客户机/服务器结构的地图数据库分布管理     

吴金华  李芹芳 《地球科学与环境学报》2001,23(3):68-70

叙述了客户机/服务器结构的地图数据库发展的必要性,对客户机/服务器结构的地图数据库分布管理概念、结构及网络环境进行了论述和设计.  相似文献   

⁴⁰Ar/³⁹ mineral ages from the Scituate Granite, Rhode Island: implications for Late Palaeozoic tectonothermal activity in New England     

R. D. DALLMEYER  O. D. HERMES  J. I. GIL-IBARGUCHI 《Journal of Metamorphic Geology》1990,8(2):145-157

The alkalic Scituate Granite was emplaced into crystalline sequences within the New England Esmond–Dedham terrane in the Late Devonian ( c. 370 Ma). Variably recrystallized amphibole (iron-rich, hastingsite–hastingsitic hornblende) from four variably deformed samples of the pluton record south-westerly younging ⁴⁰Ar/³⁹Ar plateau ages ranging between 276 and 263 Ma. These are interpreted to date diachronous cooling through temperatures appropriate for intracrystalline retention of argon following late Palaeozoic orogenic activity. Iron-rich biotite concentrates from the samples record only slightly younger ages, and therefore suggest relatively rapid post-metamorphic cooling. The ⁴⁰Ar/³⁹Ar ages indicate that the late Palaeozoic tectonothermal overprint was much more regionally pervasive than was previously considered. The apparent timing of this activity is similar to previous estimates for the chronology of high-grade metamorphism throughout the adjacent Hope Valley terrane and for phases of ductile movement on the intervening Lake Char–Honey Hill fault system.  相似文献   

Bistable profile illumination in pulsars B0919+06 and B1859+07     

Joanna M. Rankin  Cameron Rodriguez  Geoffrey A. E. Wright 《Monthly notices of the Royal Astronomical Society》2006,370(2):673-680

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Sol－gel法制取Al_2O_3系陶瓷涂层的组织与性能     

魏续占 《地球科学与环境学报》1996,(2)

用多种分析手段分析了Ｓｏｌ－ｇｅｌ法制取的Ａｌ２Ｏ３系陶瓷涂层在烧结过程中的组织变化以及烧结后涂层的成分和组织结构；对涂层的高温抗氧化性、耐蚀性、耐磨性以及涂层与金属基体的结合力进行了测试，结果表明，Ｓｏｌ－ｇｅｌ法制取的Ａｌ２Ｏ３系陶瓷涂层由氧化物晶体、过渡相和玻璃体混合而成，涂层与基体之间有很好的结合力，金属基体的抗氧性、耐蚀性、耐磨性能有明显提高．  相似文献   

Evidence for Chemical Heterogeneity in the Nucleus of C/1995 O1 (Hale–Bopp)     

Lederer  Susan M.  Campins  Humberto 《Earth, Moon, and Planets》2002,90(1-4):381-389

We present an analysis of OH, CN, and C₂ jets observed in thecoma of Comet Hale–Bopp on UT April 22, 23, and 25, 1997. Monte Carlomodels designed to simulate the gas jets were employed to analyze thenuclear active areas responsible for the observed coma gas jets. Ourresults indicate that four active areas are necessary to reproduce theCN and C₂ jets while five active areas are required to simulatethe OH jets. The additional OH active area must produce significantlevels of OH, but cannot emit measurable quantities of either carbonradical. This difference suggests that the nucleus of Comet Hale–Boppis chemically heterogeneous.  相似文献   

Comet Hale–Bopp: Velocity Field Of Ions From Fabry-Pérot Imaging     

Bonev  T.  Jockers  K.  Credner  T. 《Earth, Moon, and Planets》1997,77(3):245-252

Fabry-Pérot interferograms of comet Hale-Bopp were obtained on several nights in March and April 1997. For this purpose we utilized the 2-channel focal reducer of the Max-Planck-Institute for Aeronomy at the 2-m telescope of the Pik Terskol Observatory. Solid Fabry-Pérot etalons of resolving power 30000 were used in both channels of the focal reducer. The main aim of this study is to measure the velocities and abundances of OH⁺ and H₂O⁺, both ions closely related to the same parent molecule, H₂O. In the blue channel interferograms we identified several individual OH⁺ rotational lines of the A³Π_i - X³Σ⁻ (0-0) transition and measured their Doppler shifts. The target emissions in the red channel were the H₂O⁺ lines of the A²A₁ − X²B₁ (10-0) band. We found that the line of sight velocities, obtained from the Doppler shifted wavelengths of emissions in the comet are higher in sunward direction than in the plasma tail and do not exceed 20 km s^–1. The corresponding values, deprojected in antisolar direction, are consistent with predictions by magnetohydrodynamical models of the solar-wind-comet interaction, when one accounts for the extremely high gas production rate of comet Hale-Bopp. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Changes in the Chemical Components of Light Crude Off During Simulated Short Term Weathering     

MA Qimin LUO Xia YU Zhigang 《中国海洋大学学报(英文版)》2007,6(3):231-236

To unambiguously identify spilled oils and to link them to the known sources are extremely important in settling questions of environmental impact and legal liability. The fate and behavior of spilled oils in the environment depend on a number of physicochemical and biological factors. This paper presents the results regarding changes in chemical composition of light crude oil during simulated short-term weathering based on natural environmental conditions. The results show that the saturated hydrocarbons of the light crude oil mainly distribute between n-C8 and n-C23 and the most abundant n-alkanes are found in the n-C10 to n-C16. The main chemical components of the light crude oil are n-alkanes and isoprenoids. The aromatic compounds are subordinate chemical components. Under the conditions of the weathering simulation experiment,n-alkanes less than n-C12,toluene and 1,3-dimethyl benzene are lost after 1 d weathering,the n-C13,n-C14,naphthalene and 2-methyl-naphthalene are lost on the fifth day of weathering,and n-C15 alkane components show certain weatherproof capability. The ratios n-C17/pristane and n-C18/phytane are unaltered and can be used to identify the source of the light crude oil during the first 8 d of weathering. After 21 d,the ratio pristine/phytane can not provide much information on the source of the spilled light crude oil. Triterpanes（m/z 191） as biomarker compounds of light crude oil are more valuable.  相似文献   

中亚造山带中的燃烧变质事件及其年代学研究   总被引：2，自引：1，他引：1  

Igor S. Novikov Ellina V. Sokol 《岩石学报》2007,23(7):1561-1572

Combustion metamorphic(pyrometamorphic)complexes produced by prehistoric natural coal fires are widespread inCentral Asia,namely at the interfaces between mountain systems and the flanking sedimentary basins.Large-scale and prolonged firesaccompanied the initial orogenic stages as unweathered coal-bearing formations became exposed into the aeration zone.Pyrometamorphic rocks are comparable to sanidinite facies rocks in formation conditions and in alteration of sedimentary material but,unlike these,their protolith underwent different melting degrees to produce either ferrous basic paralavas or glazed clinkers.The phasecomposition of the newly-formed melted rocks are favorable for~(40)Ar/~(39)Ar dating of combustion metamorphic events which are coeval tothe onset of the main stage of recent orogenic events.We suggest a new algorithm providing correct ~(40)Ar/~(39)Ar dating ofpyrometamorphic rocks followed by well-grounded geological interpretation.We studied pyrometamorphic rocks in the western Salairzone of the Kuznetsk coal basin where combustion metamorphism under temperatures above 1000℃acted upon large volumes of coal-bearing sediments.Samples of paralavas were dated by the step heating ~(40)Ar/~(39)Ar method checked against internal(plateau andisochrone ages)and external("criterions of couple")mineralogical criterions,and against preliminary dating from geological andstratigraphic evidence.As a result,we distinguished two groups of dates for combustion metamorphic events.The first one(1.2±0.4Ma)is drawn towards the west boundary of Prokopyevsk-Kiselevsk block of Salair zone,while the second one(0.2±0.3Ma)isconfined to its east boundary.The former ages represent rocks in the western edge of the Prokopievsk-Kiselevsk block of the Salair zoneand the latter ages correspond to those in its eastern edge.The dates record the time when the fault boundaries of the blocks wererejuvenated during recent activity and the block accreted to the Salair orogenic area as a piedmont step.These are the first absolute agesobtained for the onset of uplift of the northern edge of the Ahai-Sayan area,the key event of its neotectonic history.The suggestedapproach to the choice of objects,classification of rocks,and interpretation of~(40)Ar/~(39)Ar data is universal and can be practiced in anyarea subjected to combustion metamorphism.  相似文献   

地下侧积砂坝建筑结构研究及储层评价——以孤东油田七区西Ng52+3砂体为例   总被引：6，自引：0，他引：6  

李阳  郭长春 《沉积学报》2007,25(6):942-948

分析了在不同沉积环境下侧积砂坝的沉积模式,研究了侧积体的空间组合特征,并利用模式预测的方法建立侧积砂坝的建筑结构模型。研究表明,孤东油田七区西Ng52+3侧积砂坝是小型河流形成的,其侧积体的空间组合模式为水平斜列式,侧积体的宽度为80～240 m,倾角为5°～12°。薄片、扫描电镜分析证实,七区西Ng52+3的成岩作用较弱,原始的粒间孔隙保存完好,储层孔隙度平均为32.3%,渗透率为3 500×10-3 μm2。侧积砂坝内含有高岭石、蒙脱石、伊利石等粘土矿物,使其储层物性变差。  相似文献   

SAS/ETS在变形监测数据处理中的应用   总被引：3，自引：0，他引：3  

潘华志  耿则勋  夏治国  刘孝明 《测绘工程》2007,16(1):59-61,65

在综合考虑数学模型的预测精度与编程实现的可操作性基础上,提出了利用模块对变形监测数据进行时间序列分析,并概括介绍了该模块的3个主要命令使用方法,解决了时间序列分析在监测数据处理中实现起来非常繁琐的问题。最后通过与环境下动态灰色模型综合比较,证明了时间序列分析在变形监测数据处理中操作简单,模拟精度和预测精度都较高。  相似文献