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Microwave-promoted solvent-free synthesis of N-(diphenylmethylene)glycine alkyl esters

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Chinese Chemical Letters 2009年第12期20卷 1405-1407页

作者： Quan Jun Wang Wei He Qiao Feng Wang Xin Shi Xiao Li sun sheng yong Zhang Department of Chemistry Fourth Military Medical University Xi'an 710032 China

The efficient synthesis of N-（diphenylmethylene） glycine alkyl esters was achieved for the first microwave irradiation under solvent-free condition, using PEG or quaternary ammonium salts as phase transfer catalysts （PTCs）. Under the optimum conditions, N-（diphenylmethylene） glycine alkyl esters were obtained in excellent yields in most cases.

关键词： Microwave Solvent-free N-(Diphenylmethylene)glycine alkyl esters

A Calculation of Electron Impact for the 3d5/2→2p3/2 Line Emission of Fe^(23+)

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Chinese Physics Letters 2000年第6期17卷 403-404页

作者： CHEN Chong-Yang QI Jing-Bo WANG Yan-Sen XU Xue-Ji sun yong-sheng Institute of Modern Physics Fudan UniversityShanghai 200433 Institute of Electric Light Sources Fudan UniversityShanghai 200433 Institute of Applied Physics and Computational Mathematics Beijing 100088

By using the semi-relativistic distorted-wave Born exchange method,electron impact cross sections for the Fe^(23+)line emission 3_(d5/2)→2_(p3/2)are *** calculation involves line formation by direct electron-impact excitation,radiative cascade,resonant excitation,and dielectronic recombination satellites with captured electron in the n≥5 *** results show a good agreement with the recent measurements.

关键词： excitation Electron resonant

OPTIMAL INTERPOLATION ON A CONVO-LUTION CLASS OF FUNCTIONS

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Chinese Science Bulletin 1989年第14期34卷 1148-1152页

作者：孙永生 Beijing Normal university

Ⅰ. PROBLEM AND MAIN RESULTS Let G（t） be a continuous function defined on R. It is said to be a PF density,if integral from n=-∞ to +∞ G（t）dt=1, and is totally positive on R, i.e. （?）n≥1, t1n, τ1n, it holds ... 详细信息

关键词： optimal interpolation convolution class PF density

Siderite pyrolysis in suspension roasting:An in-situ study on kinetics,phase transformation,and product properties

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Journal of Central South University 2022年第6期29卷 1749-1760页

作者： ZHANG Qi sun yong-sheng QIN yong-hong GAO Peng YUAN Shuai School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China National-local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang 110819China

Siderite,as an abundant iron ore,has not been effectively utilized,with a low utilization *** this study,the in-situ kinetics and mechanism of siderite during suspension magnetization roasting(SMR)were investigated to improve the selective conversion of siderite to magnetite and CO,enriching the theoretical system of green SMR using siderite as a *** to the gas products analyses,the peak value of the reaction rate increased with increasing temperature,and its curves presented the feature of an early peak and long *** mechanism function of the siderite pyrolysis was the contraction sphere model(R_(3)):f(α)=3(1−α)2/3;E_(α)was 46.4653 kJ/mol;A was 0.5938 s^(−1);the kinetics equation was k=0.5938exp[−46.4653/(RT)].The in-situ HT-XRD results indicated that siderite was converted into magnetite and wüstite that exhibited a good crystallinity in SMR under a N_(2) *** 620℃,the saturation magnetization(M_(s)),remanence magnetization(Mr),and coercivity(Hc)of the product peaked at 53.63×10^(-3)A·m^(2)/g,10.23×10^(-3)A·m^(2)/g,and 12.40×10^(3)A/m,***,the initial particles with a smooth surface were transformed into particles with a porous and loose structure in the roasting process,which would contribute to reducing the grinding cost.

关键词： siderite suspension magnetization roasting reaction kinetics phase transformation magnetic transition microstructure evolution

Effect of intestinal ischemia-reperfusion on expressions of endogenous basic fibroblast growth factor and transforming growth factor β in lung and its relation with lung repair

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World Journal of Gastroenterology 2000年第3期6卷 353-355页

作者： Xiao Bing Fu Yin Hui Yang Tong Zhu sun Xiao Man Gu Li Xian Jiang Xiao Oing sun Zhi yong sheng Research Laboratory,304th Hospital of PLA,Beijing 100037,China Research Laboratory 304th Hospital of PLA Beijing 100037 China

AIM To study the changes of endogenoustransforming growth factor β(TGFβ)and basicfibroblast growth factor(bFGF)in lung followingintestinal ischemia and reperfusion injury andtheir effects on lung injury and *** Sixty Wistar rats were divided intofive groups,which underwent sham-operation,ischemia(45 minutes),and reperfusion(6,24and 48 hours,respectively)after ischemia(45minutes).Immunohistochemical method wasused to observe the localization and amounts ofboth growth *** Positive signals of both growthfactors could be found in normal lung,mainly inalveolar cells and endothelial cells of *** and reperfusion insult,expressions ofboth growth factors were increased and theiramounts at 6 hours were larger than those ofnormal control or of 24 and 48 hours after *** The endogenous bFGF and TGF βexpression appears to be up-regulated in thelung following intestinal ischemia andreperfusion,suggesting that both growth factorsmay be involved in the process of lung injury andrepair.

关键词： lung intestinal ischemiareperfusion injury basic fibroblast growth factor transforming growth factor p

Opacity of Shock-Generated Argon Plasmas

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Chinese Physics Letters 2001年第7期18卷 921-923页

作者： WANG Fan-Hou CHEN Jing-Ping MENG Xu-Jun ZHOU Xian-Ming LI Xi-Jun sun yong-sheng JING Fu-Qian Laboratory for Shock Wave and Detonation Physics Research Southwest Institute of Fluid PhysicsMianyang 621900 Beijing Institute of Applied Physics and Computational Mathematics Beijing 100088 Institute of Modern Physics Southwest Jiaotong UniversityChengdu 610031

Argon plasmas with uniform density and temperature are generated by a planar shock wave through argon *** opacities of argon plasma,covering the thermodynamic states at temperature of 1.4-2.2eV and in density of 0.0083-0.015g/cm^(3),are investigated by measuring the emitted radiance versus time at several visible *** of the measured opacities with the calculated ones demonstrates that the average atom model can be used well to describe the essential transport behaviour of photons in argon plasma under the above-mentioned thermodynamic condition.A simplified and self-consistent method to deduce the reflectivity R(λ)at the baseplate surface is *** demonstrates that the values of R(λ)are all around 0.4 in the experiments,which are basically in agreement with those given by Erskine previously(1994 *** 5197.)

关键词： thermodynamic mentioned simplified

Effect of temperature on suspension magnetization roasting of hematite using biomass waste as reductant:A perspective of gas evolution

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Journal of Central South University 2024年第6期31卷 1870-1887页

作者： CAO Yue sun yong-sheng HAN Yue-xin GAO Peng LI Yan-jun School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China National-local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang 110819China

The magnetization reduction of hematite using biomass waste can effectively utilize waste and reduce CO_(2) emission to achieve the goals of carbon peaking and carbon *** effects of temperatures on suspension magnetization roasting of hematite using biomass waste for evolved gases have been investigated using TG-FTIR,Py-GC/MS and gas composition *** mixture reduction process is divided into four *** the temperature range of 200-450℃ for mixture,the release of CO_(2),acids,and ketones is dominated in gases *** yield and concentration of small molecules reducing gases increase when the temperature increases from 450 to 900℃.At 700℃,the volume concentrations of CO,H_(2) and CH_(4) peak at 8.91%,8.90% and 4.91%,*** the suspension magnetization roasting process,an optimal iron concentrate with an iron grade of 70.86%,a recovery of 98.66% and a magnetic conversion of 45.70% is obtained at 700℃.Therefore,the magnetization reduction could react greatly in the temperature range of 600 to 700℃ owing to the suitable reducing *** study shows a detail gaseous evolution of roasting temperature and provides a new insight for studying the reduction process of hematite using biomass waste.

关键词： suspension magnetization roasting biomass pyrolysis gases evolution reduction behavior

Mechanism of microwave assisted suspension magnetization roasting of oolitic hematite ore

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Journal of Central South University 2022年第2期29卷 420-432页

作者： ZHOU Wen-tao sun yong-sheng HAN Yue-xin GAO Peng LI Yan-jun College of Chemical and Biological Engineering Shandong University of Science and TechnologyQingdao 266590China School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China National-local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

Oolitic hematite is an iron ore resource with rich reserves,complex composition,low grade,fine disseminated particle sizes,and a unique oolitic *** this study,a microwave-assisted suspension magnetization roasting technology was proposed to recover and utilize the *** results showed that under the conditions of microwave pretreatment temperature of 1050℃ for 2 min,a magnetic concentrate with an iron grade of 58.72%at a recovery of 89.32%was obtained by microwave suspension magnetization roasting and magnetic ***,compared with the no microwave pretreatment case,the iron grade and recovery increased by 3.17%and 1.58%,*** pretreatment increased the saturation magnetization of the roasted products from 24.974 to 39.236(A∙m^(2))/kg and the saturation susceptibility from 0.179×10^(−3) m^(3)/kg to 0.283×10^(−3) m^(3)/*** were formed between the iron and gangue minerals,and they gradually extended to the core of oolite with the increase in the pretreatment *** reducing gas diffused from outside to inside along the microcracks,which promoted the selective transformation of the weak magnetic hematite into the strong magnetic magnetite.

关键词： oolitic hematite microwave suspension magnetization roasting phase and magnetic transformation microstructure evolution

西方翻译研究的文化取向、文化初识与文化转向

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外语学刊 2010年第4期 135-138页

作者：孙圣勇广东水利电力职业技术学院广州510635 武汉大学武汉430072

据文字记载,西方翻译实践和理论研究历时已愈两千多年。文章梳理西方古代、现代、当代译者的翻译实践和理论,得出结论:西方古代译语文化取向的意译同化翻译策略一直是主流。西方现代翻译理论以尤金·奈达(Eugene ***)的交际学翻译理论... 详细信息

据文字记载,西方翻译实践和理论研究历时已愈两千多年。文章梳理西方古代、现代、当代译者的翻译实践和理论,得出结论:西方古代译语文化取向的意译同化翻译策略一直是主流。西方现代翻译理论以尤金·奈达(Eugene ***)的交际学翻译理论和社会符号学翻译理论为代表,奈达的动态对等翻译思想的着眼点是消除语言和文化之间的差异,以适应译语读者。文章对近二三十年西方从文化角度研究翻译这一热点进行研究,结果发现西方文化翻译理论研究转向的理论标识是操控学派翻译理论、多元系统论翻译理论、描写学派翻译理论、解构主义翻译理论、后殖民主义翻译理论和女性(权)主义翻译理论等,导致风靡西方翻译理论界的翻译研究文化转向的真正原因是翻译学研究与文化学研究同时兴起的合力所致。

关键词：西方翻译文化取向差异初识文化转向