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1.
通过野外详细地质路线调查,结合各种尺度的构造研究和变形分析,确定了秦岭群南缘及丹凤群内韧性剪切带的存在及其分布范围。提出了该韧性剪切带的几何学和运动学特征及变形机制,估算了韧性剪切带形成时古差应力值,并对该韧性剪切带形成时代及形成模式进行了探讨。  相似文献   

2.
采用万能实验机对Ti35.37Cu45.11Ni8.88Zr10.64大块金属玻璃进行室温压缩实验,研究了锯齿流变应力降对剪切带扩展的影响。实验结果表明:高塑性的大块金属玻璃压缩后表面呈现密集剪切带,且锯齿流变呈现非周期性。根据锯齿流变的变化,对剪切带的形成与扩展分4个区域进行研究,结果表明:区域Ⅰ为大量的剪切带萌生并快速长大的过程;区域Ⅱ为剪切带的稳定扩展,并且扩展的幅度大致相等;区域Ⅲ为剪切带的相互交割与滑移;区域IV为大部分剪切带扩展到整个样品,仅有少量剪切带进行缓慢扩展。  相似文献   

3.
用金相显微镜(OM)和透射电子显微镜(TEM)对2519A-T87铝合金靶材弹坑周围的高速冲击特征组织进行了观察分析。在OM下观察分析发现弹坑周围形成了变形带和绝热剪切带,裂纹在绝热剪切带内萌发和扩展。TEM下观察分析发现变形带内为微带组织,绝热剪切带内是动态再结晶组织。位错在微观组织演化过程中起到了重要作用。显微硬度测试结果表明,绝热剪切带的硬度值远远低于基体。  相似文献   

4.
湖北青峰断裂为一韧性剪切带。对其几何学、运动学和动力学进行系统研究表明,变形机制为简单剪切机制,形成时的构造差异应力平均值为137.92MPa,应变速率为6.713×10-15s-1。文章还讨论了断裂带的变形环境。  相似文献   

5.
基于数字照相的砂土剪切变形模式的试验研究   总被引:6,自引:0,他引:6  
利用自行研制的数字照相量测软件包Photolnfor和自行设计的大型剪切试验装置,在不同围压下,对砂土的剪切变形模式以及土体变形局部化的发生、发展和演变过程进行了全面观测.结果表明:砂土变形区域呈纺锤型,由多条曲线形大变形带和带间小变形区组成,不同围压下的剪切变形模式基本相近;土体最终形成的剪切带与初期发生的局部变形带并不完全重合;土体剪切变形可分为初期全域快速弹性变形、中期局部区域塑性变形与后期剪切带内集中塑性变形三个阶段.  相似文献   

6.
采用分离式霍普金森压杆技术和一种新型限位试验方法对TC6钛合金进行了动态压缩试验,使用光学显微镜、扫描电子显微镜分析了TC6钛合金变形到不同应变量时所产生绝热剪切带的微观形貌,通过与宏观力学响应相对应,研究了TC6钛合金圆柱试样中绝热剪切带刚萌生时对应的临界应变及绝热剪切带的扩展速率.结果表明:在高应变率下,材料绝热剪切带的形成是一个由萌生、扩展、完全发展组成的过程;在应变率为2.5×10~3s~(-1)时,TC6钛合金动态压缩时绝热剪切带萌生时对应的临界应变为0.126 9,其扩展速率大约为87 m/s.  相似文献   

7.
商南-商城断裂带中段的韧性剪切带是由多条糜棱岩带及其所夹的变质岩块体组成的大型韧性剪切带。它是以简单剪切为主要变形机制的、于绿片岩相温压条件下形成的韧性剪切带。剪切带内糜棱岩的塑性变形和恢复重结晶作用强烈。糜棱叶理产状多较陡倾,a线理近水平,表明为走滑断裂。大量不对称旋转构造指示该剪切带早期为左行剪切,后期在不同地段又叠加上程度不同的右行剪切  相似文献   

8.
肥东低角度韧性剪切带紧邻郯庐断裂带巨大的近直立的左行平移韧性剪切带发育,其岩石变质变形特征具有韧性剪切带的一般特征,即越靠近剪切带内侧,岩石变质变形程度越强,远离韧性剪切带,岩石变质变形强度越弱。低角度韧性剪切带内超糜棱岩变形强烈,变质相可达到角闪岩相,其变质变形程度与直立的郯庐断裂带内超糜棱变质变形程度类似,两者在形成环境和成因类型上统一,具有大陆岩石圈被高角度韧性剪切带切割并沿低角度韧性剪切带逆冲推覆的形成机制。  相似文献   

9.
通过数字图像相关方法从实验上观察到内生晶体复合材料在微米尺度应变场的演化与剪切带行为,并结合有限元,模拟了非晶合金复合材料的变形,给出了应力应变场的分布,分析了两相在变形中的作用.实验与有限元结果表明,在宏观弹性段内,晶体相会优先发生塑性变形,而后在界面形成应变集中,逐渐向周围扩展;随着加载的进行,材料内部形成变形局部化剪切带.非晶合金复合材料的塑性变形主要由剪切带贡献,而晶体相的存在促进了多重剪切带的形成;复合材料的载荷则主要由连续的非晶基体相承担,剪切带形成伴随自由体积的快速增加,导致非晶基体流动应力下降,复合材料承载能力降低.  相似文献   

10.
大块金属玻璃剪切带形成的“原位”压缩实验研究   总被引:1,自引:0,他引:1  
对一种锆基大块金属玻璃材料进行了室温下的准静态SEM"原位"压缩实验,并对其剪切带行为进行了研究.测得的宏观应力应变曲线表现出理想弹塑性响应.对样品变形过程中和断裂后的表面剪切带斑图进行的分析表明,多重剪切带的形成及其交割和分叉行为能显著提升其金属玻璃材料的塑性变形能力.采用Mohr-Coulomb模型对其断裂偏离最大剪应力平面的现象进行了描述.基于金属玻璃塑性变形的自由体积模型,对剪切带交割点产生的纳米尺度空洞和微裂纹形成机理进行了分析.图6,参16.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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