压实黄土力学特性室内试验研究

对山西吕梁某地黄土状填土进行室内试验研究,分析其工程力学特性,对比不同击实能下的击实曲线,表明随击实能增大,最大干密度增大而最优含水量减小.进行室内侧限压缩试验,分析含水量和击实能对压实黄土孔隙比和压缩系数的影响,试验结果表明:含水量越大压缩系数越大,随压力的增加含水量越大的压实黄土孔隙比减小越快;含水量和竖向压力相同时,随着击实能增大,土样孔隙比减小,压缩系数减小.     

压实黄土力学特性室内试验研究

对山西吕梁某地黄土状填土进行室内试验研究,分析其工程力学特性,对比不同击实能下的击实曲线,表明随击实能增大,最大干密度增大而最优含水量减小.进行室内侧限压缩试验,分析含水量和击实能对压实黄土孔隙比和压缩系数的影响,试验结果表明：含水量越大压缩系数越大,随压力的增加含水量越大的压实黄土孔隙比减小越快;含水量和竖向压力相同时,随着击实能增大,土样孔隙比减小,压缩系数减小.     

基于不同初始含水量的压实黄土力学特性试验研究

用常规击实方法制备不同击实能下的压实黄土土样,比较三个不同击实能下的击实曲线,通过室内试验研究了随含水量和击实能的变化压实黄土强度的变化规律。试验结果表明:压缩系数随含水量增加而增大,随击实能变化表现为当含水量为某一击实能对应的最优含水量时,该击实能下的压实黄土压缩系数最小;剪切强度随含水量增加降低,随击实能的变化同样与相应击实能下的最优含水量密切相关。提出严格控制含水量是提高回填土地基和路基压实质量的重中之重,并指出采用压实度作为指标控制填土压实质量时必须注意击实能的影响,以确保压实度作为压实质量控制指标的合理性。     

公路路基粉土工程特性试验研究

为研究公路路基粉土的工程力学特性,评价粉土路基的稳定性,通过室内击实试验、渗透试验、三轴试验和微观结构分析,分析粉土作为公路路基填料的工程力学性质,对比分析不同击实功作用下粉土的干密度特性,探讨压实度和孔隙比之间的变化规律以及不间级配粉土的压实性能,研究不同压实度粉土的渗透特性及其力学效应,阐述不同击实度的粉_十微观结构排列形式.研究结果表明:在公路路基填土压实过程中,对于粉土,可采用现行重型击实标准,但压实标准偏低;路基填土的渗透系数随着压实度的增大而呈非线性减小;随着压实度增加,粉土填充孔隙的效果较差.     

基于分形理论的黄土击实后粒度分布研究

基于分形理论对不同击实能和含水量条件下的粉土状黄土进行粒度分析,研究击实后土体颗粒形状的变化情况和颗粒体积的分形行为。结果表明,击实后的粉土状黄土颗粒体积分布遵循分形规律;在一定含水量条件下,分维值D会随着击实能的增加而减小;当击实能较大时,对土样颗粒造成的形状改变也更为明显;在一定击实能条件下,当土样含水量小于最优含水量时,分维值D随着含水量的增加而减小;当土样含水量大于最优含水量后,分维值D呈现离散性,没有一定的规律。     

基于分形理论的黄土击实后粒度分布的试验研究

基于分形理论对不同击实能和含水量条件下的粉土状黄土进行粒度分析,研究击实后土体颗粒形状的变化情况和颗粒体积的分形行为。结果表明,击实后的粉土状黄土颗粒体积分布遵循分形规律;在一定含水量条件下,分维值D会随着击实能的增加而减小;当击实能较大时,对土样颗粒造成的形状改变也更为明显;在一定击实能条件下,当土样含水量小于最优含水量时,分维值D随着含水量的增加而减小;当土样含水量大于最优含水量后,分维值D呈现离散性,没有一定的规律。     

压实度对黄土填方边坡变形破坏特征的影响及细微观试验研究

压实度是影响黄土填方边坡稳定性的重要因素。目前很少有学者将宏观(模型试验)、细观(三轴试验)以及微观(扫描电镜试验)等手段联合起来研究压实黄土。为此开展了不同压实度下模型试验、等压固结不排水(isobaric consolidation undrained, ICU)试验和扫描电子显微镜(scanning electron microscope, SEM)试验。分析了不同压实度下压实黄土的饱和强度、临界状态、孔隙水压力和峰值强度(u-q_max)关系,同时也分析了不同压实度下微观孔隙结构特征,统计了不同孔隙类型个数、面积以及孔隙的平均面积、孔隙率和概率熵等。研究结果表明：饱和强度、临界状态线的斜率M值、u-q_max关系均随压实度的增大而增大。随着压实度增大,试样的孔隙个数增大,但孔隙面积减小,且微小孔隙决定了压实黄土的孔隙结构;平均孔隙面积、孔隙率随压实度增大而减小,而概率熵则随压实度增大而增加。黄土填方边坡中,增大填料的压实度可以提高土体的强度,减缓水分的入渗速率。在降雨情况下,增加土体压实度能在一定程度上提高黄土填方边坡的稳定性。     

不同级配路基填土压实性能试验

针对我国公路路基填土压实特性,采用室内击实试验,绘制了不同击实功作用下和不同级配粉土、黏土的干密度曲线,探讨了不同级配的粉土、黏土的压实性能,确定了不同击实功下压实度与孔隙比、空气体积分数、饱和度之间的关系;并基于微观结构分析,探讨了压实度对填土颗粒微观结构的影响.试验结果表明:不同级配的粉土、黏土中存在一个最佳击实功...     

陕北高填方地区土体的轻型与重型击实试验对比研究

为研究陕北某高填方场地土体的击实特性,通过不同击实功对土体进行了轻型和重击实试验。探讨了重型击实试验与轻型击实试验的试验结果的关系,研究表明:轻型和重型击实试验的最大干密度均随最优含水率的增大而减小;重型击实试验的最大干密度与轻型击实试验的最大干密度在一定区间内呈二次函数关系,含水率亦然;两种击实试验的最大干密度都随锤击数的增大而增大,随最优含水率的减小而增大,相对于轻型击实试验而言,重型击实试验变化幅度更大;选取一个标段现场实测数据与模型计算值进行对比,模型计算值与现场实测值的变化趋势基本相同,证明模型计算值可靠,可用于现场压实度的理论计算。     

恒应变速率压缩中压实黄土结构特征试验研究

采用恒应变速率法测试压实黄土的力学性质,并与分级加载方法获取的数据进行比较。同时,用电阻率法测量压实黄土在压缩过程中的电阻率值,以期探究恒定含水量条件下,应变和电流频率等因素对压实黄土电阻率的影响,分析压实黄土在压缩过程中的土体结构变化规律。结果表明:恒应变速率方法能较快地确定非饱和压实黄土的压缩曲线并计算其压缩力学参数。含水量变化较小时,压实黄土竖向电阻率随应变的增大而减小,随电流频率的升高基本呈减小趋势,横向电阻率随应变的增加而逐渐减小,竖向电阻率大于横向电阻率;另外,平均结构因子和平均形状因子随着应变的增大而呈双线型减小,表明压实黄土孔隙率逐渐减小,土样稳定性增加,土颗粒间胶结作用变弱。各向异性系数随应变增大先减小随后趋于稳定,表明随着压缩竖向和横向结构单元变化速率基本一致。压缩过程中压实黄土的结构参数反映其微观结构的变化规律,可作为评价黄土力学性质的依据。     

Markedness and its Interpretation in Language Use

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.     

Features of Women's language

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

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