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俄罗斯公布2003年的钻石开采量
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作者 岳萍 《中亚信息》 2005年第1期44-44,共1页
俄罗斯财政部新闻司透露,俄罗斯2003年共开采了3302万克拉钻石,价值约16.76亿美元。这是国家首次公开未加工钻石的开采及进出口数据。
关键词 俄罗斯 2003年 钻石开采 钻石出口
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Study on control of rock fragmentation at limestone quarry 被引量:2
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作者 SASAOKA Takashi SHIMADA Hideki +2 位作者 SASAKI Takayuki ICHINOSE Masatomo MATSUI Kikuo 《Journal of Coal Science & Engineering(China)》 2008年第3期365-368,共4页
The size distribution of a muck pile depends not on only the blasting standard but also on the mechanical properties,joint system,and crack density of the rock mass. As,the cracks in the rock masses are especially hea... The size distribution of a muck pile depends not on only the blasting standard but also on the mechanical properties,joint system,and crack density of the rock mass. As,the cracks in the rock masses are especially heavily developed at the limestone quar- ries in Japan,they,along with the joints,have a large impact on the effects of blasting, such as the size of the muck pile.Therefore,if the joint system and/or crack density in a rock mass can be determined and quantitatively evaluated,the blasting operation can be conducted more effectively,efficiently and safely.However,guidelines for designing ap- propriate blasting standards based on the rock mass conditions have not yet been scien- tifically developed.Therefore,blasting tests were conducted on different mines and faces, under different geological conditions and blasting standards,in order to determine the im- pacts of each factor on the effects of blasting.Summarized the results of a series of blast- ing tests and described the impacts of geological conditions on the size of the muck pile produced by blast. 展开更多
关键词 FRAGMENTATION blasting standard BLASTING borehole scoping
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Experimental and Parametric Design of Petroleum Back-pressured Hydraulic Impactor 被引量:1
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作者 袁光杰 姚振强 +1 位作者 陈平 黄万志 《Journal of Donghua University(English Edition)》 EI CAS 2005年第5期100-106,共7页
Percussive-rotary drilling technology was considered many years ago as one of the best approaches for hard rock drilling. It is a key for popularizing this technology on a large scale to design and make an impactor wi... Percussive-rotary drilling technology was considered many years ago as one of the best approaches for hard rock drilling. It is a key for popularizing this technology on a large scale to design and make an impactor with excellent performance. This paper presents a suit of method to design the percussive parameters for the oil or gas field by introducing the working principle of back-pressurod impactor, dividing the working periods of impaetor into three phases and establishing the computer emuiational model of percussive parameters. It draws a comparison between the results of model calenlation and experiment on the basis of analyzing the experiment results of impactor. The conclude provides credible foundation for designing and further ameliorating the impactor. 展开更多
关键词 PETROLEUM IMPACTOR percussion-rotary drilling MODEL
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冰下夺“冰”
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作者 WilliamC.Symonds HeidiDawley +1 位作者 陈少君 柏克 《商业周刊(中文版)》 1996年第7期50-51,共2页
在北美极少有象夸拉(Koala)地区那样偏僻遥远和令人生畏的地方,而加拿大西北地区BHP钻石有限公司的采矿营地就在夸拉。卡车只有在隆冬的3个月里才能开到那儿。从耶洛奈夫城开出,卡车要经过一些球冻的湖泊和475公里长的危险“球路”上... 在北美极少有象夸拉(Koala)地区那样偏僻遥远和令人生畏的地方,而加拿大西北地区BHP钻石有限公司的采矿营地就在夸拉。卡车只有在隆冬的3个月里才能开到那儿。从耶洛奈夫城开出,卡车要经过一些球冻的湖泊和475公里长的危险“球路”上的冻土带。由于风雪迷漫,般地剌目的白色反光让人辨不清方向,卡车常常是时走时停。加拿大西北地区行政长官唐·莫林说:“这里是加拿大最远的边界。” 展开更多
关键词 加拿大 钻石开采 夸拉工程 经济价值 产量 价格
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