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Stress and thickness calculation of a bolted flat cover with double metal sealing rings

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Nuclear Science and Techniques 2018年第8期29卷 210-217页

作者： xiao-Yan Wang Shi-feng zhu xiao Wang xiao-Chun Zhang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

The design of a bolted flat cover is extremely important for the structural integrity of pressure *** present design codes provide the thickness calculation equations for a bolted flat cover with single metal ***,the rules for a bolted flat cover with double metal sealing rings are not developed to *** the study,a new thickness calculation equation for the bolted flat cover with double metal sealing rings is ***,the theoretical stress solution for bolted flat cover with the double metal sealing rings is obtained,based on the theory of simply supported circular plate and then verified using the results from finite element *** results indicate that the influence of double metal sealing ring on the stress of the flat cover is more serious compared to single metal ***,a more accurate and reasonable equation is proposed to calculate the thickness of bolted flat cover with double metal sealing rings based on the derived theoretical equations of maximum ***,the influence of linear load and the spacing between rings on the thickness are ***,a few suggestions are provided to design low-pressure or atmosphere pressure *** study provides a theoretical foundation to develop design codes of pressure vessels in nuclear reactors.

关键词：厚度计算扁平金属封面戒指应力和计算方程压力解

Creep damage characterization of UNS N10003 alloy based on a numerical simulation using the Norton creep law and Kachanov–Rabotnov creep damage model

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Nuclear Science and Techniques 2019年第4期30卷 114-122页

作者： xiao-Yan Wang xiao Wang xiao-Chun Zhang Shi-feng zhu Shanghai Institute of Applied Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

The calculation of inelastic creep damage is important for the structural integrity evaluation of the elevated temperature structure in a thorium molten salt reactor(TMSR). However, a creep damage theory model and numerical simulation method have not been proposed for the key materials(UNS N10003 alloy) in the TMSR. In this study, creep damage characterization of UNS N10003 alloy is investigated using the Norton creep law and Kachanov–Rabotnov(K–R) creep damage model. First, the creep experimental data of the UNS N10003 alloy at 650 °C were adopted to fit the material constants of the two models. Then, the creep damage behavior of the UNS N10003 alloy was analyzed and discussed under uniaxial and multi-axial stress states. The results indicated that the K–R creep damage model is more suitable for the UNS N10003 alloy than the Norton model. Finally, the numerical simulation method was developed by a user-defined UMAT subroutine and subsequently verified through a finite element analysis(FEA). The FEA results were in agreement with the theoretical solutions. This study provides an effective method for the inelastic creep damage analysis of the elevated temperature structure in the TMSR.

关键词： Thorium molten salt reactor UNS N10003 alloy Creep damage Inelastic analysis Elevated temperature structure

经尿道等离子前列腺电切术及术中快速病理诊治晚期前列腺癌的临床分析

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中国现代医学杂志 2015年第12期25卷 81-83页

作者：李向利关海英沈鹤清杨建伟陈晨朱晓峰江苏省苏州市相城人民医院泌尿外科江苏苏州215131

目的探讨经尿道等离子前列腺电切术及快速病理在晚期前列腺癌致膀胱出口梗阻的临床应用。方法12例患者均采用经尿道等离子前列腺电切术,术中快速病理均明确前列腺癌诊断,同时行加双侧睾丸切除术,术后3天开始应用氟他胺0.25 g,每天3次,口... 详细信息

目的探讨经尿道等离子前列腺电切术及快速病理在晚期前列腺癌致膀胱出口梗阻的临床应用。方法12例患者均采用经尿道等离子前列腺电切术,术中快速病理均明确前列腺癌诊断,同时行加双侧睾丸切除术,术后3天开始应用氟他胺0.25 g,每天3次,口服,3个月后复查血TPSA,TPSA〈2 ng/ml时,服药1个月后停药,停用后每个月复查PSA,当PSA〉4 ng/ml时再重新开始治疗。结果所有12例患者术后1个月国际前列腺症状评分（IPSS）下降至（9.0±1.2）分,最大尿流率（Qmax）上升为（17.5±2.3）ml/s,膀胱残余尿量为（40±25）ml。术后3个月9例TPSA〈2 ng/ml,另外3例降到术前的10%左右。TPSA、IPSS、Qmax及膀胱残余尿量均较术前有明显改善（P〈0.05）,随访1~5年8例患者仍健在。结论经尿道等离子前列腺电切术中快速病理可明确诊断,为手术去势提供诊断依据,联合最大限度雄激素阻断内分泌疗法可有效解除晚期前列腺癌致膀胱出口梗阻,提高了患者的生活质量。

关键词：前列腺癌等离子电切快速病理内分泌治疗

Dual Space SVDD Based Radar Target Recognition from HRRP

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Chinese Journal of Electronics 2014年第2期23卷 419-425页

作者： xiao Huaitie feng Guoyu zhu Yongfeng HUANG Mengjun Science and Technology on Automatic Target Recognition Laboratory National University of Defense Technology

In radar target recognition based on kernel method, Support vector data description(SVDD) has been applied to High resolution range profiles(HRRPs)recognition. In this paper, first, three distribution models,i.e., Membership model, Cloud model, Gaussian mixture model, are developed to describe distribution characteristics of HRRPs in extended space. Secondly, test HRRPs in multi-target hypersphere spaces are classified, in accordance with their multi-space distributing characteristics,into two types, i.e., shrink sample and slack sample. Determination of the property of a test sample is achieved by using the minimum relative distance for shrink samples and three distribution models for slack samples, respectively. Thus three HRRP recognition methods based on dual space SVDD are formed. The extensive experiment results for HRRPs of four planes show that the proposed methods have better recognition performance than the recognition method based on single space SVDD.

关键词： High resolution range profile Support vector data description Membership model Cloud model Gaussian mixture model

EXPERIMENTAL MEASUREMENT AND NUMERICAL SIMULATION FOR FLOW FIELD AND FILM COOLING EFFECTIVENESS IN FILM-COOLED TURBINE

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Journal of Hydrodynamics 2007年第4期19卷 459-466页

作者： YUAN feng zhu xiao-cheng DU Zhao-hui School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200030 China

Numerical simulation of three-dimensional flow field and film cooling effectiveness in film-cooled turbine rotor and stationary turbine cascade were carried out by using the k- ε turbulence model, and the predictions of the three-dimensional velocities were compared with the measured results by Laser-Doppler Velocimetry （LDV）. Results reveal the secondary flow near the blade surface in the wake region behind the jet hole. Compared with the stationary cascade, there are the centrifugal force and Coriolis force existing in the flow field of the turbine rotor, and these forces make the three-dimensional flow field change in the turbine rotor, especially for the radial velocity. The effect of rotation on the flow field and the film cooling effectiveness on the pressure side is more apparent than that on the suction side as is shown in the computational and measured results, and the low film cooling effectiveness appears on the pressure surface of the turbine rotor blade compared with that of the stationary cascade.

关键词： film-cooled cascade three-dimensional effectiveness Laser-Doppler simulation turbine rotor stationary turbine flow field film cooling Velocimetry (LDV) numerical

Thermodynamics of Aromatic Cyclic Ester Polymerization in Bulk

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Chinese Journal of Polymer Science 2019年第1期37卷 89-93页

作者： Chong He Xiang zhu xiao-Hong Li xiao-Ming Yang Ying-feng Tu Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application College of Chemistry Chemical Engineering and Materials ScienceSoochow University

We present here the thermodynamic investigation of in situ cascade polycondensation-coupling ring-opening polymerization(PROP)for three cyclic aromatic ester monomers,i.e.,cyclic oligo(2-methyl-1,3-propylene terephthalate)s(COMPTs),cyclic oligo(neopentylene terephthalate)s(CONTs)and cyclic oligo(2-methyl-2-propyl-1,3-propylene terephthalate)s(COMPPTs).The equibrium monomer to polymer weight ratio in bulk at different polymerization temperatures for each monomer was estimated by the size exclusion chromatography(SEC),and the thermodynamic parameters were estimated by Dainton *** different from the thermodynamics of aliphatic lactones polymerization,which is an exothermic process with entropy reduction,our results showed the polymerization thermodynamics for three cyclic aromatic ester monomers was a weak exothermic process with slight entropy increment,i.e.,a both enthalpy and entropy driving *** them,CONTs showed the largest value of enthalpy change,due to its symmetric dimethyl substitution onβ-position of propandiol segments.

关键词： Lactone Polyester Polycondensation-coupling ring-opening polymerization Thermodynamic parameters

Modified strict sperm morphology threshold aids in the clinical selection of conventional in vitro fertilization(IVF)or intracytoplasmic sperm injection(ICSI)

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Asian Journal of Andrology 2022年第1期24卷 62-66页

作者： Yong zhu feng Zhang Hua Cheng xiao-Xi Sun feng Jiang Obstetrics and Gynecology Hospital Fudan UniversityShanghai 200011China Shanghai Ji Ai Genetics and IVF Institute Obstetrics and Gynecology HospitalFudan UniversityShanghai 200011China

For infertility treatment,the selection of in vitro fertilization(IVF)or intracytoplasmic sperm injection(ICSI)is decided by multiplying indicators(including fallopian tube factors,semen count,and semen motility),except for sperm *** this study,we conducted a retrospective analysis,from implantation to birth,over a period of 5 years.A total of 1873 couples with primary or secondary fallopian tube factors and an increased defective sperm morphology rate(DSMR)were divided into different groups to receive IVF or ICSI *** comparing the outcomes,we found that the F1 group(DSMR98%,IVF group 3;P98%,ICSI group 3)had higher cleavage rate(P<0.001),biochemical pregnancy rate(P<0.05),clinical pregnancy rate(P<0.05)and live birth rate(P<0.05)than the F3 ***,the ICSI subgroup had a lower two pronuclei fertilization rate than the IVF subgroup(P<0.05).Our data suggest that the sperm morphology should also be considered when selecting IVF or ICSI combined with other semen parameters before the first assisted reproductive technologies(ART)cycle,especially for males with severe sperm defects.

关键词： clinical outcome in vitro fertilization intracytoplasmic sperm injection sperm morphology

Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao Yuan-Yuan zhu Liang-Jin Xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

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Transmission Index Research of Parallel Manipulators Based on Matrix Orthogonal Degree

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1396-1405页

作者： zhu-feng Shao Jiao Mo xiao-Qiang Tang Li-Ping Wang State Key Laboratory of Tribology and Institute of Manufacturing Engineering Tsinghua UniversityBeijing 100084 China Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control Tsinghua UniversityBeijing 100084 China

Performance index mance evaluation, and is the is the standard of perfor- foundation of both perfor- mance analysis and optimal design for the parallel manipulator. Seeking the suitable kinematic indices is always an important and challenging issue for the parallel manipulator. So far, there are extensive studies in this field, but few existing indices can meet all the requirements, such as simple, intuitive, and universal. To solve this problem, the matrix orthogonal degree is adopted, and generalized transmission indices that can evaluate motion/force trans- missibility of fully parallel manipulators are proposed. Transmission performance analysis of typical branches, end effectors, and parallel manipulators is given to illus- trate proposed indices and analysis methodology. Simula- tion and analysis results reveal that proposed transmission indices possess significant advantages, such as normalized finite （ranging from 0 to l）, dimensionally homogeneous, frame-free, intuitive and easy to calculate. Besides, pro- posed indices well indicate the good transmission region and relativity to the singularity with better resolution than the traditional local conditioning index, and provide a novel tool for kinematic analysis and optimal design of fully parallel manipulators.

关键词： Transmission index Parallel mechanism Kinematic performance Matrix orthogonal degree