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排序方式: 共有420条查询结果,搜索用时 31 毫秒
411.
412.
Nesmeyanov A. N. Yur'eva L. P. Zaitseva N. N. Latov V. K. Soinov S. D. Samoilenko L. M. Babievskii K. K. Makarovskaya A. G. 《Russian Chemical Bulletin》1976,25(4):903-905
Russian Chemical Bulletin - 相似文献
413.
B. L. Korsunskii N. G. Samoilenko E. V. Deyun A. O. Il’chenko 《Russian Journal of Physical Chemistry B, Focus on Physics》2008,2(3):426-430
A continued stirred-tank reactor with an exothermic autocatalytic reaction running in it is modeled. In contrast to the simple kinetic law formulated in terms of a first-order equation, a variety of possible types of thermal isoclines, including isoles, are found for the autocatalytic process in the dimensionless “degree of conversion-temperature” coordinates. A bifurcation curve separating the domains of existence of one and three steady states is constructed in the Se-Da coordinates. 相似文献
414.
We study sets
there exist n projectors P1,...,Pn such that
. We prove that if n 6, then
. 相似文献
415.
416.
We obtain asymptotic representations as t ↑ ω, ω ≤ + ∞, for all possible types of P
ω(Y
0, λ
0)-solutions (where Y
0 is zero or ±∞ and −∞ ≤ λ0 ≤ +∞) of nonlinear differential equations y
(n) = α
0
p(t)φ(y), where α
0 ∈ {−1, 1}, p: [a, ω[→]0,+∞[ is a continuous function, and φ is a continuous regularly varying function in a one-sided neighborhood of Y
0. 相似文献
417.
O. P. Yushchenko V. F. Kurshetsov A. P. Filin S. A. Akimenko A. V. Artamonov A. M. Blik V. V. Brekhovskikh V. S. Burtovoy S. V. Donskov A. V. Inyakin A. M. Gorin G. V. Khaustov S. A. Kholodenko V. N. Kolosov A. S. Konstantinov V. M. Leontiev V. A. Lishin M. V. Medynsky Yu. V. Mikhailov V. F. Obraztsov V. A. Polyakov A. V. Popov V. I. Romanovsky V. I. Rykalin A. S. Sadovsky V. D. Samoilenko V. K. Semenov O. V. Stenyakin O. G. Tchikilev V. A. Uvarov V. A. Duk S. N. Filippov E. N. Guschin Yu. G. Kudenko A. A. Khudyakov V. I. Kravtsov A. Yu. Polyarush V. N. Bychkov G. D. Kekelidze V. M. Lysan B. Zh. Zalikhanov 《JETP Letters》2018,107(3):139-142
Recent results from OKA setup concerning form factor studies in Ke3 decay are presented. About 5.25 M events obtained for decays of 17.7 GeV/cK+ are selected for the analysis. The linear and quadratic slopes for the decay form factor f+(t) are measured: λ'+ = 2.95 ± 0.022 ± 0.018 × 10 -2 for the linear slope fit and λ+ = 2.611 ± 0.035 ± 0.028 × 10 -2, λ"+ = 1.91 ± 0.19 ± 0.14 × 10 -3 for the quadratic one. The scalar and tensor contributions are compatible with zero. Several alternative parametrizations are tried: the Pole fit parameter is found to be M V = 891 ± 3 MeV; the parameter of the dispersive parametrization is measured to be Λ+ = 2.458 ± 0.018 × 10-2. 相似文献
418.
V. D. Okunev Z. A. Samoilenko R. Szymczak H. Szymczak A. Szewczyk A. Malinowski J. Więckowski M. Wolny-Marszałek M. Ježabek I. A. Antoshina 《Journal of Experimental and Theoretical Physics》2018,126(6):784-801
The contribution of clusters of different sizes to magnetism and the switching of electron scattering mechanisms in amorphous Fe67Cr18B15 alloy during ion Ar+ irradiation is studied. The cluster magnetism is found to be related to the presence of clusters of the following two types: large α-(Fe, Cr) clusters of size D = 150–250 Å and small (D = 40–80 Å) clusters in a random intercluster medium. The generation of small ferromagnetic and antiferromagnetic clusters during ion irradiation leads to the formation of cluster glass, which affects the electrical properties of the alloy and causes a magnetic frustration. The temperature dependence of the barrier height is shown to characterize the magnetic state of the alloy in low fields. On the whole, the temperature dependence of the order parameter is a universal characteristic of the system. The temperature dependence of resistivity of initial alloys in the temperature range 98–300 K (ρ(T) ∝ T2) is determined by electron scattering by quantum defects, and the transition into a ferromagnetic state is revealed when the derivative ?ρ/?T ∝ T is analyzed. The increase in resistivity and the relation ρ ∝ T1/2 in strongly inhomogeneous samples after irradiation at a dose Φ = 1.5 × 1018 ions/cm2 are caused by weak localization effects, and the transition to a ferromagnetic state becomes obvious when the derivative ?ρ/?T ∝ T–1/2 is considered. Irradiation by fluence Φ = 3 × 1018 ions/cm2 induces a giant (twofold) increase in the alloy density, restores the ferromagnetism of large clusters, decreases the resistivity by 37%, and restores the relation ρ(T) ∝ T2, which results from the overlapping of the irradiation-induced small clusters when their concentration increases and from an increase in the alloy density. The overlapping of clusters lowers the barrier height and decreases the sensitivity of the alloy to an applied field. The relation ρ(T) ∝ T2 is valid for the entire temperature range T = 2–300 K because of the partial screening of the magnetic moments of large clusters by a medium having the properties of cluster glass. 相似文献
419.
420.
Dr. David O. Guarin Sameer M. Joshi Anna Samoilenko Mohammad S. H. Kabir Erin E. Hardy Dr. Atsush M. Takahashi Prof. Jan H. Ardenkjaer-Larsen Prof. Eduard Y. Chekmenev Dr. Yi-Fen Yen 《Angewandte Chemie (International ed. in English)》2023,62(31):e202219181
We report dissolution Dynamic Nuclear Polarization (d-DNP) of [15N3]metronidazole ([15N3]MNZ) for the first time. Metronidazole is a clinically approved antibiotic, which can be potentially employed as a hypoxia-sensing molecular probe using 15N hyperpolarized (HP) nucleus. The DNP process is very efficient for [15N3]MNZ with an exponential build-up constant of 13.8 min using trityl radical. After dissolution and sample transfer to a nearby 4.7 T Magnetic Resonance Imaging scanner, HP [15N3]MNZ lasted remarkably long with T1 values up to 343 s and 15N polarizations up to 6.4 %. A time series of HP [15N3]MNZ images was acquired in vitro using a steady state free precession sequence on the 15NO2 peak. The signal lasted over 13 min with notably long T2 of 20.5 s. HP [15N3]MNZ was injected in the tail vein of a healthy rat, and dynamic spectroscopy was performed over the rat brain. The in vivo HP 15N signals persisted over 70 s, demonstrating an unprecedented opportunity for in vivo studies. 相似文献