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991.
Ohne Zusammenfassung 相似文献
992.
Prof. T. Boldizsár 《Pure and Applied Geophysics》1956,34(1):66-70
Summary The geothermal gradient in the Carpathian Basin lies between 40–70 C/km. According to careful measurements in shafts the value of terrestrial heat flow in the southern part of Hungary is (2.055–3.066)·10–6 cal/cm2 sec. These measurements are believed the first ever attempted in continental Europe. Systematic heat flow measurement are being extended to other part of this country. 相似文献
993.
994.
Dr. F. Verzár 《Pure and Applied Geophysics》1959,42(1):21-23
I has been shown that irradiation of air by sun-rays leads to a formation of atmospheric condensation nuclei, as measured with the automatic nucleus counter (1).To control the influence of the material, experiments were done in a gasometer where a rubber balloon was built in, also in a metal container covered either with uviol glass or window glass, or with air in a polyethylene balloon. The same influence of sunrays was observed in each case.Similar experiments were then done with compressed air from a metal container, or with oxygen gas, nitrogen gas or nitrous oxide all from metal containers. In all cases sun-rays produced condensation nuclei; the effect was present both at 1800 m and at 270 m altitude. Diffuse sunlight with high clouds also had an effect. Infra-red radiation and mechanical shaking were without result, but ultraviolet rays from a quartz-mercury lamp increased the nucleus count of the balloon whether it contained air or one of the above-mentioned gases.As yet it has not been possible to decide the mechanism of formation of these nuclei and what their meteorological and biological role might be.The detailed paper will appear later in «Geofisica pura e applicata». 相似文献
995.
Groundwater-quality monitoring plays an important role in groundwater protection and quality conservation. National, regional, and site-specific monitoring programs operating in Czechoslovakia concern collection of back-ground data on groundwater quality and regional diffusion pollution problems. Site-specific monitoring is concerned with point sources of pollution. Pilot monitoring stations with automatic data acquisition systems optimize monitoring methods, design of monitoring networks, sampling techniques, and frequency and selection of the variables analyzed. Ground-water-quality monitoring in Czechoslovakia supports decision and policy making in areas of intensive farming. Time and spatial changes in shallow vulnerable aquifers are evaluated in several areas of national territory and support integrated land-use planning and groundwater protection management. 相似文献
996.
E. D. Poezd Vladimír Fiala Pavel Tříska Reviewer S. Fischer 《Studia Geophysica et Geodaetica》1987,31(1):73-84
Summary The existence of a coupling, due to wave-particle resonance interaction, between magnetospheric radio emissions, i.e. auroral kilometric radiation (AKR), and auroral radio noise(AN), separated in an inhomogeneous magnetospheric plasma by an opacity barrier, is studied. It is proved that the ballistic process can only take place on the electrons of the superthermal component of the plasma, i.e. on particles of auroral electron fluxes of the inverted V type, due to finite width of the AKR spectral lines, which amounts to 1 kHz. Analyses indicate that its effectiveness is sufficient to explain radio emission coupling and that it increases with the degree of auroral activity.
¶rt;m n mu mau ¶rt; aumu a¶rt;uuuu — um uu u() u aau a¶rt;uau, a¶rt;u ¶rt;¶rt; aum na am namu, aumu u, ma mm mam a au¶rt;mu a-amua. aa, m u-a uu nma uu , ma mam 1 , aumuu n m mm m a ma a¶rt;mn nm na — a amua aa m nm muna nm V. u m mum, a naam u, aam ¶rt;mam ¶rt; u u a¶rt;uuu, nu a amam uu mnu aa amumu.相似文献
997.
Studia Geophysica et Geodaetica - В зависимости от... 相似文献
998.
Résumé Les scories basanitiques du volcan de l'Oued Temorte (Massif de l'Atakor, Sahara algérien) contiennent de nombreux minéraux caractéristiques des stades de cristallisation intratellurique dans les magmas basiques alcalins: kaersutite, salite ferrisodique, zircon, titanomagnétite et ferripléonaste. L'étude a porté essentiellement sur les spinelles et sur les transformations qu'ils subissent par oxydation dans les derniers stades précédant l'éruption. L'étude au microscope métallographique des diverses phases observées (titanomagnétite, ferripléonaste, spinelle, ilménite, titanohématite, pseudobrookite, corindon) complétée par 16 analyses chimiques effectuées pour la plupart à l'aide de la microsonde électronique, permet de préciser le mécanisme de l'oxydation et d'évaluer, à l'aide des données expérimentales, les fugacités d'oxygène (fO2) contrôlant la cristallisation de ces phases. Les valeurs de fO2 ainsi obtenues (10–8,5 à 10–2,5 atm à 1200°) sont nettement supérieures à celles déterminées antérieurement à partir des basaltes. D'une façon générale, il semble que les fO2 qui s'exercent au cours de la cristallisation des magmas basiques alcalins soient plus fortes que dans les autres types de laves basiques. L'accent est enfin porté sur la nécessité, pour évaluer les conditions de cristallisation et en particulier l'évolution de fO2 au cours de la différenciation, de distinguer les minéraux appartenant aux stades de cristallisation intratellurique des minéraux cristallisant après l'éruption.
Contribution to the study of early parageneses of alkaline basalts: The spinels of the oued Temorte volcano (Atakor Massif, Algerian Sahara)
Scoriaceous basanites from an algerian stratovolcano (Oued Temorte, Atakor, Sahara) contain many minerals thought to be typical of intratelluric stages of crystallization in alkali basic magmas: kaersutite, ferrisodic salite, zircon, titanomagnetite, ferripleonaste. This paper is mainly concerned with spinels and the oxidation processes that take place before eruption of the lava. A series of oxidation reactions were established, and an estimation of the oxygen fugacities (fO2) controlling the cristallisation could be made, using metallographic microscope studies of the resulting phases (titanomagnetite, ferripleonaste, spinel, ilmenite, titanhematite, pseudobrookite, corundum) and 16 chemical analysis (13 being electron microprobe determinations). The fO2 values obtained (10–8,5 to 10–2,5 atm at 1200° C) are higher than those proposed by various authors for basaltic lavas.In the conclusion, the authors insist that a clear distinction should be made between preeruption phases and minerals that cristallise after eruption, in order to determine the physical conditions of crystallization, in particular estimate the variations of fO2 in order to evaluate the importance of these various factors in the processes of magmatic differenciation.相似文献
999.
Lubomír Kubáček Lea Bartalošová Ján Pecár Reviewer F. Charamza 《Studia Geophysica et Geodaetica》1978,22(1):1-12
Summary Given a configuration of points of a levelling traverse, it is possible to determine their heights according to various plans by applying various optimization criteria. D-, restricted D-and L-optimum plans for various configurations are generally treated. Of two plans belonging to one and the same configuration we consider the one whose determinant, or trace of the covariance matrix of adjusted heights is minimum, to be optimal.Dedicated to RNDr Jan Pícha, CSc., on his 60th Birthday 相似文献
1000.
Marcela Laštovičková Vladimír Kropáček Reviewer F. Janák 《Studia Geophysica et Geodaetica》1976,20(3):265-272
Summary In investigating the electric conductivity of rocks as a function of the temperature it was found that rocks containing ferrimagnetic minerals display a change in the slope of the functionlg =f(1/T) in the neighbourhood of the Curie temperature . In order to explain these changes the curveslg =f(1/T) and the Curie temperatures , obtained from the temperature dependence of the saturated magnetization Js=f(T), were compared. Eight samples of basalts, 2 samples of haematite and magnetite were used to demonstrate the relation between and the changes in the pattern of the electric conductivity, caused by the variations of the exchangeable energy of ferrimagnetic minerals. 相似文献