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Hot Deformation Behaviors of S31042 Austenitic Heat-Resistant Steel

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Journal of Iron and Steel Research International 2011年第10期18卷 54-58,79页

作者： WANG Jing-zhong LIU gheng-dong CHENG Shi-chang bao han-sheng Central Iron and Steel Research Institute Beijing 100081 China School ot Metallurgy and Engineering Xi＇ an University of Architecture and Technology Xi＇an 710055 Shaanxi China

The hot deformation behavior of S31042 austenitic heat-resistant steel was investigated over the tempera- ture range of 900--1 200 ℃ and strain rate range of 0.01--10 s- 1 using hot compression tests and the corresponding flow curves were obtained. The hot deformation activation energy of the test steel is 625 kJ/mol. The hot deformation equation and the relationship between the peak stresses, deformation temperature and strain rate were set up. The Zener-Hollomon parameter under various conditions was determined. The relation between the Zener-Hollomon parameter and the microstructure evolution of test steel was discussed. With the decrease of Zener-Hollomon param- eter, the microstructure of test steel transforms from deformation instability to dynamic recovery, partial dynamic recrystallization, full dynamic recrystallization with equiaxial structure, and finally to full dynamic recrystaUization with mixed crystal structure. The deformation condition can be adjusted easily by utilizing the Zener-Hollomon pa- rameter to obtain equiaxial microstructure.

关键词： S31042 steel hot deformation behavior Zener-Hollomon parameter microstructure

Evolution of Precipitates of S31042 Heat Resistant Steel During 700℃ Aging

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Journal of Iron and Steel Research International 2013年第10期20卷 113-121页

作者： WANG Jing-zhong LIU Zheng-dong bao han-sheng CHENG Shi-chang Xi'an University of Architecture and Technology Central Iron and Steel Research Institute

The evolution of precipitates of S31042 steel during 700 ℃ aging was investigated by using a scanning elec- tron microscope, a transmission electron microscope, and electron energy spectrum technology. The various combi nations of M23C6, MX, NbCrN, and σ and G phases in the steel were found at different aging states. In the begin ning of aging, M23C6 precipitates swiftly along the grain boundaries. When the aging time exceeds 6 000 h, precipita- ted M23C6 carbides along the grain boundaries turn to be granular. It was found that Si element segregates to grain boundaries during above process, which may enhance the granular shape of M23C6 carbides and its transformation to and G phases. When the aging time exceeds 10 000 h, various shaped a phase and granular G phase appear along the grain boundaries and there are no continuous M23C6 carbides along the grain boundaries. Meanwhile, a large quantity of granular M23C6 carbides and a minor amount of G phase precipitate near the grain boundaries. Based on the segre- gation of silicon to the grain boundaries, a precipitation evolution model during aging was concluded.

关键词： S31042 heat resistant steel aging precipitation evolution

Hot Deformation Behavior of a New 9%Cr Heat Resistant Steel G115

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Journal of Iron and Steel Research International 2013年第9期20卷 73-79页

作者： YAN Peng LIU Zheng-dong LIU Wei bao han-sheng WENG Yu-qing Key Laboratory of Advanced Material of Ministry of Eclucation of China School of Materials Science and EngineeringTsinghua University Institute for Special Steels China Iron and Steel Research Institute

The hot deformation behavior of a new heat resistant steel Gl15 designed for 650 ℃ ultra-supercritical （USC） power plants was experimentally studied. Hot compression test was carried out in the temperature range of 900-1 200 ℃ and the strain rate range of 0.1-20 s i by using Gleeble 3800 thermal-mechanical simulator, and the corresponding flow curves were obtained. Experimental results show that the flow stress increases with the decrease of deformation temperature and the increase of strain rate. The hot deformation activation energy of G115 steel was determined to be 494 kJ/mol and the constitutive equation was also obtained. For convenience of the practical applica-tion, a good approximate equation was obtained for calculating the peak stress values of Gl15 steel under different deformation conditions. At the strain value of 0.9, natural logarithm of the critical Zener Hollomon parameter Zc of Gl15 steel was determined to be in the scope of 49.67 and 50.65, above which there will be no dynamic recrystalliza-tion （DRX）. And natural logarithm of the critical Zener-Hollomon parameter Zc of Gl15 steel was determined to be in the scopes of 45.58 and 46.27, below which full DRX may occur. Then, the status diagram of dynamic micro structures of G115 steel was established. In addition, the strain rate sensitivity of Gl15 steel is not constant during the test temperature range and it increases linearly from 900 to 1 200 ℃. Therefore, hot deformation at higher tem- peratures would obtain better workability.

关键词： heat resistant steel G115 hot deformation dynamic recrystallization constitutive equation Zener Hol-lomon parameter

Advantages and limitations of the parthenogenetic embryonic stem cells in cell therapy

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Journal of Reproduction and Contraception 2016年第2期27卷 118-124页

作者： Zhao-yang YU bao-sheng han North China University of Science and Technology Department of Reproduction and Genetics Maternity and Child Health Care HospitalTangshan

Parthenogenetic embryonic stem cells（pE SCs）, as ＂seed cells＂ for regenerative medicine, are an effective way to build patient-specific pluripotent stem cells, due to the fact that characteristics of self-renewal and pluripotent are similar to embryonic stem cells（ESCs）. Parthenogenetic activation can be performed at meiosis I or meiosis II describing the embryos with distinct patterns of homozygosity and *** pE SCs are expected to be used for autologous transplantation, while homozygous pE SCs enable to be used for allogeneic gene therapy in theory but is hampered by immunological barriers defined by the recognition of natural killer（NK）cells. In this review, we describe the mechanism of deriving heterozygous and homozygous pE SCs, and summarize the advantages and limitations of pE SCs in the area of cell therapy.

关键词： parthenogenetic embryonic stem cells(pESCs) heterozygous homozygous advantages and limitations cell therapy

Effect of Ageing at 700℃ on Microstructure and Mechanical Properties of S31042 Heat Resistant Steel

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Journal of Iron and Steel Research International 2013年第4期20卷 54-58页

作者： WANG Jing-zhong LIU Zheng-dong bao han-sheng CHENG Shi-chang WANG Bin School of Metallurgy and Engineering Xi'an University of Architecture and Technology Institute for Structural Materials China Iron and Steel Research Institute Group

To investigate the effect of high temperature ageing on the microstructure and mechanical properties of S31042steel,solid solution treatment at 700℃ was carried out for various time from 10to 6 *** results showed that the change of mechanical properties is closely related to the amount of precipitated *** ageing from 10to 300h,precipitation in the tested steel increases rapidly,and correspondingly,the high temperature yield strength and room temperature hardness of tested steel increase ***,the thickness of the secondary phase on grain boundaries widens sharply and the room temperature Charpy impact absorb energy *** beyond 300h,the precipitation in the steel increases gradually and the precipitates coarsen to a certain *** high temperature yield strength of the steel keeps stable,and the room temperature Charpy impact energy and hardness decrease *** beyond 3 000h,the mechanical properties of the steel tend to be *** main precipitates are M23C6,NbCrN and NbC in the tested steel.

关键词： ageing microstructure mechanical property precipitated phase

Altered microRNA expression profiles of human spermatozoa in normal fertile men of different ages

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Asian Journal of Andrology 2023年第6期25卷 737-744页

作者： Ming-Jia Zhao Yao-Nan Zhang Yong-Ping Zhao Xian-Bing Chen bao-sheng han Ning Ding Yi-Qun Gu Shu-Song Wang Jing Ma Mei-Ling Liu Graduate School of Peking Union Medical College Peking Union Medical CollegeChinese Academy of Medical SciencesBeijing 100730China National Health Commission Key Laboratory of Male Reproductive Health National Research Institute for Family PlanningBeijing 100081China Department of Reproduction and Genetics Maternity and Child Health Care HospitalTangshan 063000China Department of Family Planning and Reproductive Medicine Peking University People’s HospitalBeijing 100081China Hebei Key Laboratory of Reproductive Medicine Hebei Institute of Reproductive Health Science and TechnologyShijiazhuang 050071China

MicroRNAs(miRNAs)are mediators of the aging *** purpose of this work was to analyze the miRNA expression profiles of spermatozoa from men of different ages with normal ***-seven donors were divided into three groups by age(Group A,n=8,age:20–30 years;Group B,n=10,age:31–40 years;and Group C,n=9,age:41–55 years)for high-throughput sequencing *** from 65 individuals(22,22,and 21 in Groups A,B,and C,respectively)were used for validation by quantitative real-time polymerase chain reaction(qRT-PCR).A total of 2160 miRNAs were detected:1223 were known,937 were newly discovered and unnamed,of which 191 were expressed in all donors.A total of 7,5,and 17 differentially expressed microRNAs(DEMs)were found in Group A vs B,Group B vs C,and Group A vs C comparisons,***-two miRNAs were statistically correlated with *** miRNAs were identified as age-associated miRNAs,including hsa-miR-127-3p,mmu-miR-5100_L+2R-1,efu-miR-9226_L-2_1ss22GA,cgr-miR-1260_L+1,hsa-miR-652-3p_R+1,pal-miR-9993a-3p_L+2R-1,hsa-miR-7977_1ss6AG,hsa-miR-106b-3p_R-1,hsa-miR-186-5p,PC-3p-59611_111,hsa-miR-93-3p_R+1,and aeca-mir-8986ap5_*** were 9165 target genes of age-associated *** Ontology(GO)analysis of the target genes identified revealed enrichment of protein binding,membrane,cell cycle,and so *** Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis of age-related miRNAs for target genes revealed 139 enriched pathways,such as signaling pathways regulating stem cell pluripotency,metabolic pathways,and the Hippo signaling *** suggests that miRNAs play a key role in male fertility changes with increasing age and provides new evidence for the study of the mechanism of age-related male fertility decline.

关键词： age fertility microRNA spermatozoa

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折返装置在煤矿可伸缩带式输送机上的应用

煤矿机械 2010年第12期31卷 165-166页

作者：韩宝生宝鸡杭叉工程机械有限责任公司陕西宝鸡721004

介绍了折返装置在煤矿可伸缩带式输送机中的应用,叙述其设计要点及工作原理、安装布置方式、维护保养注意事项。使用结果表明,该装置简单实用,能有效防止飘带,适合在4～12°变坡的综采工作面巷道使用。

关键词：带式输送机折返装置防止飘带

Correlation of body mass index with Th1/Th2 balance, adhesion molecules and insulin signal transduction in infertile patients

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Journal of Hainan Medical University 2017年第21期23卷 60-63页

作者： Hui-Juan Zhang bao-sheng han Gui-Ling Fan Nv Geng Juan Li Dong-Ting Liu Department of Reproductive Genetics Tangshan Maternal and Child Health Hospital in Hebei ProvinceTangshan CityHebei Province063000 Department of Obstetrics and Gynecology Tangshan Maternal and Child Health Hospital in Hebei ProvinceTangshan CityHebei Province063000

Objective: To study the correlation of body mass index with Th1/Th2 balance, adhesion molecules and insulin signal transduction in infertile patients. Methods: A total of 132 patients who received diagnostic curettage due to infertility in Tangshan Maternal and Child Health Hospital between June 2015 and March 2016 were selected as the research subjects and divided into the normal group with BMI 30 kg/m2 according to BMI, and the levels of Th1/Th2 cytokines in serum as well as the expression of Th1/Th2 transcription factors, adhesion molecules and insulin signal pathway molecules in endometrial tissue were detected. Results:IFN-γ and TNF-α levels in serum of obesity group and overweight group were significantly higher than those of control group while IL-4, IL-5 and IL-13 levels in serum as well as CD44V6, N-cadherin, FAK, ICAM-1, GLUT-4, IRS-1, PI3K and AKT mRNA expression in endometrial tissue were significantly lower than those of control group;IFN-γ and TNF-α levels in serum of obesity group were significantly higher than those of overweight group while IL-4, IL-5 and IL-13 levels in serum as well as CD44V6, N-cadherin, FAK, ICAM-1, GLUT-4, IRS-1, PI3K and AKT mRNA expression in endometrial tissue were significantly lower than those of overweight group. Conclusion: Weight gain can aggravate the Th1/Th2 disorder, reduce the adhesion molecule expression and hinder the insulin signal transduction in infertile patients.

关键词： Infertility Body mass index Immune response Adhesion molecule Insulin resistance

2Cr12NiMo1W1V超临界汽轮机叶片用耐热钢的热变形行为

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钢铁 2019年第3期54卷 63-68页

作者：龚志华何禛包汉生杨钢钢铁研究总院特殊钢研究所北京100811 内蒙古科技大学材料与冶金学院内蒙古包头014010 钢铁研究总院科技信息与战略研究所北京100081

为了解决2Cr12NiMo1W1V耐热钢在锻造过程中晶粒粗大和组织不均匀的问题,利用Gleeble-3800热模拟试验机,在变形温度为1 000～1 200℃、应变速率为0.01～10 s-1、变形量为70%的条件下,研究和分析了2Cr12NiMo1W1V耐热钢的高温塑性变形和动... 详细信息

为了解决2Cr12NiMo1W1V耐热钢在锻造过程中晶粒粗大和组织不均匀的问题,利用Gleeble-3800热模拟试验机,在变形温度为1 000～1 200℃、应变速率为0.01～10 s-1、变形量为70%的条件下,研究和分析了2Cr12NiMo1W1V耐热钢的高温塑性变形和动态再结晶行为。结果表明,该耐热钢的真应力-应变曲线具有动态再结晶特征。再结晶晶粒尺寸随着变形温度的增加或应变速率的降低呈增加趋势,在变形温度为1 150～1 200℃,应变速率为0.01 s-1时,晶粒尺寸急剧增加。在真应力-应变曲线的基础上,建立了材料热变形本构方程,其热激活能为453.74 kJ/mol。根据峰值应力绘制了合金的热加工图并获得在各加工条件下的效率值,合金的最佳热加工区间为变形温度为1 000～1 150℃、应变速率为0.1～1 s-1以及变形温度为1 060～1 125℃、应变速率为0.1～10 s-1。

关键词：汽轮机叶片热变形热加工图动态再结晶本构方程