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81.
This paper performs a systematic study of some nonlinear integral equations with unknown lower limits of integration, which arise in economics, operations research, population biology and environmental sciences. A general investigation technique is developed for systems of such equations and several theorems about the existence and uniqueness of a solution are proven. The links to other functional equations with state-dependent delays are discussed. Applied interpretation of the obtained results is provided. 相似文献
82.
The first goal of this paper is to prove multiple asymptotic results for a time-discrete and space-continuous polymer model of a random walk in a random potential. These results include: existence of deterministic free energy density in the infinite-volume limit for every fixed asymptotic slope, concentration inequalities for free energy implying a bound on its fluctuation exponent, and straightness estimates implying a bound on the transversal fluctuation exponent. The culmination of this program is almost sure existence and uniqueness of polymer measures on one-sided infinite paths with given endpoint and slope, and interpretation of these infinite-volume Gibbs measures as thermodynamic limits. Moreover, we prove that marginals of polymer measures with the same slope and different endpoints are asymptotic to each other. The second goal of the paper is to develop ergodic theory of the Burgers equation with positive viscosity and random kick forcing on the real line without any compactness assumptions. Namely, we prove a one force–one solution principle, using the infinite-volume polymer measures to construct a family of stationary global solutions for this system, and proving that each of those solutions is a one-point pullback attractor on the initial conditions with the same spatial average. This provides a natural extension of the same program realized for the inviscid Burgers equation with the help of action minimizers that can be viewed as zero temperature limits of polymer measures. © 2018 Wiley Periodicals, Inc. 相似文献
83.
Kirill V. Zaitsev Yulia A. Piskun Yuri F. Oprunenko Sergey S. Karlov Galina S. Zaitseva Irina V. Vasilenko Andrei V. Churakov Sergei V. Kostjuk 《Journal of polymer science. Part A, Polymer chemistry》2014,52(9):1237-1250
The aluminum complexes containing two iminophenolate ligands of the type (p‐XC6H4NCHC6H4O‐o)2AlR' (R′=Me ( 3, 4 ) or R′=O(CH2)4OCH=CH2 ( 5, 6 ), X=H ( 3, 5 ), F( 4, 6 )) were synthesized and characterized by 1H, 13C NMR spectroscopy, and X‐ray crystallography. The reaction of AlMe3 with two equivalents of substituted iminophenols gave five‐coordinated {ONR}2AlMe ( 3, 4 ) complexes. Subsequent reaction of these methyl complexes with unsaturated alcohol, HO(CH2)4OCH=CH2, resulted in target compounds 5 and 6 in a good yield. It was shown that the complexes ( 3 ‐ 6 ) are monomeric in solution (NMR) and in solid state (X‐ray analysis). The catalytic activity of the complexes 5 and 6 towards ring‐opening polymerization (ROP) of ?‐caprolactone and d,l ‐lactide was assessed. Complex 5 showed higher activity as compared with 6 , while both of these catalysts induced controlled homo‐ and copolymerization to afford the macromonomers with high content of vinyl ether end groups (Fn > 80%) in a broad range of molecular weights (Mn = 4000–30,000 g mol?1) with relatively narrow MWD (Mw/Mn = 1.1–1.5). © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1237–1250 相似文献
84.
Rate constants of the reactions of O(3P) atoms with Br2 and NO2 over the temperature range 220-950 K
The kinetics of the reactions of Br2 and NO2 with ground state oxygen atoms have been studied over a wide temperature range, T = 220-950 K, using a low-pressure flow tube reactor coupled with a quadrupole mass spectrometer: O + NO2 → NO + O2 (1) and O + Br2 → Br + BrO (2). The rate constant of reaction (1) was determined under pseudo–first-order conditions, either monitoring the kinetics of O-atom or NO2 consumption in excess of NO2 or of the oxygen atoms, respectively: k1 = (6.1 ± 0.4) × 10−12 exp((155 ± 18)/T) cm3 molecule−1 s−1 (where the uncertainties represent precision at the 2σ level, the estimated total uncertainty on k1 being 15% at all temperatures). The temperature dependence of k1, found to be in excellent agreement with multiple previous low-temperature data, was extended to 950 K. The rate constant of reaction (2) determined under pseudo–first-order conditions, monitoring the kinetics of Br2 consumption in excess of O-atoms, showed upward curvature at low and high temperatures of the study and was fitted with the following three-parameter expression: k2 = 9.85 × 10−16 T1.41 exp(543/T) cm3 molecule−1 s−1 at T = (220-950) K, which is recommended from the present study with an independent of temperature conservative uncertainty of 15% on k2. 相似文献
85.
Nadezhda S. Temnyakova Dmitry A. Vasilenko Mstislav I. Lavrov Dmitry S. Karlov Yuri K. Grishin Vladimir L. Zamoyski Vladimir V. Grigoriev Elena B. Averina Vladimir A. Palyulin 《Mendeleev Communications》2021,31(2):219-220
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86.
87.
The modern intracavity laser method has been applied to study electronic spectra of the hafnium monohalides molecules. Results of new investigation of HfF and HfBr molecules are presented: the bands at 589.3, 590.6, and 593.1 nm observed in intracavity laser spectra of HfF4 have been assigned to the bands of HfF or ionized HfF; new molecular constants of the HfBr molecule have been obtained. Spectroscopic studies of HfCl and Hfl molecules are discussed, and the most reliable molecular constants of HfCl, HfBr, and Hfl molecules are recommended. 相似文献
88.
Russell Johnson Yuri Latushkin Roland Schnaubelt 《Journal of Dynamics and Differential Equations》2014,26(2):243-266
We prove the reduction principle and study other attractivity properties of the center and center-unstable manifolds in the vicinity of a steady-state solution for quasilinear systems of parabolic partial differential equations with fully nonlinear boundary conditions on bounded or exterior domains. 相似文献
89.
Oleg G. Sinyashin Irina P. Romanova Gulshat G. Yusupova Valery I. Kovalenko Yuri Y. Efremov Irina I. Vandyukova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract Data on the structure of cycloadducts of organophosphorus dipolar reagents and fullerenes arc absent, to our knowledge. We died the reactions and the shucturc of cycloadducts of phosphorylated azidcs and nitrile oxide with [60]fullcrcnc. The cycloaddition of diphcnylphosphinic llzide to fullcrme has bcm determined to lead to the 1 -[(N-diphenylphosphoryl)amino]-2-hydroxy[6O]hllcrme (l), the mixhuc of phosphorylated aziridinofullcrcne (2) and derivative of fullerne (3) with one aziridine fragment and one aminohydmxy-fragment, or to product (4), depending on the conditions of don . 相似文献
90.
Elena B. Averina Yuri V. Samoilichenko Yulia A. Volkova Yuri K. Grishin Victor B. Rybakov Andrei G. Kutateladze Mikhail E. Elyashberg Tamara S. Kuznetsova Nikolai S. Zefirov 《Tetrahedron letters》2012,53(12):1472-1475
Revised regiochemistry for the heterocyclization of electrophilic alkenes with tetranitromethane (TNM) in the presence of triethylamine, providing rapid access to nitroisoxazoles, is reported. The formation of 5-nitroisoxazoles previously incorrectly assigned as 3-nitro regioisomers, has now been established unambiguously by X-ray crystallography. Empirical computations with ACD/CNMR Predictor, based both on hierarchical ordering of spherical environments (HOSE) and an algorithm of artificial neural networks (ANN), and also Density Functional Theory computations of the 13C NMR chemical shifts for the 3- versus 5-nitroisoxazoles are shown to consistently match the spectra of the experimentally observed 5-regioisomers. 相似文献