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101.
CORS在线定位用户服务系统 总被引:2,自引:0,他引:2
首先对基于CORS的在线定位用户服务系统功能进行了较细致的分析,将其概括为7项基本功能和4项扩展功能。在此基础上提出了系统架构方案,将系统划分为3个部件和20个子部件,并对各组成部分的功能作了较详细的阐述。最后,针对用户数据上传与存储、基线解算和基线向量网平差等核心功能,提出了较具体的设计方案,并对软件实现与系统集成方法进行了阐述。 相似文献
102.
本文首先介绍了南京市首级高程控制网的概况,接着重点讨论了跨江水准测量方法的选择,并全面分析了测距三角高程法影响精度的三个因素,结合南京市首级高程控制网全面介绍了数据处理的有关问题。 相似文献
103.
通过对胶东牟平—乳山热液脉状金,铅锌矿床成矿动力学控制规律的研究,说明了建立热液成矿反应体系的方法,并得出以下认识:(1)区域断裂构造活动,通过影响成矿反应体系的热力学性质和条件,控制元素的富集和分散。(2)热液成矿过程中容矿断裂活动可划分为两种作用方式:脆性破裂和韧—脆性张开,构成热液成矿的两种构造动力学环境。(3)热液成矿反应体系是一种开放的动态的热力学体系。断裂的脆性破裂阶段,使体系处于强烈的过饱和状态,矿质在远离平衡状态下快速结晶,加剧物质分异;在脆—韧性张开阶段,矿质在接近平衡态体系中缓慢晶出。(4)热液演化晚期,金在残余溶液中富集;当断裂再次发生构造脉动震颤时,早期形成的块状黄铁矿矿石碎裂,富金溶液充填其中,形成含裂隙金和晶隙金的富矿石。成矿体系热力学演化与构造动力学条件有利的匹配控制着富矿石的形成。 相似文献
104.
新疆第四纪盐类矿产的形成和控制因素——兼论“高山深盆”成盐模式 总被引:1,自引:0,他引:1
根据袁见齐教授“高山深盆”成盐模式,探讨新疆天山对第四纪盐类矿床的形成和控制作用,阐述了天山地貌、气候、水文特征与盐类矿产的分布规律和特征。认为“高山深盆”并非一定是四周环山的深盆,可以是某一高山与其间深盆或两侧盆地的有机组合。高山的屏障作用造成了垂直的气候分带,在潮湿多雨的山区利于成盐组份的析出并迁移到干旱少雨的闭流深盆中,形成盐类矿床。 相似文献
105.
为了合理地求定按附合网平差的网点坐标的实际精度,本文推广了半动态法,籍此可在首级网的基准下,统一求定顾及各级控制网测量误差影响精度的全部网点坐标的方差—协方差阵。本文所提出的方法适用于种种情况下的精度估计:等级数不受限制的平面、高程或三维网,本级网平差中的固定数据以及待估计的平差值函数可以包含不同级的网点,从而克服了半动态法原有的局限性。 相似文献
106.
Savitri Tripathi Vandana Parth Phani Homeshwari M. Vittal Babu N. Murthy N.N. Sorlie J.E. Govil P.K. 《中国地球化学学报》2006,25(B08):117-118
Permeable Reactive Barrier (PRB) is an emplacement of inert material (s) in the subsurface, designed to intercept a contaminated plume, provides a preferential flow path through the reactive media, and transforms the contaminant into environmentally acceptable forms to attain concentration remediation goals at the discharge of the barrier. The phenomena, which help in remediation within PRB, are adsorption/sorption, precipitation, oxidation/reduction and biodegradation. Various materials like zero-valent iron, zero-valent bi-metals, natural zeolites, organic carbon, fly ash, zeolites, limestone, activated alumina, apatites, etc. have been tried by many researchers to remove organic and inorganic contaminants. In USA, Canada, and many European countries commercial full-scale and pilot scale PRBs are successfully working. The design and installation of full scale PRBs needs laboratory treatability and dynamic flow column experiments? The concept of PRB is being applied to treat contaminated surface water in the Katedan industrial area, Hyderabad, India. National Geophysical Research Institute (NGRI), Hyderabad, India, conducted systematic studies in collaboration with Norwegian Geotechnical Institute (NGI), Norway, to develop PRB technique to decontaminate the surface water pollution due to industrial effluent. A site assessment study in the Katedan Industrial Area, were carried out and water, soil and sediment from the lakes of the area were found to be polluted with high concentrations of heavy metals like As, Pb, Cr, Cd, Ni, etc. Adsorption studies at NGRI with synthetic samples and in-situ industrial effluent using different reactive media for removing contaminants like arsenic, chromium, cadmium, copper, nickel, lead and zinc have been carried out and yielded satisfactory results. The performance of zero-valent iron and limestone is encouraging in removing As, 相似文献
107.
Marvin Joseph Montefrio Kai Scene Ng Lee Yih Koh Erwin Torio Mark Hansley Chua Louernie de Sales-Papa Jeffrey Philip Obbard 《中国地球化学学报》2006,25(B08):122-122
The gross environmental condition of the Payatas Disposal Facility in Metro Manila, Philippines, implores the need for sustainable technologies to control and abate toxic municipal solid waste leachate and protect public health. A team of environmental engineers recognized this need by selecting the site as a design project for the Mondialogo Worldwide Engineering Award, sponsored by the United Nations and Daimler Chrysler. The project culminated in a technical proposal that highlighted the following design features: an impermeable dumpsite cap to control leachate generation; vertical impermeable barriers for containment and isolation of leachate; a drainage system to divert clean, surface water from the cap and prevent its contamination prior to discharge; a leachate recirculation system to enhance stabilisation of the waste deposit; and a facultative lagoon and constructed wetland system to treat excess leachate. 相似文献
108.
Yoshio Takahashi Yutaka Kanai Hikari Kamioka Atsuyuki Ohta Takuro Miyoshi Hiroshi Shimizu 《中国地球化学学报》2006,25(B08):222-222
Sulfates are a main constituent of aerosols, which sulfate aerosols, it is necessary to determine what can cause various environmental problems sulfate ions are contained in these aerosols In the evaluation of the influence of In this study, sulfur K-edge XANES was used to determine sulfate species present in size-fractionated aerosol particles based on the post-edge structure after the main absorption peak in the XANES region. Aerosol samples were collected as part of the Japan-China joint project, "Asian Dust Experiment on Climate Impact" using a low-volume Andersen-type air sampler. XANES was measured at Beamline BL-9A at Photon Factory, Japan. A comparison of the XANES spectra of reference sulfate materials and aerosol samples collected in Tsukuba in Japan clearly showed that (NH4)2SO4 was the main sulfur species in particles with a smaller diameter and gypsum was the main sulfur species in particles with a larger diameter. A simulation of the XANES spectra by reference materials allows us to obtain the quantitative mixing ratios of the different sulfate species present in the aerosol samples. The presence of minor sulfur species other than (NH4)2SO4 and gypsum at the surface of mineral aerosols is suggested in our simulations and by a surface-sensitive conversion electron/He-ion yield XANES. In the absence of a contribution from a large dust event, the mole concentration of gypsum in the mineral aerosol fraction determined by XANES is similar to that of Ca which is determined independently using ion chromatography. This shows that the Ca and sulfate in the mineral aerosols are present only as gypsum. Considering that calcite is the main Ca mineral in the original material arising from an arid and semi-arid area in China, it is strongly suggested that gypsum is formed in aerosol during its long-range transportation by a reaction between calcite and sulfate ions. 相似文献
109.
周贤旭 《华东地质学院学报》2006,(Z1)
通过对香炉山地区成矿控制因素分析,认为香炉山特大型钨矿外围具备找大矿的条件,并依据成矿控制主要因素在找矿远景区的具体体现,提出了在徐家岭、张天罗、大岩下等多处具有较好的找矿远景区。对张天罗、徐家岭及大岩下等较重要的找矿前景区进行详细叙述。 相似文献
110.
探讨了中小城市首级GPS控制网的几种布测方案,用实测GPS数据对几种常用的布测方案进行了精度分析,从而确定城市首级GPS控制网的最佳布设方案。 相似文献