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Exact　Solutions　of　Variation　Problem　on　Shiftability　of　Principal　Shift　Invariant　Spaces

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Wuhan University Journal of Natural Sciences 1997年第1期2卷 11-14页

作者： Wang Qiao department of Mathematics, Wuhan University, Wuhan 4.0072,china Information Science Center, beijing University,beijing 100871,{4. Wuhan University Department of Mathematics Wuhan China (GRID:grid.49470.3e) (ISNI:***) beijing University Information Science Center Beijing China (GRID:grid.11135.37) (ISNI:***)

A complete answer to the shiftability of a principal shift invariant spaces and a scaled version is given. The congruence of spectrum plays a kernel role. It characterizes essentially the shiftability and the scale of any principal shift variant spaces. Some examples relative to signal analysis are discussed associated with an explanation to the failure of generalizing Shannon s sampling theorem from band limitted to band pass case.

关键词： principal shift invariant space shiftability congruence of spectrum

FLUIDIZATION OF CARBON NANOTUBES

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Particuology 2005年第Z1期 40-41+5页

作者： Fei Wei, Cang Huang and Yao Wang department of Chemical Engineering, Tsinghua University, beijing 100084. P. R. china

Carbon nanotubes (CNTs) can be fluidized in the form of fluidlike agglomerates made of many three-dimensional sub-agglomerates, having a multi-stage agglomerate (MSA) structure and containing large amounts of twisting... 详细信息

关键词： carbon nanotubes (CNTs) multi-stage agglomerate (MSA) agglomerate particulate fluidization (APF) inter-particle forces (IPF)

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学生评价教师绩效的结构验证性因素分析

心理学报 2003年第3期35卷 362-369页

作者：蔡永红林崇德陈学锋北京师范大学教育学院北京100875 北京师范大学发展心理研究所北京100875 中国儿童中心北京100035

文章采用开放式调查、关键事件访谈、理论分析等方法建构了教师绩效的结构 ,并通过验证性因素分析验证了学生评价教师绩效的结构包含 6个一阶因子 ,即职业道德、职务奉献、助人合作、教学效能、教学价值与师生互动 ,这 6个因子组成了 2... 详细信息

文章采用开放式调查、关键事件访谈、理论分析等方法建构了教师绩效的结构 ,并通过验证性因素分析验证了学生评价教师绩效的结构包含 6个一阶因子 ,即职业道德、职务奉献、助人合作、教学效能、教学价值与师生互动 ,这 6个因子组成了 2个二阶因子 ,前 3个因子属于关系绩效 ,后

关键词：教师绩效关系绩效任务绩效

A SPECIAL METHOD OF FOURIER SERIES WHICH IS EQUAL TO THE METHOD OF SEPARATION OF VARIABLES ON BOUNDARY VALUE PROBLEM

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Acta Mechanica Solida Sinica 1997年第3期10卷 255-261页

作者： Yan Xianggan Wu Jike, department of Mechanics, Peking Unirersity, Bejing 100871. china beijing UNIV DEPT MECHBEIJING 100871PEOPLES R CHINA

By the separation of singularity, a special Fourier series solution of the boundary value problem for plane is obtained, which can satisfy all boundary conditions and converges rapidly. II is proved that the solution is equal to the result of separation of variables. As a result, the non-linear characteristic equations resulting from the method of separation of variables are transformed into polynomial equations that can provide a foundation for approximate computation and asymptotic analysis.

关键词： separation of singularity series resolution method of separation of variables boundary value problem characteristic equation

Frequency stabilization of Nd:YVO_4.mini-laser using the third-harmonic detection

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Chinese Science Bulletin 2002年第22期47卷 1864-1866页

作者： LIU Yanghui, LI Xiaoyong, Bl Zhiyi & MA Longshengdepartment of Physics, Key Laboratory for Optics and Magnetic Resonance Spectroscopy, East china normal University, Shanghai 200062, china department of Physics Key Laboratory for Optics and Magnetic Resonance Spectroscopy East China Normal University Shanghai China

Via saturated absorption spectroscopy and thethird-harmonic detection techulque, the hyperfine spectra of127I2 near 532 nm have been observed within the tuningrange of a mini Nd: YVO4.KTP laser. The laser is frequencystabilized against one hypeffine structure (hfs) component of127I2. The analysis of error signal shows that it is possible torealize a bouency stability of 3.0 × l0-l3 at 1 s avrmge time.

关键词： Nd:YVO4.KTP laser laser frequency stabilization 3rd-harmonic detection saturated absorption.

Photoinduced intramolecular electron transfer and charge separation in zinc phthalocyanine-viologen linked system

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Chinese Journal of chemistry 1995年第1期13卷 33-39页

作者： SHEN, Shu-Yin LIU, Ji-Xiang ZHOU, Qing-Fu XU, Hui-JunInstitute of Photographic chemistry, Chinese Academy of Sciences,beijing 100101, chinaTakanae, N. Kuriyama, Y. Sakurai, H. Tokumaru, Y. department of chemistry, University of Tsukuba, Ibaraki,305 Japan department of chemistry University of Tsukuba Ibaraki 305 Japan

Photoinduced electron transfer and charge separation processes in zinc phthalocya-nine-viologen linked system have been studied and the distance effect of donor/acceptor on electron transfer reaction is discussed. It is indicated that the fluorescence from the zinc phthalocyanine moiety is appreciably quenched and the life-time of singlet excited state is reduced by the pendant viologen. Time-resolved transient absorption spectra measurements show that intramolecular quenching of the triplet state of zinc phthalocyanine by the attached viologen results in charge separation giving reduced viologen radical alive for a rather long period with hundred microsecond duration. The effect of the carbon chain length on the electron transfer rate constant and charge separation efficiency suggests that upon excitation, the zinc phthalocyanine and viologen groups tend to take closer conformation with the increase of the carbon chain examined. The rate constant for the intramolecular electron transfer ket with n = 3 to 10 is in the order of 104.s-1 and increases.

关键词： Photoinduced electron transfer phthalocyanine viologen.

Different contributions of STAT3, ERK1/2, and PI3-K signaling to cardiomyocyte hypertrophy by cardiotrophin-1

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Acta Pharmacologica Sinica 2004年第9期 55-62页

作者： Ze-jun TIAN, Wei CUI, Yong-jun LI, Yu-ming HAO, Jun DU, Fan LIU, Hui ZHANG, Xiu-guang ZU, Su-yun LIU, Li CHEN, Wei ANdepartment of Cardiology, Second Hospital of Hebei Medical University, Shijiazhuang 050000, china department of Cell Biology and Municipal Laboratory for Liver Protection, beijing 100054. china

AIM: To assess the contribution of signal transducer and activator of transcription 3 (JAK-STAT3) pathway, extracellular signal-regulated kinases1/2 (ERK1/2) pathway, and phosphatidylinositol 3-kinase (PI3-K) pathway to cardiomyocytes hypertrophy induced by cardiotrophin-1 (CT-1), a new member of interleukin-6 (IL-6) family of cytokines. METHODS: STAT3, ERKl/2, and PI3-K were assessed by Western blot analysis. Activity of ERKl/2 was

关键词： cardiac hypertrophy signal transduction cardiotrophin-1 MAP kinase signaling system trans- activators 1-phosphatidylinosito1 3-kinase

希土离子-pmap-吡啶氧化物混配配合物的制备及性质研究

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无机化学学报 1989年第1期5卷 90-92页

作者：陈伯涛任丽萍北京师范大学化学系

合成了Ce(pmap)_4.2H_2O(pmap=1苯基-3 甲基-4.乙酰基-吡唑酮-5);Ln(pmap)_3·2H_2O·xC_2H_5OH(Ln=La-Nd,x=1;Ln=Sm,Eu-Lu,x=0)以及Ln(pmap)_3·L·H_2O(Ln=La-Lu;L=pyno, 3picno,4.icno)等固体配合物,并对它们进行了热谱、电导、红外和可见——紫外光谱等的测试工作。观察到镧系收缩;吡啶氧化物上甲基的取代位置对混配配合物热稳定性的影响;Pr^(3+),Nd^(3+),Ho^(3+),Er^(3+)离子配合物在可见区有超灵敏跃迁现象;从XPS光谱知不同希土离子结合能的对数值与原子序数间有直线关系。

关键词：希土配合物吡啶氧化物镧系元素

Coal-Forming Model in the Context of Non-marine Sequence Stratigraphy:A Case Study of Jurassic Coal Measures in Northern Qaidam Basin,Northwestern china

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地学前缘 2009年第S1期16卷 128-129页

作者： Jing Lu~1,Longyi Shao~1,Taijin Liu~2,Qi Ju~2,Huaijun Wen~2,Hao Wang~1 1.department of Resources and Earth Sciences,china University of Mining and Technology(beijing),beijing 100083,china. 2.Qinghai Administration of Coal Geology,Xining 810000,china

Previous studies of coal sequence stratigraphy have concentrated on coals associated with paralic depositional *** attention has been paid to their counterparts in non-marine intra-mountain coal *** northern Qaidam Basin of northwestern china has been extensively developed with abundant oil and gas as well as coal resources in its Jurassic non-marine successions.A total of six sedimentary systems of the Early and Middle Jurassic

关键词： northern Qaidam Basin Jurassic depositional environment sequence stratigraphy coal accumulation