直流架线式电机车运输系统杂散电流的危害与防治

简介了公乌素煤矿三号井的生产概况,对 1000运输大巷利用直流架线式电机车运输中产生的杂散电流造成的危害进行了分析,就如何减少杂散电流的危害提出了可行性的措施。     

露天矿直流供电系统杂散电流分析

通过建立露天煤矿电气化铁道简化的均匀分布参数模型，分析了直流杂散电流的分布规律和影响直流杂散电流的主要因素，并提出了抑制杂散电流应采取的有效措施。直流杂散电流的主要影响因素可分为电压因素和电阻因素两个方面。利用本方法分析露天矿杂散电流的分布规律，进而采取有效的抑制措施，减小杂散电流的危害，对保证安全生产具有积极作用。     

地铁中杂散电流的防治设计

地铁产生的杂散电流带来了很大危害,因此必须加强对地铁杂散电流的防治。基于此,本文分析了杂散电流防治的基本原则,对杂散电流仿真进行了深入研究,探讨了杂散电流设计方案。     

新型地铁杂散电流腐蚀智能监测系统研究

本文通过对地铁杂散电流的危害及监测原理的分析,结合杭州地铁杂散电流监测的要求,构建了一套基于Web的杂散电流腐蚀智能监测系统,开发了数据查询与分析系统,实现了对地铁杂散电流的监测与预报。     

城市轨道杂散电流的危害与防治

城市轨道地下区段中,因回流轨与大地不能绝对绝缘,导致有部分电流渗入地下形成杂散电流。本文介绍了杂散电流的成因,并论述了杂散电流的危害以及目前常用的防治措施。     

浅谈杂散电流的产生、危害和防治

该文通过对井下架线式电机车直流牵引网络系统中杂散电流产生原因的分析,较全面地介绍了杂散电流在井下的危害,有针对性地提出了防止杂散电流产生和扩散的有效措施,对掌握和治理杂散电流有较大的帮助。     

论杂散电流的防护

防止杂散电流的腐蚀在国外已做了大量的研究。但国内对这方面的研究还很不够,本文首先简要介绍了杂散电流常用的防护技术。杂散电流对供电系统周边的环境和基础设施的危害很大。对杂散电流的防护应采用＂以防为主,以排为辅,防排结合,加强监测＂的原则。     

煤矿井下杂散电流的危害与防治

对煤矿井下杂散电流产生的原因和对煤矿安全生产的危害进行了分析．对杂散电流的定期测试和防治措施进行了研究和探讨。     

煤矿井下杂散电流成因、危害及防治浅析

本文首先对煤矿井下杂散电流产生的原因进行了分析,然后指出杂散电流对煤矿生产系统的危害,并提出了相应的治理方案。     

浅析地铁杂散电流的防护

阐述了地铁杂散电流产生的原理和造成的的危害,介绍现今地铁杂散电流防护的现状,提出极性保护在地铁的杂散电流保护中的重要意义。详细分析各种常见的防护方法情况,对工程设计及学术学习有一定的参考价值。     

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