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61.
Central and Eastern Europe (CEE) is a rapidly changing and developing region which is making the transition to a market based economy. Along with economic reforms, the countries of the region are engaged in substantial environmental reforms, including climate change mitigation activities. Mitigation of, and adaptation to, the consequences of climate change are costly processes. It is therefore of great importance that the national and international mechanisms addressing these problems use methods both environmentally sound and economically efficient. Through two case studies that address the Clean Development Mechanism (CDM) in the Former Yugoslav Republic of Macedonia, and the Green Investment Scheme (GIS) in Romania, this paper explores challenges, related tasks and main problems in the establishment of mechanisms of the Kyoto Protocol in Central and Eastern Europe.  相似文献   
62.
石化装置长周期安全运行风险分析和对策   总被引:3,自引:0,他引:3  
随着国际竞争的激烈,石化生产装置的长周期运行成为我国石化企业的降本增效的主要手段。如何保证本质安全成为长周期运行的难题。本文以延迟焦化装置为例,主要从工艺原理、工艺原则流程和物料性质等方面进行了系统的风险分析,对设备利用英国TISCHUK公司的T-OCA软件进行RBI(Risk-based Inspection,即RBI)评估,确定了装置长周期运行存在的薄弱环节,并提出了控制措施。实践证明,该套方法对我国石化生产装置的长周期安全运行提供了科学的技术支持。  相似文献   
63.
Appropriate land management decisions are important for current and future use of the land to ensure its sustainability. This requires that land management units (LMUs) be specified to enable the identification of specific parameters employed in decision making processes. This paper presents the development of a conceptual model, within geographic information systems (GIS), for defining and assessing LMUs from available biophysical information. The model consists of two main components (sub-models): land quality-based suitability analysis and soil erosion estimation. Using a fuzzy set methodology, the first sub-model was constructed to derive a land suitability index (LSI) for a cropping land utilization type. The LSI thus highlights the suitability grades of every pixel in the study area on a continuous basis. A sub-model of soil erosion was established based on the Revised Universal Soil Loss Equation (RUSLE) utilising the same spatial data bases employed for structuring the LSI. Using a soil loss tolerance principle, a fuzzy membership function of average annual soil loss (called soil loss index, SLI) was established, leading to compatibility between LSI and SLI for data integration. LMUs were then derived from various combinations of LSI and SLI. The methodology developed shows the significance of the model for refining available land suitability evaluation systems, which take no account of expected land degradation (from erosion) due to a nominated land use. It also provides a valuable guideline for cost-effective GIS applications in the identification and assessment of homogeneous land units, using available spatial information sets, at a finer scale.  相似文献   
64.
ABSTRACT: Recent Federal and some State legislation has enlarged the scope of permitted or required actions of local units of government in water resources management and protection. Much of the legislation encourages local units of government to introduce water resources planning measures which will be preventive instead of corrective. Extensive public works measures, environmental destruction and the threat to human life can thus be eliminated or reduced. Research has developed and tested a method for identifying the elements of a water resources protection program for small urbanizing watersheds which was technically adequate and socially acceptable to the communities implementing such programs. Research results suggest that deliberate efforts will be necessary to inform and educate local units of government as to the usefulness of the legislation; and that the program must reflect local natural resource conditions and local preferences for the method of accomplishing the protection. Successful implementation could be restrained by inertia of local units of government, a lack of tradition in such programs, and hostile existing agencies.  相似文献   
65.
In today's society the planned management of groundwater resources has played an increasingly greater role. One means of insuring the protection of groundwater quantity and quality is a regional zoning of groundwater resources. Regional zoning means to classify a given region with regard to hydrogeological characteristics and to evaluate and determine the possible use of each zone. The necessary assumption is the appropriate knowledge of geological structure (compiled in a geological map) and of hydrogeological conditions (compiled in a hydrogeological map). The basis for subdivision is a hydrogeological unit distinguished and delineated on the basis of lithological, stratigraphical, structural, and hydrogeological characteristics. It should have its own distinct hydrological system. The hydrogeological region is the basic unit. Regions may be grouped into larger units: hydrogeological provinces and realms. The subdivision of regions into hydrogeological zones, or subzones when applicable, forms the basis for a groundwater development plan.  相似文献   
66.
Background, Aim and Scope At present, large-scale paper manufacture involves delignification and bleaching by elemental chlorine free (ECF) or totally chlorine free (TCF) processes. The wastewater is purified by secondary treatment (mechanical, chemical and biological) which removes most of the toxic substances from the discharge. However, we found residual toxicity in the high molecular (> 1000 D) matter (HMWM) of the discharge by test of the RET (reverse electronic transfer) inhibition. This fraction consists mainly of polydisperse lignin (LIG) and carbohydrate (CH) macromolecules. Structural units in these molecules are studied by pyrolysis gas chromatography / mass spectrometry (Pyr-GC/MS). In the present work, our aim was to find out those structural units which could explain the RET toxicity of LIG or CH molecules. We compared statistically RET toxicity values of the HMWM samples from treated wastewaters of pilot pulping experiments and intensity variation of the pyrolysis product gas chromatograms of these samples. This application is a novel study procedure. Methods Pyrolysis products (Py-GC/MS results) and inhibition of RET (reverse electronic transport toxicity) as TU50 and TU20 of HMWM (High Molecular Weight Material; Mw > 1000 D) were compared by multivariate statistics. The samples were from laboratory pilot stages of TCF (Totally Chlorine Free) and ECF (Elemental Chlorine Free) manufacture of softwood pulp. Py-GC/MS was done without and with addition of TMAH (Tetra Methyl Ammonium Hydroxide). The name and structure of each abundant fragment compound was identified from its retention time and mass spectrum compared to authentic reference compounds or literature. Four sets of Toxicity Units (TUs) and GC peak areas of the pyrolysis fragments were obtained. The data were normalized by division with LIG (lignin content of each sample). TU values were dependent and the fragment values independent (explanatory) variables in statistical treatments by SPSS system. Separate analyses of correlations, principal components (PCA) and stepwise multiple linear regression (SMLR) were performed from the four sample sets TCF and ECF with and without TMAH. Results and Discussion From the CH fragments, 2-furfural in TCF, and from the LIG fragments, styrene in ECF showed the highest probabilities to originate from source structures of toxicity. Other possible compounds in concern were indicated to be CH fragment 2-methyl-2-cyclopenten-1-one in ECF and LIG fragments 2-methoxy-4-methylphenol, 4,5-dimethoxy-2-methylphenol and 2-methylphenol in TCF.  相似文献   
67.
A cost-efficient way to allocate carbon dioxide (CO2) emission reductions among countries or regions is to harmonise their marginal reduction costs. This could be achieved by a market of emission reduction units (ERUs). To model such a market, we use a multi-regional MARKAL-MACRO model. It gives insights into the consequences of co-ordinating CO2 abatement on regional energy systems and economies. As a numerical application, we assess the establishment of a market of ERUs among three European countries for curbing their CO2 emissions.  相似文献   
68.
气液多相流泵及其在气浮装置中的应用   总被引:3,自引:0,他引:3  
多相流泵可被可用于带气液体、气液混合或气化液体的输送。在污水处理的气浮装置中,通过多相流泵直接溶气和减压射流,气泡直径可小至30μm,气体饱和度可达100%。由此提高了装置处理效果,降低运行费用。文中主要介绍其基本结构和在气浮装置中的应用效果。  相似文献   
69.
With 110-d incubation experiment in laboratory,the responses of microbial quantity,soil enzymatic activity,and bacterial community structure to different amounts of diesel fuel amendments were studied to reveal whether certain biological and biochemical characteristics could serve as reliable indicators of petroleum hydrocarbon contamination in meadow-brown soil,and use these indicators to evaluate the actual ecological impacts of 50-year petroleum-refining wastewater irrigation on soil function in Sbenfu irrigation area.Results showed that amendments of≤1000 mg/kg diesel fuel stimulated the growth of aerobic beterotrophic bacteria,and increased the activity of soil dehydrogenase,hydrogenperoxidase,polypbenol oxidase and substrate-induced respiration.Soil bacterial diversity decreased slightly during the first 15 d of incubation and recovered to the control level on day 30.The significant decrease of the colony forming units of soil actinomyces and filamentous fungi can be taken as the sensitive biological indicators of petroleum contamination when soil was amended with≥5000 mg/kg diesel fuel.The sharp decrease in urease activity was recommended as the most sensitive biochemical indicator of heavy diesel fuel contamination.The shifts in community structure to a community documented by Sphingomonadaceae withinα-subgroup of Proteobacteria could be served as a sensitive and precise indicator of diesel fuel contamination.Based on the results described in this paper,the soil function in Shenfu irrigation area was disturbed to some extent.  相似文献   
70.
举高消防车广泛应用在石油化工装置区火灾中。为高效发挥举高消防车在石油化工装置区火灾中的作用,对石油化工装置区火灾中广泛使用的举高消防车的结构性能进行了分析,针对举高喷射消防车的特点,分析了装置类型、作业场地、安全工作范围、火场热辐射对其在石油化工装置区火灾使用中的影响。分析给出了石油化工装置区火灾中消防通道的要求、举高消防车距离火源的安全距离及其臂架的工作要求,并提出了举高消防车在石油化工装置区火灾中的安全部署要求。研究结果可以为举高消防车在石油化工装置区火灾中的安全部署及作战效能的提高提供技术支持。  相似文献   
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