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Bifunctional two-carbon reagent made from acetylene via 1,2-difunctionalization and its applications

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Science china Chemistry 2024年第3期67卷 936-944页

作者： Bo yang Kangkui Li Yongdong Wang Shifa zhu Key Laboratory of Functional Molecular Engineering of Guangdong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China school of Chemistry and Chemical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Singfar Laboratories Guangzhou 510670China

There are very limited approaches to directly gluing two molecules for the production of internal alkenes using the vastly abundant acetylene via 1,2-difunctionalization. Conversion of gaseous acetylene to internal alkenes via 1,2-difunctionalization in a desired manner is not as easy as it might be expected due to the potential competition reactions between acetylene and alkene produced and the difficulty in handling this harmful reagent and controlling the regio-and stereoselectivity. In this work, we designed an efficient catalytic system for the incorporation of acetylene gas into tremendous(E)-β-bromo vinylsulfones, which are bench-stable, easy to operate, and can function as bifunctional acetylene and show a rich reactivity profile in Sonogashira coupling, Heck coupling, substituted reaction, and various desulfonylation transformations, providing numerous internal alkenes.

关键词： acetylene 1 2-difunctionalization photocatalysis vinylsulfone

Effects of Temperature and [S] on the Kinetics of Nitrogen Removal from Liquid Steel

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Journal of Materials Science & technology 2001年第2期17卷 233-236页

作者： Jie FU, Shixiang ZHOU, Ping WANG, Lin DI and Jian zhu Metallurgy school, university of Science and {3. beijing, beijing 100083. china Sch. of Met. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The kinetics of denitrogenation from liquid steel was studied by using an oxygen-nitrogen analysis system(LECO TC-43.) under 1600 degreesC similar to 2813.degreesC conditions. The results show that when [S]=0.005%, nitrogen removal was controlled by nitrogen transfer in liquid diffusion layer, when [S]=0.012% and 0.140%, it was controlled by both nitrogen transfer in liquid diffusion layer and the chemical reaction at the liquid-gas interface below 2250 degreesC, and by nitrogen transfer in liquid diffusion layer under 2250 degreesC similar to 2813.degreesC conditions. The activation energy E-a was 57 kJ/mol for 0.0050%[S], 95 kJ/mol for 0.012%[S], 165 kJ/mol for 0.140%[S]. The resistance of sulphur on nitrogen removal decreased with the temperature rose, and disappeared at 263. degreesC. Based on the results obtained, it has been answered why the nitrogen in liquid steel can be decreased rapidly by carbon-oxygen reaction under very high oxygen and sulphur content conditions during the BOF, EAF, VOD and AOD steelmaking processes.

关键词： Effects of Temperature and on the Kinetics of Nitrogen Removal from Liquid Steel

Sticking-up Behaviors and Surface Friction of IF Electrogalvanized Sheet Steel in Forming

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 61-63,68页

作者： Jiming Hu Jixun Wu Yanping Lu Yanrong zhu (Material Science and Engineering school, university of Science and {3. beijing, beijing 100083. china) Univ of Science and technology Beijing Beijing China

X-ray diffraction (XRD), ball-disc friction and wearing machine and draw-bead test were introduced to investigat the strcusture and workability of IF sheet steel electrogalvanized deposits prepared from sulphate solution system. It was shown that the picking-up of the zinc coating on die strengthened with the increasing of friction factor which was originally affected by the coating's structure. Duing forming, (00X) planes (X= 2, 4) preferential orientation of zinc deposits increased, which resulted in enhanc ing the coating's friction behaviors. Therefore, the forming mechanism of electrogalvedzed deposit was demonstrated that both friction and the stricking -up behaviors of the coating are intensified simultaneously and affect each other.

关键词： electrogalvanized deposit forming friction factor

Development of a New Subermerged Entry Nozzle in Thin Slab Caster

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 183-186页

作者： Yanping Bao Jianqiang zhu Wei Jiang Naiyuan Tian Baomei Xu(Metallurgy school, university of Science & {3. beijing, beijing 100083. china) Metallurgy school University of Science and Technology Beijing Beijing 100083 China

The fluid flow in the mould of the thin slab continuous caster has a large intluence on the quality of slabs and its *** fluid flow pattern can be controlled by the SEN (Submerged Entry Nozzle) structure. Traditional SEN can not decrease the surface turbulence and penetration depth at the same time, especially at high casting speed. In order to improve the fluid flow in the mould, a new structure SEN-Dissipation SEN have been invented. The water modeling experiments proved that the dissipation SEN could satisfy, the needs of fluid flow condition in the mould at high casting speed.

关键词： thin slab caster mould dissipation submerged entry nozzle water-model

Prediction for RNA planar pseudoknots

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Progress in Natural Science:Materials International 2007年第6期17卷 717-724页

作者： Li Hengwu1,2, zhu Daming1, Liu Zhendong1 and Li Hong2(1. school of computer Science and {3., Shandong university, Jinan 250100, china 2. Department of computer, Shandong Economic university, Jinan 250014, china) school of computer Science and technology Shandong University Jinan 250100 China Department of computer Shandong Economic University Jinan 250014 China

Based on m-stems and semi-extensible structure, a model is presented to represent RNA planar pseudoknots, and corresponding dynamic programming algorithm is designed and implemented to predict arbitrary planar pseudoknots and simple non-planar pseudoknots with O(n4) time and O(n3. space. The algorithm folds total 245 sequences in the Pseudobase database, and the test results indicate that the algorithm has good accuracy, sensitivity and specificity.

关键词： algorithm RNA secondary structure pseudoknot dynamic programming.

A constitutive model of frozen soil with damage and numerical simulation for the coupled problem

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 699-711页

作者： zhu ZhiWu, NING JianGuo& MA Wei 1 school of Mechanics and Engineering, Southwest Jiaotong university, Chengdu 61003.,{3. 2 State Key Laboratory of Explosion Science and technology, beijing Institute of technology, beijing 100081,{3. 3.Key Laboratory of Frozen Soil Engineering, CAREERI, CAS, Lanzhou 73.000,{3. school of Mechanics and Engineering Southwest Jiaotong University Chengdu China State Key Laboratory of Explosion Science and technology Beijing Institute of Technology Beijing China Key Laboratory of Frozen Soil Engineering CAREERI CAS Lanzhou China

Based on the microcosmic mechanics of composite materials, an elastic constitutive model for frozen soil with damage is presented. For frozen sandy soil with a range of ice contents and under a range of temperature conditions, quantitative results determined by this constitutive model agree with practically measured stress-strain curves. After numerically simulating the coupled water, temperature and stress fields of channel frozen and frozen roadbed using a self-developed finite-element routine, more accurate and practical calculation results for the temperature field coupled with stress, displacement and strain fields are obtained; the results match predictions and tests undertaken by earlier researchers. Our results support the reliability of our routine for calculating interdependent physical quantities of frozen soil and for describing the relationships between them. Our program can offer necessary constraints for engineering design and construction in permafrost regions.

关键词： frozen soil microcosmic mechanics roadbed coupling stress field

Force Parameter Model of 3.Roll Mills for Continuous Cold Rolling Wires

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International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 292-295页

作者： Baolong Zheng1 Li Sun2 Ruichen An2 Jin Wang1 Weichang zhu1(l Material Science and Engineering school, university of Science and {3. beijing, beijing 100083. china2 Tangshan iron and Steel Co. Ltd., Tangshan 063.00, china) Material Science and Engineering school University of Science and Technology Beijing Beijing 100083 China Tangshan Iron and Steel Co. Ltd. Tangshan 063000 China

Based on experimental data, the mathematical model of rolling force parameters of 3.roll mills was studied. The structure ofthe model was theoretically set up and the coefficients were determined by static analysis of the data. The torque in continuous rollingwas measured, and the characteristics and efficiency of 3.roll mills are investigated.

关键词： 3.roll mill force mathematical model cold rolling wire

A highly selective electrochemical impedimetric sensor for imidacloprid determination based on WO_(3./MoS_(2)nanosheets/molecularly imprinted polymer composite

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Rare Metals 2024年第3期43卷 1309-1315页

作者： Long-Hua Ding Ya-wen Wang Qiu-wen Li Li-Li Zhang Ai-zhu Wang Institute for Advanced Interdisciplinary Research School of Chemistry and Chemical EngineeringUniversity of JinanJinan250022China HCA Florida Healthcare Westside/Northwest Hospital Internal Medicine PlantationFL33324USA

In this study,an electrochemical impedimetric sensor was established for imidacloprid(IMI)detection based on WO_(3./MoS_(2)and molecular imprinted polymer(MIP)*** layer was prepared on electrode surface by electropolymerization of o-phenylenediamine(o-PD)in the presence of IMI template,which ensured the specific rec-ognization toward IMI.

关键词： electrochemical polymer polymerization

Recognition of Gene Acceptor Site Based on Multi-objective Optimization

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Acta Biochimica et Biophysica Sinica 2005年第7期37卷 435-439页

作者： Jing ZHAO~(1,3.4) Yue-Min zhu~2 Pei-Ming SONG~1 Qing FANG~1 Jian-Hua LUO~(1,3. 1 school of Life Science & technology,Shanghai Jiaotong {3.,Shanghai 200240,china 2 CREATIS,CNRS UMR 5515,INSA Lyon,69621 Villeurbanne Cedex,France 3.Shanghai Center for Bioinformation and technology,Shanghai 20023.,china 4 Logistical Engineering {3.,Chongqing 400016,china school of Life Science & technology Shanghai Jiaotong UniversityShanghai 200240 China Shanghai Center for Bioinformation and technologyShanghai 20023. China Logistical Engineering universityChongqing 400016 China CREATIS CNRS UMR 5515 INSA Lyon69621 Villeurbanne Cedex France

A new method for predicting the gene acceptor site based on multi-objective optimization isintroduced in this *** models for the acceptor,branch and distance between acceptor site andbranch site were constructed according to the characteristics of the sequences from the exon-intron databaseand using common biological *** acceptor function,branch function and distance functionwere defined respectively,and the multi-objective optimization model was constructed to recognize thesplice *** test results show that the algorithm used in this study performs better than the SplicePredictor,which is one of the leading acceptor site detectors.

关键词： multi-objective optimization acceptor site recognition