Biosorption of Cr(VI) using low cost sorbents

Waste products from industrial operations, such as yohimbe bark, grape stalks, cork and olive stones were investigated for the removal of Cr(VI) from aqueous solutions. Equilibrium batch experiments at room temperature were performed. Metal uptake showed a pH-dependent profile and optimum uptake at initial pH between 2.0–3.0. Slight influence of NaCl on metal uptake was observed. The sorption data fitted well to the Langmuir model within the concentration range studied. Grape stalks proved to be the most efficient sorbent followed by yohimbe bark, cork and olive stones. N. Fiol is the recipient of the 2002 ACE Environmental Chemistry Award     

垃圾焚烧飞灰的石材化固化处理

为促进垃圾焚烧飞灰的无害化处理及资源化利用,提出了一种石材化固化处理方法,并对其产物的使用性能、毒物浸出特性及该方法的经济效益进行探索。结果表明:该处理方法利用C80PHC生产中高温、高压、高湿环境及磨细石英砂的存在使水泥水化产物转变为托贝莫来石,一方面提高混凝土的致密性及强度,减少毒物浸出通道;另一方面将毒物包容或固结在其石材化的晶格中,几乎杜绝了毒物浸出。同时其产物的脱模强度及高压蒸养强度均满足C80PHC的使用要求,从而确保了其资源化利用的可行性。石材化固化处理的处理成本仅约为108.1元/t,使用时也无需额外占用土地、增加设备和材料成本,因此有望在低成本条件下达到无害化处理的工艺水平,是一项经济、环保、可靠的创新技术。     

A preliminary study of the phycological degradation of natural stone masonry

For many years it has been realised that the weathering of stone is not merely determined by physical and chemical factors but also by biological agents. When the stone in question is a historic building or monument, the damage done constitutes an irretrievable loss of our heritage and history. Laboratory studies have commenced in Paisley to study the effect of photoautotrophs on the major sedimentary rock forming minerals, with a view to expanding this work to study the overall effect of these micro-organisms on heritage masonry. Tests were carried out on Albite, Calcite, Dolomite, Orthoclase, Siderite and Quartz, using axenic cultures of the following: Chlorella vulgaris, Chlorococcum tetrasporum, Scenedesmus obliquus, Oocystis marsonii, Stichococcus bacillaris. The rock chips were immersed in either water or bolds basal media and exposed to a mix of the micro-organisms listed above and then tested weekly for their pH, fortnightly for the waters chemical composition using inductively coupled plasma-atomic emission spectrometry (ICP-AES) and visually utilising the universitys SEM facilities. Work so far has revealed biologically mediated etching of minerals, a well-defined pH profile over a period of 90 days, as well as a variety of elemental release patterns for the different minerals.     

石材废水处理工程实例

介绍了石材废水集约化处理的一个成功实例,分析、总结了混凝沉淀法处理石材废水的可行性及注意事项,并通过比较得出石材废水集约化处理较分散治理具备明显优势的结论.     

废石粉渣制备混凝剂及其除浊净水效果研究

利用废石粉渣制备无机混凝剂,并研究所得初产品对硅藻土悬浮液和受污湖水样品进行处理的适宜操作条件以及除浊净水效果,结果表明,利用某些废石粉渣制备的混凝剂有较好效果,但制备工艺有待改善。     

拱形抗滑桩墙支护结构体系模型试验相似材料研制

根据模型试验相似比尺和桩土间应力协调要求,用机制砂、河砂、水泥、石粉等配置了40组(每组6个)低强度、低弹性模量的圆柱形微混凝土相似材料试件.测试结果表明:微混凝土具有和原型混凝土大致相同的应力应变阶段和破坏模式,可以模拟原型结构的力学行为和变形、破坏特征.砂率和石粉取代率不同时,微混凝土试件的轴压强度和弹性模量在较大...     

赣闽浙三省接合区砂金资源的分布与沉积学特点

赣闽浙三省接合区砂金资源分布广泛,尤以赣东北乐安江、昌江水系最富。本文是在对该区野外调查,取样分析和典型砂金矿床、矿点地质环境分析的基础上,认为冲积型砂金富集与矿源层分布,水系发育规模及地貌条件,含金物质搬运距离,水动力条件,沉积界面微地貌及合金物质沉积后埋藏状况有密切关系,掌握砂金沉积学特点有利于资源的勘探和开发。     

UNCERTAINTY OF EXTREME FLOOD ESTIMATES INCORPRATING HISTORICAL DATA1

ABSTRACT: The ability to predict extreme floods is an important part of the planning process for any water project for which failure will be very costly. The length of a gage record available for use in estimating extreme flows is generally much shorter than the recurrence interval of the desired flows, resulting in estimates having a high degree of uncertainty. Maximum likelihood estimators of the parameters of the three parameter lognormal (3PLN) distribution, which make use of historical data, are presented. A Monte Carlo study of extreme flows estimated from samples drawn from three hypothetical 3PLN populations showed that inclusion of historical flows with the gage record reduced the bias and variance of extreme flow estimates. Asymptotic theory approximations of parameter variances and covariances calculated using the second and mixed partial derivatives of the log likelihood function agreed well with Monte Carlo results. First order approximations of the standard deviations of the extreme flow estimates did not agree with the Monte Carlo results. An alternative method for calculating those standard deviations, the “asymptotic simulation” method, is described. The standard deviations calculated by asymptotic simulation agree well with the Monte Carlo results.     

环境哲学与历史性转变

所谓环境哲学，就是从哲学角度研究环境与发展这一矛盾的运动规律，并用以指导环境工作实践的一门科学。从哲学角度看，推行历史性转变首在转变那些不适应客观变化的观念、经验和制度，以实践作为检验真理的唯一标准，对受计划经济体制影响的理念和经验进行反思，走出误区，以利转变。环境与经济的“并重”和“同步”是促进环境与发展矛盾转化的根本途径，“综合”是用改革的方法解决发展中的环境问题，是实现前两个转变的基本保障。总之，实施“三个转变”就是发挥人的主观能动作用，积极创造条件，促使环境与发展的矛盾由“两难”向“双赢”转化，将“以牺牲环境换取经济增长”转变为“以保护环境，优化经济增长”，真正走上生产发展、生活富裕、生态良好的文明发展道路。