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71.
The specific features of formulation and implementation of balance-hydrodynamic simulation during different-scale studies of natural resources of groundwater. Are an example of detailed estimate of the resources and balance of groundwater in the Vologda River basin is given. It is noted that the use of balance-hydrodynamic models, in addition to an increase in the general reliability of estimates, allows the calculation of normal annual characteristics of groundwater resources with different occurrence (exceedance probability), which is impracticable when hydrodynamic methods in other formulations are used. 相似文献
72.
2,4,6-trinitrotoluene transformation by a tropical marine yeast, Yarrowia lipolytica NCIM 3589 总被引:4,自引:0,他引:4
Yarrowia lipolytica NCIM 3589, a tropical marine degrader of hydrocarbons and triglycerides transformed 2,4,6-trinitrotoluene (TNT) very efficiently. Though this yeast could not utilize TNT as the sole carbon or nitrogen source, it was capable of reducing the nitro groups in TNT to aminodinitrotoluene (ADNT). In a complete medium containing glucose and ammonium sulphate as the available carbon and nitrogen sources respectively, the culture was able to completely transform 1 mM (227 ppm) of TNT under such conditions. A dual pathway was found to be functional, one of which resulted in the formation of the hydride-Meisenheimer complex (H(-)TNT) as a transiently accumulating metabolite that was subsequently denitrated to 2,4-dinitrotoluene (2,4-DNT), whereas the other pathway resulted in the formation of amino derivatives. The presence of increasing amounts of reducing equivalents in the form of glucose promoted better growth and the nitroreductases of this yeast to reduce the aromatic ring to 2,4-DNT although, the reduction of the nitro groups to amino groups was the major functional pathway. The ability of this tropical marine yeast to transform TNT into products such as 2,4-DNT which in turn could be metabolized by other microbes has implications in the use of this yeast for bioremediation of TNT polluted marine environments. 相似文献
73.
A. S. Astakhov S. A. Gorbarenko G. A. Bakhareva E. V. Gretskaya V. V. Sattarova 《Lithology and Mineral Resources》2005,40(2):97-113
Results of the study of contents and accumulation rates of Fe, Mn, and a number of trace elements in Upper Quaternary sediments of the Deryugin Basin are presented. Maps of the average contents and accumulation rates of excess Fe, Mn, Zn, Ba, Ni, Pb, Cu, and Mo in sediments of the first oxygen isotope stage (OIS) have been plotted. Anomalous contents and accumulation rates are confined to peripheral zones of the Deryugin sedimentary basin and large fracture zones. Different mechanisms of the influence of fluid-dynamic processes on the rate of hydrogenic and biogenic accumulation of ore elements are assumed.Translated from Litologiya i Poleznye Iskopaemye, No. 2, 2005, pp. 115–132.Original Russian Text Copyright © 2005 by Astakhov, Gorbarenko, Bakhareva, Gretskaya, Sattarova. 相似文献
74.
Summary The paper describes some characteristics of the precipitation patterns in the plain of Friuli-Venezia Giulia. Even if small,
this Region shows a complex rainfall pattern so that, by previous studies, it was divided into four distinct areas with peculiar
pluviometric regimes, namely the Coastal Area, the Plain and Hills Area, the Prealpine Area and the Inner Alpine Area. Nowadays
a new data set, collected by the ERSA/CSA automatic stations, allows to propose a new sub-classification of the Coastal Area
and Plain and Hills Area, under the point of view of the hourly rate of precipitation. This new sub-classification is composed
by five zones: the Coast, the Carso, the Low Plain, the Middle Plain and the Piedmont. Each one of these zones presents a
peculiar seasonal behaviour of the hourly rain-rate.
Received May 31, 1999 Revised September 27, 1999 相似文献
75.
Sébastien Darchen 《Urban geography》2016,37(2):202-222
In this paper, I question whether agglomerations of video game companies in Australia function as clusters (spatially bound) or rather as communities (not spatially bound). The two case studies included in the analysis are the main agglomerations of video companies in Australia—Brisbane and Melbourne. The data have been collected through 21 semi-structured interviews performed between 2012 and 2014. The main findings are as follows: (1) the primary reason that video game companies come together is to share tacit knowledge and skilled labour; (2) these agglomerations do not have the attributes of “creative clusters”; and (3) new technologies enable experienced game developers to operate at the geographic periphery of the main agglomeration of developers. Therefore, to paint a more accurate picture of why some video game companies are successful—beyond simply positive externalities associated with co-localization—I propose the term “networked communities.” This recognizes that social networks at varying scales (local, national, international) are being developed by video game firms in order to thrive and reach a global audience. 相似文献
76.
77.
Astrophysics - Compton scattering of polarized radiation by a nondegenerate and unpolarized electron gas is examined. Two polarization bases are introduced for pulses of photons: external,... 相似文献
78.
S. A. Mouritsen 《International Journal of Earth Sciences》1966,55(3):856-878
Geology must consider the physical processes involved in the genesis of inorganic matter. These processes are ultimately based on cosmogony and cosmology and the associated physics and mathematics of these origins.The approach to genesis impinges on the unknown where a feeling that something finite, and possibly real, exists. The evidence of the unknown must then be compared with the experimental and observed evidence to create a framework from which certain conclusions can be made.The thoughts on genesis and the geological implications are discussed briefly in two parts. Part one includes the basic philosophy, the mathematical and physical concepts; it outlines the philosophy of time, zero and infinity, mass, space, and the mass environments, based on this a ring hypothesis of planetary origins is developed. Part two discusses basic problems of structural geology, fundamental tectonics, the development of continents and continental drift, climatic changes, seismicity, and paleomagnetics.The conclusions drawn from the discussion are: mass ormatter can exist in five states. Continental buttresses are largely made up of rocks of secondary igneous origin. The core of the earth is made of solar (meteoric) material rather than pure nickel-iron. Continents move under differential density forces which ultimately result in a slow twist or rotation of the earth's outer layers about the core. This rotation causes climatic changes and the many paths observed in tracing polar wandering by paleomagnetics.
Zusammenfassung Dieser Aufsatz versucht, fundamentale geologische Grenzprobleme in Beziehung zu bringen mit fundamentaien physikalischen und astronomischen Problemen, die ihrerseits z. T. noch einer Lösung harren.Ausgehend von einer Betrachtung der Herkunft von Masse, Universum und Sonnensystem werden Probleme der Kontinentalgenese, Kontinentalwanderung, hydrostatischer Druck auf und in Kontinenten, Orogenese, Klimaänderungen und Paläomagnetik in geologischer Zeit besprochen.Der Aufsatz besteht aus zwei Teilen, einem physikalischen und einem geologischen, die zu einem gewissen Grade unabhängig voneinander gelesen werden können. Für ein fruchtbares Verstehen ist es aber ratsam, beide Teile zu lesen. Mathematik ist auf das notwendigste beschränkt.Am Ausgangspunkt der Betrachtung steht die Idee von einem fundamentalen (letztlichen) Masse-Medium, da dieses die Grenze der Erkenntnis bildet.
Résumé La géologie doit considérer le processus physique entraîné dans la genèse de matière inorganique. Ce processus est finalement basé sur la cosmogonie et cosmologie, ainsi que la physique associée et mathématiques de ces originesL'approche de la genèse se heurte à l'inconnu où le sentiment de quelque chose de fini et peut-être bien réel existe. L'évidence de l'inconnu doit alors être comparée à l'évidence expérimentale et observée, pour créer une structure de laquelle certaines conclusions peuvent être tirées.Les réflexions sur la genèse et les implications géologiques sont exposées brièvement en deux parties. La première partie comprend la philosophie fondamentale, les idées générales de mathématique et physique; elle esquisse la philosophie du temps, zéro et infini, masse, espace et environnements de la masse; basée là-dessus, une hypothèse en cercle des origines planétaires est développée. La seconde partie expose les problèmes fondamentaux de géologie structurale, tectoniques fondamentales, le développement des continents et le mouvement de ceux-ci, changements de climat, séismicité et paléomagnétiques.Les conclusions tirées de l'exposé sont que masse ou matière peuvent exister dans cinq états. Les contreforts continentaux sont en grande partie formés de roche pyrogène secondaire. Le noyau de la terre est fait de matière solaire (météorique) plutôt que de nickel-fer pur. Les continents se déplacent sous des forces de densité différentielle qui résultent finalement dans une torsion lente ou rotation des couches extérieures de la terre autour du noyau. Cette rotation provoque des changements climatique et les nombreuses voies observées en traçant les écarts polaires par paléomagnétique.
. : , , .相似文献
79.
An algorithm is proposed for calculating a harmonic function equal to the projection of the anomalous magnetic field vector onto the normal field direction from in situ measurements of the anomalous magnetic field modulus (the scalar magnetic anomaly) ΔT, which is a nonharmonic function and is nonlinearly related to the magnetization of anomaly sources. It is shown that the inferred estimates tend to the desired harmonic function if the iterative algorithm converges. The convergence conditions and stability of the process are studied numerically in a wide range of amplitudes of the anomalous field. The results of the modeling simulation demonstrate the efficiency of the proposed algorithm in solving magnetic field interpretation problems often encountered in practice. 相似文献
80.
Davis JA May MD Greenfield BK Fairey R Roberts C Ichikawa G Stoelting MS Becker JS Tjeerdema RS 《Marine pollution bulletin》2002,44(10):1117-1129
In 1997, seven sport fish species were sampled from seven popular fishing areas in San Francisco Bay. Mercury exceeded a human health screening value in 44 of 84 (52%) samples. All collected samples of leopard shark and striped bass exceeded the mercury screening value of 0.23 microg/g wet weight. PCBs exceeded the screening value in 51 of 72 (71%) samples. DDT, chlordane, and dieldrin, had lower numbers of samples above screening values: 16 of 72 (22%) for DDT, 11 of 72 (15%) for chlordanes, and 27 of 72 (37%) for dieldrin. Concentrations of PCBs and other trace organics were highest in white croaker and shiner surfperch, the two species with the highest fat content in their muscle tissue. Fish from one location, Oakland Harbor, had significantly elevated wet weight concentrations of mercury, PCBs, DDTs, and chlordanes compared to other locations. Removal of skin from white croaker fillets reduced lipid concentrations by 27-49% and concentrations of trace organics by 33-40%. 相似文献