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31.
电镀镍锰胎体金刚石钻头的应用   总被引:5,自引:1,他引:5       下载免费PDF全文
对电镀镍锰胎体金刚石钻头和镍钴胎体钻头的使用情况进行了对比。实践证明,镍锰胎体钻头特别适用于钻进坚硬破碎、强研磨性地层和软硬交替的地层。  相似文献   
32.
The quantity and quality changes of cropland in Jilin province are analyzed by combining the statistics from 1949 to 1999 and land-use maps interpreted from TM images in 1986 and in 2000. In general, the decreasing trend of the cropland in Jilin province was derived from the statistic data in 1949-1999. While since 1983, the cropland area has increased slightly, because of the conversion from other land-use types to cropland. It is showed that the net increase of cropland was about 43.40×104 ha. While the quality change of the cropland can be seen from that mainly caused by the conversion from forestland, grassland to cropland and the change mainly took place in the west, where it is ecologically fragile. According to the spatial distribution model, the centroids' move of the cropland and the grain production are calculated, whose directions are not consistent. The impact of the dynamic change of the cropland on food security is further analyzed.  相似文献   
33.
Most urban rivers play an important role in urban flood control and drainage in China, but pollution is fast becoming an issue of greater importance in water management. In this study, 63 zooplankton species were recorded in four downtown rivers in Shanghai between November 2007 and October 2008. Of these, 44 species belonged to the Rotifera, 13 to Cladocera, and six to Copepoda. The three most frequently occurring zooplankton (Brachionus calyciflorus, Microcyclops Ieuckarti, and Asplanchna priodonta) accounted for 80.00%, 76.84%, and 53.68%, respectively. Rotifera were found to be dominant, comprising 86.26% of total zooplankton, while cladoceran and copepod abundance amounted to 5.08% and 8.67%, respectively. Water temperature, salinity, electrical conductivity, and total nitrogen were of the greatest significance in the occurrence of zooplankton. Two species (Schmackeria forbesi and Lepadella ovalis) were notably more sensitive to environmental factors such as salinity and electrical conductivity than other species. The population size and community were inversely correlated with the increasing nutrient levels of the four rivers, suggesting that the water quality of the four rivers had been gradually recovering from a severe eutrophic state and that water conditions of the rivers had been gradually improved.  相似文献   
34.
阐述了基于地理国情普查数据与多时相航天遥感影像资料,对昌江县沿海地表覆盖变化进行监测,形成自1996年至今近20年昌江县沿海地表覆盖变化监测成果。同时,针对不同时期地表变化情况进行统计,分析了地表覆盖构成与转移,形成系列数据、图件、报告等成果,为建设管理沿海林地、保护沿海地带生态环境、合理利用开发海岸线等提供科学的决策依据。  相似文献   
35.
鄂尔多斯盆地西南部地表为巨厚黄土塬区,地表结构复杂,低降速带厚度变化快,沟中弯线受地形条件限制,测线成网困难,直测线采集资料信噪比和分辫率都较低,难以满足目前岩性勘探的需求。针对这种情况,在经过理论论证和生产试验后,研发了一套针对黄土塬地区的非纵地震勘探技术,这种技术兼顾吸收了黄土塬沟中弯线、黄土塬多线及三维地震勘探技术的优点,不仅避开了黄土塬近炮点强能量干扰,而且还展宽了叠加道集方位角。针对非纵地震资料特点,在保真保幅处理理念指导下,通过非纵资料处理技术攻关,提出了针对非纵资料的三维静校正技术、创新性应用三维噪声压制模块压制非纵测线相干噪声、改进了基于VSP测井合成记录的井控处理理念,形成了一套巨厚黄土塬区低信噪比非纵地震资料处理技术序列。  相似文献   
36.
新生界火山岩是泰国Phetchabun盆地Wichian Buri次盆的主要含油气岩系,但因火山岩喷发环境复杂,喷发期次频繁,造成火山岩岩性复杂,识别难度较大,岩相展布不清,这些因素严重制约着油气的进一步勘探和开发。通过岩心、岩石薄片、测井及地震等资料分析,总结了研究区火山岩的岩性特征,并提出相应的识别方法,同时对火山岩的发育期次和岩相展布进行了研究。结果表明:①研究区火山岩类型丰富,从基性岩至酸性岩、熔岩至火山角砾岩都有发育,以偏碱性玄武岩为主; ②自然伽马、密度及光电吸收界面指数测井对火山岩成分变化最为敏感,成像测井可以提供火成岩的结构和构造信息,两者结合可准确地识别火山岩岩性; ③结合测井和地震响应特征,研究区新生界火山岩为3期喷发的产物,可识别出火山通道相、溢流相、爆发相和火山沉积相等岩相类型,并预测其分布规律。研究成果为研究区火山岩的岩性识别提供了有效手段,并明确了岩相展布特征,可为研究区的油气勘探和开发提供一定的依据。  相似文献   
37.
The objective of this paper was to investigate a petroleum-contaminated groundwater site in northeast China. Based on the monitoring and analysis of environmental characteristics of groundwater slightly contaminated with petroleum, microbes were added into the petroleum-contaminated groundwater via single-well and multiple-well models to enhance bioremediation. The effect of enhanced bioremediation was monitored and analyzed, and variations in the environmental characteristics of groundwater containing total petroleum hydrocarbons (TPH) were identified to provide a scientific basis for controlling and remediating petroleum-contaminated groundwater. Findings confirmed that this site was slightly contaminated and TPH levels exhibited a slight decreasing trend. After enhanced remediation, the microbial degradation effect was large, and the TPH concentration significantly reduced. In particular, near the wells treated by bioremediation, the amounts of electron acceptors, such as NO3 ?, Fe3+, and SO4 2?, markedly decreased. The product of the microbial degradation process, HCO3 ?, gradually increased in the treated wells. Activities of the enzyme catechol 1, 2-dioxygenase decreased, while those of catalase increased. Reductions in pH, from 7.4 to 6.1, were recorded, and the groundwater environment became further deoxidized.  相似文献   
38.
某矿床为一大型的铜镍铂钯矿床,原矿石化学分析有用元素为:Pt1-38gtPd2-36gt、Cu0-14%、Ni0-22%。显微镜观察发现,矿石主要金属矿物为黄铜矿、紫硫镍矿、黄铁矿、磁铁矿、铬铁矿,脉石矿物为蛇纹石、辉石等。经显微镜观察以及电子探针扫描分析,铂钯矿物在矿石中嵌布颗粒粒度细小,与不同矿物连生,根据电子探针分析,仍有许多超显微状态的铂钯矿物赋存在硫化矿物中。1 样品制备与仪器设备及实验条件从原矿石中挑选部分有代表性矿石,切割抛光制成矿石光片,经显微镜镜下鉴定后,留待进行电子探针分…  相似文献   
39.
Considering that available data in Li32 block is limited, log phase method and core analysis were used to divide sedimentary facies and sequence, the former is principal, and two short-term cycles, five middle term cycles, and fifteen short-term cycles were divided. Combined seismic interpretation with fault point and fault rod, the instantaneous phase profile explained small fault more clearly and accurately. The sever faults were analyzed, and integrated structure was constructed. Lithofacies in cored wells were observed; the grain-size probability curves mainly are suspension and jumping transport; grain size is mainly for the siltstone and fine sandstone; the color of mud in the second segment of Shahejie formation (ES2) is mainly gray–green, gray to dark gray, these reflect that sediment environment is delta front, which included underwater distributary channel, mouth bar, distal bar, and so on. Well data and structural maps were integrated to build 3D structure model and sedimentary microfacies model of Li32 reservoirs using stochastic simulations with geometry data. The integrated 3D geological model is a valuable tool of reflecting geologic body with great reality and can accurately represent and describe the complex reservoir heterogeneity.  相似文献   
40.
伍超群 《岩矿测试》1994,13(1):45-48
文章简述了电子探针分析的原理,并以湖南宝山西铅锌银矿床为例在研究Pb,Zn,Ag的赋存状态的基础上,着重探讨了电子探针在矿物命名,矿物形貌特征和组成元素的赋存状态等工艺矿物学方面的应用。  相似文献   
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