活性氧化铝和活性氧化镁处理高氟饮用水的比较

针对相同的高氟饮用水水质,利用活性氧化铝和活性氧化镁两种吸附剂进行了试验研究。结果表明,将氟化物浓度为1.75 mg/L的高氟水降至1.0 mg/L以下,每吨水活性氧化铝和活性氧化镁的投加量分别为20kg和1.5 kg。活性氧化铝吸附法适用于原水氟化物超标倍数低,且总硬度偏低的高氟水水质;活性氧化镁吸附法适用于原水氟化物超标倍数较高,且总硬度偏低的高氟水水质。同时,对两种吸附剂在除氟效果、处理成本、处理周期、出水量等方面作了比较。从整体上看,活性氧化镁的除氟效果优于活性氧化铝。实践中需根据具体的水质情况来选择合适的除氟方法。     

活性炭在环境工程中的应用

本文综述了活性炭在处理工业污染方面的用途及特点，并提出了一些应用方面的不足，对活性炭在环境工程 的应用有参考价值。     

生物活性滤池中微生物的生长研究

研究了活性炭一石英砂双层滤料生物活性滤池的挂膜过程。结果表明，在生物活性滤池中，微生物的生长速度是不同的：异养细菌生长速度最快，亚硝化细菌次之，硝化细菌最慢，整个挂膜过程历时3个月。在生物活性滤池内，异养细菌、亚硝化细菌和硝化细菌等三大微生物类群之间无明显的竞争关系，在后两者之间表现为互生关系；而在各个类群内部成员之间则表现为对基质的竞争关系。     

Climatic aspects of urban design in tropical regions

The paper describes the climatic characteristics relevant to urban and building design in hot-humid and in hot-dry tropical regions, respectively. It then discusses the different human comfort issues, the design objectives and the urban design elements which affect and can modify the urban microclimate. The design elements discussed in the paper are: location of towns in a region, density of the built-up area and building's configurations, orientation and width of streets, building design details affecting the comfort of people outdoors, and the design details of “green” areas.The appropriate (from the climatic aspect) design details of the above urban design elements, and some comments on building design in tropical regions, are discussed with respect to each climate type. Subjects of needed research on issues concerning comfort and design problems in tropical cities, on which more knowledge is needed, are suggested.The paper is based on a recent WMO Document (Givoni, 1989, WCAP-10, WMO/TD, No. 346).     

Quantification of spatial structures in two landscape regions

１ＩｎｔｒｏｄｕｃｔｉｏｎＬａｎｄｓｃａｐｅｅｃｏｌｏｇｙｆｏｃｕｓｅｓｏｎｓｔｒｕｃｔｕｒｅ，ｆｕｎｃｔｉｏｎ，ａｎｄｃｈａｎｇｅｓｉｎｌａｎｄｓｃａｐｅ（Ｆｏｒｍａｎ，１９８６）．Ｈｅｔｅｒｏｇｅｎｅｉｔｙｉｎｌａｎｄｓｃａｐｅｓｉｓｓｈａｐｅｄ...     

重点区域建设用地污染地块特征分析

以我国工业发展的重点区域京津冀、长三角和珠三角为研究对象,基于2018～2021年纳入《建设用地土壤污染风险管控和修复名录》的共496个污染地块,对其区域分布、土壤和地下水超标污染物特征、污染的行业相关性、场地地质条件等数据进行相关数据统计分析.结果表明:京津冀污染地块主要分布于京津和冀南,长三角污染地块数量最大且分布广,珠三角污染地块则密布于珠江口.整体上土壤污染以重金属-有机复合污染为主(48.43%),地下水则是有机污染占比(42.49%)最大.化学原料及化学品制造业和金属冶炼及延压加工业污染地块风险负荷指数大于0.25,为较高风险;塑料和橡胶制品业、机械制造、金属制品业、电器机械及器材制造业和皮革、皮毛制造业污染地块为中风险,其余行业污染地块为低风险.场地土壤和地下水污染分布与历史行业类型息息相关,如土壤中化学原料及化学品制造业超标污染物种类最复杂,卤代烃(占比12%)和苯系物(占比10.4%)相比其余行业占比更重,地下水中各行业重金属污染和常规指标如氨氮需要关注.土层深度上各类典型污染物最大超标普遍分布在0～5m,整体上重金属最大污染超标深度大于有机污染最大超标深度;土壤性质...     

Arsenic speciation in fish from Greek coastal areas

Arsenic speciation analysis was conducted on fish samples(sardine and anchovy) collected from six areas along the Greek coastline, i.e. Artemisium Straits, Thermaikos Gulf, Amvrakikos Gulf,Strymonian Gulf, Thracian Sea, and Elefsina Gulf. Total arsenic levels ranging from 11.8 to62.6 mg As/kg dry weight were determined. Arsenobetaine, a non-toxic form of arsenic, was found to be the main arsenic species, present at 8.6 to 58.8 mg As/kg dry weight, accounting for67–95% of the total arsenic. Also detected in all fish samples was dimethylarsinic acid, although at considerably lower concentrations, ranging from 0.072–0.956 mg As/kg dry weight.Monomethylarsonic acid was detected at low levels in all anchovy samples, and only in sardines from one area. Finally, inorganic arsenic in the form of arsenate was detected only in fish at one area, indicating the possible effect of an environmental parameter on its presence at detectable amounts. Statistical analysis revealed the environmental variables, such as salinity,total organic carbon and nitrogen, ammonium, phosphate, total phosphorus, dissolved oxygen and pressure index, are potentially correlated to As species concentrations. Furthermore, based on factor analysis, the biological parameters, such as fish weight, lipids, protein and ash content,that are correlated to As species concentrations of fish were also identified. The interrelationship of arsenobetaine and dimethylarsinic acid concentrations within each fish species was evaluated.     

Inhibitory influence of the connecting strands in fish

The Science of Nature -     

在役石化装置HAZOP分析实例

结合实例讨论在役装置的危险与可操作分析。通过应用经验法、程序HAZOP分析等,结合本装置和同类装置的运行经验,评估技术文件中的操作要求,有助于更好地实现在役装置的系统性风险识别和控制。