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301.
Transfer of resonance radiation in an infinite medium is considered as a process of random walks of photons. Close relation is shown to exist between the problems of transfer of line radiation and the stable distributions of the probability theory. This relation is used as a basis of a new method for the investigation of the asymptotic properties of the radiation field far from the sources. 相似文献
302.
E. Sh. Elizbarashvili M. E. Elizbarashvili Sh. E. Elizbarashvili M. G. Pipiya L. G. Kartvelishvili 《Russian Meteorology and Hydrology》2020,45(1):58-62
The number of days with blizzard, the intensity, duration, periods of occurrence, and dynamics of blizzards in the mountain regions of Georgia are investigated using observational data from 20 weather stations. The features of wind and temperature regimes of blizzards are revealed. 相似文献
303.
304.
A.P. Berzina A.N. Berzina V.O. Gimon R.Sh. Krymskii A.N. Larionov I.V. Nikolaeva P.A. Serov 《Russian Geology and Geophysics》2013,54(6):587-605
Two intrusive complexes are recognized at the Shakhtama deposit: Shakhtama and ore-bearing porphyry. The U–Pb zircon dates (SHRIMP II) are 161.7 ± 1.4 and 161.0 ± 1.7 Ma for the monzonites and granites of the Shakhtama complex and 159.3 ± 0.9 and 155.0 ± 1.7 Ma for the monzonite- and granite-porphyry of the ore-bearing complex. The igneous complexes formed in a complex geodynamic setting in the late Middle Jurassic and early Late Jurassic, respectively. The setting combined the collision of continents during the closure of the Mongol-Okhotsk ocean and the influence of mantle plume on the lithosphere of the Central Asian orogenic belt. The intrusion of the Shakhtama granitoids took place at the end of the collision, and the intrusion of porphyry of the ore-bearing complex, during the change of the geodynamic setting by a postcollisional (rifting) one. The complexes are composed of monzonite–granite series with similar geochemical characteristics of rocks. The performed geological, geochemical, and isotope-geochemical studies suggest that the sources of magmas were juvenile crust and Precambrian metaintrusive bodies. The juvenile mafic crust is considered to be the predominant source of fluid components and metals of the Shakhtama ore-magmatic system. The granitoids of both complexes include calc-alkalic high-K rocks with typical geochemical characteristics and with characteristics of K-adakites. These geochemical features indicate that the parental melts of the former rocks were generated at depths shallower than 55 km, and the melts of the latter, at depths of 55–66 km. K-adakite melts resulted from the melting of crust submerged into the mantle during the lithosphere delamination, which was caused by the crust thickening as a result of the repeated inflow of basic magma into the basement of the crust and tectonic deformations in its upper horizons. The high-Mg monzonitic magma produced under these conditions ascended and was mixed with melts generated in the upper horizons, which accounts for the high Mg contents of the Shakhtama granitoids. The similar compositions and petrogeochemical characteristics of the granitoids of the Shakhtama and porphyry complexes point to the same sources, transport paths, and evolution trend of their parental melts. This indicates that the igneous rocks of both complexes are products of the same long-living magmatic system, which produced Mo mineralization at the final stage. The favorable conditions for the ore production in the magmatic system during the formation of the porphyry complex appeared as early as the preceding stage—during the formation of the Shakhtama complex, which we regard as a preparatory stage in the evolution of the ore-magmatic system. 相似文献
305.
Yu.I. Velikodsky N.V. Opanasenko V.V. Korokhin V.G. Kaydash Sh.A. Ehgamberdiev 《Icarus》2011,214(1):30-45
A 2-month series of quasi-simultaneous imaging photometric observations of the Moon and the Sun has been performed at Maidanak Observatory (Uzbekistan). New absolute values of lunar albedo have been obtained. Maps of lunar apparent albedo and equigonal albedo at phase angles 1.7-73° at wavelength 603 nm are presented. The standard deviation of our data from a best-fitted phase curve is 2%. The average ratio of the Clementine albedo to ours is 1.41. While the ratio of ROLO albedo to ours is 0.87, our data are in agreement with independent measurements of absolute albedo by Saiki et al. (Saiki, K., Saito, K., Okuno, H., Suzuki, A., Yamanoi, Y., Hirata N., Nakamura, R. [2008]. Earth Planets Space 60, 417-424) at a phase angle near 7°. A phase ratio imaging near opposition (1.6°/2.7°) shows almost the same ratio for maria and highlands, though bright craters (e.g., Tycho, Copernicus, Aristarchus) clearly reveal smaller slopes of phase function. This is an unexpected result, as the craters are bright and one could anticipate a manifestation of the coherent backscattering effect resulting in the opposition spike increasing at so small phase angles. 相似文献
306.
为获得琼胶酶活性高产菌株,对采集的海水样品进行了产酶微生物的分离、筛选和鉴定。经过平板培养预筛和两次摇瓶培养筛选,从浙江省舟山市普陀区近海海水样品中分离到一株琼胶酶产生菌G-5,该菌株液体培养产酶活力可达到413.8 U/mL。G-5菌株的菌落呈乳白色、半透明、表面湿润;菌体革兰氏染色阴性,大小0.58~0.69 μm1.50~2.26 μm;光学显微镜下呈短杆状,略有弧形。G-5菌株的16S rDNA序列与NCBI数据库中15个弧菌属(Vibrio)菌株的16S rDNA有98%的同源性,可以确定G-5菌株是一株弧菌(Vibrio sp.)。 相似文献
307.
V. N. Koneshov I. V. Koneshov V. V. Klevtsov A. V. Makushin Yu. L. Smoller S. Sh. Yurist Yu. V. Bolotin A. A. Golovan 《Izvestiya Physics of the Solid Earth》2013,49(1):77-79
This work describes the different sets of instruments and methodic approaches for testing the models of gravity anomalies by repeated airborne gravimetric surveys in the polar cap regions of the Earth. The survey design including the specifications for flying the survey profiles and the arrangement of the base stations in polar areas is described, and the necessary modifications of the airborne gravity metering complexes for high-latitude measurements are suggested. 相似文献
308.
V.G. Shevchenko I.N. Belskaya I.G. Slyusarev Yu.N. Krugly V.G. Chiorny N.M. Gaftonyuk Z. Donchev V. Ivanova M.A. Ibrahimov Sh.A. Ehgamberdiev I.E. Molotov 《Icarus》2012,217(1):202-208
CCD-photometry of three Jupiter Trojan asteroids were carried out to study their opposition effect. We obtained well-sampled magnitude–phase curves for (588) Achilles, (884) Priamus, and (1143) Odysseus in the maximal attainable phase angle range down to 0.1–0.2°. The magnitude–phase relations have a linear behavior in all observed range of phase angles and do not show any non-linear opposition brightening. We have not found any confident differences between phase slopes measured in B, V and R bands. The values of the measured phase slopes of Trojans are different from available data for Centaurs. They are within the range of phase slopes measured for some low-albedo main belt asteroids, also exhibit a linear behavior down to small phase angles. An absence of non-linear opposition brightening puts constraints on the surface properties of the studied objects, assuming very dark surfaces where single scattering plays dominating role.We also determined the rotation periods, amplitudes, the values of color indexes B–V and V–R, and the absolute magnitudes of these asteroids. 相似文献
309.
The phosphorus (P) resources worldwide are limited, and the prices of commercial P fertilizer continue to increase. Therefore, the use of P containing wastes is important for P recycling in agriculture. The P fractionation methods have been widely applied to characterize the effect of land use practice on soil P dynamics. Information about effect of organic manures on available P and inorganic P (Pi) fractions in calcareous soils of Chaharmahal va Bakhtiari province is limited. The objectives of this research were to study the effect of municipal compost (MC) on available P and Pi forms in five calcareous soils. Municipal compost was applied at the rates of 0, 0.5, 1.0, 1.5 and 2.0% (w/w). Samples were incubated at 25?±?1°C and 20% moisture content for 150?days. At the end of incubation, available P in MC-treated soils was extracted by Olsen, AB-DTPA and 0.01?M CaCl2 methods. Also, phosphorus was fractionated chemically into labile P (LP), non-occluded P(NP), re-adsorbed P (RP), occluded P (OP), calcium phosphates (CaP) and residual P. The results showed that there was a linear increase in soil available P with MC application. There was a significant positive relationship between Olsen-P, AB-DTPA-P and 0.01?M CaCl2-P, and MC additions with slopes ranged from 0.471 to 0.583, 0.032 to 0.106, and 0.033 to 0.081, respectively. The increase in soil test P (STP) from MC additions was not related to the initial STP of the soils. A sharp increase in LP, NP and CaP and decrease in residual P concentration occurred in all soils with MC application. It can be concluded that MC applied to calcareous soils may enhance P nutrition of plants. Furthermore, applied P partitioning into the relatively available forms means the potential erosion losses of P to streams and other bodies of water. 相似文献
310.
Geomagnetism and Aeronomy - The latitudinal-temporal changes in wavelet spectra for the number of coronal bright points (CBPs) in solar-activity (SA) cycles 23 and 24 are analyzed with the Morlet... 相似文献