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991.
The nanometer MnO2 has outstanding electrochemical performance theoretically, but it is not suitable for actual utilization, which may result in capacity decrease and resource waste. In this study we have utilized the characterizations of the nanometer material, synthesized a type of nanometer α-MnO2 through KMnO4 and KNO3 with hydrothermal method, and mixed the products into micron electrolytic manganese dioxide (EMD) to enhance the electrochemical performance of the electrode.The cyclic voltammogram and galvanostatical discharge measurements of the samples were investigated. It is found that the 50﹪ nanometer MnO2 mixed electrode has the best electrochemical performance. The electrochemical performance improvement mechanism of the sample nanometer MnO2 mixed into micron EMD was discussed. With the existence of electrolyte, the nanometer MnO2 particles filled into the interspaces of the micron EMD particles, the mass and charge transfer conditions of the electrode reaction were improved, and the electrode polarization was diminished. 相似文献
992.
陇龙地区的地形特征一是冲沟纵横交错,沟壁陡立;二是黄土层厚度大,潜水位深。该区地震勘探具有地震波衰减快、干扰波强、信噪比低、施工困难等特点。通过实验,在该区不同地形条件下使用不同激发方式,并采用弯线观测系统及大偏移距,有效提高了地震资料的S/N和分辨率,使野外地震记录达到了地震地质解释的要求。 相似文献
993.
在煤田测井中,井径的变化对其它测井参数是一种干扰,但利用井径的相对变化值(井径扩大系数),可有效地评估岩石的强度等级和可采煤层顶底板的稳定性。统计鱼卡煤田东部勘探区29个钻孔孔径的变化值,按岩石抗压强度划分原则,将其七煤顶板稳定性划分为5个等级,据此固定了该煤田七煤顶板稳定性分布图。 相似文献
994.
REE geochemical characteristics of the No. 302 uranium deposit in northern Guangdong, South China 总被引:1,自引:0,他引:1
ZHANG Guoquan HU Ruizhong BI Xianwu FENG Haisheng SHANG Pengqiang TIAN Jianji 《中国地球化学学报》2007,26(4):425-433
The No. 302 uranium deposit, located in Guangdong Province, is a typical granite-type uranium ore deposit REE geochemical characteristics of the wall rocks, pitchblende, altered rocks, calcite and fluorite from this deposit have been systematically studied in this paper. The result showed that the alkali-metasomatic granites and other altered rocks have the same REE distribution patterns as Indosinian granites. It is indicated that the hydrothermal ore-forming solution had altered the Indosinian granites, and ore-forming materials may directly originate from the Indosinian granites. Calcite and fluorite of different stages are the products derived from the same source but different stages. The evolution and degassing of the mineralizing solution might induce LREE enrichment to varying degree. Mantle fluid and a large volume of mineralizer may be the crucial factors controlling uranium mineralization, and the hydrothermal solution with mineralizer played an important role in U transport and concentration. Meanwhile, the degassing of CO2 might promote U and REE precipitation. 相似文献
995.
996.
阐述了一种WebGIS的研究思想和实现方法。通过运用C++Builder开发GIS地图服务器、运用矢量标记语言(VML)结合ASP.NET实现GIS浏览器、运用JavaServlet结合Socket通讯技术解决GIS地图服务器和GIS浏览器之间信息传递,采用自定义XML作为数据交换语言,从而自主实现了WebGIS的全过程,此实现方式可用于GIS数据和其他图形数据的发布,不受限于任何商业GIS平台,具备WebGIS平台的雏形。此实现方法可以解决海量空间数据发布、图形编辑等当前WebGIS难点技术,并利用该方法成功实现了沈阳市突发性环境污染应急监测系统和辽宁省l:10000土地利用现状库的Web发布。 相似文献
997.
Tian Qinjian 《中国地震研究》2007,21(1):74-84
The interaction zone between southern Tianshan and northern Tarim is located at the northeast side of Pamir. It is a region with high seismicity. We constructed a seismotectonic model for the west part of this zone from geological profiles, deep crust seismic detection and earthquake focal mechanisms data. Based on the synthesized geological features, deep crust structure, and earthquake focal mechanisms, we think that the main regional tectonic feature is that the Tianshan tecto-lithostratigraphic unit overthrusts on the Tarim block. The Tianshan tectonic system includes the Maidan fault and thrust sheets in front of the fault; The Tarim tectonic system includes the underground northern Tarim margin fault, conjugate faults in basement and overthrust fault in shallow. The northern Tarim margin fault is a high angle fault deep in the Tarim crust, adjusting different trending deformation between Tianshan and Tarim. It is a major active fault that can generate large earthquakes. The other faults, such as the Tianshan overthrust system and the Tarim basement faults in this area may generate moderately strong earthquakes with different styles. 相似文献
998.
999.
Starting with the research status of bio-metallogenesis of TI deposits and their geology, this work deals with the geological
background of TI enrichment and mineralization and the mechanism of bio-metallogenesis of TI deposits, as exemplified by TI
deposits in the low-temperature minerogenetic province. This research on the bio-metallogenesis of TI deposits is focused
on the correlations between bio-enrichment and TI, the enrichment of TI in micro-paleo-animals in rocks and ores, bio-fossil
casts in TI-rich ores, the involvement of bio-sulfur in minerogenesis and the enrichment of bio-genetic organic carbon in
TI ores. Thallium deposits have experienced two ore-forming stages: syngenetic bio-enrichment and epigenetic hydrothermal
reworking (or transformation). Owing to the intense epigenetic hydrothermal reworking, almost no bio-residues remain in syngenetically
bio-enriched TI ores, thereby the TI deposits display the characteristics of hydrothermally reoworked deposits.
Supported by the National Natural Science Foundation of China (Grant No. 40372047) 相似文献
1000.