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991.
阐述了某钢铁厂冶炼炉渣堆放场中渣的放射性元素含量及照射量的规律性 ;铁合金厂钒铁冶炼贫渣的物理化学性质和矿物组成特性 ;并对它们作为水泥、肥料生产和筑路工程中的原材料及有用组分回收等方面的开发利用进行了探讨。  相似文献   
992.
 Permeability and its susceptibility to changes with time or exposure to chemicals are major factors in selection of earthen liners for use in hazardous liquid-waste containment systems. Earthen liners often consist of mixtures including both granular soil and fine matrix. Six different solid mixtures were tested to investigate the influence of hazardous liquid waste on their permeability. The granular part of the mixtures included sand and crushed natural zeolite, whereas the matrix was composed of bentonite and microcement. Highly acidic solutions, bases, leather industry leachate and municipal waste leachate were used as permeants. Of the mixtures tested, only two mixtures performed well against the attack of chemicals. The testing method was the falling head system with the compaction mold permeameter. The period of experiments varied from two to eight weeks. Received: 24 September 1998 · Accepted: 5 January 1999  相似文献   
993.
The kerogen of an organic-rich sample, termed f top, from the Gorodische section (Russian platform) was studied using a combination of microscopic, spectroscopic and pyrolytic methods so as to examine its chemical structure, source organisms and formation pathway(s). This kerogen, which is mainly composed of orange gel-like, nanoscopically amorphous organic matter, exhibits a relatively high aliphatic character; organic sulphur is mainly present as di(poly)sulphides and alkylsulphides. The f top kerogen was chiefly formed via intermolecular incorporation of sulphur in algal or cyanobacterial lipids and carbohydrates. However, its formation also involved oxidative condensation via ether linkages. Comparison of f top sample with other S-rich kerogens points to a closer similarity with Monterey kerogens rather than with a kerogen from the bituminous laminites of Orbagnoux.  相似文献   
994.
宗自华  陈亮  陈强  魏云杰  王锡勇  王驹 《岩土力学》2013,34(Z1):279-284
岩体工程质量是影响高放废物地质处置(HLW)工程长期稳定性和安全性的关键因素,也是处置库场址比选的重要依据。在地表岩体节理调查统计的基础上,采用RMR(relative metabolic rate)分级方案,探讨北山高放废物处置预选区内以花岗岩为主体围岩的岩体质量与岩体结构的对应特征,建立结构面间距D与RMR岩体质量总评分值之间的定量关系,对北山预选区芨芨槽地表岩体质量分布进行研究。研究结果表明,RMR与D值的点群分布具有扇形发散的正相关特征,随D值的增大,RMR亦呈增长趋势,但低级序岩体结构与岩体质量比高级序岩体表现出更好的对应关系。研究认为,选用RMR与D的点群中心线对应的线性方程评价花岗岩候选区的岩体质量可达到快速评价岩体质量、查明各级岩体空间分布特征的目的,同时也便于对不同候选场区进行大范围岩体质量对比。分析结果显示,北山芨芨槽预选地段BS16钻孔周边3 km2范围内主要以Ⅰ、Ⅱ级岩体为主,岩体质量总体较好且分布相对较为均匀。  相似文献   
995.
铁碳微电解-Fenton氧化处理海上废弃钻井液液相实验   总被引:1,自引:1,他引:0  
为处理海上油田废弃钻井液,以我国海上油田广泛使用的有机正电胶钻井液为例,研究采用铁碳微电解-Fenton氧化处理工艺可行性.结果表明,废弃有机正电胶钻井液及其固液分离后的废水COD超过废水排放标准.优化铁碳微电解-Fenton氧化的适宜条件:微电解时间不低于3h;双氧水质量分数为0.5%,氧化时间为2h.铁碳微电解-Fenton氧化处理工艺对废弃钻井液废液COD有较明显的处理效果,但一轮次处理无法达到排放标准.铁碳微电解-Fenton氧化—次氯酸钠深度氧化以及多轮次铁碳微电解-Fenton氧化处理可以使固液分离后的废弃钻井液达到工业污水排放二级标准.  相似文献   
996.
One of the most important problems arising from landfilling solid wastes is the leachate which contains high amount of pollution. Discharge of leachate without treatment causes negative effects on environmental and public health. In this study, parameters of chemical oxygen demand (COD), total nitrogen (TN), ammonia nitrogen (NH4‐N), and total phosphorus (TP) were examined in the samples taken from the influent and effluent of leachate treatment plant, where Odayeri landfill leachate is treated. Obtained results showed that the treatment plant, which consisted of preanoxic biological treatment system, ultrafiltration (UF) and nanofiltration (NF) units were operating with high efficiency. Among the examined parameters during study, COD, TN, NH4‐N, and TP were found to be treated at the rate of 99, 94.5, 99, and 93.8%, respectively. Landfilling is increasing rapidly in the world and this consequently brings the need of leachate treatment facilities. Therefore, this study is considered to be a guide for construction and operation stages of proposed new treatment plants.  相似文献   
997.
In the present study, the removal of Cu(II) was evaluated by raw and calcined phosphogypsum (PG) as an industrial product. The role of experimental factors on the removal of Cu(II) was examined by using D‐optimal and Taguchi designs. The experimental factors and their related levels were selected as initial pH of 3–6–8, adsorbent content of 5, 10, and 25 g L?1, contact time of 5, 10, and 20 min, and temperature of 20, 40, and 60°C. The results are evaluated by ANOVA test to extract important experimental factors and their levels. The performances of the suggested factorial designs were then compared and regression models that took into account the significant main and interaction effects were suggested. Taguchi design was found as a reliable solution with less number of experiments for adsorption studies with the optimized values. The resultant removal efficiency is calculated as 78.34%. The results revealed that calcined PG is an appropriate adsorbent for Cu(II) removal from leachate of industrial waste.  相似文献   
998.
人为地质作用刍议   总被引:5,自引:4,他引:1  
刘家仁 《贵州地质》2004,21(3):171-177
本文阐述了人为地质作用的概念及研究人为地质作用的意义、方法和任务,并就开展人为地质作用研究工作提出建议。以因果关系划分,人为地质作用可分为人力地质作用、人力诱发地质作用和人力诱导地质作用三类。人为地质作用具有作用速度快、强度大、范围广、效果明显、分布与人类活动场所相关、具有正负两方面效应、可人为重复、可控制等特点。研究人为地质作用是人类可持续发展的需要,是现代地质学发展的需要,是破除迷信、树立科学发展观的需要。研究人为地质作用在防灾、减灾、除灾,维护人类生存环境,利用地质作用规律借助大自然的力量造福人类,破除迷信等方面具有重要意义。人为地质作用研究要解决的是现在和将来的问题,大多数情况下不能再用“今天是过去的钥匙”。研究人为地质作用的发生过程、发展规律、作用后果和形成机制,研究人为地质作用的控制技术,研究人为矿床的开发利用技术,是人为地质作用研究的三大任务。本文建议:(1)加强人为地质作用研究力量,从深度和广度两个方面加强对人为地质作用的研究;(2)加强人为地质作用知识的普及。  相似文献   
999.
Food waste was collected from local hotels and fish feed pellets were produced for a 6 months long field feeding trial. Three types of fish feed pellets (control diet: Jinfeng® 613 formulated feed, contains mainly fish meal, plant product and fish oil; Diet A: food waste based diet without meat and 53% cereal; Diet B: food waste based diet with 25% meat and 28% cereal) were used in polyculture fish ponds to investigate the growth of fish (grass carp, bighead and mud carp), changes in water quality and plankton density. No significant differences in the levels of nitrogen and phosphorous compounds of water body were observed between 3 fish ponds after the half-year feeding trial, while pond receiving Diet A had the highest density of plankton. The food waste combination of Diet B seems to be a better formulation in terms of the overall performance on fish growth.  相似文献   
1000.
构造活动性是核废处置场评价的一项基本判别要素。文中通过对东天山阿齐山—雅满苏地区磷灰石裂变径迹测年及 构造隆升剥蚀过程的模拟来评价核废处置场的构造活动性。结果表明阿齐山—雅满苏地区样品磷灰石裂变径迹年龄集中分 布在81.7~51.4 Ma之间,反映出东天山地区晚白垩世—始新世存在一次明显的构造冷却事件,这与天山地区晚白垩世的抬 升剥露事件相一致。磷灰石裂变径迹长度介于13.60±0.11~14.36±0.10 μm之间,其长度标准差为0.98~1.22 μm,显示该区 磷灰石径迹形成后没有发生过明显的退火作用。根据地温梯度计算得到晚白垩世—始新世东天山阿齐山—雅满苏地区隆升 剥蚀速率为270~580 m/Ma。现有地质资料及热史模拟结果表明,东天山阿齐山—雅满苏地区在晚白垩世—始新世(84~49 Ma)期间经历了强烈的构造隆升—剥露事件,自始新世以后50 Ma以来,地壳处于稳定状态,新生代构造活动不明显,其 活动强度明显有别于天山其他地段。东天山阿齐山—雅满苏地区现在的构造地貌基本继承了晚白垩世的特征,处于构造活 动平稳期,符合核废处置场选址的构造要求。  相似文献   
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