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A COUPLING MODEL OF WATER FLOWS AND GAS FLOWS IN EXHAUSTED GAS BUBBLE ON MISSILE LAUNCHED UNDERWATER

Journal of Hydrodynamics 2007年第4期19卷 403-411页

作者： CHENG Yong-sheng liu hua Department of Engineering Mechanics Shanghai Jiaotong University Shanghai 200030 China

The gas and water flows during an underwater missile launch are numerically studied. For the gas flow, the explicit difference scheme of Non-oscillation and Non-free-parameter Dissipation (NND) is utilized to solve the Euler equations for compressible fluids in the body-fitted coordinates. For the water flow, the Hess-Smith method is employed to solve the Laplace equation for the velocity potential of irrotational water flows based on the potential theory and the boundary element method. The hybrid Eulerian-Lagrangian formulation for the free boundary conditions is used to compute the changes of the free surface of the exhausted gas bubble in time stepping. On the free surface of the exhausted gas bubble, the matched conditions of both the normal velocities and pressures are satisfied. From the numerical simulation, it is found that the exhausted gas bubble grows more rapidly in the axial direction than in the radial direction and the bubble will shrink at its "neck" finally. Numerical results of the movement of the shock wave and the distribution of the Mach number and the gas pressure within the bubble were presented, which reveals that at some time, the gas flow in the Laval nozzle is subsonic and the gas pressure in the nozzle is very high. Influences of various initial missile velocities and chamber total pressures and water depths on both the time interval when the gas flow in the nozzle is subsonic and the peak of the gas pressure at the nozzle end were discussed. It was suggested that a reasonable adjustment of the chamber total pressure can improve the performance of the engine during the underwater launch of missiles.

关键词： exhausted gas bubble Laval nozzle missile launched underwater shock wave gas jet

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New Method for Evaluating Thermal Wear of Rolls in Rolling Process

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Journal of Iron and Steel Research International 2008年第6期15卷 52-55页

作者： LI Chang-sheng liu Xiang-hua WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

A new method was developed by a thermal wear machine to evaluate the thermal wear of roils in steel rolling process. The steel strip and rolls were simulated by upper and lower heating disks. The upper heating disk could he kept at a temperature of over 900 ℃ by induction heating. The pressure between the disks as high as 323.2 MPa could be achieved and the slipping rate could be 12. 7 %. The thermal wear of high speed steel （HSS） roll material, the wear rate of the HSS roll, and the SEM morphology of a worn HSS roll surface were investigated. This method was useful and could be employed to simulate friction and wear between strip and roll during the strip rolling process.

关键词： thermal wear roll friction strip rolling induction heating

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Crystal Structure of Copper(II) Complex with 3 Hydroxyl 1,5 diazacycloheptane N,N diacetate

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Chinese Journal of Structural Chemistry 1999年第1期18卷 40-42页

作者： liu sheng hua FU En Qin CHEN Liao Rong WU Cheng Tai Department of Chemistry Wuhan UniversityWuhan430072 Centre of Analysis and Testing Wuhan UniversityWuhan430072

Crystal structure of copper (II) complex with a new aminocarboxylate ligand, 3 hydroxyl 1, 5 diazacycloheptane N,N  diacetate, C 9H 14 CuN 2O 5·H 2O, M r =311.78 is reported. It crystallizes in orthorhombic Pna2 1 with a=13.340(4), b=8 127(1), c=10.583(4) , V=1147.2(7) 3 , Z=4, D c =1.805g/cm 3, μ =19 287cm -1 (Mo Kα), F (000)=644. The final R and R w are 0.049 and 0.065 for 888 observed reflections with I≥3σ(I ). The result of X ray structure determination shows that the Cu(Ⅱ) forms a planar complex with two oxygen atoms and two nitrogen atoms of the ligand.

关键词： crystal structure aminocarboxylate copper complex

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Shape Setup System for 1700 Hot Strip Mill

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Journal of Iron and Steel Research International 2007年第5期14卷 27-30页

作者： GUO Zhong-feng XU Jian-zhong LI Chang-sheng liu Xiang-hua State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

Shape setup （SSU） system is the core technology for hot strip mill （HSM）. A precise SSU system was used to improve the strip quality for HSM. The function of SSU, setup, and feedback was introduced. The main mathematical models of roll gap profile and longitudinal strain difference are set up. Strip profile allocation strategy was researched according to the SSU system of a domestic 1 700 mm HSM. The SSU system was put into practical use and the measurement results showed that strip flatness variation and strip profile variation could be controlled in target scope.

关键词： SSU hot strip mill, shape strip profile flatness

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含冠醚结构单元螺吡喃化合物的逆光致变色性质及其对碱金属离子的识别作用

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高等学校化学学报 2000年第5期21卷 734-736页

作者：刘盛华吴成泰武汉大学化学系武汉430072

The photochromism and alkali metal cation-induced coloration of indolinospiropyrans possessing monoaza-benzo-15-C-5 at 8-position were investigated by UV-Vis spectrometry. The results indicated that these compounds show negative photochromic properties differed from those of crowned spiropyran derivatives reported, and have an excellent recognition of alkali metal canon.

关键词：冠醚螺吡喃逆光致变色碱金属离子识别作用

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官员治理、外商直接投资与地区环境污染——基于官员激励及其异质性视角

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经济体制改革 2017年第2期 24-30页

作者：刘胜顾乃华暨南大学产业经济研究院

本文运用GMM法,对转型时期由地方官员不同激励动机所引致的生态效应进行了探讨。研究发现:外商直接投资有利于降低地区环境污染,这不仅得益于环境友好型技术及管理经验,更藉由示范溢出、竞争溢出等推动地区产业绿色结构形成;异地交流激... 详细信息

本文运用GMM法,对转型时期由地方官员不同激励动机所引致的生态效应进行了探讨。研究发现:外商直接投资有利于降低地区环境污染,这不仅得益于环境友好型技术及管理经验,更藉由示范溢出、竞争溢出等推动地区产业绿色结构形成;异地交流激化了官员"为增长而竞争"激励,强化了"逐底竞争"行为,抑制了外商直接投资的生态改善作用;官员任期越长,晋升激励越弱,环境保护的积极性降低,削弱了外商直接投资正向的环境效应。

关键词：外商直接投资异地交流官员任期环境污染政府引资行为

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环氧树脂基导热复合材料的制备与性能研究

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化学工程 2022年第7期50卷 22-26页

作者：刘升华 92941部队辽宁葫芦岛125001

为探讨影响导热复合材料性能的关键,以片状六方氮化硼(H-BN)和球形氧化铝(Al_(2)O_(3))为填料,使用三辊开炼机共混制备环氧树脂(EP)基导热绝缘复合材料,选择鳞片石墨为对比实验的填料,制备非绝缘导热复合材料。研究填料种类和质量分数... 详细信息

为探讨影响导热复合材料性能的关键,以片状六方氮化硼(H-BN)和球形氧化铝(Al_(2)O_(3))为填料,使用三辊开炼机共混制备环氧树脂(EP)基导热绝缘复合材料,选择鳞片石墨为对比实验的填料,制备非绝缘导热复合材料。研究填料种类和质量分数对复合材料导热性能、力学性能、介电性能、电阻率和热稳定性等的影响。结果表明:填料的加入能够显著提高复合材料的导热性能,当复配填料总量为120份(以每100 g计)时,H-BN和Al_(2)O_(3)质量比为8∶2时,复合材料的导热系数达0.899 W/(m·K),是纯EP的4.2倍。除对比组外,复合材料均具有较好介电性能、电阻率和热稳定性,是良好的绝缘材料。

关键词：导热性能环氧树脂填充型复合材料

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宁波地区老年学员的微型学习现状与促进策略研究

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成人教育 2016年第10期36卷 12-18页

作者：柳华盛宁波广播电视大学浙江宁波315016

中国已经全面进入老龄社会,如何建设积极老龄化社会是每个人必须面对的问题,要解决老龄问题,其根源并不在老年人,在于新技术的发展应用,在于全社会的努力。正是基于此,研究微型学习在老年群体中的应用情况,试图探索一个适合我国国情的... 详细信息

中国已经全面进入老龄社会,如何建设积极老龄化社会是每个人必须面对的问题,要解决老龄问题,其根源并不在老年人,在于新技术的发展应用,在于全社会的努力。正是基于此,研究微型学习在老年群体中的应用情况,试图探索一个适合我国国情的新的老年人学习模式。研究当前宁波地区老年群体微型学习现状,并对采集的数据进行分析,试图提取影响微型学习的因素,并在此基础上提出了推进微型学习的建议和措施,为推进微型学习在老年教育中的应用提供一个实践路径。

关键词：微型学习老年群体现状促进策略

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Analysis of bromate and bromide in drinking water by ion chromatography-inductively coupled plasma mass spectrometry

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Journal of Groundwater Science and Engineering 2014年第4期2卷 48-53页

作者： HAN Mei JIA Na LI Ke ZHAO Guo-xing liu Bing-bing liu sheng-hua liu Jie Institute of Hydrogeology and Environmental Geology

A method for the detection of bromate and bromide in drinking water by ion chromatography-inductively coupled plasma mass spectrometry(IC-ICP-MS) was developed. The optimized conditions of IC including p H and concentration of the effluent were studied. The results showed that the above two species of bromine were baseline separated within nine minutes under the optimized conditions. The detection limits(S/N=3) of bromate and bromide were 0.23 and 0.12 μg/L, respectively. The RSD(n=6) of the peak areas was 1.2%-3.5%. The method has been successfully applied to the determination of the type bromide in drinking water samples. The recoveries were 95%-109%. The method can be used for the regular analysis of bromate and bromide in real drinking water samples.

关键词： Ion chromatography (IC) Inductively coupled plasma mass spectrometry (ICP-MS) Analysis Bromate Bromide

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2-Aryl-Indenylphosphine Ligands:Design,Synthesis and Application in Pd-Catalyzed Cross-Coupling Reactions

2-Aryl-Indenylphosphine Ligands:Design,Synthesis and Applica...

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中国化学会第十三届全国有机合成化学学术研讨会

作者： Yan Meng-Qi liu Yan liu sheng-hua Yu Guang-Ao Key Laboratory of Pesticide ＆ Chemical Biology Ministry of EducationCollege of ChemistryCentral China Normal University

Pd-catalyzed C-C cross-coupling reactions play a vital role in modern organic *** to the high cost of Pd as well as environmental and product safety issues,the development of highly active Pd catalytic system is crucial to the industrial applications of these coupling *** ligand structure defines the steric and electronic properties of the palladium catalyst and therefore plays a crucial role in the efficiency of the cross-coupling *** aryl substituted indenyl phosphine ligands developed by our group have been widely used in Suzuki-Miyaura,Sonogashira and Buchwald-Hartwig cross-coupling reactions in water.1

关键词： cross-coupling reaction palladium phosphine indenyl

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