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On the thermodynamics of plasticity during quasi-isentropic compression of metallic glass

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Matter and Radiation at Extremes 2024年第2期9卷 74-89页

作者： Kaiguo Chen Bo Chen Yinan Cui yuying yu Jidong yu Huayun Geng Dongdong Kang Jianhua Wu Yao Shen Jiayu Dai College of Science National University of Defense TechnologyChangsha 410073People’s Republic of China Hunan Key Laboratory of Extreme Matter and Applications National University of Defense TechnologyChangsha 410073People’s Republic of China Applied Mechanics Laboratory Department of Engineering MechanicsSchool of AerospaceTsinghua UniversityBeijing 100084People’s Republic of China Institute of Fluid Physics China Academy of Engineering PhysicsMianyangPeople’s Republic of China Department of Material Science and Technology Shanghai Jiao Tong UniversityShanghaiPeople’s Republic of China

Entropy production in quasi-isentropic compression (QIC) is critically important for understanding the properties of materials under extremeconditions. However, the origin and accurate quantification of entropy in this situation remain long-standing challenges. In this work, a framework is established for the quantification of entropy production and partition, and their relation to microstructural change in QIC. Cu50Zr50is taken as a model material, and its compression is simulated by molecular dynamics. On the basis of atomistic simulation-informed physicalproperties and free energy, the thermodynamic path is recovered, and the entropy production and its relation to microstructural change aresuccessfully quantified by the proposed framework. Contrary to intuition, entropy production during QIC of metallic glasses is relativelyinsensitive to the strain rate ˙γ when ˙γ ranges from 7.5 × 10^(8) to 2 × 10^(9)/s, which are values reachable in QIC experiments, with a magnitudeof the order of 10^(−2)kB/atom per GPa. However, when ˙γ is extremely high (>2 × 10^(9)/s), a notable increase in entropy production rate with˙γ is observed. The Taylor–Quinney factor is found to vary with strain but not with strain rate in the simulated regime. It is demonstrated thatentropy production is dominated by the configurational part, compared with the vibrational part. In the rate-insensitive regime, the increase inconfigurational entropy exhibits a linear relation to the Shannon-entropic quantification of microstructural change, and a stretched exponential relation to the Taylor–Quinney factor. The quantification of entropy is expected to provide thermodynamic insights into the fundamentalrelation between microstructure evolution and plastic dissipation.

关键词： entropy metallic regime

A New Ductile Fracture Criterion and Its Application to the Prediction of Forming Limit in Deep Drawing

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Journal of Materials Science & Technology 2003年第Z1期19卷 217-219页

作者： yuying YANG Zhongqi yu Xuechun LI Zhenzhong SUN School of Materials Sci. & Eng. Harbin Institute of Technology Harbin 150001 China School of Materials Sci. & Eng. Harbin Institute of Technology Harbin 150001 China School of Materials Sci. & Eng. Harbin Institute of Technology Harbin 150001 China School of Materials Sci. & Eng. Harbin Institute of Technology Harbin 150001 China

With considering the influence of equivalent plastic strain on void-damage and taking Lemaitre damage equivalent stress as plastic potential, based on continuous damage mechanics theory, a new criterion for ductile fracture is derived. The two key material constants in the criterion are determined by the combination of tension tests with FE (finite element) simulation. On the basis of the values of stress and strain calculated from commercial finite element software, the forming limit in cylindrical deep drawing of annealed aluminum alloy LY12(M) is predicted by means of the new ductile fracture criterion. Experiments verify that the predicted results are in agreement with the experimental ones. Hence, it is reliable to predict the forming limit in deep drawing by means of the new ductile fracture criterion.

关键词： Sheet metal forming, Ductile fracture criterion, FEM, Forming limit

海南岛尖峰岭热带雨林土壤固碳微生物群落特征

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土壤 2024年第1期56卷 64-72页

作者：陈红利赵志忠吴丹余玉莹韩知序霍红义海南师范大学地理与环境科学学院海口571158

采集海南岛尖峰岭地区低地雨林次生林、山地雨林次生林和山地雨林原始林土壤,基于绝对定量PCR和高通量测序技术,探讨了热带雨林土壤中固碳微生物群落结构的多样性与组成及其影响因素。结果表明:固碳微生物的Alpha多样性与基因丰度均表... 详细信息

采集海南岛尖峰岭地区低地雨林次生林、山地雨林次生林和山地雨林原始林土壤,基于绝对定量PCR和高通量测序技术,探讨了热带雨林土壤中固碳微生物群落结构的多样性与组成及其影响因素。结果表明:固碳微生物的Alpha多样性与基因丰度均表现为低地雨林次生林高于山地雨林原始林;尖峰岭热带雨林土壤固碳微生物优势菌门为假单胞菌门(Pseudomonadota,44.28%~70.60%)和放线菌门(Actinomycetota,11.95%~33.73%),优势菌属为慢生根瘤菌属(Bradyrhizobium,11.53%~31.06%)、诺卡氏菌属(Nocardia,4.97%~17.07%)、中慢生根瘤菌属(Mesorhizobium, 4.44%~12.97%)、分枝杆菌属(Mycobacterium, 2.62%~9.20%)、芽绿菌属(Blastochloris,4.34%~10.12%)、固氮弧菌属(Aromatoleum,1.97%~5.39%)、分枝菌酸杆形菌属(Mycolicibacterium,1.71%~3.78%)、固氮螺菌属(Azospirillum,1.97%~2.65%)、Methylibium (1.22%~3.77%),且以兼性自养菌为主。PCoA与LEfSe分析表明,热带雨林3个林型土壤固碳微生物群落存在差异,其标志物种分属放线菌纲、γ-变形菌纲、α-变形菌纲和β-变形菌纲。RDA分析表明,全氮、全磷、有机碳、易氧化有机碳是驱动尖峰岭热带雨林固碳微生物群落差异的重要影响因素。

关键词：热带雨林固碳微生物高通量测序 cbbL基因

冲击加载-卸载-再加载条件下Cr-Ni-Mo钢的层裂损伤

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高压物理学报 2024年第5期38卷 114-123页

作者：洪逸非李绪海吴凤超张昭国张建陈森王媛俞宇颖胡建波武汉理工大学材料复合新技术国家重点实验室湖北武汉430070 中国工程物理研究院流体物理研究所四川绵阳621999

基于一级轻气炮加载技术,利用不同类型的多层复合飞片,实现了冲击加载-卸载-再加载路径,结合回收表征以及一维流体力学模拟,对Cr-Ni-Mo钢在冲击加载-卸载-再加载路径下的层裂损伤行为进行了深入研究。结果表明,在冲击加载-卸载-再加载... 详细信息

基于一级轻气炮加载技术,利用不同类型的多层复合飞片,实现了冲击加载-卸载-再加载路径,结合回收表征以及一维流体力学模拟,对Cr-Ni-Mo钢在冲击加载-卸载-再加载路径下的层裂损伤行为进行了深入研究。结果表明,在冲击加载-卸载-再加载路径下,层裂面会重新闭合并形成微损伤带,而孔洞位置仍然位于原奥氏体边界和板条群边界处,裂纹仍保持穿晶+沿晶的混合断裂模式。此外,第1层飞片与样品之间存在的较大阻抗差异会导致自由面速度中的再加载信号缺失。这些发现为深入理解Cr-Ni-Mo钢在复杂加载路径下的层裂行为提供了重要参考。

关键词： Cr-Ni-Mo钢层裂冲击加载再加载加载路径

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论清初遗民小说中的人文思潮

明清小说研究 2023年第1期 94-106页

作者：杨剑兵郁玉英汕头大学文学院

清初的人文思潮主要包括经世致用的学术思潮、理欲统一的社会思潮和注重社会功用的文学思潮。这些思潮对清初文学产生重要影响,特别是对清初遗民小说产生重要影响。同时,清初遗民小说较为系统地、充分地反映与体现这些思潮,主要表现在... 详细信息

清初的人文思潮主要包括经世致用的学术思潮、理欲统一的社会思潮和注重社会功用的文学思潮。这些思潮对清初文学产生重要影响,特别是对清初遗民小说产生重要影响。同时,清初遗民小说较为系统地、充分地反映与体现这些思潮,主要表现在小说开始出现实学思潮的文学叙事、理存于欲的文学书写、文学教化色彩渐趋浓厚。

关键词：学术思潮社会思潮文学思潮清初遗民小说

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李闯故事在清初章回小说中的嬗变

明清小说研究 2021年第4期 52-68页

作者：杨剑兵郁玉英汕头大学文学院

清初以描写李闯故事为主要内容的章回体小说计有四部,亦即《新编剿闯通俗小说》《新世弘勋》《樵史通俗演义》《铁冠图全传》。它们经历了采录、反思、重构三个阶段的嬗变。其中《新编剿闯通俗小说》《新世弘勋》为采录阶段,《樵史通俗... 详细信息

清初以描写李闯故事为主要内容的章回体小说计有四部,亦即《新编剿闯通俗小说》《新世弘勋》《樵史通俗演义》《铁冠图全传》。它们经历了采录、反思、重构三个阶段的嬗变。其中《新编剿闯通俗小说》《新世弘勋》为采录阶段,《樵史通俗演义》为反思阶段,《铁冠图全传》为重构阶段。它们的主要嬗变规律包括创作内容上渐趋丰富,创作方法上渐趋小说化,创作心态上遗民意识渐趋淡化。

关键词：李闯故事李自成遗民意识嬗变

Life’s Essential 8 and risk of non-communicable chronic diseases:Outcome-wide analyses

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Chinese Medical Journal 2024年第13期137卷 1553-1562页

作者： yuetian yu Ying Sun yuefeng yu yuying Wang Chi Chen Xiao Tan Yingli Lu Ningjian Wang Institute and Department of Endocrinology and Metabolism Shanghai Ninth People’s HospitalShanghai JiaoTong University School of MedicineShanghai 200011China School of Public Health Zhejiang UniversityHangzhou 310058ZhejiangChina Department of Medical Sciences Uppsala UniversityUppsala 75185Sweden

Background:Life’s Simple 7,the former construct of cardiovascular health(CVH)has been used to evaluate adverse non-communicable chronic diseases(NCDs).However,some flaws have been recognized in recent years and Life’s Essential 8 has been *** this study,we aimed to analyze the association between CVH defined by Life’s Essential 8 and risk of 44 common NCDs and further estimate the population attributable fractions(PAFs)of low-moderate CVH scores in the 44 ***:In the UK Biobank,170,726 participants free of 44 common NCDs at baseline were *** Life’s Essential 8 composite measure consists of four health behaviours(diet,physical activity,nicotine exposure,and sleep)and four health factors(body mass index,non-high density lipoprotein cholesterol,blood glucose,and blood pressure),and the maximum CVH score was 100 *** score was categorized into low,moderate,and high *** were followed up for 44 NCDs diagnosis across 10 human system disorders according to the International Classification of Diseases 10th edition(ICD-10)code using linkage to national health records until *** proportional hazard models were used in this *** hazard ratios(HRs)and PAFs of 44 NCDs associated with CVH score were ***:During the median follow-up of 10.85 years,58,889 incident NCD cases were *** linear dose-response associations were found between higher CVH score and lower risk of 25(56.8%)of 44 ***-moderate CVH(<80 points)score accounted for the largest proportion of incident cases in diabetes(PAF:80.3%),followed by gout(59.6%),sleep disorder(55.6%),chronic liver disease(45.9%),chronic kidney disease(40.9%),ischemic heart disease(40.8%),chronic obstructive pulmonary disease(40.0%),endometrium cancer(35.8%),lung cancer(34.0%),and heart failure(34.0%)as the top *** the eight modifiable factors,overweight/obesity explained the largest number of cases of incident NCDs in endocrine,nutritional,and me

关键词： Life’s Essential 8 Cardiovascular risk score Non-communicable chronic disease Population health management Cohort analysis Healthy lifestyle UK Biobank

小秦岭熊耳群火山岩锆石U-Pb年龄及其地球化学特征

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地质科技情报 2016年第5期35卷 1-8页

作者：呼延钰莹路玉西北大学地质系西安710069 西北大学大陆动力学国家重点实验室西安710069 中国石油大学(北京) 北京102249 中国地质大学(北京) 北京100083

熊耳群火山岩是华北陆块结晶基底形成后规模最大、涉及范围最广的火山活动产物,其时代归属一直存在争议。研究获得小秦岭地区熊耳群火山岩LA-ICP-MS锆石207Pb/206Pb年龄加权平均值为（1 810±41）Ma（MSWD=0.16）。综合河南和山西等地... 详细信息

熊耳群火山岩是华北陆块结晶基底形成后规模最大、涉及范围最广的火山活动产物,其时代归属一直存在争议。研究获得小秦岭地区熊耳群火山岩LA-ICP-MS锆石207Pb/206Pb年龄加权平均值为（1 810±41）Ma（MSWD=0.16）。综合河南和山西等地熊耳群火山岩测年结果,笔者认为熊耳群火山岩的时限很可能为1.81~1.75Ga,属于哥伦比亚超大陆碰撞作用晚期。该套火山岩主要由玄武安山岩和安山岩组成,具有较高的K_2O、FeO和低的A1_2O_3、MgO、CaO含量,反映岩石具有高钾弱碱性的特点;岩石的稀土元素总量高,REE分配曲线呈右倾型,具轻微Eu负异常;富集大离子亲石元素（K、Rb、Ba）,亏损高场强元素（Nb、Ta、Ti）。火山岩具有与＂岛弧型＂相似的稀土和微量元素特征,为典型的俯冲成因类型。

关键词：熊耳群火山岩 U-Pb锆石华北克拉通哥伦比亚超大陆

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论朱敦儒的文人风致

中州学刊 2006年第2期 192-197页

作者：郁玉英王兆鹏武汉大学文学院湖北武汉430072

朱敦儒向来以“神仙风致”为人所知,然而“世外希真”并非全然一派超然世外之风,而是清爽仙风和自傲享乐的复合。在特定历史条件下,这是一种融合时代共性和个体气质的文人风致,具体表现为坚持自我理想人格的人生态度、追求清雅旷逸之韵... 详细信息

朱敦儒向来以“神仙风致”为人所知,然而“世外希真”并非全然一派超然世外之风,而是清爽仙风和自傲享乐的复合。在特定历史条件下,这是一种融合时代共性和个体气质的文人风致,具体表现为坚持自我理想人格的人生态度、追求清雅旷逸之韵的审美理想以及隐于山水云壑、醉于诗酒风流的生活方式。这些表面上互不关联的理想却有机地统一于一位古代文士对自由生命的向往和追求之中,一个真实的人物通过自己的生活和创作实践表现出一种充满诗意的人生境界。

关键词：朱敦儒《樵歌》文人风致人生境界