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Microstructural and deformational studies on mylonite in the detachment faults of Yalashangbo dome, North Himalayan domes zone

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Progress in Natural Science:Materials International 2005年第11期15卷 1005-1013页

作者： ZHANG Bo, ZHANG Jinjiang, GUO Lei and WANG Weiliang (department of geology, School of Earth and Space Sciences, Peking university, beijing 100871, china) department of geology School of Earth and Space Sciences Peking University Beijing 100871 China

The Yalashangbo dome, located at the eastern end of North Himalayan domes zone, has a geometry and structure similar to those of a metamorphic core complex. Ductile shear zones formed the detachment system around the dome and these zones are composed of garnet-bearing phyllonite, mylonitic schist, mylonitic gneiss and mylonitic granite. Ductile shear fabrics developed well in my-lonitic rocks, and penetrative lineation and foliation were formed by stretched quartz and feldspar and preferred orientation of mica. Polar Mohr diagram method is used to calculate the kinematic vorticity numbers of the shear zones in the detachment system. Results indicate that the shear zone is a thinned shear zone (thinning of 23 % ) in an extensional setting which underwent a general shear dominated by simple shear. Comparison of the vorticity numbers between the northern and southern flanks of the Yalashangbo dome shows that the dome is an asymmetric system formed by a north-northwest-directed detaching unanimously. Statistical fractal analysis shows that the shapes of dynamically recrystallized quartz grains in the mylonites have characteristics of self-similarity, with fractal numbers ranging from 1.05.to 1.18. From these fractal numbers, the strain rate of the rock was deduced from 10-9.2S-1 to 10-7.3S-1, the differential paleao-stress was 13.7-25.6 MPa during the deformation happened at a temperature over 5.0 ℃. The ductile shear zones in the detachment system around Yalashangbo dome were formed under a high green-schist grade condition or happened simultaneously with the intrusion of granite.

关键词： Yalashangbo dome ductile shear zone kinematic vorticity fractal analysis deformation temperature strain rate.

Neutron and density logging responses to gas reservoir for well-balanced and under-balanced logging:Gas reservoirs of sandstone in a western china field

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Science china Earth Sciences 2008年第S2期51卷 201-206页

作者： WU WenSheng1,XIAO LiZhi1 & ZHANG LongHai2 1 Resource & Information department,china university of petroleum,beijing 102.4.,china 2 Research Institute of petroleum Exploration and Development,Petrochina,beijing 100083,china Resource & Information department China University of Petroleum Beijing China Research Institute of petroleum Exploration and Development PetroChina Beijing China

Studying the response differences between neutron and density logging of gas reservoir for well-balanced and under-balanced logging will be of significance in evaluation of gas reservoir under the under-balanced condition and application of logging data. With Monte Carlo simulation technique,the paper obtains the relationship between neutron and density logging measurement and borehole di-ameter,porosity or gas saturation for well-balanced and under-balanced logging. The conclusions show that the response trend of under-balanced logging to gas reservoirs agrees with that of well-balanced logging with small borehole,and under-balanced logging data can be used usually as well-balanced logging data. When borehole diameter is large,under-balanced logging data should be corrected for the influences of borehole.

关键词： under-balanced logging density logging neutron logging gas reservoir response

Geochemical characteristics and origin of gases from the Upper,Lower Paleozoic and the Mesozoic reservoirs in the Ordos Basin,china

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Science china Earth Sciences 2008年第S1期51卷 183-194页

作者： HU AnPing 1 ,Li Jian 2 ,ZHANG WenZheng 3 ,LI ZhiSheng 2 ,HOU Lu 4 &LIU QuanYou 5.1 department of Earth Sciences,Zhejiang university,Hangzhou 310027,china 2 Langfang Branch,Reasearch Institute of petroleum Exploration and Development,Petrochina,Langfang 065.07,china 3 Institute of Exploration and Development,Petrochina Changqing Oilfield Company,Xi’an 710021,china 4 university of petroleum,beijing102.4.,china 5.Petrochina Research Institute of petroleum Exploration and Development,beijing 100083,china department of Earth Sciences Zhejiang University Hangzhou China Langfang Branch Reasearch Institute of Petroleum Exploration and Development PetroChina Langfang China Institute of Exploration and Development PetroChina Changqing Oilfield Company Xi’an China university of petroleum Beijing China Petrochina Research Institute of petroleum Exploration and Development Beijing China

The Ordos Basin,the second largest sedimentary basin in china,contains the broad distribution of natural gas *** far,several giant gas fields have been discovered in the Upper and Lower Paleozoic in this basin,each having over 1000×10 8 m 3 of proven gas reserves,and several gas pools have also been discovered in the *** paper collected the data of natural gases and elucidated the geochemical characteristics of gases from different reservoirs,and then discussed their *** hydrocarbons preserved in the Upper Paleozoic,the elevatedδ13C values of methane,ethane and propane indicate that the gases would be mainly coal-formed gases;the singular reversal in the stable carbon isotopes of gaseous alkanes suggests the mixed gases from humic sources with different *** the Lower Paleozoic,theδ13C 1 values are mostly similar with those in the Upper Paleozoic,but theδ13C 2 andδ13C 3 values are slightly lighter,suggesting that the gases would be mixing of coal-type gases as a main member and oil-type *** are multiple reversals in carbon isotopes for gaseous alkanes,especially abnormal reversal for methane and ethane(i.e.δ13C 1 >δ13C 2 ),inferring that gases would be mixed between high-mature coal-formed gases and oil-type *** the Mesozoic,the δ13Cvalues for gaseous alkanes are enriched in 12C,indicating that the gases are mainly derived from sapropelic sources;the carbon isotopic reversal for propane and butane in the Mesozoic is caused by microbial oxidation and mixing of gases from sapropelic sources with different *** contrast to the Upper Paleozoic gases,the Mesozoic gases are characterized by heavier carbon isotopes of iso-butane than normal butane,which may be caused by gases generated from different kerogen types. Finally,according toδ13C 1 -Ro relationship and extremely low total organic carbon contents,the Low Paleozoic gases would not be generated from the Ordovician source as a main gas source,bycontrast, the Upper Pale

关键词： Ordos Basin natural gas chemical composition carbon isotope genesis

SERIES REPRESENTATION OF DAUBECHIES' WAVELETS

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Journal of Computational Mathematics 1997年第1期15卷 81-96页

作者： X.G. Lu (department of Applied Mathematics, Tsinghua university, beijing, china) 清华大学应用数学系北京

This paper gives a kind of series represeotation of the scaling functions φNand the associated wavelets . constructed by Daubechies. Based on Poission sununation formula, the functions gh. φN(x+N-1), φN (x+N),'''' φN (x+2N-2)(Ox 1) are linearly represented by φN(x), φN(x + 1),''', φN(x + 2N - 2) and some polynomials of order less than N, and φ0(x):= (φN (x), φN (x + 1),''', φN (x + N -2))t is translated into a solution of a nonhomogeneous vectorvalued functional equationwhere A0, A1 are (N - 1) x (N - 1)-dimensional matrices, the components of P0(x), P1 (x) are polynomials of order less than N. By iteration, .φ0(x) is eventualy represented as an (N - 1)-dimensional vector series with vector norm where and

关键词： Pro ER Math Si WAVELETS SERIES REPRESENTATION OF DAUBECHIES

The formation depth of coesite-bearing eclogite,Dabie UHPM zone,china,modified by tectono-original additional hydrostatic pressure

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Chinese Science Bulletin 1999年第5期44卷 398-411页

作者： LU Guxian, CHEN Jing, LIU Ruixun and LI Xiaobo Institute of Geomechanics , beijing 100081, china Electron Microscopy Laboratory, Peking university, beijing 100871, china {5. of geology, Peking university, beijing 100871, china Institute of Geological Information , beijing 100037, china Institute of Geomechanics Beijing China Electron Microscopy Laboratory Peking University Beijing China department of geology Peking University Beijing China Institute of Gelogical Information Beijing China

The knowledge that hydrostatic pressure is equal to the gravity value of the overlying rocks in studying a dynamic state of certain underground site is argued. It is suggested that the stress field T in the crust is a combination or superposition of total hydrostatic pressure P with differential stress σ,and the total hydrostatic pressure P at any point in the crust comprises two parts: one is spherical stress tensor PG caused by the gravity, and the other is spherical stress tensor Ps caused by tectonic stress; therefore P could not be attributed to the gravity of overlying rocks only. The results obtained by a finite-element simulation indicate that the tectono-original additional hydrostatic pressures Ps decrease gradually from the compressive zone （pcS） to the shear zone (PSHs)and to the tensile zone （PTs）, i.e.Pcs>PsHs>PTs in the same depth. On the basis of the above-mentioned research, the method of measurement and calculation of metallogenetic depth corrected by Ps is

关键词： formation depth tectonic additional hydrostatic pressure Dabie UHPM zone coesite-bearing eclogite expansion-cracking texture tectonic physicochemistry.

Progress in the study of molecular organized assemblies by dielectric relaxation spectroscopy

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Progress in Natural Science:Materials International 2006年第3期16卷 221-230页

作者： ZHAO Kongshuang, HE Kejuan and WEI Suxiang (department of Chemistry, beijing Normal university, beijing 100875. china department of Chemistry, South china Normal university, Guangzhou 5.0631, china) department of Chemistry Beijing Normal University Beijing 100875 China department of Chemistry South China Normal University Guangzhou 510631 China

Because dielectric spectroscopy covers a great many problems in physical and chemical systems occurring in an extremely wide frequency range, the study of this method plays an important role in physical chemistry. As an effective tool to detect inner properties of substance systems, the dielectric spectroscopy method is widely used in chemical systems and has been dramatically developed in recent decade. This review paper describes the applications of the dielectric spectroscopy in the chemical field, and main concentrations are focused on the micelle, microemulsion and other so-called molecular organized assemblies. Some dielectric principles and models proposed for these systems are introduced. In addition, recent technical developments in dielectric spectroscopy and developing trend of this method in other chemical systems are reviewed.

关键词： dielectric relaxation micelle microemulsion vesicle relaxation time.

FRACTAL RESEARCH ON CRACKS PROPAGATION OF GAS PIPELINE X5. STEEL WELDING LINE UNDER HYDROGEN ENVIRONMENT

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Acta Metallurgica Sinica(English Letters) 2001年第3期14卷 219-226页

作者： S.H. Dong , Y.M. Lu, Y. Zhang and Q. Wu (Mechanics Electronic department, university of petroleum, beijing 102200, china) (department of Material Physics, {5. of Science and Technology beijing, beijing 100083, china) (Yan Shan {5., Qinhuangd Dept. of Mech. Electron. Univ. of Pet. Beijing 102200 China

Based on the theory of hydrogen enhanced localized plasticity of the hydrogen induced cracking and the consideration of the effect of the residual stress produced by eliminated stress heat-treatment, a fractal model of hydrogen induced cracking was presented, and the relationships among the effective surface energy (H), fractal dimension D and stress intensity factor of hydrogen induced cracking, KIH, for welding pipeline under hydrogen environment was set up, from which the relationship of D and KISCC was obtained. The model has been verified experimentally to be correct.

关键词： Crack initiation Electric arc welding Environmental impact Fractals Hydrogen

Mossbauer　Spectra　of　Valleriite　from　china

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北京大学学报(自然科学版) 1997年第2期 40-45页

作者： QIN Shan CAO Zhengmin CHEN Yanjing (department of geology, Peking university, beijing, 100871, china)

在墨铜矿的结构中，Ｆｅ离子可占据硫化物层中四面体和氢氧化物层的八面体两种配位位置。穆斯堡尔谱结果表明：高自旋的Ｆｅ２＋占据四次配位位置，同质异能位移为０．４２～０．４８ｍｍｓ－１、四极分裂为０．８１～１．２８ｍｍｓ－... 详细信息

在墨铜矿的结构中，Ｆｅ离子可占据硫化物层中四面体和氢氧化物层的八面体两种配位位置。穆斯堡尔谱结果表明：高自旋的Ｆｅ２＋占据四次配位位置，同质异能位移为０．４２～０．４８ｍｍｓ－１、四极分裂为０．８１～１．２８ｍｍｓ－１；低自旋的Ｆｅ３＋占据六次配位位置，同质异能位移为０．３２～０．３６

关键词：墨铜矿穆斯堡尔谱配位

A BATCH ARRIVAL RETRIAL QUEUE WITH STARTING FAILURES,FEEDBACK AND ADMISSION CONTROL

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Journal of Systems Science and Systems Engineering 2010年第3期19卷 306-320页

作者： Jinting WANG Peng-Feng ZHOU department of Mathematics,School of Science,beijing Jiaotong university,beijing,china department of Mathematics School of Science Beijing Jiaotong University Beijing China

This paper is concerned with the analysis of a feedback M^[X]/G/1 retrial queue with starting failures and general retrial times. In a batch, each individual customer is subject to a control admission policy upon arrival. If the server is idle, one of the customers admitted to the system may start its service and the rest joins the retrial group, whereas all the admitted customers go to the retrial group when the server is unavailable upon arrival. An arriving customer （primary or retrial） must turn-on the server, which takes negligible time. If the server is started successfully （with a certain probability）, the customer gets service immediately. Otherwise, the repair for the server commences immediately and the customer must leave for the orbit and make a retrial at a later time. It is assumed that the customers who find the server unavailable are queued in the orbit in accordance with an FCFS discipline and only the customer at the head of the queue is allowed for access to the server. The Markov chain underlying the considered queueing system is studied and the necessary and sufficient condition for the system to be stable is presented. Explicit formulae for the stationary distribution and some performance measures of the system in steady-state are obtained. Finally, some numerical examples are presented to illustrate the influence of the parameters on several performance characteristics.

关键词： Batch arrival feedback repair retrial queue starting failure