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Journal of Natural Gas Chemistry 2009年第2期18卷 205-210页

作者： peng zhang qingbai wu yingmei wang State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Lanzhou 730000 Gansu China

Hydrate formation and dissociation processes are always accompanied by water migration in porous media, which is similar to the ice. In our study, a novel pF-meter sensor which could detect the changes of water content inside sand was first applied to hydrate formation and dissociation processes. It also can study the water change characteristics in the core scale of a partially saturated silica sand sample and compare the differences of water changes between the processes of formation and dissociation of methane hydrate and freezing and thawing of ice. The experimental results showed that the water changes in the processes of formation and dissociation of methane hydrate were basically similar to that of the freezing and thawing of ice in sand. When methane hydrate or ice was formed, water changes showed the decrease in water content on the whole and the pF values rose following the formation processes. However, there were very obvious differences between the ice thawing and hydrate dissociation.

关键词： methane hydrate ice formation and dissociation process freezing and thawing process water change

Water transfer characteristics in the vertical direction during methane hydrate formation and dissociation processes inside non-saturated media

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Journal of Natural Gas Chemistry 2010年第2期19卷 139-145页

作者： peng zhang qingbai wu Guanli Jiang Jing Zhan yingmei wang State Key Laboratory Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 Gansu China

In order to study water transfer characteristics inside non-saturated media during methane hydrate formation and dissociation processes,water changes on the top,middle and bottom locations of experimental media during the reaction processes were continuously followed with a novel apparatus with three pF-meter *** sand,fine sand and loess were chosen as experimental *** was experimentally observed that methane hydrate was easier formed inside coarse sand and fine sand than inside *** hydrate formation configuration and water transfer characteristics during methane hydrate formation processes were very different among the different non-saturated media,which were important for understanding methane hydrate formation and dissociation mechanism inside sediments in nature.

关键词： water transfer methane hydrate formation and dissociation processes non-saturated

Effects of Temperature Gradient and Cooling Rate on the Formation of Methane Hydrates in Coarse Sand

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China Petroleum Processing & Petrochemical Technology 2013年第2期15卷 42-52页

作者： wang yingmei wu qingbai zhang peng Jiang Guanli State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Western China Energy & Environment Research Center Lanzhou University of Technology

Temperature gradient and cooling rate have an obvious effect on formation of methane hydrate. The process for formation of methane hydrate in coarse sand is monitored to tmderstand the relationship between temperature gradient and cooling rate and nucleation, growth and distribution of methane hydrate by using the electrical resistivity method. The results show that the change of resistivity can better reflect the nucleation and growth and distribution of methane hydrate. Temperature gradient promotes the nucleation, formation, and formation rate of methane hydrate. At a temperature gradient of 0.11℃/cm, the rate of methane hydrate formation and saturation reaches a maximum. Cooling rate has little effect on the methane hydrate formation process. Judging from the outcome of final spatial distribution of methane hydrate, the cooling rate has an obvious but irregular effect in coarse sand. The effect of tempera^re gradient on distribution of methane hydrate in coarse sand is less than that of cooling rate. At a temperature gradient of 0.07℃/cm, methane hydrate is distributed uniformly in the sample. If the temperature gradient is higher or lower than this value, the hydrate is enriched in the upper layer of sample.

关键词： methane hydrate cooling rate temperature gradient resistivity formation hydrate distribution

Relation between soil matrix potential changes and water conversion ratios during methane hydrate formation processes in loess

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Journal of Natural Gas Chemistry 2011年第2期20卷 140-144页

作者： peng zhang qingbai wu Guanli Jiang Yibin Pu State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 Gansu China

With a new apparatus designed and assembled by ourselves, the matrix potential of non-saturated loess was firstly measured and studied during methane hydrate formation processes. The experimental results showed that during two formation processes, the matrix potential changes of the loess all presented a good linear relationship with water conversion ratios. In addition, although it was well known that the secondary gas hydrate formation was easier than the initial, our experimental results showed that the initial hydrate formation efficiency in non-saturated loess was higher than that of the secondary.

关键词： hydrate formation non-saturated loess matrix potential water conversion ratio

Methane hydrate formation comparisons in media with and without a water source supply

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Research in Cold and Arid Regions 2014年第4期6卷 293-301页

作者： peng zhang qingbai wu State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

Water is a necessary element during gas hydrate formations. Therefore, by analyzing water depletion changes in media, the reaction characteristics of methane hydrate in media can be studied. In this study, two water sources supplying some liquid water which may be consumed by the methane hydrate formation reactions were designed and assembled. Using them, the full formation processes of methane hydrate was studied. Experimental results show the following： If heat released from nucleation reaction of methane hydrate is diffused rapidly, the nucleation ratios will be enhanced discernibly. While the hydrate is formed, a force is generated that sucks fresh water from the source into the vicinity of the hydrate, slowing down the cementation process and causing some hydrate grain dissociation. As a result of cementation differences, the hydrate reaction processes with different water sources present linear or quadratic equation characteristics. After a few repeated dissociation and formation processes of some hydrate grains caused by the fresh water, the gas amounts contained in hydrate will be significantly enhanced.

关键词： water source water transfer methane hydrate formation process

Water transfer characteristics during methane hydrate formation and dissociation processes inside saturated sand

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Journal of Natural Gas Chemistry 2010年第1期19卷 71-76页

作者： peng zhang, qingbai wu, Yibin Pu, Guanli Jiang, Jing Zhan, yingmei wang State Key Laboratory, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, Gansu, China [a] State Key Laboratory Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 Gansu China

Gas hydrates formation and dissociation processes inside porous media are always accompanied by water transfer behavior, which is similar to the water behavior of ice freezing and thawing processes. These processes have been studied by many researchers, but all the studies are so far on the water transfer characteristics outside porous media and the water transfer characteristics inside porous media have been little known. In this study, in order to study the water transfer characteristics inside porous media during methane hydrate formation and dissociation processes, a novel apparatus with three pF-meter sensors which can detect water content changes inside porous media was applied. It was experimentally observed that methane hydrate formation processes were accompanied by water transfer from bottom to top inside porous media, however, the water behavior during hydrate dissociation processes was abnormal, for which more studies are needed to find out the real reason in our future work.

关键词： methane hydrate formation and dissociation processes: water transfer inside porous media saturated

Calculation method for thickness of discontinuous boundary layer of engineering pavement

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Research in Cold and Arid Regions 2016年第6期8卷 461-466页

作者： ZhongQiong zhang qingbai wu peng zhang SiRu Gao State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-environment and Resources Chinese Academy of Sciences Beiluhe Observation Station of Frozen Soil Environment and Engineering Northwest Institute of Eco-environment and Resources Chinese Academy of Sciences

The boundary layer is a buffer layer of water and heat exchange between the atmosphere and permafrost. Based on the atmospheric boundary layer and heat transfer theory, we established a method for determining the boundary layer thickness of engineering pavement （asphalt and sand pavement） in permafrost region. The boundary layer can be divided into the Boundary Layer Above Surface （BLAS） and the Boundary Layer Below Surface （BLBS）. From in-situ monitoring data, the thickness of BLAS was determined through the laminar thickness, and the thickness of BLBS was determined through ground temperature, the heat conduction function, and the mean attenuation function （α）. For asphalt pavement, the BLAS thickness varied between 2.90 and 4.31 mm and that of BLBS varied between 28.00 and 45.38 cm. For sand pavement, the BLAS thickness varied between 2.55 and 3.29 mm and that of BLBS varied between 15.00 and 46.44 cm. The thickness varied with freezing and thawing processes. The boundary layer calculation method described in this paper can provide a relatively stable boundary for temperature field analysis.

关键词： boundary layer scope average attenuation coefficient pavement permafrost

δ18O,δD and d-excess signatures of ground ice in permafrost in the Beiluhe Basin on the Qinghai-Tibet Plateau,China

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Research in Cold and Arid Regions 2017年第1期9卷 38-45页

作者： YuZhong Yang qingbai wu HuiJun Jin peng zhang State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China

In this paper, stable isotope （δ18O, δD） investigations were completed in ground ice from a deep borehole in the Beiluhe Basin on northern Qinghai-Tibet Plateau to unravel the isotopic variations of ground ice and their possible source water. The δ18O and δD of ground ice show distinctive characteristics compared with precipitation and surface water. The near-surface ground ice is highly enriched in heavier isotopes （δ18O and δD）, which were gradually depleted from top to bottom along the profile. It is suggestive of different origin and ice formation process. According to isotopic variations, the ice profile was divided into three sections： the near-surface ground ice at 2.5 m is frozen by the active-layer water which suffered evaporation. It is possible that ground ice between 3 and 4.2 m is recharged by the infiltration of snowmelt. From 5 to 6 m, the ground ice show complex origin and formation processes. Isotopic variations from 6 to 11.1 m and 20.55 m indicate different replenishment water. The calculated slope of freezing line （S=6.4） is larger than the experimental value （5.76）, and is suggestive of complex origin and formation process of ground ice.

关键词： Qinghai-Tibet Plateau ground ice stable isotope source water ice formation process

多孔介质水合物中未水合水的核磁共振实验研究

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中南大学学报（自然科学版） 2022年第4期53卷 1525-1535页

作者：展静张鹏王英梅吴青柏中国科学院西北生态环境资源研究院冻土工程国家重点实验室甘肃兰州730000 中国科学院大学北京100049 兰州理工大学能源与动力工程学院甘肃兰州730050

利用低场核磁共振技术开展多孔介质水合物中未水合水研究,提出一种定量分析含水合物的多孔介质未水合水含量的实验方法。研究结果表明:颗粒粒径越小,未水合水含量较高;当颗粒粒径相同时,初始含水量越高未水合水含量也越高;初始压力越低... 详细信息

利用低场核磁共振技术开展多孔介质水合物中未水合水研究,提出一种定量分析含水合物的多孔介质未水合水含量的实验方法。研究结果表明:颗粒粒径越小,未水合水含量较高;当颗粒粒径相同时,初始含水量越高未水合水含量也越高;初始压力越低,未水合水含量越高;未水合水含量较高时多分布于较大孔隙和大孔隙中,未水合水含量较低时多分布于小孔隙和较大孔隙中。在水合物形成过程中,颗粒粒径、初始含水量及初始压力均对水分的迁移有一定影响,最终影响未水合水的含量及孔隙分布变化。

关键词：多孔介质未水合水低场核磁共振核磁信号强度 T2弛豫时间

Distinct regulatory mechanism of immunoglobulin gene transcription in epithelial cancer cells

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Cellular & Molecular Immunology 2010年第4期7卷 279-287页

作者： Xiaohui Zhu Lina wu Li zhang peng Hao Shuai zhang Jing Huang Jie Zheng Yinan Liu Wenjun Li yingmei zhang Chunyan Zhou Youhui zhang C Cameron Yin Xiaoyan Qiu Peking University Center for Human Disease Genomics BeijingChina Department of Biochemistry School of Basic Medical SciencePeking UniversityBeijingChina Department of Immunology Cancer InstituteChinese Academy of Medical Science and Peking Union Medical CollegeBeijingChina Department of Hematopathology University of Texas M.D.Anderson Cancer CenterHoustonTXUSA These authors contributed equally to this work

The restriction of immunoglobulin(Ig)expression to B lymphocytes is well ***,several reports have confirmed that the Ig gene can be expressed in many non-B cancer cells and/or some normal *** aim is to determine whether the Ig gene promoter can be activated in non-B cancer cells and to identify the regulatory mechanism for Ig gene *** results show that the Ig promoter of VH4-59 was activated in several non-B cancer cell ***,two novel positive regulatory elements,an enhancer-like element at 2800 to 2610 bp and a copromoter-like element at 2610 to 2300 bp,were identified in two epithelial cancer cell lines,HeLa S3 and *** octamer element(59-ATGCAAAT-39)located in the Ig promoter,a crucial element for B-cell-derived Ig gene transcription,was also very important for non-B-cell-derived Ig gene *** importantly,we confirmed that octamer-related protein-1(Oct-1),but not Oct-2,was a crucial transcriptional factor for Ig gene transcription due to its ability to bind to the octamer element of the Ig promoter in epithelial cancer *** results suggested the presence of a distinct regulatory mechanism for Ig gene expression in non-B cancer cells.

关键词： Ig gene transcription Oct-1 promoter transcription regulation VH4-59