浮选药剂对铅锌尾矿中重金属微生物溶出的影响

以青海某铅锌尾矿为研究对象,采用静态试验模拟研究了4种浮选药剂对尾矿在嗜酸氧化亚铁硫杆菌协同作用下重金属铅锌溶出的影响.结果发现,除丁胺黑药外,与未添加药剂相比,随溶出时间延长,其他3种黄药的存在均导致溶出体系的氧化还原电位升高而p H值降低,影响顺序均为异丁基黄药乙基黄药≈戊基黄药丁胺黑药.黄药体系Pb、Zn累积溶出量远大于黑药体系且Zn更易溶.50d时,Pb、Zn最大溶出浓度分别为77.60、167.00mg/L,其中异丁基黄药最有利于重金属铅锌的溶出.原电池效应、Cu2+对闪锌矿的活化以及浮选药剂的水解能力差异是导致不同浮选药剂对重金属溶出差异的主要原因.尾矿残渣XRD分析表明不同浮选药剂存在体系溶出过程中生成的新物质含量有所差异.     

ILO职业安全卫生标准体系现状综述

为了解国际组织职业安全健康标准状况,收集了国际劳工组织职业安全卫生标准有关资料,对国际劳工组织职业安全卫生标准进行了梳理,按照标准属性、适用对象和范围,对标准进行了分类归纳,梳理形成了国际劳工组织职业安全卫生标准体系的整体框架,并对标准体系构成要素的主要内容作了简要的阐述,总结了国际劳工组织职业安全卫生标准及标准体系的特点。     

螺旋隧道火灾特性小尺寸实验研究

为探明螺旋隧道火灾特性,防止人员高温伤害,基于Froude准则,搭建比例1∶67的小尺寸螺旋隧道实验模型,采用模型实验方法研究不同坡度和不同风速下螺旋隧道火灾温度分布规律及烟气蔓延特性。研究结果表明:低坡度条件下,螺旋隧道内高温区以火源为中点呈对称分布状态;随着坡度的增加,隧道内高温区逐渐向下游延伸,火源处拱顶下方温度呈现先增大后降低再升高的变化规律;无论是自然风还是机械纵向通风,新鲜冷空气的吹入对隧道温度的降低起到主导作用,且风速越大,温降幅度越大;随着隧道坡度和自然风速的增加,火羽流由竖直狭长型转变为燃烧不稳定的大截面火焰,同时坡度增加抑制了火灾烟气逆流,促进了烟气向火源下游的蔓延速度,大大提高了排烟的有效性,减少人员伤害。     

复杂难采高瓦斯煤层简易放顶煤开采综合防灭火技术研究

笔者在分析淮南矿区复杂难采高瓦斯煤层简易放顶煤开采工作面自然发火时空特点基础上 ,提出建立一套预测、预报、预防和充分准备灭火的防灭火体系 ,并阐述了预测、预报、预防的实施方法。该方法应用于淮南矿区 ,成功地开采了数个简易放顶煤工作面 ,综合防灭火技术取得了较好经济和社会效益。     

实用修辞与课堂教学

文章分析了"实用修辞课"的教学现状,关键在于观念的转变、认识到位。对"实用修辞课"教学的认识定位要从"可有可无"转向"大有可用";针对大学实用汉语修辞课的教学目的、内容和方法提出了理论和实用的依据。     

减小浅埋暗挖法施工对建构筑物影响的措施

地铁隧道施工过程中,由于施工产生扰动,必然会破坏岩土体原有的应力平衡状态,从而产生一系列与岩土工程环境有关的问题,如土层位移以及由此产生的地面建筑物、地下管线及桩基等建构筑物的破坏等。在城市环境条件下的第四纪地层中进行浅埋暗挖,更加严格要求土层位移必须控制在允许范围之内,以达到环境土工的安全使用。笔者重点针对地层沉降的组成及控制建筑物受开挖产生的影响,总结实践经验,给出了控制开挖产生沉降的多种方法,同时提出隔离措施,具有一定的使用价值和工程施工指导意义。     

海上溢油回收技术研究

论述了厌氧-好氧(A/O)工艺的基本原理及工艺参数。该工艺在冀东油田两座废水处理站的应用结果表明,对废水中石油类物质、COD、硫化物去除效果明显。高一联合站及柳一联合站污水经处理后,石油类物质去除率分别为90.6%和96.0%;COD去除率分别为86.0%和91.6%;硫化物去除率分别为94.8%和98.2%,处理后的污水均达到一级排放标准。另外,采用厌氧-好氧工艺的成本相对较低,处理费用低于0.5元/m3。处理后的污水若回注地下,平均费用为4.7元/m3。     

A LAW AND ECONOMICS APPROACH TO RESOLVING RESERVOIR SEDIMENT MANAGEMENT CONFLICTS1

The loss of the world's reservoir capacity to sedimentation can be mitigated by altering dam operations to release sediment downstream. However, legal uncertainty regarding whether dam owners are liable for damages to surrounding landowners due to altered operations provides a significant disincentive for sustainable sediment management. Past work recommends that courts apply a “rule of reasonableness” in assessing liability: dam owners should be held liable for damages only if they act unreasonably in altering operations, and surrounding landowners should take reasonable measures to mitigate foreseeable damage. Based on past cases, judicial determinations of reasonable reservoir management and reasonable precautionary measures by landowners are generally highly speculative, controversial, and based on limited information. Courts can ease the future burden of making these difficult determinations with rulings that create economic incentives for parties to act reasonably. For example, courts might entitle landowners to be free from sediment related damages, and protect the entitlement with a liability rule. This gives dam owners an economic incentive to release sediment only if the benefits of doing so outweigh court ordered damages to landowners. Past judicial decisions are largely consistent with this legal regime.     

SURFACE AREA CORRECTIONS APPLIED TO A RESOURCE MAP1

ABSTRACT: Generally a difference exists between the horizontal planar area of a watershed as measured on a map and the actual surface area. A technique is presented, utilizing a topographic map, for computing the difference in the two areas as well as yielding a prediction of the actual surface area. Spatial variations in the magnitude of the difference in the two areas for small local sites over the watershed are displayed on computer generated maps. The technique is also used to adjust various inventory variables on maps, such as vegetation density, to reflect actual surface coverage. This allows estimates to be made of the difference in using corrected versus uncorrected area related parameters in mathematical functions describing processes occurring in the atmosphere-surface boundary layer.     

THE RELATIVE INFLUENCE OF DAMS AND SECULAR CLIMATIC CHANGE ON DOWNSTREAM FLOODING,AUSTRALIA1

An examination of 100 years of flood record at Windsor on the Hawkesbury River in Eastern Australia suggests that Warragamba Dam, which encloses 62 percent of the catchment area, has negligible effect upon flooding. Secular climate change is the important variable in determining changes in flood regime.