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Acta Geologica Sinica(English Edition) 1993年第4期67卷 403-410页

作者： Lu Qi, Lei Xinrong and Liu Huifang china university of geosciences, wuhan, Hubei china university of geosciences Wuhan Hubei

There are two aspects in the study of irregular mixed-layer clay minerals: one is the kinds and ratios of their basic structural unit layers and the other is the junction probabilities of the unit layers. Irregular mixed-layer illite/smectite clay minerals (I/S) are widespread in nature. While studying the clay minerals from the Permian-Triassic (P/T) boundary bed, the authors found that I/S clay minerals are developed in all P/T boundary clay layers in areas from the northwest to southeast of china. Systematic mineralogical studies of the I/S clay minerals from Hunan, Hubei, Sichuan and Zhejiang were made by means of X-ray, infrared spectroscopic, electron microscopic and chemical analyses and a deepened study of the stacking sequences of their structural unit layers was conducted by the MacEwan one—dimentional direct Fourier transform. It was found that the stacking of the illite and smectite crystal layers along the c axis can be derived from Fibonacci sequences. Hence, the authors propose that such I/S clay minerals are possessed of two—dimentional crystal lattice and one—dimentional quasicrystal lattice.

关键词： mixed-layer illite/smectite clay minerals P/T boundary MacEwan direct Fourier transform quasicrystal lattice particle fractional dimension

The Dynamic Mechanisms for the Formation of Primary Metal Zoning of Cassiterite-Sulfide Deposits in the Gejiu Metallogenic Province, Yunnan

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Acta Geologica Sinica(English Edition) 1991年第1期65卷 51-63页

作者： Yu Chongwen Jiang Yaosong china university of geosciences, Beijing china university of geosciences Beijing

Copper and tin in cassiterite-sulfide deposits of the Gejiu metallogenic province are intimately associatedand show peculiar primary metal zoning. The authors made use of computer techniques to simulatenumerically the zoning of these ore deposits. The study shows that the regular spatial zoning probably resultedfrom the succession of multiple, intermittent and pulsatory mineralizations, The successive transports with di-verse velocities along channelways of the ore-forming solutions, taking place under conditions of definite dif-ference between metal concentrations, in solutions and wallrocks, followed by differential deposition, consti-tute possible dynamic mechanisms for the primary metal zoning.

关键词： Met rate The Dynamic Mechanisms for the Formation of Primary Metal Zoning of Cassiterite-Sulfide Deposits in the Gejiu Metallogenic Province Yunnan

The Depositional Environment of the Cretaceous Kizilsu Group in Xinjiang——With a Discussion of the Lowermost Marine Horizon of the Cretaceous in the Western Tarim Basin

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Acta Geologica Sinica(English Edition) 1991年第4期65卷 441-453页

作者： Guo Xianpu china university of geosciences, Beijing Sun Sheping china university of geosciences Beijing

In this paper. it is demonstrated that there exist marine horizons in the upper part of the lower subcycleand the upper subeycle of the Kizilsu Group in Xinjiang. based on new evidence of authigenic glauconite.boron content. carbon and oxygen stablc isotopic analyses. and lithological and sedimentary features. The up-per part of the lower subeycle is the lowermost marine horizon of the Cretaceous in the western Tarim Basin,which is inferred to be of Barremian age.

关键词： In With a Discussion of the Lowermost Marine Horizon of the Cretaceous in the Western Tarim Basin The Depositional Environment of the Cretaceous Kizilsu Group in Xinjiang

A Technique for Carbon and Chlorine Isotope Analyses of Chlorinated Aliphatic Hydrocarbons in Groundwater

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Journal of Earth Science 2013年第2期24卷 274-281页

作者：甘义群余婷婷周爱国刘运德刘存富 School of Environmental Studies China University of Geosciences State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences

Chlorinated aliphatic hydrocarbons （CAHs）, significant contaminants in groundwater, can be characterized by stable isotopic compositions of carbon and chlorine. Previously published methods were of low analytical sensitivity or not ideal for natural samples with low concentrations of CAHs. This method is reported here to carry out simultaneously carbon and chlorine isotope analyses for mieromolar concentrations of dissolved CAHs. It was executed by extracting and converting CAHs to carbon dioxide and methyl chloride （CH3CI）. Specially, a continuous-flow interface GasBench Ⅱ was used to extract CH3CI for online chlorine isotope analysis. As a result, it greatly enhances the efficiency for isotope analysis by eliminating procedures for offline CH3CI preparation and separation. Sample size requirement was reduced to approximately 11 pmol chlorine. The standard deviation of δ^＋3C and δ^37CI for both TCE solvents and water samples was better than 0.30‰ and 0.20%0 （1σ）, *** and chlorine isotope analyses can be used as an important tool to study the sources of organic contaminants in groundwater and their behaviors in the aquifers. The method is applicable to manufacturers＇ products as well as a sample from a polluted site in principle, which will be validated in our field studies.

关键词： chlorine isotope carbon isotope chlorinated aliphatic hydrocarbon (CAH) groundwater organic contamination.

Approach to the Relation of Mutual-Feed Joint-Variation in Groundwater Management Model

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Journal of Earth Science 2012年第3期23卷 349-358页

作者：李平卢文喜靳孟贵杨青春 College of Chemistry and Materials South-Central University for Nationalities School of Environmental Studies China University of Geosciences College of Environment and Resources Jilin University

In groundwater management,the exchanges between groundwater and other water such as surface water and spring water need to be *** exchange is dependent on the ground-water level,which is called *** pumping rate,groundwater level,and covariate interact and the relation of mutual-feed joint-variation is used to describe their *** article presents a new approach of dealing with the relation in groundwater management *** mathematical for-mulation of the relation,as an additional equality constraint in the optimization model,is developed using response matrix *** the groundwater management model with covariate is set *** code for the simulation and management of groundwater system with covariate is programmed with Fortran 90,and the optimal pumping rate,groundwater level,and covariate are *** approach is verified with a hypothetical ***,the approach is applied to the groundwater management of Qianguo（前郭） area in western Jilin（吉林） *** results indicate that the ap-proach is *** provides a universal solution for various covariates and reduces the computational complexity compared to iteration *** approach is proven to be very efficient to solve ground-water management problem with covariate.

关键词： covariate relation of mutual-feed joint-variation groundwater management response matrix

SHRIMP Zircon U-Pb Ages and Geochemical Characteristics of the Neoproterozoic Granitoids in the Huangling Anticline and Its Tectonic Setting

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Journal of Earth Science 2012年第5期23卷 659-675页

作者：魏运许彭松柏蒋幸福彭中勤彭练红李志宏周鹏曾雄伟 wuhan Institute of Geology and Minerals Resources Wuhan Center of Geological Survey Faculty of Earth Sciences China University of Geosciences Three Gorges Research Center for Geo-hazard Ministry of EducationChina University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences

SHRIMP zircon U-Pb dating of the Neoproterozoic Maoping （茅坪） series （Sandouping （三斗坪） rock suite） granites exposed in the southern part of the Huangling （黄陵） anticline shows that the formation time of Sandouping biotite-hornblende tonalite intrusion, Jinpansi （金盘寺） hornblende-biotite tonalite intrusion, and Longtanping （龙潭坪） monzogranite are 86.±9, 842±10, and 844±10 Ma, respectively. Their geochemical features include A/CNK=0.98-1.06. from metaluminous to weakly peraluminous, δ=1.37-1.53, Sm/Nd=0.17-0.24, and RbN/YbN=1.1-3.6.. These indicate that the granite rocks are supersaturated SiO2 calc-alkaline granitoids. The characteristic of Sr-Nd isotopic composition is that the values of εNd（t） and εsr（t） are -12.4 to -11.0 and 20.2-32.2, respectively. It also suggests that the material source of the granite rocks mainly originated from the crust, and they formed in a volcanic arc tectonic environment. These facts suggest that the occurrence of Neoproterozoic granitoids in the southern part of the Huangling anticline should be related to an arc environment along an active continental margin caused by southward subduction of oceanic crust beneath the northern Yangtze craton, and the formation age is not later than 86. Ma.

关键词： Huangling anticline Yangtze plate Neoproterozoic granitoid SHRIMP zircon U-Pbdating geochemistry tectonic setting.

The construction of Markov processes in random environments and the equivalence theorems

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Science china Mathematics 2004年第4期47卷 481-496页

作者： HU DiheSchool of Mathematics and Statistics, wuhan university, wuhan 430072, china School of Mathematics and Statistics Wuhan University Wuhan China

In sec.1, we introduce several basic concepts such as random transition function, p-m process and Markov process in random environment and give some examples to construct a random transition function from a non-homogeneous density function. In sec.2, we construct the Markov process in random enviromment and skew product Markov process by p - m process and investigate the properties of Markov process in random environment and the original process and environment process and skew product process. In sec. 3, we give several equivalence theorems on Markov process in random environment.

关键词： radom transition function, p -m process, Markov process in random environment, skew product Markov process, density function.

NEW WAVELET BASES FOR NON－HOMOGENEOUS SYMBOLIC SPACE OpS1,1^m AND RELATED KERNEL－DISTRIBUTION SPACES

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Chinese Annals of Mathematics,Series B 2002年第4期23卷 551-562页

作者： YANG QIXIANGDepartment of Mathematics, wuhan university, wuhan 430072, china. Department of Mathematics Wuhan University Wuhan 430072 China

This paper constructs several classes of new wavelet bases, which are unconditional bases for related operator spaces. Using these bases, the author analyzes non-homogeneous symbolic space OpSm1,1 and two related kernel-distribution spaces, and characterizes them in two wavelet coefficients spaces. Besides, some properties for singular integral operators are studied.

关键词： Wavelet bases Symbolic spaces Kernel-distribution spaces

Large deviation principles for stationary NA sequences

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Chinese Science Bulletin 1998年第7期43卷 536-540页

作者： HU Yijun Department of Mathematics, wuhan university, wuhan 430072, china Department of Mathematics Wuhan University Wuhan China

Under general conditions, the large deviation principles for partial sums of stationary NA sequences are proved.

关键词： NA sequence stationary sequence partial sums large deviation principle.

china stroke surveillance report 2021

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Military Medical Research 2024年第3期11卷 374-399页

作者： Wen-Jun Tu Long-De Wang 无 Department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China School of Public Health Peking UniversityBeijing 100191China Special Writing Group of china Stroke Surveillance Report

Since 2015,stroke has become the leading cause of death and disability in china,posing a significant threat to the health of its citizens as a major chronic non-communicable *** to the china Stroke High-risk Population Screening and Intervention Program,an estimated 17.8 million[95%confidence interval(CI)17.6.18.0million]adults in china had experienced a stroke in 2020,with 3.4 million(95%CI 3.3–3.5 million)experiencing their first-ever stroke and another 2.3 million(95%CI 2.2–2.4 million)dying as a ***,approximately 12.5%(95%CI 12.4%–12.5%)of stroke survivors were left disabled,as defined by a modified Rankin Scale score greater than 1,equating to 2.2 million(95%CI 2.1–2.2 million)stroke-related disabilities in *** the population ages and the prevalence of risk factors like diabetes,hypertension,and hyperlipidemia continues to rise and remains poorly controlled,the burden of stroke in china is also increasing.A large national epidemiological survey initiated by the china Hypertension League in 2017 showed that the prevalence of hypertension was 24.7%;the awareness,treatment,and control rates in hypertensive patients were:6..1%,42.5%,and 25.4%,respectively.A nationally representative sample of the Chinese mainland population showed that the weighted prevalence of total diabetes diagnosed by the American Diabetes Association criteria was 12.8%,suggesting there are 120 million adults with diabetes in china,and the awareness,treatment,and control rates in diabetic patients were:43.3%,49.0%,and 49.4%,***“Sixth National Health Service Statistical Survey Report in 2018”showed that the proportion of the obese population in china was 37.4%,an increase of 7.2 points from *** from 1599 hospitals in the Hospital Quality Monitoring System and Bigdata Observatory Platform for Stroke of china(BOSC)showed that a total of 3,418,432 stroke cases[mean age±standard error(SE)was(6..700±0.006.years,and 59.1%were male]were admitted dur

关键词： Stroke Epidemiological characteristics Treatment Prognosis china