海洋天然气水合物测井评价研究进展

资源量巨大的天然气水合物越来越引起人们的重视。针对目前海洋天然气水合物储层的测井评价问题,介绍了海洋天然气水合物的晶格结构、物理性质、分布形式和形成条件,结合天然气水合物的物理性质和储层特征,分析了海洋天然气水合物的常规测井响应特征。根据大量文献调研,得出目前利用测井方法求取天然气水合物储层的孔隙度和饱和度等参数的主要方法,对南海神狐海域含天然气水合物储层的实例站位进行泥质含量、天然气水合物饱和度评价。提出实验室合成人工岩芯研究天然气水合物时,需考虑泥质的存在。通过总结海洋天然气水合物测井评价研究进展的调研成果,为今后大规模海洋天然气水合物的储量预测及勘探开发提供重要依据,对天然气水合物资源的有效开采具有重要现实意义。     

南海北部天然气水合物的形成分解与微生物的偶联关系

微生物在天然气水合物的形成和分解中扮演了重要的角色.南海北部是我国天然气水合物未来开发的战略选区之一,目前已多次在该海域采集到天然气水合物样品,证实了南海北部蕴藏着丰富的天然气水合物资源.通过分析天然气水合物形成与分解同微生物的偶联关系,综述了与天然气水合物形成分解有关的微生物类型及其标志化合物,结合我国南海北部天然气水合物赋存或潜在赋存区的微生物相关研究工作进展,提出未来使用微生物地球化学方法勘探天然气水合物的技术指标和相关的研究方向.     

海底天然气水合物绞吸式开采方法研究

 根据海底天然气水合物藏特点,结合绞吸式挖泥船工作原理和大洋多金属结核开采技术,提出了一种全新的绞吸式海底天然气水合物开采方法,克服了海底天然气水合物开采依赖构筑封闭开采环境的技术瓶颈;然后根据管道输送原理和两相流理论,对绞吸式开采方法的提升系统进行了水力参数分析。由分析结果可知,将体积浓度为15%~25%天然气水合物流体从1 000 m海底提升到海面所需泵的扬程为30~50 m;将体积浓度为10%~20%天然气水合物流体从4 000 m海底提升到海面所需扬程为90~150 m,现有的矿浆泵就能满足要求;由于天然气水合物和海底沉积物硬度较低,并且其混合流体的密度与海水密度相差不大,采用矿浆泵进行直接输送其对泵的磨损不会严重,能保证系统长期稳定的工作,证明了该开采方法在理论上是可行的。     

南海固态流化开采天然气水合物设计参数优化

确保水合物开采工程安全,是实现南海固态流化开采天然气水合物商业化开采的关键和前提。为研究钻井参数对固态流化开采天然气水合物过程中多相流特性和工程安全的影响,建立了考虑水合物热分解的井筒多相流模型并分析了钻井参数对工程安全的影响,在此基础上,提出了确保固态流化开采天然气水合物工程安全的具体工程参数选择办法。研究结果表明:为确保固态流化开采天然气水合物工程安全,排量应该控制在40-50 L/s之间;如果地温梯度高于0.04℃/m,钻井时应该提前冷却钻井液;钻井液密度应该控制在1.20-1.25 g/cm3之间;为最大化水合物开采效率,钻速应该保持在20m/h左右。研究成果可为中国南海固态流化商业化开采天然气水合物提供理论指导和技术支持。     

从能源短缺的角度看广东海洋新能源开发前景

广东省是海洋大省,蕴藏着潜力巨大的海洋新能源——天然气水合物。其良好的开发前景,对解决广东能源短缺,实现经济、社会可持续发展,具有重要战略意义和现实意义。广东省十分有必要积极参与到这种新型能源的研究和开发工作中,为调查研究和评价南海北部天然气水合物资源,早日实现商业性开采做出重要贡献。     

海洋天然气水合物藏开采若干问题研究

文章阐述了在开采天然气水合物方面所取得的研究进展,包括天然气水合物开采模型及数值模拟,天然气水合物开采物理模拟相似准则,天然气水合物开采方法研究等。建立、完善了天然气水合物开采的数学模型,并以此为基础建立了降压开采水合物物理模拟相似准则。降压法开采单一水合物藏,在某些情况下开采能量不足会导致藏内结冰严重。对下伏气的天然气水合物藏而言,水合物能够提高产气量、延长稳产时间。结合降压和注热的优势提出了注温水-降压法联合开采方法,该方法具有稳产时间较长、稳产气速度高的特点。     

2017年天然气水合物研发热点回眸

 2017年，天然气水合物研发领域散发出强劲活力，发生了一系列重大事件。本文回顾了2017年日本南海海槽天然气水合物试采、中国神狐海域天然气水合物试采、中国荔湾海域天然气水合物试采、天然气水合物作为新矿种等重大事件和进展，盘点了天然气水合物油气系统在中国南海神狐海域等主要地区的应用与研究、动力学抑制剂、开采方法、沉积物稳定性、环境效应等研究热点，部分展示了中国在天然气水合物领域作出的贡献，并进一步分析了天然气水合物未来研究热点。     

海洋和陆域天然气水合物开发的环境影响比较

我国在南海和青海冻土区发现了天然气水合物矿藏,但正视并研究天然气水合物开发的潜在环境影响风险是安全合理开发利用它的前提.由于海洋和陆域天然气水合物有其自身的赋存条件,它们的环境影响风险必然存在差异：海洋天然气水合物具有气候效应、海洋生态威胁、海底地质灾害等潜在环境影响风险,而陆域天然气水合物的潜在环境影响风险表现在气候效应、冻土层和高寒草甸破坏、陆地生态威胁、地陷和塌方等方面.可以通过采用安全可靠的具有针对性的开发技术并控制工程过程等措施来应对环境影响风险.     

天然气水合物勘探开发专辑

天然气水合物是一种潜在清洁油气接替能源,我国海域水合物资源量巨大,约为800亿吨油当量,实现天然气水合物安全高效开采对我国建设海洋强国、保障能源安全和实现"双碳"目标意义重大.广大科技工作者针对天然气水合物勘探开发过程中的理论和技术难题进行了大量研究并取得了丰硕成果.     

海域天然气水合物自入式开采装置及其可行性研究

为解决目前海域天然气水合物试采案例所采用钻井开采技术中存在的深水作业成本高、井筒结构易损坏及长期稳定开采难度大等问题,提出一种新型海域天然气水合物自入式开采装置及方法.该方法无需使用大型的钻井设备,由自入式开采装置携带相关设备依靠重力冲击进入储层,然后进行降压开采,待作业结束后可通过拉拔进行回收,重复使用.建立冲击贯入...     

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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