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Thermal analysis of the baffle structure of the Solar Space Telescope

Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1755-1764页

作者： LI Rong1,2.3 & WANG Sen1,3 1 National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100012.china 2.Graduate university of Chinese Academy of Sciences,Beijing 100049,china 3 Key Laboratory of Solar Activity,National Astronomical Observatories of Chinese Academy of Sciences,Beijing 100012.china National Astronomical Observatories Chinese Academy of Sciences Beijing China Graduate university of Chinese Academy of Sciences Beijing China Key Laboratory of Solar Activity National Astronomical Observatories of Chinese Academy of Sciences Beijing China

The SST(Space Solar Telescope) is an astronomical telescope with a primary mirror of 1 m in *** observes the sun with a small view field to ensure that its high spatial resolution imaging has 0.1″-0.15″ and high SNR(signal to noise ratio).Surrounding the small view field is still the sun,which is an intense source of both heat and stray *** baffles(the main baffle,the aperture,and the outer baffle),which are used to eliminate the stray light,will change the thermal flux in the SST and will weaken the effect of the thermal control *** this study,the compatibility analysis of the thermal effect of baffle structures in SST is *** GCF(Geometry Composing Function) and BRDF(Bidirectional Reflectance Distribution Function),which are two inherent related parameters in the compatibility analysis,are *** objective and method of the compatibility analysis are *** the thermal analysis software,the temperature fields are calculated for different lengths of the main baffle,different radii of apertures,different lengths of the outer baffle with a 3' tilt angle and 16' tilt angle,and different tilt angles of the outer baffle with a 2.0 mm length.A series of configurations and sizes of the baffles are studied with the goals of both thermal control and elimination of stray *** design of the baffle structure of SST is achieved:the main baffle of length 4100 mm,the internal shield of radius 494 mm,the outer baffle of length 2.0 mm,and the outer baffle of tilt angle 3' are successfully *** paper presents the relationship between the thermal control design and stray light elimination plan in the *** aims of the optimal design of the baffle structure of SST are *** thoughts and methods of the optimal analysis are also useful for similar optical telescopes designed for solar observation.

关键词： baffle the main baffle the outer baffle GCF BRDF

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Pulsation Treatment on the Modification of Crystal with Cold Simulation

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 20-23页

作者： Jianzhong Wang Yong Tang Daqiang Cang Jiaquan Zhang(Metallurgy School, university of Science and Technology Beijing, Beijing 100083. {2.) Metallurgy School University of Science and Technology Beijing Beijing 100083 China

Since the separation of crystal of KCl saturated aqueous is similar to the crystallization of liquid metals, the melts nucleation can be simulated by the experiment of the crystal of salt aqueous solution. In this experiment pulsation treatment was imposed on KCl saturated aqueous in order to study the effect of pulsation treatment on crystallization in the salt solution, and the influence of different pulsation treating time, super-heating and bine of prescription were investigated. The results show that it is possible to modify the crystallization over satured solution temperature and the degree of under-cooling for salt crystal separation was reduced by applying pulse treating on KCl saturated aqueous solution. In addition, this technology may generate embryos for nucleation even at the temperature over melting point or satured solubility.

关键词： saturated aqueous solution pulse modification treatment nucleation, crystal

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Effect of Nb on the Mechanical Properties of Ti/Al_2._3 Composite

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Journal of Wuhan university of Technology(Materials Science) 2005年第1期20卷 30-32,36页

作者：王志 School of Materials Science and Engineering Ji'nan University Jinan 250022China State Key Laboratory of Advanced Technology for Materials Synthesis and Proces sing Wuhan University of Techology Wuhan 430070China

Ti/Al 2. 3 composite with improved mechanical properties was synthesized by th e spark plasma sintering. The effect of Nb on the microstructure of the composit e was analyzed by TEM, SEM and so on. The experimental results indicate that the bending strength, fracture toughness, micro-hardness and relative density of t he composite are 897.2.MPa, 17.38MPa·m 1/2. 17.13GPa and 99.2.% respec tively when adding 1.5vol%Nb. The bending strength is improved by reason of form ing dislocation ring and transfering fracture mode from intergranular to mixture fracture of intergranular and transgranular. The crack propagating is mainly th e deflection bridging. It indicates a reduction of crack driving force and an in crease in crack growth resistance,which results in toughness enhanced.

关键词： spark plasma sintering Ti/Al 2. 3 composite niobium mechanical properti es

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MICROSTRUCTURE AND DUCTILITY OF RE DOPED RAPIDLY SOLIDIFIED NiAl

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Acta Metallurgica Sinica(English Letters) 1995年第2期8卷 106-109页

作者： SUN Baode LIN Dongliang YANG Gencang ZHOU Yaohe 1)Shanghai Jiao Tong university, Shanghai,china)2.Northwesten Polytechnic university,Xi’an,china Shanghai Jiaotong Univ Shanghai China

The paper investigated the effects of RE on the microstructure and ductility of melt-spun Al-63.3at.%Ni and Al-66.4at%*** Al-63.3at.%Ni without RE the microstructure is a mixture of equiaxed martensitic grains and B2.NiAl grains,but after addition of 0.2.t% RE a complete supersaturated B2.NiAl results,and its elongation is enhanced from 0.9%(without RE) to 1.4%(with 0.2.t%RE).For Al-66.4at.%Ni without RE the microstructure is coarse equiaxed martensitic grains with Ni3Al precipitated at the *** complete martensitic grains and supersaturated single phase,B2.NiAl,would result with addition of 0.05wt%RE and 0.2.0.8wt%RE *** elongation of Al-66.4at.%Ni without RE is only 0.8%.With the addition of 0.05, 0.2.and 0.8wt%*** elongation can reach 2.6,3.0 and 3.2. *** addition of RE can change the fracture mode from intergranular fracture(without RE) to a mixture of intergranular and transgranular fracture or entirely transgranular *** mechanisms of microstructure formation and ductility enhancement are analyzed.

关键词： NiAl rare earth element rapidly solidified alloy ductility

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Minimal Rank Preserving Additive Mappings on Upper Triangular Matrices

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Journal of Mathematical Research and Exposition 2011年第6期31卷 951-964页

作者： Yu GUO1,2.3,Jin Chuan HOU2.3 1.department of Mathematics,Shanxi Datong university,Shanxi 037009,P.R.{2. 2.department of Mathematics,Shanxi university,Shanxi 030006,P.R.{2. 3.department of Mathematics,Taiyuan university of Technology,Shanxi 03002.,P.R.{2. department of Mathematics Shanxi Datong University Shanxi 037009 department of Mathematics Shanxi University Shanxi 030006

The additive mappings that preserve the minimal rank on the algebra of all n × n upper triangular matrices over a field of characteristic 0 are characterized.

关键词： rank minimal rank upper triangular matrices additive mappings

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Early Age Compressive Strength of Pastes by Electrical Resistivity Method and Maturity Method

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Journal of Wuhan university of Technology(Materials Science) 2011年第5期26卷 983-989页

作者：肖莲珍 School of Materials Science and Engineering Wuhan Institute of Technology

The compressive strength development of Portland cement pastes was investigated by the electrical resistivity method and the maturity *** experiments were carried out on the cement pastes with different water-cement ratios at different curing *** results show that the application of the maturity method has limitation to obtain the *** is found that both of the compressive strength and the electrical resistivity follow hyperbolic trend for all the *** hyperbolic equation of each mix is obtained to estimate the ultimate resistivity value which can probably be *** relationship between electrical resistivity and compressive strength of the cement pastes is established based on the test results and interpreted by the empirical Archie equation and a strength-porosity *** relationship between the electrical resistivity after temperature correction and the compressive strength was linear and independent of curing temperature and water-cement ratio.

关键词： electrical resistivity cement hydration compressive strength maturity method

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Zeolite NaY-mediated oxidation of dyes with H_2._2. unique heterogeneous non-transition metal center cleavage of H_2._2.under visible light irradiation

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Science china Chemistry 2007年第6期50卷 770-775页

作者： LIU LiLi1, MA WanHong1, SONG WenJing1, CHEN ChunCheng1, LIN Jun2. ZHAO JinCai1, QIAN XinHua3 & ZHANG ShiBo3 1 Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, china 2.department of Chemistry, Renmin {2. of china, Beijing 100872. china 3 Fushun Petrochemical Company, Petrochina Company Limited, Fushun 113008, china Institute of Chemistry Chinese Academy of Sciences Beijing China department of Chemistry Renmin University of China Beijing China Fushun Petrochemical Company PetroChina Company Limited Fushun China

This study investigated the visible-light catalysis mediated by zeolite NaY on the oxidation of dyes with H2.2. The results demonstrated that zeolite NaY acts as a sink for the electron from the photo-excited dye in the heterogeneous catalysis. Furthermore, the electron can effectively activate H2.2.to produce ?OH radical that is a powerful oxidant for the oxidation of dye at room temperature. The effects of the framework topology, Si/Al ratio, and exchangeable cation of the zeolite on the oxidation of various dyes were also shown.

关键词： photooxidation, zeolite NaY, dye, hydrogen peroxide, visible light

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Synthesis of TiN/AlON composite ceramics

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Journal of university of Science and Technology Beijing 2003年第1期10卷 49-53页

作者： Xidong Wang, Lichun Gao, Guobao Li, and Wenchao Lidepartment of Physical Chemistry, university of Science and Technology Beijing, Beijing {2. china Dept. of Phys. Chem. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The synthesis process of TiN/AlON composite ceramics was studied, the thermodynamics, mechanical properties and micro-structures of TiN/AlON have also been investigated. The TiN/AlON composite ceramics has been synthesized by both hot-pressing and pressureless sintering. The characterizations of the material synthesized were analyzed with XRD (X-ray diffraction) and TEM (transmission electronic microscope). The density and toughness strength of TiN/AlON are 3.57g/cm3 and 4.74MPa.m1/2. respectively. The bending strength was measured at both room temperature and high temperatures and the results are 399 MPa (room temperature), 406 MPa (1 073 K), 417 MPa (1 2.3 K) and 32. MPa (1 573 K). Pattern Recognition (PR) and Artificial Neural Network (ANN) were used to optimize the parameters and to predict the expected values. A proper parameter for pressureless sintering of TiN/AlON has been obtained and testified, the parameters are temperature (1 978 K), AlN / (AlN + Al2.3) ratio (0.2.), MgO (4.7%) and TiO2.(7.2.).

关键词： synthesis TiN AlON composite ceramics

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A Creep Equation Based on Thermal Activation

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International Journal of Minerals,Metallurgy and Materials 1998年第1期12卷 44-46页

作者： Jiyue Sun Guoliang Chen (State Key Laboratory for Advanced Metals and Materials, university of Science and Technology Beijing, Beijing 100083. {2.) State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

The creep equation proposed in so called θ projection concept is developed in the concept of thermal activation of creep. The measured creep curves of A2.6 alloy are fitted by the equation. The activation energy in theequation is evaluated, and creep rupture lives are predicted. The results are confirmed by creep tests of up to 13years.

关键词： creep creep curve equation creep rupture life A2.6 superalloy

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INTERVAL FINITE VOLUME METHOD FOR UNCERTAINTY SIMULATION OF TWO-DIMENSIONAL RIVER WATER QUALITY

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Journal of Hydrodynamics 2004年第4期16卷 455-463页

作者： HELi ZENGGuang-ming] HUANGGuo-he LUHong-wei departmentofEnvironmentalSystemEngineering UniversityofReginaSaskatchewanS4S0A2Canada departmentofEnvironmentalScienceandEngineering HunanUniversityChangsha410082China

Under the interval uncertainties, by incorporating the discretization form offinite volume method and interval algebra theory, an Interval Finite Volume Method (IF-VM) wasdeveloped to solve water quality simulation issues for two-dimensional river when lacking effectivedata of flow velocity and flow quantity. The IFVM was practically applied to a segment of theXiangjiang River because the Project of Hunan Inland Waterway Multipurpose must be started workingafter the environmental impact assessment for it. The simulation results suggest that there existrather apparent pollution zones of BOD_5 downstream the Dongqiaogang discharger and that of CODdownstream Xiaoxiangjie discharger, but the pollution sources have no impact on the safety of thethree water plants located in this river segment. Although the developed IFVM is to be perfected, itis still a powerful tool under interval uncertainties for water environmental impact assessment,risk analysis, and water quality planning, etc. besides water quality simulation studied in thispaper.

关键词： interval finite volume method (IFVM) uncertainty simulation water quality

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