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111.
112.
We use line integral theory to lay out in a more general theoretical framework the conditions under which it is possible to measure with market data the welfare effects of a change in a nonmarket good. We present in detail a numerical method of measuring the value of nonmarket goods using market data, under either weak neutrality or weak complementarity. Our numerical method is more flexible than the existing analytical method because it can be used with any well-behaved Marshallian demand function, and can be used even when the willig condition does not hold. 相似文献
113.
114.
An assessment of hydrocarbon and metal/metalloids (arsenic, cadmium, copper, lead, mercury, selenium, zinc) contamination in sediments from Lake Mulwala, Australia, was undertaken. The objectives of the study were: (i) to determine the extent of contamination in the lake sediments, compared to Australian and international sediment quality guidelines, and (ii) to attempt to identify the contaminant sources to the lake. With the exception of a few samples containing elevated levels of arsenic and/or mercury, the levels of all contaminants in the sediment samples taken from the lake were below the ‘lower trigger’ of the Australian Sediment Quality Guidelines that would warrant further investigation. High molecular weight hydrocarbons (up to 700 mg kg−1) were found in most sediment samples. Non‐metric statistical analysis indicated that the contaminant distribution was different in different parts of the lake, with the lowest concentrations generally found at the influent to the lake. No definitive source(s) of contamination could be identified for either metalloids or hydrocarbons. 相似文献
115.
Fouling is a major problem in membrane processes of water treatment. It can be caused by the deposition of inorganic and organic particulate material, and of microbial cells which may subsequently form biofilms. In practice, usually more than one foulant participates in the formation of membrane deposits. Knowledge of the composition of fouling layers is important for the development of appropriate countermeasures. For this purpose, an experimental system was established for the generation and microscopic visualisation of mixed deposits, using fluorescently labelled model foulants: (i) drinking-water bacteria stained with nucleic acid-specific dyes (biofouling), (ii) synthetic clay mineral laponite stained with rhodamine 6G (inorganic particle fouling), and (iii) fluorescently labelled polystyrene microspheres (organic particle fouling). Polycarbonate and polyethersulfone membranes were challenged with these foulants by dead-end filtration. On the basis of different fluorescent labels, the single foulants in these mixed deposits could be visualised separately by confocal laser scanning microscopy which, in combination with image analysis, allowed the generation of three-dimensional views of the complete deposits. This method offers the possibility for the estimation of quantitative surface coverage by foulants and for the determination of the efficacy of cleaning measures with respect to the removal of different foulants. 相似文献
116.
Manipulating uncertainty 总被引:1,自引:1,他引:0
A. S. Pinto Barbosa 《Constitutional Political Economy》1994,5(3):255-271
Uncertainty about the distributional incidence of policy reforms may, if it impinges selectively on particular subsets of
voters, alter the direction of the majority vote. This possibility should be a matter of special concern when subject to potential
manipulation by a purposeful agent such as a Leviathan-like bureaucracy. This paper discusses a constitutional defense against
such prospect.
This paper was prepared for a conference on “Constitutional Status Quo and Prospects for Change” held at George Mason University
in April, 1994. I am grateful to participants in that conference and to my colleagues at Nova, especially to Mário Páscoa,
for their comments and criticisms. I also benefited from comments of an anonymous referee. Responsibility for errors remains
with me. 相似文献
117.
The notion that prices impound a wide array of information, including market expectations, has led to earnings forecast models conditioned on prices. Yet, presumably, analysts' forecasts capture both public information and certain private information not previously impounded in prices. Accordingly, price-based models are seemingly an inefficient, and less effective, source of expecta-tions. This article investigates this hypothesis using financial analysts', price-based, and naive forecasts. Results indicate that analysts' forecasts (1) are at least as accurate as price-based and naive models, and (2) yield better expectations for market tests relating returns and earnings. These inferences are robust across different information environments. The evidence suggests that analysts either possess private information or are more effective information processors, or both. 相似文献
118.
119.
NOMENCLATUREc radialclearanceh filmthickness h dimensionlessfilmthickness (h/c)L/D ratiooflengthtodiameterp film pressuree eccentri 相似文献
120.
The recent revival of interest in the issue of limiting auditors' liability raises questions about the potential effect of such a limitation on auditors' performance. This paper considers the consequences of limited liability from the perspectives of contracting theory and economic arguments. We examine the potential effect of a reduction in auditors' liability on the standard of care or quality of service they provide, emphasising the "calculus of negligence" concept used by Australian courts. We consider the potential impact of reduced liability on the auditor's decision to shirk responsibilities (the moral hazard problem) and on the value placed on audit services. The analysis shows that placing a statutory cap on auditors' liability has the potential to reduce the effectiveness of bonding mechanisms; provide an avenue for divergent behaviour; lower the level of care provided by auditors; and decrease the value of audit services. 相似文献