三类高强度悬式瓷绝缘子的成分和物相分析     

龚国洪  唐荣炳  尹祚莹  邓华兴  伍正平 《矿物岩石地球化学通报》2002,21(3):174-176

为探讨高原牌70kN和进口120，210kN瓷绝缘子的成分和结构性能，中采用原子吸收光谱（AAS）和X射线衍射（XRD）方法，对三类产品进行了检测。结果表明，有效成分除K2O外，70kN和210kN的SiO2,Al2O3,Fe2O3含量接近，主晶相基本相同，有刚玉，莫来石、石英和长石等；结晶相总量：70kN35%，120kN40%,210kN48%，这表明机械强度愈大，结晶相含量愈高，只需调整70kN原样的部分成分，粒度和工艺，即生产出高等级（如210kN)瓷绝缘子。  相似文献   

Neoproterozoic to Early Cambrian history of an active plate margin in the Teplá–Barrandian unit—a correlation of U–Pb isotopic-dilution-TIMS ages (Bohemia, Czech Republic)     

W. Drr  G. Zulauf  J. Fiala  W. Franke  Z. Vejnar 《Tectonophysics》2002,352(1-2)

The Teplá–Barrandian unit (TBU) of the Bohemian Massif shared a common geological history throughout the Neoproterozoic and Cambrian with the Avalonian–Cadomian terranes. The Neoproterozoic evolution of an active plate margin in the Teplá–Barrandian is similar to Avalonian rocks in Newfoundland, whereas the Cambrian transtension and related calc-alkaline plutons are reminiscent of the Cadomian Ossa–Morena Zone and the Armorican Massif in western Europe. The Neoproterozoic evolution of the Teplá–Barrandian unit fits well with that of the Lausitz area (Saxothuringian unit), but is significantly distinct from the history of the Moravo–Silesian unit.The oldest volcanic activity in the Bohemian Massif is dated at 609+17/−19 Ma (U–Pb upper intercept). Subduction-related volcanic rocks have been dated from 585±7 to 568±3 Ma (lower intercept, rhyolite boulders), which pre-dates the age of sedimentation of the Cadomian flysch ( t chovice Group). Accretion, uplift and erosion of the volcanic arc is documented by the Neoproterozoic Dob í conglomerate of the upper part of the flysch. The intrusion age of 541+7/−8 Ma from the Zgorzelec granodiorite is interpreted as a minimum age of the Neoproterozoic sequence. The Neoproterozoic crust was tilted and subsequently early Cambrian intrusions dated at 522±2 Ma (T ovice granite), 524±3 Ma (V epadly granodiorite), 523±3 Ma (Smr ovice tonalite), 523±1 Ma (Smr ovice gabbro) and 524±0.8 Ma (Orlovice gabbro) were emplaced into transtensive shear zones.  相似文献   

铅锌矿山开发导致的重金属在环境介质中的积累   总被引：35，自引：4，他引：35  

杨元根  刘丛强  张国平  吴攀  朱维晃 《矿物岩石地球化学通报》2003,22(4):305-309

以连续提取法和相关性分析研究了土法冶炼锌、铅锌和矿山开采导致的重金属在废渣及环境介质土壤、溪流沉积物中的积累，并分析了其环境危害性。结果显示，贵州赫章土法炼锌导致的重金属Pb、Zn、Cd在环境介质中的积累相当高。水城杉树林铅锌矿山开采引起的重金属积累则相对较低，但也明显高于背景值；土壤和沉积物中的铁矿物对重金属有强烈的固定作用。除残渣态外，Pb、Zn在土壤、炼锌废渣中主要呈铁锰氧化物结合态，沉积物中则为碳酸盐结合态。可交换态Pb、Zn含量变异较大，但在炼锌废渣、土壤中含量明显高于河流沉积物，暗示铅锌矿开发对土壤环境的潜在危害更大。  相似文献   

晋祠泉断流与地下水资源保护关系   总被引：4，自引：0，他引：4  

黄皓莉 《中国煤田地质》2003,15(2):26-28

通过对晋祠泉域岩溶地下水水文地质条件的分析,阐述了晋泉形成机理和断流原因,认为晋泉断流是多种因素的综合效应。说明地下水资源保护是一项系统工程,应采取统一的、科学的、多层次的全面管理,才能有效地保护有限的地下水资源,唤醒人们在进行经济建设的同时,要注意保护我们赖以生存的地球环境。  相似文献   

滚 滑 复 合 轴 承 研 究     

田红平  张福润  杨楚民 《探矿工程》2003,30(1):60-62

针对牙轮钻头的滑动轴承和滚动轴承在实际工作中所存在的问题，提出一种牙轮钻头滚滑复合轴承，对滚滑复合轴承结构进行有限元对比分析、模拟对比试验和钻头现场验证实验，表明滚滑复合轴承是一种较先进的创新性轴承。  相似文献   

机械卡盘设计中的计算误差分析与应用          下载免费PDF全文

陈宝杰  卜长根 《探矿工程》2003,30(3):30-32,34

通过对普通机构二维力因素影响的分析，利用修正公式计算求值，以修正单因素影响最大值计算所产生的误差。利用这一计算方法，对CD—3型钻机卡盘进行了计算，得到了正确的设计结果，说明用修正公式对多因素影响采用单因素影响最大值计算进行修正是可行的。  相似文献   

几个矿床技术经济评价问题探讨     

张福祯 《化工矿产地质》1997,19(1):58-62

矿床技术经济评价在地质勘查工作中占有重要地位。目前编写地质勘查报告都必须包括技术经济评价章节。但我国矿床技术经济评价的理论和方法还存在一些问题，某些评价方法和基本概念还不够统一。通过对投资回收期、净现值、总现值、销售成本、经营成本等参数的研究认为，矿床技术经济评价要进一步规范化。  相似文献   

Hazard mapping based on macroseismic data considering the influence of geological conditions   总被引：1，自引：0，他引：1  

M. L. Sousa  C. S. Oliveira 《Natural Hazards》1996,14(2-3):207-225

The object of this study is to consider directly the influence of regional geological conditions on the assessment of seismic hazard. It is assumed that macroseismic data at individual locations contain, in an average way, the influence of geological conditions.A Data Base referring to 199 historical (5) and instrumental (194, in the 1947–1993 period) events with macroseismic information in 1195 locations of Portugal was built. For any given seismic event, whenever macroseismic information was available at a location (town, village, etc.), an EMS-92 intensity value was estimated. To each one of those locations a geological unit, representing the most common type of soil, was assigned, based on the Geological Portuguese Map at a scale 1:500 000; the geological units were grouped into three categories: soft, intermediate and hard soils.The Data Base was used to determine the attenuation laws in terms of macroseismic intensity for the three different geological site conditions, using multiple linear regression analysis. The reasonability of the laws was tested by (i) checking residual distributions and (ii) comparing the map of isoseismals of important earthquakes with the isoseismals generated by the attenuation curves derived for each one of the three different soil classes, taking into consideration the soil class of each site. The main results of attenuation modeling are: high dispersion on macroseismic intensity data; all the models predict intensity values, for short hypocentral distances, lower than the ones observed; and for some important analyzed earthquakes and for the observed range of distances, the models confirm the expectancy that macroseismic intensity increases from hard to soft soil.The approach to obtain the hazard assessment at each location consisted in the use of the attenuation law specifically derived for the class of soil of that particular location. This method, which considers the influence of the regional geology, was illustrated with the mapping of hazard for the country for several return periods. Comparison with previous maps not taking into consideration the regional geological conditions emphasizes the importance of this new parameter. It can be concluded that (i) soil segmentation is clearly the cause for hazard increase in the region to the north of Lisbon, especially at sites with soft and intermediate soils as the ones in lower Tagus valley; the maximum increase on hazard is, in any case, less than one degree; (ii) when geological conditions are disregarded in the attenuation regression analysis, hazard pattern is similar to the one obtained for the case of hard soil everywhere.  相似文献   

建设用地地质灾害危险性评估中几个问题的思考   总被引：7，自引：3，他引：7  

金德山 《中国地质灾害与防治学报》2004,15(4):101-103

结合工作实践，就建设用地地质灾害危险性评估及其成果审查工作中经常遇到的5个问题——评估灾害类型的确定原则，评估区环境条件分析深度的把握，现状、预测及综合地质灾害危险性评估内容的侧重点，土地适宜性评价的依据以及优秀评估成果的判定标准，提出了个人的理解和认识。供从事类似工作的同志参考。  相似文献   

中国大陆科学钻探主孔1200米构造柱及变形构造初步解析   总被引：31，自引：20，他引：31  

许志琴张泽明  刘福来杨经绥唐哲民  陈世忠柴耀楚李天福  陈方远 《岩石学报》2004,20(1):53-72

在利用成象测井资料准确地恢复岩心空间位置的基础上，建立了位于江苏省东海县毛北村的中国大陆科学钻探主孔岩心1200m精细构造柱。划分了由榴辉岩与超镁铁质岩组成的第一岩性-构造单元及由副片麻岩夹榴辉岩与超镁铁质岩透镜体组成的第二岩性-构造单元，自上而下岩石的面理产状由向东陡倾变为向南东缓倾。第一岩性-构造单元的榴辉岩与超镁铁质岩是毛北榴辉岩杂岩体的组成部分，在榴辉岩中发现以南北向拉伸线理及由北往南的剪切指向为特征的超高压变质岩早期变形举止。位于第二岩性一构造单元下部(770-1130m深度)300多米厚的韧性剪切带是地表出露的毛北韧性剪切带在孔下的延伸，剪切应变及石英组构分析表明，在伴随的退变质角闪岩相一绿帘角闪岩相一绿片岩相的转换过程中，剪切应变由自SE往NW的“逆冲”转为NW向SE的正向滑移。结合钻孔围区地质，重塑了上部由毛北榴辉岩杂岩体与副片麻岩围岩组成的轴面向SE倾斜的同斜倒转褶皱系，以及下部为韧性剪切带的构造模型。钻孔验证了VSP地震反射剖面中850-1200m深度的强反射层与韧性剪切带相吻合。结合苏鲁超高压变质地体的折返构造的研究，提出该构造模型的成因与折返阶段超高压变质地体的斜向上的挤出及后折返阶段的穹隆形成有关。  相似文献