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Preparation and characterization of bis(dimolybdo-nonatungstogermanate)lanthanates of potassium

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Rare Metals 2003年第1期22卷 6-9页

作者： WU Qingyindepartment of chemistry, Zhejiang university, Hangzhou 3.0027,{3. department of chemistry Zhejiang University Hangzhou 310027

The heteropoly complexes K_(13.[Ln(GeW_9Mo_2O_(3.))_2] centre dot nH_2O (Ln =La, Ce, Pr, Nd, and Sm) were prepared for the first time and characterized by chemical analysis,infrared (IR) spectrum, ultraviolet (UV) spectrum, X-ray powder diffraction, and thermal ***, UV spectra, and X-ray powder diffraction studies show that the structure of the heteropolycomplexes is a square antiprism consisting of eight oxygen atoms of two GeW_9Mo_2O_(3.)^(8-)heteropolyanions and a lanthanide ion. The thermostability of heteropoly complexes is lower thanthat of saturated Keggin structure dodecatungstogermanate.

关键词： inorganic chemistry heteropoly complex chemical synthesis lanthanates germanium

Nanostructured Columns from Self-assemblyof Complementary Molecular Components

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Chemical Research in Chinese Universities 2001年第2期17卷 193-197页

作者： YANG Wen-sheng ,YANG Bai-quan, JIANG Yue-shun and LI Tie-jin (department of chemistry, jilin {3., Changchun, 13.023. P. R. china) LIU Ya-Juan (Institute of Information Technology, jilin Agriculture {3., Changchun, 13.118, P. R. china) 吉林大学吉林长春 130023 吉林农业大学吉林长春 130118

Nanostructured columns with a length about several tens of micrometer and a diameter of about 80 nm were obtained by molecular recognition directed self-assembly of a pair of comple- mentary molecular components, 4-amino-2 , 6-didodecylamino-1 , 3. 5-triazine(M) and 5- (4-dode- cyloxybenzylidene )-(1H, 3.)-2, 4, 6-pyrimidinetrione (B) in chloroform. In this system, with positive cooperativity, π-aromatic stacking and van der Waals interactions as well as hydrogen bonds cause the formation of the nanocolumns.

关键词： Nanocolumn Self-assembly π-aromatic stacking Molecular recognition

The Synthesis of Single Crystals of Manganese Aluminophosphate Molecular Sieve and Studies on Their Properties

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Chemical Research in Chinese Universities 1989年第1期5卷 1-7页

作者： Han Shuyun and Zhou Jianrong(department of chemistry, jilin {3., Changchun)

Single crystals of the molecular sieve, MnAPO-5, were synthesized by hydrothermal synthesis in the presence of fluoride ions. It was shown by X-ray diffraction, infrared spectroscopy, electron paramagnetic resonance spectroscopy, electron probe analysis and chemical composition analysis that the structure of MnAPO-5 is of the A1PO-5 type, and manganese(Ⅱ) is incorporated into the framework. Adsorption properties, thermal stability and surface acidity were also investigated.

关键词： Single crystal Synthesis Molecular sieve

Optimal reactions for the synthesis of superheavy nucleus ^(270)Hs

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3.& BAO Jingdong1,2 1. Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing Normal university, Beijing 100875, china 2. Physics department, Beijing Normal university, Beijing 100875, china 3. china Institute of Atomic Energy, Beijing 102413. china Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing China china Institute of Atomic Energy Beijing China Physics department Beijing Normal University Beijing China

The superheavy nucleus 270Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 248Cm(26Mg,4n)270Hs, 244Pu(3.Si,4n)270Hs, 23.U(3.S,4n)270Hs and 226Ra(48Ca,4n)270Hs using a two-parameter Smoluchowski equation. It is found from our results that 226Ra(48Ca,4n)270Hs and 23.U(3.S,4n)270Hs are two optimal reactions for the synthesis of the superheavy nucleus 270Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.

STABILITY OF POLY(N,N'-METHYLENEBISACRYLAMIDE-co-4-VINYLPYRIDINE)MICROGEL DISPERSION AND ADJUSTMENT OF THE HYDROPHOBICITY IN THE MICROGELS

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Chinese Journal of Polymer Science 2005年第6期23卷 635-642页

作者： Qing-de Chen Xing-hai Shen and Hong-cheng Gao department of Applied chemistry,College of chemistry and Molecular Engineering,Peking {3.,Beijing 100871,china department of Applied chemistry College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

In the UV-Vis spectra of pure light-scattering systems, there is an exponential relationship between absorbance and wavelength （A = Kλ^-n）. Here, the exponent n is named as flocculation-coagulation parameter. In the present paper, the effects of different additives on the stability of poly（N,N＇-methylenebisacrylamide-co-4-vinylpyridine）（poly（Bis-co-4-VP）） microgel dispersion were studied in detail via this parameter. The results showed that the stability of the dispersion mainly comes from the ionization of pyridine groups, making the microgel positively charged on its surface. This was confirmed by the measurement of Zeta potential and the result of conductometric titration. The result of fluorescence analysis indicated that the hydrophobicity in the microgels is enhanced with the increase in total 4-VP unit content.

关键词： Microgel dispersion(s) 4-Vinylpyridine Flocculation-coagulation parameter Zeta potential

PROPERTIES　OF　（***）　BO_3.　Eu^（3.）PHOSPHORS　SYNTHESIZED　BY　MICROWAVE　HEATING　METHOD

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Chinese Chemical Letters 1996年第4期7卷 387-388页

作者： Yuan Ying LI Ming LI PENG(department of Chehemistry, Zhongshan university, GuangZhou, 510275)Shou Hua FENG(department of {3., jilin university, Changchun. 13.023. department of chemistry Zhongshan University Guangzhou 510275 department of chemistry Juin University Changchun 130023

In this peper we have synthesized powder crystal form (Y,Gd) BO3.Eu(3.)Phosphors by microwave heating method. ItS structure belongs to hexagonal system with lattice parameters a=0.3.96,c=0. 883.. Its excitation spetra peaks at 23..0nm and 240. 0nm monitored at the emission of 589nm and 612nm respectively, the half peak width is 40nm. Under 240nm excitation the phosphors show a strons oranse-red luminescence, the fluorescent intensity ratio for I589/I612 is 1.9/1

关键词： Gd OF PROPERTIES HEATING MICROWAVE METHOD PHOSPHORS SYNTHESIZED Eu BO3

Solving the input data in error correc-tion of optical fabrication by finite Fourier coefficient algorithm

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Science china(Technological Sciences) 2006年第1期49卷 50-60页

作者： CHENG Haobo1,2, SUN Guozheng3.& FENG Zhijing2 1. department of Optical Engineering, Beijing Institute of Technology, Beijing 100081, china 2. department of Precision Instruments and Mechanology, Tsinghua {3., Beijing 100084, china 3. china North Industries Group Corporation, Beijing 100089, china department of Optical Engineering Beijing Institute of Technology Beijing China department of Precision Instruments and Mechanology Tsinghua University Beijing China china North Industries Group Corporation Beijing China

A free-form lens (FFL) is a special surface that is difficult to be fabricated. FFL are usually fabricated by computer-controlled optical surfacing (CCOS) technique. During CCOS, the material removal amount is determined by the unit removal function (URF) convoluting with the input data――the dwell time. When the removal amount and the URF are known, how to solve the input data involves the special algorithm――deconvolution. Usually, the input data are solved by virtue of low pass filter or iterative methods. However, an approximation solution would destroy the machining stability nec-essary to perform precisely CCOS. In this paper, to solve the input data, a new method that is based on the finite Fourier coefficient is put forward. It can give a continuous and accurate solution for fabricating choice. Several parameters are simulated, which influ-ence the process of CCOS, and evaluating on the effect of the method is also carried out. Experimental results verify that this method is suitable for guiding the manufacturing of high precision FFL.

关键词： optical fabrication, computer controlled optical surfacing, free-form lens, finite Fourier coefficient, error correction.

DYNAMIC OPTIMIZATION FOR UNCERTAIN STRUCTURES USING INTERVAL METHOD

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Acta Mechanica Solida Sinica 2003年第2期16卷 141-146页

作者： Chen Suhuan Wu Jie Liu Chun (department of Mechanics,jilin university,Changchun 13.025,{3.) department of Mechanics Jilin University Changchun 130025 China

An interval optimization method for the dynamic response of structures with inter- val parameters is *** matrices of structures with interval parameters are ***- bining the interval extension with the perturbation,the method for interval dynamic response analysis is *** interval optimization problem is transformed into a corresponding de- terministic *** the mean values and the uncertainties of the interval parameters can be elected design variables,more information of the optimization results can be obtained by the present method than that obtained by the deterministic *** present method is implemented for a truss *** numerical results show that the method is effective.

关键词： interval optimization interval parameter structure interval extension of function dynamic interval response

On higher analogues of Courant algebroids

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Science china Mathematics 2011年第3期54卷 437-447页

作者： BI YanHui1 & SHENG YunHe2,3.1department of Mathematics and LMAM, Peking university, Beijing 100871, china 2School of Mathematics, {3. university, Changchun 13.012, china 3.chool of Mathematics, Dalian university of Technology, Dalian 116024, china department of Mathematics and LMAM Peking University Beijing China School of Mathematics Jilin University Changchun China School of Mathematics Dalian University of Technology Dalian China

In this paper, we study the algebraic properties of the higher analogues of Courant algebroid structures on the direct sum bundle TM ⊕∧nT*M for an m-dimensional manifold. As an application, we revisit Nambu-Poisson structures and multisymplectic structures. We prove that the graph of an (n + 1)-vector field π is closed under the higher-order Dorfman bracket iff π is a Nambu-Poisson structure. Consequently, there is an induced Leibniz algebroid structure on ∧nT*M. The graph of an (n+1)-form ω is closed under the higher-order Dorfman bracket iff ω is a premultisymplectic structure of order n, i.e., dω = 0. Furthermore, there is a Lie algebroid structure on the admissible bundle A  ∧nT*M. In particular, for a 2-plectic structure, it induces the Lie 2-algebra structure given in (Baez, Hoffnung and Rogers, 2010).

关键词： higher analogues of Courant algebroids multisymplectic structures Nambu-Poisson structures Leibniz algebroids