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971.
Summary The dynamics of the main processes of energy accumulation and dissipation in the Earth's magnetosphere at various geomagnetic disturbance levels is examined. The results of the relevant calculations are tabulated. The relationships between the energy parameters of the solar wind and the Earth's magnetosphere are analyzed. Some conclusions concerning the field-aligned currents in polar caps, the Joule dissipation of energy and the energy injection into the ring current, the energy releases in the upper ionosphere, etc., are drawn.
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972.
Summary This paper presents a new universal classification of slope movements, destined for the purpose of engineering geological mapping. This classification was compiled after critical evaluation of the classifications used by now, on the basis of the experience gained by systematic study of slope movements in Czechoslovakia.The following 4 types of slope processes are recognized regarding to the geomechanical character and velocity of the movement: creep, sliding, flow and fall. Creep is a geologically long-term movement of non-increasing velocity without well-defined sliding surfaces. Sliding is a slope movement of coherent masses along one or more well-defined shear surfaces. Flow represents slope movements in rocks and soils, analogous to the movements in liquids. Fall is a sudden slope movement; the moving mass loses its coherence and, for a short time, also its contact with the underlying rock.The pictures show the elementary types of movements that are obvious in the European climatic conditions. Graphical representation of dimensions and velocity of the phenomena is included.
Zusammenfassung Die vorgeschlagene Klassifikation geht zurück auf systematische Untersuchungen an Rutschgebieten in der SSR. Sie lehnt sich an die besten gebräuchlichen Klassifikationen an, wobei letztere einer kritischen Beurteilung unterzogen werden. Ziel des neuen Vorschlages ist die Erarbeitung von Kriterien für die ingenieurgeologische Kartierung.Auf Grund des geomechanischen Charakters der Bodenbewegungen werden folgende vier Vorgänge unterschieden: Kriechen — geologisch langandauernde, nicht beschleunigte Bewegungen ohne ausgeprägte Gleitflächen; Gleiten — Hangbewegungen zusammenhängender Massen längs einer oder mehrerer Gleitflächen; Fließen — Hangbewegungen von flüssigkeitsähnlichem Charakter; Fallen — plötzliche Hangbewegungen, wobei die bewegte Masse den inneren Zusammenhang und kurzfristig auch den Kontakt mit dem Liegenden verliert.Die Grundtypen werden an Hand europäischer Beispiele graphisch dargestellt und durch Angaben über Größenordnung der Massen und deren durchschnittliche Geschwindigkeit ergänzt.

Résumé D'après les expériences acquises pendant les études de glissements en Tchécoslovaquie et d'après l'examen critique des classifications employées jusqu'ici, on a recommendé la classification suivante, destinée avant tout au levé de géologie de l'ingénieur.En relation avec le caractère géomécanique des mouvements de pente et de leur vitesse, quatre processus sont distingués: fluage, glissement, écoulement, écroulement. Le fluage — mouvements géologiquement de longue durée, sans accélération et sans surfaces de glissement exprimées. Le glissement — mouvements de pente de masses cohérentes, le long d'une ou de plusieurs surfaces de glissement. L'écoulement — mouvements de pente dans les roches et les sols, analogues aux mouvements dans les liquides. L'écroulement — mouvements de pente soudains, au cours desquelles les masses en mouvement perdent entièrement leur connexion intérieure et, pour un temps aussi, le contact avec le sous-sol.Les exemples sur les figures représentent les types principaux des mouvements courants dans les conditions climatiques de l'Europe. On indique aussi les dimensions et la vitesse moyenne des types individuels.


With 4 Figures  相似文献   
973.
The transient planetary waves in the atmosphere and ionosphere seem to occur in the form of bursts of a couple of waves with limited persistence. To study persistence of planetary wave events in the lower ionosphere, data from two radio paths from Central Europe are used, Luxembourg – Panská Ves (f = 6.09 MHz, f eq = 2.1-2.2 MHz) and Deutschlandfunk – Panská Ves (f = 1539 kHz, f eq = 650-700 kHz). The absorption along the former radio paths is formed very predominantly at altitudes of about 90-100 km, whereas the latter absorption is formed mostly at altitudes of about 85-90 km. The persistence of planetary wave type oscillations is studied in three period bands centred at 5, 10 and 16 days. Waves with period T near 5 days reveal a typical persistence of wave events around 5 cycles. Waves with T = 10 days are less persistent with a typical persistence of 3-4 cycles. The typical persistence of waves T = 16 days is no more than 3 cycles. In terms of number of cycles, the persistence of oscillations evidently decreases with increasing period. On the other hand, in terms of number of days, the persistence seems rather to increase with increasing period.  相似文献   
974.
Résumén

La distribution des fabriques dans un dôme trachytique a été analysée sur la base des orientations préférentielles des cristaux de sanidine. L’orientation préférentielle des plans (010) des cristaux de sanidine a été quantifiée par le calcul du tenseur d’orientation. Le sens de cisaillement a été déterminé à l’aide de relations entre les plans S et C.

Les plans (010) des cristaux de sanidine montrent une fabrique résultant d’un aplatissement dans la partie centrale du dôme et d’un cisaillement simple dans les parties marginales. Les critères de cisaillement montrent le mouvement uni forme de magma trachytique à l’échelle de tout le massif. Nous interprétons la disposition des plans S-C et la répartition des fabriques dans le massif à la superposition de lames successives de magma les unes sur les autres. L’acquisition des fabriques dans le massif est comparée aux expériences en compression uniaxiale le Tullis (1976) et la mise en place des magmas trachytiques est assimilée au mouvement d’un piston dans des conditions de basse pression de confinement et de haute vitesse de déformation pendant le stade d’intrusion précuce. Le gonflement faible a modifié tardivement les fabriques initiales surtout dans la partie de déversement et sommitale.  相似文献   
975.
Summary The coefficient of the gamma-ray absorption Cs 137 investigated in eclogites of the Bohemian Massif varies with fresh samples from0.2477 cm –1 to 0.2804 cm –1 . Symplectite is the main factor decreasing the value of down to0.242 cm –1 . On the contrary, the coefficient increases with the increasing content of clinopyroxene and especially of garnet. The linear dependence of the coefficient on the density may be expressed by the equation =0.0682+0.028.  相似文献   
976.
977.
Summary The reaction is studied of measuring systems of quartz gravity meters to external disturbances. The actual elastic system is approximated by a model of a linear oscillator with one degree of freedom. The appropriate differential equation of motion is solved for some of the typical shapes of determinate and random disturbance input signals. The result represents expressions which describe the time behaviour of the output signals.
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978.
Thermal history modelling based on zircon‐ and apatite fission track and apatite (U–Th)/He data constrain and refine the near‐surface exhumation of the south‐eastern Tauern Window (Penninic units) and neighbouring Austroalpine basement units in the Eastern Alps. Fast exhumation on both sides of the Penninic/Austroalpine boundary coincides with a period of lateral extrusion and tectonic denudation of the Penninic units in Miocene time (22–12 Ma). The jump to older ages occurs within the Austroalpine unit along the Polinik fault, which therefore defines the boundary between the tectonically denuded units and the hangingwall at that time. According to the different (U–Th)/He ages between the Penninic Hochalm‐ and Sonnblick Domes we demonstrate a differential cooling history of these two domes in the latest Miocene and early Pliocene.  相似文献   
979.
The form of visual representation affects both the way in which the visual representation is processed and the effectiveness of this processing. Different forms of visual representation may require the employment of different cognitive strategies in order to solve a particular task; at the same time, the different representations vary as to the extent to which they correspond with an individual’s preferred cognitive style. The present study employed a Navon-type task to learn about the occurrence of global/local bias. The research was based on close interdisciplinary cooperation between the domains of both psychology and cartography. Several different types of tasks were made involving avalanche hazard maps with intrinsic/extrinsic visual representations, each of them employing different types of graphic variables representing the level of avalanche hazard and avalanche hazard uncertainty. The research sample consisted of two groups of participants, each of which was provided with a different form of visual representation of identical geographical data, such that the representations could be regarded as ‘informationally equivalent’. The first phase of the research consisted of two correlation studies, the first involving subjects with a high degree of map literacy (students of cartography) (intrinsic method: N?=?35; extrinsic method: N?=?37). The second study was performed after the results of the first study were analyzed. The second group of participants consisted of subjects with a low expected degree of map literacy (students of psychology; intrinsic method: N?=?35; extrinsic method: N?=?27).The first study revealed a statistically significant moderate correlation between the students’ response times in extrinsic visualization tasks and their response times in a global subtest (r?=?0.384, p?<?0.05); likewise, a statistically significant moderate correlation was found between the students’ response times in intrinsic visualization tasks and their response times in the local subtest (r?=?0.387, p?<?0.05). At the same time, no correlation was found between the students’ performance in the local subtest and their performance in extrinsic visualization tasks, or between their scores in the global subtest and their performance in intrinsic visualization tasks. The second correlation study did not confirm the results of the first correlation study (intrinsic visualization/‘small figures test’: r?=?0.221; extrinsic visualization/‘large figures test’: r?=?0.135). The first phase of the research, where the data was subjected to statistical analysis, was followed by a comparative eye-tracking study, whose aim was to provide more detailed insight into the cognitive strategies employed when solving map-related tasks. More specifically, the eye-tracking study was expected to be able to detect possible differences between the cognitive patterns employed when solving extrinsic- as opposed to intrinsic visualization tasks. The results of an exploratory eye-tracking data analysis support the hypothesis of different strategies of visual information processing being used in reaction to different types of visualization.  相似文献   
980.
In the age when transport flows in the railway and road systems, information flows in the internet channels, etc. intensify, hazard distribution in the network systems becomes a more relevant and important issue. In the paper various theoretical hazard type distributions in the network systems are analysed. Conditions and assumptions that hazard in the network system cells would settle and became steady are defined. Cases are analysed, when hazard is initiated in one or several network nodes, while in other nodes hazard is decreased, i.e. they have immunity to the hazard. In all cases hazard distribution equilibrium equations are constructed and their solutions‘ existence conditions are defined. Theoretical results are illustrated by simulation of hazard fuel transportation in the Lithuanian roads. It is shown that using this methodology it is possible to construct an algorithm, which enables to operate and decrease fuel transportation hazard and risk. The novelty of the work is associated with employing Markov process to describe hazard distribution mechanism and to determine limited hazard distribution in the nodes of networks. The hazard of tank trucks in the network of Lithuanian roads has been assessed for the first time.  相似文献   
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