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11.
Carbonaceous matter (CM) in shales of some deposits and occurrences of the Russian Far East has been studied by scanning and transmission electron microscopy, Raman spectroscopy, and X-ray phase and differential thermal analyses. It was shown that the carbonaceous matter in the high-temperature shales (amphibolite facies) of the Soyuznoe deposit is represented by holocrystalline graphite, while the low-temperature (greenschist facies) shales of the Sutyr and Kimkan sequences contain mainly nanocrystalline graphite. It was substantiated for natural objects that platinum is assimilated by graphite at high temperatures. This should be taken into account in planning the prospecting works, as well as in developing a technique for enrichment of carbonaceous ore, because high-temperature carbonaceous shales with holocrystalline graphite are promising for Pt, unlike their low-temperature analogues with nanocrystalline graphite.  相似文献   
12.
Characteristics of surface and subsurface waters in Altai krai are discussed and the potentialities of the use of groundwater from different aquifers for domestic needs are evaluated. The degree of pollution of water bodies by heavy metal compounds and oil products is analyzed.  相似文献   
13.
This paper describes the aims, objectives and first results of the observational program for the study of distant core-collapse supernovae (SNe) with redshifts z ≲ 0.3. This work is done within the framework of an international cooperation program on the SNe monitoring at the 6-m BTA telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences, and other telescopes. We study both the early phases of events (SN type determination, redshift estimation, and a search for manifestations of a wind envelope), and the nebular phase (the effects of explosion asymmetry). The SNe, associated with cosmic gamma-ray bursts are of particular interest. An interpretation of our observational data along with the data obtained on other telescopes is used to test the existing theoretical models of both the SN explosion, and the surrounding circumstellar medium. In 2009 we observed 30 objects; the spectra were obtained for 12 of them. We determined the types, phases after maximum, and redshifts for five SNe (SN 2009db, SN 2009dy, SN 2009dw, SN 2009ew, SN 2009ji). Based on the obtained photometric data a discovery of two more SNe was confirmed (SN 2009bx and SN 2009cb). A study of two type II supernovae in the nebular phase (SN 2008gz and SN 2008in) is finalized, four more objects (SN 2008iy, SN 2009ay, SN 2009bw, SN 2009de) are currently monitored.  相似文献   
14.
We first used semipermeable membrane devices as samplers to evaluate concentrations of organochlorines and PAHs in the Brisbane River in 1998. Here we revisit this work and repeat the study a decade later in the same season (summer), also taking account of results from a similar study involving PAHs in the summer of 2001-2002. The accumulation of organochlorines and most PAHs in the samplers in the recent assessment was substantially less than in the 1998 deployment, suggesting that the ambient concentrations of these chemicals have decreased considerably over the last decade. In all cases there was high reproducibility of the mass of chemicals accumulated in the sampler. We used performance reference compounds in the later deployment, and assuming that the kinetics were similar in both deployment periods, we estimate that the concentration of dieldrin, the organochlorine found at highest concentrations, decreased from approximately 3.9 ng/L to about 1.4 ng/L. The decrease of most other analytes of interest including DDE and DDD was greater, potentially indicating that dieldrin is still entering the Brisbane River through run-off from urban areas where it was used widely for treatment of termites until 1995. DDT use in Australia ceased in the mid 1980s.  相似文献   
15.
Some karst regions of Indonesia (Java, Sulawesi, Bali, Madura), on closer examination geomorphologically and hydro-geologically quite distinct from each other, are checked with regard to land-use, settlement and other economic and cultural significance. Brief comparisons are made to similar regions from the Philippines (Bohol), Thailand etc. An amazingly strong differentiation, especially of the rice-cultivation systems, is determined by the varying access to water. Some densely populated limestone regions are suffering even from critical water supply for human consumption, cattle etc. Proposals for improvement and rural development are given. The comparison of agricultural landscape types under changing geo-ecological conditions yield fine examples of closely interwoven man-earth eco-systems.  相似文献   
16.
We present a hardware/software complex for photometric observations with high time resolution. The hardware consists of a detector, a recording system which is a "time - coded" converter, a PC/AT 486 computer and a tape recorder. As a detector we can use any device that provides its output in such a way that for every detected quantum there is a correspondent standard impulse with additional information on the quantum - space coordinates, frequency, polarization, etc. A special "time - coded" converter "Quantochron" registers the quanta arrival times with an accuracy of ± 20 nanoseconds stores in the computer the 16-bit codes as well as the 16-bit codes of additional information. At present, the photometer complex allows to register without distortion the flux events up to 380 kHz. We describe the special methods and software capable of searching and analyzing any type of photon flux intensity variations. The results of the high time resolution investigations of a number of relativistic and fast variable objects, such as black hole candidates, LMXB, pulsars and flare stars, are presented.  相似文献   
17.
18.
Izvestiya, Atmospheric and Oceanic Physics - This article analyzes seasonal and interannual dependences of brightness temperature in different zones of the Gulf of Ob according to data from the...  相似文献   
19.
The “Big Trio” program is conducted at the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS) aiming to investigate a sample of sources with steep and ultra-steep spectra fromthe RCcatalog obtained on the basis of observational data of the “Cold” survey. The population of distant FRII type radio galaxies with steep spectra is of particular interest, since new data indicate the presence of black holes with masses of more than 109 M which already formed in these giant stellar systems in the first billion years of life of the Universe, as well as their connection with emerging clusters. There are three sources with z sp > 3 in the sample. According to the observations of the 6-m SAO RAS telescope, the archival data of Subaru and Spitzer, an increased density of objects and several Lyα-emitters have been detected near one of the most powerful radio galaxies, RCJ0311+0507 (4C+04.11) with z = 4.51, which is the second most distant of the known FRII-type galaxies. Another object— RCJ1740+0502 with z = 3.57, is a possible dual AGN candidate. The third source, RCJ0105+0501, is an FRII-type galaxy (z = 3.138) with a host galaxy of a complex structure, possibly generated by interaction in a close pair of galaxies. These radio sources have high radio luminosity (L 500MHz ≈ 1028–1029WHz?1), which requires the presence of a giant black hole with a sufficient accretion rate, and also with a rapid rotation, which in turn can be provided by major merging.  相似文献   
20.
We investigated the kinematics of the pulsar wind nebula (PWN) in the old supernova remnant CTB 80 using the Fabry-Perot interferometer of the 6-m Special Astrophysical Observatory telescope. In addition to the previously known expansion of the system of bright filaments with a velocity of 100–200 km s?1, we detected weak high-velocity features in the Hα line at least up to velocities of 400–450 km s?1. We analyzed the morphology of the PWN in the Hα, [S II], and [O III] lines using HST archival data and discuss its nature. The shape of the central filamentary shell, which is determined by the emission in the [O III] line and in the radio continuum, is shown to be consistent with the bow-shock model for a significant (about 60°) inclination of the pulsar’s velocity vector to the plane of the sky. In this case, the space velocity of the pulsar is twice as high as its tangential velocity, i.e., it reaches ?500 km s?1, and PSR B1951+32 is the first pulsar whose radial velocity about 40 km s?1 has been estimated from PWN observations. The shell-like Hα-structures outside the bow shock front in the east and the west could be associated with both the pulsar’s jets and the pulsar wind breakthrough due to the layered structure of the extended CTB 80 shell.  相似文献   
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