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Tensile Properties of TWIP Steel at High Strain Rate

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Journal of Iron and Steel Research International 2009年第1期16卷 81-86,21页

作者： XIONG Rong-gang FU Ren-yu SU yu li qian WEI Xi-cheng li lin School of Materials Science and Engineering Shanghai University Shanghai 200072 China

Tensile tests of TWIP steels of two compositions are performed in the strain rate range of 10^-5-10^3 s^-1. Results indicate that steel 1^# does not exhibit TWIP effect but deformation-induced martensitic transformation appears only. There exists TWIP effect in steel 3^# . Tensile properties at room temperature are sensitive to strain rate in the studied strain rate ranges. Analysis on the relationship between strain-hardening exponent and strain rates shows that strain induced martensitic transformation and formation of twins during deformation have significant in- fluence on their strain-hardening behavior.

关键词： twin-induced plasticity strain rate strain hardening deformation twin

Accuracy of a combined score of zygote and embryo morphology for selecting the best embryos for IVF

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第8期9卷 649-655页

作者： yu-li qian Ying-hui YE Chen-ming XU Fan JIN He-feng HUANG Department of Reproductive Endocrinology Women＇s Hospital School of Medicine Zhejiang University Hangzhou 310006 China

Objective:To evaluate the accuracy of a scoring system combining zygote and embryo morphology in predicting the outcome of in vitro fertilization (IVF) treatment. Methods: In a study group, 117 consecutive IVF or intracytoplasmic sperm injection (ICSI) cycles with embryo transfer were carried out and 312 embryos were scored using a combined scoring system (CSS) of zygote and embryo morphology before transplantation. In a control group, a total of 420 IVF or ICSI cycles were carried out and 1176 embryos were scored using a cumulative embryo score (CES). The effects of the combined scoring system on the embryo implantation rate and pregnancy rate per cycle were analyzed. Results: Using the combined scoring system, the embryo implan-tation rate (27.6%) and the clinical pregnancy rate (48.7%) were significantly higher than those in the control group (20.8% and 38.6%, respectively). Also, the implantation rate of embryos scoring ≥70 (38.5%: 82 sacs/213 embryos) was significantly higher (P<0.001) than that of embryos scoring <70 (4%: 4 sacs/99 embryos). The pregnancy rate of patients with embryos scoring ≥70 using the combined scoring system (66.7%) was significantly higher (P<0.001) than that of patients with embryos scoring ≥20 using the cumulative embryo score (59.0%). Conclusion: The results suggest that selecting embryos with a high score (≥70) using the combined scoring system could increase the implantation rate and pregnancy rate, and that using a scoring system combining assessments of human zygotes and pre-implantation embryos might predict IVF outcomes more accurately than using a cumula-tive embryo score.

关键词： Embryo score Combined scoring system (CSS) Implantation In vitro fertilization (IVF) Pregnancy

Preparation and Characterization of Polymer－Supported Rare Earth Complexes

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Chemical Research in Chinese Universities 1995年第4期11卷 342-353页

作者： yu Guang-qian and li yu-liang(Changchun Institute of Applied Chemistry,Academia Sinica,Changchun,130022)Ll Xiao-li(Department of Chemistry,Changchun Normal College, College, Changchun,130032) ACAD SINICA CHANGCHUN INST APPL CHEMCHANGCHUN 130022PEOPLES R CHINA CHANGCHUN NORMAL COLL DEPT CHEMCHANGCHUN 130032PEOPLES R CHINA

he polymers containing different ligand groups of atoms(mainly O,N,and S)and their rare earth complexes were prepared,characterized and classified based on the type of metal-ligand bonding. The catalytic activities of the complexes are briefly *** polymer- supported rare earth complexes shwed much greater activities than the correspond- ing complexes with a low molecular weight.

关键词： Rare earth complexes Polymer-support Butadiene polymerization Catalytic activities.

Comparison of semen quality and outcome of assisted reproductive techniques in Chinese men with and without hepatitis B

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Asian Journal of Andrology 2011年第3期13卷 465-469,513,514页

作者： Xu-Ping Zhou Xiao-ling Hu Yi-Min Zhu Fan Qu Sai-lun Sun yu-li qian Key Laboratory of Women＇s Reproductive Health of Zhejiang Province Hangzhou 310006 China Department of Reproductive Endocrinology Women＇s Hospital School of Medicine Zhejiang University Hangzhou 310006 China Department of Reproductive Endocrinology The First Affiliated Hospital of Zhejiang Medical University Hangzhou 310006 China

In this study, we aimed to determine the effects of hepatitis B virus （HBV） infection on sperm quality and the outcome of assisted reproductive technology （ART）. A total of 916 men （457 HBV-positive and 459 HBV-negative） seeking fertility assistance from January 2008 to December 2009 at the Women＇s Hospital in the School of Medicine at Zhejiang University were analysed for semen parameters. Couples in which the men were hepatitis B surface antigen （HBsAg）-seropositive were categorized as HBV-positive and included 587 in vitrofertilisation （IVF） and 325 intracytoplasmic sperm injection （ICSI） cycles from January 2004 to December 2009; negative controls were matched for female age, date of ova retrieval, ART approach used （IVF or ICSI） and randomized in a ratio of 1：1 according to the ART treatment cycles （587 for IVF and 325 for ICSI）. HBV-infected men exhibited lower semen volume, lower total sperm count as well as poor sperm motility and morphology （P〈O.05） when compared to control individuals. Rates of two-pronuclear （2PN） fertilisation, high-grade embryo acquisition, implantation and clinical pregnancy were also lower among HBV-positive patients compared to those of HBV-negative patients after ICSI and embryo transfer （P〈0.05）; IVF outcomes were similar between the two groups （P〉0.05）. Logistic regression analysis showed that HBV infection independently contributed to increased rates of asthenozoospermia and oligozoospermia/azoospermia （P〈0.05） as well as decreased rates of implantation and clinical pregnancy in ICSI cycles （P〈0.05）. Our results suggest that HBV infection in men is associated with poor sperm quality and worse ICSI and embryo transfer outcomes but does not affect the outcome of IVF and embryo transfer.

关键词： hepatitis B virus infection infertility intracytoplasmic sperm injection in vitrofertilisation male infertility sperm sperm motility

Trends in lipids Level and Dyslipidemia among Chinese Adults, 2002-2015

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Biomedical and Environmental Sciences 2019年第8期32卷 559-570页

作者： SONG Peng Kun MAN Qing Qing li Hong PANG Shao Jie JIA Shan Shan li yu qian HE li ZHAO Wen Hua ZHANG Jian National Institute for Nutrition and Health Chinese Center for Disease Control and PreventionBeijing 100050China Central laboratory of Beijing Center for Disease Control and Prevention Beijing 100013China Academy of National Food and Strategic Reserves Administration Beijing 100037China

Objective To investigate the trends of lipid profiles and dyslipidemia among Chinese adults from 2002 to *** Data were collected from three nationally representative cross-sectional *** venous blood samples were collected and serum lipids were tested by biochemical analysis and enzymatic *** levels and the prevalence of dyslipidemia among adults were analyzed with complex sampling weighting adjustment for age and *** The weighted means of TC, TG, and LDL-c significantly increased linearly from 3.93, 1.12, and 2.12 mmol/L in 2002 to 4.59, 1.41, and 2.78 mmol/L in 2010 and then to 4.63, 1.47, and 2.87 mmol/L in 2015, respectively;by contrast, HDL-c levels decreased significantly from 1.30 mmol/L to 1.26 mmol/L over the same *** trends in mean non-HDL-c and lipid-related ratios were *** weighted dyslipidemia prevalence linearly increased;in particular, hypercholesterolemia increased from 1.6% to 5.6% and then to 5.8%, hypertriglyceridemia increased from 5.7% to 13.6% and then to 15.0%, low HDL-c increased from 18.8% to 35.5% and then to 24.9%, and high LDL-c increased from 1.3% to 5.6% and then to 7.2%(P for trend lipidemia increased among Chinese adults from 2002 to *** of a comprehensive strategy to decrease lipid levels in this population is urgently required.

关键词： lipids Dyslipidemia Cross-sectional study Adults China

机械牵拉对人支气管上皮样细胞气道重塑相关因子表达的影响

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生物医学工程学杂志 2016年第5期33卷 923-930页

作者：余倩李敏超重庆医科大学附属第二医院呼吸内科重庆400010

本文为了研究机械牵拉人支气管上皮样细胞(16HBE)对转化生长因子-β1(TGF-β1)、成纤维细胞生长因子-2(FGF-2)表达的影响及其相关信号转导机制。采用柔性基底加载装置(FX-4000T)牵拉16HBE细胞,参数设置为拉伸幅度15%,频率1Hz,加载时间... 详细信息

本文为了研究机械牵拉人支气管上皮样细胞(16HBE)对转化生长因子-β1(TGF-β1)、成纤维细胞生长因子-2(FGF-2)表达的影响及其相关信号转导机制。采用柔性基底加载装置(FX-4000T)牵拉16HBE细胞,参数设置为拉伸幅度15%,频率1Hz,加载时间分别为:0.5h、1h、1.5h、2h。选择TGF-β1、FGF-2和Ca^(2+)表达较高的一组以经典瞬时感受器电位1(TRPC1)抑制剂SKF96365、蛋白激酶C(PKC)抑制剂HA-100干预。发现与空白对照组相比,4个时间段TGF-β1、FGF-2和Ca^(2+)的表达均高于空白对照组,差异有统计学意义(P<0.05),在0.5h时其增幅最大。对0.5h机械牵拉组予以SKF96365、HA-100干预,其TGF-β1、FGF-2和Ca^(2+)的表达均较0.5h机械牵拉组降低,差异有统计学意义(P<0.05)。本文研究结果说明,机械牵拉16HBE细胞可导致气道重塑相关因子表达增加,PKC、TRPC1、Ca^(2+)可能参与了该信号通路。

关键词：机械牵拉人支气管上皮样细胞转化生长因子-β1 成纤维细胞生长因子2

The Synthesis of Neodymium Complexes with Polymers Containing Thiol and Sulphoxide and Their Catalytic Activities

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Chemical Research in Chinese Universities 1993年第4期9卷 364-366页

作者： QU Ya-huan and li Xiao-li (Department of Chemistry, Changchun Normal College, Changchun, 130032)yu Guang-qian and li yu-liang (Changchun Institute of Applied Chemistry, Academia Sinica, Changchun, 130022)

Introduction Polymers containing thiol and sulphoxide which have active—SH and—SO groups respectively, have wide application to biological, pharmaceutical, industrial and other chemical field and—SH and—SO groups are easy to form complexes with metals, so they have aroused an increasing interest of many authors. A large number of functional resins and corresponding metal complexes have been synthesized.

关键词： Neodymium complexes Polymers Thiol Sulphoxide Catalytic activities

The Mechanism of Heating Rate on the Secondary Recrystallization Evolution in Grain Oriented Silicon Steel

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 275-282页

作者： GAO qian li Jun WANG Xianhui CAO Laifu GONG Jian li Bo Central Iron and Steel Research Institute Group Beijing 100081China Shougang Zhixin Electromagnetic Material R&D(Beijing)Co. Ltd.Beijing 101300China Beijing Shougang Co. Ltd.Qian’an 064404China

Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were *** illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically *** effect of precipitate ripening on the Goss texture and magnetic property was *** indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate *** recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}oriented grains growing abnormally and a magnetic induction intensity of ***,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss ***,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 *** a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this *** heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties.

关键词： high temperature annealing heating rate secondary recrystallization grain oriented silicon steel

从知识失业现象分析我国高校文科建设——兼论文科招生规模与教育教学质量的统一

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河北师范大学学报（教育科学版） 2010年第4期12卷 19-24页

作者：李豫黔四川大学中美大学战略规划研究所四川成都610065

我国高等教育自1999年扩招以后实现了由精英教育向大众化教育的转型,然而我国高校文科建设却不尽如人意,没有能够跟上教育转型的步伐。在知识失业日趋深入的时代背景下,文科生知识失业尤其显得突出。建设具有深厚功力和蓬勃活力的文科,... 详细信息

我国高等教育自1999年扩招以后实现了由精英教育向大众化教育的转型,然而我国高校文科建设却不尽如人意,没有能够跟上教育转型的步伐。在知识失业日趋深入的时代背景下,文科生知识失业尤其显得突出。建设具有深厚功力和蓬勃活力的文科,是大学一项刻不容缓的事业。透过文科生就业这个表象问题,探究并解决高等文科教育的发展规模、质量以及如何体现高深专门知识的教与学等实质性症结已经迫在眉睫。

关键词：知识失业文科建设教学质量文科