催化燃烧法处理炼油污水处理场臭气

介绍了污水处理场臭气来源、危害和影响，从技术、经济和环境效益等方面对几种处理方法进行了比较，提出了采用催化燃烧法的技术实施方案。     

基于人工神经网络的行业无害化生产能力评价模型研究

利用BP前向人工神经网络方法 ,建立了一种全新的基于人工神经网络的行业无害化生产能力评价模型 ,该模型采用动量梯度下降反向传播和学习速率自适应调整相结合的训练学习算法。最后 ,以造纸及纸制品业为例 ,对中国各省市造纸行业的无害化生产能力进行评价 ;并进一步分析中国各省造纸行业无害化生产能力的时空分布规律 ,为我国行业规划、布局决策提供科学依据。     

BP网络应用于大气环境监测点的优选

为了对大气环境监测点进行优化选择 ,以大气质量分级标准为训练样本 ,构造BP网络进行训练 ,用训练好的BP网络对某地的大气环境监测采样点进行了优选 ,并与物元分析法优选结果进行比较。结果表明 ,BP网络用于环境测点优选具有较好的客观性和应用性     

水质动态评价的马尔柯夫方法

根据随机过程原理 ,构造了一个新的概率转移矩阵 ,并在此基础上引入进步度的概念 ,对河流水质综合质量变化情况进行动态评价。最后给出了实例分析     

生化-砂滤-光催化氧化处理苎麻脱胶废水

根据苎麻脱胶废水的水质特点 ,选择了水解酸化 -接触氧化 -砂滤 -光催化氧化处理工艺 ,结果表明 ,出水水质达到了GB8978 1996二级排放标准 ,大部分指标达到了一级排放标准。该工艺具有针对性强、占地面积少、运行稳定、处理费用低、操作管理方便、无二次污染等优点 ,值得推广应用     

上海市扬尘污染源遥感解译及其管理信息系统

利用遥感影像资料,分析了上海市扬尘污染源的空间分布特征与规律,并计算了上海市主要扬尘源的起尘量。利用获取的基础数据,建立了上海市扬尘污染源管理地理信息系统,为上海市扬尘污染源的控制管理提供了依据。     

Toxic metals in sewage sludge-amended soils: has promotion of beneficial use discounted the risks?

Land application of contaminated waste products has been defended as beneficial use by some scientists and regulators, based on the premise that the behavior of any toxins accumulated in soils from this practice is reasonably well understood and will not have detrimental agronomic or environmental impacts into the foreseeable future. In this review, I use the case of toxic metals in sewage sludges applied to agricultural land to illustrate that metal behavior in soils and plant uptake is difficult to generalize because it is strongly dependent on the nature of the metal, sludge, soil properties and crop. Nevertheless, permitted agricultural loadings of toxic metals from sewage sludges are typically regulated using the sole criterion of total metal loading or concentrations in soils. Several critical generalizing assumptions about the behavior of sludge-borne metals in soil-crop systems, built into the US EPA risk assessment for metals, have tended to underestimate risks and are shown not to be well justified by published research. It is argued that, in the absence of a basic understanding of metal behavior in each specific situation, a more precautionary approach to toxic metal additions to soils is warranted.     

A survey of diagnostic amniocenteses in Oxford from 1974–1981

A survey was conducted of the results of mid-trimester diagnostic amniocenteses in the Oxford Region from 1974 to 1981. The survey used data relating to all 4357 singleton pregnancies in which an amniocentesis was performed during this period. Follow-up information on outcome was obtained in respect of 4284 (98 per cent) pregnancies. A cell culture to determine karyotype and an alpha-fetoprotein determination was carried out in all cases. From 1974 to 1981 amniocenteses became increasingly common, rising from 2 to 32 per 1000 births. The most common indication for amniocentesis was a high risk of a chromosome abnormality–56 per cent of all amniocenteses. Within this group advanced maternal age was responsible for 89 per cent of the cases. The next most common indication was a high risk of a neural tube defect (37 per cent of all amniocenteses)–in 1974 a raised maternal serum alpha-fetoprotein level accounted for only 4 per cent of these; by 1981 this had risen to 67 per cent. There were seven false-positive and 132 true-positive diagnoses of neural tube defect; since 1981, with the introduction of amniotic fluid acetylocholinesterase determination as a secondary diagnostic test for neural tube defects, there have been no further false-positive diagnoses. In 1981 76 per cent of women aged 35 years or more did not have an amniocentesis. It is not known to what extent this was due to not offering women in this age group amniocentesis or to women not accepting such an offer.     

机械强化污泥回流式一体化活性污泥法的运行机理研究

活性污泥通过机械搅拌强化污泥内循环回流,提高了污泥的活性,并且使污泥浓度可达到4.5kg/m3,用该机械强化污泥回流式一体化活性污泥法处理小区生活污水,当水力停留时间为3h,溶解氧为2.2mg/L,机械搅拌速度为250r/min时,CODcr、氨氮去除率均可达到83% 以上,出水达到国家污水排放一级标准.该一体化活性污泥法简单易行,运行成本低,投资小,操作维护方便,是生活小区生活污水适宜的处理工艺技术.     

沈阳张士污灌区土壤重金属元素形态分析

选取沈阳张士污灌区土攘样品,采用欧共体标准局的三步提取法研究土壤中5种重金属元素的形态分布.研究结果表明,在该污灌区土壤中,Cd和zn主要以B1(水溶态、可交换态与碳酸盐结合态)和B2(铁-锰氧化物结合态)为主,分别占总量的49.4%、26.4%和43.9%、44.3%.Cu、Pb主要以B2(铁-锰氧化物结合态)和B3(有机物与硫化物结合态)为主分别占总量的43.4%、66.6%和29.1%、25.3%.Cr以B3(有机物与硫化物结合态)和残渣态为主,分别占总量的40.4%和42.5%.元素总量和形态分析的结果表明该地区土壤污染为单一的镉污染土壤,且镉的可迁移性强,易被植物吸收.