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This article aims to explore a new approach to assess company decision systems regarding sustainability-related communication and decision support between senior management and product development levels. The assessment approach was developed in theory and its applicability was directly tested in action research in two small and medium-sized companies and two large companies. The results were validated against experiences made by two management consultancies. Our study indicates that successful companies should: (i) integrate sustainability into business goals and plans, backed up by suitable (ii) internal incentives and disincentives and (iii) decision support tools. Our study also indicates that the new assessment approach can be used as a template to assess the current state of sustainability integration in company decision systems.  相似文献   
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The influence of chemical initial conditions and chemical lateral boundary conditions (CLBCs) on long-term regional air quality model simulations was investigated using outputs from an annual simulation of the year 2002 on a North American domain. This simulation was carried out using the AURAMS regional air quality model. It was subdivided into three multi-month segments with two overlap periods (May 15–30 and September 1–30) to allow the segments to be run in parallel. For this approach to work, model predictions had to match very closely by the end of the two-week and four-week overlap periods. The time required for the values of daily domain-average surface PM2.5 concentration to match for the two simulation segments associated with each of the two overlap periods was four and six days, respectively. For individual locations within the model domain, however, the required spin-up period was as much as nine days, considerably longer than the 2–4-day spin-up period usually assumed in the literature. For ozone, on the other hand, the daily domain-average surface ozone concentration values did not converge for either overlap period. A zero-gradient CLBC had been used for all run segments and species. When a time-invariant CLBC for ozone was used instead, the daily domain-average surface ozone concentration values behaved more realistically and did converge after fewer than three days. A similar improvement was also obtained for individual locations, but with spin-up periods of up to nine days. Model chemical spin-up time thus seems to be dependent on the species considered, the time required for the influence of the inflow boundaries to reach all locations within the domain, and the impact of local emissions sources. These results suggest the use of a spin-up period of longer than one week for a large (continental) domain and long-term simulation of PM2.5 and O3 rather than the 2–4 days commonly assumed in the literature.  相似文献   
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Li  Maotian  Finlayson  Brian  Webber  Michael  Barnett  Jon  Webber  Sophie  Rogers  Sarah  Chen  Zhongyuan  Wei  Taoyuan  Chen  Jing  Wu  Xiaodan  Wang  Mark 《Regional Environmental Change》2017,17(4):1153-1161
Regional Environmental Change - Many of the world’s major cities are expected to face significant water shortages in coming decades, largely due to increased demand arising from economic and...  相似文献   
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Water hyacinths are becoming a problem in lakes, ponds and waterways in many parts of the world. This paper contains a literature study of different ways to use water hyacinths, mainly in agricultural or alternative energy systems. The literature review indicated that water hyacinths can be rich in nitrogen, up to 3.2% of DM and have a C/N ratio around 15. The water hyacinth can be used as a substrate for compost or biogas production. The sludge from the biogas process contains almost all of the nutrients of the substrate and can be used as a fertiliser. The use of water hyacinth compost on different crops has resulted in improved yields. The high protein content makes the water hyacinth possible to use as fodder for cows, goats, sheep and chickens. Water hyacinth, due to its abundant growth and high concentrations of nutrients, has a great potential as fertiliser for the nutrient deficient soils of Africa and as feed for livestock. Applying the water hyacinths directly without any other processing than sun drying, seems to be the best alternative in small-scale use due to the relatively small losses of nutrients and workload required. To meet the ever-growing energy demand, biogas production could be one option but it requires investments and technological skills that would impose great problems in developing countries where the water hyacinth is often found. Composting as an alternative treatment has the advantage of a product that is easy to work into the soil compared with dried water hyacinths, because of the decomposed structure. Harvesting and transport of water hyacinths can be conducted manually on a small scale and does not require a new harvesting technique to be introduced. Transporting of fresh water hyacinths means, if used as fertiliser in amounts large enough to enhance or effect crop growth, an unreasonably large labour requirement. Based on the labour need and the limited access to technology, using dried water hyacinths, as green manure is a feasible alternative in many developing countries.  相似文献   
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