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51.
Andrey G. Tlatov Valeria V. Vasil’eva Valentina V. Makarova Pavel A. Otkidychev 《Solar physics》2014,289(4):1403-1412
We used an automatic image-processing method to detect solar-activity features observed in white light at the Kislovodsk Solar Station. This technique was applied to automatically or semi-automatically detect sunspots and active regions. The results of this automated recognition were verified with statistical data available from other observatories and revealed a high detection accuracy. We also provide parameters of sunspot areas, of the umbra, and of faculae as observed in Solar Cycle 23 as well as the magnetic flux of these active elements, calculated at the Kislovodsk Solar Station, together with white-light images and magnetograms from the Michaelson Doppler Imager onboard the Solar and Heliospheric Observatory (SOHO/MDI). The ratio of umbral and total sunspot areas during Solar Cycle 23 is ≈?0.19. The area of sunspots of the leading polarity was approximately 2.5 times the area of sunspots of the trailing polarity. 相似文献
52.
The monthly number of polar faculae of the Sun were determined from white-light images at spectral band (eff) = (4100 ± 200) Å obtained at the Kislovodsk Solar Station during 1960–1994. Corrected monthly numbers were obtained with the help of the visibility function. The level of polar activity larger than 1 above the monthly running mean was calculated, and the relation between the polar faculae and sunspot cycle was studied. We confirmed earlier results (Makarov and Makarova, 1987) that the monthly number of polar faculae, NPF
m
(t) correlates with the monthly sunspot area A
m
(Sp)(t + T) with a time shift T 6 yr. The new polar faculae cycle began in the middle of 1991. Peculiarities of the first part of sunspot cycle 23 are discussed.Guest scientist with the University of Arizona and Zetetic Institute. Tucson, Arizona 85719, U.S.A. 相似文献
53.
We present CCD VIC photometry in a field 1.9 − 1.3 square arcmin and positioned about 3 arcmin north-east of the centre of M82. More than 100 stars have been identified and measured above the photometric limits V = 23m.5, I = 22m. Most of the objects fainter than V ≈︁ 20m should be members of M82 as expected from the statistics of foreground stars. Starlike as well as 2–3 somewhat diffuse objects - candidates of globular clusters - preferentially occupy yellow colours in the colour-magnitude diagram; extreme blue and red objects are missing. The colour-magnitude diagram indicates continuing star formation in this part of the disk. The absence of blue stars is caused by reddening; no convincing explanation is found for the missing red supergiants. Young stars are distributed throughout the whole field, the youngest being concentrated in associations at the SW edge of the field. To cope with the very irregular background created by the galaxy' s main body and with the low contrast of many of the stars against this background, a modified photometric method is introduced in which the background is estimated using the intensities in a ring drawn very tightly around the star in the wings of the point spread function. 相似文献
54.
Using the line profiles of [Fe x] 6374 å and [Fe XIV] 5303 å emission lines observed during five total solar eclipses, we address the problem whether the solar corona is static or contains moving features. Many of the profiles of both emission lines have complicated shapes, which we interpret as an evidence for the existence of many, small, moving features in the corona. The line-of-sight velocities observed by other investigators (e.g. Desai, Chandrasekhar & Angreji 1982) also support this view. On the other hand, about 15 recent interferometric and multislit investigations of coronal emission lines have not shown evidence of moving elements. We suggest that this is due to insufficient spatial resolution. 相似文献
55.
The paper reports the results of the analysis of the data on polar faculae for three solar cycles (1960–1986) at the Kislovodsk Station of the Pulkovo Observatory and on polar bright points in Ca ii K line for two solar cycles (1940–1957) at the Kodaikanal Station of the Indian Institute of Astrophysics. We have noticed that the monthly numbers of polar faculae and polar bright points in Ca ii K line and monthly sunspot areas in each hemisphere of the following solar cycle have a correlation with each other. A new cycle of polar faculae and polar bright points in the Ca ii K line begins after the polar magnetic field reversal. We find that the smaller the period between the ending of the polar field reversal and the beginning of a new sunspot cycle is, the more intense is the cycle itself. The intensity of the forthcoming solar cycle (cycle 22) and the periods of strong fluctuations in activity expected in this cycle are also discussed. 相似文献
56.
Boeva N. M. Makarova M. A. Shipilova E. S. Slukin A. D. Melnikov F. P. Karimova O. V. Bortnikov N. S. 《Doklady Earth Sciences》2022,507(1):871-880
Doklady Earth Sciences - The Central bauxite deposit on the territory of the Russian Federation is a unique geological object. It hosts both primary lateritic bauxites and products of their... 相似文献
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59.
L. V. Zakharikhina Yu. S. Litvinenko N. I. Ryakhovskaya V. V. Gainatulina N. Yu. Arguneeva M. A. Makarova 《Journal of Volcanology and Seismology》2016,10(3):203-217
It is found that the overwhelming majority of mobile forms of the chemical elements (up to 99%) that are thought to produce favorable effects when they arrive with volcanic ash to soils and supply additional elements that enhance the bioproductivity of ecosystems do not come in the form of ash particles, but in a gas-dissolved form directly from volcanic aerosol. Volcanic ash when considered independently of volcanic eruptions does not contain considerable amounts of accessible forms of chemical elements that would enable us to consider them as sources of nutrient elements for living organisms. However, the extensive range of elements that are contained in ash in ratios that are necessary for effective life activities invests these elements with catalytic properties that regulate the nutrient regime of plants and that can be used in agriculture in combination with lower amounts of traditional fertilizers to produce substantial (up to 72%) yield increases and to improve the quality of agricultural products. 相似文献
60.
B. M. Koprov V. M. Koprov T. I. Makarova G. S. Golitsyn 《Boundary-Layer Meteorology》2004,111(1):19-32
Simultaneous measurements of the instantaneous values of absolute temperatureat seven heights within the lower 36 m of the atmospheric boundary layer underdifferent stability conditions were carried out, accompanied by measurements ofthe wind velocity components at two levels and of solar radiation flux at the surface.The data obtained allow one to investigate individual convective cells known ascoherent structures (CS). Outside the CS, i.e., during quiet periods, an instanttemperature profile is in close agreement with the dry-adiabatic lapse rate, butwithin CS the temperature changes much faster with height, and the shape ofthe profile varies significantly.A method was developed to transform temperature records from sensors atseveral heights into an other form, namely, into temporal variations of theheights of isothermal surfaces. Since coherent structures were found to advectwith the mean wind velocity, these temporal height variations may be transformedinto the spatial ones, i.e., into the xoz-plane section of the temperature field.In such a pictorial presentation coherent structures look like asymmetric columnsof heat, penetrating the whole atmospheric surface layer.Coherent structures also exist in the stable stratified surface layer, but they have aninverse asymmetry and occupy only the lower several metres. Wavelike activitydominates in the upper part of the stable surface layer.The characteristic time of surface-layer adjustment to the rapid changes of solarradiation (due to cloud shadows or cloud gaps) was found to be on the order ofone minute. Such a time interval is required for coherent structure to reach the topof surface layer. 相似文献