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41.
Calculations for the relative width (Δω/ω0) as a function of refractive index and relative radius of the photonic band gap for the fcc closed packed 3-D dielectric microstructure are reported and comparison of experimental observations and theoretical predictions are given. This work is useful for the understanding of photonic crystals and occurrence of the photonic band gap.  相似文献   
42.
Ozonization of perfluoro-1-octene in Freon-113 yields the corresponding ozonide whose catalytic hydrogenation over Pd/C or hydride reduction leads to formation of perfluoroheptanoic acid; the reduction with lithium aluminum hydride gives 2,2,3,3,4,4,5,5,6,6,7,7,7-tridecafluoro-1-heptanol. Ozonization of perfluoro-1-octene in Freon-113 containing excess (3 equiv) alcohol affords the corresponding perfluoroheptanoic acid ester.  相似文献   
43.
Gas chromatography-mass spectrometry identified more than 20 volatile organic compounds isolated from leaves and flowers ofAegopodium podagrariaL.  相似文献   
44.
A specific, sensitive, rapid and reproducible method for the determination of flomoxef in human plasma using high‐performance liquid chromatography–tandem mass spectrometry was developed and validated. Flomoxef was detected using an electrospay ionization method operated in negative‐ion mode. Chromatographic separation was performed in gradient elution mode on a Luna® C18(2) column (3 μm , 20 × 4.0 mm) at a flow rate of 1 mL/min and runtime 3.5 min. The mobile phase consisted of acetonitrile and water containing 0.1% formic acid as additive. Extraction of flomoxef from plasma and precipitation of plasma proteins was performed with acetonitrile with an absolute recovery of 86.4 ± 1.6%. The calibration curve was linear with a correlation coefficient of 0.999 over the concentration range 10–5000 ng/mL and the lower limit of quantification was 10 ng/mL. The intra‐ and inter‐day precisions were <11.8%, while the accuracy ranged from 99.6 to 109.0%. A stability study of flomoxef revealed that it could be successfully analyzed at 4ºС over 24 h, but it was unstable in solutions at room temperature during short‐term storage (4 h) and several freeze–thaw cycles. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
45.
We consider several settings for C m -subharmonic extension and C m -harmonic approximation problems of Runge type in Euclidean domains.  相似文献   
46.
A method for estimating the model parameters is described, the results found in processing glass, flax, and carbon fiber and carbon bundle datasets are reported, and a comparison of different models is given. Translated from Mekhanika Kompozitnykh Materialov, Vol. 45, No. 1, pp. 65–74, January–February, 2008.  相似文献   
47.
Turbulent medium in problems of optical wave propagation through the atmosphere is usually nodeled as a set of statistically independent plane screens with a random two-dimensional field of phase progress. In this paper, we develop methods for the formation of nonperiodic phase screens infinitely extended in a certain direction, which are required in problems of dynamic simulation of wave propagation. __________ Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 1, pp. 21–34, January 2006.  相似文献   
48.
The possibility of using a unified mathematical model, based on the theory of Markov chains, to describe the distribution of the conditional fatigue limit at a fixed number of loading cycles and the residual strength of a specimen after cyclic loading is demonstrated. Numerical examples are presented. __________ Translated from Mekhanika Kompozitnykh Materialov, Vol. 44, No. 4, pp. 559–568, July–August, 2008.  相似文献   
49.
The reaction of (arylhydrazono)cyanothioacetamides with chloro ketones and phenacyl bromides was studied. The products are either thiazoles or 4,5-dihydrothiophenes, depending on the starting thioamides and halo ketones.  相似文献   
50.
The processes of ionization and energy transfer in a quantum system composed of two distant H atoms with an initial internuclear separation of 100 atomic units (5.29 nm) have been studied by the numerical solution of the time-dependent Schr?dinger equation beyond the Born-Oppenheimer approximation. Thereby it has been assumed that only one of the two H atoms was excited by temporally and spatially shaped laser pulses at various laser carrier frequencies. The quantum dynamics of the extended H-H system, which was taken to be initially either in an unentangled or an entangled ground state, has been explored within a linear three-dimensional model, including the two z coordinates of the electrons and the internuclear distance R. An efficient energy transfer from the laser-excited H atom (atom A) to the other H atom (atom B) and the ionization of the latter have been found. It has been shown that the physical mechanisms of the energy transfer as well as of the ionization of atom B are the Coulomb attraction of the laser driven electron of atom A by the proton of atom B and a short-range Coulomb repulsion of the two electrons when their wave functions strongly overlap in the domain of atom B.  相似文献   
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