2,132 research outputs found
New evidence of the nonglaciated development of the northern part of the Western Siberian lowland in the Quaternary period
To solve the controversially debated problem related to the areal extent of the ice sheet in Western Siberia in the Quaternary period, we have studied the development of cold born objects of this area estimating the relationships between them in terms of cryogenic diversity. We have obtained a field of new cross data related to the development of cryogenic and glacial phenomena, their relationship, and traces they left. The research showed that, in this area, the trend of rock freezing is clearly reflected in the Quaternary formations, but there were no conditions for ice sheet development even during the cryochrons
Morphological record of pedogenesis and landscape evolution in the upper quaternary pedosediments within the upper Volga river basin
The morphological record of pedogenesis (mostly at a micromorphological scale) and the features of paleosols developed at the northern geographical extremity of the MIS3 paleopedoshpere (including the Bryansk fossil soils) are described. The profiles of the MIS3 paleosols (dark humic gley and peaty gley with the14Π‘-age around 29-50 cal kyr BP) are located within the periglacial zone in the centre of the Russian Plain (56.7Β°-58.5Β° N) within the Upper Volga drainage basin. An assemblage of stable micromorphological features of paleosols studied includes the following: 1) ferruginous nodules and other pedofeatures, occasionally fragmented; 2) concentration (separation) of sand grains within certain microzones; 3) inclusions of raw organic matter, often deformed and oriented to different degrees within the matrix. Despite being buried for a long time period and superimposed by the Holocene pedogenetic processes (clay illuviation), the paleosols preserve some features of short-term (101-102 yr) and medium-term (102-103-4 yr) elementary pedogenetic processes (EPP). The short-term EPP include gleying, structure forming and cryogenic processes. The medium-term EPP include humus formation, peat formation and organic matter accumulation. A hypothesis of cryogenic formation of the paleosols studied is substantiated. Only an almost impermeable layer of permafrost could cause water-logging and gleying in these geological and geomorphological conditions
Low-Mass Star Formation, Triggered by Supernova in Primordial Clouds
The evolution of a gas shell, swept by the supernova remnant of a massive
first generation star, is studied with H_2 and HD chemistry taken into account.
When a first-generation star explodes as a supernova, H_2 and HD molecules are
formed in the swept gas shell and effectively cool the gas shell to
temperatures of 32 K - 154 K. If the supernova remnant can sweep to gather the
ambient gas, the gas shell comes to be dominated by its self-gravity, and
hence, is expected to fragment. Our result shows that for a reasonable range of
temperatures (200 K - 1000 K) of interstellar gas, the formation of
second-generation stars can be triggered by a single supernova or hypernova.Comment: 38pages, 10 figures, The Astrophysical Journal, accepted 8 Dec. 200
Breeding columnar apple-tree cultivars for supercompact growth habit
This work was based on the combinatorial breeding technique using donors of the columnar growth type (Co gene), sources of winter hardiness and high consumer qualities, and scab immunity donors (Rvi6 gene). The selection in the columnar apple-tree hybrid progeny was accompanied by the assessment of growth vigor, compactness degree, and seedling cultivability in accordance with the guidelines.Due to the increasing popularity of apple trees with the columnar crown type, the volume of breeding work for columnar growthΒ habitΒ atΒ theΒ RussianΒ ResearchΒ InstituteΒ ofΒ FruitΒ CropΒ BreedingΒ (VNIISPK)Β overΒ theΒ pastΒ 9 yearsΒ amountedΒ to 133,582 flowers, or one third of the entire hybridization envisaged by the apple-tree breeding program. Meticulous selection of parent forms is carried out in order to incorporate a set of useful traits in the columnar growth habit genotype. Both cultivars and hybrid forms serve as sources and donors of the traits interesting for breeders. All the studied cultivars released by VNIISPK are dwarf: their height is within the range from 287 cm (cv. βPriokskoeβ) to 198 cm (cv. βOrlovskaya Yeseniaβ), and they can be recommended for both commercial plantations and amateur gardens. The columnar form 34-34-98 is characterized by a unique degree of compactness (the ratio of the internode length to the shoot diameter) equal to 0.4 versus the average value of 1.6 for this indicator in the studied columnar cultivars. This form was involved in the release of 78 promising hybrid seedlings, the best of which (38.5%) were transferred to the garden for primary variety trials. A large yield of seedlings characterized by high compactness in the progeny of the columnar apple tree 34-34-98 makes it possible to recommend it for the development of new apple-tree genotypes for highly cost-effective orchards with high tree planting density
The Supernova Triggered Formation and Enrichment of Our Solar System
We investigate the enrichment of the pre-solar cloud core with short lived
radionuclides (SLRs), especially 26Al. The homogeneity and the surprisingly
small spread in the ratio 26Al/27Al observed in the overwhelming majority of
calcium-aluminium-rich inclusions (CAIs) in a vast variety of primitive
chondritic meteorites places strong constraints on the formation of the the
solar system. Freshly synthesized radioactive 26Al has to be included and well
mixed within 20kyr. After discussing various scenarios including X-winds, AGB
stars and Wolf-Rayet stars, we come to the conclusion that triggering the
collapse of a cold cloud core by a nearby supernova is the most promising
scenario. We then narrow down the vast parameter space by considering the
pre-explosion survivability of such a clump as well as the cross-section
necessary for sufficient enrichment. We employ numerical simulations to address
the mixing of the radioactively enriched SN gas with the pre-existing gas and
the forced collapse within 20kyr. We show that a cold clump of 10Msun at a
distance of 5pc can be sufficiently enriched in 26Al and triggered into
collapse fast enough - within 18kyr after encountering the supernova shock -
for a range of different metallicities and progenitor masses, even if the
enriched material is assumed to be distributed homogeneously in the entire
supernova bubble. In summary, we envision an environment for the birth place of
the Solar System 4.567Gyr ago similar to the situation of the pillars in M16
nowadays, where molecular cloud cores adjacent to an HII region will be hit by
a supernova explosion in the future. We show that the triggered collapse and
formation of the Solar System as well as the required enrichment with
radioactive 26Al are possible in this scenario.Comment: 12 pages, 8 figures, accepted for publication in ApJ. Resolution of
most figures degraded to fit within arXiv size limits. A full resolution
version is available at
http://www.usm.uni-muenchen.de/~gritschm/Gritschneder_2011_sun.pd
Fractional Variations for Dynamical Systems: Hamilton and Lagrange Approaches
Fractional generalization of an exterior derivative for calculus of
variations is defined. The Hamilton and Lagrange approaches are considered.
Fractional Hamilton and Euler-Lagrange equations are derived. Fractional
equations of motion are obtained by fractional variation of Lagrangian and
Hamiltonian that have only integer derivatives.Comment: 21 pages, LaTe
Coronal mass ejections as expanding force-free structures
We mode Solar coronal mass ejections (CMEs) as expanding force-fee magnetic
structures and find the self-similar dynamics of configurations with spatially
constant \alpha, where {\bf J} =\alpha {\bf B}, in spherical and cylindrical
geometries, expanding spheromaks and expanding Lundquist fields
correspondingly. The field structures remain force-free, under the conventional
non-relativistic assumption that the dynamical effects of the inductive
electric fields can be neglected. While keeping the internal magnetic field
structure of the stationary solutions, expansion leads to complicated internal
velocities and rotation, induced by inductive electric field. The structures
depends only on overall radius R(t) and rate of expansion \dot{R}(t) measured
at a given moment, and thus are applicable to arbitrary expansion laws. In case
of cylindrical Lundquist fields, the flux conservation requires that both axial
and radial expansion proceed with equal rates. In accordance with observations,
the model predicts that the maximum magnetic field is reached before the
spacecraft reaches the geometric center of a CME.Comment: 19 pages, 9 Figures, accepted by Solar Physic
ΠΠΎΠ΄Π³ΠΎΡΠΎΠ²ΠΊΠ° ΠΊ Π°Π½Π΅ΡΡΠ΅Π·ΠΈΠΈ Π±ΠΎΠ»ΡΠ½ΡΡ Ρ ΡΠΎΠΏΡΡΡΡΠ²ΡΡΡΠ΅ΠΉ ΠΏΠ°ΡΠΎΠ»ΠΎΠ³ΠΈΠ΅ΠΉ Π»Π΅Π³ΠΊΠΈΡ ΠΈ Π²ΡΡΠΎΠΊΠΈΠΌ ΡΠΈΡΠΊΠΎΠΌ ΡΠ°Π·Π²ΠΈΡΠΈΡ ΠΏΠΎΡΠ»Π΅ΠΎΠΏΠ΅ΡΠ°ΡΠΈΠΎΠ½Π½ΡΡ Π»Π΅Π³ΠΎΡΠ½ΡΡ ΠΎΡΠ»ΠΎΠΆΠ½Π΅Π½ΠΈΠΉ
The objective:Β basing on published data, to highlight the main issues of preparation of patients with concomitant lung pathology and a high risk of developing postoperative pulmonary complications for planned surgical interventions.Results:Β changes made to international guidelines over the past 5 years based on evidence-based studies and meta-analyzes have been analyzed. The article presents data on preoperative management of patients with concomitant lung pathologies and a high risk of postoperative pulmonary complications, assessment of the risk of developing these complications based on evaluation of the functional status of patients. It analyzes the contemporary recommendations on the perioperative prevention of pulmonary complications, the use of physical exercises and respiratory gymnastics in the perioperative period in patients with a high risk of postoperative pulmonary complications. It is concluded that the implementation of comprehensive strategy aimed at reducing the risk of pulmonary complications should ensure decrease in their frequency and mortality due to them.Π¦Π΅Π»Ρ:Β Π½Π° ΠΎΡΠ½ΠΎΠ²Π°Π½ΠΈΠΈ Π΄Π°Π½Π½ΡΡ
Π»ΠΈΡΠ΅ΡΠ°ΡΡΡΡ ΠΎΡΠ²Π΅ΡΠΈΡΡ ΠΎΡΠ½ΠΎΠ²Π½ΡΠ΅ ΠΏΠΎΠ»ΠΎΠΆΠ΅Π½ΠΈΡ ΠΏΡΠΎΠ±Π»Π΅ΠΌΡ ΠΏΠΎΠ΄Π³ΠΎΡΠΎΠ²ΠΊΠΈ ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΎΠ² Ρ ΡΠΎΠΏΡΡΡΡΠ²ΡΡΡΠ΅ΠΉ ΠΏΠ°ΡΠΎΠ»ΠΎΠ³ΠΈΠ΅ΠΉ Π»Π΅Π³ΠΊΠΈΡ
ΠΈ Π²ΡΡΠΎΠΊΠΈΠΌ ΡΠΈΡΠΊΠΎΠΌ ΡΠ°Π·Π²ΠΈΡΠΈΡ ΠΏΠΎΡΠ»Π΅ΠΎΠΏΠ΅ΡΠ°ΡΠΈΠΎΠ½Π½ΡΡ
Π»Π΅Π³ΠΎΡΠ½ΡΡ
ΠΎΡΠ»ΠΎΠΆΠ½Π΅Π½ΠΈΠΉ ΠΊ ΠΏΠ»Π°Π½ΠΎΠ²ΡΠΌ ΠΎΠΏΠ΅ΡΠ°ΡΠΈΠ²Π½ΡΠΌ Π²ΠΌΠ΅ΡΠ°ΡΠ΅Π»ΡΡΡΠ²Π°ΠΌ.Π Π΅Π·ΡΠ»ΡΡΠ°ΡΡ:Β Π²ΡΠΏΠΎΠ»Π½Π΅Π½ Π°Π½Π°Π»ΠΈΠ· ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΠΉ, Π²Π½Π΅ΡΠ΅Π½Π½ΡΡ
Π² ΠΌΠ΅ΠΆΠ΄ΡΠ½Π°ΡΠΎΠ΄Π½ΡΠ΅ ΠΊΠ»ΠΈΠ½ΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΡΠ΅ΠΊΠΎΠΌΠ΅Π½Π΄Π°ΡΠΈΠΈ Π·Π° ΠΏΠΎΡΠ»Π΅Π΄Π½ΠΈΠ΅ 5 Π»Π΅Ρ Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ Π΄ΠΎΠΊΠ°Π·Π°ΡΠ΅Π»ΡΠ½ΡΡ
ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΠΉ ΠΈ ΠΌΠ΅ΡΠ°Π°Π½Π°Π»ΠΈΠ·ΠΎΠ². ΠΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½Ρ Π΄Π°Π½Π½ΡΠ΅ Π² ΠΎΡΠ½ΠΎΡΠ΅Π½ΠΈΠΈ Π²Π΅Π΄Π΅Π½ΠΈΡ Π² ΠΏΡΠ΅Π΄ΠΎΠΏΠ΅ΡΠ°ΡΠΈΠΎΠ½Π½ΠΎΠΌ ΠΏΠ΅ΡΠΈΠΎΠ΄Π΅ Π±ΠΎΠ»ΡΠ½ΡΡ
Ρ ΡΠΎΠΏΡΡΡΡΠ²ΡΡΡΠ΅ΠΉ ΠΏΠ°ΡΠΎΠ»ΠΎΠ³ΠΈΠ΅ΠΉ Π»Π΅Π³ΠΊΠΈΡ
ΠΈ Π²ΡΡΠΎΠΊΠΈΠΌ ΡΠΈΡΠΊΠΎΠΌ ΠΏΠΎΡΠ»Π΅ΠΎΠΏΠ΅ΡΠ°ΡΠΈΠΎΠ½Π½ΡΡ
Π»Π΅Π³ΠΎΡΠ½ΡΡ
ΠΎΡΠ»ΠΎΠΆΠ½Π΅Π½ΠΈΠΉ, ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ ΡΠΈΡΠΊΠ° ΡΠ°Π·Π²ΠΈΡΠΈΡ ΡΡΠΈΡ
ΠΎΡΠ»ΠΎΠΆΠ½Π΅Π½ΠΈΠΉ Π½Π° ΠΎΡΠ½ΠΎΠ²Π΅ ΠΎΡΠ΅Π½ΠΊΠΈ ΡΡΠ½ΠΊΡΠΈΠΎΠ½Π°Π»ΡΠ½ΠΎΠ³ΠΎ ΡΡΠ°ΡΡΡΠ° Π±ΠΎΠ»ΡΠ½ΡΡ
. ΠΡΠΎΠ°Π½Π°Π»ΠΈΠ·ΠΈΡΠΎΠ²Π°Π½Ρ ΡΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΡΠ΅ ΡΠ΅ΠΊΠΎΠΌΠ΅Π½Π΄Π°ΡΠΈΠΈ ΠΏΠΎ ΠΏΠ΅ΡΠΈΠΎΠΏΠ΅ΡΠ°ΡΠΈΠΎΠ½Π½ΠΎΠΉ ΠΏΡΠΎΡΠΈΠ»Π°ΠΊΡΠΈΠΊΠ΅ Π»Π΅Π³ΠΎΡΠ½ΡΡ
ΠΎΡΠ»ΠΎΠΆΠ½Π΅Π½ΠΈΠΉ, ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΡ ΡΠΈΠ·ΠΈΡΠ΅ΡΠΊΠΈΡ
ΡΠΏΡΠ°ΠΆΠ½Π΅Π½ΠΈΠΉ ΠΈ Π΄ΡΡ
Π°ΡΠ΅Π»ΡΠ½ΠΎΠΉ Π³ΠΈΠΌΠ½Π°ΡΡΠΈΠΊΠΈ Π² ΠΏΠ΅ΡΠΈΠΎΠΏΠ΅ΡΠ°ΡΠΈΠΎΠ½Π½ΠΎΠΌ ΠΏΠ΅ΡΠΈΠΎΠ΄Π΅ Ρ Π±ΠΎΠ»ΡΠ½ΡΡ
Ρ Π²ΡΡΠΎΠΊΠΈΠΌ ΡΠΈΡΠΊΠΎΠΌ ΠΏΠΎΡΠ»Π΅ΠΎΠΏΠ΅ΡΠ°ΡΠΈΠΎΠ½Π½ΡΡ
Π»Π΅Π³ΠΎΡΠ½ΡΡ
ΠΎΡΠ»ΠΎΠΆΠ½Π΅Π½ΠΈΠΉ. Π‘Π΄Π΅Π»Π°Π½ Π²ΡΠ²ΠΎΠ΄, ΡΡΠΎ ΠΏΡΠ°ΠΊΡΠΈΡΠ΅ΡΠΊΠ°Ρ ΡΠ΅Π°Π»ΠΈΠ·Π°ΡΠΈΡ ΠΊΠΎΠΌΠΏΠ»Π΅ΠΊΡΠ½ΠΎΠΉ ΡΡΡΠ°ΡΠ΅Π³ΠΈΠΈ, Π½Π°ΠΏΡΠ°Π²Π»Π΅Π½Π½ΠΎΠΉ Π½Π° ΡΠ½ΠΈΠΆΠ΅Π½ΠΈΠ΅ ΡΠΈΡΠΊΠ° Π»Π΅Π³ΠΎΡΠ½ΡΡ
ΠΎΡΠ»ΠΎΠΆΠ½Π΅Π½ΠΈΠΉ, Π΄ΠΎΠ»ΠΆΠ½Π° ΠΎΠ±Π΅ΡΠΏΠ΅ΡΠΈΡΡ ΡΠ½ΠΈΠΆΠ΅Π½ΠΈΠ΅ ΠΈΡ
ΡΠ°ΡΡΠΎΡΡ ΠΈ ΠΎΠ±ΡΡΠ»ΠΎΠ²Π»Π΅Π½Π½ΡΡ ΠΈΠΌΠΈ Π»Π΅ΡΠ°Π»ΡΠ½ΠΎΡΡΡ
Use of different types of active carbons in adsorption process of precious metals
In the article the different types of activated carbons for using in adsorption process of precious metals from solution leaching is considered. Brand industrial sorbents possessing better sorption properties are considered. One of the types of carbon sorbents is revealed by the example of one way of increasing the sorption capacity of the manufacturing process.Π ΡΠ°Π±ΠΎΡΠ΅ ΡΠ°ΡΡΠΌΠΎΡΡΠ΅Π½Ρ ΡΠ°Π·Π½ΡΠ΅ Π²ΠΈΠ΄Ρ Π°ΠΊΡΠΈΠ²ΠΈΡΠΎΠ²Π°Π½Π½ΡΡ
ΡΠ³Π»Π΅ΠΉ Π΄Π»Ρ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΡ Π² ΠΏΡΠΎΡΠ΅ΡΡΠ΅ Π°Π΄ΡΠΎΡΠ±ΡΠΈΠΈ Π΄ΡΠ°Π³ΠΎΡΠ΅Π½Π½ΡΡ
ΠΌΠ΅ΡΠ°Π»Π»ΠΎΠ² ΠΈΠ· ΡΠ°ΡΡΠ²ΠΎΡΠΎΠ² Π²ΡΡΠ΅Π»Π°ΡΠΈΠ²Π°Π½ΠΈΡ. ΠΠΎΠΊΠ°Π·Π°Π½Ρ ΠΌΠ°ΡΠΊΠΈ ΠΏΡΠΎΠΌΡΡΠ»Π΅Π½Π½ΡΡ
ΡΠΎΡΠ±Π΅Π½ΡΠΎΠ², ΠΎΠ±Π»Π°Π΄Π°ΡΡΠΈΠ΅ Π½Π°ΠΈΠ»ΡΡΡΠΈΠΌΠΈ ΡΠΎΡΠ±ΡΠΈΠΎΠ½Π½ΡΠΌΠΈ ΡΠ²ΠΎΠΉΡΡΠ²Π°ΠΌΠΈ. ΠΡΡΠ²Π»Π΅Π½ ΠΎΠ΄ΠΈΠ½ ΠΈΠ· ΠΏΡΡΠ΅ΠΉ ΠΏΠΎΠ²ΡΡΠ΅Π½ΠΈΡ ΡΠΎΡΠ±ΡΠΈΠΎΠ½Π½ΠΎΠΉ ΡΠΏΠΎΡΠΎΠ±Π½ΠΎΡΡΠΈ Π² ΠΏΡΠΎΡΠ΅ΡΡΠ΅ ΠΏΡΠΎΠΈΠ·Π²ΠΎΠ΄ΡΡΠ²Π° Π½Π° ΠΏΡΠΈΠΌΠ΅ΡΠ΅ ΠΎΠ΄Π½ΠΎΠ³ΠΎ ΠΈΠ· Π²ΠΈΠ΄ΠΎΠ² ΡΠ³Π»Π΅ΡΠΎΠ΄Π½ΡΡ
ΡΠΎΡΠ±Π΅Π½ΡΠΎΠ²
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