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161.
JPC – Journal of Planar Chromatography – Modern TLC - LogP values of 41 biologically active chalcones (Figure 1, 1) and their cyclic analogs, E-2-(X-benzylidene)-1-indanones (Figure 1,... 相似文献
162.
This article investigates the valuation of currency options when the dynamic of the spot Foreign Exchange (FX) rate is governed by a two-factor Markov-modulated stochastic volatility model, with the first stochastic volatility component driven by a lognormal diffusion process and the second independent stochastic volatility component driven by a continuous-time finite-state Markov chain model. The states of the Markov chain can be interpreted as the states of an economy. We employ the regime-switching Esscher transform to determine a martingale pricing measure for valuing currency options under the incomplete market setting. We consider the valuation of the European-style and American-style currency options. In the case of American options, we provide a decomposition result for the American option price into the sum of its European counterpart and the early exercise premium. Numerical results are included. 相似文献
163.
S. Takács 《Czechoslovak Journal of Physics》1990,40(9):1040-1053
The field distribution for superconducting cylinders and slabs with field dependent critical current densities in combined DC and AC magnetic fields and the corresponding magnetic fluxes are calculated. It is shown that all features of experimental magnetic-field profile measurements can be explained in the framework of field dependent critical current density. Even the quantitative agreement between the experimental and theoretical results using Kim's model is very good.I would like to acknowledge many stimulating discussions with Dr. F. Gömöry. 相似文献
164.
Terephthaldialdimine 1a reacted with alkenes to give 2,6-dialkylated products selectively in moderate to high isolated yields. In the case of terephthaldialdimine 1b having a substituent at site 2 in the phenyl ring, the alkylation takes place selectively at site 6 in the phenyl ring. In this alkylation, a meta-substituent affected the reactivity significantly because of the steric hindrance. 相似文献
165.
Analytical characteristics of DESI are summarized. Examples of applications to small and large molecules, to in situ analysis, and to high-throughput analyses are presented. Evidence is provided for both a heterogeneous charge-transfer mechanism and a droplet pick-up mechanism of ionization. The speed, lack of the need for sample preparation, selectivity, and sensitivity of DESI are all demonstrated and discussed. Instrumentation is also discussed. Forensic applications as well as emerging areas of application including tissue imaging are given emphasis. 相似文献
166.
Using liposome to shield an enzyme from hostile chemical environments during the sol-gel formation process has resulted in a novel approach to synthesizing silica sol-gel biocomposite materials. By reporting the encapsulation of horseradish peroxidase and firefly luciferase, we demonstrate that this new protocol can produce silica biocomposites that are more active than trapping the enzymes directly into hydrogels. 相似文献
167.
I. Fisch I. Olácsi J. Takács J. Vōrös 《Journal of Analytical and Applied Pyrolysis》1980,1(4):275-295
For the identification of isoprenoid-type compounds and other degradation products derived from the pyrolysis of phytol and plant pigments, a calculation method was developed to the evaluate the chromatograms, determining the retention indices or net retention volumes of different compounds. Calculations were made by means of computer for different stationary phases and temperatures. Gas chromatographic and derivatographic measurements were made with natural plant pigments and phytol, including the thermal degradation of the compounds mentioned above. Close agreement was found between the measured and calculated data and with literature data. 相似文献
168.
The effects of the magnetic field, Mach number and the permeability parameter on the wall jet flow (radial or plane) of an electrically conducting gas spreading over a permeable surface have been investigated. Taking the Prandtl number of the fluid as unity and assuming a linear relationship between viscosity and temperature, it is found that similar solutions for the velocity distribution exist for a specified distribution of the normal velocity along the wall and the corresponding distribution of the transverse magnetic field. Previous non-magnetic flow results have been improved by adopting a new and simple transformation of variables. 相似文献
169.
L. Takács 《Solid State Communications》1977,21(6):611-613
The magnetic anisotropy of a Fe80B20 (METGLAS 2605) metallic glass has been investigated by Mössbauer spectroscopy. The direction of magnetization is shown to be strongly temperature dependent with an unusually large out-of-plane component. The similarities between the electronic structure of this glassy alloy and the Fe2B and FeB intermetallic compounds are discussed briefly. 相似文献
170.