管线网行业GIS应用系统快速开发研究     

殷丽丽  许婷  张书亮 《测绘工程》2006,15(1):50-53

针对管线网行业GIS应用系统的开发作了研究,分析了快速开发的依据,重点阐述基于可复用构件的软件开发方法和管线网行业领域模型的支持。论述了GIS应用系统在工程领域快速开发的体系结构、数据和操作的集成。实践表明,这种开发模式在GIS工程和应用领域提高了系统的开发效率和质量。  相似文献   

电感耦合等离子体原子发射光谱法测定掺锡氧化铟粉中的铁、铝、铅、镍、铜、镉、铬和铊量     

黄誓成  陆映东  聂小明  韦莉  黄肇敏  林葵  黎颖  韦猛 《矿产与地质》2019,(2)

掺锡氧化铟粉样品经氢氧化钠熔融,热水浸出盐酸酸化后,用电感耦合等离子体原子发射光谱仪直接测定试料溶液中待测元素特征谱线的强度,通过标准曲线法计算出试料中铁、铝、铅、镍、铜、镉、铬和铊量。方法检出限为0.0023～0.0075μg/mL,精密度(RSD值)为1.56%～11.15%,加标回收率在95.0%～112.1%之间。方法准确可靠,已被推荐为有色金属行业标准。  相似文献   

勐糯铅锌矿区断裂三角矿体的探采方法研究     

杨世成  吕品翰  王家仁 《云南地质》2019,(2)

云南龙陵县勐糯铅锌矿为一构造控制热液型矿床,矿体受断裂构造影响较大。在经过几十年的传统方法开采后,常常在断层附近遗留下一部分无法开采的、在空间上形态似三角形的矿体,本文通过对断裂三角矿体的成因分析,提出了一套针对性的探采结合新方法,经过重新布置探矿、采矿工程,使矿山开采的矿石损失率降低、资源利用率提高,经济效益增长,同时也为同类型矿山资源开采提供了一定的参考。  相似文献   

粒径比和配比对橡胶砂力学性能的影响研究     

刘方成  吴孟桃  王海东 《工程地质学报》2019,27(2):376-389

橡胶砂作为一种新型的廉价隔震材料具有广泛的应用前景,其力学变形特性受两种母材的配合比、粒径比等影响较大。为促进橡胶砂的工程应用,对3种粒径比、6种配比橡胶砂进行了一系列双轴压缩离散元模拟试验,从宏细观角度研究了胶-砂粒径比对橡胶砂力学行为的影响。结果表明:（1）橡胶砂应力-应变曲线在小应变下表现为近似线性增长关系,随着橡胶含量的增加,偏应力逐渐减小,减小程度随粒径比的增大而减弱;（2）随着橡胶颗粒含量的增加,橡胶砂模量降低、应力-应变曲线向硬化型转变、线性关系增强,粒径比越大,硬化特性越明显;（3）随着橡胶颗粒含量的增加,橡胶砂剪胀特性减弱、剪缩增大,粒径比越大,剪缩程度越明显;（4）橡胶砂应力-应变关系可用扩展邓肯-张模型进行模拟,模型参数受粒径比和橡胶颗粒含量影响的规律明显;（5）橡胶砂力学特性受粒径比影响的细观机制可由颗粒接触特性、颗粒配位数、力链分布、能耗发展等变化情况来描述。  相似文献   

衢州市上方镇方解石矿床碳、氧同位素地球化学特征     

刘成东  刘友  万建军  谭双  赵严  张辉  梁良  肖俊  张书嘉 《矿物岩石地球化学通报》2019,(2):374-378,394

为研究浙江省衢州市上方镇方解石矿床的成岩成矿环境,采集了上方镇方解石矿床中的大理岩样品,用MAT-253型气体同位素质谱仪对其进行了碳、氧同位素分析测试。结果表明,样品的δ¹³C_PDB和δ¹⁸O_SMOW均值分别为-1.32‰和18.25‰,计算的盐度指数Z值为97.42～130.08,均值为118.50,在δ¹⁸O_SMOW-δ¹³C_PDB图解上大多数样品点落于海相碳酸盐与碳酸盐溶解作用范围内,上方镇方解石矿床大理岩的原岩应为沉积成因,可能形成于宽阔的海洋环境。  相似文献   

深部地球条件下铁和氧元素的化学变化     

夏群科  Liu J  Hu Q Y  Bi W L  Yang L X  Xiao Y M  Chow P  Meng Y.Prakapenka V B  Mao H K  Mao W L 《矿物岩石地球化学通报》2019,(3):571-571

氧与铁分别为地球上丰度最高的元素与占地球质量最大的元素,它们所形成的化合物遍布我们的星球,具有-2价的氧控制着地球的氧逸度,随着深度的增加氧逸度逐渐降低,与铁所形成的氧化物中铁的价态也逐渐降低,O/Fe逐渐增加,近些年来科学家们发现深部地球条件下铁的一系列氧化物,其中具有高压黄铁矿结构的铁超氧化物FeO2具有最高的O/Fe,并且它还能够携带一定量的H(表示为Py-FeO2H,, x=0-1)。  相似文献   

Extensional collapse of the Gondwana orogen: Evidence from Cambrian mafic magmatism in the Trivandrum Block,southern India     

Qiong-Yan Yang  Sohini Ganguly  E.Shaji  Yunpeng Dong  V.Nanda-Kumar 《地学前缘(英文版)》2019,10(1):263-284

The assembly of Late Neoproterozoice Cambrian supercontinent Gondwana involved prolonged subduction and accretion generating arc magmatic and accretionary complexes, culminating in collision and formation of high grade metamorphic orogens. Here we report evidence for mafic magmatism associated with post-collisional extension from a suite of gabbroic rocks in the Trivandrum Block of southern Indian Gondwana fragment. Our petrological and geochemical data on these gabbroic suite show that they are analogous to high Fe tholeiitic basalts with evolution of the parental melts dominantly controlled by fractional crystallization. They display enrichment of LILE and LREE and depletion of HFSE with negative anomalies at Zre Hf and Ti corresponding to subduction zone magmatic regime. The tectonic affinity of the gabbros coupled with their geochemical features endorse a heterogeneous mantle source with collective melt contributions from sub-slab asthenospheric mantle upwelling through slab break-off and arc-related metasomatized mantle wedge, with magma emplacement in subduction to post-collisional intraplate settings. The high Nb contents and positive Nbe Ta anomalies of the rocks are attributed to inflow of asthenospheric melts containing ancient recycled subducted slab components and/or fusion of subducted slab materials owing to upwelling of hot asthenosphere. Zircon grains from the gabbros show magmatic crystallization texture with low U and Pb content. The LA-ICPMS analyses show ²⁰⁶ Pb/²³⁸ U mean ages in the range of 507-494 Ma suggesting Cambrian mafic magmatism. The post-collisional mafic magmatism identified in our study provides new insights into mantle dynamics during the waning stage of the birth of a supercontinent.  相似文献   

Timescales of interface-coupled dissolution-precipitation reactions on carbonates     

Fran?ois Renard  Anja R?yne  Christine V.Putnis 《地学前缘(英文版)》2019,10(1):17-27

In the Earth's upper crust, where aqueous fluids can circulate freely, most mineral transformations are controlled by the coupling between the dissolution of a mineral that releases chemical species into the fluid and precipitation of new minerals that contain some of the released species in their crystal structure, the coupled process being driven by a reduction of the total free-energy of the system. Such coupled dissolution-precipitation processes occur at the fluid-mineral interface where the chemical gradients are highest and heterogeneous nucleation can be promoted, therefore controlling the growth kinetics of the new minerals. Time-lapse nanoscale imaging using Atomic Force Microscopy (AFM) can monitor the whole coupled process under in situ conditions and allow identifying the time scales involved and the controlling parameters. We have performed a series of experiments on carbonate minerals (calcite, siderite, dolomite and magnesite) where dissolution of the carbonate and precipitation of a new mineral was imaged and followed through time. In the presence of various species in the reacting fluid (e. g. antimony, selenium, arsenic, phosphate), the calcium released during calcite dissolution binds with these species to form new minerals that sequester these hazardous species in the form of a stable solid phase. For siderite, the coupling involves the release of Fe²⁺ ions that subsequently become oxidized and then precipitate in the form of Fe^III oxyhydroxides. For dolomite and magnesite, dissolution in the presence of pure water (undersaturated with any possible phase) results in the immediate precipitation of hydrated Mg-carbonate phases. In all these systems, dissolution and precipitation are coupled and occur directly in a boundary layer at the carbonate surface. Scaling arguments demonstrate that the thickness of this boundary layer is controlled by the rate of carbonate dissolution, the equilibrium concentration of the precipitates and the kinetics of diffusion of species in a boundary layer. From these parameters a characteristic time scale and a characteristic length scale of the boundary layer can be derived. This boundary layer grows with time and never reaches a steady state thickness as long as dissolution of the carbonate is faster than precipitation of the new mineral. At ambient temperature, the surface reactions of these dissolving carbonates occur on time-scales of the order of seconds to minutes, indicating the rapid surface rearrangement of carbonates in the presence of aqueous fluids. As a consequence, many carbonate-fluid reactions in low temperature environments are controlled by local thermodynamic equilibria rather than by the global equilibrium in the whole system.  相似文献   

EVALUATION OF TOPOGRAPHIC INDICES FOR EPHEMERAL-GULLY EROSION ASSESSMENT     

J. CASALI L. M. De SANTISTEBAN J. J. LOPEZ J. V. GIRALDEZ J. POESEN J. NACHTERGAELE M. GONI J. LOIZU M. A. CAMPO 《国际泥沙研究》2005,20(4):295-304

1 INTRODUCTION Erosion caused by ephemeral flows is a frequent phenomenon in nature and contributes to the shape of the landscape. This type of erosion may cause great soil losses in agricultural areas, which are quickly transferred to the watershed outlets through the rill and gully network (Bennett et al., 2000; Poesen et al., 2003). Concentrated flow erosion is controlled by the erodibility of surface materials, climate, soil use and management, and watershed topography. Several metho…  相似文献   

加强"误差理论与测量平差基础"课程教学的探讨   总被引：11，自引：1，他引：10  

张书毕 《测绘通报》2004,(5):56-57

在对测量平差教学调查分析的基础上．提出测量平差优秀教材建设、教学方法的改革、师资和研究队伍建设是加强“误差理论与测量平差基础”课程教学的根本保证。  相似文献