老顶初次断裂过程及其矿山压力显现

为研究老顶初次来压的形成与预报机理,本文建立了适于长壁采场中部范围的老顶初次断裂前后的弹性基础梁模型,并求得其解。计算结果指出老顶初次断裂发展过程有三个类型,分析了断裂前后的矿压显现,揭示了利用采场前方矿压显现的突变预报顶板来压的机理。     

论采场冒顶事故的研究

论文指出对采场冒顶事故的研究是矿山压力及其控制的重要组成部分,回顾了我国对顶板灾害研究的发展,重点分析了我国对“老顶来压预测预报”、“局部冒顶防治”和“采场顶板动态与支护质量监测”的研究,进一步论述了发展顶板灾害研究的方向。     

采场顶板压力参数的灰色预测预报

应用灰色系统理论分析采场顶板运动及支架围岩关系两个复杂系统,介绍来压步距与支护载荷两个综合灰色量的灰色预测预报方法,即模型建立、计算过程和应用实例。研究表明,灰色模型能很好地模拟或反映顶板压力参数的变化过程与内在规律。     

煤矿浅埋煤层综采面矿压事故预防

为了预测预报浅埋煤层综采工作面矿压事故灾害,采用KMJ30型采动应力监测系统对杨伙盘煤矿30108综采工作面矿压进行现场实测.通过综合分析初采期间、正常推进时期、末采期间支架实测数据,得出了工作面初次来压、周期来压平均步距,工作面倾向压力分布,工作面整体压力大小,以及特殊地段的矿压大小,掌握了工作面矿压显现规律,对杨伙盘煤矿及周边类似条件矿井矿压事故的预报与预防具有一定的指导意义.     

采场顶板破断规律及其应力状态的研究

本文用弹性理论方法分析了月亮田煤矿１３１２４采面顶板的破坏规律,并对采场顶板的应力状态进行了数值模拟,其结果与实测资料比较吻合,说明在月亮田煤矿的具体条件下,所用的分析方法是合理的,对其他采场的顶板来压的预测也具有参考价值。     

煤矿水害预测软件开发

概述了当前煤矿底板突水预测预报存在的问题，提出了用突水概率指数法预测采场底板突水的新方法，即根据影响底板突水因素对突水所作的贡献，赋予不同的权重给影响采场底板突水的各因素。使得影响底板突水的各因素定量化，建立合理的数学模型，求出突水概率指数。利用Visual Basic实现该思想，开发出底板突水预测预报的应用软件。结合肥城煤田实例，介绍该预测预报软件的具体使用过程。     

采高及复合关键层效应对采场来压步距的影响

运用有限元数值分析方法,详细研究了采高变化及关键层复合效应对关键层破断,即采场来压步距的影响,并建立了相应的采场来压步距估算公式图６,表５,参４     

大起伏山地浅埋煤层矿压现场试验研究

为探索研究大起伏山地浅埋煤层采场矿压显现,以西南山地某矿9100工作面为典型试验采场,采用理论分析、现场实测对大起伏山地赋存下的采场矿压显现特征、支架载荷分布、巷道围岩变形、超前支承压力分布进行了探索研究。研究结果表明:1采场两端来压瞬间完成,周期来压明显,初次来压突然且来压猛烈。过冲沟发育区时周期来压步距小且来压频繁,冲沟发育区过后表现为较长时空间隔的来压。2支架初撑力利用率小,来压期间支架过载率高,容易出现支架压死或压弯现象。3支承压力分布呈"下降—稳定—上升"发展趋势,超前支承压力峰值影响范围为工作面前方15 m,峰值过后超前影响范围为工作面前方30~50 m。研究成果可为类似条件下的采场提供理论借鉴,对山地顶板岩层控制探索具有现实意义。     

老顶周期断裂及顶板来压预报

本文建立了老顶周期断裂前后的弹性基础梁模型,分析了老顶断裂位置及其在采场前方的矿压显现。研究表明,老顶通常在煤壁前方断裂,断裂时煤体上出现“压缩—反弹—压缩”三个区域,利用相应的显现可成功预报顶板来压。文中讨论了有关因素对断裂位置及显现的影响。     

三交河煤矿512大采高工作面矿山压力显现规律及特征

本文针对汾河焦煤公司三交河煤矿512大采高工作面生产地质条件,通过现场实测和数值计算方法,深入分析了矿山压力显现规律及特征,结果表明,工作面基本顶初次来压步距34～38m,工作面顶板初次来压时动载系数1.4～1.8,平均1.7;工作面中部支架工作阻力大于两端支架工作阻力,不小于10000kN。研究结果对相同条件下煤层开采采场来压步距预测及支架选型具有重大的实践意义。     

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