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161.
Two cirrus cloud systems observed during the winter of 2001 at the Southern Great Plains site of the Atmospheric Radiation Measurements program in Oklahoma, USA are studied because of the distinct neutrally stratified layers formed within the clouds. Observations are obtained with 35 GHz millimeter-wave radar and backscattering cross-section η(t) signals within radar-reflectivity restricted sublayers of the clouds are analyzed. The neutrally stratified layers of cirrus clouds are known to be associated with the existence of generating cells. The statistics of radiative properties within the neutrally stratified layers is obtained to be non-Gaussian and time-dependent. The purpose of this research is to derive a model of the cloud-generating cells layer in cirrus based on the statistics of observations. The Fokker–Planck equation approach provides suitable framework to treat non-Gaussian, time-dependent probability density functions (pdfs) such as those found for the η(t) signals. It is shown that the deviations from Gaussianity of radiative properties of the neutrally stratified generating cells layer in cirrus can be modeled by linear stochastically perturbed dynamics with multiplicative noise statistics. Because the multiplicative noise is often identified with state-dependent variations of stochastic feedbacks from unresolved system components it is expected that derived stochastic model will be useful for parameterization of cirrus in global circulation models (GCMs). 相似文献
162.
V. M. Chechetkin S. S. Gershtein V. S. Imshennik L. N. Ivanova M. Yu. Khlopov 《Astrophysics and Space Science》1980,67(1):61-97
The present work studies the hydrodynamic process of thermonuclear explosion of hydrostatic equilibrium, degenerate carbon-oxygen
cores withM
C=1.40M
⊙ with different values of central densityϱ
c
within the interval 2 × 109 <ϱ
c
< 3 × 1010 g cm−3. The initial temperature distribution has been determined by the preceding thermal stage of explosion. The calculations successively
include the kinetics of thermonuclear burning, the kinetics of β-processes, and neutrino energy losses. By considering the
neutrino mechanism of heating and carbon ignition we obtained in our numerical hydrodynamic calculations two characteristic
versions of the development of an explosion: (a) at 2 × 109 <ϱ
c
< 9 × 109 g cm−3 there is disruption of the whole star with either complete or partial burning of the carbon and a 1050–1051 erg kinetic energy; and (b) at 9 × 109 <ϱ
c
< 3 × 1010 g cm−3 the stellar core collapses into a neutron star with partial outburst of the outer envelope with a smaller kinetic energy
of 1049–1050 erg. The paper proposes and details a hypothesis (the scenario of supernovae and the formation of neutron stars) on the first
version of explosion, corresponding to SNII, and on the second, supplemented by some mechanism of slow energy release into
the envelope expelled from the newly formed neutron star, corresponding to SNI. On the basis of the proposed hypothesis a
satisfactory agreement with the observed masses and energies of the supernovae envelope, their light curves and spectra, as
well as with the data on their chemical composition has been obtained. For this agreement we must assume that type I pre-supernovae
are almost bare compact carbon-oxygen stellar cores, and that type II presupernovae are red supergiants. It is most probable
that the evolution of type I pre-supernovae occurs in close binaries while the evolution of type II pre-supernovae seems to
be very similar to the evolution of a single star. 相似文献
163.
164.
S. V. Vysotskiy S. A. Shcheka A. V. Barkar V. L. Ivanova A. A. Karabtsov 《Russian Journal of Pacific Geology》2007,1(1):98-105
Detailed study of garnet and garnet-pyroxene inclusions from alkali basalts of Primorye allowed us to distinguish two heterogeneous mineral assemblages: early (primary) and late (secondary) ones. The former reflects the initial stage of rock formation and consists of garnet, clinopyroxene, orthopyroxene, plagioclase, and ilmenite. The latter, orthopyroxene-plagioclase-spinel assemblage replaces garnet. The transformation of garnet typically accompanies the change in the garnet assemblage to a higher temperature pyroxene-plagioclase-spinel assemblage owing to its entrainment in high temperature magma. The study of the chemical composition and textural relationships of minerals, together with the examination of similar mineral assemblages from alkali basalts around the world and mafic-ultramafic intrusions, led us to the conclusion that the garnet inclusions of Primorye are typical xenoliths and xenocrysts representing fragments of tholeiite intrusions of an ophiolite complex that were transformed in the host basaltic magma. 相似文献
165.
166.
A. M. Zvyagintsev V. A. Zhuravleva N. S. Ivanova G. M. Kruchenitskii I. Yu. Shalygina 《Russian Meteorology and Hydrology》2007,32(8):547-550
The review is compiled based on the results of the operation of the Total Ozone (TO) Monitoring System in the CIS and Baltic countries, functioning in the operational regime at the Central Aerological Observatory (CAO). The monitoring system uses the data from the national network of M-124 filter ozonometers, operated under the methodological control of the Main Geophysical Observatory (MGO). The quality control of the entire system is performed in real time based on the observations with the satellite OMI equipment. The basic results of TO observations for each month of the second quarter of 2007 and for a quarter as a whole are summarized. Results of regular surface ozone observations that have been carried out by CAO in the Moscow park zone since 1991 and that characterize the surface ozone state in Central Russia are also considered. 相似文献
167.
Konstantinova N. P. Khanchuk A. I. Mikhailik P. E. Skolotnev S. G. Ivanova E. V. Bich A. S. Cherkashev G. A. 《Doklady Earth Sciences》2021,496(2):125-129
Doklady Earth Sciences - New data on the morphology, chemical composition, and age of the ferromanganese crusts of the Doldrums Fracture Zone, Central Atlantic, collected during the 45th cruise of... 相似文献
168.
Sapozhnikov A. N. Chukanov N. V. Shendrik R. Yu. Vigasina M. F. Tauson V. L. Lipko S. V. Belakovskiy D. I. Levitskii V. I. Suvorova L. F. Ivanova L. A. 《Geology of Ore Deposits》2022,64(7):470-475
Geology of Ore Deposits - The status of lazurite as a valid mineral species has been confirmed. The neotype specimen from the Malaya Bystraya gem lazurite deposit, Baikal Lake area has been studied... 相似文献
169.
Spiridonov E. M. Belyakov S. N. Ivanova Yu. A. Egorov K. V. Korotaeva N. N. Naumov D. I. Yapaskurt O. V. 《Geology of Ore Deposits》2022,64(7):495-502
Geology of Ore Deposits - Hibbingite, siderite, and their manganoan varieties replacing magnetite and associated sulfides are widespread in tectonized and metamorphosed pentlandite–putoranite... 相似文献
170.