硅灰耐高温低密度水泥浆的研究

用硅灰作高温稳定剂,漂珠为减轻剂,与G级油井水泥配制密度为1•5g/cm3的水泥浆。该水泥浆的特点是:①密度低,用水量小;②在低温下强度高、滤失量低、析水为零、稠化时间可调、流变性好,能满足施工工艺的要求;③水泥石能承受高温,在350℃、20MPa下养护3天,强度达12MPa。该低密度水泥浆可用于低压易漏地层稠油热采井的固井,并可大大减轻因高温引起的水泥石强度衰退,延长油井的寿命。     

耐高温低密度油井水泥的研究及应用

根据国内油田低压浅层稠油热采井固井需求，研制开发了一种新型耐高温低密度油井水泥。该水泥由基础熟料和天然非晶态硅质材料组成，在不同地层温度(18—75℃)范围内，其密度可在1．37—1．53g／cm^3之间调节，48h抗压强度大于10MPa，高温(300℃)水热条件下7d的抗压强度不衰退，其综合工程性能满足浅层稠油井固井技术要求。190口井的现场应用结果表明：该水泥具有施工工艺简单，造浆率高，抗高温性能优异等特性，可显著提高低压浅层稠油热采井的固井质量和原油产量。     

硅铝质掺合料对含石灰石组分水泥基材料硫酸盐侵蚀的影响

通过腐蚀试验后试件的外观形貌和强度变化、腐蚀物相分析,研究较低环境温度下硅铝质掺合料对含石灰石组分水泥基材料硫酸盐侵蚀的影响。结果表明：随着硅铝质掺合料掺量的增加,含石灰石粉硅酸盐水泥试件外观完整性明显提高,强度损失率逐渐降低;当硅铝质组分掺量为15%、30%时,矿粉对含石灰石组分水泥基材料抗硫酸盐侵蚀的改善作用明显优于相同掺量的粉煤灰;硅铝质组分能够延缓较低环境温度下含石灰石粉硅酸盐水泥的硫酸盐侵蚀,抑制腐蚀物相碳硫硅钙石的生成。     

纳米SiO2对硅酸盐水泥性能影响实验研究

初步研究了粒径在纳米级的硅粉(纳米SiO2)的基本性质及纳米SiO2对浆体流动性、水泥凝结时闻、抗压与抗折强度的影响，并利用XRD、SEM等微观手段，分析了其对水泥性能影响的机理．结果表明，纳米SiO2具有良好的水泥适应性，能较好改善硅酸盐水泥的性能，其最佳掺量为胶凝材料总质量的5％～6％。     

热养护对高性能混凝土强度的影响

研究了热养护制度对由普通硅酸盐水泥、硅灰、粉煤灰或(和)石英粉等磨细掺合料配制的高性能混凝土抗压强度、抗折强度的影响。试验表明,高温养护更有利于混凝土的抗压强度发展,热水养护更有利于混凝土的抗折强度发展。     

DL水泥减阻剂的研制与应用

DL减阻剂是一种新型水泥外加剂,具有降低水灰比,大幅度改善浆液流动性和增强等优点。既能满足地质钻钻探水泥护壁堵漏用硫铝酸盐地勘水泥的需要,又能用于油井固井注水泥满足泵送减阻的要求,并与CaCl_2复合对普通硅酸盐水泥全面改性有广泛的应用效果。     

早强速凝水泥在套保油田的应用

API系列油井水泥（J级水泥已经取消）的应用温度一般是在38℃～110℃之间，通过使用水泥外掺料或外加剂来调节水泥浆的性能，使之适用于低温或高温环境。但吉林石油集团公司套保油田浅层稠油井18℃的井底静止温度，使得API系列水泥无法满足冬季固井施工的基本技术要求。由于国内尚无用于低温地层条件（〈30℃）的油井水泥及其外加剂体系，     

水泥硅灰粉砂土抗剪强度实验研究

以宁夏银川市某道路路基填筑的粉砂性土为实验对象,分别对水泥粉砂土和水泥硅灰粉砂土进行了三轴实验研究,分析了硅灰对水泥粉砂性土力学参数的影响规律.结果表明,硅灰替代水泥虽然不能改善水泥粉砂土的摩擦角,但可以改善水泥粉砂土的黏聚力,且随着硅灰替代量的增加,黏聚力呈先增加后减小的趋势.3%水泥粉砂土的硅灰最佳替代量为12.05%;5%水泥粉砂土的硅灰最佳替代量为16.5%.随着水泥掺量的增加,最佳硅灰替代量将增加;不同水泥掺量的粉砂土,硅灰对其抗变形能力影响不同,主要取决于水泥土的刚柔性.     

热采井化学防砂剂试验研究

针对孤岛油田稠油油藏属疏松砂岩油藏易出砂这一现状研制开发了一种新型的热采井防砂剂,即ＲＣ—Ｇ防砂剂．这种防砂剂是在特制的ＴＬ颗粒表面涂敷一层带有潜伏性固化剂的高温粘合剂,注汽前挤入地层,在油层温度下,固化剂将粘合剂交联成不溶不熔体型产物,在油井近井地带形成一个较高强度的挡砂屏障,防止油井生产时出砂．这种防砂剂适用温度６０ ～３５０℃,３５０℃条件下抗折强度大于４．０ＭＰａ,渗透率可达３４．６μｍ ２,防砂不影响井的供液能力．采用这种防砂剂在热采井上试验１８ 井次,成功率８７．５％ ,和以往应用的高温涂敷砂相比,成功率明显提高,有一定的推广应用价值．     

稠油热采井固井技术的研究进展

综述了热采井固井水泥浆体系和预应力固井工具的国内外研究最新进展。重点介绍了普通波特兰高温水泥、高铝水泥和特种磷酸盐水泥等耐高温水泥,以及高强低密度水泥、泡沫水泥等高性能低密度水泥浆;并介绍地锚、热应力补偿器这两个主要预应力固井工具的应用现状。     

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     

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     

Journal of Donghua University ( English Edition) Contents of Volume 31

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