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101.
Spectra of the photoelectromotive force of p-CuInSe2 single crystals obtained by directional crystallization of a stoichiometric-composition melt in an upright ampoule have been investigated by the method of phase-sensitive detection. A difference in the phase shifts between the exciting light and the arising photoelectromotive force in the extrinsic (impurity) and intrinsic regions of optical absorption is determined. The lifetime in the region of optical self-absorption is found to equal τ=15·10−6 at T=77 K. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 129–131, January–February, 1997.  相似文献   
102.
The fluorescence properties of protopine and allocryptopine in aqueous and organic environments are described for the first time. The fluorescence of alkaloids and their pH-dependent interconversion to cationic forms (transannular interaction) were studied using steady-state and time-resolved fluorescence techniques. For the analysis of tricyclic base and cis/trans tetracyclic cations of the alkaloids, NMR and X-ray crystallography were used.  相似文献   
103.
The radiative decayη′→π + π ? γ has been studied with the statistics of ?2000 events. Different ways of describingm ππ distribution are considered. It is shown that if the dominating contribution to this process is made by the decay channel η′→ργ, then the generally accepted ways of describing the ρ peak do not agree with experimental data.  相似文献   
104.
Different approaches to statistical sensitivity analysis for optimal solutions of stochastic programs are discussed and compared. Possibilities of drawing conclusions about asymptotic behavior of estimated optimal solutions by means of stability properties of auxiliary randomly perturbed convex quadratic programs are indicated and illustrated on a numerical example.  相似文献   
105.
The contamination technique is presented as a flexible and relatively easily tractable tool to postoptimality analysis for scenario based multistage stochastic linear programs. It is promising especially in cases when the influence of additional or out-of-sample scenarios on the already solved problem is to be explored.Research supported in part by the Grant Agency of the Czech Republic under Grant No. 402/93/0631.  相似文献   
106.
107.
New methods of flow injection analysis (FIA) neutralization titrations of phenothiazine derivatives in aqueous micellar medium of a cationic surfactant using potentiometric and spectrophotometric detection were proposed; titrations with a mixing gradient chamber and high-speed titrations were compared. The FIA titration method in non-aqueous media based on an official method of determination (titration with perchloric acid in anhydrous acetic acid) was also developed. Under optimized reaction conditions and flow-through parameters, the calibration range and equations, the sensitivity, and the repeatability of all methods were found and discussed. All titrations were assayed for medicinal forms.  相似文献   
108.
The behaviour of six substituted aminomethylphenol dyes, having pI values between 5.3 and 10.4, in capillary isoelectric focusing with electroosmotic zone displacement is described. Using untreated fused-silica capillaries and different neutral capillary conditioners in the catholyte, the low-molecular-mass dyes are shown to focus and elute reproducibly in the order of decreasing pI values. In the absence of proteins, the detection times of the dyes are independent of the sampled amount. Hence these substances permit the characterization of the pH gradient produced in this capillary isoelectric focusing method. With concurrent focusing of dyes and test proteins, a macromolecular impact on detection times (reduction of electroosmosis)‘ is revealed. The effect is shown to be dependent on the type and amount of proteins applied and has been observed with three different capillary conditioners. Nevertheless, mapping of the pH gradient with these dyes and determining the pI values of known proteins is shown to provide values in agreement with those in the literature. Hence the substituted aminomethylphenol dyes can be employed as pI markers in capillary isoelectric focusing with electroosmotic zone displacement. Further, focusing and separation of two of the six dyes by preparative recycling free fluid isoelectric focusing is described, illustrating that the substituted aminomethylphenol dyes are also applicable to other free fluid focusing methods.  相似文献   
109.
The boron trifluoride diethyl etherate catalyzed intramolecular cyclization of diethyl 2-(dialkoxyphosphorylethynyl)-2-arylaminomalonates afforded a series of novel 3-phosphonylated indoles, diethyl 2-[3-(dialkoxyphosphoryl)-1H-indol-2-yl]propanedioates. Decarboxylation of the latter compounds resulted in the formation of ethyl 2-[3-(dialkoxyphosphoryl)-1H-indol-2-yl]acetates.  相似文献   
110.
JETP Letters - The first data on the yield of the lightest nuclear fragments (protons p, deuterons d, and tritons t) with high transverse momenta pT at an angle of 40° in the laboratory...  相似文献   
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