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Synthesis of 2H-3,1-pyrazolo[3,4-e]oxazines via a new conversion of Friedlander reaction

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Chinese Chemical Letters 2007年第6期18卷 636-638页

作者： Li, Jia Rong Zhang, Li Jun Chen, Jin Nan Yang, Xi Quan Wang, Li Jun Zhao, Xiao Fan Qiu, Jun Xia beijing inst technol Sch Chem Engn & Environm Beijing 100081 Peoples R China

2H-3,l-Pyrazolo[3,4-e]oxazines (5a-c) and tacrine analogies (6a-c) were designed and prepared using 5-amino-4-cyanopyrazole (7) and cycloketones (2a-c) as reactants. The study demonstrated that the new conversion existed in the Friedlander reaction of o-aminocyanopyrazole with cycloketones. (C) 2007 Jia Rong Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： pyrazole oxazines tacrine cyclocondensation synthesis

The Influence of Laser Shock Processing to TC4 Titanium Alloy TIG Welding Bead Microstructure and Properties

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稀有金属材料与工程 2011年第S4期40卷 206-210页

作者： Xu Haiying,Che Zhegang,Zou Shikun,Cao Ziwen Science and technology on Power Beam Processes Laboratory,beijing Aeronautical Manufacturing technology Research institute,beijing 100024,China beijing Aeronaut Mfg technol Res inst Sci & Technol Power Beam Proc Lab Beijing 100024 Peoples R China

TC4 titanium tungsten inert gas arc (TIG) weld beads were treated by laser shock processing (LSP) *** a single and multiple times LSP introduced,surface hardness,tensile mechanical properties and fatigue life of those weld joints were *** results showed that:compared with TC4 titanium alloy TIG joints without LSP treatment,those weld beads surface hardness on weld zone and heat affected zone are nearly *** fatigue life of those TC4 TIG weld joints treated by a single time LSP process is *** the LSP times increased,TC4 titanium alloy weld beads tensile strength and yield strength are not obviously *** special elongation of these welding joints treated by different times LSP treatment will be influenced *** elongation of those joints is decreased with the LSP treatment times increased from one to *** welding joint special elongation was reduced to the least degree since three times LSP treatment had been introduced.

关键词： laser shock processing titanium alloy HV hardness tensile properties fatigue life

Rheological Behavior for Polymer Melts and Concentrated Solutions——Part Ⅶ: A Quantitative Verification for the Molecular Theory of Non-linear Viscoelasticity with Entanglement Constraints in Polymer Melts

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Journal of Materials Science & technology 2001年第3期17卷 375-382页

作者： Mingshi SONG, Chen ZHANG and Guixian HU Research institute of Polymeric Materials, beijing University of Chemical technology, beijing 100029, China E-mail: wangzhchen@*** Res. inst. of Polymeric Mat. Beijing Univ. of Chem. Technol. Beijing 100029 China

Based on the molecular theory of non-linear viscoelasticity with constrained entanglements in polymer melts, the material functions in simple shear flow were formulated, the theoretical relations between. eta((gamma) over dot), psi (10)((gamma) over dot) and shear rate ((gamma) over dot), and topologically constrained dimension number n ' and a were derived. Linear viscoelastic parameters (eta (0) and G(N)(0)) and topologically constrained dimension number (n ' a and )over bar>) as a function of the primary molecular weight (M-n), molecular weight between entanglements (M-C) and the entanglement sites sequence distribution in polymer chain were determined. A new method for determination of viscoelastic parameters (eta (0), psi (10), G(N)(0) and J(e)(0)), topologically constrained dimension number (n ', a and v) and molecular weight (M-n, M-c and M-e) from the shear flow measurements was proposed. It was used to determine those parameters and structures of HDPE, making a good agreement between these values and those obtained by other methods. The agreement affords a quantitative verification for the molecular theory of nonlinear viscoelasticity with constrained entanglement in polymer melts.

关键词： Rheological Behavior for Polymer Melts and Concentrated Solutions A Quantitative Verification for the Molecular Theory of Non-linear Viscoelasticity with Entanglement Constraints in Polymer Melts Part

Characteristics of Joint Welded by Laser Welding of Aluminium-Lithium Alloy with Filler Wire

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稀有金属材料与工程 2011年第S4期40卷 138-141页

作者： Yang J1,2,Li X Y1,Gong S L2,Chen L2,Xu F2 1 School of Material Science and Engineering,beijing University of technology,beijing 100083,China 2 Science and technology on Power Beam Processes Laboratory,beijing Aeronautical Manufacturing technology Research institute,beijing 100024,China beijing Aeronaut Mfg technol Res inst Sci & Technol Power Beam Proc Lab Beijing 100024 Peoples R China beijing Univ technol Sch Mat Sci & Engn Beijing 100083 Peoples R China

The characteristics of weld shape,microstructure,mechanical properties and defects of 5A90 Al-Li alloy joint by laser welding (LBW) and laser welding with filler wire (LWFW) were studied and *** results indicated that the microstructure of joint by LWFW was fine-grained layer and the equiaxed grain in most of seams,which were similar to the joint by *** with the joint by LBW,the microstructure of joint by LWFW tended to fine,and the range of the columnar crystals zone was prone to *** Microhardness of the joint by LWFW (92.57HV0.2) was lower than that by LBW (95.65HV0.2),but the uniformity was *** ultimate tensile strength of the joint by LWFW was lower than that by LBW slightly,which reached to 73.03% and 79.22% of the base metal ***,the elongation of the LWFW joint was higher than that of the LBW joint significantly,which reached to 38.65% and 20.38% of the base metal *** microstructure and mechanical properties of 5A90 Al-Li alloy by LWFW were better than that by *** defects of joint were mainly forming defects which were caused by improper parameters and porosity inside the joint,which was caused by uncleaned surface and incomplete penetration.

关键词： Al-Li alloy laser beam welding (LBW) laser welding with filler wire (LWFW) weld shape microstructure mechani-cal properties defects

Investigation on the Effect of Electron Beam Weld Shape on Fatigue Performance of Thickness Titanium Alloy

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稀有金属材料与工程 2011年第S4期40卷 125-129页

作者： Liu Xin1,2,Gong Shuili2,Lei Yongping1 1School of Material Science and Engineering,beijing University of technology,beijing 100021,China2Science and technology on Power Beam Processes Laboratory,beijing Aeronautical Manufacturing technology Research institute,beijing 100024,China beijing Univ technol Sch Mat Sci & Engn Beijing 100021 Peoples R China beijing Aeronaut Mfg technol Res inst Sci & Technol Power Beam Proc Lab Beijing 100024 Peoples R China

Different weld shapes of 45mm thickness TA15 titanium alloy were obtained by choosing appropriate electron beam welding parameters,and the influence of weld shape on fatigue performance of the joints was investigated by analytic hierarchy *** results show that four typical weld shapes were formed,according to their geometry characters,which are respectively named as bell shape,funnel shape,nail shape,and wedge *** shape effect the fatigue life and dispersion of the experiment data of the *** sequencing of fatigue performance of the joints with four different shapes by analytic hierarchy mathematical model is bell shape,funnel shape,wedge shape,and nail *** is validated by trial results that the analytic hierarchy mathematical model is effective and practical.

关键词： weld shape fatigue performance analytic hierarchy process electron beam welding thickness titanium alloy

Microstructure and Texture Characterization in Nd:YAG Laser Welds of 5A90 Aluminum-Lithium Alloys

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稀有金属材料与工程 2011年第S4期40卷 39-43页

作者： Cui Li1,Li Xiaoyan1,He Dingyong1,Chen Li2,Gong Shuili21College of Materials Science and Engineering,beijing University of technology,beijing 100124,China2Science and technology on Power Beam Processes Laboratory,beijing Aeronautical Manufacturing technology Research institute,beijing 100024,China beijing Univ technol Coll Mat Sci & Engn Beijing 100124 Peoples R China beijing Aeronaut Mfg technol Res inst Sci & Technol Power Beam Proc Lab Beijing 100024 Peoples R China

Microstructure and texture characterization in Nd:YAG laser welds of 5A90 Aluminum-Lithium (Al-Li) alloys were studied by means of optical microscope (OM),electron back scattered diffraction (EBSD) and transmission electron microscope (TEM).The solidification structure,misorientation angle,dislocation density and microtexture of the welds in 5A90 Al-Li alloys were investigated and compared with the unaffected base *** results show that microstructure and texture changes of the 5A90 Al-Li alloy after laser *** solidification structure results show that a zone of equiaxed grains (EQZ) along the fusion boundary is formed and the weld metal exhibits entirely equiaxed dendritic grains for 5A90 Al-Li *** study clearly shows the high angle boundaries (>15°) and microtexture changes for 5A90 Al-Li alloy after laser *** images indicate that the laser welding has no influence on the dislocation density.

关键词： laser welding Al-Li alloy microstructure texture EBSD

Synthesis and Structure of A Novel Caged Bicyclic Phosphate Flame Retardant

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Chinese Chemical Letters 2000年第10期11卷 887-890页

作者： Li, X Ou, YX Zhang, YH Lian, DJ beijing inst technol Natl Lab Flame Retarded Mat Beijing 100081 Peoples R China

PI novel caged bicyclic phosphate flame retardant tri(1-oxo-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octane-methyl) phosphate (Trimer) was synthesized from 1-oxo-4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octane (PEPA) and phosphorus oxychloride in this paper. Its structure was characterized by elemental analysis. FTIR, H-1 NMR. P-31 NMR and X-ray diffraction analysis.

关键词： caged bicyclic phosphate flame retardant crystal structure

NOVEL OXIDATION OF HEXABENZYLHEXAAZA-ISOWURTZITANE BY Me_2CHNO_2/CuCl/Py/O_2

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Chinese Chemical Letters 1996年第6期7卷 511-512页

作者： Guan, XP Yan, H Sun, JG Yu, YZ beijing inst technol SCH CHEM ENGN & MAT SCIBEIJING 100081PEOPLES R CHINA

Treatheent of2.4. 6. 8, 10.12-hexahany1-2.4. 6, 8,10, 12-hexaazateteracyclo [5.***.0.03.9 03.11]dodecane (1) with ***2/CuCl/Py/O2 results in C(1)-C(7) okidative cleavop to give 1,3.4,5,7,8-hexabenzy-2,6-dioxo-cis-cisid... 详细信息

关键词： CuCl Me2CHNO2 ISOWURTZITANE BY NOVEL OF OXIDATION Py

Rheological Behaviors of Polymer Melts and Concentrated Solutions Part VI: Comparison of the Material Functions with Yielding and Thinning for Polymeric Suspensions with Their Experimental Values

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Journal of Materials Science & technology 1999年第3期15卷 251-252,523-262页

作者： Song, MS Zhou, W Hu, GXX Hu, LJ beijing Univ Chem technol Res Inst Polymer Mat Beijing 100029 Peoples R China Harbin inst technol Dept Appl Chem Harbin 150001 Peoples R China

The memory function and elastic modulus were introduced into the O-W-F type of constitutive equations with the Cauchy-Green and Finger tensors for simple fluid, and then the concrete constitutive equation and material function for polymeric suspensions in the different flow fields were formulated: 1) Viscosity and first normal-stress difference coefficient in the shear flow field; 2) Tensile viscosity at the uni-axial elongation flow field; and 3) Dynamic viscosity and modulus in the dynamic field. Then the dependence of the material function on the deformation rate and weight fraction of fillers was discussed, and the shear flow curves with four characteristic regions ( I-low shear rate plateau region, II- apparent yielding region, ill-intermediate rate plateau region, and lV-shear thinning region.) were explained theoretically. Finally, it was verified by a number of experimental values for the rheological suspensions and the viscoelastic and mechanical behaviors can be predicted by the molecular theory of non-linear viscoelasticity for polymeric suspension;.

关键词： Th Comparison of the Material Functions with Yielding and Thinning for Polymeric Suspensions with Their Experimental Values Rheological Behaviors of Polymer Melts and Concentrated Solutions Part VI