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藏东贡觉地区地应力场分布特征及影响因素研究

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地球物理学进展 2024年第3期39卷 938-950页

作者：廖昕吕改杰陈仕阔王虎赵晓彦黄涛西南交通大学地球科学与环境工程学院成都611756 四川省环青藏高原交通廊道地质灾害生态化防治工程技术研究中心成都611756 中国铁路设计集团有限公司天津300142

藏东贡觉地区位于金沙江断裂带北段,经历了复杂的地质构造演化.本文基于水压致裂法地应力实测数据,通过计算评价主应力量值、侧压力系数、主应力方位及构造应力等地应力特征参数,分析了贡觉地区现今地应力场分布规律及其影响因素.结果表... 详细信息

藏东贡觉地区位于金沙江断裂带北段,经历了复杂的地质构造演化.本文基于水压致裂法地应力实测数据,通过计算评价主应力量值、侧压力系数、主应力方位及构造应力等地应力特征参数,分析了贡觉地区现今地应力场分布规律及其影响因素.结果表明:藏东贡觉地区实测主应力随深度增加而增大,浅部(m)数据较为离散,深部(>500 m)数据呈线性分布,表现为S_(v)>S_(H)>S_(h),水平主应力随深度变化梯度低于背景地块相应梯度水平;实测最大水平主应力优势方位为NNE向,与区域应力场优势方位NE—NEE向呈现逆时针偏转;通过对研究区侧压力系数、水平应力比、剪应力相对大小(μ_(m))以及Sheorey模型分析得出,研究区水平构造应力积累程度和活动程度均较低,区内字嘎寺—德钦断层处于稳定状态.研究区地应力场影响因素主要为重力作用、地形特征以及构造作用.岩体自重对地应力的影响主要遵循静水压力规律;地形地貌的影响主要体现为浅部(m)水平向主应力值较离散,在深切峡谷区侧压力系数由谷底至坡顶逐渐减小;构造作用对研究区地应力场的影响主要集中在字嘎寺—德钦断层两侧一定范围内,表现为局部地应力场的主应力方位偏转及主应力量值异常.研究结果可为藏东贡觉地区及类似地质环境区域稳定性评价以及地下工程选址建设提供理论依据.

关键词：贡觉地区地应力场分布特征地形特征构造应力

Using Symbolic Computation to Exactly Solve the Integrable Broer-Kaup Equations in （2＋1）-Dimensional Spaces

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Communications in Theoretical Physics 2005年第4期43卷 585-590页

作者： CHENJing XIEFu-Ding lüZhuo-Sheng DepartmentofComputerScience LiaoningNormalUniversityDalian116029China Keylaboratoryofmathematicsmechanization InstituteofSystemsSciencesAcademyofMathematicsandSystemsSciencestheChineseAcademyofSciencesBeijing100080China

The extended tanh method is further improved by generalizing the Riccati equation and introducing its twenty seven new solutions. As its application, the (2+ 1)-dimensional Broer-Kaup equation is investigated and then its fifty four non-travelling wave solutions have been obtained. The results reported in this paper show that this method is more powerful than those, such as tanh method, extended tanh method, modified extended tanh method and Riccati equation expansion method introduced in previous literatures.

关键词： BK equations symbolic computation non-travelling wave solution

modeling mechanistic responses in asphalt pavements under three-dimensional tire-pavement contact pressure

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Journal of Central South University 2011年第1期18卷 250-258页

作者：胡小弟 l.F.WAlUBITA Texas Transportation Institute Texas A&M University SystemCollege StationTexas 77840-3135USA Transportation Research Center Wuhan Institute of TechnologyWuhan 430073China

A three dimensional finite element program incorporating actually measured vertical tire-pavement contact pressure(TPCP) was utilized for modeling the mechanistic responses in asphalt concrete(AC) layers by simulating various vehicle motions:stationary and non-stationary(*** acceleration or deceleration mode).Analysis of the results indicated the following items.1) It is critical to use the vertical TPCP as the design control criteria for the tensile strains at the bottom of the AC layer when the base layer modulus is lower in magnitude(e.g.≤400 mPa);however,when the base layer modulus is higher in magnitude(e.g.≥7 000 mPa),the horizontal TPCP and the tensile strains in the X-direction at the surface of the AC layer should also be considered as part of the design response criteria.2) The definition of "overload" needs to be revised to include tire pressure over-inflation,i.e.,a vehicle should be considered to be overloaded if the wheel load exceeds the specification and/or the tire inflation pressure is higher than the specification.3) light trucks have more structural impact on the strain responses and pavement design when the thickness of the surfacing AC layer is thinner(e.g.≤50 mm).4) The acceleration of a vehicle does not significantly impact the AC surface distresses such as rutting at the top of the upgrade slopes or intersections;however,vehicle deceleration can dramatically induce horizontal shear strains and consequently,aggravate shoving and rutting problems at the highway ***,these factors should be taken into account during mechanistic stress-strain modeling and structural design of asphalt pavements.

关键词： asphalt pavement tire-pavement contact pressure vehicle acceleration mechanistic response three-dimensional finiteelement

First-principles Study of Point Defects in Stoichiometric and Non-stoichiometric Y_4Al_2O_9

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Journal of materials Science & Technology 2013年第12期29卷 1161-1165页

作者： Z.li B.liu J.m.Wang l.C.Sun J.Y.Wang Y.C.Zhou Z.J.Hu High-performance Ceramics Division Shenyang National Laboratory for Materials ScienceInstitute of Metal ResearchChinese Academy of Sciences Aerospace Research Institute of materials and Processing Technology

By using the first-principles calculation, we studied the mechanisms of point defects in Y4AI209 （YAm）, a promising ternary oxide with excellent optical and thermal properties. It is found that the predominant native defect species is closely dependent on the chemical potentials of each constituent. In the case of O-rich condition, the oxygen interstitial has the very low defect formation energy, followed by the anti-site defects and AI vacancy; in the case of AI-rich condition, the oxygen vacancy yields the lowest defect formation energy, followed by the anti-site defects and AI interstitial. The present result shows that in all the possible chemical potential ranges, anti-site defects have relatively low defect formation energy and might exist in high concentration in YAm. Furthermore, AIy anti-site has relatively lower defect formation energy than the YAt anti- site throughout. The behaviors of defect complexes under non-stoichiometric condition, such as the AI203 or Y203 excess, are also investigated. The results provide helpful guide to optimize the experimental synthesizing of YAm.

关键词： Ternary Y-AI-O oxide Defect formation energy Chemical potential

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橄榄石集合体扭转大变形实验研究

岩石学报 2008年第6期24卷 1411-1416页

作者：赵永红綦超李杨 m. Zimmerman D. l. Kohlstedt 北京大学地球物理学系北京100871 美国明尼苏达大学地质与地球物理系mN55455

对(mg_(0.5),Fe_(0.5))_2SiO_4和(mg_(0.7)、Fe_(0.3))_2SiO_4橄榄石集合体进行了高温高压扭转大变形实验研究。试验在高精度和高分辨率 Paterson 气体介质变形试验机上进行,试验温度为1473K,围压为300mPa,应变率为10^(-4)～10^(-5)S^(-1),剪切应力为82～124mPa,剪切应变为～400%,将变形后试件沿轴向切开进行了显微结构分析,确定了不同纵截面上橄榄石的颗粒尺寸。由蠕变数据拟合出的流动律中,应力指数为与三轴压缩实验给出的应力指数吻合。利用 EBSD 方法分别对变形前后试件中橄榄石的晶格最优取向(lPO)进行了测定。在富铁橄榄石样品中观测到的最优晶格取向表明滑动属于(okl)[100]滑动系统。这个结果与 Bystricky 等人在 Fo_(90)种观测到的最优晶格取向特征是一致的。

关键词：橄榄石集合体高温高压扭转大变形晶格最优取向(lPO) 实验研究

Acetaminophen and zinc phosphide for lethal management of invasive lizards Ctenosaura similis

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Current Zoology 2011年第5期57卷 625-629页

作者： michael l. AVERY John D. EISEmANN Kandy l. KEACHER Peter J. SAVARIE United States Department of Agriculture Wildlife Services National Wildlife Research Center Florida Field Station 2820 East University Avenue Gainesville FL 32641 USA United States Department of Agriculture Wildlife Services National Wildlife Research Center Ft. Collins CO 80225 USA

Reducing populations of invasive lizards through trapping and shooting is feasible in many cases but effective inte-grated management relies on a variety of tools, including toxicants. In Florida, using wild-caught non-native black spiny-tailed iguanas Ctenosaura similis, we screened acetaminophen and zinc phosphide to determine their suitability for effective population management of this prolific invasive species. Of the animals that received acetaminophen, none died except at the highest test dose, 240 mg per lizard, which is not practical for field use. Zinc phosphide produced 100% mortality at dose levels as little as 25 mg per lizard, equivalent to about 0.5% in bait which is lower than currently used in commercial baits for commensal rodent con-trol. We conclude that zinc phosphide has potential as a useful tool for reducing populations of invasive lizards such as the black spiny-tailed iguana provided target-selective delivery methods are developed [Current Zoology 57 （5）： 625~529, 2011].

关键词： Acetaminophen Black spiny-tailed iguana Ctenosaura similis Florida Invasive Zinc phosphide

lHCb gets closer to discovering the second doubly charmed baryon

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Science China(Physics,mechanics & Astronomy) 2020年第2期63卷 25-26页

作者： marek Karliner Jonathan l.Rosner School of Physics and Astronomy Tel Aviv UniversityTel Aviv 69978Israel Enrico Fermi Institute and Department of Physics University of ChicagoChicagoIL 60637USA

Recently the lHCb Collaboration [1] published the results of a search for the doubly charmed baryon ■. No significant signal is seen in the mass range from 3.4 to3.8 Ge V. To put this result in context, the ■baryon was seen by lHCb in decay modes ΛcK-π^+π^+[2](2017) and ■^+cπ^+[3](2018). The weighted average of the ■^++cc mass is 3621.24±0.65 (stat.)±0.31 (syst.) meV [3].

关键词： doubly closer lHCb

原花青素对体外培养牛卵泡颗粒细胞增殖及其类固醇合成与分泌功能的影响

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西北农林科技大学学报（自然科学版） 2024年第6期52卷 11-19页

作者：杨小峰党文庆秦小伟王锴吕丽华忻州师范学院生物系山西忻州034000 山西农业大学动物科学学院山西太谷030801

【目的】探究原花青素(proanthocyanidins,PC)对体外培养的牛卵泡颗粒细胞(granulosa cells,GCs)增殖及其类固醇合成与分泌功能的影响。【方法】采集性成熟荷斯坦奶牛卵巢组织,分离卵泡GCs,使用免疫荧光对其进行鉴定。用不同质量浓度(10... 详细信息

【目的】探究原花青素(proanthocyanidins,PC)对体外培养的牛卵泡颗粒细胞(granulosa cells,GCs)增殖及其类固醇合成与分泌功能的影响。【方法】采集性成熟荷斯坦奶牛卵巢组织,分离卵泡GCs,使用免疫荧光对其进行鉴定。用不同质量浓度(10,30,50,70和90μg/ml)的PC对牛卵泡GCs作用不同时间(12,24和48 h)后,测定GCs存活率。以β-actin为内参基因,采用实时荧光定量PCR(qRT-PCR)检测10,50和90μg/ml PC对牛卵泡GCs周期相关基因(CCND1和CCND2)、凋亡相关基因(caspase-3、caspase-9和Bim)以及类固醇激素合成相关基因(CYP19A1、CYP11A1、STAR和3β-HSD)相对表达量的影响,并检测培养上清液中类固醇激素(雌二醇(E_(2))和孕酮(P_(4)))的浓度。【结果】分离获得了纯度较高的牛卵泡GCs。当PC质量浓度为50μg/ml且培养24 h时,牛卵泡GCs的存活率最高。当PC质量浓度为50μg/ml时,牛卵泡GCs周期相关基因CCND1和CCND2相对表达量均极显著升高(Pm相对表达量显著降低(Pml时,牛卵泡GCs凋亡相关基因caspase-3的相对表达量显著降低(Pml时,E_(2)浓度显著增加(Pml PC通过促进牛卵泡GCs周期相关基因的表达和抑制凋亡相关基因的表达而促进牛卵泡GCs的增殖。10~90μg/ml PC通过促进类固醇激素合成相关基因的表达而促进了牛卵泡GCs合成和分泌类固醇激素,进而影响牛卵泡GCs类固醇激素合成与分泌功能。

关键词：原花青素牛卵泡颗粒细胞细胞增殖细胞凋亡类固醇

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Synaptopathy in CHmP2B frontotemporal dementia highlights the synaptic vesicle cycle as a therapeutic target

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Neural Regeneration Research 2023年第2期18卷 315-316页

作者： miranda Robbins Emma l.Clayton mRC laboratory of molecular Biology Department of Zoology University of CambridgeCambridgeUK UK Dementia Research Institute at King’s College london Department of Basic and Clinical Neuroscience Institute of PsychiatryPsychology and NeuroscienceKing’s College LondonMaurice Wohl Clinical Neuroscience InstituteLondonUK

Amyotrophic lateral sclerosis(AlS)and frontotemporal dementia(FTD)are both devastating neurodegenerative *** affecting different regions of the nervous system(FTD affecting primarily the frontal and temporal lobes,whilst AlS presents with motor neuron loss),there is significant overlap between these conditions in terms of genetics,pathology,and disease mechanisms,and they are therefore often grouped as a spectrum of symptoms under the heading FTD/AlS(Abramzon et al.,2020).Significantly,there is currently no cure for AlS or ***,recent mechanistic insight points to a novel pathway to target for potential therapeutic intervention.

关键词： therapeutic pathology