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排序方式: 共有237条查询结果,搜索用时 250 毫秒
1.
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
2.
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
3.
Abramavicius D Nemeth A Milota F Sperling J Mukamel S Kauffmann HF 《Physical review letters》2012,108(6):067401
The two-exciton manifold of a double-wall cylindrical molecular aggregate is studied using a coherent third order optical technique. Experiments reveal the anharmonic character of the exciton bands. Atomistic simulations of the exciton-exciton scattering show that the excitons can be treated as weakly coupled hard-core bosons. The weak coupling stems from the extended exciton delocalization made possible by the nanotube geometry. 相似文献
4.
Clusters of temporal optical solitons--stable self-localized light pulses preserving their form during propagation--exhibit properties characteristic of that encountered in crystals. Here, we introduce the concept of temporal solitonic information crystals formed by the lattices of optical pulses with variable phases. The proposed general idea offers new approaches to optical coherent transmission technology and can be generalized to dispersion-managed and dissipative solitons as well as scaled to a variety of physical platforms from fiber optics to silicon chips. We discuss the key properties of such dynamic temporal crystals that mathematically correspond to non-hermitian lattices and examine the types of collective mode instabilities determining the lifetime of the soliton train. This transfer of techniques and concepts from solid state physics to information theory promises a new outlook on information storage and transmission. 相似文献
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7.
Warminski Jerzy Kloda Lukasz Latalski Jaroslaw Mitura Andrzej Kowalczuk Marcin 《Nonlinear dynamics》2021,105(4):3255-3270
Nonlinear Dynamics - This paper investigates the time-varying formation tracking (TVFT) problem of multiple heterogeneous Euler–Lagrange agents (MHELAs) with predefined-time convergence... 相似文献
8.
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
9.
Robert Musiol Barbara Podeszwa Jacek Finster Halina Niedbala Jaroslaw Polanski 《Monatshefte für Chemie / Chemical Monthly》2006,137(9):1211-1217
Summary. Aromatic aldehydes undergo condensation with quinaldines under microwave irradiation to afford structurally diverse styrylquinolines
in high yields under solvent-free conditions. A comparison with the conventional method clearly indicates the advantages of
the new protocol. 相似文献
10.
Sturm's chain technique for evaluation of a number of real roots of polynomials is applied to construct a simple algorithm for global optimization of polynomials or generally for rational functions of finite global minimal value. The method can be applied both to find the global minimum in an interval or without any constraints. It is shown how to use the method to minimize globally a truncated Fourier series. The results of numerical tests are presented and discussed. The cost of the method scales as the square of the degree of the polynomial. 相似文献