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231.
陈若莉 《徐州工程学院学报》2010,(4):53-57
在粉煤灰理化特性分析的基础上,对粉煤灰进行了物理激发和化学激发.研究结果表明:物理激发和化学激发均能提高粉煤灰的吸附活性.化学激发方法在反应温度为90℃、反应时间为12h、灰钙比为5、水固比为15时,粉煤灰的吸附活性提高最大. 相似文献
232.
磁西勘查区主采煤层煤层气赋存特征 总被引:3,自引:2,他引:1
据勘探研究磁西勘查区主采煤层既是煤层气源岩,又是其储集层,煤层有机显微组分以镜质组为主,煤的变质程度为中~高变质的烟煤~无烟煤,生气量较高,为高瓦斯矿区。本区以正断层为主,断层使煤层与泥质岩层接触,具有一定的封闭性。煤层埋深较大,主采2号煤层直接顶板为泥岩、粉砂岩,岩性致密,透气性较差,有利于煤层气资源的保存,从而使煤层气含量升高。 相似文献
233.
JIANG YuXuan LI Zheng SUN YongJian YU TongJun CHEN ZhiZhong ZHANG GuoYi ZHANG GuangChen & FENG ShiWei State Key Laboratory of Artificial Microstructure Mesoscopic Physics School of Physics Peking University Beijing China School of Electronic Information & Control Engineering Beijing University of Technology Beijing 《中国科学:信息科学(英文版)》2010,(2)
We presented the analysis of the incomplete conduction in bonding medium in high power GaN-based light-emitting diode (LED) packages. A numerical study was carried out with parametric model to understand the junction temperature variation due to bonding medium defects. Transient thermal measurement was performed to evaluate LED’s junction temperature. Thermal resistance from chip to lead frame was 20 K/W in our sample LED. It was suggested that only 60% of the surface area of the bonding medium was involved... 相似文献
234.
235.
高密度电阻率法在采空区探测中的应用 总被引:1,自引:0,他引:1
简述了高密度电阻率法的基本原理和资料解释分析的方法.高密度电阻率法是一种具有成本低、效率高、采集信息丰富并且探测精度高的地球物理探测技术.采用高密度电阻率法,结合全站仪测量空间坐标数据进行地形校正,针对采空区的复杂状况,选用不同的极距,在复杂的采空区地表布设了5条测线,完成了3 679个测点的测量.结合测区地质状况和异常的特殊形态,通过数据处理,确定了采空区的分布位置,取得了良好的探测效果,证明了高密度电阻率法在当今工程地质勘察中具有很大的优势. 相似文献
236.
Based on engineering tests in the Huainan coal mining area,we studied alternative well location to improve the performance of surface wells for remote pressure relief of coalbed methane in mining areas.The key factors,affecting location and well gas production were analyzed by simulation tests for similar material.The exploitation results indicate that wells located in various positions on panels could achieve relatively better gas production in regions with thin Cenozoic layers,low mining heights and slow rate of longwall advancement,but their periods of gas production lasted less than 230 days,as opposed to wells in regions with thick Cenozoic layers,greater mining heights and fast rates of Iongwall advancement.Wells near panel margins achieved relatively better gas production and lasted longer than centerline wells.The rules of development of mining fractures in strata over panels control gas production of surface wells.Mining fractures located in areas determined by lines of compaction and the effect of mining are well developed and can be maintained for long periods of time.Placing the well at the end of panels and on the updip return airway side of panels,determined by lines of compaction and the effect of mining,would result in surface wells for remote pressure relief CBM obtaining their longest gas production periods and highest cumulative gas production. 相似文献
237.
The time-temperature-transformation (TTT) curve of the 00Cr25Ni7Mo4N duplex stainless steel was obtained with a Formastot-digital thermal dilatometer,and the influence of isothermal aging on σ precipitation was studied by metallographic observation,X-ray diffraction (XRD),and transmission electron microscopy (TEM).The results show that the decomposition of ferrite phase is accompanied by the formation of σ phase at 750-1000℃,especially in the range of 800-900℃.The longer the aging time,the higher the amount of σ precipitation.The area fraction of various phases remains at a certain value upon the completion of ferrite deformation.The temperature of 850℃ is the most sensitive transaction temperature,the incubation time for the formation of o precipitation is less than 1 min,and aging for 20 min leads to the complete transformation of ferrite.The o phase is formed preferentially at the α/α/γ junction,and then grows along the α/α boundary in the matrix. 相似文献
238.
广西大瑶山地区金矿的成矿构造类型可分为两大类:一类为流体型成矿构造,另一类为构造型成矿构造。其中:流体型成矿构造有流体脉型、流体角砾岩型及流体细脉型;构造型成矿构造有构造蚀变岩型、构造脉型。构造解析后认为:桃花金矿床的控矿构造(指控制成矿构造的构造)为伸展型脆-韧性剪切带,早期成矿构造类型主要为流体脉型,晚期为构造蚀变岩型;古袍志隆金矿床的控矿构造为逆-平型脆-韧性剪切带,早期成矿构造类型为流体细脉型、流体脉型,晚期为构造蚀变岩型;古袍湾岛金矿床的控矿构造为发育于顺层侵位花岗斑岩中的脆性破裂带,早期成矿构造类型为流体细脉型,属雏形成矿构造(控制特富金矿包),晚期为构造蚀变岩型;龙水金矿床的控矿构造为走滑型脆-韧性剪切带,其成矿构造类型为流体脉型;六岑金矿床的控矿构造为与隐伏酸性岩体侵位有关的节理-断裂型脆性破裂构造,其成矿构造类型为构造脉型及构造蚀变岩型。基于对该区金矿床成矿构造类型的划分及控矿构造类型的研究,本文对广西大瑶山地区主要金矿床(点)的成矿前景作出了评估。 相似文献
239.
In order to study the movement characteristics of groundwater in a deep mining area and solve the dispute of the distri-bution rule of hydro-chemical zoning which is contradicted by lixiviation water zoning in a horizontal direction, we directed our attention to the source of deep groundwater, its seepage and hydro-chemical characteristics in a typical mining area. We used a neotectonic water-control theory, chemical and isotope methods, as well as a method for analyzing dynamic groundwater conditions. The results indicate that 1) Karst water in the deep and medium parts of this mining area is recharged by vertical leakage through neotectonic fractures rather than seepage along strata from subcrop parts or surrounding flows; 2) from surface to deep leakage paths, the variation in the types of chemical groundwater agrees with the normal lixiviation water distribution rule and the age of mixed groundwater increases; 3) the water-rich zones along neotectonic fractures correspond with water-diluted zones in a hori-zontal direction; 4) the leakage coefficient and water capacity of aquifers increases during the flow process of Kant water along the antidip direction (from west to east) and 5) Karst water in shallow mining areas forms a strong runoff belt along strikes and quickly dilutes the water from deep and medium mining areas. Overall, chemical and dynamic water characteristics actually agree with in terms of the entire consideration for differences in vertical leakage and abnormalities in the zone of water chemical distribution, along a horizontal runoff direction. 相似文献
240.
针对滦下灌区设备老化、管理落后的问题,按照经济实用、运行稳定、技术先进、随时升级的原则,对滦下灌区管理处进行了灌区信息化建设.灌区信息化系统主要包括自动化采集、自动化控制、智能化调度3大功能,初步实现了自动采集数据、遥控启闭闸门、远程屏幕监控、智能磁卡收费等功能.该灌区管理系统自应用以来成效明显,可为我国其他灌区自动化改造借鉴. 相似文献