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1.
目前,在世界500强企业中,企业资源计划(Enterprise Resource Planning,简称ERP)的应用非常普遍,ERP管理理念的体现也非常充分,ERP软件数据的积累和分析为公司的远景规划提供了强有力的支持。  相似文献   

2.
随着计算机技术和管理科学的发展,企业资料计划(ERP)已在生产企业中得到了普遍应用,分布式组件对象技术基于面向对象思想,支持多层客户机/服务器的网络计算模式,允许应用之间相互通信;Java语言具有一次开发,到处运行的特点,这使得运用Java/CORBA技术实现ERP具有无可比拟的优越性,本文作者介绍了一个应用实例-东方炼油厂ERP项目,设计采用了基于Web CORBA Java分布式组件技术的方案,在项目的实施过程中取得了良好的应用效果。  相似文献   

3.
乘车沿着邢台市钢铁南路向南行两公里,便来到这家拥有十年信息化建设历史的钢铁企业——邢台钢铁有限责任公司(下称邢钢)。透过一排整齐的树木,可以看到邢钢正在建设中的新办公大楼,这里也是邢钢未来公司整体ERP系统的信息中心所在。邢钢副总经理戴鹤祥每每望向这栋楼,眼中总会流露出无限欣慰。  相似文献   

4.
美国地质调查局对美国大约99%的原始资源量在2 t以上的金矿、85 t以上的银矿、50000 t以上的铜矿、30000 t以上的铅矿和50000 t以上的锌矿进行了统计.从1996年的全国矿产资源评价开始,美国地调局系统地建立了这些矿床的数据库,统称之为"主要"矿床.截止至1996年12月31日,该数据库已收录了1118条单个矿床或矿区的记录.对于这种规模的数据库的维护、更新和分析要比管理诸如"矿产资源数据系统"和"矿业地区系统"等超过100000条记录的数据库容易得多.然而这个主要矿床数据库却包含了美国这几种金属矿床几乎所有的历史产量和已查明的保有资源量.约有30%的金、22%的银、42%的铜、39%的铅和46%的锌产于二战后发现的矿床中.即使在一个主要矿床的数据库中,也存在个别矿床中的历史产量及保有资源量分布不均匀的现象.每一种金属的最大10个矿床分别拥有了美国1/3的金、60%的银、68%的铜、85%的铅和75%的锌产量.从查明的保有资源量上看,最大的10个矿床分别占有43%的金、56%的银、48%的铜、94%的铅和72%的锌.每一种金属的主要矿床的查明资源量要低于1996年全国矿产资源评价对未发现矿床资源量估计的平均值.已查明资源量与累积的历史产量大体相当.假设未发现矿床中也有基本相同的资源量比例,将有大量的主要矿床有待发现.  相似文献   

5.
盐湖硼、锂、锶、氯同位素地球化学研究进展   总被引:5,自引:1,他引:4  
吕苑苑  郑绵平 《矿床地质》2014,33(5):930-944
盐湖作为盐矿资源的重要载体和富集区,探讨其矿物质来源及富集规律,不仅为盐湖的形成、演化及成盐成矿规律研究奠定了基础,也为盐湖资源评价及合理的开发利用提供了科学依据,具有重要的理论和现实意义。近年来,随着同位素地球化学的发展,同位素在盐湖领域的研究成果也日益丰富,使盐湖研究的深度和广度也得到快速发展。文章简要概述了硼、锂、锶、氯同位素的分馏机理及其在盐湖研究领域的发展历程,重点介绍了国内外取得的主要成果和最新进展,探讨了存在的问题,以促进硼、锂、锶、氯同位素地球化学研究在中国盐湖领域的进一步发展。  相似文献   

6.
姚继军 《岩矿测试》2008,27(5):403-404
利用快速自动进样器(FAST)可实现土壤、水、废水、血液、尿液的等离子体发射光谱(ICP-OES)和等离子体质谱(ICP-MS)快速分析,可以达到每7 s分析1个样品(每小时分析超过500个样品)。建立的方法对于环保、地质和医疗卫生的大面积普查取样和测量提供了强有力的手段;除改善分析速度外,还减小了记忆效应,改善了检出限,加标回收率在96.8%~102.0%。1快速自动进样器的工作原理快速自动进样器(FAST)由进样系统硬件和定时控制软件所组成。与传统的自动进样器相比,FAST做了如下改进(见图1和图2)。(1)样品提升采用真空提取,样品从不与蠕动泵的泵管接触。(2)样品充满定量环后,采用切换  相似文献   

7.
《地球科学进展》2005,20(9):F0003-F0003
实行开放式的办所策略,加强对外学术交流和科技合作,广泛吸纳国内外最新研究成果,瞄准世界前沿领域,不断拓宽研究领域,提升科技竞争力。干旱所设立了“干旱气象科学研究基金”,面向国内外相关科研机构开放。以甘肃省干旱气候变化与减灾重点实验室为合作平台,初步实现了产学研的结合,实现了科技资源的优化配置。积极参加各类高水平的国际国内学术会议,邀请国外专家学者来所开展学术交流和访问,与澳大利亚气象局等国外机构签署了国际合作协议。  相似文献   

8.
《新疆地质》2002,20(1)
2001年10月25日至11月30日,中欧亚岩相—古地理、构造、复原及地质生态图集编辑委员会和执行负责人会议分别在阿拉木图、比什凯克和莫斯科举行.来自中国、哈萨克斯坦、俄罗斯、乌孜别克斯坦、阿塞拜疆和吉尔吉斯斯坦的24位专家到会.中国新疆地质矿产勘查开发局专家董连慧、宋志齐和侯启尧参加了阿拉木图会议,会议由哈萨克斯坦南哈地质公司自然资源研究所主持,召集人为该所地质学家O.A.费多连科. 会议最终校定了已编辑完成的《中欧亚岩相—古地理、构造、复原及地质生态图集》,对提出的问题共同作出了修改方案,该图集2000年曾在巴西召开的第…  相似文献   

9.
岩爆、冲击地压的定义、机制、分类及其定量预测模型   总被引:6,自引:0,他引:6  
引述了若干国际权威学者关于岩爆的机制和定义的论述,在此基础上,依据岩爆发生的不同机制,将岩爆分为断层滑移或者剪切断裂所导致的断裂滑移型和岩石破坏导致的应变型岩爆,并结合事故案例,分析了应变型和滑移型两类岩爆及冲击地压的发生机制和特点。在机制分析的基础上,介绍了岩(煤)柱应变型岩爆和围岩应变型岩爆以及断裂滑移型岩爆定量预测的研究成果,其中,包括作者利用非欧几何模型研究非协调变形影响后对应变型岩爆进行了定量预测和数值模拟的新研究成果。  相似文献   

10.
本法是在样品中加入适量的缓冲剂,使难发挥元素Be形成易挥发的氟化物,与B、Pb、Mo、Sn、Cu、Ag、Zn等元素在同一时间内蒸发,利用深电孔极的分馏效应,有效地降低光谱背景以及被测元素的检出限。加入内标元素,提高了方法的准确度和精密度。采用深孔电极,取样量大,代表性好。一次摄谱,同时检测多个元素,大大提高了工作效率,又减少了测试费用。方法操作简便,适合于大批量样品的测试。检出限ω(B)/10-6分别达到:Be:0.50、B:0.91、Sn:0.50、Ag:0.02等,均满足《覆盖区多目标地球化学调查样品测试及质量监控暂行规定》规定。  相似文献   

11.
Komatiites are mantle-derived ultramafic volcanic rocks. Komatiites have been discovered in several States of India, notably in Karnataka. Studies on the distribution of trace-elements in the komatiites of India are very few. This paper proposes a simple, accurate, precise, rapid, and non-destructive wavelength-dispersive x-ray fluorescence (WDXRF) spectrometric technique for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites, and discusses the accuracy, precision, limits of detection, x-ray spectral-line interferences, inter-element effects, speed, advantages, and limitations of the technique. The accuracy of the technique is excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Zr, Nb, Ba, Pb, and Th and very good (within 4%) for Y. The precision is also excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th. The limits of detection are: 1 ppm for Sc and V; 2 ppm for Cr, Co, and Ni; 3 ppm for Cu, Zn, Rb, and Sr; 4 ppm for Y and Zr; 6 ppm for Nb; 10 ppm for Ba; 13 ppm for Pb; and 14 ppm for Th. The time taken for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in a batch of 24 samples of komatiites, for a replication of four analyses per sample, by one operator, using a manual WDXRF spectrometer, is only 60 hours.  相似文献   

12.
最新的流行病学研究表明,空气中较高浓度的悬浮细颗粒可能对人类的健康有不利的影响。根据该项研究显示,由于心脏病、慢性呼吸问题和肺功能指标恶化而导致死亡率的升高与细尘粒子有关。这些研究结果已经促使欧盟于1999年4月出台了限制空气中二氧化硫、二氧化氮、氧化氮、铅和颗粒物含量的法案(1999/30/EC),对各项指标包括对可吸入PM10颗粒的浓度提出了新的限制性指标。PM10颗粒是指可以通过预分级器分离采集的气体动力学直径小于10μm的细颗粒。目前研究的兴趣重点逐步偏向PM2.5这些更细微颗粒物,PM2.5这种颗粒物对健康有明显的不利影响。在欧盟指令2008/50/EC中,对PM10和PM2.5都提  相似文献   

13.
This paper reports the first results of a study of 11 isotope systems (3He/4He, 40Ar/36Ar, 34S/32S, 65Cu/63Cu, 62Ni/60Ni, 87Sr/86Sr, 143Nd/144Nd, 206–208Pb/204Pb, Hf–Nd, U–Pb, and Re–Os) in the rocks and ores of the Cu–Ni–PGE deposits of the Norilsk ore district. Almost all the results were obtained at the Center of Isotopic Research of the Karpinskii All-Russia Research Institute of Geology. The use of a number of independent genetic isotopic signatures and comprehensive isotopic knowledge provided a methodic basis for the interpretation of approximately 5000 isotopic analyses of various elements. The presence of materials from two sources, crust and mantle, was detected in the composition of the rocks and ores. The contribution of the crustal source is especially significant in the paleofluids (gas–liquid microinclusions) of the ore-forming medium. Crustal solutions were probably a transport medium during ore formation. Air argon is dominant in the ores, which indicates a connection between the paleofluids and the atmosphere. This suggests intense groundwater circulation during the crystallization of ore minerals. The age of the rocks and ores of the Norilsk deposits was determined. The stage of orebody formation is restricted to a narrow age interval of 250 ± 10 Ma. An isotopic criterion was proposed for the ore-bearing potential of mafic intrusions in the Norilsk–Taimyr region. It includes several interrelated isotopic ratios of various elements: He, Ar, S, and others.  相似文献   

14.
本文介绍样品经四硼酸锂熔融制成玻璃小饼。采用Lachance模式和理论a系数来校正元素间的效应,由3080E型X-射线荧光谱仪和DF-350B数据处理系统完成硅酸盐中十三个项目的测定。  相似文献   

15.
本文拟定了一种以熔融法制备样片,用X射线荧光光谱测定硅酸盐类样品中Si、Fe、Al、Tj、Mn、Ca、Mg、K、Na、P等元素的分析方法。在对不同靶材X光管和分光晶体实验对比的基础上,选择了最佳的测量条件。该法具有快速、准确,测量范围广,检测限低,价格便宜等优点。经过近百个各种类型标样或管理样品的分析对比表明,本法不仅适用于硅酸盐类岩石样品的分析,还适用于铁矿、铝土矿、碳酸盐类岩矿样品以及水泥、耐火材料等样品的分析。  相似文献   

16.
Mining induced subsidence can significantly affect mining costs where major surface facilities and natural environment need to be protected. Overburden grout injection is a technology used to control coal mine subsidence by injecting the mine waste material extracted from the coal back into the inter-burden rock during longwall mining. The flowing slurry is here categorised as a nonlinear viscous cohesive (Bingham plastic) fluid. During longwall mining the grout slurry is pumped into the separated beds of the rock mass through a central vertical borehole, which is drilled deep into the inter-burden rock strata above the coal seam. However, a blockage can occur in the injection system when the slurry velocity falls below a certain critical threshold velocity, indicating a material phase change from cohesive-viscous to cohesive-frictional. In situ field injection tests through boreholes have been simulated at a smaller scale at the CSIRO laboratory in Brisbane by pumping the slurry through a radial disk (gap = 4 mm) from its centre. Laboratory experiments indicate a general, nonlinear, cohesive, viscous, frictional model for shear behaviour of the slurry, in which the material shear parameters are functions of the disk radial distance. Complete dimensional and dimensionless analytical solutions have been developed based on an approach related to Bingham–Herschel–Bulkley fluid mechanics. The derived formulae include relations for minimum pump pressure, local pressure and pressure gradient, wall shear stress, volume rate, velocity and velocity gradient. The theoretical results match the experimental measurements. The experiments covered slurries with maximum particle sizes of 0.5 to 2 mm with about 50% being larger than 100 µm. The viscosities at the various solids concentrations were measured with a standard torsion viscometer. This study differs from the previous research in several distinct aspects, namely, consideration of the variable shear parameters rather than fixed values, inclusion of total nonlinear behaviour, and implementation of a friction function to mimic behaviour of the deposited and consolidating stiff slurry, which can cause a significant pressure rise as a result of the increased shear resistance.  相似文献   

17.
18.
Between 1985 and 1991, two new mountain protected areas (MTNPA) covering more than 35,000 km2 and based on participatory management models — the Makalu-Barun National Park and Conservation Area, Nepal, and Qomolangma Nature Preserve, Tibet Autonomous Region — were successfully established through the collaborative efforts of Woodlands Mountain Institute and conservationists in China and Nepal. Characteristics common to both projects include the importance of establishing (1) effective rationales, (2) local support constituencies, (3) a senior advisory group, (4) a task force, (5) linkages between conservation and development, and (6) fund raising mechanisms. The lessons derived from the experiences of Woodlands Mountain Institute are of significant value to others in preserving MTNPA. Increased collaboration and communication between all interested in conservation, however, will remain a critical component for expanding mountain protected area coverage to throughout the world.  相似文献   

19.
岩石密度和超高压岩石折返速率   总被引:1,自引:3,他引:1  
在常温常压条件下对中国大陆科学钻CCSD主孔100-3000米岩心样品进行了密度测量,建立了密度连续剖面,并界定了不同超高压岩石的密度值。通过对比高温高压物性实验资料,岩石密度随着退变程度增强而降低,榴辉岩密度变化序列为3.52g/cm3→3.49g/cm3→3.07g/cm3→2.93g/cm3。超高压长英质岩石密度变化序列为3.00g/cm→2.80g/cm3→2.65g/cm3。上述实验资料是讨论不同折返阶段岩石所受浮力的基础,为研究折返速率大小提供了基本参数。本文通过折返板块运动平衡时,上浮力与粘滞力平衡这一关系式,定量研究了大陆俯冲板块的折返速率,认为密度差产生上浮力从而引起折返,温度对板块折返速率的影响最为显著;密度差大小、折返角度、折返板块大小对折返速率也有直接的影响。定量模拟分析表明,在温度高于850℃时,板块的折返速率可以超过100mm/a;当温度降至700℃时,折返速率则低于1.5mm/a。作者认为在折返早期,温度较高,板块快速折返至60-70km榴辉岩相深度;随着传导散热,温度降低,板块以较慢的速率折返至中下地壳。折返速率的估算表明,浮力是板块折返第一阶段(从>100km深部折返至<40km的中下地壳)的主要驱动力。  相似文献   

20.
《Applied Geochemistry》2001,16(2):137-159
Five hundred and ninety-eight samples of terrestrial moss (Hylocomium splendens and Pleurozium schreberi) collected from a 188,000 km2 area of the central Barents region (NE Norway, N Finland, NW Russia) were analysed by ICP-AES and ICP-MS. Analytical results for Al, B, Ba, Ca, K, La, Mg, Mn, Na, P, Rb, Si, Sr, Th, U and Y concentrations are reported here. Graphical methods of data analysis, such as geochemical maps, cumulative frequency diagrams, boxplots and scatterplots, are used to interpret the origin of the patterns for these elements. None of the elements reported here are emitted in significant amounts from the smelting industry on the Kola Peninsula. Despite the conventional view that moss chemistry reflects atmospheric element input, the nature of the underlying mineral substrate (regolith or bedrock) is found to have a considerable influence on moss composition for several elements. This influence of the chemistry of the mineral substrate can take place in a variety of ways. (1) It can be completely natural, reflecting the ability of higher plants to take up elements from deep soil horizons and shed them with litterfall onto the surface. (2) It can result from naturally increased soil dust input where vegetation is scarce due to harsh climatic conditions for instance. Alternatively, substrate influence can be enhanced by human activity, such as open-cast mining, creation of ‘technogenic deserts’, or handling, transport and storage of ore and ore products, all of which magnify the natural elemental flux from bedrock to ground vegetation. Seaspray is another natural process affecting moss composition in the area (Mg, Na), and this is most visible in the Norwegian part of the study area. Presence or absence of some plant species, e.g., lichens, seems to influence moss chemistry. This is shown by the low concentrations of B or K in moss on the Finnish and Norwegian side of the (fenced) border with Russia, contrasting with high concentrations on the other side (intensive reindeer husbandry west of the border has selectively depleted the lichen population).  相似文献   

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