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1.
Jaroslaw A. Jelen 《Numerical Methods for Partial Differential Equations》1994,10(1):85-101
A new multidomain direct (noniterative) method for solving boundary-value problems is presented. Using this method, the solution is expressed by a linear combination of auxiliary functions and unknowns which pertain to the boundaries of a subdomain. This approach enables us to solve problems independently and exactly, without any iterations between subdomains. As a consequence, different types of equations and coordinate systems may be considered in different subdomains. Moreover, different boundary conditions and variable (in space) time steps may be imposed on the subdomains as well. Applications are given for initial boundary-value problems with known analytical solutions, including a highly nonlinear porosity equation. © 1994 John Wiley & Sons, Inc. 相似文献
2.
Ladislav Pesek Leszek A. Dobrzanski Pavol Zubko Jaroslaw Konieczny 《Journal of magnetism and magnetic materials》2006
The paper presents mechanical properties of two kinds of Co-based and one Fe-based metallic ribbons by the depth sensing indentation (DSI) technique. Investigations were carried out on two kinds ternary alloy Co77Si11,5B11,5 and Fe78Si13B9 and multicomponent Co68Fe4Mo1Si13,5B13,5, which are so-called “zero-magnetostriction” materials. Metallic ribbons were investigated in amorphous state and partially crystallized state after annealing in 400°C in argon atmosphere. Heating of ribbons obtained by melt spinning technique was performed to check its effect on changes of mechanical properties. 相似文献
3.
The efficient degradation of to the α-methylene ketone is described. Compound was then converted to the allylic alcohol - the precursor of vitamin D3 relatives. 相似文献
4.
Adam S. Plaziak Jaroslaw Spychala Hanna Wjtowicz Jerzy J. Langer Halina Thiel-Pawlicka Krzysztof Golankiewicz 《Journal of mass spectrometry : JMS》1992,27(11):1293-1298
Ortho-. meta- and para-isomers of N-(pyrimidin-4-yl)aminobenzoic acid and their methyl esters were investigated by electron impact mass Spectrometry. Their fragmentation was found to be strongly dependent on the position of the substituent in the aminobenzoic moiety. Two different kinds of ortho effect were studied and confirmed with the aid of deuterium-labelled derivatives. 相似文献
5.
Rode MF Roszak S Szymczak JJ Sadlej J Leszczynski J 《The Journal of chemical physics》2004,121(13):6277-6281
The results of the theoretical study of ground state potential energy surfaces for the chlorine-acetonitrile anion and its photodetachment product are presented. The shallow potential surfaces allow for the nondefinitive position of the chlorine within the complex. The dissociation energy of the neutral complex, estimated through the thermodynamic cycle, indicates significant structural changes due to the photodetachment process. The excess negative charge is localized mostly on the chlorine atom, and the electron detachment proceeds as an electron is removed from chlorine. The process leads to drastic changes in the electrostatic interactions within the complex. The first electronic excited state corresponds to the excess electron transfer from chlorine to acetonitrile fragment. This state is a precursor of the observed charge-transfer-to-solvent state. 相似文献
6.
A new straightforward method of synthesis of dendrimers, using two branched monomers (CA(2) and DB(2)), is described. Each generation is obtained in a single quantitative step, with only N(2) or H(2)O as byproducts; generation 4 is obtained in only four steps. The end groups are alternatively phosphines and hydrazines; their versatile reactivity is illustrated by the reaction of generation 4 with a branched CD(5) monomer, which increases the number of end groups in a single step from 48 to 250. 相似文献
7.
John D. Roehling Christopher W. Rochester Hyun Wook Ro Peng Wang Jaroslaw Majewski K. Joost Batenburg Ilke Arslan Dean M. Delongchamp Adam J. Moulé 《Journal of Polymer Science.Polymer Physics》2014,52(19):1291-1300
The morphology in mixed bulk‐heterojunction films are compared using three different quantitative measurement techniques. We compare the vertical composition changes using high‐angle annular dark‐field scanning transmission electron microscopy with electron tomography and neutron and x‐ray reflectometry. The three measurement techniques yield qualitatively comparable vertical concentration measurements. The presence of a metal cathode during thermal annealing is observed to alter the fullerene concentration throughout the thickness of the film for all measurements. However, the absolute vertical concentration of fullerene is quantitatively different for the three measurements. The origin of the quantitative measurement differences is discussed. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 1291–1300 相似文献
8.
Andrzej Okuniewski Jaroslaw Chojnacki Katarzyna Baranowska Barbara Becker 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(2):195-198
Two new dialkylammonium thiosulfates, namely bis(diisopropylammonium) thiosulfate, 2C6H16N+·S2O32−, (I), and bis(tert‐butylammonium) thiosulfate, 2C4H12N+·S2O32−, (II), have been characterized. The secondary ammonium salt (I) crystallizes with Z = 4, while the primary ammonium salt (II), with more hydrogen‐bond donors, crystallizes with Z = 8 and a noncrystallographic centre of inversion. In both salts, the organic cations and thiosulfate anions are linked within extensive N—H...O and N—H...S hydrogen‐bond networks, forming extended two‐dimensional layers. Layers are parallel to (10) in (I) and to (002) in (II), and have a polar interior and a nonpolar hydrocarbon exterior. The layered structure and hydrogen‐bond motifs observed in (I) and (II) are similar to those in related ammonium sulfates. 相似文献
9.
Two-component laminates made of conductors distributed non-periodically as laminas along one direction are considered in this note. The macroscopic properties of these laminates are described by continuous slowly-varying functions across laminas. In order to analyse heat conduction, the approach, called the tolerance modelling, is used. The aim of this note is to use averaged equations of the tolerance model for transversally graded laminates to analyse stationary heat conduction across laminas. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
10.
Significant progress has recently been made in de novo protein structure prediction. The Rosetta method by Baker and colleagues, which is based on the idea of assembling putative models from a library of k-mer fragments derived from known three-dimensional protein structures, proved to be particularly successful. Critical components of the Rosetta approach are various sequence-dependent as well as sequence-independent measures that are used to rank alternative models and to enhance sampling of native-like conformations. In the present work we revisit several sequence-independent filters that have been used to enhance the discrimination of native and native-like structures from misfolded structures, such as the overall compactness of the structure and its contact order. We also propose a novel sequence-independent filter, based on the shape of the mean inter-residue radial distribution function. Using the Rosetta, Park–Levitt and CASP4 sets of decoys it is shown that sequence-independent filters are in fact more successful in distinguishing native structures in Rosetta and CASP4 tests than commonly used knowledge-based pairwise potentials. The latter are typically designed to distinguish native structures in a population of well-folded alternatives, and they fail to discriminate between native-like and non-physically packed misfolded structures from Rosetta simulations. Moreover, a rigorous attempt to optimize pairwise potentials for recognition of homologous structures in threading by using a linear programming approach leads to further deterioration of performance in terms of recognition of native structures from the Rosetta set. These findings shed light onto the success of tailored scoring functions used in the Rosetta protocol and provide support for explicit inclusion of both sequence dependent and sequence independent measures in the design of scoring functions. A Web server that enables ranking of decoy structures according to sequence independent filters considered here is available at http://sift.chmcc.org. 相似文献