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991.
992.
The quantitative analysis of glass, ceramics and related silicate systems by means of energy dispersive X-ray fluorescence spectrometry is considered and problems arising from the selective absorption of X-rays in multi-element specimens are discussed. A computer programme written in FORTRAN and based upon a “semi-fundamental parameters” approach to the correction of matrix effects in glass and chemically similar materials is fully described. Model data are provided to enable the programme to be run and tested. An “empirical coefficients” computer programme for the quantitative analysis of silicate systems is outlined and the limitations of this type of programme are pointed out. The importance of adequate sample preparation prior to X-ray spectrometric analysis is stressed.  相似文献   
993.
994.
An environmental assessment of the Canadian Nuclear Fuel Waste Disposal Concept was initiated in 1989. The primary purpose of the assessment is to determine the technical feasibility of burying nuclear-fuel waste deep into the Canadian Shield. If deemed acceptable, a second phase of facility siting will commence. The purpose of this paper is to evaluate the social and political dimensions of nuclear-fuel waste management in Canada. It is contended that nuclear-fuel waste management transcends technical concerns, and that the ultimate success or failure of siting procedures is hinged on social and political acceptability. Data focusing on various facets of a nuclear-fuel waste disposal facility were collected from a sample of residents from three northern Ontario communities. Results demonstrate that there is a strong relationship between facility acceptability, risk perception, and distance from community. On the basis of these findings, it is contended that a regional siting approach needs to be developed and implemented to ensure that concerns over the viability of nuclear power, equity, and trust are incorporated and granted legitimacy in the management of nuclear-fuel waste. Une évaluation environnementale du concept d'élimination des déchets de combustible nucléaire au Canada a débuté en 1989. L'idée première de cette évaluation est de déterminer la faisabilité d'enfouir les déchets de combustible nucléaire dans le Bouclier canadien. Si l'on estime que c'est possible, une deuxième phase dans le choix d'un emplacement d'enfouissement débutera. Le but de cet exposé est d'évaluer les dimensions sociale et politique qu'entraînent la gestion des déchets de combustible nucléaire au Canada. On dit que la gestion des déchets de combustible nucléaire va au-delà des préoccupations techniques et que le succès ou l'échec des procédures de choix d'emplacement dépendent aussi de l'acceptabilité sociale et politique. Les données portant sur différentes facettes d'élimination des déchets de combustible nucléaire ont été recueillies auprès de résidents sélectionnés dans trois communautés du nord de l'Ontario. Les résultats ont montré qu'il existait un lien très fort entre l'acceptabilité des installations, la perception de risque qu'elles entraînaient et la distance qui les en séparait de la communauté. Sur la base de ces constatations, on a avancé, quant au choix d'un emplacement, qu'il fallait envisager une approche sur le plan régional pour assurer qu'en matière de gestion des déchets de combustible nucléaire, on reconnaisse de manière légitime les préoccupations touchant à la viabilité de cette énergie.  相似文献   
995.
996.
Reviews     
Shicite Islam: Polity, Ideology, and Creed , Yann Richard, trans. Antonia Nevill, Oxford, U.K. and Cambridge, U.S.A.: Blackwell, 1995, pp. 217, chronology, glossary, bibliography, index.

Mongols and Mamluks: The Mamluk‐Ilkhanid War, 1260–1281 , Reuven Amitai‐Preiss, Cambridge: Cambridge University Press, 1995, xv + 272 pp.

The Bukharans: A Dynastic, Diplomatic and Commercial History 1550–1702 , Audrey Burton, Richmond, Surrey: Curzon Press, 1997, 664 pp.

Cahiers d'Asie Centrale, No. 1/2 (1996): Inde‐Asie centrale. Routes du commerce et des idées , Tashkent: l'Institut Français d'études sur l'Asie centrale/Aix‐en‐Provence: Editions Edisud, 1996, 366 pp.

The Diary of H.M. Shah of Persia during his tour through Europe in A.D. 1873 , trans. from the Persian by J.W. Redhouse, London, 1874, reprinted 1995, with a new introduction by Carole Hillenbrand, Bibliotheca Iranica. Reprint Series No. 2, Mazda Publishers, Costa Mesa, Calif., [xvi] + xi + 427 pp.

Presse und Öffentlichkeit im Nahen Osten , Christoph Herzog, Raoul Motika, and Anja Pistor‐Hatam, eds., Heidelberg: Heidelberger Orientverlag, 1995, viii + 183 pp.

The Army and the Creation of the Pahlavi State in Iran, 1910–1956 , Stephanie Cronin, London: Tauris Academic Studies, 1997, 296 pp., 3 appendices.

The Republic of Armenia, Volume III: From London to Sèvres, February‐August, 1920; Volume IV: Between Crescent and Sickle: Partition and Sovietization , Richard Hovannisian, Berkeley: University of California Press, 1996, xx + 534 pp., xii + 496 pp.

Majlis va Intikhabat: az Mashrūtah ta Payan‐i Qajar , Mansoureh Ettehadieh (Nezam‐Mafi), Tehran: Nashr‐i Tarikh‐i Iran, 1375/1996–97, 368 pp.

L'Iran au XXe siècle , Jean‐Pierre Digard, Bernard Hourcade, Yann Richard, Paris: Fayard, 1996, 459 pp.

The Shicis of Iraq , Yitzhak Nakash, Princeton: Princeton University Press, 1994, xiv + 312 pp., cloth and paperback.

Debating Religion and Politics in Iran: The Political Thought of Abdolkarim Sorush , Valla Vakili, New York, N.Y.: Studies Department, Occasional Paper Series, no. 2, The Council on Foreign Relations, Inc., 1996, 56 pp.

Tanker Wars: The Assault on Merchant Shipping during the Iran‐Iraq Conflict, 1980–1988 , Martin S. Navias and E. R. Horton, London and New York: I.B. Tauris Publishers, 1996, ix + 244 pp., including appendix, notes, index of ships, and general index. Cloth.

The Turbulent Gulf: People, Politics and Power , 2nd ed., Liesl Graz, London and New York: I.B. Tauris Publishers, 1992. 311 pp., including notes, appendices, bibliography, and index. Paperback.

The Topkapi Scroll: Geometry and Ornament in Islamic Architecture , Gülru Necipo?lu, with an essay on the geometry of the muqarnas by Mohammad al‐Asad, Santa Monica: Getty Center for the History of Art and the Humanities, 1995, xiii + 395, plates, plan, bibliography, index, $160.00.

Techniques et ressources en Iran du 7e au 19e siècle , Parviz Mohebbi, Tehran: Institut Français de Recherche en Iran, 1996.

Suppressed Persian: An Anthology of Forbidden Literature , Paul Sprachman, Costa Mesa, Calif.: Mazda Publishers, lviii + 111 pp., $29.95.  相似文献   

997.
The provision of adequate primary health care in developing countries is often troublesome. The problem is to provide a sufficient number of facilities to be geographically accessible, yet few enough to be properly stocked and staffed. In many less developed countries accessibility problems are exacerbated by extensive rainy seasons in which travel is only possible on paved roads. Using the covering tour model we investigate the use of mobile facilities to resolve this dilemma in Suhum District, Ghana. The model minimizes a mobile facility's travel while serving all population centers within range of a feasible stop. Computational results show that in the rainy season the model cannot provide full coverage; over six percent of the population is beyond a covering distance of eight kilometers. In the dry season, 99 percent of the population can be served by a tour at a covering distance of seven kilometers.Beyond a distance of four kilometers, the dry season problem becomes a trade-off between the distance traveled by healthcare patrons and mobile facilities. These results illustrate the importance of flexibility of mobile systems: if accessibility cannot be provided in all seasons it may still be provided at favorable times of the year.  相似文献   
998.
999.
1000.
The coverage provided by the existing solar radiation monitoring network for British Columbia and adjacent areas in western Canada is assessed and found to be inadequate. It is generally advantageous to use a numerical solar radiation model at available sites to augment the observed values, although this is not a complete solution to the problem. It is also shown that the ability to extrapolate solar radiation data from measurement and modelling locations is strongly determined by the general nature of the synoptic weather conditions. In addition, the use of solar radiation extrapolations is restricted by problems involving homogeneity and isotropy assumptions.
Les auteurs presentent une evaluation de la distribution des stations en Colombie britannique et les aires adjacents du Canada de I'ouest mesurant la radiation solaire; ils en concluent que le reseau actuel est inadequat. 11s soulignent I'avantage d'emprunter un modele numerique pour caracteriser la radiation solaire aux sites disponibles, afin d'aug-menter les donnees observees. Neanmoins, cela ne represente pas pour les auteurs une solution complete du probleme. 11s demontrent que le caractere general des conditions meteorologiques synoptiques determine fortement la possibilite d'une extrapolation de la distribution de la radiation solaire, derivee des donnees mesurees et des modeles adoptes aux sites specifiques. Finalement, ils etablissent que certains problemes concernant les hypo-theses d'homogeneite et d'isotropie imposent leur tour des limites a I'utilite de la methoded'extrapolation pour decrire la radiation solaire.  相似文献   
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