室内空气污染对人类健康的影响及防治措施

本文通过论述第三污染源室内空气污染对人类健康的危害,并提出了主要防治措施。     

基于系统动力学模型的清河流域产业结构优化研究

基于清河流域近年的"经济-社会"现状特点与发展趋势,以2010年为水平基准年,建立清河流域产业结构优化SD模型,将整个系统分为人口及生活子系统、经济子系统、用水子系统和污染物子系统。设置四种情景方案进行模拟,模拟时间为2010年到2020年,通过各个方案结果对比分析选出方案四为最优方案。并根据最优方案提出清河流域产业结构优化的建议,从而为清河流域经济的健康可持续发展提供科学的决策依据。     

Triboelectric charging behavior of wood particles during pellet handling processes

Electrostatic charges accumulated on wood particles through triboelectrification during their transportation and handling processes can cause hazardous electrical discharge which may further trigger dust explosion. In this work, tribo-charging behavior of different kinds of wood particles was investigated by a vibrating plate charging method. It was found that reduction in the work function difference between contact bodies might contribute to the reduction of tribo-charge generation, while the reduction of electrical resistivity of wood pellets could effectively accelerate the charge dissipation. As the particle size decreases, accumulated charges increase significantly. In contrast, higher moisture content of wood particles leads to lower charge accumulation due to an accelerated charge dissipation rate. Tribo-charging behaviors of white pellets, torrefied pellet, steam treated pellets and dark pellets have also been investigated. Compared to the white pellets, they all have shown a reduction on charge accumulation to some extent. However, results suggested that all of them have nearly equivalent tribo-charge density as coal and wheat grains used as references in this study.     

Study of the Optimization and Adjustment of the Industrial Structure Subjected to Water Resource in the Drainage Area of the Yellow River

Abstract

Since the 1990s, the Yellow River stream has been temporarily interrupted for several years, which affects the development of society, the economy and human life, limits the economic potential of the drainage areas, and especially causes great harm to regions on the lower reaches. Based on the analysis of the relationship between the development of society and economy and water scarcity, the author thinks it is necessary to optimize and adjust the industrial structure that has extravagantly consumed enormous amounts of water, and to develop ecological agriculture, industry and tourism which are balanced with the ecological environment. Finally, the author puts forward several pieces of advice and countermeasures about how to build the economic systems by which water can be used economically.     

Spatial assessment for groundwater quality based on GIS and improved fuzzy comprehensive assessment with entropy weights

The objective of the research is to evaluate spatial groundwater quality based on improved fuzzy comprehensive assessment model with entropy weights(FCAEW)in geographical information system(GIS)environment.This paper explores the method of comprehensive evaluation of groundwater and sets up an evaluation model applying GIS and FCAEW.Groundwater samples were collected and analyzed from 29 wells in Zhenping County,China.Six parameters were chosen including chloride,sulfate,total hardness,nitrate,fluoride and color.Better spatial interpolation methods for evaluated parameters are found out and selected according to the minimum cross-validation errors from the interpolation methods.FCAEW model was carried out with the help of GIS which makes the evaluating process simpler and easier and more automatically,effectively,efficiently and intelligently.The result embodies the feasibility and effectiveness of FCAEW in GIS when compared with other comprehensive evaluation methods.     

Fabrication and performance of PET mesh enhanced cellulose acetate membranes for forward osmosis

Polyethylene terephthalate mesh(PET) enhanced cellulose acetate membranes were fabricated via a phase inversion process. The membrane fabrication parameters that may affect the membrane performance were systematically evaluated including the concentration and temperature of the casting polymer solution and the temperature and time of the evaporation, coagulation and annealing processes. The water permeability and reverse salt flux were measured in forward osmosis(FO) mode for determination of the optimal membrane fabrication conditions. The optimal FO membrane shows a typical asymmetric sandwich structure with a mean thickness of about 148.2 μm. The performance of the optimal FO membrane was tested using 0.2 mol/L Na Cl as the feed solution and 1.5 mol/L glucose as the draw solution. The membrane displayed a water flux of 3.47 L/(m2·hr) and salt rejection of95.48% in FO mode. While in pressure retarded osmosis(PRO) mode, the water flux was4.74 L/(m2·hr) and salt rejection 96.03%. The high ratio of water flux in FO mode to that in PRO mode indicates that the fabricated membrane has a lower degree of internal concentration polarization than comparable membranes.     

Characteristics of atmospheric single particles during haze periods in a typical urban area of Beijing: A case study in October, 2014

To investigate the composition and possible sources of particles, especially during heavy haze pollution, a single particle aerosol mass spectrometer (SPAMS) was deployed to measure the changes of single particle species and sizes during October of 2014, in Beijing. A total of 2,871,431 particles with both positive and negative spectra were collected and characterized in combination with the adaptive resonance theory neural network algorithm (ART-2a). Eight types of particles were classified: dust particles (dust, 8.1%), elemental carbon (EC, 29.0%), organic carbon (OC, 18.0%), EC and OC combined particles (ECOC, 9.5%), Na-K containing particles (NaK, 7.9%), K-containing particles (K, 21.8%), organic nitrogen and potassium containing particles (KCN, 2.3%), and metal-containing particles (metal, 3.6%). Three haze pollution events (P1, P2, P3) and one clean period (clean) were analyzed, based on the mass and number concentration of PM_2.5 and the back trajectory results from the hybrid single particle Lagrangian integrated trajectory model (Hysplit-4 model). Results showed that EC, OC and K were the major components of single particles during the three haze pollution periods, which showed clearly increased ratios compared with those in the clean period. Results from the mixing state of secondary species of different types of particles showed that sulfate and nitrate were more readily mixed with carbon-containing particles during haze pollution episodes than in clean periods.     

上海市用水量与经济发展的关系研究

选取上海市1998～2006年的用水量、经济数据,通过人均GDP与人均用水量之间的关系,探索上海市用水量与经济发展是否存在环境库兹涅茨曲线关系,剖析上海市经济增长与用水量的演变规律,结果表明：上海市经济增长与用水量之间不符合一般的环境库兹涅茨曲线特征,重新建立了曲线模型,通过模型计量分析,人均总用水量,人均农业用水量,人均生活用水量与人均GDP曲线均为“U＋倒U”形,而人均工业用水量人均GDP曲线为“倒U＋U”形,为合理开发上海市水资源提供较为科学严谨的依据。     

模拟盐碱胁迫对小麦种子萌发的影响

农田土壤盐碱化已经成为影响小麦种子萌发的一个重要因素。利用NaCl和Na2CO3模拟盐碱胁迫对小麦种子的萌发影响实验表明：四种小麦的萌发率均表现出显著差异,并随着浓度的增加而表现出降低的趋势,并与无盐碱胁迫的萌发率表现相一致,其萌发率及萌发耐盐碱性次序高低顺序为：济南17〉淄麦12〉邯6172〉泰山9818。在单一盐或碱胁迫条件下,小麦的萌发率总是随着NaCl或Na2CO3浓度的增加而表现出不同程度的降低。无论以NaCl浓度增加为主还是以Na2CO3浓度增加为主的情况下,小麦种子的萌发均随着浓度的增加受到明显的抑制作用。盐碱复合胁迫对小麦种子萌发的影响机理还缺乏生物学及生理学上的解释,仍需要进行深入研究。     

Evaluation of the readsorption of plutonium and americium in dynamic fractionations of environmental solid samples

A dynamic extraction system exploiting sequential injection (SI) for sequential extractions incorporating a specially designed extraction column is developed to fractionate radionuclides in environmental solid samples such as soils and sediments. The extraction column can contain up to 5 g of a soil sample, and under optimal operational conditions it does not give rise to creation of back pressure. Attention has been placed on studies of the readsorption problems during sequential extraction using a modified Standards, Measurements and Testing (SM&T) scheme with four-step sequential extractions. The degree of readsorption in dynamic and conventional batch extraction systems is compared and evaluated by using a double-spiking technique. A high degree of readsorption of plutonium and americium (>75%) was observed in both systems, and they also exhibited similar distribution patterns of the two radionuclides. However, the dynamic system is fully automated, eliminates manual separations, significantly reduces the operational time required, and offers detailed kinetic information.