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基于HyperMesh应变速率对零件材料性能影响分析

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机械设计与制造 2024年第6期400卷 242-245页

作者：王彦婷刘海娜王凯黄河交通学院河南焦作454950

车身在碰撞过程中,不同位置零件材料发生变形的应变速率差异较大,这对材料的性能产生重要影响。选取汽车结构件常用材料HC300LA为研究对象,获取材料在不同应变速率下的高速拉伸性能;通过断口形貌和组织变化的观察,对材料不同应变速率下... 详细信息

车身在碰撞过程中,不同位置零件材料发生变形的应变速率差异较大,这对材料的性能产生重要影响。选取汽车结构件常用材料HC300LA为研究对象,获取材料在不同应变速率下的高速拉伸性能;通过断口形貌和组织变化的观察,对材料不同应变速率下的特性进行分析;获取材料吸能和韧窝尺寸等与应变速率之间的关系;基于Johnson-Cook模型建立材料的动态力学性能本构方程;基于HyperMesh搭建拉伸试样仿真分析模型,通过施加位移,获取整个过程力-位移曲线,并与试验测试结果进行对比,以此对材料应变速率相关的本构模型进行验证。对比分析结果可知:所研究的材料HC300LA具有较强的正应变速率敏感性,力学性能呈现增强的趋势;材料的断裂吸能能力和断口韧窝变得更大更深,并且韧窝的分布更加密集;考虑应变速率影响的材料本构模型,拉伸过程仿真分析与试验测试结果的最大力和最大位移保持基本一致,误差控制在4%以内,而且力-位移的变化趋势保持一致;分析结果表明,在碰撞分析时,不能忽略应变速率对材料的影响;同时表明前述分析模型是可靠的,为此类研究提供重要参考。

关键词：车身零件应变速率力学性能本构模型

Preliminary study on strontium-rich characteristics of shallow groundwater in Dingtao Area,China

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Journal of Groundwater Science and Engineering 2020年第3期8卷 244-258页

作者： CAO yan-ling SONG Liang LIU Lian ZHU Wen-feng CUI Su wang yan-ting GUO Peng Institute of Geology and Mineral Resources of Shandong Province Jinan 250014China

Based on the analysis of element correlation,the Gibbs diagram,hydro-geochemical ion ratios,isoline maps of groundwater and soil,and change patterns of strontium content after normalization,the study examines water-rock interaction of shallow groundwater in Dingtao area.The results suggest that strontium in the study area mainly comes from waterrock interactions,and the strata interacting with groundwater are the top of Quaternary and Neogene.The element correlation analysis shows that the formation of strontium-rich groundwater is sufficiently affected by sulfate and carbonate.The Gibbs diagram suggests that the chemical composition of groundwater is mainly influenced by water-rock interactions,accompanied by evaporation crystallization.c(Ca2++Mg2+)/c(HCO3-+SO42-)reflects that the main reactions in the groundwater system is weathering dissolution of carbonate and sulfate,and ion exchange takes place.c(Na+)/c(Cl-)indicates that Na+in groundwater may have waterrock interactions with rocks it flows through.c(Cl-)/c(Ca2+)indicates that the hydrodynamic condition in the pumping well is poor and the water circulation is slow.The study examines the macro isoline map change patterns,correlation curves of change of strontium content in groundwater and shallow soil,and correlation curves of change of strontium content in groundwater,shallow soil,and deep soil.The results suggest that the strontium content in the study area has the same change pattern in groundwater and in soil,which further indicates that strontium in the study area comes from water-rock interactions.

关键词： Strontium Water-rock interaction Evaporation concentration Element correlation Gibbs diagram Ion ratio

硬岩地层超深基坑桩锚支护体系受力与变形特性实测分析

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科学技术与工程 2024年第15期24卷 6398-6404页

作者：郝增明闫楠刘作岩银吉超孙培富王砚廷白晓宇青岛理工大学土木工程学院青岛266520 青岛中建联合集团有限公司青岛266100

为探究硬岩地层超深基坑桩锚支护体系随基坑开挖的受力与变形演化规律,依托于崂山公卫中心基坑支护工程,对南侧支护完成区域基坑的预应力锚索轴力、基坑水平和竖向位移进行了实时监测,分析桩锚支护体系在该地质条件下的力学性能,探讨锚... 详细信息

为探究硬岩地层超深基坑桩锚支护体系随基坑开挖的受力与变形演化规律,依托于崂山公卫中心基坑支护工程,对南侧支护完成区域基坑的预应力锚索轴力、基坑水平和竖向位移进行了实时监测,分析桩锚支护体系在该地质条件下的力学性能,探讨锚索轴力急速下降与基坑水平位移增大的影响因素。研究表明:预应力锚索轴力持续、急速的下降与基坑紧邻原状山体的土压力和北侧后挖区域的持续施工有关,工程中采取预应力锚索2次补偿张拉适用效果良好;基坑最大水平位移为19.98 mm,最大竖向位移为12.11 mm,南侧支护完成区域基坑支护体系的变形受后续施工区域的影响明显;桩锚支护体系在硬岩及土岩二元地层超深基坑中具有较好的适用性和可靠性。类似工程支护结构设计应重视周边地质环境、邻近区域持续施工等因素的影响。

关键词：超深基坑硬岩地层桩锚支护锚索轴力基坑变形

青海省推广禾豆混播技术的重要意义、现实困境及路径指引

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青海草业 2024年第1期33卷 30-33,43页

作者：王廷艳袁桂英张铭杨学贵青海省饲草料技术推广站青海西宁810001

在创建“青海绿色有机农畜产品输出地”和开展化肥农药减量增效行动的大背景下,对如何增加单位面积耕地中饲草作物产量,提高饲草产品的品质提出了新的挑战。禾豆混播技术作为一种高效的种植模式具有重要价值与意义。通过分析总结近年来... 详细信息

在创建“青海绿色有机农畜产品输出地”和开展化肥农药减量增效行动的大背景下,对如何增加单位面积耕地中饲草作物产量,提高饲草产品的品质提出了新的挑战。禾豆混播技术作为一种高效的种植模式具有重要价值与意义。通过分析总结近年来青海省推广禾豆混播技术的现实意义,剖析当前存在的现实困境,提出几点解决路径,以期为加快该项技术的快速推广提供理论参考与决策依据。

关键词：青海省禾豆混播技术推广价值路径指引

Comparative study of notional passive in English and Chinese

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Sino-US English Teaching 2007年第12期4卷 47-52页

作者： wang yan-ting LI Xiao-feng English Department PLA Foreign Languages University Luoyang 471003 China Eurasia Department PLA Foreign Languages University Luoyang 471003 China

Bibliography on Small Systems: Nonequilibrium Phenomena and Anomalous Behavior

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Communications in Theoretical Physics 2014年第10期61卷 631-633页

作者： LIU Fei Lamberto Rondoni TANG Lei-Han ZHOU Hai-Jun wang yan-ting

The workshop and satellite conference held in July 2013 at the Kavli Institute for Theoretical Physics China(KITPC)of the Chinese Academy of Sciences(CAS)brought together experts of a variety of different fields,and constituted a unique opportunity to share ideas and breed new ones in a strongly interdisciplinary fashion.At the same time,the breadth of the scope of these two meetings was so wide that the need for a collection of reference

关键词： opportunity collection workshop fashion breed stochastic fluctuation deviation mathematics earlier

Preface to Special Issue on Small Systems: Nonequilibrium Phenomena and Anomalous Behavior

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Communications in Theoretical Physics 2014年第10期61卷 441-442页

作者： LIU Fei Lamberto Rondoni TANG Lei-Han wang yan-ting ZHOU Hai-Jun

In July 2013,the Kavli Institute for Theoretical Physics China(KITPC)at the Chinese Academy of Sciences(CAS)hosted two important events in the field of Nonequilibrium Statistical Physics and its applications to modern biology and nanotechnology.The first,entitled"Non-Equilibrium Phenomena,Spin Glasses,and Algorithms",held from 1 to5 July 2013,was the Beijing Satellite Meeting of STATPHYS 25.The second,entitled"Small

关键词： entitled nanotechnology Australia relaxation challenging participation interested viewpoint concerning grateful

Brucine N-oxide reduces ethanol intake and preference in alcohol-preferring Fawn-Hooded rats

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中国药理学与毒理学杂志 2017年第5期31卷 479-480页

作者： LIANG Jian-hui WEI Shou-peng LI Yu-ling GONG Qi wang yan-ting LIANG Hui LIU Qing ZHANG Han-ting CHEN Feng Andrew J LOWRENCE Department of Molecular and Cellular Pharmacology School of Pharmaceutical Sciences Department of Pharmacology School of Basic Medicine SciencesPeking University Institute of Psycopharmacology Central Institute of Mental HealthUniversity of Heidelberg Departments of Behavioral Medicine & Psychiatry and Physiology& Pharmacology West Virginia University Health Sciences Center The Florey Institute of Neuroscience and Mental Health University of Melbourne

OBJECTIVE The alcoholism-related social problems have burdened the public health heavily.A better therapy for alcohol dependence as a chronic brain disease is highly required and interests the scientists worldwide. Our group has focused on screening the right drug with low toxicity and a sound curative effect from traditional Chinese medicine. METHODS Alcohol-preferring Fawn-Hooded(FH/Wjd) rat was used as an animal model of alcoholism to evaluate the effects of brucine N-oxide(BNO),an alkoloid naturally existing in the seeds of Strychnos nux-vomica L,on the alcohol-drinking behaviors.Furthermore,its adverse action and toxicity were investigated. RESULTS Treatment with BNO at the doses of 30,50 and 70 mg · kg^(-1)reduced the voluntary alcohol consumption and preference dosedependently and selectively without altering their water intake,total fluid intake,food consumption,body weight as well as sucrose preference. Remarkably,70 mg·kg^(-1)of BNO did suppress the deprivationinduced elevation of alcohol ingestion. Moreover,BNO used at the same doses as above had no influence on locomotion in an open field test and could not result in the place preference effect. CONCLUSION Taken together,BNO is of some significant pharmacological profiles to inhibit symptoms of alcohol dependence with high safety,and thence may be a potential pharmacotherapy.

关键词： brucine N-oxide ethanol

Gastric cancer secreted miR 214-3p inhibits the anti-angiogenesis effect of apatinib by suppressing ferroptosis in vascular endothelial cells

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Oncology Research 2024年第3期32卷 489-502页

作者： WEIXUE wang TONGTONG wang yan ZHANG ting DENG HAIyanG ZHANG YI BA Department of GI Medical Oncology Tanjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerTianjin's Clinical Research Center for CancerTianjin Key Iaboratory of Digestive CancerKey Laboratory of Cancer Prevention and TherapyTianjin300060China

Diferent from necrosis,apoptosis,autophagy and other forms of cell death,ferroptosis is a mechanism that catalyzes lipid peroxidation of polyunsaturated ftty acids under the action of iron divalent or lipoxygenase,leading to cell death.Apatinib is currently used in the third line standard treatment of advanced gastric cancer,targeting the anti-angiogenesis pathway.However,Apatinib mediated ferroptosis in vascular endothelial cells has not been reported yet.Tumor.secreted exosomes can be taken up into target cells to regulate tumor development,but the mechanism related to vascular endothelial cell ferroptosis has not yet been discovered.Here,we show that exosomes secreted by gastric cancer cells carry miR-214.3p into vascular endothelial cells and directdy target zinc finger protein A20 to negatively regulate ACSL4,a key enzyme of lipid peroxidation during frroptosis thereby inhibiting ferroptosis in vascular endothelial cells and reducing the eficiency of Apatinib.In conclusion,inhibition of miR-214-3p can increase the sensitivity of vascular endothelial cells to Apatinib,thereby promoting the antiangiogenic efect of Apatinib,suggesting a potential combination therapy for advanced gastric cancer.

关键词： Cellular ferroptosis Exosome Tyrosine kinase inhibitor Gastrointestinal tumors miRNA