黄浦江上游汇水区禽畜业污染及其防治对策

为定量了解黄浦江上游汇水区禽畜业污染对黄浦江水网地区水环境的影响程度,对汇水区的禽畜业现状进行了调查,提出了各类禽畜的粪尿及其污染物的排泄系统,估算了禽畜粪尿总产生量及流失量。结果表明,汇水区禽畜粪尿流失量达91.3万t/a,由此产生的污染物COD_(Cr)为5.32万t/a,NH_3-N为0.58万t/a,分别是汇水区污染总负荷的38.3％和47.8％,成为黄浦江上游汇水区的主要污染源。对此,提出了防治禽畜业污染的几点对策与建议。     

WATER QUALITY IN SHALLOW ALLUVIAL AQUIFERS,UPPER COLORADO RIVER BASIN,COLORADO, 19971

ABSTRACT: Shallow ground water in areas of increasing urban development within the Upper Colorado River Basin was sampled for inorganic and organic constituents to characterize water‐quality conditions and to identify potential anthropogenic effects resulting from development. In 1997, 25 shallow monitoring wells were installed and sampled in five areas of urban development in Eagle, Grand, Gunnison, and Summit Counties, Colorado. The results of this study indicate that the shallow ground water in the study area is suitable for most uses. Nonparametric statistical methods showed that constituents and parameters measured in the shallow wells were often significantly different between the five developing urban areas. Radon concentrations exceeded the proposed USEPA maximum contaminant level at all sites. The presence of nutrients, pesticides, and volatile organic compounds indicate anthropogenic activities are affecting the shallow ground‐water quality in the study area. Nitrate as N concentrations greater than 2.0 mg/L were observed in ground water recharged between the 1980s and 1990s. Low concentrations of methylene blue active substances were detected at a few sites. Total coliform bacteria were detected at ten sites; however, E. coli was not detected. Continued monitoring is needed to assess the effects of increasing urban development on the shallow ground‐water quality in the study area.     

带毂直齿圆柱齿轮精锻的计算机模拟

此文利用上限法建立带毂直齿圆柱齿轮精锻过程的数学模型,并利用该模型对带毂直齿圆柱齿轮精锻过程中坯料外形尺寸和力一行程曲线进行了计算机模拟。对所得结果作了实验校核。实验结果与模拟结果吻合得较好,证明此文所建立的数学模型和模拟方法是可行的。     

黄骅坳陷孔古4井原油的成因探讨

通过对黄骅孔古4井上古生界原油的地球化学特征及其与石炭系煤系烃源岩的亲缘关系研究,特别是与奥陶系原油、灰岩、下第三系原油饱和烃的甾、萜烷精细“指纹”对比研究后,我们认为孔古4井原油应属于上古生界煤系地层自生自储的原生油气藏,而并非下第三系抑或下古生界碳酸盐岩所生。孔古4井上古生界原生油气藏的发现对于华北地区特别是华北北部黄骅坳陷上古生界煤系地层的油气勘探具有重要意义。     

锥形凹模内挤压/拉拔过程的上限解分析

论述了适用于分析锥形凹模内挤压/拉拔过程的几种上限模型,分析了采用一般模型得到的上限解.     

鄂尔多斯盆地上古生界天然气的运移与聚集

通过对上古生界烃源岩天然气排气史、天然气运移方向和沉积相带的展布等综合分析 ,可将上古生界天然气的运移聚集分为三叠纪—早白垩世和早白垩世后两个阶段。在三叠纪—早白垩世阶段 ,天然气运移方向主要是向北 ,而在早白垩世后阶段 ,天然气主要是就近运移聚集而成藏 ,这一阶段是鄂尔多斯盆地上古生界天然气重要的运移与聚集期 ,故上古生界煤成气藏的成藏期较晚。鄂尔多斯盆地北部和中部的靖边古三角洲是天然气聚集的有利地区 ,具有较好的天然气勘探前景     

Spatially constrained clustering and upper level set scan hotspot detection in surveillance geoinformatics

We discuss upper level set (ULS) scan as a type of spatially constrained clustering in relation to two ways of imposing the spatial constraint, retrospectively versus progressively. We show that ULS scan produces the same results both ways; whereas two popular clustering techniques, single-linkage and K-means, can yield different results when spatial constraints are imposed retrospectively versus progressively. The ULS scan approach examines spatially connected components of a tessellation as a threshold is moved from the highest level (value) in the data to the lowest level. When the variable of interest on the tessellation is a rate of incidence, then a significance test is available based on binomial or Poisson null models and Monte Carlo techniques. This is a common context for detecting hotspots of diseases in epidemiological work. We also discuss an approach for extending the univariate methodology to accommodate multivariate contexts. Received: September 2005 / Revised: February 2006 This material is based upon work supported by (i) the National Science Foundation under Grant No. 0307010, (ii) the United States Environmental Protection Agency under Grant No. CR-83059301 and (iii) the Pennsylvania Department of Health using Tobacco Settlement Funds under Grant No. ME 01324. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the agencies.     

Geochemical Distribution and Bioavailability of Heavy Metals and Oxalate in Street Sediments from Rio de Janeiro, Brazil: A Preliminary Investigation

As urbanisation accelerates within less-economically developed countries, populations in cities such as Rio de Janeiro are subject to numerous health risks relating to “heavy metal”, sewage and vehicle pollution. These risks apply especially to children, through inhalation and dermal contact with pollutant-rich street sediments that reflect contamination from atmospheric deposition and act as effective sinks for heavy metals and oxalates. To assess the nature and extent of these risks street sediments were collected from industrial, commercial, residential and recreational areas with varying traffic densities within Rio de Janeiro. A modified selective extraction procedure was used to study the geochemical partitioning and bioavailability of Fe, Mn, Zn, Cu, Cr, Ni, Pb and C₂O ₄ ⁻ . Oxalate partitioning has not been studied by traditional sequential methods and results from this procedure highlight the potential bioavailability of both oxalates and “heavy metals”, especially Pb and C₂O ₄ ⁻ in industrial and recreational areas.     

长江上游高寒草地生态建设和管理中生态理论的若干质疑

现有的草地管理政策和措施建立在西方经典生态学理论的基础上，并在很大程度上改变了传统管理模式．本文针对长江上游高寒草地生态建设与管理中的问题，结合草地生态学的新进展，从草地生态系统特征、多样性与稳定性、草地承载力、平衡与非平衡等几个方面进行了讨论，旨在能引起今后草地生态建设中加强这些方面的针对性研究，并有效地避免由于理论自身偏差而导致不应有的技术失误．本文的中心观点在于，由于长江上游地区的高寒草地处在环境因子剧烈变化的条件之下，草地的生态过程在很大程度上受制于非生物条件(如气候)，而不是生物因子的相互作用(如放牧)，因此，已有的一些草地生态理论不能完全解释草地动态变化的机理，其适用性受到限制，而任何简单套用理论以及基于这些理论发展的技术和模式都有可能给生态治理和管理带来负面影响．图2参22     

浙江省上石炭统-中二叠统生物地层划分进展

本文划分论述了浙江省上石炭统—中二叠统16条化石带（其中11条为新建化石带）,对比研究结果表明它们分布于老虎洞组、黄龙组、船山组、梁山组、栖霞组、孤峰组、龙潭组下部的地层,可分别与滑石板阶、达拉阶、逍遥阶、紫松阶、隆林阶、栖霞阶、祥播阶、茅口阶、冷坞阶等9个阶对比。探讨研究了上石炭统底界、下二叠统底界和中二叠统底界;指出上石炭统未见底,缺失罗苏期的沉积;下二叠统底界位于Sphaeroschwagerina subrotunda带之底,以Sphaeroschwagerina属的始现作为底界的标准;石炭—二叠系界线位于Triticites subcrassulu筵带与Sphaeroschwagerina subrotund筵带之间;中二叠统的底界位于Orthotichia chekiangensis腕足组合带之底,以Orthotichia chekiangensis的始现作为中二叠统底界的标准。进一步论证了船山组是一个跨越石炭—二叠系界线的岩石地层单位,下部归属上石炭统逍遥阶,中部归属下二叠统紫松阶和上部归属下二叠统隆林阶。