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31.
Henry W. Herzog Alan M. Schlottmann Donald L. Johnson 《Journal of regional science》1986,26(3):445-459
ABSTRACT. The premise of this paper is that one can discover much about the location determinants of high-technology industry by examining the location (migration) decision of workers with high-technology occupations. A model of the high-technology worker migration decision is developed that permits estimation of worker response to both personal and area characteristics, the latter chosen to mirror location factors often cited by high-technology firms as important for both the attraction and retention of their specialized work force. Logit estimates of this model between 1975 and 1980 are presented. The paper is concluded with a discussion of policy implications. 相似文献
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A Roman wreck, named Plemmirio B[1]i, lies on the rocky talus below the southern cliffs of Capo Murro di Porco, near Costa Bianca del Plemmirio (Penisola della Maddalena), prov. Siracusa, Sicily. The cargo of amphoras and iron bars, relatively well-preserved, is situated between 22 m and 47 m depth. Following brief examinations in 1974–1982, a University of Bristol expedition spent four weeks surveying the site in July-August 1983[2] This paper presents an interim summary of these campaigns; a comprehensive report will be published after completion of excavations at the site[3]. The archaeological deposit at Plemmirio B is characterized by concentrations of fragmented amphoras. There is no direct evidence for the structure of the ship, much of which may have disintegrated during the initial wreck process, but study of the artefact distribution suggests a vessel of fairly large capacity. The amphora consignment (which may have numbered no more than 200) comprised cylindrical African containers, 80% of which were form Africana 2A and 20% Africana 1[4] w. The Africana 2A amphoras had internal resinous linings, and so may have contained a fish product rather than olive oil. Other amphoras exposed on the site were at least one Mauretanian Dressel 30 (Keay type 1) and two possibly intrusive amphoras of unclassified types. Ferrous concretions contained voids (hollow casts) which may once have been about 39 wrought iron bars, of two distinctive shapes. These, and several other concretions of unidentified forms, may represent a consignment of iron originally weighing approximately one tonne. Other finds from the wreck are two cooking pots, a small bowl or cup, a sounding lead, three fragments of tegula rooftiles, and two small stone blocks. One of the cooking pots confirms a date for the wreck based on the amphora association of circa AD 180–250, most likely in the first decade of the 3rd century. The amphora assemblage belongs to an important phase of commerce from North Africa represented by at least 20 known wreck cargoes; however, few of these sites have been scientifically recorded or are as closely dated as Plemmirio B, and the diversity of container types and cargo consignments on this wreck is of particular interest. 相似文献
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Christoph Meinel 《Berichte zur Wissenschaftsgeschichte》1985,8(1):25-45
In its attempt to achieve acknowledgement and support as a true science and academic discipline eighteenth-century chemistry experienced that the traditional distinction between theory and practice, respectively between science and art, was an incriminating heritage and did not longer conform to the way chemists saw themselves. In order to substitute the former, socially judging classification into theoretical science and practical art, J. G. Wallerius from Uppsala coined the term pure and applied chemistry in 1751. The idea behind this new conception was that it ought to be chemistry's research aim and not the kind of work, be it manual or intellectual, which was to decide about its branches and their dignity. The change in orientation which took place during the eighteenth century, and which is symbolized by the new dichotomy “pure and applied”, led towards a revaluation of the utilitarian aspects of chemistry. Its historical roots reach back to a long and fruitful cooperation of, and interaction between chemistry and economy, which was reinforced by the Stahlian tradition in Germany and Scandinavia. Subsequently, it was its strong economic bias that helped chemistry to become institutionalized and accepted as an academic discipline distinct from the medico-pharmaceutical profession. The analysis of this change of attitudes, behaviour and institutional pattern suggests that, at least during the period of institutionalization of this particular discipline, social structures and the intrinsic scientific contents are so tightly interrelated, that any division into “internal”, cognitive developments (facts, theory and subject-matter) and “external” conditions (social context and stategies of institutionalization) would be artificial, since they both constitute the scientific community as a context of argumentation and action. 相似文献
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Many current proposals for policy reform call for the use of economic incentives. The growing application of economic incentives in a number of policy areas necessitates continuing critical examination of the claims for and the criticisms of their use. Early empirical evidence on the implementation of incentive schemes serves to shed light on the validity of some of the supporting and opposing arguments. By continuing the assessment of the viability of economic incentives, this study reveals that incentive alternatives face obstacles to use stemming from implementation problems, but political and philosophical issues pose greater threats. Nevertheless, the use of incentives can best be defended on political and moral grounds. Political resistance can be overcome and incentives can be employed effectively, if incentive schemes are understood as fostering one form of social interaction in a mixed regime. 相似文献
40.
J.L. COURTNEY 《The Canadian geographer》1985,29(1):4-16
Regional air carriers have grown from localized, smallscale operations in the early 1960s to national operations in the 1980s. Their expansion results from an interplay of technology, route networks, and regulation policy. Government policy on regulation first assigned regions in the 1960s and then, in the 1970s, promoted entry to trunk transcontinental routes. The initial concept of the air transport region must therefore be revised, as the role of the regional carriers now approaches that of the trunk carriers. Regulation remains a key determinant of market share, and deregulation could accelerate the convergence of regional and trunk carriers.
Dans les années soixantes, les lignes aériennes régionales n'entreprenaient que des activités locales, à petite échelle. Présentement, ces měmes lignes fonctionnent, de plus en plus, comme sociétes nationales. L'élargissement de ces lignes provient de l'interaction de plusieurs facteurs, en particulier la technologie, les réseaux aériens et la politique du gouvernement. Cette dernière a permis aux lignes régionales de passer, en 1970, d'un rle local à une présence nationale. Par conséquent, le concept original d'une région aérienne doit ětre revisé, puisque le rle de la ligne régionale s'approche de plus en plus de celui de la société nationale. La part du marché de chaque type de société se détermine par la réglementation imposée par le gouvernement, et la déréglementation pourrait accelerer la convergence des rles des sociétés régionales et nationales. 相似文献
Dans les années soixantes, les lignes aériennes régionales n'entreprenaient que des activités locales, à petite échelle. Présentement, ces měmes lignes fonctionnent, de plus en plus, comme sociétes nationales. L'élargissement de ces lignes provient de l'interaction de plusieurs facteurs, en particulier la technologie, les réseaux aériens et la politique du gouvernement. Cette dernière a permis aux lignes régionales de passer, en 1970, d'un rle local à une présence nationale. Par conséquent, le concept original d'une région aérienne doit ětre revisé, puisque le rle de la ligne régionale s'approche de plus en plus de celui de la société nationale. La part du marché de chaque type de société se détermine par la réglementation imposée par le gouvernement, et la déréglementation pourrait accelerer la convergence des rles des sociétés régionales et nationales. 相似文献