环境科学研究与科研人员的智力结构

本文结合环境科研的全方位交叉和渗透、环境问题的滞后与环境科研的尾随性、环境问题的整体性层次性与科研选题的系统配套、环境问题与环境科研的国际性等特点,分析论证了建立以科研人员个体为基础并以科研群体来完善的四维模型知识结构的必要性。 接着,在讨论知识结构与智力结构的区别和联系之后,作者从环境科研特点和实践经验出发,系统地论述了科研人员应有的智力结构、智力结构优化与个性心理品质、个体智力结构优化与群体智力结构的最佳配置问题。 作者最后强调,为了多水平的科研成果和人才,必须高度重视科研人员的智力发展和智力效应这个根本条件。      

深圳地铁一期工程施工安全管理概况

我国越来越多城市正在新建、扩建或计划建设地铁,而地铁安全生产文明施工是值得地铁工程建设安全生产责任单位非常关注、重视的课题.结合安全生产有关法律法规,重点针对建设单位在建设工程中的安全责任,介绍深圳地铁一期工程的主要安全管理工作.     

Analysis of gas flow behavior in an annular fluidized-bed reactor for polystyrene waste treatment

The characteristics of bubble properties and the chaotic flow behavior of gas were investigated in an annular fluidized bed (0.102 m in inner diameter and 2 m in height) because the behavior of gas flow in such a reactor is one of the important factors governing reactor operation, reactor performance, and the reaction itself. Pressure fluctuations as a state variable for the analysis of gas flow behavior were measured and analyzed. Bubble properties were determined by adopting the cross-correlation function of pressure fluctuations. The resultant chaotic flow behavior of gas was interpreted by means of chaotic parameters such as the Kolmogorov entropy. It was found that the Kolmogorov entropy could be utilized effectively to explain the nonlinear dynamic behavior of gas-solid flow in the annular fluidized bed. The pierced length and rising velocity of bubbles increased with increasing gas velocity, bed temperature, and particle size of the bed material. The bubble frequency increased with increasing gas velocity and bed temperature, while it decreased with increasing particle size of the bed material. Correlations to predict the bubble properties in annular fluidized-bed reactors were suggested.     

室内外空气污染对学龄儿童呼吸系统影响的研究

通过对污染区和对照区 2 0 0 0多名学龄儿童呼吸系统症状、疾病患病率比较 ,并运用非条件 Logistic回归分析方法 ,就室内外空气污染对学龄儿童呼吸系统健康的影响 ,进行了研究。结果显示 ,污染区室内外空气污染较严重 ,大气中TSP、SO2 和 NOx 的浓度均超过国家二级标准 ,其儿童呼吸系统症状、疾病患病率明显高于对照区。对儿童呼吸系统发病有显著影响的环境因素是 :大气污染、被动吸烟、家庭燃煤、冬季取暖和室内油烟污染程度。其中咳嗽与以上五个因素有显著的正相关关系 (P<0 .0 5) ;除被动吸烟外 ,支气管炎与其它四个因素呈显著正相关 (P<0 .0 5) ;咳痰与大气污染、被动吸烟、冬季取暖和室内油烟污染程度 ,气喘和呼吸系统疾病住院率与大气污染和室内油烟污染正相关关系显著 (P<0 .0 5)。哮喘与室内外空气污染无显著的统计学联系     

Environmental estrogenic effects and gonadal development in wild goldfish (Carassius auratus)

Serum vitellogenin (VTG) contents of wild goldfish (Carassius auratus) were investigated as a sensitive biomarker for artificial estrogenic compounds in aquatic environments. Goldfish was sampled from a pristine area, a river situated 5 km downstream from a sewage treatment works (STW), and also from the Young-San River in Korea. The female yolk precursor protein VTG was not detected when gonadosomatic index (GSI) was less than 0.85%, while VTG levels of >10 microg/ml were found in males whose GSI was less than 1.53%. In male goldfish sampled from STW and the Young-San River, the higher VTG corresponded to lower GSI. This study suggested a trend that gonad development was connected to VTG levels in both sexes, and the application of GSI and histological analysis provide an attractive possibility that it could be included in the panel of markers used for estrogenic activity investigation of aquatic environments.     

地下车库防排烟和通风系统设计

本文介绍了地下汽车库的通风与排烟系统设计,探讨了地下车库通风与排烟系统的形式,并提出了地下汽车库通风与排烟系统合一的可行性.分析了传统通风方式的利弊,对无风管诱导通风系统在地下车库中的应用作了介绍.指出车库诱导通风系统和传统防排烟与通风系统相结合的优越性.     

Baseflow nitrate in relation to stream order and agricultural land use

Management of agricultural nonpoint-source pollution continues to be a challenge because of spatial and temporal variability. Using stream order as an index, we explored the distribution of nitrate concentration and load along the stream network of a large agricultural watershed in Pennsylvania-the East Mahantango Creek Watershed and two of its sub-watersheds. To understand nitrate concentration variation in the stream water contributed from ground water, this study focused on baseflow. Impacts of agricultural land use area on baseflow nitrate in the stream network were investigated. Nitrate concentration showed a general decreasing trend with increasing stream order based on stream order averaged values; however, considerable spatial and temporal variability existed within each snapshot sampling. Nitrate loads increased with stream order in a power function because of the dominant effect of stream flow rate over the nitrate concentration. Within delineated sub-watersheds based on stream orders, positive linear functions were found between agricultural land use area percentage and the baseflow nitrate concentration and between agricultural drainage area and the nitrate load. The slope of the positive linear regression between the baseflow nitrate concentration and percent agricultural land area seems to be a valuable indicator of a watershed's water quality as influenced by agricultural practices, watershed size, and specific physiographic setting. Stream order seems to integrate, to a certain degree, the source and transport aspects of nonpoint-source pollution on a yearly averaged basis and thus might provide a quick estimate of the overall trend in baseflow nitrate concentration and load distribution along complex stream networks in agricultural watersheds.     

云南省主体功能区综合交通运输网络建设对区域可达性影响

云南省地处我国西南边疆,随着经济的发展,交通可达性正逐渐成为该省经济发展的“瓶颈”。从可达性的概念入手,分析了目前云南省交通运输网络建设的空间格局及各类主体功区内存在的主要问题,针对各类功能区内交通运输结构中存在的问题给出了合理化建议,以期提高云南省交通的可达性。     

Cement paste column for simultaneous removal of fluoride, phosphate, and nitrate in acidic wastewater

Cement paste, a cured mixture of cement and water, was reported to have considerable capacity for fluoride removal. In this study, heavily mixed fluoric acid wastewater from a semiconductor fabrication plant was applied to a column packed with cement paste granules to evaluate its capacity for the removal of fluoride and three other contaminants, phosphate, nitrate, and sulfate, as well as to investigate the interactions between these contaminants and cement components. The column reduced fluoride to remarkably low levels since fluorite was formed at highly elevated concentrations of calcium and the residual fluoride was further sorbed into the amorphous calcium phosphate that precipitated the entire amount of phosphate until breakthrough. The simultaneous removal of sulfate in the earlier stage was followed by significant removal of nitrate in exchange with the gradual release of sulfate. This behavior was explained by the co-precipitation of sulfate with calcium phosphate or calcium aluminate solids and the subsequent substitution of nitrate for the interlayer sulfate of monosulfate. However, the overall removal capacity of cement paste was reduced due to the high effluent loss of calcium and competition for calcium between fluoride and phosphate.     

Stressor identification and health assessment of fish exposed to wastewater effluents in Miho Stream, South Korea

This study evaluated the effects of an industrial wastewater treatment plant (IWTP) and a municipal wastewater treatment plant (MWTP) effluents on a variety of bioindicators ranging from biochemical, organism, and population-level responses in pale chub (Zacco platypus) and fish community structure. The Index of Biotic Integrity (IBI) indicated that the site upstream of these wastewater treatment plant discharges is in fair–good condition and downstream of the plant is in poor condition. The EROD (ethoxyresorufin-O-deethylase) activity, condition factor, and liver somatic index were significantly increased at the downstream site compared to those of the upstream site. The most significant change observed in pale chub population in the downstream site of the Miho Stream, relative to the upstream population, was the total absence of an younger age group. Stressors impacting the downstream site were identified as mostly organic or nutrient enrichment and habitat degradation associated with wastewater treatment plants. The results of causal analysis suggest that the primary causes affecting fish population in the downstream site are through both size-selective mortality caused by ammonia toxicity and recruitment failure caused by habitat degradation and reproduction problem due to an IWTP and MWTP effluents.