排序方式: 共有52条查询结果,搜索用时 23 毫秒
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内蒙古东胜地区高岭土矿床的岩石矿物学研究 总被引:4,自引:1,他引:3
内蒙古东胜地区高岭土矿床产于鄂尔多斯盆地东北缘上三叠世—中侏罗世煤系地层中 ,该矿包括 T3延长组顶部的 B矿层和 J2 延安组顶部的 A矿层。经薄片鉴定、阴极发光、扫描电镜、电子探针、X光衍射综合分析认为 ,B矿层的原岩为富含钾长石的长石石英砂岩 ,较近源沉积 ,经风化淋滤形成微风化带、不完全风化带、完全风化带及顶部植被带。完全风化带内赋存着化学成分纯、Fe和 Ti含量少的高岭石 ,其矿石结晶度较好 ,以蠕虫状、折扇状高岭石为主 ;A矿层原岩的矿物特征与 B矿层类似 ,但其母岩有 B矿层的物质加入 ,夹有泥岩型高岭土和少量酸性火山物质 ,另外高岭石的结晶度稍次于 B矿层 相似文献
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陆相干旱盆地充填的沙漠层序--以鄂尔多斯盆地白垩系为例 总被引:8,自引:0,他引:8
本文通过对鄂尔多斯盆地白垩系的野外考察,认为该地层为一特殊类型的陆相层序--沙漠层序。利用实地考察剖面,建立了该地层的层序地层框架,提出沙漠扩张体系域和沙漠收缩体系域的概念及体系域的构成单元,认定在垂向上具有三次完整的层序旋回,并在空间上描述了各沉积体系的配置方式及不同时期各成因单元的叠加型式,以鄂尔多斯盆地白垩系为对象对沙漠层序的发育演化特征作了综述。最后,对沙漠层序的控制因素作了粗浅探讨。本文对完善陆相盆地充填层序的研究具有较大的理论意义。 相似文献
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“偏高岭石—碱—水”体系中4A沸石晶体生长规律及其机理探讨 总被引:9,自引:0,他引:9
煅烧高岭土与氢氧化钠的水热反应体系中,偏高岭石不仅为4A沸石的形成提供了物质基础,而且为晶核的形成提供了有利界面。4A沸石的晶核总是优先形成于发生了溶解的偏高岭石表面,而晶体生长的方式则受偏高岭石颗粒大小的影响。随着晶体的大量生长,偏高岭石逐渐消失,与此同时,产生了二次成核作用,晶体在先成的4A沸石晶体表面生长,形成双晶。在整个反应过程中,液相中的[Al2O3]及[SiO2]浓度的变化与4A沸石晶体生成具有一定对应关系。这表明,偏高岭石不断溶解,固相的Al2O3·2SiO2不断转化为液相的Al2O3和SiO2。沸石晶体的生成是以液相各组分浓度的过饱和为动力的,为液相生成机理 相似文献
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从某种程度上说,对煤的研究仍然是一个薄弱环节。以往的工作更多的是侧重指导生产及利用方面,而对涉及煤的成因的基本 相似文献
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PAUL GELADI Research Group for Chemometries University of Ume S- Ume Sweden Center for Peat Research Box S- Ume SwedenKIM ESBENSEN Norwegian Computing Center PB Blindern N- Oslo Norway 《地理学报(英文版)》1991,(2)
Regression between two blocks(usually called‘dependent’or Y and‘independent’or X)of data is a veryimportant scientific and data-analytical tool.Regression on multivariate images is possible and constitutesa meaningful addition to existing univariate and multivariate techniques of image analysis.The regressioncan be used as a modeling tool or for prediction.The form of the regression equation chosen is dependentupon problem specification and information at hand.This paper describes the use of principal componentregression(PCR).Both model building and prediction are presented for continuous Y-variables.The finalgoal is to supply new image material that can be used for visual inspection on a screen.Also,visual toolsfor diagnosis of model and prediction are provided,often based on derived image material.Examplesof modeling and prediction are given for six channels in a seven-channel satellite image 相似文献
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在对“成功的”地震预报赋予统计显著性对,有许多潜在陷井,包括对地震姓的随机模型的敏感性问题,用于描述一次地震所用参数之间的相关性问题以及对预报的随机替代模型问题等。对这些困难没有简单的解决办法,但是很清楚的是:人们假定了地震的位置和大小是独立的,但如果它们不独立则可导致预报在统计上是显著的错误的印象,并且,主震在时间上(和空间上)符合泊松过程的假定可使偶然性预报上呈现显著而使有效预报统计上不显著, 相似文献
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Water is rapidly becoming a critical factor in the development of Nepal despite the fact that it has one of the greatest hydro-power potentials in the world. The country is faced with three key water issues: hazardous hydro-power development, problems with community water supply and pollution, and shortages of irrigation water. Both the environmental settings and the socio-economic conditions have contributed to these problems which are now widespread and alarming. Environmental factors have not been taken seriously as shown in the largest existing hydropower reservoir, which has recently lost much of its storage capacity in a single unusual storm. Shortages in water supplies in the capital city are also reaching crisis proportions both in terms of quantity and quality. The widespread lack of irrigation water in the Middle Mountains during the dry season has serious implications for the future food supplies of the largely rural population. Some of these problems result from a rapidly expanding population living in a very marginal environment, an ineffective government organization and an international community that is mostly self-serving, focussing on large projects with little concern for local needs. The degradation of water resources is putting the food supplies and health of a large part of the population at risk. 相似文献
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