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91.
从地质、技术经济的角度讨论拉拉铜矿合理矿床工业指标。通过分析论证认为调整矿床工业指标有利于满足矿山扩大规模开发的需要,提高矿山开发的经济效益,解决矿山生产过程中的实际问题。 相似文献
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93.
贵州水城观音山铁矿成矿构造体系分析 总被引:1,自引:0,他引:1
文章应用地质力学的理论和方法,通过对贵州水城观音山铁矿区内结构面力学性质的鉴定,将区内构造形迹划分为三种类型的构造体系,并在此基础上,通过对矿区内矿床的控矿构造型式进行分析,确立了属于威宁弧形构造的北西构造带为成矿期构造体系。 相似文献
94.
存款保险制度是维护金融体系安全的重要机制,结合我国金融业目前的现状,说明了在我国建立存款保险制度的必要性,然后分析了存款保险制度的几项重要功能,并在此基础上提出了一些在我国建立存款保险的制度设计思想。 相似文献
95.
王赫莹 《沈阳工业大学学报》2004,26(5):491-494
通过滑动磨损试验,使用显微硬度计、差热分析仪、SEM和X—ray衍射仪等仪器,研究Ni—W—P合金镀层的磨损特性及磨损机制.结果表明,Ni—W—P合金镀层经400℃时效显微硬度达到Hv1325,磨损率为6.4mg/h.cm.在边界润滑条件下,镀层的磨损机制为粘着磨损与磨粒磨损并存。 相似文献
96.
S. Chatterjee 《Wear》2006,261(10):1069-1079
Solid particle erosion (SPE) behaviour of different hardfacing electrodes deposited on gray cast iron (ASTM 2500) was studied using quartz sand and iron ore as erodent particles. Erosion test was carried out as per ASTM G76 test method. Considerable differences in erosion rates were found among different hardfacing electrodes at normal impact. Both volume fraction of carbides and type of carbides played an important role in the erosion behaviour of the deposits when quartz sand was used as erodent particles. On the other hand, only volume fraction of carbides irrespective of carbide type mainly controlled the erosion rate of the same deposits when iron ore was used as erodent particles. Such difference is attributed due to difference in metal removal mechanisms by the two erodent particles used. Hard quartz sand particles were capable of causing damage to most of the carbides while relatively softer iron ore particles were unable to fracture any carbides present in the microstructures. Furthermore, relatively brittle matrix led to high erosion rate which is significant in case of quartz sand as erodent, but not in case of iron ore particles. Like abrasion resistance, hardness is not a true index of erosion resistance of hardfacing deposits. 相似文献
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98.
针对2002年铜地质勘查规范中一般工业指标存在的问题,基于大量实际生产数据,对铜矿床实际采用的边界品位指标、最低工业品位、矿床平均品位、最小可采厚度、夹石剔除厚度、开采技术条件等进行研究,论证了铜矿床的一般工业指标,并首次明确了铜矿床工业指标的适用条件,解决了铜矿床一般工业指标体系应用不一致和指标区间取值主观性的问题。 相似文献
99.
The mine improvement of rock mass rating (M-IRMR) evaluation method was put forward based on the existing theory of the rock quality classification and the stability evaluation in the undersea deposit of Sanshandao Gold Mine, China. The M-IRMR evaluation method includes 9 evaluation indexes which are rock compressive strength, rock quality index RQD, joint spacing, joint state, groundwater state, joint direction, ground stress, blasting vibration, and exposed area, respectively. During the evaluation process, according to the special features of the undersea deposit, the rock mass rating (RMR) method was used as the foundation, and the four geological parameters (i.e., rock compressive strength, rock quality index, joint spacing, and ground stress) were modified. The computing methods of the two engineering factors (blasting vibration and exposed area) were presented. The M-IRMR rock quality classification and stability evaluation method was applied in the level of −420 to −690 m in the undersea deposit of Sanshandao Gold Mine and the classification results were consistent with the actual situations, which can provide a scientific basis for choosing the suitable mining method and stope support system of the undersea deposit. 相似文献
100.
Natalie Armitage 《Material Religion》2018,14(2):218-234
AbstractThrough experiences of two different museum spaces the nature of material objects of Vodou are considered. How can the complexities of ritual deposits, assemblage, and continued interaction that are present within a religious space, such as the Vodou altar, be demonstrated to outsiders via a curated space? The materiality of these objects and accumulations is considered and the question is posed as to their importance in the understanding of the nature of Vodou worship. Can a traditional museum setting that favours manufactured objects over the spontaneous ritual deposit and repurposed object convey the intricacy of the material culture of Vodou if it negates the inclusion of these artefacts? 相似文献