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181.
熔融制样X射线荧光光谱法测定铜矿石中16种主次量元素   总被引:1,自引:1,他引:0  
铜矿石类型繁多,矿石赋存状态各异,成分复杂。在现有的铜矿石熔融制样X射线荧光光谱(XRF)分析方法中,选取标准物质个数和矿石类型少、分析范围宽,与实际样品类型相差太大,且制备的熔融片质量不高。本文选用铜含量既有良好浓度变化范围,又符合铜矿石常见含量的包括铜金银铅锌钼铜镍等各类矿石的24个标准物质,以四硼酸锂-偏硼酸锂-氟化锂为混合熔剂,熔剂与样品质量比为30:1,以溴化锂为脱模剂,改进样品预处理方式,将通常采用样品预氧化后或熔融中加入脱模剂的方式,改进为加入脱模剂后再用混合熔剂完全覆盖的方法制备了高质量的熔融片,建立了XRF测定铜矿石中铜锌铅硅铝铁钛锰钙钾镁钼铋锑钴镍16种元素的分析方法。分析铜矿石国家标准物质GBW 07164、GBW 07169,各元素的精密度(RSD)为0.1%~5.4%。分析国家标准物质GBW 07163(多金属矿石)、GBW 07170(铜矿石)的测定值与标准值相符;分析实际铜矿石样品,铜锌铅钼铋锑钴镍的测试结果与电感耦合等离子体发射光谱法和其他方法的测定值相符。本文方法扩大了基体的适应性,提高了实际应用价值。  相似文献   
182.
石菊松  曲永新  李滨  吴树仁 《地质通报》2013,32(12):1911-1917
陕西宝鸡市新近系硬粘土包括风成三趾马红土和“古三门湖河湖相堆积”的硬粘土,是西北地区典型的硬粘土地层之一,也是控制宝鸡市北坡黄土塬边大型滑坡分布的关键地层。为了深入认识该类特殊岩土,尤其是膨胀性粘土矿物(蒙脱石和其混层矿物),根据该类地层的空间分布特征采集了30多个岩土样品,在宏观与细观结构特征分析基础上,利用移液管法、精细X-射线衍射(XRD)技术、乙二醇与乙醚极性有机分子吸附法,完成了样品粒度成分的定量分析和粘土矿物的精细测定,分析其膨胀势,并结合区域滑坡分布与工程边坡病害,揭示其边坡灾害效应。  相似文献   
183.
This paper presents results from an experimental study performed on natural and compacted expansive soils in different loose and dense states using principally osmotic oedometers. The loose soils showed significant shrinkage, while the dense soils produced a swelling accumulation during the suction cycles. These cycles induced an equilibrium stage, which indicates an elastic behaviour of the samples under suction cycles. At the end of suction cycles, a loading/unloading test was performed on all samples at different constant suctions to define LC (loading collapse) yield curve as well as the newly defined SC (saturation curve) yield curve. Generally, the suction cycles for the looser soils approached the LC and SC yield curves while they became the same at the equilibrium state. For the denser soils producing the swelling strain accumulation, the unique LC and SC curves were activated together. Additionally, we found that at the equilibrium stage, both initially loose and dense samples presented the same mechanical parameters. In other words, the LC or SC yield curves superimposed for different initial states of the samples at the equilibrium stage. Moreover, these compression curves provided sufficient data to propose a simplified model for the mechanical behaviour of the swelling soils at the equilibrium stage.  相似文献   
184.
PS剂驱油矿场先导性试验研究   总被引:1,自引:1,他引:1  
PS碱木素磺酸盐 (简称 PS剂 )是由造纸废液经浓缩加入酚、醛和硫酸等在高温下复配或反应后提炼出的 1种新型表面活性剂。由于其具有降低原油粘度和油水界面张力的特性[1 -2 ] ,因而可作为提高原油采收率的驱替剂应用到油田开采中。本文通过室内实验和 W31断块的现场驱替试验 ,进一步探讨了 PS剂的驱替机理和驱油效果、探索了注 PS剂驱油的现场经验。  相似文献   
185.
Agent技术在分布式GIS中的应用研究   总被引:8,自引:0,他引:8  
首先分析了分布式计算技术的发展,详细介绍了当今主流的分布计算技术——Agent技术、分布式GIS技术是以分布式计算技术为依托的,Agent技术将为分布GIS带来新的技术发展;随后,深入分析了Agent技术在分布式GIS中的应用,并结合已有的研究重点介绍了基于Agent的分布式GIS建模、空间信息查找与获取、WebGIS服务体系、空间辅助决策以及GIS互操作等。  相似文献   
186.
This paper discusses the issues of positional accuracy and measurement error in the context of a large empirical study of landscape change in England and Wales. The epsilon band model of digitizing accuracy is used to make estimates of the levels of positional uncertainty and measurement error that is due to digitizing polygon outlines. The degree of error expected had the same polygons been captured in raster format is then determined. These results prompt a general discussion of the nature of error in spatial databases.  相似文献   
187.
We use a GIS‐based agent‐based model (ABM), named dynamic ecological exurban development (DEED), with spatial data in hypothetical scenarios to evaluate the individual and interacting effects of lot‐size zoning and municipal land‐acquisition strategies on possible forest‐cover outcomes in Scio Township, a municipality in Southeastern Michigan. Agent types, characteristics, behavioural methods, and landscape perceptions (i.e. landscape aesthetics) are empirically informed using survey data, spatial analyses, and a USDA methodology for mapping landscape aesthetic quality. Results from our scenario experiments computationally verified literature that show large lot‐size zoning policies lead to greater sprawl, and large lot‐size zoning policies can lead to increased forest cover, although we found this effect to be small relative to municipal land acquisition. The return on land acquisition for forest conservation was strongly affected by the location strategy used to select parcels for conservation. Furthermore, the location strategy for forest conservation land acquisition was more effective at increasing aggregate forest levels than the independent zoning policies, the quantity of area acquired for forest conservation, and any combination of the two. The results using an integrated GIS and ABM framework for evaluating land‐use development policies on forest cover provide additional insight into how these types of policies may act out over time and what aspects of the policies were more influential towards the goal of maximising forest cover.  相似文献   
188.
To improve the efficiency of planning and designing silt dam systems, this article employs theories and technologies of collaboration and distributed virtual geographic environments (VGEs) to construct a collaborative virtual geographic environment (CVGE) system. The CVGE system provides geographically distributed users with a shared virtual space and a collaborative platform to implement collaborative planning. Many difficulties have been found in integrating data resources and model procedures for the planning of silt dam systems because of their diversity in heterogeneous environments. Unlike most of the current distributed system applications, the proposed CVGE system not only supports multi-platform and multi-program-language interoperability in the dynamically changing network environment, but also shares programs, data and software in the collaborative environment. Based on creating a shared 3D space by virtual reality technology, agent and grid technologies were tightly coupled to develop the CVGE system. A grid-based multi-agent system service framework was designed to implement this new paradigm for the CVGE system, which efficiently integrates and shares geographically distributed resources as well as having the ability to build modelling procedures on different platforms. At the same time, mobile agent computing services were implemented to reduce the network load, process parallel tasks, enhance communication efficiency and adapt dynamically to the changing network environment. Using Java, JMF (Java Media Framework API), Globus Toolkits (GT) core, Voyager, C++, and the OpenGL development package, a prototype system was developed to support silt dam systems planning in the case study area, the Jiu-Yuan-Gou watershed of the Loess Plateau, China. Compared with the traditional workflow, the CVGE system can reduce the workload by between one third and a half.  相似文献   
189.
复杂地层钻探堵漏浆液的研究与应用   总被引:8,自引:0,他引:8  
王李昌 《地质与勘探》2013,49(4):770-776
在钻进复杂地层的过程中,漏失会造成冲洗液不同程度的流失,失去冲洗液的功能,导致钻进困难,钻速下降,以致孔壁坍塌发生卡钻、埋钻事故。此外,如遇到高气压层、水气,也可能发生喷气和涌水事故。为了确保安全钻进,必须采取一定的技术措施以防止冲洗液的漏失。泥浆是一种常规的护壁堵漏的措施,但对于坍塌漏失较严重的情况,就必须采用其它材料进行堵漏。本试验采用复合水泥浆液进行堵漏,对浆液中加入的处理剂与浆液性能改变之间的关系进行分析总结,主要对浆液的凝结时间、流动度、析水率等方面进行研究,再进行多组试验得出用以解决复杂地层堵漏的浆液优化配方。  相似文献   
190.
南水北调潞王坟段弱膨胀土膨胀性研究   总被引:1,自引:0,他引:1  
项伟  董晓娟 《岩土力学》2012,33(4):986-992
河南新乡潞王坟段膨胀土系第三系泥灰岩风化而成,以高岭石黏土矿物为主,具有弱膨胀性,其膨胀变形特性受孔隙结构影响比较大。为了清楚地研究试验段弱膨胀土的膨胀特性,从有荷膨胀变形、膨胀应力、循环胀缩变形3个方面进行研究,得出不同于以往其他膨胀土的膨胀变形特性:(1)当初始干密度比较小时,上覆压力超过膨胀应力,此时试样遇水不发生膨胀变形,反而出现明显的湿陷现象;当压实度大于96%后,即使上覆压力超过膨胀应力,试样遇水后也不发生湿陷现象,膨胀变形随上覆压力增大而趋于稳定值;(2)试验段弱膨胀土的膨胀应力随初始含水率的增加先增大后减小,出现膨胀应力峰值;(3)随着循环胀缩级数的增加,弱膨胀土的胀缩特性迅速降低,在循环级数达到4时,其胀缩特性就趋于稳定。上述3方面的膨胀特性充分表明,该弱膨胀土的膨胀特性与孔隙结构有着密切的关系  相似文献   
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