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41.
Jyri Seppla Matti Melanen Ilmo Menp Sirkka Koskela Jyrki Tenhunen Marja‐Riitta Hiltunen 《Journal of Industrial Ecology》2005,9(4):117-130
The concept of eco-efficiency is commonly referred to as a business link to sustainable development. In this article, ecoefficiency is examined at a regional level as an approach to promoting the competitiveness of economic activities in the Finnish Kymenlaakso region and mitigating their harmful impacts on the environment. The aim is to develop appropriate indicators for monitoring changes in the eco-efficiency of the region. A starting point is to produce indicators for the environmental and economic dimensions of regional development and use them for measuring regional eco-efficiency. The environmental impact indicators are based on a life-cycle assessment method, producing different types of environmental impact indicators: pressure indicators (e.g., emissions of CO2 ), impact category indicators (e.g., CO2 equivalents in the case of climate change), and a total impact indicator (aggregating different impact category indicator results into a single value). Environmental impact indicators based on direct material input, total material input, and total material requirement of the Kymenlaakso region are also assessed. The economic indicators used are the gross domestic product, the value added, and the output of the main economic sectors of Kymenlaakso. In the eco-efficiency assessment, the economic and environmental impact indicators are monitored in the same graph. In a few cases eco-efficiency ratios can also be calculated (the economic indicators are divided by the environmental indicators). Output (= value added + intermediate consumption) is used as an economic indicator related to the environmental impact indicators, which also cover the upstream processes of the region's activities. In the article, we also discuss the strengths and weaknesses of using the different environmental impact indicators. 相似文献
42.
Summary The rate of flow and nitrate and phosphorus content of the water from four drained sandy and clayey plots of size 12×60 m
cropped to continuous corn were determined following two annual applications of different rates (0, 260, 390 and 520 kg N/ha)
of cow manure slurry. The drain flow was directly related to the rainfall and was greatly influenced by soil texture. The
N losses were greater in 1972 (7.8 to 19.1 kg N/ha) than in 1971 (0.4 to 7.8 kg N/ha) because of more summer rainfall. Nitrogen
and phosphorus losses were larger from the sandy plots than from the clayey plots. The manure application rates had no apparent
effect on nitrogen losses in the drain water. 相似文献
43.
The literature pertaining to the use of registered antibacterial agents in Mediterranean finfish farming is reviewed, with
an emphasis on the Greek fish-farming industry. This review provides a scientific resource dedicated to the design of future
antibacterial dosing regimes in Mediterranean fish farming, where insufficient supporting information is currently available.
This paper addresses the paucity in knowledge concerning pharmacokinetics and the efficacy and environmental impact of commonly
used antibacterials needed to direct future research and promote good practices in the euryhaline fish farming industry. Several
registered antibacterials are currently available for combating bacterial infections, including tetracyclines, (fluoro) quinolones,
potentiated sulfa, penicillin and chloramphenicol derivatives. Based on the available data, oxytetracycline (OTC) and quinolone
drugs (oxolinic acid – OA and flumequine – FLU) are the most widely used in Mediterranean aquaculture. As a result these drugs
have received the most extensive studies, whereas, there is considerable paucity of reliable data on pharmacokinetic and the
depletion characteristics of other drugs used, particularly potentiated sulfa, penicillin derivatives and florfenicol. We
find there is incomplete data on drug efficacy and minimum inhibitory concentrations (MIC) for common antibacterials used
against the major bacterial pathogens of Mediterranean fish species. Furthermore, a considerable lack of data on environmental
drug concentrations around Mediterranean fish farms was also identified, highlighting the need for more extensive environmental
studies to monitor contamination in environmental components i.e., water and sediment, and in non-target species (flora and
fauna). Prudent selection and use of antibacterials can encourage lower dosage applications, enhance treatment efficacy, and
help to minimize contamination of the environment. Selection of readily bioavailable drugs which have low environmental persistence,
low aquatic toxicity and high antibacterial efficacy is advised, to reduce potential losses to the environment and associated
toxic effects on target species and the development of bacterial resistance. Lack of present data made it impossible to provide
thorough and accurate guidance on selection and use of antibacterials and approaches for minimizing environmental impacts
for the treatment of major euryhaline aquaculture species. 相似文献
44.
Aquatic environmental impact associated with stream-crossing by a pipeline was monitored at Archibald Creek, B.C. for two years. Water chemistry and benthic macroinvertebrates were used as monitoring tools. Results indicated that impacts arising from stream-crossing were short-term and non-residual.Funded by a contract from Canadian Arctic Gas Study Limited, calgary, to Aquatic Environments Limited, Calgary.Aquatic Environments Limited, Calgary.Aquatic Environments Limited, Calgary. 相似文献
45.
46.
As zoos have sought to further their conservation missions, they have become powerful providers of environmental education. Outside of “formal” education initiatives, such as those designed for school and other organized groups, or structured public talks programmes, much of the learning potential that the zoo has to offer is around the viewing of animals and the response of visitors to them. In this, zoo learning is a very personal construct, develops from the previous knowledge, and experiences and motivations of each individual. In this article, we make the assertion that learning potential, although difficult to quantify, is very much related to the attractiveness of animal species and the interest that visitors show in them. Using standard behaviorist measures of attraction and interest (the proportion of visitors that stop and for how long), we analyzed the relative interest in 40 zoo species held in a modern UK zoo and the variables that are significant in predicting that popularity. Further to this, the suggestion is made that the zoo collection planning process could use such information to make more informed decisions about which species should be housed for their educational value. Taxonomic grouping was found to be the most significant predictor of visitor interest—that is, visitors were far more interested in mammals than any other group—although body size (length), increasing animal activity and whether the species was the primary or “flagship” species in an exhibit or not, were all found to have a significant bearing on visitor interest. Zoo Biol 29:715–731, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
47.
Slavco Mitev Suzana Dinevska-Kovkarovska Biljana Miova 《Journal of thermal biology》2005,30(8):563-568
(1) Changes in the activity of hepatic glycogen phosphorylase a+b and a (GPh-ase a+b and a), liver glycogen content and blood glucose level during acclimation to moderate high environmental temperature (35±1 °C) were studied. (2) Experiments were carried out on adult fed Wistar rats of both sexes, previously given either short-term (1, 4 and 7 days) or long-term (14, 21, 30 and 60 days) exposure to high environmental temperature. The controls were continuously kept at room temperature (20±2 °C). (3) The results obtained showed that in the period of short-term exposure the liver glycogen content was decreased significantly (after the first and fourth days in male rats and after first day in female rats) and the GPh-ase a activity increased (after first day in male rats and after first, fourth and seventh day in female rats). Long-term exposure caused significant increased liver glycogen content (beginning from the 14th day in male rats and the 21st day in female rats) until the end of the acclimation period (60 days). The elevated activity of GPh-ase a persists after 14th day of exposure only in female rats while there are no significant changes over the rest of the acclimation period in both sexes. There were no significant changes in total GPh-ase activity during the whole period of exposure. Blood glucose level was significantly decreased throughout the whole period of acclimation to high environmental temperature, in both sexes (except in the 1 day exposed groups). (4) The increased activity of hepatic GPh-ase a and decreased glycogen content suggested that the short-term exposure to heat stimulates the glycogenolytical processes. Decreased blood glucose level, and elevated liver glycogen content (r=-0.7467 in male and r=-0.6548 in female rats) suggested that prolonged exposure to high environmental temperature stimulated glycogenogenesis, without changes in the GPh-ase activity. 相似文献
48.
本文就粗品肝素钠生产的原料控制硬件设施管理和环保等方面进行了论述,介绍了一些改进的方法和措施,并就该方面的的一些问题进行了探讨,提出了解决的方法。 相似文献
49.
I. S. Zvyagintseva E. G. Surovtseva M. N. Poglazova V. S. Ivoilov S. S. Belyaev 《Microbiology》2001,70(3):270-276
Gas liquid chromatography (GLC) was used for the first time to screen for machine oil–degrading microorganisms. Oil degradation was evaluated from the microorganism respiratory activity during the utilization of oil as the sole carbon and energy source. The results are consistent with those obtained by the conventional weighing method. Substrate specificity of the active strains with respect to different machine oils was studied. Bacterial communities exhibited the highest activity, whereas a Rhodococcus erythropolisstrain was the most active among pure cultures. Various stages of bacterial interaction with oil drops were followed by means of fluorescent microscopy. 相似文献
50.
WILLIAM H. CLEMENTS MARJORIE L. BROOKS† DONNA R. KASHIAN‡ ROBERT E. ZUELLIG§ 《Global Change Biology》2008,14(9):2201-2214
Changes in regional climate in the Rocky Mountains over the next 100 years are expected to have significant effects on biogeochemical cycles and hydrological processes. In particular, decreased discharge and lower stream depth during summer when ultraviolet radiation (UVR) is the highest combined with greater photo-oxidation of dissolved organic materials (DOM) will significantly increase exposure of benthic communities to UVR. Communities in many Rocky Mountain streams are simultaneously exposed to elevated metals from abandoned mines, the toxicity and bioavailability of which are also determined by DOM. We integrated field surveys of 19 streams (21 sites) along a gradient of metal contamination with microcosm and field experiments conducted in Colorado, USA, and New Zealand to investigate the influence of DOM on bioavailability of heavy metals and exposure of benthic communities to UVR. Spatial and seasonal variation in DOM were closely related to stream discharge and significantly influenced heavy metal uptake in benthic organisms. Qualitative and quantitative changes in DOM resulting from exposure to sunlight increased UV-B (290–320 nm) penetration and toxicity of heavy metals. Results of microcosm experiments showed that benthic communities from a metal-polluted stream were tolerant of metals, but were more sensitive to UV-B than communities from a reference stream. We speculate that the greater sensitivity of these communities to UV-B resulted from costs associated with metal tolerance. Exclusion of UVR from 12 separate Colorado streams and from outdoor stream microcosms in New Zealand increased the abundance of benthic organisms (mayflies, stoneflies, and caddisflies) by 18% and 54%, respectively. Our findings demonstrate the importance of considering changes in regional climate and UV-B exposure when assessing the effects of local anthropogenic stressors. 相似文献