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纤维增强钛基复合材料结构强度计算模型建立与修正方法

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推进技术 2023年第1期44卷 196-205页

作者：沙云东黄靖轩骆丽周颖沈阳航空航天大学航空发动机学院、辽宁省航空推进系统先进测试技术重点实验室辽宁沈阳110136

为了对SiC纤维增强钛基复合材料结构强度进行准确预测,基于宏-细观力学跨尺度分析方法,对复合材料强度进行计算。建立了复合材料层合板的有限元仿真计算模型,对复合材料层合板在横向拉伸与压缩载荷作用下的损伤演化及失效强度进行预测,... 详细信息

为了对SiC纤维增强钛基复合材料结构强度进行准确预测,基于宏-细观力学跨尺度分析方法,对复合材料强度进行计算。建立了复合材料层合板的有限元仿真计算模型,对复合材料层合板在横向拉伸与压缩载荷作用下的损伤演化及失效强度进行预测,并进行试验验证。建立细观力学代表体积元(RVE)模型,对模型施加周期性边界条件,实现横向拉、压载荷下基体的应力集中系数以及失效强度的计算。考虑结构实际受载中,复合材料的界面开裂对横向强度的影响,对模型进行修正,分析界面开裂的过程,计算修正后模型的应力集中系数以及失效强度,修正后的模型预测精度提升6.51%,与试验值误差为24.17%,验证了纤维增强复合材料强度计算方法的有效性。

关键词：纤维增强复合材料宏-细观力学应力集中系数结构强度模型修正界面开裂

Lunar Penetrating Radar onboard the Chang'e-3 mission

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Research in Astronomy and Astrophysics 2014年第12期14卷 1607-1622页

作者： Guang-You Fang Bin zhou Yi-Cai Ji Qun-ying Zhang Shao-Xiang Shen Yu-Xi Li Hong-Fei Guan Chuan-Jun Tang Yun-Ze Gao Wei Lu Sheng-Bo Ye Hai-Dong Han Jin Zheng Shu-Zhi Wang Institute of Electronics Chinese Academy of Sciences

Lunar Penetrating Radar （LPR） is one of the important scientific instru- ments onboard the Chang＇e-3 spacecraft. Its scientific goals are the mapping of lunar regolith and detection of subsurface geologic structures. This paper describes the goals of the mission, as well as the basic principles, design, composition and achievements of the LPR. Finally, experiments on a glacier and the lunar surface are analyzed.

关键词： Chang'e-3 mission -- moon rover -- Lunar Penetrating Radar

Association of gestational anemia with pregnancy conditions and outcomes: A nested case-control study

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World Journal of Clinical Cases 2021年第27期9卷 8008-8019页

作者： Yin Sun Zhong-zhou Shen Fei-Ling Huang Yu Jiang Ya-Wen Wang Su-Han Zhang Shuai Ma Jun-Tao Liu Yong-Le Zhan Hang Lin Yun-Li Chen ying-Jie Shi Liang-Kun Ma Department of Obstetrics and Gynecology Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeNational Clinical Research Center for Obstetric&Gynecologic DiseasesBeijing 100730China Department of Epidemiology and Biostatistics School of Population Medicine and Public HealthChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China

BACKGROUND Gestational anemia is a serious public health problem that affects pregnant women *** conditions and outcomes might be associated with the presence of gestational *** study investigated the association of pregnancy characteristics with anemia,exploring the potential etiology of the *** To assess the association of pregnancy parameters with gestational *** A nested case-control study was conducted based on the Chinese Pregnant Women Cohort Study-Peking Union Medical College Project(CPWCS-PUMC).A total of 3172 women were *** characteristics and gestational anemia occurrence were extracted,and univariable and multivariable logistic regression models were used to analyze the association of pregnancy parameters with gestational *** Among the 3172 women,14.0% were anemic,46.4% were 25-30 years of age,21.9%resided in eastern,15.7%in middle,12.4%in western 18.0% in southern and 32.0%in northern regions of *** women(65.0%)had a normal prepregnancy body mass *** analysis found that the occurrence of gestational anemia was lower in the middle and western regions than that in the eastern region[odds ratio(OR)=0.406,95%confidence interval(CI):0.309-0.533,P<0.001],higher in the northern than in the southern region(OR=7.169,95% CI:5.139-10.003,P<0.001),lower in full-term than in premature births(OR=0.491,95% CI:0.316-0.763,P=0.002),and higher in cases with premature membrane rupture(OR=1.404,95% CI:1.051-1.876,P=0.02).CONCLUSION Gestational anemia continues to be a health problem in China,and geographical factors may contribute to the *** birth and premature membrane rupture may be associated with gestational ***,we should vigorously promote local policy reformation to adapt to the demographic characteristics of at-risk pregnant women,which would potentially reduce the occurrence of gestational anemia.

关键词： Anemia Body mass index Gestational weight gain Pregnancy Pregnancy outcomes

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试论近水平煤层采场的3种基本结构形式

煤炭学报 2016年第10期41卷 2576-2587页

作者：冯军发周英李回贵刘闯河南理工大学能源科学与工程学院河南焦作454000 河南理工大学河南省高等学校深部矿井建设重点学科开放实验室河南焦作454000

基于煤层开挖力学效应和覆岩运动规律,揭示了覆岩破坏垮落过程中产生的压力拱和结构拱现象,研究了结构拱与压力拱的内在统一关系,提出了煤矿采场压力拱的3种形式。在此基础上,根据理论分析、相似模拟和数值模拟研究成果,认为近水平煤层... 详细信息

基于煤层开挖力学效应和覆岩运动规律,揭示了覆岩破坏垮落过程中产生的压力拱和结构拱现象,研究了结构拱与压力拱的内在统一关系,提出了煤矿采场压力拱的3种形式。在此基础上,根据理论分析、相似模拟和数值模拟研究成果,认为近水平煤层采场存在围岩承载结构、矿压运动结构和工作面防护结构3种形式,分别简称为"大结构"、"小结构"和"微结构",并研究了3种结构的具体形式和矿压显现的关系,得到了煤柱与采场大结构的关系。并针对神东矿区浅埋近距离煤层下层煤开采出煤柱时发生的压架事故案例,从压架前、后采场的3种基本形式的变化分析事故发生的原因,并提出了防治对策。

关键词：近水平煤层采场结构形式矿压显现压架事故

A wave of Foxp3^(+) regulatory T cell accumulation in the neonatal liver plays unique roles in maintaining self-tolerance

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Cellular & Molecular Immunology 2020年第5期17卷 507-518页

作者： Mingyang Li Weijia Zhao Yifan Wang Lixue Jin Gaowen Jin Xiuyuan Sun Wei Wang Ke Wang Xi Xu Jie Hao Rong Jin Wenxian Fu ying Sun yingjun Chang Xiaojun Huang Xuyu zhou Hounan Wu Kunshan Zhang Qing Ge Department of Immunology School of Basic Medical SciencesNHC Key Laboratory of Medical ImmunologyPeking UniversityBeijingChina Center for Molecular Metabolism Nanjing University of Science&TechnologyNo.364 Building200 Xiaolinwei StreetNanjing 210094China Pediatric Diabetes Research Center Department of PediatricsUCSDLa JollaCAUSA Department of Immunology School of Basic Medical SciencesCapital Medical UniversityBeijingChina Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation Peking University People’s Hospital&Institute of HematologyBeijing 100044China Institute of Microbiology Chinese Academy of SciencesBeijing 100101China Peking University Medical and Health Analytical Center Peking UniversityBeijing 100191China Translational Stem Cell Research Center Tongji HospitalTongji University School of MedicineShanghai 200065China Department of Integration of Chinese and Western Medicine School of Basic Medical SciencesPeking UniversityBeijing 100191China

Newborn animals require tightly regulated local and systemic immune environments to govern the development and maturation of multiple organs/tissues even though the immune system itself is far from mature during the neonatal *** T cells(Tregs)are essential for maintaining immune tolerance/homeostasis and modulating inflammatory *** features of Tregs in the neonatal liver under steady-state conditions are not well *** present study aimed to investigate the phenotype,functions,and significance of neonatal Tregs in the *** found a wave of thymus-derived Treg influx into the liver during 1–2 weeks of *** of these Tregs between days 7 and 11 after birth rapidly resulted in Th1-type liver inflammation and metabolic *** Tregs in the neonatal liver than in the spleen underwent MHC II-dependent activation and proliferation,and the liver Tregs acquired stronger suppressive *** transcriptomic profile of these neonatal liver Tregs showed elevated expression of PPARγand T-bet and features of Tregs that utilize lipid metabolic machinery and are capable of regulating Th1 *** accumulation of Tregs with unique features in the neonatal liver is critical to ensure self-tolerance and liver maturation.

关键词： Neonatal period liver Foxp3 Treg cells Th1-type inflammation

SUMO-1 modification regulates ATRA-induced differentiation via stabilization of RARα

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SUMO-1 modification regulates ATRA-induced differentiation v...

电场与硫酸盐侵蚀共同作用下混凝土的劣化及其机理

第八届中国肿瘤学术大会暨第十三届海峡两岸肿瘤学术会议

作者： Qian zhou Siyue Lou Bo Yang Qiaojun He Meidan ying Institute of Pharmacology ＆ Toxicology College of Pharmaceutical Sciences Zhejiang University

＜正＞Objective SUMO-1 modification has been implicated in many important cellular processes,including apoptosis,proliferation,and development,but its role in ATRA-induced differentiation processes of cancer cells rem...

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硅酸盐学报 2016年第2期44卷 239-245页

作者：黄谦王冲杨长辉周莹张超重庆大学材料科学与工程学院重庆400045

通过试验模拟电场与硫酸盐的共存环境,测试了不同配比的混凝土在这两种因素共同作用后的外观、抗压强度等宏观性能变化,并借助能谱分析、扫描电子显微镜和X射线衍射等方法,探讨了混凝土的劣化机理。结果表明:在电场作用下,混凝土孔溶液... 详细信息

通过试验模拟电场与硫酸盐的共存环境,测试了不同配比的混凝土在这两种因素共同作用后的外观、抗压强度等宏观性能变化,并借助能谱分析、扫描电子显微镜和X射线衍射等方法,探讨了混凝土的劣化机理。结果表明:在电场作用下,混凝土孔溶液中的Ca2+发生定向迁移从而导致Ca2+浓度降低;Ca(OH)2分解溶出Ca2+来维持其平衡;此外,水化硅酸钙(C-S-H)凝胶的Ca/Si比下降,表明C-S-H凝胶也分解析出Ca2+,这对强度产生不利影响。同时,大量SO42–因电场作用从阴极溶液进入混凝土内部,并与水泥水化产物反应生成更多钙矾石和石膏晶体,导致强度进一步降低。低水胶比或掺粉煤灰混凝土的耐蚀性有所提高,但其劣化仍较为明显。因此,当混凝土受到电场和硫酸盐侵蚀共同作用时,应针对性地提出更为合理的混凝土耐久性设计及防范措施。

关键词：混凝土电场硫酸盐侵蚀劣化机理

Functional identification of AtHsp90.3 in Saccharomyces cerevisiae and Arabidopsis thaliana under heat stress

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Functional identification of AtHsp90.3 in Saccharomyces cere...

华东六省一市生物化学与分子生物学会2010年学术交流会

作者： Xiangbin Xu Hongmiao Song Zhenhua zhou Qicai ying Huizhong Wang College of Life and Environmental Sciences Hangzhou Normal UniversityHangzhou College of Life and Environmental SciencesHangzhou Normal University

The function of cytosolic AtHsp90.3 was characterized by complementing the Saccharomyces cerevisiae endogenous Hsp90 genes and overexpressing it in Arabidopsis *** AtHsp90.3 supported the yeast growth under heat stress,in Arabidopsis,compared to the wild type, the transgenic plants overexpressing cytosolic AtHsp90.3 showed reduced tolerance to heat stress with lower germination rate and higher mortality rate,and more tolerant to high ***

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多孔介质中晶体的结晶压力分析

岩土工程学报 2019年第6期41卷 1158-1163页

作者：周凤玺应赛蔡袁强兰州理工大学土木工程学院甘肃兰州730050 浙江工业大学建筑工程学院浙江杭州310014 长江师范学院建筑物全生命周期健康检测与灾害防治工程研究中心重庆408100

孔隙溶液中结晶体产生的结晶压力是多孔材料宏观上形成介质变形、冻胀破坏的重要因素之一。以溶液–晶体的化学势平衡为基础,考虑了溶液中的粒子相互作用,分别对以过饱和比为驱动的盐分结晶体和以温度为驱动的冰结晶体进行了理论分析,... 详细信息

孔隙溶液中结晶体产生的结晶压力是多孔材料宏观上形成介质变形、冻胀破坏的重要因素之一。以溶液–晶体的化学势平衡为基础,考虑了溶液中的粒子相互作用,分别对以过饱和比为驱动的盐分结晶体和以温度为驱动的冰结晶体进行了理论分析,建立了非理想溶液中晶体对孔壁产生的最大结晶压力模型,并对溶液的冰点温度进行了分析。以NaCl溶液和Na2SO4溶液为例,分别对不同浓度和不同温度下的盐、水结晶压力及冰点温度进行了参数分析。结果表明:对于盐分结晶体,其结晶压力与溶液的过饱和比、溶液活度以及结晶盐的类型密切相关;对于冰晶体,其结晶压力与环境温度以及溶液的活度相关。

关键词：孔隙介质结晶压力冰点温度化学势