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221.
E. A. Kolotilov I. Mikolajewska P. M. Marrese U. Munari S. Yu. Shugarov B. F. Yudin 《Astronomy Letters》2001,27(1):51-57
We present our UBVRI photometry and spectroscopy of AS 338 performed in 1999–2000. Another eclipse of the hot component in this symbiotic binary system, the deepest one ever observed, occurred in September 1999. The U brightness declined by ~2m, the Hβflux decreased by a factor of ~2.3, and the [O III]γ5007 flux did not change. The hot component is eclipsed at orbital phases ?≈0.045–0.057. The U-B color index begins to appreciably fluctuate during an eclipse of the hot component and its circumstellar envelope. About 100 days after a strong outburst of 1995, the mean UBV brightness of AS 338 declined linearly in the ensuing five years at the same rate in all bands (ΔU/Δt≈10?3 mag/day). The brightness of the outer, uneclipsed parts of the circumstellar envelope also decreased, which is attributable to a reduction in the luminosity of the hot component against the rise in its temperature. The appearance of He II lines has not yet been recorded, though the optical brightness of AS 338 has already dropped by ~2m after the outburst. 相似文献
222.
223.
Walasek Richard A. 《GeoJournal》1981,3(1):37-47
Within the sizable literature on electricity demand relatively little attention is given to regional variations in electricity demand elasticities. This paper investigates 39 electric utility companies having a total of 93 separate operating regions in order to assess the nature of regional electricity demand elasticity variations. Residential, commercial, and industrial demand functions are estimated for each operating region using a flow adjustment model of demand. The resulting electricity price, measure of economic activity, and natural gas price elasticities vary regionally, but not in a systematic manner. The demand elasticities found in each sector range from highly inelastic to highly elastic with the pattern of elasticity variations exhibiting few spatial trends or relationships. Comparisons between operating region results and more aggregated statewide results indicate that statewide and national analysis of electricity demand masks much regional detail — a result which has important implications for energy policy making. 相似文献
224.
V.V. Bakhterev 《Russian Geology and Geophysics》2009,50(7):651-655
Physical, physicochemical, and mineralogical-petrographic methods have been applied to samples of ophiolite-hosted chromite ore from different deposits and occurrences in the Urals. Temperature dependences of dielectric loss obtained for nine chromite ore samples consisting of 95–98% Cr spinel show prominent peaks indicating a relaxation origin of the loss. The analyzed samples have the loss peaks at different temperatures depending mainly on H = (FeO/Fe2O3)? : (FeO/Fe2O3)??, where (FeO/Fe2O3)? and (FeO/Fe2O3)?? are, respectively, the ferrous/ferric oxide ratios in the samples before and after heating to 800 °C, and H is thus the heating-induced relative change in the FeO/Fe2O3 ratio. These peak temperatures vary from 550 °C (sample 1, high-Cr chromium spinel with more than 52% Cr2O3) to 750 °C (sample 2, aluminous and magnesian spinel with less than 30% Cr2O3), and H ranges correspondingly from 1.61 to 5.49. The temperature of the loss peaks is related with H as H = 34.30 ? 11.52N + 1.20N2, with an error of σ = 0.19 (N = T · 10?2, T is temperature in °C). 相似文献
225.
Dr. V. N. Konishchev 《GeoJournal》1987,15(2):135-139
Sediments of different lithological composition of a common feature — a relict system of thick syngenetic ice wedges — are called ice complexes. Three types of ice complex are distinguished in N Jakutia, with different topographic roles. They formed in the second part of the Upper Pleistocene. Author found that it is not the matter of transportation that accounts for the formation of the main features of their composition, but the specifics of lithogenesis first of all determined by the conditions of cryogenic weathering. 相似文献
226.
V. Yu. Zabrodin 《Russian Journal of Pacific Geology》2009,3(3):260-268
The late Jurassic reconstruction for the Ul’ban synclinorium was proposed based on the lithological and structural similarity of the Upper Permian and Mesozoic complexes of the Yankan-Dzhagdy and Ul’ban lithotectonic zones of the Amur-Okhotsk fold system. It was suggested that the Un’ya-Bom subzone of the Yankan-Dzhagdy LTZ is a fragment of the Ul’ban synclinorium (including its eastern centroclinal closure) that was detached and westward displaced (for 400–600 km) in the first half of the Cretaceous. 相似文献
227.
V.?V.?DyakonovEmail author O.?V.?Yapaskurt A.?E.?Kotelnikov K.?I.?Fedosova 《Moscow University Geology Bulletin》2017,72(5):320-325
The results of a microscope study of samples of felsic volcanic rocks from the upper horizons of the Sarbai Formation (O2–S1 sb) in the Southern Urals that compose the formation are presented. A detailed study of the samples and an evaluation of the results of a silicate analysis of these rocks showed their volcanogenic genesis. The rocks have been classified as volcanic glass that underwent several stages of transformation. Three newly-formed structural and textural types of mineralization were defined: spherulitic (felsophyric), axiolitic, and felsitic. 相似文献
228.
229.
230.
A method for comparative estimation of reliability in detection of gravity anomaly sources in indicated fragments of studied geological space is given. The possibility of creation of this estimation is connected with disparate ideas on different peculiarities of the structure of studied geological space and noise characteristics in observed fields. The model example and results of practical problem solution are viewed. 相似文献