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THE CHARACTERISTICS OF REMOTE SENSING TECTONICS IN QIANGTANG-CHANGDU MASSIF, QINGHAI-TIBET PLATEAU

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地学前缘 2000年第S1期7卷 435-437页

作者： Zhao Zhengzhang 1,Ye Hefei 2.Li Yongtie 2.1 china National Petroleum corporation, Beijing 10072.,{4. 2.Research Institute of Petroleum Exploration and {2., CNPC, Beijing 100083.{4.)

The northern Tibet plateau is the core of generalized Qinghai—Tibet plateau. The main part of Qiangtang—Changdu massif, which is 4.×10 4.m 2.and more than 5000m in altitude, conforms to the northern Tibet plateau in area.1 The shape features and boundary conditions of Qiangtang—Changdu massif\;(1) Qiangtang—Changdu massif shows huge flat\|lying “S” area In MSS7 mosaic image, Qiangtang—Changdu massif extends in west and east, and appears a long\|elliptic huge block composed of feathered and dendritic textures.. Noticeably, there are two similar texture “tails" in the west and east ends of the massif. The western tail turns and constringes to the north, and eastern tail to the south. Thereby, the massif shows huge “S" area. According to the regional analysis, the eastern tail locates between Shaluli Mt.\|Taniantaweng Mt. and Mujiang River, and western part through Bangong\|co connects with Pamirs along Karakoram Mt. In regional tectonics, the massif locates between Lazhulong\|Xijinwulan\|co\|Jinshajiang River and Bangong\|co\|Dongqiao\|Nujiang River fault belts.

关键词： Qiangtang—Changdu massif remote sensing boundary condition circular structure deformin g features mechanic characteristic dynamics

Structures of ovary and ovarian follicle in flathead lobster,Thenus orientalis (Lund, 1793. (Crustacea: Decapoda: Scyllarida)

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Acta Oceanologica Sinica 2001年第2期20卷 241-250页

作者： Zhu Dongfa, Li Shaojing, Wang Guizhong (1. Department of Oceanography, Xiamen University, Xiamen 3.1005, china 2. Faculty of Life Science and Biotechnology, Ningbo University, Ningbo 3.52.1, china) Department of Oceanography Xiamen University Faculty of Life Sci./Biotechnology Xiamen 361005 China

The ovary contains four morphological components: (1) the ovarian wall, (2. the reproductive epithelium, (3. the cellular layer containing oocytes, oogonia (especially for early-developing ovary) and follicle cells, and (4. the extensions of the ovarian wall. The ovarian wall and its extensions consist of blood vessels, sinuses, muscle cells and others. The extensions of the ovarian wall project into among the follicles and insert on the thick basal membrane of each follicle. From inside to outside, the follicles are composed of four parts: (1) the oocyte, (2. the perivitelline space, (3. the follicle cells, and (4. the basal membrane. The surface of the oocyte during vitellogenesis is folded into numerous long microvilli that project into the perivitelline space between the oocyte surface and the bace of the follicle cell layer. In addition, the plasma membrane of the vitellogenic oocyte contains many pinocytotic pits. The perivitelline space is engorged with with more electron- denser {2. as the development of the follicle. The inclusion of perivitelline space in the mature follicle is named specially as the chorine. The chorion is composed of two region, a thinner exochorion and a thicker endochorion containing electron-dense granular {2.. The follicle cell layer is composed of a single layer of polygonal follicle cells which exhibit higher synthetic activity. The synthetic product of the follicle cell layer is one scarce for the inclusion of the perivitelline space. The structures of the ovary and ovarian follicle in T. orientalis show that the exogenously biosyn- thetic yolk plays important roles in the vitellogenesis.

关键词： Thenus orientalis ovary follicle chorion formation

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油气井固井二界面封固系统及其破坏模型

天然气工业 2006年第7期26卷 74-76页

作者：顾军高兴原刘洪中国地质大学中国石油吉林油田钻井技术服务公司重庆科技学院武汉

油气井固井二界面封隔能力问题是一个亟待解决的复杂性工程难题,它会直接影响勘探开发的效果和效益。文章从油气田开采的角度,提出了固井二界面封固系统的概念,分析了系统组分对固井二界面封固系统的作用和影响,完善了系统的状态变化模... 详细信息

油气井固井二界面封隔能力问题是一个亟待解决的复杂性工程难题,它会直接影响勘探开发的效果和效益。文章从油气田开采的角度,提出了固井二界面封固系统的概念,分析了系统组分对固井二界面封固系统的作用和影响,完善了系统的状态变化模型和动态破坏模型。研究认为,固井二界面封固系统是由5个间歇界面,即纯水泥浆与受污染水泥浆之间的界面、受污染水泥浆与死泥浆之间的界面、死泥浆与水泥饼之间的界面、水泥饼与滤饼之间的界面和滤饼与地层壁面之间的界面和4.不同物质组成的复合体,其中死泥浆是指注替过程中无法或难以参与循环的那部分老化物质,滤饼是滤饼和水泥饼的组合。因此,固井二界面问题的研究和解决必须要从系统的角度出发,才能从根本上解决固井二界面的胶结问题。

关键词：油气井固井二界面封固系统组成破坏模型

Structural and Electrical Properties of Cu Films by dc Biased Plasma-Sputter-Deposited on MgO(001)

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Journal of University of Science and Technology Beijing 2001年第3期8卷 207-209页

作者： Hong Qiu, Yue Tian, Mituru Hashimoto Applied Science School, University of Science and Technology Beijing, Beijing 100083. china Beijing Keda-Tianyu Microelectronic {2. Technology development corporation, 3. Xueyuanlu, Haidian District, Beijing 10008 Univ Sci & Technol Beijing App Sci Sch Beijing 100083 Peoples R China Beijing Keda Tianyu Microelect Mat Technol Dev co Beijing 100083 Peoples R China Univ Electrocommun Dept Appl Phys & Chem Chofu Tokyo 1828585 Japan

Cu films of3.nm and 15 nm thick were deposited on MgO(001) substrates at 185℃ by dc plasma-sputtering at 1.9kv and 8 mA in pure Ar gas. A dc bias voltage Vs, of 0 V or -80 V was applied to the substrate during deposition. Structural and electrical proper-ties have been investigated by cross-sectional transmission electron microscopy (XTEM), high resolution XTEM (XHRTEM) and by measuring temperature coefficient of electrical resistance (TCR;η) in the temperature interval of-13.℃ to 0 ℃. The Cu film is pol- ycrystalline at Vs= 0 V while it epitaxially grows with Cu(00 )|| MgO(00 1) and Cu[0 10] || MgO[010] at Vs,=-80 V. However, the latter has a very rough surface. The change of η with film thickness and Vs is interpreted in terms of the structure change. Misfit dislocations and lattice expansion are induced along the MgO surface to relax the strain energy due to the lattice mismatch between Cu and MgO.

关键词： Cu film biased plasma-sputter-deposition misfit dislocations TCR XHRTEM

The susceptibility of ventricular arrhythmia to aconitine in conscious Lyon hypertensive rats

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Acta Pharmacologica Sinica 2007年第2期28卷 211-215页

作者： Min LI~(2.3. Jin WANG~2.He-hui XIE~2.Fu-ming SHEN~2.Ding-feng SU~(2.4.2.Department of Pharmacology,Second Military.Medical University,Shanghai 2.04.1},{2. 3.Department of Pediatrics,Shanghai Tenth People's Hospital,Tongji University,Shanghai 2.0072.{2. DepartmentofPharmacology SecondMilitaryMedicalUniversityShanghai200433China DepartmentofPediatrics ShanghaiTenthPeople'sHospitalTongjiUniversityShanghai200072China

Aim:The present work was designed to investigate the relationship betweenhemodynamic parameters and the susceptibility of ventricular arrhythmia toaconitine in conscious Lyon hypertensive rats(LH).Methods:Male LH and Lyonlow blood pressure rats(LL)were *** the determination of baroreflexsensitivity(BRS),ventricular arrhythmia was induced by aconitine infusion inconscious *** pressure(BP)was recorded during the period of ***:compared with the LL rats,the LH rats possessed significantly higherBP,blood pressure variability and lower *** threshold of aconitine requiredfor ventricular fibrillation and cardiac arrest in the LH rats were significantly lowerthan those in the LL *** was found that all the hemodynamic parametersstudied were not correlated with the threshold of aconitine required for arrhythmia,with the exception of BRS,which was positively related to the threshold ofaconitine required for ventricular premature ***:The LH rats pos-sessed greater susceptibility to aconitine-induced ventricular arrhythmias whencompared to the LL *** greater susceptibility could not be attributed to anyone of the hemodynamic parameters alone studied in the LH *** is proposedthat various hypertension-associated abnormalities,including the abnormalhemodynamics,may co-contribute to this vulnerability to ventricular arrhythmias.

关键词： arrhythmia aconitine baroreflex sensitivity hypertension Lyon hypertensive rats

A statistical model for porous structure of rocks

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Science china(Technological Sciences) 2008年第11期51卷 2040-2058页

作者： JU Yang1,2. YANG YongMing1, SONG ZhenDuo3.& XU WenJing4.1 State Key Laboratory of coal Resources and Safe Mining, china University of Mining & Technology, Beijing 100083. china 2.Department of Mechanical and Manufacturing Engineering, The University of Calgary, 2.00 University Drive NW Calgary, AB T2. 1N4. Canada 3.0} National coal Mining Equipment co. {3., Beijing 100011, china 4.Department of materials and Metallurgy, The University of Utah, Salt Lake City, Utah 84.12. USA State Key Laboratory of coal Resources and Safe Mining China University of Mining & Technology Beijing 100083 China Department of Mechanical and Manufacturing Engineering The University of Calgary 2500 University Drive NW Calgary Calgary AB T2N 1N4 Canada china National coal Mining Equipment co. ltd Beijing 100011 China Department of materials and Metallurgy The University of Utah Salt Lake City Utah 84112 USA

The geometric features and the distribution properties of pores in rocks were in- vestigated by means of CT scanning tests of sandstones. The centroidal coordi- nates of pores, the statistic characterristics of pore distance, quantity, size and their probability density functions were formulated in this paper. The Monte Carlo method and the random number generating algorithm were employed to generate two series of random numbers with the desired statistic characteristics and prob- ability density functions upon which the random distribution of pore position, dis- tance and quantity were determined. A three-dimensional porous structural model of sandstone was constructed based on the FLAC3. program and the information of the pore position and distribution that the series of random numbers defined. On the basis of modelling, the Brazil split tests of rock discs were carried out to ex- amine the stress distribution, the pattern of element failure and the inosculation of failed elements. The simulation indicated that the proposed model was consistent with the realistic porous structure of rock in terms of their statistic properties of pores and geometric similarity. The built-up model disclosed the influence of pores on the stress distribution, failure mode of material elements and the inosculation of failed elements.

关键词： porous structure statistical model random numbers reconstruction rocks

Aberrant histone H4.acetylation in dead somatic cell-cloned calves

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Progress in Natural Science:materials International 2008年第7期18卷 813-818页

作者： Lei Zhang a,b,*, Shaohua Wang a, Qiang Li a, Xiangdong Ding c, Yunping Dai a, Ning Li a,* a State Key Laboratory for Agrobiotechnology, china Agricultural University, Beijing 100094. china b Beijing Gene & Protein Biotechnology co. {2., Beijing 100094. china c college of Animal Science and Technology, china Agricultural University, Beijing 100094. china State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100094 China Beijing Gene & Protein Biotechnology co. ltd Beijing 100094 China college of Animal Science and Technology China Agricultural University Beijing 100094 China

In somatic cell-cloned animals, inefficient epigenetic reprogramming can result in an inappropriate gene expression and histone H4.acetylation is one of the key epigenetic modifications regulating gene expression. In this study, we investigated the levels of histone H4.acetylation of 11 development-related genes and expression levels of 19 genes in lungs of three normal control calves and nine aber- rant somatic cell-cloned calves. The results showed that nine studied genes had decreased acetylation levels in aberrant clones (p 0.05). Whereas 13.genes had significantly decreased expression (p controls and clones (p > 0.05), and only one gene had higher expression level in clones (p 4.acetylation and expression in aberrant clones than in controls, and the level of histone H4.acetylation was even more lowered in aberrant clones than those in controls. It was suggested that the lower levels of histone H4.acetylation in aberrant clones caused by the previous memory of cell differentiation might not support enough chromatin reprogramming, thus affecting appropriate gene expressions, and growth and development of the cloned calves. To our knowledge, this is the first study on how histone H4.acetylation affects gene expression in organs of somatic cell-cloned calves.

关键词： Somatic cell-cloned calves Histone H4.acetylation Gene expression Lungs

In Vitro Cytotoxicity of Polyphosphoester as a Novel Injectable Alveolar Replacement material

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2008年第5期28卷 604-607页

作者：张智星毛靖冯祥礼肖建中邱进俊 Department of Orthodontics Tongji HospitalTongji Medical College Huazhong University of Science and Technology Department of Nursing Tongji Medical College Huazhong University of Science and Technology college of materials Science and Engineering Huazhong University of Science and Technology college of Chemistry Huazhong University of Science and Technology

The aim of this study was to investigate the in vitro cytotoxicity of polyphosphoester polymer used as a novel injectable alveolar bone substitutes for controlled delivery of tetracycline. Cell culture medium was exposed to the polymer （0.01-10 mg/mL） for 2. h. The L-92. mouse fibro- blasts were then exposed to the treated cell culture medium for 2. h. Finally, cell viability and growth were assessed by using MTT assay and Alamar Blue assay. No significant cytotoxicity of the polyphosphoester against L-92. mouse fibroblasts was observed at a concentration up to 10 mg/mL （P〉0.05）. The two evaluation methods showed no significant differences （P〉0.05）. This study suggests that polyphosphoester does not demonstrate any significant toxic effects to cells in vitro and has the potential to be used both as a medical device and as scaffolds in tissue engineering applications.

关键词： polyphosphoester cytotoxicity MTT assay Alamar Blue test

Estimation of the Passive Earth Pressure with Inclined cohesive Backfills:the Effect of Intermediate Principal Stress is considered

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Estimation of the Passive Earth Pressure with Inclined Cohes...