轿车覆盖件表面瘪塘的分类及其特点

瘪塘是轿车覆盖件的主要表面缺陷之一,其产生原因涉及覆盖件结构、模具、工艺参数等诸多方面。对瘪塘进行了较为详细的描述,并根据瘪塘产生部位的特征对其进行了分类,研究了各类瘪塘的特点,为产生机理和整改方法的研究奠定了基础。     

Finding all optimal solutions to the reserve site selection problem: formulation and computational analysis

The problem of selecting nature reserves has received increased attention in the literature during the past decade, and a variety of approaches have been promoted for selecting those sites to include in a reserve network. One set of techniques employs heuristic algorithms and thus provides possibly sub-optimal solutions. Another set of models and accompanying algorithms uses an integer programming formulation of the problem, resulting in an optimization problem known as the Maximal Covering Problem, or MCP. Solution of the MCP provides an optimal solution to the reserve site selection problem, and while various algorithms can be employed for solving the MCP they all suffer from the disadvantage of providing a single optimal solution dictating the selection of areas for conservation. In order to provide complete information to decision makers, the determination of all alternate optimal solutions is necessary. This paper explores two procedures for finding all such solutions. We describe the formulation and motivation of each method. A computational analysis on a data set describing native terrestrial vertebrates in the state of Oregon illustrates the effectiveness of each approach.     

用压实法防止煤矸石山自燃

本文分析了阳泉矿务局煤矸石山自燃的原因及几种灭火方法的适应性，介绍了碾压复盖法灭火技术在二矿矸石山取得成功的实例及分层压实法排矸工艺在五矿矸石山成功实施的实例，并认为煤矸石的资源化更为重要，更有前景。     

EFFECTIVENESS OF DUPONT TYPAR SHEETING IN CONTROLLING MACROPHYTE REGROWTH AFTER OVERWINTER DRAWDOWN1

ABSTRACT: A new polypropylene sheeting compound, DuPont Typar 3201 and 3301, was applied to the sediments of Country Lake (Portage Co., Ohio) in March 1978 after an overwinter drawdown, and regrowth of rooted macrophytes was compared to an adjacent control area in summer 1978. Regrowth was slight, and macrophyte biomass was at least 100X less than in controls. The sheeting material was permeable to gases and did not “balloon.” This material is recommended for use around docks, swimming areas, and boat mooring sites. Cost in 1978 was about $0.24/m².     

用突变理论分析矿山冒落型地震机理

矿山冒落型地震是一种破坏性最为严重的地质灾害之一。研究其成因机理 ,对矿山安全生产具有重大的现实意义。笔者根据矿山冒落型地震的特征 ,应用突变理论和能量守恒原理 ,建立了一个简单的力学模型 ,提出由地下开采引起采空区顶板突然破坏和冒落—释放能量—诱发地震的观点 ,并结合现场实例进行分析 ,得到顶板冒落和所释放出来的能量表达式 ,这为研究矿山冒落型地震成因机理提供了一种新的方法。     

冒落型矿震成因机理的研究

冒落型矿震属于塌陷地震的范畴 ,其形成和演化受到区内自然因素和人为因素的作用。笔者研究了顶板冒落的前兆特征、发展过程、运动形式和致崩原因 ,探讨了冒落型矿震的成因机理 ,提出了由于地下开采引起采空区顶板冒落 ,释放能量 ,诱发矿震的观点。     

Assessment of Dust Generation Due to Opencast Coal Mining– An Indian Case Study

Every mine in India has to obtain environmental clearance fromthe Govt. Air pollution is one of the most important parametersto be considered in preparing an EIA. However, there is no welldefined method for predicting thr air pollution impact due tomining. Increasing trend of opencast (O/C) mining leads toproduction of huge quantities of dust. Emission factor data havebeen utilised to quantify the generation of dust. The projectunder study is one of the largest opencast project (OCP) forcoking coal. The main sources of air pollution have beenidentified. The rate of emission per unit of a given activityknown as an emission factor has been utilised, taking localfactors into account. It has been estimated that due to topsoilremoval, overburden (O/B) removal, extraction of coal, sizereduction generated 7.8 t of dust per day. Wind erosiongenerated 1.6 t of dust per day and the whole operationproduced dust which accounted for 9.4 mt/day. They cause airpollution in the work zone and surrouding locations. Themethodology adopted may be used to quantify generation for otherprojects also.     

自燃煤矸石山覆盖材料压缩及压实特性实验

自燃煤矸石山表面构建覆盖层,需要具备一定的低渗透性能以有效阻隔空气,防止煤矸石山内部发生自燃。本研究通过室内实验,测定煤矸石山构建覆盖层涉及的碾压材料包括黄土、粉煤灰及掺有粉煤灰的混合土样的界限含水率、一维压缩特性及压实特性,揭示和分析7种覆盖材料配方的压缩压实特性,表明覆盖材料通过碾压可有效阻隔空气,起到阻燃作用;将粉煤灰掺人到一般黄土材料中,可减缓混合土样击实曲线的陡峭性,从而降低材料在碾压中对含水率的敏感度。实验旨在为进行煤矸石山覆盖层碾压提供科学的实验数据及设计参数。     

污泥膜覆盖好氧发酵通风调节方法

建立了污泥膜覆盖好氧发酵通风实验装置。结合污泥不同发酵阶段通风量的需求,分别通过风机入口节流调节和变频调节实现实验堆体系统通风量的改变,测取了相应的堆体风压和风机功率;结果表明,2种调节方式均适用于膜覆盖好氧发酵工艺,但变频调节在调节性能上优于节流调节。而且,变频调节的风机能耗远小于节流调节,在小风量通风时相差可达5～6倍。由于功能膜的作用,变频调节的通风量近似为频率的二次函数而非理论上的线性关系。     

PM2.5及其工业源头控制技术

PM2.5对人体健康和空气质量有巨大的危害,环保部已修订相关法规和文件,将PM2.5纳入我国环境空气质量监测范围,采取有效手段控制PM2.5是我国一项重要的环保目标,在工业企业中采用最先进的表面过滤技术可从源头控制工业PM2.5的排放。