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371.
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Highland catchments in tropical regions are frequently subjected to soil erosion and the transport of chemicals downstream. Any drastic changes in land use will increase the severity of these processes of land degradation. A simulation study using GLEAMS (Groundwater Loading Effects of Agricultural Management Systems) was conducted at a catchment presently under tea farming in Cameron Highlands, Malaysia. Soil, water and nutrient transport associated with several alternative land uses was studied. In addition, the effect of a disruptive form of land clearing on soil, water and nutrient losses was also investigated. Modelling with GLEAMS required information from field measurements and observations, laboratory analyses, guide tables, industry records, maps and reports published by soil survey and meteorological departments. The most critical step in simulating soil and water movement using GLEAMS is the identification of a representative flow sequence. In the catchment under study, the representative flow sequence was overland flow–channel 1–channel 2. Input data on soil erodibility, porosity and surface roughness were manipulated to represent various degrees and forms of disturbance to the surface soil layer. For all land uses studied, the highest soil loss was predicted for the overland flow area where slope gradient is high and the soil friable. The variations in soil loss, runoff and nutrient loss between landscape elements and between land uses were consistent with soil erosion features observed in the field. Soil and nutrient losses were substantial for crops such as cabbage that required land shaping activities and frequent ploughing of the soil. Predicted data on enrichment ratio of specific surface (ERSS) are consistent with nutrient enrichment processes in the field and could prove to be useful in studies on chemical transport in highland catchments.  相似文献   
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/ The coastal environment of Kuwait has been under considerable stress since the onset of the oil era in the late 1950s and early 1960s. Oil, sewage, and industrial pollution were believed to be the main environmental problems in the coastal zone. The huge oil spill and destruction caused by the Gulf War further complicated those problems. In this article, the temperature, pH, salinity, and total dissolved sulfide (TDS) of the interstitial water in the intertidal zone and the water content and total organic carbon (TOC) of the intertidal sediment were investigated. The purpose of the study was to understand the effect of the physicochemical characteristics on the intertidal benthic ecology and to identify the level and sources of organic pollution in the intertidal zone. The study results indicated that the prevailing harsh environmental conditions, especially high temperature and salinity, restricted benthic fauna diversity and led to the development of a fragile intertidal ecosystem. The fauna inhabiting the intertidal zone was dominated by a few species probably living at their limit of tolerance. Organic pollution was evident mainly in Sulaibikhat Bay and to a lesser extent in Kuwait City waterfront and Shuaiba coast in the south. The pollution was attributed mainly to land-based sources such as the occasional discharge of raw sewage through stormwater outlets, the direct oil spillage, and industrial effluents from refineries, oil terminals, and petrochemical plants. Quantitative analysis was inconclusive in establishing a significant correlation between the chemistry and composition of the benthic fauna. However, close examination of sites with high TOC and TDS concentrations indicated that the benthic fauna in those sites was showing evidence of degradation. A number of strategies were recommended to ensure protection and sustainable management of the coastal environment.KEY WORDS: Intertidal environment; Pollution; Total organic carbon; Dissolved sulfide; Interstitial water; Benthic fauna  相似文献   
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The literature on routinization of work is both ambiguous and equivocal when its impact on quality of working life is considered. The classical management literature suggests that routinization of work has a positive influence on individual performance and by implication on the quality of working life resulting from the overall prosperity generated. However, more recent literature on job characteristics and job design argues that routinization of work has a negative impact on individual performance as it suppresses creative expression on the job. This paper suggests that these mixed findings are due to an inadequate theoretical grasp of the concept of routinization and presents empirical evidence which attempts to clarify the ambiguity. Data were collected from 1148 nurses working in anglophone hospitals in the greater Montreal area in the form of a field survey questionnaire. The results indicated that nurses who worked routine shifts perceived higher levels of quality of working life compared to those on non-routine shifts. The results also indicated that nurses who experienced high routinization in job content perceived lower levels of quality of working life compared to those nurses who experienced low routinization in job content. Implications of these findings for future research are discussed.  相似文献   
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The present study examined the relationship of shiftwork and department-type with employees' job stress, stressors, work attitudes and behavioral intention. Data were collected by means of a structured questionnaire from nurses (N = 1148) working in eight hospitals in a large, metropolitan city in eastern Canada. One-way ANOVA, MANOVA and two-way ANOVA were used to analyze data. Results generally support the prediction that nurses working on fixed shifts were better off than nurses working on rotating shifts in terms of the dependent variables of the present study. The prediction that nurses working in non-intensive care departments were better off than nurses working in intensive care departments received mixed support at best. A few interaction effects of shiftwork × department-type on dependent variables were also noted. The impact of socio-demographic variables — age, marital status, cultural background (English- versus French-speaking) — on the above relationships were also analyzed. Results are discussed in light of the previous empirical evidence on shiftwork and department-type.  相似文献   
377.
ABSTRACT: This paper examines a rapidly expanding area of water supplies, specifically water reclamation and reuse, and provides a comprehensive planning methodology for developing and evaluating water reuse alternatives. The methodology uses five phases: goal setting, identification of reuse opportunities, development and evaluation of planning alternatives, assessment of water reuse linkages, and making decisions and recommendations. A tool called “input-output modeling” is used in the third phase to present numerical data and choices. The methodology seeks to integrate the hydrologic and socio-economic aspects of water resources planning in the area of study. Water reuse may satisfy some of the increasing demands for water in the world, but water quality, economics, public attitudes, and legal and institutional constraints may impose limits on the extent to which it can be employed. The challenge in planning systems is to maximize the utilization of water reuse in the fact of these constraints. The importance of multidisciplinary collaboration cannot be overemphasized. This paper assesses the potential for water reclamation and reuse in developing countries by considering the relationships among the pertinent technical, social, economic, and environmental parameters. Generally, the planning process for water reuse has focused on specific technological processes, but in order to ensure the efficient transfer of waste water reuse technology into the society, the methodology seeks to provide a conceptual model which integrates the hydrologic and socioeconomic aspects of water resources planning and water reuse within the study area. (KEY WORDS: water reuse; water reclamation; planning; methodology; model; reuse technology; socio-hydrologic systems; socioeconomic systems.)  相似文献   
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The capability of carbon nanotubes (CNTs) to adsorb lead (Pb) in aqueous solution was investigated. Batch mode adsorption experiment was conducted to determine the effects of pH, agitation speed, CNTs dosage and contact time. The removal of Pb(Ⅱ) reached maximum value 85% or 83% at pH 5 or 40 mg/L of CNTs, respectively. Higher correlation coeffcients from Langmuir isotherm model indicates the strong adsorptions of Pb(Ⅱ) on the surface of CNTs (adsorption capacity Xm = 102.04 mg/g). The results indicates tha...  相似文献   
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