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141.
142.
Deformation Mechanism and Stability of a Rocky Slope 总被引:1,自引:1,他引:1
A high slope is located on the side of the spillway at a hydropower station in Southwest China, which has some weak inter-layers inclining outwards. Parts of the slope show heavy weathering and unloading. There appeared deformation and tensile crack either on the surface or on the afteredge of the slope during excavation, and under a platform (elev. 488 m), two levels of slopes collapsed on the downriver side. Based on the investigation in situ and the analysis of the geological structure, the conceptual model of deformation and failure mechanism was erected for this slope. Furthermore, the deformation characteristics were studied with FLAC^3D numerical simulation. Comprehensive analysis shows that the whole deformation of the slope is unloading rebound in certain depth scope and the whole body does not slide along any weak interlayer. In addition, two parts with prominent local deformation in the shallow layer of the slope show the models of "creep sfiding-tensile cracking" and "slidlng-tensile cracking", respectively. Based on the above analysis, the corresponding project of support and reinforcement is proposed to make the slope more stable. 相似文献
143.
W. J. Zhang M. Zhang F. Xiao L. P. Fang D. S. Wang 《International Journal of Environmental Science and Technology》2014,11(3):731-738
Pretreatment of waste emulsions with high organic content by a combined process of vibratory shear enhanced process and Fenton’s oxidation prior to biological treatment was investigated. Vibrating membrane had shown good performance in chemical oxygen demand and oil removals and the mitigation of concentration polarization. However, the permeate after filtration processing still contained high content of organics. Thus, additional Fenton oxidation was applied to reduce the organic loading, and improve the biodegradability of the wastewater. The optimal molar ratio of ferrous iron to hydrogen peroxide was 0.05 obtained from the jar-test experiments. Removal of organics was enhanced by increasing hydrogen peroxide dosage, while efficiency of hydrogen peroxide reached maximum of 1.11(w/w) at the hydrogen peroxide dosage of 6.8 g/L. Furthermore, the biological experiments indicated that the high concentration of organics could inhibit microbial activity, which decreased the chemical oxygen demand degradation rates. The adaptive period of the microbe was greatly shortened using Fenton’s reagent at the low dosages. The improvement of the biodegradability could be explained by partial mineralization and chemical transformation of parent organic compounds after Fenton oxidation. 相似文献
144.
研究了新显色剂 5 -(4-溴苯偶氮 ) -8-羟基喹啉 (BAHQ)与钴 (Ⅱ )形成配合物的条件。试验表明 ,该显色剂的离解常数pKa1 ,pKa2 分别为 1.80 ,7.90。BAHQ与钴 (Ⅱ )形成配合物的最大吸收峰在 483nm处。钴 (Ⅱ )浓度在 0~ 16 μg/ 2 5mL范围内符合比耳定律 ,表观摩尔吸光系数ε483 =5 .10× 10 4L·mol- 1 ·cm- 1 ,对比度△λ =88nm。考查了二十多种离子的干扰情况 ,用于测定维生素B1 2 药品中的钴 ,结果满意 相似文献
145.
Rare—Earth Element Geochemistry of Elogites from the Ultra—High Pressure Metamorphic Belt in Central China 总被引:1,自引:1,他引:1
Based on their REE contents and REE patterns,eclogites from the ultra-high pressure metamorphic belt in central China may be roughly divided into xis types including LREE-rich.LREE-rich positive Eu anomaly,LREE-rich negative Eu anomaly,REE pattern-smooth,MREE-rich and HREE-rich.The LREE_rich,LREE-rich positive Eu anomaly and LREE-rich negative Eu anomaly types of eclogites are dominant .REE types of eclogites in different areas can be compared and the REE feactures of the same REE type of eclogites in different areas are similar.The results of reconstruction of the primary rocks show that the primary rocks of eclogites possibly are dominated by continental tholeiites which are the product of partial melting of relatively fertile mantle and the rocks of tholeiite crystallization-differentiation.There is perfect evolution relationship among the primary rocks of the LREE-rich, LREE-rich positive Eu anomaly and LREE-rich negative Eu anomaly types of eclogites and among those of the REE pattern smooth and MREE-rich types of eclogites,the former three types were deried from continental settings and the latter two from nearly oceanic settings.Meanwhile,it is concluded that the mantle sources of primary rocks of the eclogites are inhomogeneous and the primary rocks of eclogites in this area appear to have undergone varying degree of crustal contamination. 相似文献
146.
东北大兴安岭东南处扎兰屯地区东南部分布着糜棱岩化花岗岩,1∶20万地质图依据其产状及岩石特征将此类变形花岗质岩石划分为混合变质岩系,视为额尔古纳-兴安地块早元古代形成的结晶基底。该区糜棱岩化花岗岩带位于大兴安岭与松辽盆地的过渡带上,呈小面积不连续带状出露。研究表明,该区牦牛沟岩体眼球状糜棱岩化花岗岩的钾长石-全岩Rb─Sr等时线年龄为(173±3.45)Ma,锶初始值为0.733 0±0.000 61,明显高于区域中侏罗世花岗岩的锶初始值(0.705~0.710),糜棱岩化花岗岩的原始结晶年龄可能为古生代。根据野外地质观察和定向标本显微观测,牦牛沟北东向韧性构造变形带具左行走滑性质,该期左行走滑变形时代的确定对大兴安岭地区中生代区域构造演化具有重要意义。 相似文献
147.
Nengping Shen Zhengwei Zhang Fuhua You Jiantang Peng Xiaoqing Zhu Jiafei Xiao 《中国地球化学学报》2012,31(4):362-375
The polymetallic(Pb,Zn,Cu,etc) ore belt on the southwestern margin of Tarim is one of the major regions with the greatest prospecting potential in Xinjiang.Reported in this paper are the lead isotope data for 66 sulfide samples(including 50 galena samples,15 chalcopyrite samples and 1 pyrite sample) collected from such representative deposits as Tamu,Tiekelike,Kalangu,Abalieke,etc.in this ore belt.The Pb isotopic ratios of 206 Pb/204 Pb,207 Pb/204 Pb and 208 Pb/204 Pb in the galena samples range from 17.931 to 18.176,15.609 to 15.818 and 38.197 to 38.944,with the average values of 18.017,15.684 and 38.462,respectively.Those in the chalcopyrite samples range from 17.926 to 18.144,15.598 to 15.628 and 38.171 to 38.583,with the average values of 18.020,15.606 and 38.262,respectively.The pyrite sample has the Pb isotopic ratios of 206 Pb/204 Pb,207 Pb/204 Pb and 208 Pb/204 Pb to be 17.980,15.604 and 38.145,respectively.In combination with the previous Pb isotope data for sulfides,it is found that there is only a slight variation in the Pb isotopic composition of galena,chalcopyrite,sphalerite and pyrite in the ore belt.However,there is some difference in Pb isotopic characteristics between galena and chalcopyrite,especially the Pb isotopic composition of galena shows an obvious linear correlation with some other relevant parameters(e.g.β and γ).The comprehensive analysis suggested that lead in galena(maybe including sphalerite and pyrite) was derived principally from wall rocks and underlying basement,and that in chalcopyrite only originated from the basement.The single-stage model ages of these sulfides couldn’t indicate the time limit of metallogenesis(Pb,Zn,Cu,etc.),and the positive linear correlations for the Pb isotopic composition of galena are of no single-stage and two-stage Pb-Pb isochron significance.Furthermore,there are significant differences in Pb isotopic composition characteristics between the genetic type of deposits in this polymetallic ore belt and the Mississippi Valley type(MVT).In addition,the authors also pointed out that there is a phenomenon of differentiation(not paragenesis) for lead and copper elements during the process of metallogenesis in this ore belt. 相似文献
148.
运用多学科、多手段相结合的方法,从区域构造稳定性、构造岩研究、构造裂隙统计分析、红外相位法位移监测,高密度电阻率法、钻探验证、年代学研究、新构造运动分析、遥感图像解译、地震安全性评价、数值模拟、工程地质条件分析等方面入手,对信阳市燃气混气站的断裂活动性和场地稳定性进行了全面而系统的论证;指出场区断裂规模小,第四纪无大规模差异升降运动,无活动断裂通过,邻区地震活动小且弱,区域构造稳定性高,应力平缓,工程地质条件良好,是一个稳定的“岛区”,井指出系统而全面的综合研究方法是研究工程稳定性项目行之有效的手段。 相似文献
149.
野外调查发现在靠近中蒙边界的额济纳旗霍布哈尔地区存在带状构造片岩,片理倾向南东,拉伸线理沿北东向,片岩内存在指示左行剪切的旋转碎斑系、不对称压力影等显微剪切组构。显微构造尺度上,片理结构由片理域与微片石组成,形成极易开裂的潜在破裂面。区内构造片岩是北东向韧性剪切带的组成部分,成因与韧性的剪切运动有关,经样品UY-1的LA-ICP-MS锆石U-Pb测年法测定,得到糜棱岩化的流纹斑岩年龄为286.3Ma±2.0Ma,后期侵入的闪长岩年龄为284.2Ma±2.4Ma,约束了构造片岩的形成时代为286.3Ma^284.2Ma(早二叠世)。结合区域地质资料,认为构造片岩带的形成与早二叠世阿尔金-东蒙古断裂的左行走滑剪切活动有关。 相似文献
150.