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Effect of surface layer softening from previous electrochemical corrosion on electrochemical cold drawing of Q235 steel bar

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journal of Iron and Steel Research International 2022年第5期29卷 819-835页

作者： j.L.Guo T.j.chen State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou730050GansuChina

The effects of H_(2)SO_(4)concentration and current in electrochemical corrosion on surface layer softening or plasticizing of Q235 steel bar and their effects on subsequent electrochemical cold drawing(ECD)were *** results indicate that the electrochemical corrosion can soften or plasticize the surface layer of Q235 steel bar and then make the subsequent ECD be conducted more *** softening degree and thickness of the surface layer are continuously enhanced with increasing corrosion rate,i.e.,increasing H_(2)SO_(4)concentration or current,due to the generation of more vacancy clusters in deeper regions of surface *** vacancy clusters then relax dislocations through being absorbed during ECD,and the formation and movement of additional dislocation flux are thereby enhanced,resulting in the further obvious decrease in the drawing *** is also due to the enhanced formation and movement of additional dislocation flux that the dislocation density and thus the hardness of the surface layer are decreased,as well as that the texture structure is *** behaviors are enhanced as the corrosion rate increases.

关键词： Electrochemical corrosion Electrochemical cold drawing Surface layer softening Vacancy Additional dislocation flux

Addition of polyfluoropolyhaloethanes to alkenes

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Chinese journal of Chemistry 1995年第3期13卷 273-279页

作者： chen, j HU, CM CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSHANGHAI 200032PEOPLES R CHINA

In the presence of CrCl3/Fe redox system, polyfluoropolyhaloethanes readily added to electron-deficient or electron-rich alkenes, giving the corresponding 1:1 hydropolyfluoroalkylation product or 1:1 adduct in high yields. This reaction provided a simple and convenient method to synthesize building blocks containing a CF3 or CF2 moiety.

关键词： CRCL3/FE REDOX SYSTEM POLYFLUOROPOLYHALOETHANE ALKENE ADDITION ADDUCT

Direct synthesis of per(poly)fluoroalkylmethyl-substituted electrophilic cyclopropane derivatives

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Chinese journal of Chemistry 1995年第4期13卷 368-379页

作者： chen, j HU, CM CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSHANGHAI 200032PEOPLES R CHINA

A convenient and direct per(poly)fluoroalkylmethyl-introducing cyclopropanation reaction was described. In the presence of CrCl3/Fe, per(poly)fluoroalkyl iodides reacted with diethyl allylmalonate and its analogs to give per(poly)fluoroalkylmethyl-substituted electrophilic cyclopropane derivatives in high yields. This reaction was considered to proceed by two steps: radical addition followed by cyclopropanation.

关键词： FLUOROALKYL IODIDE DIETHYL ALLYLMALONATE CRCL3/FE REDOX SYSTEM ADDITION CYCLOPROPANATION

Gas Line Pressure Fluctuation Analysis of a Gas-Liquid Reactor

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journal of Thermal Science 2005年第3期14卷 267-271页

作者： j.j.j. chen j.C. ZHAO Chemical & Materials Engineering Department The University of Auckland Private Bag 92019 Auckland New Zealand ProfessorChemical & Materials Engineering Department The University of Auckland Private Bag 92019 Auckland New Zealand

To ensure efficient operation of metallurgical gas-liquid reactors, the gas bubbles must be uniformly distributed. For high temperature metallurgical reactors, it is impractical and unsafe to carry out visual observations. An air-water model was used to study the relationship between the bubble flow patterns and the pressure fluctuation signals. The fluctuation signals captured in the time domain were transformed into the frequency domain. Various parameters obtained from the transformed data were analysed for their suitability for delineating the bubble flow patterns observed. These parameters and the flow patterns were found to be well-correlated using the gas flow number.

关键词： gas liquid reactors bubble distribution signal analysis

A modified multi-objective particle swarm optimization approach and its application to the design of a deepwater composite riser

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Acta Mechanica Sinica 2018年第2期34卷 275-284页

作者： Y.Zheng j.chen Department of Mechanics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory for Engineering Structural Analysis and Safety Assessment Wuhan 430074China

A modified multi-objective particle swarm optimization method is proposed for obtaining Pareto-optimal solutions effectively. Different from traditional multiobjective particle swarm optimization methods, Kriging meta-models and the trapezoid index are introduced and integrated with the traditional one. Kriging meta-models are built to match expensive or black-box functions. By applying Kriging meta-models, function evaluation numbers are decreased and the boundary Pareto-optimal solutions are identified rapidly. For bi-objective optimization problems, the trapezoid index is calculated as the sum of the trapezoid’s area formed by the Pareto-optimal solutions and one objective axis. It can serve as a measure whether the Pareto-optimal solutions converge to the Pareto front. Illustrative examples indicate that to obtain Paretooptimal solutions, the method proposed needs fewer function evaluations than the traditional multi-objective particle swarm optimization method and the non-dominated sorting genetic algorithm II method, and both the accuracy and the computational efficiency are improved. The proposed method is also applied to the design of a deepwater composite riser example in which the structural performances are calculated by numerical analysis. The design aim was to enhance the tension strength and minimize the cost. Under the buckling constraint, the optimal trade-off of tensile strength and material volume is obtained. The results demonstrated that the proposed method can effec tively deal with multi-objective optimizations with black-box functions.

关键词： Multi-objective particle swarm optimization Kriging meta-model Trapezoid index Deepwater composite riser

青藏高原及其周边泥盆纪综合地层、生物群与古地理演化

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中国科学：地球科学 2024年第4期54卷 1058-1090页

作者：郄文昆梁昆郭文高彪宋俊俊陈波黄璞乔丽徐洪河陈吉涛孙语聪张以春中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室南京210008 中国科学院大学南京学院南京211135

青藏高原及其周边泥盆系分布广泛、类型多样、化石丰富,记录着北半球古亚洲洋的持续消减和南半球原特提斯洋向古特提斯洋转变的关键过程,对阐明这一时期的全球古地理格局、板块运动和生物多样性变化具有重要意义.南天山(洋)缝合带和龙木... 详细信息

青藏高原及其周边泥盆系分布广泛、类型多样、化石丰富,记录着北半球古亚洲洋的持续消减和南半球原特提斯洋向古特提斯洋转变的关键过程,对阐明这一时期的全球古地理格局、板块运动和生物多样性变化具有重要意义.南天山(洋)缝合带和龙木错-双湖-昌宁-孟连(洋)缝合带两侧的地块分属不同沉积体系和生物古地理区系,指示该洋盆具有显著的构造古地理分隔意义,分别代表了古亚洲洋和古特提斯洋的主支洋盆,以此为界泥盆系可以划分为天山型、特提斯型和冈瓦纳型三种类型.本文主要基于近年来青藏高原及其邻区泥盆纪地层古生物的研究进展,分别提供最新的综合地层格架,并结合沉积物源分析和生物群特征对比进行古地理重建,为探讨青藏高原及其邻区各个块体的早期地质演化及其动力学机制奠定基础.基于碎屑锆石物源分析和生物古地理研究,特提斯喜马拉雅带、保山地块、南羌塘地块、北羌塘地块、思茅地块、腾冲地块和华南板块沉积物源与印度板块具有亲缘性,而拉萨地块与澳大利亚板块具有亲缘性,且可能位于华南板块与澳大利亚板块之间.早泥盆世埃姆斯期,华南板块可能已经从冈瓦纳大陆北缘裂解出来,代表着金沙江-哀牢山洋的打开.中泥盆世,古特提斯洋洋中脊快速扩张,对应着全球海平面上升、碳酸盐岩台地的广泛分布和泥盆纪海水锶同位素的最低值.晚泥盆世古特提斯洋已达到相当规模,最终导致古特提斯缝合带中晚泥盆世放射虫硅质岩大量产出.

关键词：泥盆系古特提斯洋综合地层生物群物源分析古地理

Methylation status of p16 gene in colorectal carcinoma and normal colonic mucosa

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World journal of Gastroenterology 1999年第5期5卷 451-454页

作者： Zhang j Lai MD chen j Hangzhou Railway Cent Hosp Dept Clin Pathol Hangzhou 310000 Zhejiang Provin Peoples R China Zhejiang Univ Sch Med Dept Pathol Hangzhou 310006 Zhejiang Provin Peoples R China

INTRODUCTIONp16 gene (also known as MTS-1, INK4a, CDKN2A), located on chromosome 9p21, is a G1-specific cell-cycle regulatory gene. It is composed of three exons, which encode 156 amino acids[1]. The gene is frequently inactivated in many human cancers. Unlike other tumor-suppressor genes that are commonly inactivated by point mutations, small homozygous deletions and methylation of the promoter represent the major mechanism of p16 gene inactivation[2,3]. In the Western countries, colorectal carcinoma ranks first among malignant tumors. The mortality from colorectal carcinoma has been rapidly growing in China in the last two to three decades. The genetic alterations involved in this tumor are still unclear. Rare mutation and infrequent deletion of p16 gene in primary colorectal carcinoma has been widely reported[4]. There were a few papers on p16 gene methylation in colorectal carcinoma, but the results were contradictory[5,6]. In this study, we have examined a total of 60 samples of colorectal carcinoma and paired 60 samples of the normal colonic mucosa for methylation by means of PCR-based methylation assay. There is infrequent methylation in the promoter of p16 gene both in colorectal carcinoma and normal colonic mucosa. The methylation status in 5′ CpG island of p16 gene in colorectal carcinoma is not related to the clinical pathologic parameters of these tumors.

关键词： Colonic mucosa colorectal neoplasms p16 gene methylation

INTERFACIAL DEBONDING OF FRC UNDER CYCLIC LOADING

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Acta Metallurgica Sinica(English Letters) 2004年第3期17卷 327-330页

作者： Q.j.Zhu Y.H.chen j.chen Department of Civil Engineering Hebei Institute of Technology Tangshan 063009 China School of Civil Engineering Beijing Jiaotong University Beijing 100044 ChinaDepartment of Civil Engineering Hebei Institute of Technology Tangshan 063009 China

With the increasingly use of FRC (fiber-reinforced composite) in urban lifelines, me-chanical properties investigation is very important for disaster resistance, especiallythe investigation of fatigue properties. Based on the shear-lag model, an usual com-posite model under cyclic loading is established. According to the Paris formula, therelationship between interfacial fatigue parameters and the number of cycles is ob-tained under the cyclic loading. Interfocial fatigue properties of this model and thegrowth of the interfacial fatigue crack are analyzed. And the Poisson ratio is consid-ered also.

关键词： interfacial debonding fiber matrix cyclic loading crack growth

Ground-state mass of ^(22)Al and test of state-of-the-art ab initio calculations

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Chinese Physics C 2024年第3期48卷 72-78页

作者：孙铭泽于越王新鹏王猛李健国张玉虎 K.Blaum 陈祖毅陈瑞九邓涵宇付超义葛文文黄文嘉焦红扬李红蕙李宏福罗胤芳廖挺 YuALitvinov 司敏帅鹏史金阳王茜邢元明徐星徐瑚珊许甫荣袁琪 T.Yamaguchi 颜鑫亮杨建成原有进周小红周旭张敏曾奇 CAS Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Max-Planck-Institut für Kernphysik Saupfercheckweg 169117 HeidelbergGermany GSI Helmholtzzentrum für Schwerionenforschung Planckstraße 164291 DarmstadtGermany Advanced Energy Science and Technology Guangdong Laboratory Huizhou516007China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Department of Physics Saitama UniversitySaitama 338-8570Japan School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

The ground-state mass excess of the T_(z)=−2 drip-line nucleus ^(22)Al is measured for the first time as 18103(10)keV using the newly-developed Bρ-defined isochronous mass spectrometry method at the cooler storage ring in *** new mass excess value allowed us to determine the excitation energies of the two low-lying 1+states in ^(22)Al with significantly reduced uncertainties of 51 *** compared to the analogue states in its mirror nucleus ^(22)F,the mirror energy differences of the two 1^(+)states in the ^(22)Al-^(22)F mirror pair are determined to be−625(51)keV and−330(51)*** excitation energies and mirror energy differences are used to test the state-of-the-art ab initio valence-space in-medium similarity renormalization group calculations with four sets of interactions derived from the chiral effective field *** mechanism leading to the large mirror energy differences is investigated and attributed to the occupation of theπs_(1/2) orbital.

关键词： nuclear mass Bρ-defined IMS mirror energy difference ab initio VS-IMSRG calculations chiral interactions