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631.
清洁生产审计废物评估县企业进行清洁生产审计工作的技术关键,本文提出的评估技术方法的主要内容是,对审计重点进行总物料平衡和水总量平衡的实测。进行废物起因分析和废物排放量分析。利用该技术方法,对化纤印花生产示范实例进行了清洁生产审计评估和分析。 相似文献
632.
火电厂生态工业园评价指标体系研究 总被引:6,自引:1,他引:6
建立了火电厂生态工业园评价指标体系,运用层次分析法确定了指标体系中各指标的权重,建立了火电厂生态工业园模糊综合评价模型,确定了火电厂生态工业园综合评价的程序和方法,并将这一模型应用于包头铝电生态工业园。 相似文献
633.
Marianne Schwartz Ph.D. David N. Cooper David S. Millart Vijay V. Kakkar Elma Scheibel 《黑龙江环境通报》1992,12(11):861-866
A novel mutation was detected in the Factor VIII gene of a sporadic case of severe haemophilia A. The lesion, a CGA → TGA transition, converts Arg 795 to Term and adequately accounts for the severe phenotype observed. PCR/direct sequencing was used to confirm the carrier status in the mother. Exclusion of haemophilia A in an at-risk pregnancy was then achieved by demonstration of the absence of this lesion in fetal DNA from a chorionic villus sample. The mutation was also detectable by chemical cleavage of mismatch (CCM), which both confirmed the prenatal diagnosis and established the carrier status of the proband's sister. This example therefore serves to illustrate the potential of direct gene analysis in sporadic cases of haemophilia A and/or in families uninformative for known RFLPs. 相似文献
634.
635.
本研究在着力改善生态环境和调整产业空间布局的背景下,着眼于国民经济行业中高能耗、高污染的污染密集型产业,基于2000—2015年中国30个省区的面板数据,在污染密集型产业识别的基础上,考察了污染密集型产业集聚和环境污染的空间特征,构建了空间面板杜宾模型,并从空间溢出视角,探讨了污染密集型产业集聚的环境效应.研究发现:①污染密集型产业集聚和环境污染均具有显著的空间正相关性;②污染密集型产业集聚和环境污染之间存在显著的倒"U"型曲线关系,对于产业集聚水平较高的山西、宁夏和内蒙古,有望通过空间溢出效应和政策干预发挥减排效应,其他省区集聚水平的提高将会加剧环境污染;③经济发展水平和外商直接投资与环境污染之间均具有显著的正相关关系,而技术创新能力的提高能显著降低污染水平. 相似文献
636.
分析了不同品种的再生浆造纸工艺及给排水流程 ;采用锅炉烟气处理脱墨黑液 ,漂白废水用于废水脱色 ;采用絮凝沉淀、过滤与化学处理相结合的方法处理综合污水。实现废水多级回用 ,循环水率达 80 %~ 90 % ,少量废水达标排放 ,投资和运行费用可节省近 5 0 %。 相似文献
637.
针对旧工业建筑再生利用项目施工过程中存在诸多安全隐患的问题,首先,结合此类项目遗留工业垃圾冗杂、施工场地狭窄、部分构件拆换、大型机械使用受限的施工特点从4MTE角度构建施工安全评价指标体系。然后,在考虑指标赋权的主客观综合性与评价工作的未确知性后,建立了基于结构熵权法与未确知测度理论的旧工业建筑再生利用项目施工安全评价模型,并通过工程实例验证该模型,得出的评价结果与实际情况相符。最后,结合未确知测度单因素指标测度函数的特点,提出了施工安全管理改进策略的制定方法。 相似文献
638.
Over the last decade, adaptive co‐management has been recommended as a policy framework to address complex and uncertain resources management issues. Implementing this theoretical management concept requires the integration of multidisciplinary research and local knowledge. Yet practical protocols to link science, policymaking and societies have yet to be developed. We designed a protocol to produce legitimate, credible and relevant solutions to a regional resources management issue. This is a two‐component protocol. A stakeholder grid categorizes stakeholder representatives in three distinct specialized dialogue arenas: institution representatives, technical experts and local end‐users. An iterative co‐design process then builds on these arenas to assess the institutional legitimacy, technical credibility and empirical relevance dimensions of a common solution initiated by an initial plausible promise. We tested this framework in Réunion to address organic waste management issues at the regional level. The plausible solution explored was the introduction of a recycling industry involved in collecting organic waste and producing and selling organic fertilizers tailored for local crop systems. The protocol application outcomes were consolidated and documented scenarios accepted by all, with knowledge exchange and the broad spread of a stabilized expectation contributing to private initiatives and public policy change. 相似文献
639.
Road Erosion and Delivery Index (READI): A Model for Evaluating Unpaved Road Erosion and Stream Sediment Delivery 总被引:1,自引:0,他引:1
Lee Benda Cajun James Daniel Miller Kevin Andras 《Journal of the American Water Resources Association》2019,55(2):459-484
The Road Erosion and Delivery Index (READI) is a new geographic information system–based model to assess erosion and delivery of water and sediment from unpaved road networks to streams. READI quantifies the effectiveness of existing road surfacing and drain placements in reducing road sediment delivery and guides upgrades to optimize future reductions. Roads are draped on a digital elevation model and parsed into hydrologically distinct segments. Segments are further divided by engineered drainage structures. For each segment, a kinematic wave approximation generates runoff hydrographs for specified storms, with discharge directly to streams at road–stream crossings and onto overland‐flow plumes at other discharge points. Plumes are attenuated by soil infiltration, which limits their length, with delivery occurring if plumes intersect streams. Sediment production and sediment delivery can be calculated as a relative dimensionless index. READI predicts only a small proportion of new drains and new surfacing results in the majority of sediment delivery reductions. The model illustrates how the spatial relationships between road and stream networks, controlled by topography and network geometries, influence patterns of road–stream connectivity. READI was applied in seven northern California basins. The model was also applied in a recent burn area to examine how reduced hillslope infiltration can result in increased hydrologic connectivity and sediment delivery. 相似文献
640.
The deactivation of catalyst is a significant reason for its limited application during the catalytic fast pyrolysis (CFP) process. To reduce the coke formation, binary compound impregnation (BCI) and chemical liquid deposition (CLD) were used to modify HZSM-5 catalysts. At the same time, the self-designed microwave reactor separated the pyrolysis of bamboo and catalytic upgrading of primary vapor, which made the catalytic effect more thorough. Experimental results indicated that CLD used TiO2 deposition to cover external acid sites, while BCI by phosphorus-nickel could cover and partly destroy superficial acid sites through two different ways. Within the scope of the loaded amount studied, the yield of aromatic hydrocarbons in the oil phase increased at first and then decreased, while the coke formation reduced continuously. BTX (benzene, toluene and xylene), the most valuable product in bio-oil, drastically increased by 39.1% and 22.6% respectively over the CLD and BCI modified catalysts. Considering the catalytic performance as well as cost, CLD over HZSM-5 has more advantages in the CFP process to upgrade bio-oil. 相似文献