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Rose solutions with three petals for planar 4-body problems

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Science china Mathematics 2010年第12期53卷 3085-3094页

作者： DENG ChunHua 1,2., ZHANG ShiQing 1, & ZHOU Qing 3 1 Yangtze Center of Mathematics and college of Mathematics, Sichuan University, Chengdu 610064, china 2.Faculty of Mathematics and Physics, Huaiyin Institute of {2., Huai’an 2.3001, china 3 department of Mathematics, East china Normal University, Shanghai 2.0062. china 1. Yangtze Center of Mathematics and college of Mathematics Sichuan University Chengdu 610064 China2. Faculty of Mathematics and Physics Huaiyin Institute of Technology Huai’an 223001 China3. Department of Mathematics East China Normal University Shanghai 200062 China

For planar Newtonian 4-body problems with equal masses, we use variational methods to prove the existence of a non-collision periodic choreography solution such that all bodies move on a rose-type curve with three pet... 详细信息

关键词： 4-body problems with Newtonian potentials rose solutions with three petals winding numbers variational minimization methods

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二阶可降阶微分约束系统的形式不变性

物理学报 2003年第9期52卷 2105-2108页

作者：葛伟宽张毅湖州师范学院物理系湖州313000 苏州科技学院土木工程系苏州215011

研究具有二阶可降阶微分约束的力学系统的形式不变性 .采用两种方法 :一是用不可降阶微分约束系统的方法 ;另一是用降阶后系统的方法 .研究两种方法之间的关系 .结果表明。

关键词：力学系统形式不变性守恒量二阶可降阶微分约束系统运动微分方程二阶非完整系统

Solving and Applying a Class of Block-diagonal Structured Large Linear Programming

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Systems Science and Systems Engineering 1998年第2期8卷 93-99页

作者： SHENG Jie department of Mathematics, teachers {2., Yangzhou University CHENG Jieling Departemt of Irrigation, Agriculture {2., Yangzhou University CHEN Yixin department of Computer Science, University of Science and technology of china

Using large block diagonal structured linear problem as illustration, we present the "gradient simplex" method for solving large linear *** solving some large block diagonal structured linear problem with fewer coupling constrants, this method is much faster then the simplex method, and can surmount the capacity and speed restrictions of computer to certain *** this paper, we discuss the efficiency and applicability of the method and analysis its performance in the examples of economic development optimize programming model.

关键词： linear programming method

Phylogeny of Ptychostomum (Bryaceae,Musci) inferred from sequences of nuclear ribosomal DNA internal transcribed spacer (ITS) and chloroplast rps4

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Journal of Systematics and Evolution 2009年第4期47卷 311-320页

作者： ~(1,2.Chen-Ying WANG ~1Jian-Cheng ZHAO~* 1(college of Life Science,Hebei Normal University,Shijiazhuang 050016,china) 2.{2. of Life Science,Zhengzhou teachers college,Zhengzhou 450044,china) ( department of Life Science Zhengzhou Teachers College Zhengzhou 450044 China)

The phylogeny of Ptychostomum was first undertaken based on analysis of the internal transcribed spacer(ITS)region of the nuclear ribosomal(nr)DNA and by combining data from nrDNA ITS and chloroplast DNA rps4 *** parsimony,maximum likelihood,and Bayesian analyses all support the conclusion that the reinstated genus Ptychostomum is not *** funkii(Schw(a|¨)gr.)*** (≡Bryum funkii Schw(a|¨)gr.)is placed within a clade containing the type species of Bryum,*** Hedw. The remaining members of Ptychostomum investigated in the present study constitute another well-supported clade. The results are congruent with previous molecular *** the basis of phylogenetic evidence,we agree with transferring *** Mü***.(≡***(Brid.)Turton≡Bryum archangelicum Bruch & Schimp.), Bryum lonchocaulon Mü***.,Bryum pallescens *** Schw(a|¨)gr.,and Bryum pallens *** Ptychostomum.

关键词： Bryum molecular phylogeny nuclear ribosomal DNA internal transcribed spacer sequences Ptychostomum rps4 sequences.

The Thermal Resistance and Its Measurement of a Modular Micro-channel Cooler

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Chinese Journal of Lasers 2000年第4期9卷 43-49页

作者： DAI Teli (department of Physics and Information technology of Chongqing {2. college, Chongqing 400047, china) 重庆师范学院重庆

The thermal impedance of Modular Micro channel Cooler (MCC) is the summation of the thermal impedances from heat source to silicon substrate, the silicon walls (fins), the interface between the PN junction bottom and indium layer, and the boundary layer of the coolant. The equations about the thermal conduction of MCC have been established and solved. The measurement of the thermal impedance of the MCC gave three curves that are the temperature rise versus the thermal power dissipated, the water flow versus the pressure across the device, and the wavelength versus the inverse water pressure. The calculated value of the thermal impedance from solving equations is in agreement with the measured value of the thermal impedance from the three curves.

关键词： modular micro cooler theranal impedance diode laser

Investigation on the 773 K isothermal section of La-Fe-Sn ternary systems by X-ray powder diffraction

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Rare Metals 2010年第6期29卷 567-571页

作者： CHEN Xiang ZHUANG Yinghong CHEN Yungui Key Laboratory of Nonferrous Metal and New Processing technology of Materials (Ministry of Education of china) Guangxi University Nanning 530004 China department of Physics and Electronic Information Engineering Neijiang Teachers College Neijiang 641002 China department of Metallic Materials Engineering Sichuan University Chengdu 610065 China

The 773 K isothermal section of the La-Fe-Sn ternary system was investigated and constructed by X-ray powder diffraction（XRD）.The existence of two reported ternary intermetallic compounds,La6Fe13Sn and La3FeSn6,is confirmed in this *** with other R-Fe-Sn phase diagrams（R = Pr and Sm）,the binary alloys Fe3Sn and Fe5Sn3 are not *** compound Fe3Sn2.was observed from the XRD pattern of Fe3Sn2.samples,but it is not an equilibrium phase at 773 K and decomposes into Fe and FeSn phases completely for a longer heat treated *** to now,the crystal structure data of La2.n3 has not been reported,so the X-ray pattern of La2.n3 was only *** phase relationship for this compound was drawn by a dotted line.

关键词： intermetallics quenching phase diagrams X-ray diffraction.

Adsorptive desulfurization on a heteroatoms Y zeolite prepared by secondary synthesis

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Science china Chemistry 2010年第1期53卷 281-286页

作者： TANG Ke1,HONG Xin1,ZHAO YongHua1,SONG LiJuan2.& SUN ZhaoLin2.1School of Material and Chemical Engineering,Liaoning Institute of technology,Jinzhou 12.001,china 2.2. of Petrochemical Engineering,Liaoning University of Petroleum & Chemical technology,Fushun 113001,china 1. School of Material and Chemical Engineering Liaoning Institute of Technology Jinzhou 121001 China2. College of Petrochemical Engineering Liaoning University of Petroleum & Chemical Technology Fushun 113001 China

Gallium atoms have been introduced into the framework of Y zeolite by treating the zeolite with an aqueous solution of ammonium hexafluoro *** of various model fuels containing about 500 μg/g sulfur has been studied over the synthesized Y zeolite(GaAlY).The sulfur adsorption capacity is 7.0,17.4,14.5,16.9,6.9 and 5.8 mg(S)/g adsorbent for thiophene,tetrahydrothiophene(THT),4,6-dimethyldibenzothiophene(4,6-DMDBT),dibenzophiophene(DBT),benzothiophene(BT) and 4-methyldibenzothiophene(4-MDBT),*** charges on the S atom in thiophene,THT,4,6DMDBT,DBT,BT and 4-MDBT,calculated using the density functional theory(DFT),are-0.159,-0.2.8,-0.2.4,-0.2.1,-0.193 and-0.188,respectively,implying that the S-M bond between the adsorption sites and thiophene is much weaker than that between the adsorption sites and THT,4,6-DMDBT or *** sulfur removal of FCC gasoline on GaAlY is 68%.

关键词： isomorphous substitution DFT model fuels adsorptive desulfurization

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日本初中地理科目的改革

外国教育研究 2001年第6期28卷 35-38页

作者：兰婷四平师范学院教育系吉林四平136000

本文依据日本 1 998年 1 2.颁布的新学习指导要领 ,对日本初中地理科目的教育目标、教育内容等方面的改革进行了介绍、评析 ,并指出这次地理科目课程改革的特点。

关键词：日本初中地理科目课程改革教育目标教育内容

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英国职业教育与学习型社会

外国教育研究 2005年第4期32卷 77-80页

作者：黄日强张霞江西科技师范学院职业教育研究所江西南昌330013 东华理工学院教育心理学部江西抚州344000

学习型社会是终身学习、全民学习、开放学习、多样化学习的社会。在这种社会中,职业知识和技能是学习的主要内容,职业教育较之传统社会在教育对象、教育时间和场所、教育形式方面都有了巨大的变化。因应这种时代潮流,英国职业教育作为... 详细信息

学习型社会是终身学习、全民学习、开放学习、多样化学习的社会。在这种社会中,职业知识和技能是学习的主要内容,职业教育较之传统社会在教育对象、教育时间和场所、教育形式方面都有了巨大的变化。因应这种时代潮流,英国职业教育作为学习型社会终身教育的大平台,在推广终身学习理念和实践终身学习理想方面做了一系列有益的尝试。

关键词：英国学习型社会职业教育终身教育