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641.
安庆铜矿地质储量管理系统的研究与开发   总被引:1,自引:0,他引:1  
地质储量是矿山企业赖以生存和发展的基础,对有限的地质储量能否进行有效管理直接影响矿山企业的经济效益和持续发展.近年,国际上发达采矿国家已纷纷利用数字信息技术来改造和提升其采矿业,不仅变革了传统矿业沿袭百年的生产工艺和组织管理模式,而且极大地提高了矿山企业的生产效率和安全水平.文章针对安庆铜矿的具体情况,详细讨论了建立地质储量管理系统的技术方案与路线,进行了数据库概要设计,讨论了实现系统功能的一些关键技术.  相似文献   
642.
河北平原区土壤磁性调查及农业应用的初探   总被引:1,自引:2,他引:1  
土壤磁性数据将是生物磁学农业应用的基础。通过对河北省平原区某地土壤样品的磁性测试,试图分析河北省平原区的土壤磁性背景,探讨生物磁学农业应用的途径。  相似文献   
643.
李远  李振  乔兰  李淼 《岩土力学》2014,35(Z1):173-180
针对统一强度理论(UST)拟合非线性强度的局限和岩土材料强度特点,提出拟合岩土非线性强度特征的脆性剪切分析方法,建立了过渡式双线性强度分解公式。以脆断、剪切双重破坏机制,解释Hoek-Brown准则的非线性特征机制,并推导出体现岩石、岩体类材料非线性强度特征的脆剪强度公式。Mine-by隧道和北山花岗岩强度数据分析显示,在岩体折减强度、试验数据直接拟合实例分析中,脆剪强度与Hoek-Brown强度相关性系数均在0.98以上,在该基础上建立岩体非线性强度脆剪分析的双线性过渡式,并提出对应的统一强度理论形式,实现统一强度理论在拟合岩土非线性强度准则中的扩展。  相似文献   
644.
Near-surface atmospheric dust in Changsha city of China was analyzed in terms of morphological and geochemical composition. Morphological and chemical composition of the dust particles were analyzed by environmental scanning electron microscopy coupled with an energy-dispersive X-ray analyzer. Results indicated that the atmospheric dusts were mainly composed of spherule, plate, irregularly shaped and agglomerate, which contains variable sizes and amounts of particles. The dust particles could be categorized into five groups based on their chemical characteristic: Al-, Si-, Ca-, C-rich particles and aggregate. These particles and aggregate could be directly related to nearby polluting activities, such as building construction, traffic emission and coal combustion. The X-ray diffraction results show that the main minerals for atmospheric dust are gypsum, quartz and calcite. Mica, halloysite, montmorillonite, hematite, brushite, zeolite, sepiolite, feldspar, alite, dickite, SiS2, Fe6(OH)2CO3, FeSO4, CdSO4, Pb(NO)2O3, Al2SO4(OH)4, As2O3SO3, (NH4)2SO4, NH4Cl, K(NH4)·Ca(SO4)2·H2O are also detected in samples. The identification of heavy metals shows that the concentrations of Cr (403.5?mg?kg?1), Cu (126?mg?kg?1), Zn (1541.5?mg?kg?1), Cd (2.5?mg?kg?1) and Pb (348?mg?kg?1) in the atmospheric dust are much higher compared to background value of soil. It indicates that the heavy metal (Cr, Cu, Zn, Cd and Pb) in the atmospheric dust is mainly due to human activities. The identification of main sources of atmospheric dust collected in typical areas can help to control the polluting sources in urban area.  相似文献   
645.
Principal component analysis (PCA) and independent component analysis (ICA) are linear feature extraction methods in terms of the second-order statistics and higher-order statistics and have good compatibility and complementarity. For the feature extraction of the hyperspectral remote sensing image, an approach of the combined PCA and ICA was followed in the real remote sensing classification applications. In this study, the weighted PCA-ICA method was introduced to extract the feature information from HJ-1A hyperspectral imager (HSI) image. And then the real airborne visible infrared imaging spectrometer (AVIRIS) image case was performed by the distance similarity measure. Experimental results on HJ-1A HSI and AVIRIS images indicate that the proposed method can get high average accuracy of 89.55% and kappa coefficient of 0.8101 than the typical methods under certain condition with a suitable number of eigenvectors and weighted values.  相似文献   
646.
The concentrations of heavy metals (Cr, Co, Ni, Cu, Zn, Pb, Cd, As, Hg, and Fe) in sediments of the Yangtze River, China, were investigated to evaluate levels of contamination and their potential sources. The lowest heavy metal concentrations were found in the source regions of the river basin. Relatively high concentrations of metals, except Cr, were found in the Sichuan Basin, and the highest concentrations were in the Xiangjiang and Shun’anhe rivers. All concentrations, except Ni, were higher than global averages. Principal component analysis and hierarchical cluster analysis showed that Zn, Pb, As, Hg, and Cd were derived mainly from the exploitation of various multi-metal minerals, industrial wastewater, and domestic sewage. Cu, Co, and Fe were derived mainly from natural weathering (erosion). Cr and Ni were derived mainly from agricultural activities, municipal and industrial wastewater. Sediment pollution was assessed using the geoaccumulation index (I geo) and enrichment factor (EF). Among the ten heavy metals assessed, Cd and Pb had the highest I geo values, followed by Cu, As, Zn, and Hg. The I geo values of Fe, Cr, Co, and Ni were <0 in all sediments. EF provided similar information to I geo: no enrichment was found for Cr, Co, and Ni. Cu, Zn, As, and Hg were relatively enriched at some sites while Cd and Pb showed significant enrichment.  相似文献   
647.
梁兰  徐有为 《黄金地质》1996,2(3):71-75
在聚四氟乙烯密封溶样罐中,岩石样品经盐酸,硝酸,氢氟酸,高氯酸加热溶解,保存了易挥发组分SiF4用热沸盐酸溶解Al,Ca,Mg的氟化物再生沉淀,用饱和硼酸溶液充分配合氟离子,制成的样品溶液在等离子直读光谱仪上,可快速同时测定了Si,Fe,Al,Ca,Mg,K,Na,Mn,Ti,P等10个造岩元素,方法准确可靠,已在日常检测工作中应用。  相似文献   
648.
江苏宜兴骆驼墩遗址地层7500~5400BC的海侵事件记录   总被引:1,自引:0,他引:1  
李兰  朱诚  林留根  赵泉鸿  史恭乐  朱寒冰 《地理学报》2008,63(11):1189-1197
在考古发掘基础上,野外共采集样品217个,对遗址地层剖面中63个样品进行了有孔虫、植物碎屑及种子化石等的鉴定分析,对4个地层相关样品进行了14C测年及相关分析。在第10层的泥炭层中发现底栖有孔虫2种1属,即压扁卷转虫(Ammonia compressiuscula)和近亲卷转虫相似种(Ammonia cff.sobrina),表明全新世以来骆驼墩遗址及其附近区域在马家浜文化出现之前的7500-5400BC之间曾经历过海侵事件;共发现植物化石9种450颗,鉴定结果共统计出4(科)属,即Polygonum sp.(蓼属未定种)、Scirpus sp.(藨草属未定种)、Najas sp.(茨藻属未定种)、Physalis sp.(酸浆属未定种),多属湖泊、沼泽等水生环境。  相似文献   
649.
Based on dynastic period division and AMS ^14 C dating performed on the sedimentary layers at Zhongba and Yuxi sites,and also the analysis of Na,Ca and Mg of 201 sedimentary samples from Zhongba site and that of Ca and Na in 47 sedimentary samples from Yuxi by using an inductively coupled plasma-mass spectrometry(ICP),we found that there were 35 time periods when the contents of Ca and Na were reversely correlated,i.e.whenever the content of Ca was the highest,the content of Na was the lowest,and vice versa. Among them,there were 21 time periods when the content of Ca was the highest,and Na was the lowest,indicating that there were about 21 prosperous periods of ancient salt production at Zhongba site since 3000BC.Other 14 time periods with the peak values of Na while the low values of Ca indicate 14 declined periods of salt production at Zhongba site since 3000BC.The conclusion obtained from the reverse relationship between Ca and Na contents in this paper is consistent with that"the salt production at Zhongba site started in the new stone age,developed in the Xia and Shang dynasties,reached at the heyday in periods from the Western Zhou to the Han Dynasties,maintained stable to develop in the Tang and the Song dynasties,and gradually declined after the Song Dynasty because the sea salt were conveyed into Sichuan region,however,still had production in the 1970s-1980s",educed from archeological exploration.All the above mentioned results indicate that there is a reverse relationship obviously between the contents of Na and Ca in sediments at Zhongba site for ancient salt production,which can be used to reveal the process of rise and decline of ancient salt industry at Zhongba site.  相似文献   
650.
UAV remote sensing images have the advantages of high spatial resolution, fast speed, strong realtime performance, and convenient operation, etc., and have become a recently developed, vital means of acquiring surface information. It is an important research task for precision agriculture to make full use of the spectrum, texture, color and other characteristic information of crops, especially the spatial arrangement and structure information of features, to explore effective methods for the cla...  相似文献   
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