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1.
针对中国新生代第三系广泛分布的咸化湖相盆地的成因及地球化学环境意义,比较系统地分析了中国新生界咸化湖相地层生油岩及原油中饱和烃、芳香烃等化合物的地球化学特征。分析结果表明:咸化湖地层中有机质的地球化学(生物标志物组合)特征,既不同于淡水湖相地质中的有机质,又与海相地层中的有机质存在明显的差别。进一步讨论了造成这一现象的地球化学成因及其环境地球化学意义,并对其中部分生物标志物及稳定碳同位素组成特征的指相意义作了探讨。通过生物标志物的组合特征和环境地球化学意义分析,初步认为中国新生代第三系咸化湖盆咸化湖泊的形成与海浸作用没有直接的联系。  相似文献   

2.
本文介绍了工程地质环境中地球化学作用的多样性及其机理,讨论了利用人工地球化学方法增强岩(土)体强度和降低岩(土)体渗透性的可行性,认为工程地球化学在保护工程地质环境稳定性等方面前景广阔。  相似文献   

3.
俯冲带环境下物质运移机理研究是当前板块构造理论研究的前沿和热点。本文从俯冲带火山岩的地球化学组成特征、俯冲带构造环境下变质岩的的地球化学组成特征和高温高压实验三个方面,探讨了俯冲带环境下物质运移的研究方法的理论。  相似文献   

4.
邱贵川 《遵义科技》2006,34(3):31-32
本文介绍了工程地质环境中地球化学作用的多样性及其机理,讨论了利用人工地球化学方法增强岩(土)体强度和降低岩(土)体渗透性的可行性,认为工程地球化学在保护工程地质环境稳定性等方面前景广阔。  相似文献   

5.
珠江三角洲地区地方病主要有地氟病、地甲病和肝癌、鼻咽癌。地甲病和地氟病的主要病因可能分别是氟、碘元素。对与氟、碘元素产生颉颃作用、协同作用的元素的研究是进一步厘定地氟病、地甲病与地球化学环境关系的重要方面。作为流行病的肝癌和鼻咽癌的病因尚未探明,需要在前人研究的基础上,开展环境地球化学、医学地质学和多元统计分析等多学科方法的综合研究。  相似文献   

6.
地球化学新书《地球的化学过程与物质演化》由中国地球化学学会组织编写。欧阳自远院士在前言中说,希望通过对地球化学发展历程的百年回眸,从地球化学是研究地球的化学过程与物质循环这个总体思路出发来介绍地球化学学科的研究对象、研究内容和在科技发展中的地位、作用;传播地球化学的科学知识与科学思想、科学方法的形成、发展与应用;并力图使科学性、知  相似文献   

7.
陈永亨,1954年11月出生,教授,博士生导师,享受国务院颁发的政府特殊津贴。1990年毕业于中国科学院地球化学研究所,获理学博士学位。现任广州大学环境科学研究所所长,中国科学院广州廿乜球化学研究所有机地球化学国家重点实验室、中国科学院地球化学研究所环境地球化学国家重点实验室客座研究员。陈永亨教授1987~1990年期间在德国马普核物理研究所工作和学习,  相似文献   

8.
近年来,地球化学方法不断地用于地下水的勘探,环境同位素技术也被当作地球化学方法的一部分。最常用的环境稳定同位素氚和~(18)O作为水的理想示踪剂比地球化学示踪剂具有更明  相似文献   

9.
生态环境恶化,使人类面临生存和发展危机。本文以地区环境为例,试图讨论景观地球化学在环境工作中的应用。它从人类活动与环境质量变化的关系出发,运用地球化学方法,研究环境中的地球化学景观系列,进行景观地球化学区划,揭示环境质量变化的规律,为环境质量评价、环境保护和环境治理提供科学依据  相似文献   

10.
2004年6月5-11日,在丹麦首都哥本哈根召开了第14届戈尔德斯密特(Goldschmidt)国际地球化学会议,共有46个国家和地区的约l500名参会代表。会议议题主要包括宇宙化学、地球化学和环境地球化学,主要涉及固体动力学、界面动力学、地球挥发份、地球表面、地球深部及早期地球和行星的地球化学过程6个专题。会议重点交流的内容主要集中在地球的层圈及其相互作用、环境和气候的地球化学示踪等方面,  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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