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361.
目前生态影响评价研究中的评价对象、内容和方法缺乏统一的模式,本文以攀枝花高耗能园区的开发为例,尝试建立一套系统的工业园区开发生态影响评价方法,该方法以层次分析法为基础,将生态系统分解为经济发展、社会进步、环境保护、景观生态保护四个目标子系统,并在此基础上细化评价因子,通过专家打分和矩阵运算确定其权重,再根据适当的评价标准,运用指数法得出评价结果。结果表明该工业园区在建成前后,其生态综合指数由0.552提高到0.794.其级别由三级提高到二级,说明该园区生态系统总的状态得到改善,该工业园区项目开发可行。  相似文献   
362.
抚顺石化分公司石油三厂原有硫磺回收装置的处理能力已经不能满足生产的需要,2002年对硫磺回收装置进行了扩建和改造。该装置采用了一段高温转化、二级催化转化的克劳斯工艺,采用揝SR敾乖?吸收工艺处理尾气。扩能改造后,新增的尾气处理能力与硫磺回收能力相配套,排放的废气符合国家现行的环保标准。该装置工艺路线合理、可靠,硫回收率高。  相似文献   
363.
Developments in biotechnology and genomics have moved the issue of patenting scientific and technological inventions toward the center of interest. In particular, the patentability of genes of plants, animals, or humans and of genetically modified (parts of) living organisms has been discussed, and questioned, from various normative perspectives. This paper aims to contribute to this debate. For this purpose, it first explains a number of relevant aspects of the theory and practice of patenting. The focus is on a special and increasingly significant type of patents, namely product patents. The paper provides three general arguments against the concept and practice of product patenting. The first argument briefly considers the claim that patents are legitimate because they promote socially useful innovation. Against this claim, it is argued that product patents may hamper rather than promote such innovation. The second and main argument concludes that product patents are not adequately based on actual technological inventions, as they should be according to the usual criteria of patentability. The principal moral issue is that product patents tend to reward patentees for inventions they have not really made available. The final argument proposes a method for patenting the heat of the sun. Assuming that granting this patent will be generally considered absurd, the argument exposes a further, fundamental problem of the concept and practice of product patenting.  相似文献   
364.
Environmental assessment of supercritical water oxidation of sewage sludge   总被引:1,自引:0,他引:1  
Environmental aspects of using supercritical water oxidation (SCWO) to treat sewage sludge were studied using a life cycle assessment (LCA) methodology. The system studied is the first commercial scale SCWO plant for sewage sludge in the world, treating sludge from the municipal wastewater treatment facility in Harlingen, TX, USA. The environmental impacts were evaluated using three specific environmental attributes: global warming potential (GWP), photo-oxidant creation potential (POCP) and resource depletion; as well as two single point indicators: EPS2000 and EcoIndicator99. The LCA results show that for the described process, gas-fired preheating of the sludge is the major contributor to environmental impacts, and emissions from generating electricity for pumping and for oxygen production are also important. Overall, SCWO processing of undigested sewage sludge is an environmentally attractive technology, particularly when heat is recovered from the process. Energy-conserving measures and recovery of excess oxygen from the SCWO process should be considered for improving the sustainability potential.  相似文献   
365.
ABSTRACT: This paper studies the effectiveness of alternative farm management strategies at improving water quality to meet Total Maximum Daily Loads (TMDLs) in agricultural watersheds. A spatial process model was calibrated using monthly flow, sediment, and phosphorus (P) losses (1994 to 1996) from Sand Creek watershed in south‐central Minnesota. Statistical evaluation of predicted and observed data gave r2 coefficients of 0.75, 0.69, and 0.49 for flow (average 4.1 m3/s), sediment load (average 0.44 ton/ha), and phosphorus load (average 0.97 kg/ha), respectively. The calibrated model was used to evaluate the effects of conservation tillage, conversion of crop land to pasture, and changes in phosphorus fertilizer application rate on pollutant loads. TMDLs were developed for sediment and P losses based on existing water quality standards and guidelines. Observed annual sediment and P losses exceeded these TMDLs by 59 percent and 83 percent, respectively. A combination of increased conservation tillage, reduced application rates of phosphorus fertilizer, and conversion of crop land to pasture could reduce sediment and phosphorus loads by 23 percent and 20 percent of existing loads, respectively. These reductions are much less than needed to meet TMDLs, suggesting that control of sediment using buffer strips and control of point sources of phosphorus are needed for the remaining reductions.  相似文献   
366.
ABSTRACT: The objective of this study was to examine the chemistry of Coalbed Methane (CBM) discharge water reacting with semi‐arid ephemeral stream channels in the Powder River Basin, Wyoming. The study area consisted of two ephemeral streams: Burger Draw and Sue Draw. These streams are tributaries to the perennial Powder River. Samples were collected bimonthly from three CBM discharge points and seven channel locations in Burger Draw and Sue Draw. Samples were also collected bimonthly from the Powder River above and below the confluence of Burger Draw. Before sample collection, the pH and electrical conductivity (EC) were measured in the field. Samples were transported to the laboratory and analyzed for alkalinity, major cations, and anions. From the measurement of sodium (Na), calcium (Ca), and magnesium (Mg), practical sodium adsorption ratio (SARp) and true sodium adsorption ratio (SARt) were calculated. Results suggest pH and EC of CBM discharge water was 7.1 and 4.3 dS/m, respectively. The CBM discharge water consisted of higher concentrations of sodium and alkalinity compared to other components. The pH of CBM discharge water increased significantly (p = 0.000) in the downstream channel of Burger Draw from 7.1 to 8.84 before it joined with the Powder River. Dissolved calcium concentration of CBM discharge water decreased significantly (p = 0.000) in the downstream channel water. Subsequently, SARp increased approximately from 24 to 29. The SARt also increased significantly (p = 0.001) in the downstream channel water. For instance, SARt of CBM discharge water increased from 32.93 to 45.5 downstream channels after the confluence of Sue Draw with the Burger Draw. The only significant difference in water chemistry above and below the confluence of Burger Draw with the Powder River was pH, which increased from 8.36 to 8.52. The significant increase in SAR values of CBM discharge water in Burger Draw and Sue Draw tributaries suggest a careful monitoring of salinity and sodicity is needed if CBM discharge water is used for irrigation in semi‐arid environments. Results discussed in this study will be useful to downstream water users who depend on water for irrigation.  相似文献   
367.
ABSTRACT: Surface water impairment by fecal coliform bacteria is a water quality issue of national scope and importance. In Virginia, more than 400 stream and river segments are on the Commonwealth's 2002 303(d) list because of fecal coliform impairment. Total maximum daily loads (TMDLs) will be developed for most of these listed streams and rivers. Information regarding the major fecal coliform sources that impair surface water quality would enhance the development of effective watershed models and improve TMDLs. Bacterial source tracking (BST) is a recently developed technology for identifying the sources of fecal coliform bacteria and it may be helpful in generating improved TMDLs. Bacterial source tracking was performed, watershed models were developed, and TMDLs were prepared for three streams (Accotink Creek, Christians Creek, and Blacks Run) on Virginia's 303(d) list of impaired waters. Quality assurance of the BST work suggests that these data adequately describe the bacteria sources that are impairing these streams. Initial comparison of simulated bacterial sources with the observed BST data indicated that the fecal coliform sources were represented inaccurately in the initial model simulation. Revised model simulations (based on BST data) appeared to provide a better representation of the sources of fecal coliform bacteria in these three streams. The coupled approach of incorporating BST data into the fecal coliform transport model appears to reduce model uncertainty and should result in an improved TMDL.  相似文献   
368.
在对废水中的BOD5进行常规分析时,采用化学稀释法操作繁琐,对稀释倍数估计易发生错误。而利用TraK装置测试样品时,无须进行稀释和化学分析。用该装置对标准样品BOD5的测定结果表明:准确度相对误差为-3.3%~4.3%,精密度的相对误差为-3.5%~5.6%。该仪器测试性能可靠,数据准确度、精密度合格。与化学法对照分析表明,相对误差都在容许范围内,即在可接受范围内。  相似文献   
369.
基于CAN总线的分布式安全报警系统   总被引:4,自引:5,他引:4  
CAN总线是一种多主站局部网络 ,支持分布式控制系统或实时控制系统的通信功能 ,具有检错功能强 ,抗干扰 ,传输速率高等优点 ,广泛应用于工业控制领域。笔者以CAN总线技术为基础 ,用单片机和个人计算机组成分布式安全报警系统 ,该系统具有开放性、全分散体系结构、安装维护简单等特点。笔者介绍了该系统的总体构成及其软件和硬件设计。试验结果表明 ,该系统实现了事故现场、住户与住宅小区三者联系的安全报警功能。系统稳定性好 ,实时性强 ,报警准确。  相似文献   
370.
为了研究实施职业安全健康管理体系(OSHMS)对企业职业安全健康管理状况的影响,对百余家已实施与未实施OSHMS的企业进行了调研,在对调研结果分析研究的基础上,采用双对照分析的方法,对已通过OSHMS认证的企业在建立OSHMS前后的职业安全健康管理状况进行对照比较,以及已建立OSHMS与未建立OSHMS的企业的职业安全健康管理状况进行对照比较,研究结果表明,实施OSHMS有利于提高企业职业安全健康管理的整体水平,改善企业的职业安全健康管理状况,使职业安全健康管理更加科学化和规范化。  相似文献   
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