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181.
Glaser T Liratzis I Kataeva O Fröhlich R Piacenza M Grimme S 《Chemical communications (Cambridge, England)》2006,(9):1024-1026
Two hydrogen-bonds from geometrically constrained OH groups to coordinated oxygen donors shift the reduction potential of a Cu(II) complex by +270 mV as compared to the structurally analogous reference complex missing the OH groups. 相似文献
182.
Kinetic studies on the gas-phase reactions of OH and NO3 radicals and ozone with ethyl vinyl ether (EVE), propyl vinyl ether (PVE) and butyl vinyl ether (BVE) have been performed in a 405 L borosilicate glass chamber at 298 +/- 3 K in synthetic air using in situ FTIR spectroscopy to monitor the reactants. Using a relative kinetic method rate coefficients (in units of cm3 molecule(-1) s(-1)) of (7.79 +/- 1.71) x 10(-11), (9.73 +/- 1.94) x 10(-11) and (1.13 +/- 0.31) x 10(-10) have been obtained for the reaction of OH with EVE, PVE and BVE, respectively, (1.40 +/- 0.35) x 10(-12), (1.85 +/- 0.53) x 10(-12) and (2.10 +/- 0.54) x 10(-12) for the reaction of NO3 with EVE, PVE and BVE, respectively, and (2.06 +/- 0.42) x 10(-16), (2.34 +/- 0.48) x 10(-16) and (2.59 +/- 0.52) x 10(-16) for the ozonolysis of EVE, PVE and BVE, respectively. Tropospheric lifetimes of EVE, PVE and BVE with respect to the reactions with reactive tropospheric species (OH, NO3 and O3) have been estimated for typical OH and NO3 radical and ozone concentrations. 相似文献
183.
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185.
Thomas Bonesky Stephan Dahlke Peter Maass Thorsten Raasch 《Advances in Computational Mathematics》2010,33(4):385-411
This paper is concerned with the numerical treatment of inverse heat conduction problems. In particular, we combine recent
results on the regularization of ill-posed problems by iterated soft shrinkage with adaptive wavelet algorithms for the forward
problem. The analysis is applied to an inverse parabolic problem that stems from the industrial process of melting iron ore
in a steel furnace. Some numerical experiments that confirm the applicability of our approach are presented. 相似文献
186.
Gromov–Witten invariants of weighted projective planes and Euler characteristics of moduli spaces of representations of bipartite quivers are related via the tropical vertex, a group of formal automorphisms of a torus. On the Gromov–Witten side, this uses the work of Gross, Pandharipande and Siebert. The quiver moduli side features quiver wall-crossing formulas, functional equations for Euler characteristics, and localization techniques. We derive several explicit formulas for Gromov–Witten invariants. 相似文献
187.
We study Newton type methods for inverse problems described by nonlinear operator equations $F(u)=g$ in Banach spaces where the Newton equations $F^{\prime }(u_n;u_{n+1}-u_n) = g-F(u_n)$ are regularized variationally using a general data misfit functional and a convex regularization term. This generalizes the well-known iteratively regularized Gauss–Newton method (IRGNM). We prove convergence and convergence rates as the noise level tends to $0$ both for an a priori stopping rule and for a Lepski?-type a posteriori stopping rule. Our analysis includes previous order optimal convergence rate results for the IRGNM as special cases. The main focus of this paper is on inverse problems with Poisson data where the natural data misfit functional is given by the Kullback–Leibler divergence. Two examples of such problems are discussed in detail: an inverse obstacle scattering problem with amplitude data of the far-field pattern and a phase retrieval problem. The performance of the proposed method for these problems is illustrated in numerical examples. 相似文献
188.
189.
We give a complete derived equivalence classification of all nonstandard representation-infinite domestic selfinjective algebras over an algebraically closed field. As a consequence, a complete stable equivalence classification of these algebras is obtained. 相似文献
190.
Saner Poplata Dr. Andreas Bauer Dr. Golo Storch Prof. Dr. Thorsten Bach 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(34):8135-8148
The intramolecular [2+2] photocycloaddition of 3-alkenyl-2-cycloalkenones was performed in an enantioselective fashion (nine representative examples, 54–86 % yield, 76–96 % ee) upon irradiation at λ=366 nm in the presence of an AlBr3-activated oxazaborolidine as the Lewis acid. An extensive screening of proline-derived oxazaborolidines showed that the enantioface differentiation depends strongly on the nature of the aryl group at the 3-position of the heterocycle. DFT calculations of the Lewis acid–substrate complex indicate that attractive dispersion forces may be responsible for a change of the binding mode. The catalytic [2+2] photocycloaddition was shown to proceed on the triplet hypersurface with a quantum yield of 0.05. The positive effect of Lewis acids on the outcome of a given intramolecular [2+2] photocycloaddition was illustrated by optimizing the key step in a concise total synthesis of the sesquiterpene (±)-italicene. 相似文献