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Mechanism for calcite dissolution and its contribution to development of reservoir porosity and permeability in the Kela 2 gas field,Tarim Basin,china

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Science china Earth Sciences 2008年第4期51卷 567-578页

作者： YU BingSong1.3. DONG HailLiang2,3.& RUAN Zhuang1.3.1.State Key Laboratory of Geological Processes and Mineral Resources, china university of geosciences, Beijing {3., china 2 Department of Geology, Miami university,Oxford, OH 45056, USA 3.Geomicrobiology Laboratory, china university of geosciences, Beijing, {3., china State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Department of Geology Miami University Oxford OH 45056 USA Geomicrobiology Laboratory China University of Geoscien

This study is undertaken to understand how calcite precipitation and dissolution contributes to depth-related changes in porosity and permeability of gas-bearing sandstone reservoirs in the Kela 2 gas field of the Tarim Basin, Northwestern china. Sandstone samples and pore water samples are col-lected from well KL201.in the Tarim Basin. Vertical profiles of porosity, permeability, pore water chem-istry, and the relative volume abundance of calcite/dolomite are constructed from {1.00 to 4000 m below the ground surface within major oil and gas reservoir rocks. Porosity and permeability values are in-versely correlated with the calcite abundance, indicating that calcite dissolution and precipitation may be controlling porosity and permeability of the reservoir rocks. Pore water chemistry exhibits a sys-tematic variation from the Na2SO4 type at the shallow depth ({1.00-{1.{1. m), to the NaHCO{1.type at the intermediate depth ({1.{1.―{1.95 m),and to the CaCl2 type at the greater depth ({1.28―{1.{1. m). The geochemical factors that control the calcite solubility include pH, temperature, pressure, Ca2+ concen-tration, the total inorganic carbon concentration (ΣCO2), and the type of pore water. Thermodynamic phase equilibrium and mass conservation laws are applied to calculate the calcite saturation state as a function of a few key parameters. The model calculation illustrates that the calcite solubility is strongly dependent on the chemical composition of pore water, mainly the concentration difference between the total dissolved inorganic carbon and dissolved calcium concentration (i.e., [ΣCO2] -[Ca2+]). In the Na2SO4 water at the shallow depth, this index is close to 0, pore water is near the calcite solubility. Calcite does not dissolve or precipitate in significant quantities. In the NaHCO{1.water at the intermedi-ate depth, this index is greater than 0, and pore water is supersaturated with respect to calcite. Massive calcite precipitation was observed at this depth interval and

关键词： calcite dissolution porosity thermodynamic Tarim Basin

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Direct CP violation in hadronic B decays

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Science china(Physics,Mechanics & Astronomy) 2006年第3期49卷 357-366页

作者： HONG Bihai1.2 & Lü Caidian3.1. Department of Physics, Lishui {1., Lishui 3.3.00,china 2. Department of Physics, Shanghai Jiaotong {1., Shanghai 20003.,{3. 3. Institute of High Energy Physics, Beijing 1.0049,china Department of Physics Lishui University Lishui 323000 China Department of Physics Shanghai Jiaotong University Shanghai 200030 China Institute of High Energy Physics Beijing 100049 China

There are different approaches for the hadronic B decay calculations, recently. In this paper, we upgrade three of them, namely factorization, QCD factorization and the perturbative QCD approach based on kT factorization, using new parameters and full wave functions. Although they get similar results for many of the branching ratios, the direct CP asymmetries predicted by them are different, which can be tested by recent experimental measurements of B factories.

关键词： CP violation hadronic B decay factorization.

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Ev Surge Illuminates Pathto Sustainable Mobility

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中印对话（英文版） 2024年第1期38卷 56-58页

作者： china-lndia Dialogue 不详

china's Booming NEVs zhang Yifan occupation:PhD student at the school of Philosophy,Renmin {1. of china Birth Place:Panzhihua,Sichuan Current Residence:Lijiang,Yunnan Rapid advancements in technological innovation and energy transformation within the automotive industry in recent years have far exceeded *** market share of new energy vehicles(NEVs)in the automotive sector continues to grow,with globally recognized brands like Tesla and domestically acclaimed brands such as Xiaomi frequently capturing the public's attention.

关键词： Sustainable occupation globally

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Progress and review of the studies on the end-Triassic mass extinction event

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Science china Earth Sciences 2005年第12期48卷 2049-2060页

作者： DENG Shenghui1.2, LU Yuanzheng1.2,3.& XU Daoyi4 1. Research Institute of Petroleum Exploration and Development, Beijing {1., china 2. Key Laboratory of Oil and Gas Reservoir of Petrochina, Beijing {1., china 3. china university of geosciences, Beijing {1., china 4. Institute of Geology, china Earthquake Administration, Beijing 1.0029, china 1. Research Institute of Petroleum Exploration and Development 100083 Beijing China 2. Key Laboratory of Oil and Gas Reservoir of Petrochina 100083 Beijing China 3. china university of geosciences 100083 Beijing China 4. Institute of Geology China Earthquake Administration 100029 Beijing China

The mass extinction at the end-Triassic is one of the five biggest in the Phanerozoic. However,it is the least well understood among these five events, and only till last decade it became a great academic interesting subject to geologists. The evidences for this event come obviously from bivalves, brachiopods, ammonites, corals, radiolaria, ostracods and foraminifera of marine habitats, and plants and tetrapods of terrestrial realm. By contrast, for some of other groups, such as marine gastropods and marine vertebrates, no mass extinction has been recog-nized yet. The extinction event is strongly marked at specific level but shown a complicated situa-tion at generic and family levels. Dramatic changing of the environment, such as the temperature raise due to the greenhouse effect, the marine anoxic habitats caused by a sudden transgression after the regression at the end of Triassic, has been claimed to be the main cause of the extinction. Many hypotheses have been suggested to demonstrate the mechanisms of the environment changing, among which two popular ones are the bolide impact and volcanic eruption. The Triassic-Jurassic (Tr-J) boundary mass extinction event is still poorly understood because no enough data have been obtained from the Tr-J boundary successional sections of both marine and terrestrial sediments, and most of these studies were regionally restricted. The basic aspects of the event and its associated environmental conditions remain poorly characterized and the causal mechanism or mechanisms are equivocal. Some authors even doubt its occurrence. china has many successionally developed terrestrial and marine Tr-J sections. Detailed studies of these sections may be important and significant for well understanding of the event.

关键词： progress, review, end-Triassic, mass extinction, mechanism, Tr-J boundary.

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Online uniform machine covering with the known largest size

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Progress in Natural Science:Materials International 2007年第11期17卷 1271-1278页

作者： Cao Shunjuan1.2 and Tan Zhiyi1.3.1. Department of Mathematics, Zhejiang {1., Hangzhou 3.0027, china 2. Department of Mathematics, Zhejiang Forestry {1., Hangzhou 3.1.0}0, china 3. State Key Laboratory of CAD & CG, Zhejiang {1., Hangzhou 3.0027, china) Department of Mathematics Zhejiang University Hangzhou 310027 China Department of Mathematics Zhejiang Forestry University Hangzhou 311300 China State Key Laboratory of CAD & CG Zhejiang University Hangzhou 310027 China

This paper investigates the semi-online scheduling problem with the known largest size on two uniform machines. The objective is to maximize the minimum machine completion time. Both lower bounds and algorithms are given. Algorithms are optimal for the majority values of s≥1. where s is the speed ratio of the two machines. The largest gap between the competitive ratio and the lower bound is about 0.064. Moreover, the overall competitive ratio 2 matches the overall lower bound.

关键词： scheduling and covering uniform machine design and analysis of algorithm online competitive ratio

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Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South china

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Science china Earth Sciences 2006年第3期49卷 225-241页

作者： ZUO Jingxun1.2, TONG Jinnan3. QIU Haiou4 & ZHAO Laishi3.1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 21.008, china 2. Henan Institute of Geological Survey, Zhengzhou 450007, china 3. State Key Laboratory of Geological Processes and Mineral Resources at china {3. of geosciences, Wuhan 43.074, china 4. Faculty of Material Sciences and Chemical Engineering, china {3. of geosciences, Wuhan 43.074, china 1. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Henan Institute of Geological Survey Zhengzhou 450007 China 3. State Key Laboratory of Geological Processes and Mineral Resources at{1. university of geosciences Wuhan 430074 China 4. Faculty of Material Sciences and Chemical Engineering China University of Geosciences Wuhan 430074 China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South china, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 1.1. background values are intensively controlled by palaeogeographic environment. In general, δ 1.1. values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze Region.

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Geothermal and fluid flowing simulation of ore-forming antimony deposits in Xikuangshan

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Science china Earth Sciences 2006年第8期49卷 862-871页

作者： YANG Ruiyan1.2, MA Dongsheng2, BAO Zhengyu3. PAN Jiayong2, CAO Shuanglin2 & XIA Fei2 1. School of Mathematics and Physics,{1. university of geosciences, Wuhan 43.074,{1. 2. State Key Laboratory for Research of Mineral Deposits, Nanjing university, Nanjing 21.093.{1. 3. Faculty of Earth Sciences,{1. university of geosciences, Wuhan 43.074,{1. 1. School of Mathematics and Physics China University of Geosciences Wuhan 430074 China 2. State Key Laboratory for Research of Mineral Deposits Nanjing University Nanjing 210093 China 3. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

The Xikuangshan Antimony Deposit located in the Mid-Hunan Basin, china, is the larg- est antimony deposit in the world. Based on the hydrogeological and geochemical data collected from four sections, Xikuangshan-Dajienao (AO), Xikuangshan-Dashengshan (BO), Xikuang- shan-Longshan (CO) and Dafengshan (DO) in the Basin, an advanced metallogenic model related to deep-cyclic meteoric water of Xikuangshan Antimony Deposit is put forward in this paper using a model of heat-gravity-driving fluid flow transportation. The simulation results show that the ore-forming fluid of the deposit mainly comes from the Dashengshan and Longshan areas where BO and CO sections are located if the overall basin keeps a constant atmospheric precipitation and infiltration rate during mineralization, and that the average transportation speed of the ore-forming fluids is about 0.2―0.4 m/a.

关键词： ore-forming fluid, numerical simulation, geothermal field, geofluid transport, Xikuangshan, antimony deposits.

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Mineralogy and crystal structure determination of Mg-fillowite

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Science china Earth Sciences 2005年第5期48卷 635-646页

作者： MA Zhesheng 1., SHI Nicheng 1.& YE Danian 2 1. china {1. of geosciences, Beijing {3., china 2. Institute of Geology, Chinese Academy of Sciences, Beijing 1.0029, china 1. china {1. of geosciences 100083 Beijing China 2. Institute of Geology Chinese Academy of Sciences 100029 Beijing China

Accurate crystal structure determination of complex phosphate Mg-fillowite ? Na2Ca(Mn4Mg2Fe)7[PO4]6 has been finished. Mg-fillowite occurs in muscovite-pegmatite in the Altay area, Xinjiang, china. It is of the trigonal lattice, with space group R-{1. unit cell a=1.51.{1.{1. nm, c=4.{1.91.2) nm, V=8.57{1. nm{1. Z = 1.. The R-factor of the determination accuracy is R (I > 2σ ( I )) = 0.0776. The cationic polyhedra consist of two kinds of structural units: compound col- umn and screw column. In three-dimensional space, they are linked with each other through corner sharing or edge sharing to build the entire structure. There are 45 atoms in an asymmetric unit and 720 atoms in a unit cell. In terms of types and connection manners of the coordination polyhedra, the degree of complicity is rarely seen in all mineral crystal structures. Study of such a structure is significant for the classification of phosphate and the building rule of coordination polyhedra in a complex crystal structure.

关键词： Mg-fillowite, complex phosphate, crystal structure, coordination polyhedron.

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The species diversity of fusulinaceans and high-frequency sea-level changes in the Carboniferous-Permian boundary section at Xikou, Zhen'an County,Shaanxi Province, china

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Science china Earth Sciences 2006年第7期49卷 673-683页

作者： ZHANG Haijun1. WANG Xunlian2, DING Lin1. XIA Guoying3.& WANG Lei2 1. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 1.0085,{1. 2. Faculty of Earth Sciences and Mineral Resources,{1. university of {3., Beijing 1.0083,{1. 3. Tianjin Institute of Geology and Mineral Resources, Tianjin 3.01.0,{1. 1. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Faculty of Earth Sciences and Mineral Resources China University of Geosciences Beijing 100083 China 3. Tianjin Institute of Geology and Mineral Resources Tianjin 300170 China

The study on the interrelation between sea-level changes and biodiversity with its evolu-tion has great significance for understanding the impact of global changes on organic evolution and exploring the inherent laws of life-environment coevolution in geological history. In this paper, the stratigraphic distribution of fusulinacean fauna in the Carboniferous-Permian boundary section at Xikou, Zhen’an County, Shaanxi Province, is analyzed quantitatively, and the relationship between the species diversity of fusulinaceans and relative sea-level changes is discussed. As a whole, the spe-cies numbers of fusulinacean fauna experience a rapid increase and an obvious decline in Xikou, Zhen’an County, from the Late Carboniferous to the Early Permian. There is a significant increase in species diversity around the Carboniferous-Permian boundary, which is one of the biggest bio-events of the fusulinacean fauna, and represents the radiation of Pseudoschwagerininae subfamily in the studied area. Integrated fusulinacean species diversity into sequence stratigraphic framework, de-tailed study suggests that the species diversity of the fusulinaceans is closely related to its relative stratigraphic location, and is essentially controlled by the sea-level changes, especially by the high-frequency sea-level changes. Generally, the species diversity of fusulinaceans is low, and the number of first and last appearance datum is small in the lower unit of high-frequency depositional cycle formed during the quick rise of the sea level; whereas the species diversity of fusulinaceans is high, and the number of first and last appearance datum is large in the upper unit of high-frequency cycle formed during the slow fall of the sea level. Within the third-order depositional sequence, the species diversity of the fusulinaceans at the first flooding surfaces and the maximum flooding surfaces is low, and it increases upward. The fusulinacean species diversity is low within the transgressive syst

关键词： fusulinaceans, species diversity, high-frequency cyclothem, sequence stratigraphy, sea-level changes, Carboniferous-Permian boundary, Zhen'an, Shaanxi.

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Real-World Treatment Adherence to Smoking Cessation Medications and Association with Treatment Outcome—27 Centers,china,201.–2022

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china CDC weekly 2024年第22期6卷 522-529,I0001-I0003页

作者： Anqi Cheng Zhao Liu Xinmei Zhou Zheng Su Dan Xiao Chen Wang the china National Tobacco Cessation Cohort Study(CNTCCS)Study Group Department of Tobacco Control and Prevention of Respiratory Disease Center of Respiratory MedicineChina-Japan Friendship Hospital/WHO Collaborating Center for Tobacco Cessation and Respiratory Diseases Prevention/National Center for Respiratory Medicine/National Clinical Research Center for Respiratory Diseases/Institute of Respiratory MedicineChinese Academy of Medical SciencesBeijingChina Department of Pulmonary and Critical Care Medicine Center of Respiratory MedicineChina-Japan Friendship Hospital/WHO Collaborating Center for Tobacco Cessation and Respiratory Diseases Prevention/China National Center for Respiratory Medicine/China National Clinical Research Center for Respiratory DiseasesBeijingChina Chinese Academy of Medical Sciences and Peking Union Medical College BeijingChina 不详

What is already known about this topic?Medication non-adherence significantly impedes smoking cessation *** effective smoking cessation medications are accessible in china,realworld adherence and its correlation with treatment outcomes remain largely *** is added by this report?From December 201. to January 2022,1.1.0 participants were recruited from 27 centers in all seven geographical regions of *** revealed that only {1..2%of smokers adhered to the prescribed 1.-week smoking cessation treatment and those with a higher education level were more likely to be *** addition,smokers with good adherence were more likely to successfully quit *** are the implications for public health practice?The data obtained could enhance our understanding of smoking cessation practices in *** adherence is a crucial strategy to enhance the effectiveness of smoking cessation treatments and management provided to smokers.

关键词： china smoke likely

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