,有小部分氦填入单空位的自由体积处 ,形成空位氦复合体 ;对于LaNi4 .75Al0 .2.5合金 ,氦首先进入单空位大小的自由体积中 ,形成空位氦复合体 .

关键词：球磨存在行为正电子寿命氦引入贮氢合金测量粉末制造

Carbon Nitride Films Deposited on Pt Substrates byMicrowave Plasma chemical Vapor Deposition

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 42-44页

作者： Yongping Zhang Yousong Gu Xiangrong Chang Zhongzhuo Tian Dongxia Shi Xiufang Zhanga Lei Yuan Material Science and engineering School, University of Science and Technology Beijing, Beijing 100083. {2. Beijing Laboratory of Vacuum physics, Institut Material Science and engineering School University of Science and Technology Beijing Beijing 100083 China Beijing Laboratory of Vacuum physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

Carbon nitride thin films have been synthesized on polycrystalline Pt substrates using microwave plasma chemical vapor de- position (MPCVD) technique. The N/C atomic ratio is close to the stoichiometric value 1.3. of C_3._4. The experimental X-ray diffraction spectra contain all the strong peaks of α-C_3._4 and β -C_3._4. The films are a mixture of α-C_3._4 and β -C_3._4. The observed Raman and FT- IR spectra support the existence of C-N covalent bond in carbon nitride compound. The bulk modulus detected by Nano II nanoindentor is up to 3.9 GPa.

关键词： carbon nitride MPCVD, thin film deposition

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超声波电动机技术探讨

微特电机 2004年第4期32卷 37-39,42页

作者：施军丽文贵印黄楠中国工程物理研究院电子工程研究所四川绵阳621900 西南交通大学四川成都610031

文章结合实际,通过理论分析,指出了超声波电动机研制的技术难点和关键因素。就超声波电动机所用功能材料的研发、结构设计和优化、控制技术、试验技术、超声波电动机的制造工艺等进行了详细地阐述。明确了超声波电动机研制的发展方向。

关键词：超声波电动机难点关键因素

Bio-distribution research of a novel 188Re-TPPS4 in mice

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Bio-distribution research of a novel 188Re-TPPS4 in mice

反相高效液相色谱法测定枳实、枳壳中橙皮甙和柚皮甙的含量

首届全国分子核医学暨分子影像学学术交流会

作者： JIA Zhiyun, DENG Houfu, PU Manfey l.Dept. of Nuclear Medicine, West china Hospital. Sichuan University, Sichuan Chengdu 610041, china {2. of Nuclear {3. and Chemistry, china Academy of engineering {3., Sichuan mianyang 62.900

Objective To evaluate biological behaviors of a novel 188Re-TPPS4 porphyrin derivative in normal mice and tumor nude mice. Methods TPPS4 (meso-tetrakis4-sulfophenyl) porphyrin) was synthesized and characterized with improving methods. 188ReO4- was acquired from an 188W/188Re generator. The labelling of TPPS4 with 188ReO4- were optimized and achieved by varying reaction conditions. Neoplasm transplantation model of nude mice bearing melanoma or hepatoma were set up and divided randomly into 2.groups, each contains 5 animals;Normal Kunming mice were randomly divided into 10 groups, 10 animals in each group.188Re-TPPS4 were injected respectively into nude mice and Kunming mice via tail veins , SPECT imaging of the nude mice were carried out at different time and the mice were killed with radioactivity of major organs or tumour determined accordingly. Results It showed that the complexation yield was more than>98% as estimated by paper chromatography in acetone and in saline, with the specific activity up to 16.9GBq (mol.T3.4CPP)-1.188Re-TPPS4 did not significantly decrease during the period of 48h after the derivative formation with the preparation containing lOmg.L-1 Vc (Vitamin C) and via dilution ratio of 188Re-TPPS4 preparation within the range of 5 to 15 using physiological saline. It proved that Vc could increase stability of the derivative in vivo;and 188Re-TPPS4 had biological property of fast blood clearance(-90% 2.h post-injection), certain uptake in kidney and liver, lower activity in other tissues and major renal clearance with its metabolites. At 8h post-injection, the uptake of 188Re-TPPS4 was up to 5.7% and 4.4%(%ID.g-1) in liver tumor and melanoma, respectively;tumour/blood and tumour/muscle ratios in hepatoma-bearing and melanomas-bearing mice were observed to be 3.8、2..0 and 2.6、2..0, respectively. This uptake in the tumour was retained until 2.h post-injection with major activity showing renal clearance, no significant activity was present in other o

关键词： 188Re porphyrin derivative bio-distribution mice tumor-bearing nude mice

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色谱 2002年第6期20卷 585-586页

作者：李秀玲李龙肖红斌梁鑫淼中国科学院大连化学物理研究所辽宁大连116011 大连理工大学化工学院辽宁大连116011

采用高效液相色谱法测定了枳实和枳壳中的橙皮甙和柚皮甙含量。色谱柱为HypersilODS1柱(2.0mm×4 6mmi d ),流动相为乙腈 0 5%乙酸溶液(体积比为2.∶78),流速为1 0mL/min,检测波长为2.3.m。柚皮甙和橙皮甙的线性范围分别为0 060g/L～0 6... 详细信息

采用高效液相色谱法测定了枳实和枳壳中的橙皮甙和柚皮甙含量。色谱柱为HypersilODS1柱(2.0mm×4 6mmi d ),流动相为乙腈 0 5%乙酸溶液(体积比为2.∶78),流速为1 0mL/min,检测波长为2.3.m。柚皮甙和橙皮甙的线性范围分别为0 060g/L～0 604g/L和0 012.g/L～0 12.g/L,柚皮甙和橙皮甙的平均回收率分别为97 1%和95 3.。该方法具有操作简便、分析快速、准确等优点。

关键词：反相高效液相色谱法测定橙波甙柚皮甙枳实枳壳植物药分析

Radar Targets Identification Based on Perfect Parametric Modeling Using Artificial Neural Networks

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Radar Targets Identification Based on Perfect Parametric Mod...

电子与硅烷分子碰撞的散射截面对微晶硅生长影响

2.02.IEEE十区计算机、通信、控制和电机工程会议

作者： WANG Jun institute of Electronic engineering, {2. Academy of engineering physics P.O. Box 919—515,mianyang, Sichuan, 62.900, {2., Fax: 86-816-2.87594, E-mail:

In this paper, we have developed a new targetrecognition procedure. In order to efficiently obtain featurevectors for target discrimination, the closed-formexpression of geometrical wave front have been derived toprovide efficient and accurate computation. The resultingsmall dimensional feature vectors based on the developedextractor are identified using the well-known ANNclassifier. The results show that the presented scheme givessuccessful correct automatic target recognition (ATR) in thelow SNR with low computational costs. Although this workconcentrates mainly on parametric modeling ofelectromagnetic target, further work should study moreefficient ANN architecture when the number of candidatesis dramatically increased in the practice.

关键词： Inverse problem automatic target recognition radar image parametric feature vectors artificial neural networks

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四川大学学报（自然科学版） 2009年第4期46卷 1101-1106页

作者：文书堂姚鹏卢景霄李云居李维强魏长春谷锦华杨仕俄郭学军高哲赵尚丽新乡学院化学与化工学院郑州大学材料物理教育部重点实验室中国原子能科学研究院北京102413 南开大学光电子所

较为系统的研究了甚高频化学气相沉积在高压高功率下生长的微晶硅薄膜.给出了功率密度-气体流量和压强-功率密度的二维相图.用朗缪尔探针测出薄膜沉积时等离子体内部电子温度,并用麦克斯韦-玻尔兹曼分布进行拟合给出电子能量分布函数.... 详细信息

较为系统的研究了甚高频化学气相沉积在高压高功率下生长的微晶硅薄膜.给出了功率密度-气体流量和压强-功率密度的二维相图.用朗缪尔探针测出薄膜沉积时等离子体内部电子温度,并用麦克斯韦-玻尔兹曼分布进行拟合给出电子能量分布函数.由电子能量分布函数出发通过单电子碰撞模型给出等离子体内部各种基浓度的计算公式.并通过数值模拟给出等离子体中 SiH_2.SiH_3.基的浓度.利用 SiH_2. SiH_3.值,结合表面扩散模型,解释气压-功率密度相图中随电子温度的增加(功率的增加),晶化率增大的现象.

关键词：甚高频化学气相沉积微晶硅薄膜散射截面高速生长

The study on application of a mineral additive in lubricating oil for the cylinder liners and gears

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The study on application of a mineral additive in lubricatin...