分布式热电联产系统制约因素探讨     

黄逊青 《中国勘察设计》2006,(5):36-39

本文讨论商用和民用小型分布式热电联产系统的能源利用效率、公众安全和环境保护问题。指出由于安装、运行场所为城市中心地区或居民住宅区，公众的生命财产安全是考虑技术方案的优先问题，对周围环境影响的考虑应优先于能源利用效率和经济效益；若小型分布式热电联产系统把一次能源转换过程产生的污染物和余热的排放地点转移到城市内的建筑物和住宅区，有关地区的大气环境质量不可避免受到影响；分布式热电联产系统的使用还存在资源制约的问题。因此，应规范在城市中心地区和居民住宅区设置分布式热电联产系统。  相似文献   

Evaluation of site effects using numerical and experimental analyses in Città di Castello (Italy)     

F. Pergalani  R. de Franco  M. Compagnoni  G. Caielli 《Soil Dynamics and Earthquake Engineering》2006,26(10):941-951

In the paper the results of the numerical and experimental analyses, at a site in the Umbria Region (Città di Castello—PG), are finalized and the evaluations of site effects are shown. The aim of the work was to compare the two types of analyses and give some methodologies that may be used at the level of urban planning. Therefore a series of geological, geomorphological (1:5.000 scale), geotechnical and seismic analyses have been carried out, to characterize the lithological units and to identify the areas affected by site effects. The expected seismic inputs were provided and two-dimensional numerical analyses have been done. An experimental analysis, using the registrations of small events, has been done. The results for the two approaches were performed in terms of elastic pseudo-acceleration spectra and amplification factors. The results are given as a ratio between spectral intensity, calculated using the pseudo-velocity spectra, in the periods of 0.1–0.5 s and 0.1–2.5 s of output and input. The results have been analyzed and compared, to provide a methodology that may be comprehensive and precise.  相似文献   

Monitoring the Sensible Heat Flux over Urban Areas using Large Aperture Scintillometry: Case Study of Marseille City During the Escompte Experiment     

J. -P. Lagouarde  M. Irvine  J. -M. Bonnefond  C. S. B. Grimmond  N. Long  T. R. Oke  J. A. Salmond  B. Offerle 《Boundary-Layer Meteorology》2006,118(3):449-476

Abtract Sensible heat flux estimated by Large Aperture Scintillometry (LAS) has been tested against the more traditional eddy covariance technique over Marseille city centre, a reasonably homogeneous surface. Over the 3 week test period fluxes were found to be similar, yet less noisy for the LAS due to the spatial integration. No systematic bias between the estimates was found as a function of wind direction, indicating the homogeneity of the site. Sensitivity analysis of the required aerodynamic parameters shows that careful attention must be paid to the displacement height along the measurement path. Spatial variability of surface sensible heat flux is studied via a second LAS measurement path over the city.  相似文献   

A spatial–temporal point process model of rainfall for the Thames catchment, UK     

Paul S.P. Cowpertwait   《Journal of Hydrology》2006,330(3-4):586-595

A spatial–temporal point process model of rainfall is fitted to data taken from 23 sites across the Thames catchment, London. For the period January 1970 to December 1988 the sites have daily data, whilst for the period January 1989 to November 2003 the sites have hourly data. In addition, the records contain missing values. The fitted model is used to infill the missing values, to disaggregate the daily data to hourly data and to generate spatially consistent series at a further 25 sites across the catchment. The model is validated by considering statistical properties that are not used in the fitting procedure, which include extreme values, the proportion of dry intervals, and annual totals. Overall the performance of the model is good, with the exception of an over-estimation in cross-correlation between pairs of sites for the disaggregated series.  相似文献   

The impact of stormwater on a soil profile in an infiltration basin     

T. Winiarski  J.-P. Bedell  C. Delolme  Y. Perrodin 《Hydrogeology Journal》2006,14(7):1244-1251

The effects of urban stormwater on the soil of an infiltration/ holding basin were studied within the framework of research carried out by OTHU (Urban Hydrology Field Observatory of Lyon, France). The biophysicochemical impacts of stormwater from an industrial watershed on the local soil (to a depth of 4 m in the unsaturated zone) were measured. Several types of measurement (pH, organic matter, particle size, heavy metals content, and heterotrophic viable bacterial counts) for three vertical soil profiles were carried out. High concentrations of heavy metals and significant variations in pH and silt to a depth of 1.5 m were observed. The concentrations decreased as a function of distance from the stormwater discharge pipe. Changes in the bacterial population were also observed, varying in accordance with the depth and location of the profile.

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Resumen Se estudiaron los efectos de tormentas en zonas urbanas sobre el suelo de una cuenca retenedora/de infiltración dentro del marco de investigación llevado a cabo por OTHU (Laboratorio de Observación de Campo de Hidrología Urbana, Lyon, Francia). Se midieron los impactos biofisicoquímicos de la tormenta en una cuenca industrial sobre el suelo local (a una profundidad de 4m en la zona no saturada). Se llevaron a cabo varios tipos de mediciones (pH, materia org′nica, tama?o de partículas, contenido de metales pesados, y conteo de bacterias viables heterotróficas) en tres perfiles ed′ficos. Se observaron altas concentraciones de metales pesados y variaciones significativas en pH y limo a una profundidad de 1.5m. Las concentraciones disminuyeron en función de la distancia del tubo de descarga de las aguas de la tormenta. También se observaron cambios en las poblaciones de bacterias los cuales variaban en función de la profundidad y localización del perfil.

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Résumé Dans le cadre de la fédération de recherche OTHU (Observatoire de Terrain en Hydrologie Urbaine de Lyon) une étude sur l’impact des eaux pluviales sur le sol d’un bassin d’infiltration / rétention est présentée. Il s’agit d’évaluer l’impact biophysicochimique des eaux pluviales issues d’un bassin versant industriel sur une profondeur d’environ 4 m de zone non saturée. Pour cela plusieurs types de mesures ont été effectuées (pH, perte au feu, teneur en Cu, Pb, Cd, dénombrement bactérien) suivant trois profils verticaux. Les résultats montrent des concentrations importantes de métaux et des variations de pH jusqu’à 1.5 m de profondeur. De plus, les résultats montrent une variation suivant la position des points de prélèvements. Des modifications de la population bactérienne sont également observées suivant la profondeur et l’emplacement des profils.

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基于MO和ArcSDE的城镇地籍建库工具箱开发与应用     

黄华国  汤军  王蕾 《国土资源信息化》2005,(1):32-34,44

城镇地籍数据建库是一项系统性、工程性和技术性相结合的工作。为了高效地、高质 量地、高水平地完成测绘数据的交换处理、权属数据的录入和图属一致控制,开发并 应用一套城镇地籍建库工具集具有极其重要的意义。本文基于MO和ArcSDE设计并 开发了企业级的建库工具箱,集中了各个环节的工具,为北京市城镇地籍建库提供了 有力支持。  相似文献   

A transboundary study of urban sprawl in the Pacific Coast region of North America: The benefits of multiple measurement methods     

Chris Davis  Tim Schaub   《International Journal of Applied Earth Observation and Geoinformation》2005,7(4):268-283

Sprawling urban development has emerged as a primary concern of policy makers, land preservationists and both urban and rural communities in developing regions across the globe. For the first time in history, more global residents lived in urban areas than not and the trend to urbanization is in full force at the start of the 21st century. An understanding of the nature and character of urban sprawl is complicated by a failure to satisfactorily define it and by the limitations of measurement techniques designed to characterize complex landscape forms. Like other landscape patterns, the quantification of urban sprawl is highly spatially and temporally scale-dependent. This paper summarizes a recent project to measure urban sprawl in the transboundary region of the Pacific Coast of North America. The metropolitan centers of Portland, OR, Seattle, WA and Vancouver, BC, span two nations, three state/provincial governments and dozens of cities. As a region, this was a global leader in population growth in the 1990s. The study relied on three separate methods – an impervious surface metric, a neighborhood density metric and a building permit metric – for quantifying urban growth. The results provide insight on the strengths and shortcomings of different methods with respect to the challenges posed by data availability and format. Taken together they demonstrate the richer understanding that combined methods may offer in characterizing phenomena as difficult to communicate and agree upon as urban sprawl.  相似文献   

Accumulation and sources of heavy metals in urban topsoils: a case study from the city of Xuzhou, China   总被引：8，自引：0，他引：8  

Xue Song Wang  Yong Qin  Shu Xun Sang 《Environmental Geology》2005,48(1):101-107

The knowledge of the variability, the anthropogenic versus natural origin and corresponding environmental risk for potentially harmful elements in urban topsoils is of importance to assess human impact. The aims of the present study were: (1) to assess the distribution of heavy metals (Sn, Li, Ga, Ba, Fe, Mn, Co, Be, Ti, Al, Hg, Cr, Sb, As, Bi, Pd, Pt, Au, Ni, Cd, Zn, Cu, Pb, Se, Mo, Sc and Ag) in urban environment; (2) to discriminate natural and anthropogenic contributions; and (3) to identify possible sources of pollution. Multivariate statistic approaches (principal component analysis and cluster analysis) were adopted for data treatment, allowing the identification of three main factors controlling the heavy metal variability in Xuzhou urban topsoils. Results demonstrate that Hg, Cr, Sb, As, Bi, Pd, Pt, Au, Ni, Cd, Br, Zn, Cu, S, Pb, Se, Mo, Sc and Ag could be inferred to be tracers of anthropogenic pollution, whereas Al, Ti, Ga, Li, V, Co, Pt, Mn and Be were interpreted to be mainly inherited from parent materials. Iron, Ba, Sn, Pd and Br were interpreted to be affected by mixed sources.  相似文献   

Effects of land use on the spatial distribution of trace metals and volatile organic compounds in urban groundwater, Seoul, Korea   总被引：4，自引：0，他引：4  

Seong-Sook Park  Soon-Oh Kim  Seong-Taek Yun  Gi-Tak Chae  Soon-Young Yu  Seungki Kim  Young Kim 《Environmental Geology》2005,48(8):1116-1131

To investigate the urban groundwater contamination by eight trace metals and 69 volatile organic compounds (VOCs) in relation to land use in Seoul, a total of 57 groundwater samples collected from wells were examined using a non-parametric statistical analysis. Land use was classified into five categories: less-developed, residential, agricultural, traffic, and industrial. A comparison of analyzed data with US EPA and Korean standards for drinking water showed that some metals and VOCs exceeded the standards in a few localities, such as Fe (N=5), Mn (N=6), Cu (N=1), TCE (N=6), PCE (N=8), 1,2-DCA (N=1), and 1,2-dichloropropane (N=1). Among the 69 investigated VOCs, 19 compounds such as some gasoline-related compounds (e.g., toluene) and chlorinated compounds (e.g., chloroform, PCE, TCE) were detected in groundwater. Non-parametric statistical analysis showed that the concentrations of most trace metals (Fe, Mn, As, Cr, Pb, Cd) and some VOCs (especially, TCE, PCE, chloroform; toluene, carbon tetrachloride, bromodichloromethane, CFC113) are significantly higher in the industrial, residential, and traffic areas (P<0.05), indicating that anthropogenic contamination of urban groundwater by those chemicals is growing. Those chemicals can be used as effective indicators of anthropogenic contamination of groundwater in urban areas and therefore a special attention is warranted for a safe water supply in those areas. The results of this study suggest that urban groundwater quality in urban areas is closely related with land use.  相似文献   

超细粉末团聚机理及其消除方法   总被引：16，自引：0，他引：16       下载免费PDF全文

李召好  李法强  马培华 《盐湖研究》2005,13(1):31-36

对超细粉末的团聚机理进行了介绍,分析了粉体制备过程中团聚现象产生的原因以及消除团聚的方法。  相似文献