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排序方式: 共有635条查询结果,搜索用时 9 毫秒
101.
Konstantinos Spiliopoulos 《Journal of Theoretical Probability》2012,25(4):925-949
We study the large deviations principle for one-dimensional, continuous, homogeneous, strong Markov processes that do not necessarily behave locally as a Wiener process. Any strong Markov process X t in ? that is continuous with probability one, under some minimal regularity conditions, is governed by a generalized elliptic operator D v D u , where v and u are two strictly increasing functions, v is right-continuous and u is continuous. In this paper, we study large deviations principle for Markov processes whose infinitesimal generator is ??D v D u where 0<???1. This result generalizes the classical large deviations results for a large class of one-dimensional ??classical?? stochastic processes. Moreover, we consider reaction-diffusion equations governed by a generalized operator D v D u . We apply our results to the problem of wavefront propagation for these type of reaction-diffusion equations. 相似文献
102.
Orestis L. Katsamenis Vagelis Karoutsos Konstantinos Kontostanos Elias C. Panagiotopoulos Helen Papadaki Nikolaos Bouropoulos 《Crystal Research and Technology》2012,47(11):1201-1209
Meniscus is a fibrocartilaginous tissue composed mainly of water and a dense elaborate collagen network with a predominantly circumferential alignment. Crystal formation and accumulation on meniscal tissue is frequently observed especially in elderly. In this study, we used X‐ray diffraction (XRD), FTIR and FT‐Raman for the structural identification of the depositions and Optical microscopy, Scanning Electron microscopy (SEM/EDX) and Atomic Force microscopy (AFM), in order to investigate the structural relationship between the crystal deposits and the collagen fibers of human meniscal tissues. We are reporting on the formation of intercalary “colonies” of Calcium Pyrophosphate Dihydrate (CPPD) crystals with two distinct morphologies corresponding to the monoclinic and the triclinic phase, as well as the formation of micro‐aggregations composed of nano‐crystalline HAP aggregations which are developed along the longitudinal axis of collagen fibers without extensively disturbing the collagens arrangement. 相似文献
103.
Colodrero RM Olivera-Pastor P Losilla ER Hernández-Alonso D Aranda MA Leon-Reina L Rius J Demadis KD Moreau B Villemin D Palomino M Rey F Cabeza A 《Inorganic chemistry》2012,51(14):7689-7698
Multifunctional materials, especially those combining two or more properties of interest, are attracting immense attention due to their potential applications. MOFs, metal organic frameworks, can be regarded as multifunctional materials if they show another useful property in addition to the adsorption behavior. Here, we report a new multifunctional light hybrid, MgH(6)ODTMP·2H(2)O(DMF)(0.5) (1), which has been synthesized using the tetraphosphonic acid H(8)ODTMP, octamethylenediamine-N,N,N',N'-tetrakis(methylenephosphonic acid), by high-throughput methodology. Its crystal structure, solved by Patterson-function direct methods from synchrotron powder X-ray diffraction, was characterized by a 3D pillared open framework containing cross-linked 1D channels filled with water and DMF. Upon H(2)O and DMF removal and subsequent rehydration, MgH(6)ODTMP·2H(2)O (2) and MgH(6)ODTMP·6H(2)O (3) can be formed. These processes take place through crystalline-quasi-amorphous-crystalline transformations, during which the integrity of the framework is maintained. A water adsorption study, at constant temperature, showed that this magnesium tetraphosphonate hybrid reversibly equilibrates its lattice water content as a function of the water partial pressure. Combination of the structural study and gas adsorption characterization (N(2), CO(2), and CH(4)) indicates an ultramicroporous framework. High-pressure CO(2) adsorption data are also reported. Finally, impedance data indicates that 3 has high proton conductivity σ = 1.6 × 10(-3) S cm(-1) at T = 292 K at ~100% relative humidity with an activation energy of 0.31 eV. 相似文献
104.
The present work concerns with the investigation of the interior transmission problem, which is naturally associated to the
inverse elastic scattering problem of determining the support of an isotropic homogeneous penetrable body from a knowledge
of the time harmonic incident plane waves and the far-field patterns of the corresponding scattered wave-fields. Our approach
combines a boundary integral formulation of the problem and a compact perturbation argument to establish the discreteness
of the set of transmission eigenvalues and the well-posedness of the interior transmission problem under the most general
assumptions on the elastic parameters of the underlying media.
相似文献
105.
Kordatos Konstantinos Prato Maurizio Menna Enzo Scorrano Gianfranco Maggini Michele 《Journal of Sol-Gel Science and Technology》2001,22(3):237-244
We report on the synthesis of fullerene derivatives containing a trialkoxysilane moiety that exhibit enhanced solubility in solvents commonly used for sol-gel processing. These derivatives have been successfully embedded in glassy bulk samples and thin films that show very promising optical limiting properties. 相似文献
106.
Konstantinos G. Gatos Lszl Szzdi Bla Puknszky Jzsef Karger‐Kocsis 《Macromolecular rapid communications》2005,26(11):915-919
Summary: The effect of peroxide vulcanization on organoclay dispersion in hydrogenated nitrile rubber (HNBR)/organo‐montmorillonite (organo‐MMT) nanocomposites was investigated. Three types of organoclays were tested, one containing a primary amine and two bearing quaternary intercalants. In contrast to sulfur vulcanization, which in combination with primary amine intercalants produced a confined/deintercalated clay structure, the peroxide curing yielded well‐ordered intercalated nanocomposites. The tensile mechanical performance and oxygen permeability of the HNBR nanocomposites were determined.
107.
Maria Tsoukka Konstantinos E. Litinas Demetrios N. Nicolaides Dimitra J. Hadjipavlou‐Litina 《Journal of heterocyclic chemistry》2007,44(3):529-534
Furocoumarins 3,5 and pyranocoumarin 7 were synthesized from the reaction of furonaphthalenediones 2,4 and pyranonaphthalenedione 6 respectively with carbethoxymethylene(triphenyl)phosphorane in refluxing DCM for 3‐6 hours or under microwave irradiation in toluene for a few minutes. Compounds 3,5,7 and their precursors were tested as anti‐inflammatory/antioxidant agents. They were found to compete significantly high DMSO for OH radicals, to scavenge O2? and to inhibit lipoxygenase to a high extent. 相似文献
108.
Organic functionalization of carbon nanotubes 总被引:11,自引:0,他引:11
Georgakilas V Kordatos K Prato M Guldi DM Holzinger M Hirsch A 《Journal of the American Chemical Society》2002,124(5):760-761
A very general and versatile method for functionalizing different types of carbon nanotubes is described, using the 1,3-dipolar cycloaddition of azomethine ylides. Approximately one organic group per 100 carbon atoms of the nanotube is introduced, to yield remakably soluble bundles of nanotubes, as seen in transmission electron micrographs. The solubilization of the nanotubes generates a novel, interesting class of materials, which combines the properties of the nanotubes and the organic moiety, thus offering new opportunities for applications in materials science, including the preparation of nanocomposites. 相似文献
109.
Travelling‐wave ion mobility mass spectrometry and negative ion fragmentation of hybrid and complex N‐glycans 下载免费PDF全文
David J. Harvey Charlotte A. Scarff Matthew Edgeworth Kevin Pagel Konstantinos Thalassinos Weston B. Struwe Max Crispin James H. Scrivens 《Journal of mass spectrometry : JMS》2016,51(11):1064-1079
Nitrogen collisional cross sections (CCSs) of hybrid and complex glycans released from the glycoproteins IgG, gp120 (from human immunodeficiency virus), ovalbumin, α1‐acid glycoprotein and thyroglobulin were measured with a travelling‐wave ion mobility mass spectrometer using dextran as the calibrant. The utility of this instrument for isomer separation was also investigated. Some isomers, such as Man3GlcNAc3 from chicken ovalbumin and Man3GlcNAc3Fuc1 from thyroglobulin could be partially resolved and identified by their negative ion fragmentation spectra obtained by collision‐induced decomposition (CID). Several other larger glycans, however, although existing as isomers, produced only asymmetric rather than separated arrival time distributions (ATDs). Nevertheless, in these cases, isomers could often be detected by plotting extracted fragment ATDs of diagnostic fragment ions from the negative ion CID spectra obtained in the transfer cell of the Waters Synapt mass spectrometer. Coincidence in the drift times of all fragment ions with an asymmetric ATD profile in this work, and in the related earlier paper on high‐mannose glycans, usually suggested that separations were because of conformers or anomers, whereas symmetrical ATDs of fragments showing differences in drift times indicated isomer separation. Although some significant differences in CCSs were found for the smaller isomeric glycans, the differences found for the larger compounds were usually too small to be analytically useful. Possible correlations between CCSs and structural types were also investigated, and it was found that complex glycans tended to have slightly smaller CCSs than high‐mannose glycans of comparable molecular weight. In addition, biantennary glycans containing a core fucose and/or a bisecting GlcNAc residue fell on different mobility‐m/z trend lines to those glycans not so substituted with both of these substituents contributing to larger CCSs. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
110.
Konstantinos Fokianos Dag Tj?stheim 《Annals of the Institute of Statistical Mathematics》2012,64(6):1205-1225
We study statistical properties of a class of non-linear models for regression analysis of count time series. Under mild conditions, it is shown that a perturbed version of the model is geometrically ergodic and possesses moments of any order. This result turns out to be instrumental on deriving large sample properties of the maximum likelihood estimators of the regression parameters. The theory is illustrated with examples. 相似文献