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A 3-D Differential Method for Solving Rolling Force of PC Hot Strip Mill

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Journal of Iron and Steel Research International 2010年第9期17卷 36-39页

作者： WANG xue-song PENG Yan XU Li-pu LIU Hong-min State Key Laboratory of Metastable Materials Science and Technology Engineering Research Center of Rolling Equipment and Complete Technology of Ministry of Education Yanshan University Qinhuangdao 066004 Hebei China

The character of the deformation zone on pair cross rolls is different from that of the regular 4-high mill. Considering comprehensive influences of normal stress and shear stress in rolling direction, width direction and thickness direction, the rolling force calculation model of the PC （pair crossed） hot strip mill is built. Taking the entry stress and the exit stress of strip as the boundary conditions, the longitudinal and transverse distribution of rolling force is worked out by the differential method. Then the total rolling force is calculated, and calculated results are verified by experimental data.

关键词： PC rolling mill rolling force differential method model building

Absorption Complex between Porphyrin and Phenothiazine in Reverse Micelles

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Chinese Chemical Letters 2002年第10期13卷 1007-1010页

作者： Jun Hua YU xue song WANG Bao Wen ZHANG Yi CAO Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing 100101

The interaction between amphiphilic porphyrin and phenothiazine in AOT/isooctane/water reverse micelle was investigated by UV-Vis spectra. A new absorption complex between the two species is formed in such circumstances, which is ascribed to the enrichment of the components by the reverse micelle. The fluorescence quenching of CHTTP by PTH becomes more efficient after the formation of the absorption complex.

关键词： Porphyrin phenothiazine absorption complex reverse micelle.

Brazing 6061 aluminum alloy with Al-Si-Zn filler metals containing Sr

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International Journal of Minerals,Metallurgy and Materials 2013年第4期20卷 365-370页

作者： Wei Dai song-bai xue Feng Ji Jiang Lou Bo Sun Shui-qing Wang School of Materials Science and Technology Nanjing University of Aeronautics and Astronautics Zhejiang Xinrui Welding Material Co. Ltd

Al-6.5Si-42Zn and Al-6.5Si-42Zn-0.09Sr filler metals were used for brazing 6061 aluminum alloy. Air cooling and water cooling were applied after brazing. Si phase morphologies in the brazing alloy and the brazed joints were investigated. It was found that zinc in the Al-Si filler metals could reduce the formation of eutectic Al-Si phase and lower the brazing temperature at about 520℃. Adding 0.09wt% Sr element into the Al-6.5Si-42Zn alloy caused a-Al phase refinement and transformed acicular Si phase into the finely fiber-like. After water cooling, Zn element dissolved into the Al-Si eutectic area, and η-Zn phase disappeared in the brazed joints. Tensile strength testing results showed that the Sr-modified filler metal could enhance the strength of the brazed joints by 13% than Al-12Si, while water-cooling further improved the strength at 144 MPa.

关键词： aluminum alloys brazing joints filler metals cooling strontium

Left bundle branch pacing in a ventricular pacing dependent patient with heart failure:A case report

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World Journal of Clinical Cases 2022年第20期10卷 7090-7096页

作者： Bing-xue song Xia-Xia Wang Yi An Ying-Ying Zhang Department of Cardiology The Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina

BACKGROUND Left bundle branch pacing(LBBP)is a physiological pacing method that has emerged in recent *** is an ideal choice for patients with complete left bundle branch block who are in need of cardiac resynchronization therapy(CRT).Moreover,LBBP is superior in maintaining physiological ventricular activation and can effectively improve heart function and quality of life in patients with pacemaker-induced ***,LBBP in pacing-dependent patients who already have cardiac dysfunction has not been well *** SUMMARY A 69-year-old male patient presented with symptoms of chest tightness,palpitation and systolic heart failure with New York Heart Association class III for 1 *** 12-lead electrocardiogram showed atrial fibrillation with third-degree atrioventricular block and ventricular premature *** revealed a right bundle branch block,atrial fibrillation with third-degree atrioventricular block,frequent multifocal ventricular premature beats,Ron-T and ventricular *** echocardiogram documented an enlarged left atrium and left ventricle and a low left ventricular ejection *** angiography indicated a stenosis of 30%in the middle left anterior descending ***,a CRT-D pacemaker was the best choice for this patient according to previous ***,the patient was worried about the financial burden.A single-chamber pacemaker with LBBP was selected,with the plan to take amiodarone and upgrade with dual-chamber implantable cardioverter-defibrillator or CRT-D at an appropriate *** the follow-up at 3 mo after LBBP,the patient showed an improvement in cardiac function with slight improvement in echocardiography parameters,and the New York Heart Association functional class was maintained at ***,the patient no longer suffered from chest tightness and *** showed decreased ventricular arrhythmia of less than 5%.CONCLUSION LBBP might be used in patients with heart failure

关键词： Left bundle branch area pacing Physiological pacing Heart failure Cardiac resynchronization therapy Pacing-dependent Case report

Purification and Characterization of 2-Haloacid Dehalogenase from Marine Bacterium Paracoccus sp. DEH99, Isolated from Marine Sponge Hymeniacidon perlevis

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Journal of Ocean University of China 2014年第1期13卷 91-96页

作者： ZHANG Jinyou XIN Yanjuan CAO Xupeng xue song ZHANG Wei Marine Bioproducts Engineering Group Dalian Institute of Chemical PhysicsCAS University of Chinese Academy of Sciences Flinders Centre for Marine Bioproducts Development (FCMB2) Medical Biotechnology School of Medicine

2-haloacid dehalogenases constitute a group of dehalogenases which are capable of dehalogenating the halogenated organic compounds. So far, the 2-haloacid dehalogenases have been found in many bacteria, but not in Paracoccus genus. In the present study, one enzyme 2-haloacid dehalogenase(designated as Deh99), induced by DL-2-chloropropionate(DL-2-CPA), was purified from the marine bacterium Paracoccus sp. DEH99, isolated from marine sponge Hymeniacidon perlevis. The enzyme of Deh99 was purified to homogeneity by ammonium sulfate precipitation, ion exchange chromatography(Q-Sepharose HP), and Superdex 200 gel filtration chromatography. The molecular weight of Deh99 was estimated to be 25.0 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE), and 50.0 kDa natively by gel filtration chromatography. The enzyme of Deh99 stereospecifically dehalogenated L-2-CPA to produce D-lactate, with an apparent Michaelis-Menten constant(Km) value of 0.21 mmol L-1 for L-2-CPA. The optimal pH and temperature for Deh99 activity were 10.0 and 40℃, respectively. The enzyme of Deh99 acted on short-carbon-chain 2-haloacids, with the highest activity towards monochloroacetate. The activity of Deh99 was slightly affected by DTT and EDTA, but strongly inhibited by Cu2+ and Zn2+. The enzyme of Deh99 shows unique substrate specificity and inhibitor sensitivities compared to previously characterized 2-haloacid dehalogenases and is the reported one about purified 2-haloacid dehalogenase isolated from the bacteria of Paracoccus genus.

关键词： Paracoccus sp 2-Haloacid dehalogenase purification marine bacterium marine sponge

Quantification of the Activation Capabilities of Lewis/Brφnsted Acid for Electrophilic Trifluoromethylthiolating Reagents

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Chinese Journal of Chemistry 2020年第2期38卷 130-134页

作者： Huiying Kang Biying Zhou Man Li Xiao-song xue Jin-Pei Cheng State Key Laboratory of Elemento-Organic Chemistry Collaborative Innovation Center of Chemical Science and EngineeringNankai UniversityTianjin 300071China Center of Basic Molecular Science Department of ChemistryTsinghua UniversityBeijing 100084China

Summary of main observation and conclusion Electrophilic trifluoromethylthiolation has emerged as an important and efficient methodology for installing the SCF3 moiety onto an array of organic *** to the low reactivities of trifluoromethylthiolating reagents,these transformations often require activation through an exogenous Lewis/Br0nsted *** report herein the quantification of the activation capabilities of Lewis/Br0nsted acids for trifluoromethylthiolating reagents through computing the differenee in trifluoromethylthio cation donor ability(Tt+DA)between the"activated"and"unactivated"reagent.A moderate correlation is found to exist between the activation capability and Lewis acidity.

关键词： activation moiety donor

Ratiometric Fluorescent Probe Based on Novel Red-emission BODIPY for Determination of Bovine Serum Albumin

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Chemical Research in Chinese Universities 2014年第5期30卷 738-742页

作者： song Fengling xue Yingying WANG Xu WANG Jingyun XIONG Xiaoqing PENG Xiaojun State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116024 P. R. China

A novel red-emission boron-dipyrromethene（BODIPY） dye with a pyrrole ring was synthesized simply via one-pot reaction. The spectral properties of it were investigated under the conditions of different solvents. The results show that the as-prepared BODIPY dye is extremely sensitive to solvent polarity, and the fluorescent emission enhances with the decrease of solvent polarity. In aqueous buffer, the addition of bovine serum albumin leads to a ratiometric change in absorption spectra with an association constant of 1.16×10^6 L/mol. Meanwhile, the fluorescence emission increases greatly at 622 nm but changes slightly at 575 nm. The response time is very short（less than 3 min）, and the changes of color can be noticed by naked eyes. Bovine serum albumin can be detected by this ratiometric fluorescence probe, but other proteins or enzymes cannot be detected by this method, which indicates that this novel dye has high selectivity towards bovine serum albumin. The reason is that bovine serum albumin has suitable hydro- phobic cavities for binding with the dye. In addition, the dye molecule can penetrate cell membrane easily and make a fast fluorescent stain, which makes it a potential probe for living-cell fluorescence imaging.

关键词： Fluorescent dye Boron-dipyrromethene(BODIPY) Bovine serum albumin Ratiometric High selectivity

High-temperature properties and microstructure of Mo microalloyed ultra-high-strength steel

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International Journal of Minerals,Metallurgy and Materials 2011年第4期18卷 407-412页

作者： Qi-hang Han Yong-lin Kang Xian-meng Zhao Lu-feng Gao xue-song Qiu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

The high-temperature mechanical properties and microstructure of forging billets of C-Si-Mn-Cr and C-Si-Mn-Cr-Mo ultra-high-strength cold-rolled steels（tensile strength≥1000 MPa,elongation≥10%） were *** the comparison of reduction in area and hot deformation resistance at 600-1300°C,the Mo-containing steel was found to possess a higher strength and a better plasticity than the Mo-free *** equilibrium phase diagram and atom fraction of Mo in different phases at different temperatures were calculated by Thermo-Calc software（TCW）.The results analyzed by using transmission electron microscopy and TCW show that precipitates in the Mo-containing steel are primarily M23C6,which promote pearlite *** experimental data also show that a lower ductility point existing in the Mo-free steel at 850°C is eliminated in the Mo-containing *** is mainly due to the segregation of Mo at grain boundaries investigated by electron probe microanalysis（EPMA）,which improves the strength of grain boundaries.

关键词： high strength steels high temperature properties microstructure molybdenum thermodynamics

Carbon-Selective Difluoromethylation of Soft Carbon Nucleophiles with Difluoromethylated Sulfonium Ylide

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Chinese Journal of Chemistry 2018年第11期36卷 1069-1074页

作者： Jiansheng Zhu Hanliang Zheng Xiao-song xue Yisa Xiao Yafei Liu Qilong Shen Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecu- lar Synthesis Shanshai Institute of Organic Chemistry University of Chinese Academy Sciences Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 China State Key Laboratory of Elemento-Organic Chemistry Collaborative Innovation Center of Chemical Science and Engineer Nankai University Tianjin 300072 China

A highly carbon‐selective difluoromethylation of soft carbon nucleophiles including β‐ketoesters, malonates, oxindoles, benzofuranones and ketene silyl acetals with a difluoromethylated sulfonium ylide under mild conditions was described. Mechanistic studies suggest that these difluoromethylating reactions proceed via a difluorocarbene pathway.

关键词： fluorine electrophilic substitution ylides regioselectivity