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1.
多年冻土地区建筑物地基的热稳定性技术   总被引:1,自引:0,他引:1  
Thermal stabilization of soils (including freezing of thawed soils and cooling of permafrost) is known to be the effective method providing stable support for buildings and structures in cold regions.Seasonal thermo-stabilizers (STS) are mainly used in construction. The predicted climate warming because of natural and man-caused factors determines wide application of STS in permafrost regions. A STS transfers heat from its underground part (evaporator) to the aerial part (condenser) owing to natural temperature difference between them during a cold season. We have been working out and manufacturing different types of two-phase, vapor-liquid STS. Aluminum alloys are used in our STS to prevent corrosion and to increase their efficiency. They are successfully used in the northern regions of Western Siberia, in particular, at the railway Obskaya Bovanenkovo. The paper presents some technical parameters of new STS, the results of their experimental study and computer simulation, as well as experience features.  相似文献   
2.
The results of MHD numerical simulations of the formation and development of magnetized jets are presented. Similarity criteria for comparisons of the results of laboratory laser experiments and numerical simulations of astrophysical jets are discussed. The results of laboratory simulations of jets generated in experiments at the Neodim laser installation are presented.  相似文献   
3.
Kalinin  A. A.  Volkov  A. V.  Lobanov  K. V. 《Doklady Earth Sciences》2021,496(2):115-118
Doklady Earth Sciences - The Oleninskoe gold deposit is located in the northwestern part of the Kolmozero–Voron’ya greenstone belt (Kola Peninsula), in a sequence of amphibolite with...  相似文献   
4.
Changes in air temperature in administrative districts of the Russian Federation are studied. The in-regional homogeneity of modern climate changes is estimated based on several criteria for the first half of the 20th century and for the next period. The relation between regional changes in mean annual and seasonal temperatures and global air temperature is considered, and an empirical forecast for one or two decades is suggested to be made on its basis. Empirical regional forecasts of a rate of changes in mean annual air temperature are compared with the calculation results from five general circulation models.  相似文献   
5.
To evaluate the structure and photosynthetic activity of the phytoplankton of the northwestern part of the Sea of Japan, the results of the surveys conducted from February 26 to March 9, 2003, during the 30th cruise of the R/V Akademik Lavrentyev were used. The species composition was considered taking into account the influences of the hydrological conditions. In particular, the studied water area was divided into four zones with various sizes of the mixed layer depth (MLD). An inverse relationship between the MLD and the content of chlorophyll a (Chl a) in various zones was established. The diatom algae were the basic dominants of the composite structure of the phytoplankton everywhere. It is revealed that, at a MLD increase, smaller forms of microalgae receive development. The intrapopulation relations are caused by the adaptation of various species of phytoplankton to the influence of external factors, among which the size of MLD is fundamental.  相似文献   
6.
Representative sampling of a diamond-bearing basal horizon in the Carnian Stage (Upper Triassic) on the northeastern margin of the Siberian Platform revealed a wide spectrum of indicator minerals, first of all, garnets, whose compositions are the same as in the inclusions in the regional diamonds. Of special interest are garnets of potential eclogite paragenesis with an abnormally high impurity of MnO (0.5–3.2 wt.%), which was earlier detected in more than 20% of garnets present as inclusions in diamonds of northern Quaternary placers and recommended as a new mineralogical criterion for diamond presence. Subcalcic Cr-pyropes of dunite–harzburgite paragenesis were also found in variable amounts, from 0.7 to 3.9 rel.%, in the sample of 973 grains of pyropes of lherzolite and websterite parageneses. Three grains contain 11.9, 12.6, and 16 wt.% Cr2O3, which corresponds to the presence of 30–34% of Mg–Cr-knorringite component. Such pyropes have been revealed for the first time in the study region. Cr-spinels are a mixture of compositions typical of kimberlites and the regional alkali-ultrabasic rocks. All studied samples contain picroilmenites with a variable content of Cr2O3 impurity. Since Mg–Fe–Ca-garnets with Mg# < 35 can be partly hosted in metamorphic rocks of the Anabar Shield, the elevated content of Na2O impurity (> 0.09 wt.%) was also taken into account. The different contents of indicator minerals in the samples might be due to the variable composition of the diamond orebodies. The Carnian placers call for new systematic sampling. Special attention should be given to estimation of the composition of garnets of presumably eclogite paragenesis with elevated contents of TiO2, MnO, CaO, and Na2O and to search for perovskite and Nb-containing rutile. These minerals, together with zircons, are of interest for determining the U–Pb isotopic age of probable diamond orebodies—kimberlites.  相似文献   
7.
We present petrological, isotopic, and geochronological data on gabbro-picrite plutons from the Altai collisional system of Hercynides (eastern Kazakhstan). The geological, geochemical, and geochronological data suggest that these rocks are indicators of the activity of the Tarim plume. The gabbro and picrites formed in two stages (~293 and 280 Ma) in an acid-to-basic succession, explained by a model for the interaction of thermochemical plumes with the lithosphere. Early igneous activity, which gave rise to subalkalic gabbro plutons, reflects the first interaction between the ascending plume and the lithosphere, with low-melting sublithospheric protoliths. Further interaction was characterized by the sublithospheric spread of the plume head with intense heating of the lithospheric base and possible intrusion of deep melts, which resulted in the formation of Cu–Ni–PGE gabbro-picrite plutons in the Altai collisional system and Northwest China.  相似文献   
8.
Karnaukh  V. N.  Sergeev  A. F.  Lobanov  V. B.  Tishcenko  P. Ya. 《Oceanology》2019,59(6):995-998
Oceanology - During cruise 73 of the R/V Professor Gagarinskiy and cruise 53 of the R/V Akademik Oparin, oceanographic studies of the Sea of Japan and Sea of Okhotsk and the Northwest Pacific were...  相似文献   
9.
Compact relativistic jets in active galactic nuclei offer an effective tool for investigating the physics of nuclear regions in galaxies. The emission properties, dynamics, and evolution of jets in AGN are closely connected to the characteristics of the central supermassive black hole, accretion disk and broad-line region in active galaxies. Recent results from studies of the nuclear regions in several active galaxies with prominent outflows are reviewed in this contribution.  相似文献   
10.
According to the results of the international expedition aboard the R/Vs Roger Revelle and Professor Khromov in the summer 1999, areas with low oxygen contents (below 210 μM/kg) and those with increased contents of dissolved inorganic carbon and phosphates were found that roughly coincided with one another. These areas are located near the bottom on the southwestern slope of the Tsushima Basin in the region of the Korea Strait and on the continental slope in the region of the Tatar Strait in the northern part of the sea at about 46° N. The set of hydrochemical data points to a high geochemical activity in the near-bottom layer of the areas noted. This activity is confirmed by direct observations of the composition of the interstitial water in the sediments collected in the northern part of the sea during the expedition of R/V Akademik M.A. Lavrent’ev in 2003. It was supposed that the main cause of the increased geochemical activity is the runoff of suspended and dissolved matter from the Korea and Tatar straits. In the areas mentioned, the near-bottom waters are characterized by low values of the nitrogen-phosphorus ratio (below 10), which is geochemical proof of the denitrification process occurring under the conditions of high oxygen concentrations characteristic of the Sea of Japan. Based on the value of the annual production in the Sea of Japan, a rate of denitrification equal to 3.4 × 1012 gN/year was calculated. Hence, it is confirmed that the geochemical processes in the near-bottom layer have a direct influence on the spatiotemporal characteristics of the hydrochemical properties of the waters of the Sea of Japan.  相似文献   
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