金川二矿区不良岩层采场巷道片帮冒顶事故树分析

金川矿区是典型的高地应力矿区。矿区构造极为发育 ,围岩稳定性极差 ,使采矿生产存在事故隐患。针对采场巷道顶板围岩或充填体的片冒事故 ,考虑人、机、环境 ,确定三种不同条件下片冒事故的影响因素 ,进行事故树分析 ,计算事故的最小割集、径集以及影响因素的重要度系数 ,为预防片冒事故提供了重要的理论依据     

模糊故障树分析及其应用研究

基于某些实际情况下系统故障发生概率具有模糊性和不确定性的特点 ,笔者将模糊集理论引入故障树分析并针对自动化立体仓库的故障特征 ,对立体仓库各个环节发生故障时所遇到的各种模糊信息进行了科学的、定量的处理。实例证明 ,该方法是行之有效的 ;它能解决传统故障树分析不能处理同时存在随机不确定性和模糊不确定性的故障事件的问题     

厌氧水解—高负荷生物滤池处理城镇污水的试验研究

厌氧水解－高负荷生物滤池是一种利用附着在塑料模块填料上的微生物系统对城镇污水中的污染物质进行降解处理的绿色环保技术。厌氧水解池和高负荷生物滤池采用的塑料模块填料具有高空隙率、高附着面积、高布水性能和抗堵塞的优异性能,并无须回流。当厌氧水解池水力停留时间为4小时,生物滤池水力负荷为30米^3/米^2。日,该系统处理城镇污水的CODCr去除率达80－86％,BOD5去除率达85％－95％。SS去除率达85－95％,处理后出水上述各项指标均可满足国家二级生物处理排放标准的要求。与广泛运用的活性法处理系统相比,该技术可节约基建投资20％以上,节约能耗50％以上,同时还具有流程简单、管理方便、耐冲击负荷、剩余污泥少等特点。     

高效内循环反应器的污泥特性

采用高效内循环好氧反应器处理废纸脱墨废水,结果表明,在高紊流、高剪切条件下生物活性污泥的粒径减小,使废水、生物污泥、空气充分接触,大大提高了传质速率和污泥的比好氧呼吸速率(SOUR),反应器的容积负荷和COD处理效率可分别达35kg/(m³d)和80%.     

涤纶高弹丝纤维球滤料过滤特性研究

采用自主研制的涤纶高弹丝纤维球滤料对景观水进行过滤试验,研究其过滤特性及相关因素对过滤性能的影响. 结果表明,在不投加任何絮凝剂,滤速为30 m/h,平均进水浊度为87.5 NTU时,纤维球滤料过滤周期达16.5 h左右,出水浊度维持在3～5 NTU.当PAFC投加量为12 mg/L,滤速为30～50 m/h,进水浊度为50～70 NTU时,过滤出水浊度可以维持在1 NTU以下,过滤周期达6 h以上,周期截污量为30～45 kg/m3. 采用气冲－气水联合反冲－水冲的反冲洗方式,当气冲强度为25 L/(s·m2),水冲强度为8 L/(s·m2)时,纤维球滤料积泥量约占滤料质量的4.53%.      

Human geography of New Orleans’ high-lead geochemical setting

Previous soil lead studies in New Orleans focused on the geochemical footprint and its health impacts. This study examines the human geography of race, income, and age in pre-Katrina metropolitan New Orleans within the context of lead accumulation in soils. Sample points of soil lead data (n = 5,467) collected in 1998–2000 were mapped in a geographic information system (GIS), binned into 9 ranges, and queried by (1) 2000 Census racial demographic data, (2) 1999 median household income, and (3) 2000 age data. The absolute population generally declines as lead levels increase except at lead levels from 200–400 to 400–1,000 mg/kg when population increases; the African–American population comprises a disproportionate share of this cohort. The high-lead areas occur in the inner city, home to the largest populations of African-Americans in New Orleans. The mean household income curve indicates that lower economic groups are at risk to higher levels of lead. A total of 44,701 children under the age of 5 years, plus 123,579 children aged 5–17, lived in census block groups containing at least one sample point with over 100 mg/kg lead, and these include 23,124 and 64,064 young people, respectively, who live near at least one point over 400 mg/kg. Lead exposure affects a panoply of outcomes that influence the health and welfare of the community. Unless corrected, children are likely to return to the same or, because of lack of lead-safe practices during renovation, even higher exposure risks than before the flooding of New Orleans.     

Efficiency and Concordance of Alternative Methods for Minimizing Opportunity Costs in Conservation Planning

Abstract:  Scarce resources and competing land-use goals necessitate efficient biodiversity conservation. Combining multicriteria analysis with conservation decision-support tools improves efficiency of conservation planning by maximizing outcomes for biodiversity while minimizing opportunity costs to society. An opportunity cost is the benefit that could have been received by taking an alternative course of action (i.e., costs to society of protecting an area for biodiversity rather than developing it for some other use). Although different ways of integrating multiple opportunity costs into conservation planning have been suggested, there have been no tests as to which method is most efficient. We compared the relative efficiency of 3 such procedures ( Faith & Walker [1996] , Sarkar et al. [2004] , and a procedure of our own design) in a systematic conservation-planning framework for the Milne Bay Province of Papua New Guinea. We devised 14 opportunity costs and assigned these to 3 scenarios representing different conservation planning concerns: food security, macro-economic development, and biodiversity persistence. For each scenario, we compared the efficiency of the 3 methods in terms of amount of biodiversity protected relative to total expenditure for each opportunity cost. All 3 methods captured similar amounts of biodiversity, but differed in total cost. Our method had the least overall cost and was therefore most efficient. Nevertheless, there was a high correlation and geographical concordance among all 3 methods, indicating a high degree of spatial overlap. This suggests that choosing an appropriate approach may often depend on contextual factors related to the design of the planning question, rather than efficiency alone.     

发展阻燃型HIPS纳米复合材料的研究

本文运用一步熔融共混法制备了含有十溴联苯醚（DBDPO）或十溴二苯乙烷（DBDPE）和C16改性蒙脱土（MMT）的高抗冲聚苯乙烯（HIPS）复合材料,并采用X射线衍射（XRD）、透射电镜（TEM）、UL 94垂直燃烧和锥型量热等试验手段对其燃烧性能和相态进行了表征.结果标明,DBDPO/E存在时仍可获得具有插层结构的HIPS纳米复合材料.由于十溴和蒙脱土两种体系间的良好协同效应,这些材料的阻燃性提高、燃烧后的热释放速率下降.文中对其潜在机理进行了探讨.这种协同效应可用于指导发展环保性和阻燃性兼顾的HIPS纳米复合材料.     

黄河三角洲二元结构与多元可持续发展初探

黄河三角洲由石油资源的开发而兴起,其区位条件和油气资源条件都十分优越,但目前仍处于经济发达地区的低谷区。通过对二元结构系数的定量分析,发现该地区具有明显的复合二元结构特征,即“油地+城乡”,二元结构是制约三角洲持续发展的一个重要限制性因素。目前,石油产业的全面改组改制、优越的外部环境和自身基础条件、东营港扩建及其附属加工制造业基地的立项、综合性交通运输网络体系的形成等都是三角洲全面发展的难得机遇。要实现多元可持续发展的目标,必须转变观念,由“以油建城”到“以港兴城”、大力发展资源深加工工业和具有竞争优势的制造业;构建高效生态农业经济体系;推进城市的“内聚式”发展。     

低环境负荷型高性能水泥生产技术研究

对水泥生产过程中资源、能源地消耗和对环境的污染等问题进行了分析和研究,并探讨低环境负荷水泥生产技术。研究表明:水泥工业对资源、能源地消耗和环境负荷影响很大,鉴于导致环境负荷的严重性和重要性,根据材料学、热学和环境学等交叉学科入手提出了低环境负荷型水泥生产技术,为水泥工业降低环境负荷和水泥工业可持续发展生产提供新的技术路线或思路。