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Two-photon Induced UV Fluorescence in Photo-active Spiropyran Molecules

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Chinese Journal of Lasers 1995年第2期B4卷 101-104页

作者： CHI Lunguang WANG Zugeng(department of Physics, East china Normal university,Joint Laboratory for Quantum Optics, Shanghai Institute of Optics &. Fine mechanics,Academia Sinica and East china Normal university, Shanghai 200062, china) East china Normal Univ Shanghai China

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关键词： spiropyran merocyanine two-photon absorption UV fluorescence

Condensation Reaction of α-Aroyl-α-acetyl Ketene Cyclic Dithioacetals with Aromatic Aldehydes

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Chinese Chemical Letters 1999年第1期10卷 5-6页

作者： Zhong Wei XIE Qun Xin FANG Yu Lan HU Met Xin ZHAO Dong YU Qun LIU(department of chemistry, Northeast Normal university, Changchun, 13.024) department of chemistry Northeast Normal University Changchun 130024 China

The title compounds 3.and 4 condensed with aromatic aldehydes to give a--aroylsicinnamoyl ketene cyclic dithioacetals 5 and 6 with sodium ethoxide as the base. The stereochemistryofs and 6 was assigned as E-configurat... 详细信息

关键词： α-aroyl-α-cinnamoyl ketene cyclic dithioacetals,aromatic,aldehydes condensation reaction

Effect of Sintering on the Magnetism and Magnetoresistance of La_(1/3.Nd_(1/3.Ca_(1/3. MnO_3

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Journal of Materials Science & Technology 2000年第2期16卷 161-162页

作者： Guoqing LI, Lijie HAO, Ze XIANYU, Deren LI, Ke SUN and Halving LI (department of Physics, Northeastern university, Shenyang 110006, china) department of Physics Northeastern University Shenyang 110006 China

Perovskite-like bulk La_1/3.d_1/3.a_1/3.nO_3.is prepared by solid phase reaction method. The temperature dependence of the magnetization and the relationship between CMR effect and sintering have been studied. The CMR is up to 673.9% under 1 T applied magnetic field and 100 K temperature, and that also reaches 93.5% in 0.2 T and 100 K.

关键词： MnO3 Effect of Sintering on the Magnetism and Magnetoresistance of La Nd Ca

Studies on Blends of Nylon 6 and a Thermotropic Liquid Crystalline Polyarylester(Ⅱ)——Morphology and Rheology

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Chemical Research in Chinese Universities 1992年第2期8卷 121-125页

作者： WANG Xia-yu and XIONG Qian-zheng (department of chemistry, Xiangtan university, Xiangtan, 411005)

Blends of nylon 6 (PA6) and a semirigid thermotropic liquid crystalline polyarylester (THH) were prepared by coprecipitation. The changing of the morphology of the blends with their compositions was observed by means of a polarizing microscope and scanning electron microscope. The THH phases in the blends changed gradually from spherical droplets to fibrils with the increase of THH content. The flow behavior of the blends are quite different from that of the parent polymers and a very dramatic reduction in the melt viscosity of blends containing 5% THH was observed. The formation possibility of in-situ reinforcement composites of PA6 blends with a semirigid LCP is discussed in the present paper.

关键词： Blend Thermotropic Morphology Rheology

Study on Molecular Chain Morphology of Konjac Glucomannan

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Agricultural Sciences in china 2003年第7期2卷 798-803页

作者： LI Bin and XIE Bi-jun(Natural Product chemistry Research Laboratory , Food Science department, Huazhong Agricultural university , Wuhan 43.070, P. R.{3.) Natural Product chemistry Research Laboratory Food Science Department Huazhong Agricultural University Wuhan 430070 P. R. China

The long-range structure of konjac glucomannan(KGM)is studied by using laser light scatter(LLS), gel permeation chromatography(GPC)and method of viscosidity. The weight-average molecular weight(Mw), root-mean-square ratio of gyration[(S2)1/2], second viral coefficient(A2)and multi-dispersion coefficient(Mw/Mn)are 1.04×106, 105. 0±0. 9 nm,(-1. 59±0.28)×10-3.mol ml g-2 and 1.015±0.003. respectively. Mark-Houwink equation is established as [η] = 5. 96×10-2Mw0.73.and the molecular chain parameters are as follows: ML=982. 82 nm-1, Lp = 27. 93.nm, d = 0. 74 nm, h = 0. 26 nm, L = l 054.11 nm. Further more molecular chain morphology of KGM is studied by using atom force microscope(AFM)and transmission electronic microscope(TEM), and the result shows that the KGM molecular is an extending semi-flexible linear chain without branch. Therefore, the image of molecular chain morphology confirms the deduction drawn by Mark-Houwink equation and molecular chain parameters.

关键词： Konjac glucomannan Molecular chain parameter Molecular morphology Laser light scatter Atom force microscope

Effect of carbon source on the denitrification in constructed wetlands

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Journal of Environmental Sciences 2009年第8期21卷 1036-1043页

作者： LU Songliu, HU Hongying, SUN Yingxue, YANG Jia ESPC State Key Joint Laboratory, department of Environmental Science and Engineering, Tsinghua university, Beijing 100084, china. ESPC State Key Joint Laboratory Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China

The ability of constructed wetlands with different plants in nitrate removal were investigated. The factors promoting the rates of denitrification including organic carbon, nitrate load, plants in wetlands, pH and water temperature in field were systematically investigated. The results showed that the additional carbon source （glucose） can remarkably improve the nitrate removal ability of the constructed wetland. It demonstrated that the nitrate removal rate can increase from 20% to more than 50% in summer and from 10% to 3.% in winter, when the nitrate concentration was 3.-40 rag/L, the retention time was 24 h and 25 mg/L dissolved organic carbon （DOC） was ploughed into the constructed wetland. However, the nitrite in the constructed wetland accumulated a little with the supply of the additional carbon source in summer and winter, and it increased from 0.15 to 2 mg/L in the effluent. It was also found that the abilities of plant in adjusting pH and temperature can result in an increase of denitrification in wetlands. The seasonal change may also impact the denitrification.

关键词： constructed wetland carbon source denitrification nitrate nitrite

Interpolating triangular meshes by Loop subdivision scheme

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Science china(Information Sciences) 2010年第9期53卷 1765-1773页

作者： DENG ChongYang1* & WANG GuoZhao2 1Institute of Applied Mathematics and Engineering Computations,Hangzhou Dianzi university,Hangzhou 3.0018,china 2department of Mathematics,Zhejiang university,Hangzhou 3.0027,china Institute of Applied Mathematics and Engineering Computations Hangzhou Dianzi University Hangzhou China department of Mathematics Zhejiang University Hangzhou China

Using the limit point formula of the Loop subdivision scheme,we propose a very simple and efficient method for constructing interpolation surface of triangular meshes by Loop subdivision *** excellent properties of the method are:(1) Locality:the perturbation of a given vertex only influences the surface shape near this vertex.(2) Efficiency:the locations of new points can be computed with explicit formulae.(3. Easiness in implementation:only the geometric rule of the first step should be modified.(4) Freedom:for each edge,there is one degree of freedom to adjust the shape of the interpolation surface.(5) Easiness in generalization:it is easy to generalize our method to other approximation subdivision schemes with explicit formulae to compute limit point.

关键词： computer aided geometric design subdivision surface approximating subdivision scheme Loop surface surface interpolating

MACKEY TOPOLOGIES OF HARDY SPACES AND BERGMAN SPACES IN SEVERAL COMPLEX VARIABLES

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Chinese Science Bulletin 1989年第19期34卷 1585-1589页

作者：史济怀 department of Mathematics University of Science and Technology of China Hefei

B_n denotes the unit ball of C^n,(?)B_n its boundary, γ_n,and σ_n the normalized Lebesgue measures on B_n and (?)B_n respectively, H(B_n) the class of all functions holomorphic in B_n.

关键词： Mackey topology dual locally convex

Dynamics of risers for earthquake resistant designs

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Petroleum Science 2010年第2期7卷 273-282页

作者： Duan Menglan Wang Yi Yue Zhiyong Estefen Segen Yang Xiaogang School of Naval Architecture and Marine Engineering Dalian University of Technology Dalian Liaoning 116024 China Offshore Oil/Gas Research Center China University of Petroleum Beijing 102249 China department of Mechanics and Engineering Peking University Beijing 100080 China COPPE Federal University of Rio de Janeiro EO.Box 68508 RJ 21945-970 Brazil Design Division CNOOC Engineering Tanggu Tianjin 300452 China

It is well known that no criterion about seismic design for risers is available, and relevant research has not been reported. A comprehensive study of riser dynamics during earthquakes is performed in this paper. A dynamic model for seismic analysis of risers is developed in accordance with the working environment of the risers and the influence of inertia force of the pipelines. The dynamic equations for the developed model are derived and resolved on the basis of the energy theory of beams. Numerical simulation for an engineering project in the Bohai Oil Field, china shows that the fundamental frequency of the riser plays the major role in the seismic responses, and for platforms in shallow water in Bohai Bay, the risers demonstrate a much lower stress response due to prominent differences between the riser frequency and the earthquake wave frequency. The presented model and its corresponding method for seismic analysis are practical and important for riser design resistant to earthquake waves.

关键词： Subsea pipeline riser seismic design dynamic response earthquake wave Hamilton theory