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Synthesis and characterization of new biodegradable thermosensitive polyphosphazenes with lactic acid ester and methoxyethoxyethoxy side groups

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Chinese Chemical Letters 2010年第2期21卷 237-241页

作者： Bi, Yun Mei Gong, Xiao Ying Wang, Wen Zhao Yu, Li Hu, Min Qi Shao, Li Dong Yunnan Normal Univ Coll Chem & Engn Kunming 650092 Peoples R China Chongqing coll Sci & Technol Coll Chem & Chem Engn Chongqing 40042 Peoples R China

Two novel biodegradable thermosensitive polyphosphazenes with lactic acid ester and methoxyethoxyethoxy side groups were synthesized via the macromolecular substitution reactions of poly(dichlorophosphazene) with the sodium salt of lactic acid ester and sodium methoxyethoxyethoxide.Their structures were confirmed by ^(31)p NMR,~1H NMR,^(13)C NMR,IR,DSC,and elemental analysis.The lower critical solution temperature(LCST) behavior in water and in vitro degradation property of the polymers was investigated.The...

关键词： Polyphosphazene Lactic acid ester Methoxyethoxyethoxy Biodegradation Thermosensitive polymer

Influence of Granularity and Content of Tungsten Carbide by Surfacing with Flux-cored Wire on Structure and Wear Resistance

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稀有金属材料与工程 2011年第S3期40卷 107-110页

作者： Li Lianjie, Gui Chibin, Dai Le Naval University of Engineering, Wuhan 430033, China Naval Univ engn Coll Ship & Power Engn Wuhan 430033 Peoples R China

The wire was made with foundry tungsten carbide particles as core. Iron-based tungsten carbide wearable composite coatings of different granularity and content on mild steel were prepared by the method of MIG welding. Microstructure of the welded coating was investigated. Surface hardness and wear resistance to rubber wheel were tested. The results indicate that the small particles dissolved more, which separate out with net on crystal boundary. As a result the hardness and wear resistance of that matrix are relative higher. The big particles dissolved less and tree crystal separates out along particles. The gaps of particles are big and the particles tend to fall off when the coating is worn. So the hardness and wear resistance of the matrix are relative lower. The admixture with 80% big particles and 20% small particles has the best wear resistance and its wear resistance is quintupling of that of quenched 45 steel. With particles content up to 50wt%, the hardness and wear resistance increase.

关键词： tungsten carbide surfacing flux-cored wire wear

SCATTERING FAR FIELD SOLUTION OF SH-WAVE BY MOVABLE RIGID CYLINDRICAL INTERFACE INCLUSION

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Acta Mechanica Solida Sinica 2002年第3期15卷 214-226页

作者： Yang Zailin Liu Diankui Shi Wenpu Harbin engn Univ Civil Engn Coll Harbin 150001 Peoples R China

The Green's function is used to solve the scattering far fieldsolution of SH-wave by a mov- able rigid cylindrical interfaceinclusion in a linear elastic body. First, a suitable Green'sfunction is devel- oped, which is the fundamental displacementsolution of an elastic half space with a movable rigid half-cylin-drical inclusion impacted by out-of-plane harmonic line source loadedat any point of its horizontal surface.

关键词： movable rigid cylindrical interface inclusion Green's function scatteringof SH-waves displacement mode of scattering wave for far field

Application of Functionalized N,S-Ketene Acetals Microwave- Assisted Three-Component Domino Reaction for Rapid Direct Access to Imidazo[1,2-a]pyridines

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Chinese Journal of Chemistry 2013年第8期31卷 1033-1038页

作者： Li, Ming Li, Tengfei Zhao, Kelong Wang, Mingda Wen, Lirong Qingdao Univ Sci & Technol Coll Chem & Mol Engn Qingdao 266042 Shandong Peoples R China

Imidazo[1,2-a]pyridines have been successfully synthesized in moderate to good yields via a tandem three- component reaction of ethyl 2-（3-oxo-3-arylpropanethioamido）acetates with aromatic aldehydes and malononitrile by means of microwave irradiation using DABCO as the catalyst. The advantages of this method including high chemo- and regioselectivity make this new strategy highly attractive.

关键词： imidazo[1,2-a]pyridines N,S-ketene acetals multicomponent reaction domino reaction microwaveirradiation

Numerical Study of Steam-Water Separators with Wave-type Vanes

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Chinese Journal of Chemical Engineering 2007年第4期15卷 492-498页

作者：李嘉黄素逸王晓墨 Huazhong Univ Sci & Technol Coll Power Engn Wuhan 430074 Peoples R China

Droplet behavior in the wave-type flow channel is discussed,especially with the secondary droplet gen- eration due to impingement of droplets on the wall considered.A numerical method is suggested to simulate the droplet behavior in the flow field.Calculations are compared with experimental data on the pressure drop and sepa- rating efficiency.Good agreement exists between the calculations and air-water experiments.The numerical method developed gives a reasonable description of the droplet deposition and secondary droplet generation,and it can be applied to predict the performance of wave-type vane separators.

关键词：水蒸气隔离器多相流动波型羽片数字方法

Synthesis and characterization of Li_(1.3)Al_(0.3)Ti_(1.7)(PO_4)_3-coated LiMn_2O_4 by wet chemical route

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Rare Metals 2009年第2期28卷 122-126页

作者： Wu Xianming Li Runxiu Chen Shang He Zeqiang Jishou Univ Coll Chem & Chem Engn Jishou 416000 Peoples R China

Li1.3Al0.3Ti1.7(PO4)3-coated LiMn2O4 was prepared by wet chemical route. The phase,surface morphology,and electrochemical properties of the prepared powders were characterized by X-ray diffraction,scanning electron micrograph,and galvanostatic charge-discharge experiments. Li1.3Al0.3Ti1.7(PO4)3-coated LiMn2O4 has similar X-ray diffraction patterns as LiMn2O4. The corner and border of Li1.3Al0.3Ti1.7(PO4)3-coated LiMn2O4 particles are not as clear as the uncoated one. The two powders show similar values of lithiumion diffusion coefficient. When cycled at room temperature and 55°C for 40 times at the charge-discharge rate of 0.2C,Li1.3Al0.3Ti1.7(PO4)3-coated LiMn2O4 shows the capacity retentions of 98.2% and 93.9%,respectively,which are considerably higher than the values of 85.4% and 79.1% for the uncoated one. Both the capacity retention differences between Li1.3Al0.3Ti1.7(PO4)3-coated LiMn2O4 and LiMn2O4 cycling at room temperature and 55°C become larger with the increase of charge-discharge rate. When the charge-discharge rate reaches 2C,the capacity retention of LATP-coated LiMn2O4 becomes 8.4% higher than the uncoated LiMn2O4 for room temperature cycling,and it becomes 11.1% higher than the latter when cycled at 55°C.

关键词： lithium ion battery coating electrochemistry solid state electrolyte intercalation compounds

Performance tests of multi-metal zincate solutions with zinc sulfate and zinc oxide

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Rare Metals 2007年第S1期26卷 99-104页

作者： HUANG Xiaomei,and ZHANG Milin college of Materials Science and Chemical Engineering,Harbin Engineering University,Harbin 150001,China Harbin engn Univ Coll Mat Sci & Chem Engn Harbin 150001 Peoples R China

Morphology of zinc alloy layer,from zincate solution with zinc sulfate and zinc oxide respectively,together with the consequent deposit was observed with SEM and back scattering electron image.EDS was applied to analyze the components of zinc alloy layer and the interface of high-Si aluminum alloy substrate-zinc alloy-deposit.Besides,the surface morphology of the zincated aluminum alloy after immersing in 3.5% NaCl solution for 7 d,is observed and the corrosion rate was calculate.Finally,tension test is conducted to quantify the adhesion between high-Si aluminum cast substrate and the deposit.The results show that,the zinc oxide contained zincating solution with sodium potassium tartrate and sodium citrate is a better one in multi-metal zincating solutions.The zinc alloy layer from this one gets stable performance,perfect adhesion with deposit,and good corrosion resistance.

关键词： Al-Si alloy multi-metal zincating solution adhesion

Detection of hydroxyl radical in plasma reaction on toluene removal

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Journal of Environmental Sciences 2008年第12期20卷 1429-1432页

作者： Guo Yufang Liao Xiaobin Ye Daiqi Guangzhou Univ Guangzhou Higher Educ Mega Ctr Coll Environm Sci & Engn Guangzhou 510006 Guangdong Peoples R China S China Univ Technol Guangzhou Higher Educ Mega Ctr Coll Environm Sci & Engn Guangzhou 510006 Guangdong Peoples R China

A new method was introduced to detect the concentration of OH radical in dielectric barrier discharge(DBD)reaction.A film, which was impregnated with salicylic acid,was used to detect OH radical in plasma reaction at room temperature and atmospheric pressure.Salicylic acid reacts with OH radical and produces 2,5-dihydroxybenzoic acid(2,5-DHBA).Then,a high performance liquid chromatography(HPLC)was carried out to detect the concentration of 2,5-DHBA.Therefore,OH radical in nonthermal plasma reaction could be...

关键词： OH radical detection nonthermal plasma toluene

THE SHRINKAGE OF EXPANSIVE CONCRETE FILLED STEEL TUBE AND ITS IMPROVEMENT METHOD

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Journal of Wuhan University of Technology(Materials Science) 1999年第1期14卷 46-51页

作者： Li, Y Hu, SG Ding, QJ Zhou, MK Zhang, YS Wuhan Univ Technol Coll Mat & Engn Wuhan 430070 Peoples R China

The shrinkage characteristics tics of expansive concrete filled steel tube (CFST) are analyzed, Cold shrinkage, creep and autogenous shrinkage are considered as the main reasons of causing CFST contraction. In accordance with the shrinkage characteristics of expansive CFST, a kind of energy-stored delayed expansive agent is exploited, which can not only compensate the shrinkage of the core concrete in every stages, but also make CFST expand according to the delayed expansion mechanism. As the result, the prestress loss weill be reduced and expansive energy will be utilized effectively.

关键词： concrete filled steel tube shrinkage mechanism expansive agent expansive model