特超稠油微观特性研究

选取胜利油田特稠油、超稠油及特超稠油油样,通过气相色谱仪、元素分析仪、分子量测定仪、原子吸收光谱仪等对稠油的微观特性进行研究。结果表明,稠油杂原子中氧的含量最高,氮的含量最低;稠油沥青质中金属元素的含量均高于胶质,且Ni与Fe的含量较高,Ca与Mg主要存在于沥青质中,胶质中很少;沥青质与胶质总的含量是影响稠油黏度的主要因素,含量越大,稠油的黏度越高,且沥青质的分子量也是影响稠油黏度的重要因素;低碳数烃的存在对稠油黏度的降低有重要的影响,作为溶剂稀释稠油,使体系的黏度降低。     

哈法亚油田原油沥青质沉积趋势预测及分析

为了研究哈法亚油田沥青质的沉积趋势,对哈法亚油田三种不同油藏原油进行四组分分离,利用胶体体系稳定性定量计算方法预测了沥青质的沉积趋势,并采用元素分析、红外光谱(FTIR)、凝胶渗透色谱(GPC)、核磁共振(1H-NMR)等分析手段对其沥青质分子结构进行了表征,探索了沥青质分子结构与沉积趋势的内在联系。研究结果表明：哈法亚油田原油沥青质有沉积的趋势,且样品A胶体不稳定指数较大,其沥青质较容易沉积。三种沥青质的结构参数存在差异,分子量、芳香度和芳香缩合度从样品A沥青质、样品B沥青质、样品C沥青质依次减少,而氢碳比(H/C比)依次增大。沥青质聚集体的稳定性与沥青质分子结构特征密切相关,H/C比值较低以及分子量、芳香度、芳香缩合度较高的样品A沥青质具有更大的稳定能,其沥青质沉淀的可能性也较大。     

伊拉克H油田原油沥青质沉积趋势预测及分析

为了研究伊拉克H油田沥青质的沉积趋势,对伊拉克H油田三种不同油藏原油进行四组分分离,利用胶体体系稳定性定量计算方法预测了沥青质的沉积趋势;并采用元素分析、红外光谱(FTIR)、凝胶渗透色谱(GPC)、核磁共振(1H-NMR)等分析手段对其沥青质分子结构进行了表征,探索了沥青质分子结构与沉积趋势的内在联系。研究结果表明:伊拉克H油田原油沥青质有沉积的趋势,且样品A胶体不稳定指数较大,其沥青质较容易沉积。三种沥青质的结构参数存在差异,相对分子质量、芳香度和芳香缩合度从样品A沥青质、样品B沥青质、样品C沥青质依次减少,而氢碳比(H/C比)依次增大。沥青质聚集体的稳定性与沥青质分子结构特征密切相关,H/C比值较低以及相对分子质量、芳香度、芳香缩合度较高的样品A沥青质具有更大的稳定能,其沥青质沉淀的可能性也较大。     

伊朗北阿扎德干油田沥青质沉积特征

伊朗北阿扎德干油田原油的四组分和气相色质联用分析表明,原油饱和烃碳链分布范围较广,直连烷烃主峰碳为C16,原油重质组分含量相对较高,石蜡组分少,芳烃组成非常复杂,其沉积环境为强还原和高盐度海相沉积环境;胶体不稳定系数及原油的流变性分析说明,该原油容易发生沥青质沉积;对伊朗原油沥青质初始絮凝点和沉淀量的研究发现,剂油比为0.21 mL/g时,伊朗原油沥青质开始发生絮凝,利用标度方程对沥青质沉积的预测表明,当剂油比为0.27 mL/g时,伊朗原油开始出现沥青质沉积,分子量较大的沉淀剂需要较大浓度才能引发沥青质沉淀,沥青质的沉淀量随沉淀剂分子量的增大而减小;分析注入不同体积天然气的特征化原油拟组分的变化情况,发现气举采油会导致沥青质的沉积初始压力升高,沥青质容易在井筒内沉积。     

原油超声降黏机制

采用旋转黏度计、显微镜、石油离心机和紫外分光光度计测量超声处理不同时间委内瑞拉原油的黏度、沥青质粒径、原油-正庚烷稳定性和沥青质质量分数的变化。结果表明:原油超声处理0～20 min内,空化作用致使大量沥青质颗粒破裂,沥青质粒径变小,分布变均匀,原油黏度降低;处理超过20 min后,破裂的沥青质颗粒重新聚集,粒径变大,原油黏度增加;超声处理使原油中沥青质质量分数降低。     

基于最小二乘支持向量机的二氧化碳驱油沥青质沉积对储层伤害的动态分析

油田开发过程中注CO2驱替原油常会发生沥青质沉积现象,沥青质沉积由于吸附和桥塞作用会伤害储层,会降低储层的孔渗性。本文利用数值模拟方法研究沥青质沉积过程,及对油田实际生产的影响。首先通过LSSVM机器学习算法拟合了沥青质沉积与气体浓度及压力之间的非线性关系;之后运用渗透率伤害GPT模型来建立砂岩储层沥青质沉积量与渗透率降低率的伤害模板;最后建立了五点井网下的地质模型,模拟相应工作制度下沥青质伤害前后的注入井注入能力、生产井生产能力及剩余油分布状况。模拟结果表明,沥青质沉积主要集中在近井地带,对注入井的注入能力影响较大,同时由于沥青质对储层的伤害会导致渗流阻力的增大影响气水波及效率,从而引起生产井产量的下降及最终采收率的降低。     

伊朗BA原油沥青沉积及抑制高压模拟实验

在原油的开釆过程中,沥青质沉积问题可能发生于各个环节,其中在井筒或地面管线的沉积可能造成堵塞,降低生产运行效率,沉积严重时会导致油井停产。为了更好地预防沥青质沉积,对伊朗BA原油样进行族组成分析,其胶体不稳定指数CII大于0.9,易发生沥青质沉积。采用压差法对BA原油沥青质析出压力进行高压模拟实验评价,而压差法主要是通过压降的变化来判断沥青质的沉积。结果表明:在50~96℃下,当井筒压力降低到一定程度时,原油中沥青质会析出,使压降显著增加;且沥青质析出压力随着温度升高减小,随着气油比增大而增大。采用正己烷沉淀法对8种抑制剂进行初选,阳离子表面活性剂YAI-4、YAI-6的抑制效果较好,其抑制率可达88.9%和95.6%;同时通过高压模拟实验评价,同样条件下YAI-6比YAI-4能更好地稳定原油中的沥青质,在等温降压过程中,用YAI-6处理的原油在不同条件下均没有检测到明显的压降变化,表明YAI-6对于伊朗BA原油是一种非常有效的沥青沉积抑制剂。     

CO2驱油中沥青质沉积条件及对驱油效果影响的研究

在模拟榆树林油田地层条件下,通过高压物性及CO2驱油实验,研究了注CO2后沥青质的沉积条件,并对沥青质沉积对CO2驱油效果的影响进行了分析。结果表明:在地层温度(108℃)下,注气压力达到28.4 MPa时可明显出现沥青质沉积。随着温度增加,形成沥青质沉积的压力增加,沥青质沉积的程度增加;随CO2注入压力的增加,沥青质沉积量增加,原油中的沥青质含量降低,胶质、芳烃、饱和烃含量增加;达到28 MPa后沥青质沉积量逐渐减少,采出油中沥青质含量增加。沥青质沉积使采收率降低12.29%以上,在(25—28)MPa时采收率降低幅度最大。     

伊朗BA原油沥青沉积及抑制高压模拟实验研究*

在原油的开釆过程中,沥青质沉积问题可能发生于各个环节,其中在井筒或地面管线的沉积可能造成堵塞,降低生产运行效率,沉积严重时会导致油井停产。本文对伊朗BA原油样进行族组成分析,其胶体不稳定指数CII大于0.9,易发生沥青质沉积。采用压差法对BA原油沥青质析出压力进行高压模拟实验评价,结果表明：在50~96℃下,当井筒压力降低到一定程度时,原油中沥青质会析出,使压降显著增加;且沥青质析出压力随着温度升高减小,随着气油比增大而增大。采用正己烷沉淀法对8种抑制剂进行初选,阳离子表面活性剂YAI-4、YAI-6的抑制效果较好,其抑制率可达88.9%和95.6%;同时通过高压模拟实验评价,同样条件下YAI-6比YAI-4能更好的稳定原油中的沥青质,在等温降压过程中,用YAI-6处理的原油在不同条件下均没有检测到明显的压降变化,表明YAI-6 对于伊朗BA原油是一种非常有效的沥青沉积抑制剂。     

稠油分散体系中黏度与化学组成的灰熵关系分析

采用灰色关联熵分析法研究了稠油黏度及其族组成、有机杂原子、金属元素和主要官能团的关联,探讨了物系黏度随稠油分散系统微观结构的变化规律.结果表明:①沥青质是影响稠油黏度的最主要的因素,稠油体系中沥青质聚集分相的形成特性取决于稠油体系的物理结构,即稠油胶体构造的稳定性.胶体稳定性越高,沥青质越不容易从稠油分散体系中聚集沉淀.②在沥青质分子单元叠积过程中,由沥青质的杂原子因素、过渡金属因素、芳香环结构因素和脂肪性侧链因素共同决定的化学作用的影响是第一位的,其中芳香环结构因素和杂原子因素的影响最为显著,而由稠油体系不稳定性构成的物理作用的影响则居于次要地位.     

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