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961.
Kazuo Fujita Kunio Watanabe Tri Heru Widarto Bambang Suryobroto 《Primates; journal of primatology》1997,38(3):233-245
A series of work by the first author have demonstrated that many macaque species show a visual preference for the pictures
of their own species when the monkeys actively press a lever to see the pictures. We expanded this study to Sulawesi macaques
kept as a pet by local people with slight modification. All seven species of Sulawesi macaques were passively exposed to a
variety of colored slides of Sulawesi macaques. The experimenter recorded the duration of visual fixation onto the pictures.
Male monkeys of all the seven species clearly watched the pictures of their own species for longer duration than those of
the other species. Such visual preference suggested that the seven Sulawesi macaques discriminate each other species and,
thus, they may not be integrated into fewer number of species. This visual preference may work to prevent overall intergradation
of the Sulawesi macaques who sometimes have hybrid zones only in limited areas. This preference was in general weaker in female
monkeys. In one species,Macaca ochreata, females actively avoided to see the pictures of conspecifics. These results may be related to how female monkeys interact
with other individuals. 相似文献
962.
963.
Sylvie Baltora-Rosset Danielle Marty François-Yves Dupradeau Emmanuel Pauthe Véronique Larreta-Garde Gilles Gacel Jean-Pierre Monti 《International journal of peptide research and therapeutics》1997,4(4-6):391-395
Summary The conformations of thermolysin synthetic substrates in H2O/D2O (9/1) and glycerol-d
5 (5 M) are investigated using two-dimensional nuclear magnetic resonance spectroscopy and molecular modeling. The structures
obtained from molecular modeling and NMR studies are compared. Comparisons of these structures with bound inhibitor in the
active site of thermolysin are also discussed. 相似文献
964.
A model was constructed to estimate cancer risks associated with PM10‐bound polycydic aromatic hydrocarbons (PAHs) from Kuwait oil lakes. The design of the risk model was based on a conceptual “chain of events”; leading from levels of PAH compounds in oil lakes, erosion of oil dust and input into the atmosphere, to contaminant concentration in air, to actual human exposure in residential areas. Uncertainties in the “chain of events”; model were addressed using Monte Carlo techniques. To identify the exposure duration of concern [duration beyond which risk becomes unacceptable (i.e. Risk > 10‐6)], four exposure durations were tested 10, 20, 40, 70 years. 40 years was identified to be the exposure duration of concern based on the 95th percen‐tile of the risk distribution. As a result, the acceptability of risk was specified in terms of a single constraint on the 95th percentile of the risk distribution evaluated after 40 years of exposure: 0 < Risk (40 y)0.95 ≤ 10‐6. Based on this constraint, it was estimated that a removal rate of 217, 793.27 m3/year to be an adequate action for risk management. The northern oil lakes were identified as the lakes of most concern when inhalation exposures are considered. 相似文献
965.
This paper proposes a computer-based method for providing product designers with real-time environmental impact assessment. In this concurrent modeling approach, environmental experts build life-cycle models, define their interfaces, and publish them as distributed objects on the Internet. Traditional designers integrating these objects into their design models have access to the impact assessment methods provided by the environmental expert. In this paradigm, the focus shifts from providing techniques that let non-expert designers perform life-cycle impact assessments to tools that facilitate timely communication and information transfer between designers and appropriate environmental experts. Establishing real-time communication between the product design models and the environmental life-cycle models is the primary focus of this paper. Methods for establishing and maintaining the interaction between life-cycle and product design models are described. A beverage container design example illustrates how this collaborative approach can use environmental and traditional design goals to determine effective tradeoffs between design alternatives. 相似文献
966.
967.
Richard Condit Burney J. Le Boeuf † Patricia A. Morris † Marshall Sylvan ‡ 《Marine Mammal Science》2007,23(4):834-855
Many organisms reproduce in temporary aggregations where estimates of colony size can be made by direct counts. When individuals are not synchronous, however, early breeders depart before the last arrive, so counts underestimate the total breeding population. We present a model describing a colony's census as a function of arrival, breeding tenure, and the correlation between them, and we use it to illustrate how variance in arrival and tenure affect the census. Counts of breeding female northern elephant seals ( Mirounga angustirostris ) from 1975 to 2007 were used to test the model. Four of the model's parameters—population size, mean and variance of arrival date, and the correlation between arrival date and breeding tenure—could be estimated from census data using a Bayesian approach; prior estimates of two other parameters—mean tenure and its variance—had to be used to avoid overparameterization. The model's predictions fit observed censuses well and produced reliable estimates of population size and arrival behavior, showing that the maximum census was 8%–16% below the total number of breeding females. This method could be used for estimating abundance in any asynchronous aggregation, given independent information on one of the defining distributions: arrival, tenure, or departure. 相似文献
968.
Christian Capello Stefanie Hellweg Beat Badertscher Hugo Betschart Konrad Hungerbühler 《Journal of Industrial Ecology》2007,11(4):26-38
Abstract: The software tool ecosolvent is presented that allows for comparative environmental assessment of treatment technologies for specific, user-defined, waste-solvent mixtures. The tool is composed of models for waste-solvent distillation as well as for thermal treatment in hazardous waste-solvent incinerators and cement kilns. It was designed with a tiered structure in order to allow for a high flexibility regarding informational needs. The life-cycle assessment method was used to assess the environmental impact. The applicability of the tool is shown with two case studies from industry. In these case studies, various waste-solvent treatment technologies are compared for two specific waste-solvent mixtures. Potential use of the ecosolvent tool for its role in practical decision making in chemicals industries is illustrated by two case studies of waste-solvent systems. In the ethyl acetate case study, the tool indicates that solvent recovery by distillation is clearly better than incineration of the waste solvent. The results from the methanol case study are less clear-cut. In the subsequent article (part II), the ecosolvent tool will be used to derive general rules of thumb and specific recommendations for 45 important solvents used in chemical industries. Additionally, a framework will be presented that provides quick and easy decision support regarding environmentally optimized waste-solvent management. 相似文献
969.
Abstract: In an article on the role of temporal information in life-cycle assessment in this journal, Field and colleagues argued that frequently it is not the single product but the "fleet" (or cohort) of products that "is the appropriate unit of analysis," and that in focusing on the fleet one "explicitly introduces the notion of time as a critical element of comparative life-cycle assessments. …" Major transitions, such as replacement of one fleet of products by an alternative fleet, correspond to a system in a transient rather than steady state, and explicit consideration of time is central to transient analysis.
One tool increasingly used as part of life-cycle assessment, economic input-output (EIO) analysis, at best deals with time in an implicit fashion. This article illustrates how the sequential interindustry model (SIM), a formulation of the EIOmodel that explicitly represents time, might be utilized in life-cycle assessment. SIM introduces this temporal component by explicitly accounting for the time required by production activities and the resulting sequencing of the inputs. This can be thought of as engineering rather than accounting information. The data demands of such a model are not likely to be met at present or at any time in the near future. Even so, simulation methods and the use of so-called synthetic data have a history of productive use in a number of fields, including the social sciences.
SIM also utilizes the contribution of Joshi on the application of the EIO model to environmental impact and the inclusion of the use as well as the production phases of a product in EIO analysis. The possibility of accounting for discounting of future events, with its impact on decision making, is also briefly discussed. 相似文献
One tool increasingly used as part of life-cycle assessment, economic input-output (EIO) analysis, at best deals with time in an implicit fashion. This article illustrates how the sequential interindustry model (SIM), a formulation of the EIOmodel that explicitly represents time, might be utilized in life-cycle assessment. SIM introduces this temporal component by explicitly accounting for the time required by production activities and the resulting sequencing of the inputs. This can be thought of as engineering rather than accounting information. The data demands of such a model are not likely to be met at present or at any time in the near future. Even so, simulation methods and the use of so-called synthetic data have a history of productive use in a number of fields, including the social sciences.
SIM also utilizes the contribution of Joshi on the application of the EIO model to environmental impact and the inclusion of the use as well as the production phases of a product in EIO analysis. The possibility of accounting for discounting of future events, with its impact on decision making, is also briefly discussed. 相似文献
970.
Life‐cycle assessment (LCA) practitioners build models to quantify resource consumption, environmental releases, and potential environmental and human health impacts of product systems. Most often, practitioners define a model structure, assign a single value to each parameter, and build deterministic models to approximate environmental outcomes. This approach fails to capture the variability and uncertainty inherent in LCA. To make good decisions, decision makers need to understand the uncertainty in and divergence between LCA outcomes for different product systems. Several approaches for conducting LCA under uncertainty have been proposed and implemented. For example, Monte Carlo simulation and fuzzy set theory have been applied in a limited number of LCA studies. These approaches are well understood and are generally accepted in quantitative decision analysis. But they do not guarantee reliable outcomes. A survey of approaches used to incorporate quantitative uncertainty analysis into LCA is presented. The suitability of each approach for providing reliable outcomes and enabling better decisions is discussed. Approaches that may lead to overconfident or unreliable results are discussed and guidance for improving uncertainty analysis in LCA is provided. 相似文献