新型补口材料在埋地管道补口修复中的应用

埋地管道补口失效主要是由于补口防腐层质量问题、补口施工质量问题和补口防腐层在使用环境中的老化失效所导致。介绍了几种新型补口材料在西部某管道补口修复和施工中的成功应用,对补口修复后防腐层的安装质量进行了检测与评价,跟踪了管道运行1年、3年、4年后补口防腐层的性能,并分析了结果。     

西气东输二线管道腐蚀特点与防护措施

西气东输二线管道沿线不同土壤中管道的腐蚀特点为Cl-离子起主导作用,管道的腐蚀主要为外腐蚀。管道防腐使用强制电流保护方法以及临时阴极保护措施的方法,并使用排流方法消除交、直流干扰。管道以及冷弯管采用3层PE,热煨弯管采用双层熔结环氧粉末,管道补口采用聚乙烯热收缩带。     

燃气管线定向钻穿越防腐层的选择

定向钻穿越方式因其投资少、工期短、安全环保等优点,成为道路、河流穿越的首选方式,但在回拖过程中,有可能损伤管道防腐层。因此,在燃气管道定向钻穿越施工工艺中,外防腐层的选用至关重要。本文结合深圳市实际施工条件,通过对国内相关单位所作的定向钻穿越事例调查和研究,并对几种新型管道防腐层保护措施进行了探讨,确定深圳市高压燃气管线定向钻穿越外防腐采用3PE＋穿越专用热收缩套和帕罗特两种方式。     

油田小口径钢管预补口过渡区耐蚀性能研究

小口径钢管预补口过渡区是内防腐搭接部位结构中的薄弱环节,一旦防腐层出现老化脱落,搭接部位裸露的异种金属间将发生不同程度电偶腐蚀而缩短管道使用寿命。为解决这一关键技术难题,开展了小口径钢管预补口过渡区耐蚀性研究,利用微区电化学技术分析了浸于5%NaCl溶液中的预补口结构搭接部位微区电化学性能、临界区域腐蚀形貌等,取得了减缓电偶腐蚀的有效方法。     

西气东输工程管道线路环境地质与地质灾害及其评价

我国西部天然气资源比较丰富,东部市场前景广阔."西气东输"就是将我国西部地区的天然气通过管道输往东部地区,以满足东部地区对天然气能源的迫切需要.西气东输工程管道线路横贯我国东部和西部,长达4 000km,大部分线路地质环境复杂,地质灾害类型多样,作好该项目的前期研究论证和管道线路岩土工程勘察,制定并实施地质环境保护规划和地质灾害防治对策,对确保西气东输工程的顺利实施和管道安全施工与运营十分重要.     

SHAFER气液联动执行器在西气东输的应用

美国EMERSON公司的SHAFER执行器主要以气体或者液压油为驱动动力源，在西气东输管道上起着控制阀门开关的功能，通过对设备的结构、工作原理的充分阐述，以及对SHFER阀的充分分析，论述SHFER执行器在西气东输的具体应用。     

浅谈西三线乌苏压气站—玛纳斯压气站管道工程试压施工技术

西气东输三线西段(二标段)如苏压气站-玛纳新压气站长输管道工程,由于管线距离较长及且易引起管道长距离造成落差而影响试压.管道在该段试压存在一定难度,西三线西段在该段采用分段试压的施工技术进行施工,取得较好效果.     

焊接技术在长输管道施工中的应用

西气东输项目的日益发展在我国的石油战略和国家能源发展扮演着越来越重要的地位,长输油、气管道加速朝着大口径、高压力输送的方向发展。与其配套的焊接技术的掌控已成为西气东输油气管道工程施工成败的关键,它直接关系到工程质量、     

浅谈PCM法在沈阳桃仙机场输油管线检测中的应用

PCM是Pipeline Current Mapper的简称,即为管中电流法或多频管中电流法,它通过计算管道防腐层绝缘电阻来判断管道外防腐层的状态,在管道检测中得到较为广泛的应用。本文详细介绍了PCM法（即多频管中电流法）定位管线的原理,以及如何通过A字架确定防腐层漏电点,并结合沈阳桃仙机场输油管线检验案例,详细分析了如何利用这些方法进行长输管道在线检测,以及分析了进行这些项目检测的可行性和存在的不足。实践证明,利用PCM法进行输油管道检测是行之有效的。     

浅谈西三线二标段全自动焊接技术的应用

西气东输三线西段(二标段)由于主线路管道长、管径大、管壁厚(φ1219×18.4/22)且工期紧,管道在施工进度的提速上存在很大的难度.西三线西段(二标段)沿用西二线使用的全自动焊接技术进行施工,在加快施工进度上取得较好的效果.在今后的大规模长输管道施工中,将得到更广泛的应用.     

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.     

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.     

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<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