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881.
Konstantin L. Kuzmin Ilya A. Timoshkin Evgeniya S. Zhukovskaya Yakov V. Lipatov Bogdan I. Lazoryak 《Composite Interfaces》2017,24(1):13-34
The present study explains the role of surface modification of constituent materials on composite material performance. The influence of silane and nano-hybrid coatings on mechanical properties of basalt fibers and composite materials on their base was investigated. Infrared spectroscopy indicated that modification of basalt fiber surface and nano-SiO2 was successfully applied. The surface modification leads to the significant increase in the tensile strength of basalt fibers compared to the non-coated fibers. The tensile strength of silane-treated fibers was established 23% higher than the non-coated fibers, indicating that silane plays a critical role in the strength retention of basalt fibers. Also it was pointed out that silane coupling agents can be used for the preparation of the nano-hybrid coating. Addition of SiO2 nanoparticles into the fiber surface was incorporated to enhance the interfacial bonding of basalt fiber reinforced epoxy composite. 相似文献
882.
A propagation of dipolar radiation in a finite length linear chain of identical dielectric spheres is investigated using the multisphere Mie scattering formalism (MSMS). A frequency pass band is shown to be formed near every Mie resonances inherent in the spheres. The manifestation of the pass band depends on the polarization of the travelling radiation. To prove this effect, a point dipole placed by the end of the chain is used as an external source of radiation. It is found that, if this dipole is directed parallel to the chain axis, the frequency pass bands exist if the refractive index of dielectric spheres is sufficiently large nr>1.9. For the dipole normal to the chain axis, the pass band can always be formed if the chain is sufficiently long. Such a distinction is due to different behavior of the far-field dipolar interaction between the spheres induced by the external source. The edges of the pass bands are defined by the guiding wave criterion based on the light-cone constraint. The criterion of creation of the pass bands correlate with condition of formation of high quality factor modes in these systems found in our previous papers. A comparison with the results available for infinite chains is made. In particular, we clarify the nature of braking down the band structure for small enough wavevectors. 相似文献
883.
Ilya Sh. Steinberg Vladimir A. Loskutov Yuri A. Shepetkin 《Optics Communications》2008,281(17):4297-4301
We have demonstrated two-photon induced recording of the microholograms at an arbitrary point within thick (∼100 μm) photopolymer material using photoinitiators on a basis of new cationic thioxanthone derivatives. Such material provides high values of refractive index change Δn = 4.8 × 10−3, and holographic recording sensitivity S = 1.2 cm/J. A nanosecond laser pulse at a wavelength of 532 nm was used for recording. For the selective on the depth reading of the microholograms the method of collinear heterodyning was applied. 相似文献
884.
Nykter M Price ND Larjo A Aho T Kauffman SA Yli-Harja O Shmulevich I 《Physical review letters》2008,100(5):058702
Network structure strongly constrains the range of dynamic behaviors available to a complex system. These system dynamics can be classified based on their response to perturbations over time into two distinct regimes, ordered or chaotic, separated by a critical phase transition. Numerous studies have shown that the most complex dynamics arise near the critical regime. Here we use an information theoretic approach to study structure-dynamics relationships within a unified framework and show that these relationships are most diverse in the critical regime. 相似文献
885.
Normal incidence of a plane electromagnetic wave on a periodical structure can be simulated by the finite-difference time-domain method using a single unit cell with periodical boundary conditions imposed on its borders. For the oblique wave incidence, the boundary conditions would contain time delays and thus are difficult to implement in the time-domain method. We propose a method of oblique incidence simulation, based on an iterative algorithm. The accuracy of this method is demonstrated by comparing it with the layer Korringa-Kohn-Rostoker frequency-domain method for calculation of transmission spectra of a monolayered photonic crystal. 相似文献
886.
Robert Pollice Felix Fleckenstein Ilya Shenderovich Peter Chen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(40):14419-14426
The importance of London dispersion for structure and stability of molecules with less than about 200 atoms has been established in recent years but the quantitative understanding is still largely based on computations because of a persistent lack of suitable experimental data. We herein report a comprehensive computational and experimental study of the compensation of London dispersion in proton‐bound dimer dissociations showing that total compensation is largely invariant in both polar and nonpolar aprotic solvents spanning a wide range of bulk polarizabilities. Additionally, we find that compensation by solvent (which is about 40–80 %) largely dominates over compensation in the gas phase (which is about 0–40 %) for typical experimental temperatures. 相似文献
887.
Konstantin A. Rufanov Ilya Yu. Titov Alex R. Petrov Klaus Harms Jrg Sundermeyer 《无机化学与普通化学杂志》2019,645(6-7):559-563
The Staudinger reaction of organic azides tBuN3, 1‐Ad‐N3, and DippN3 (Dipp = 2,6‐diisopropylphenyl) with (R)‐N,N′‐bis(diphenylphosphanyl)‐2,2′‐diamino‐1,1′‐binaphthyl [(R)‐Binam‐P], obtained by an optimized procedure from (R)‐(+)‐Binam, Ph2PCl, and Et3N in DCM, leads to preparation of a series of new C2‐symmetric bis‐iminophosphonamide ligands [(R)‐Binam(Ph2PN(H)R)2] [R = tBu ( 1 ), Ad ( 2 ), and Dipp ( 3 )]. The molecular structure of 1· 2DMSO was confirmed by X‐ray structure analysis. 相似文献
888.
Chemistry of Heterocyclic Compounds - Microreview summarizes the latest examples on NH-unsubstituted 1,2,3-triazole synthesis. The described methods are categorized according to the used starting... 相似文献
889.
890.
Lavastre O Illitchev I Jegou G Dixneuf PH 《Journal of the American Chemical Society》2002,124(19):5278-5279
A combinatorial approach was developed for the synthesis and the screening of a large variety of conjugated polymers. The parallel synthesis of 96 polyaryleneethynylene derivatives was performed on a 12 x 8 format from diethynyl and dibromoaryl building blocks, via a palladium-catalyzed carbon-carbon coupling reaction. The qualitative distinction between fluorescent and nonfluorescent polymers as well as between the different emission colors were obtained from a simple visual test or via a 96-well plate reader spectrofluorimeter. New solid-state blue-emitting polymers were detected. 相似文献