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We give various conditions for the unique invertibility of the operator d/dt + A(t) in the space of functions bounded on the whole line. The methods we use essentially rely on the almost-periodicity of the operator-function A(t).Translated from Matematicheskie Zametki, Vol. 19, No. 1, pp. 99–104, January, 1976. 相似文献
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We prove the existence of a rank-one pseudotoric structure on an arbitrary smooth toric symplectic manifold. As a consequence, we propose a method for constructing Chekanov-type nonstandard Lagrangian tori on arbitrary toric manifolds. 相似文献
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P. G. Gagarin A. V. Tyurin V. N. Gus’kov A. V. Khoroshilov K. S. Gavrichev 《Russian Journal of Inorganic Chemistry》2018,63(11):1478-1483
The isobaric heat capacity of Tm2O3 · 2ZrO2 solid solution was measured by adiabatic calorimetry and differential scanning calorimetry (DSC), and smoothed values of the enthalpy changes, entropy, and reduced Gibbs free energy in the temperature range 8–1200 K were calculated. Thermal expansion was studied by X-ray diffraction in the temperature range 298–1173 K. 相似文献
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K. S. Gavrichev N. N. Smirnova M. A. Ryumin V. M. Gurevich A. V. Tyurin F. M. Spiridonov L. N. Komissarova V. P. Danilov 《Russian Journal of Inorganic Chemistry》2008,53(2):268-274
The heat capacities of Na2Tb(MoO4)(PO4) and K2Tb(MoO4)(PO4) were measured by adiabatic calorimetry at low temperatures (6.34–333.74 and 7.20–341.17 K, respectively). Smoothed thermal-capacities values were used to calculate the entropy, enthalpy increments, and reduced Gibbs energy. The respective values at 298.15 K are as follows: for Na2Tb(MoO4)(PO4), C p 0 (298.15 K) = 240.1 ± 0.2 J/(K mol), 0 (298.15 K) = 307.4 ± 0.4 J/(K mol), H 0(298.15 K) ? H 0(0) = 44.95 ± 0.03 kJ/mol, and Φ0(298.15 K) = 156.6 ± 0.5 J/(K mol); and for K2Tb(MoO4)(PO4): C p 0 (298.15 K) = 245.1 ± 0.1 J/(K mol), S 0(298.15 K) = 322.9 ± 0.1 J/(K mol), H 0(298.15 K) ? H 0(0) = 46.58 ± 0.02 kJ/mol, and Φ0(298.15 K) = 166.6 ± 0.2 J/(K mol). The noncooperative magnetic component of the heat capacity was estimated. 相似文献
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R. V. Tyurin A. P. Zadorozhnaya A. N. Antonov V. V. Mezheritskii 《Russian Journal of Organic Chemistry》2008,44(11):1657-1664
A capability was studied of hydrogenated α-pyrone heterocycle in 7-methoxy-4-(4-methoxy-phenyl)-3,4-dihydro-2H-benzo[h]chromen-2-one to undergo aminolysis under the treatment with hydrazine hydrate, primary and secondary aliphatic and aromatic amines. A new approach was developed to the preparation of perihydroxyketone of naphthalene series containing a specific functional substituent in the ortho-position with respect to hydroxy group. The effect was revealed of an acetyl group in the position 9 of 7-methoxy-4-(4-methoxyphenyl)-3,4-dihydro-2H-benzo[h]chromen-2-one on the reaction of this compound with aliphatic amines and hydrazine hydrate. 9-Methoxy-1-(4-methoxyphenyl)-6-methyl-3H-benzo[de]pyrido[3,2,1-if]cinnolin-3-one [9-methyl-6-methoxy-3-(4-methoxyphenyl)-10,10a-diazapyren-1-one] was obtained, a new bis-peri-fused heteroaromatic system. 相似文献