Behavior of Metal Particles Formed in Electric-Spark Dispersion of Aluminum in Aqueous Solutions

The effect of additives introduced into the working solution on the behavior of dispersed aluminumparticles obtained in electric erosion was studied.     

Detection of high-resolution Raman spectra in short oligonucleotides

High-resolution spectra of single-chain short oligonucleotides d(20G, 20T), where d is a deoxyribonucleoside, G is guanine, and T is thymine, have been obtained by the highly sensitive nonresonant Raman scattering method of biomacromolecules. In addition to their own multifunctional significance, short oligonucleotides attract interest as ideal model objects for revealing poorly studied peculiarities of tertiary and quaternary structures of DNA. The detection of narrow spectral lines has allowed determining the characteristic time scale and makes it possible to study the dynamics of fast relaxation processes of vibrational motions of atoms in biomacromolecules. It has been found that the FWHM of the narrowest 1355.4 cm^?1 spectral line attributed to the vibrations of the dT methyl group is 14.6 cm^?1. The corresponding lifetime is 0.38 ps.     

Selective resonance enhancement of Raman scattering intensity in photoinduced nonradiative charge transfer

This paper reports on the formation of complexes consisting of isolated free-standing crystalline semiconductor quantum dots, for example, nc-Si/SiO₂, functionalized by short oligonucleotides, for example, the single-stranded system d(20G, 20T). Here, d are deoxyribonucleotides, G and T are guanine and thymine nucleotides, respectively. It has been found that these complexes are unique objects for the elucidation of the specific features in the manifestation of new quantum-size effects in biomacromolecules. It has been demonstrated that the possibility exists of detecting and recording, in such complexes of biomacromolecules, spectrally selective resonance enhancement of Raman scattering intensity in fluctuations of nucleotide molecules due to coherent nonradiative transfer of a photoexcited electron and a hole at the interface of the complex. This dynamic optical imaging of spectral responses can be of applied interest for the development of nanobiophotonic technologies.     

Investigation of the molecular dynamics of some phenols and their acetyl isomers in solutions by NMR relaxation

The dynamics of relaxations and Fries rearrangements in phenol acetates and their acetyl isomers was studied by the NMR relaxation technique in acetone-d ₆. The results of ¹³C and ¹H spin-lattice nuclear relaxation measurements show that these experiments can be used for determining the mobility and activation energies of the molecular motions of compounds in different systems.     

Progressive Type II censored order statistics for multivariate observations

For a sequence of independent and identically distributed random vectors , i=1,2,…,n, we consider the conditional ordering of these random vectors with respect to the magnitudes of , where N is a p-variate continuous function defined on the support set of X₁ and satisfying certain regularity conditions. We also consider the Progressive Type II right censoring for multivariate observations using conditional ordering. The need for the conditional ordering of random vectors exists for example, in reliability analysis when a system has n independent components each consisting of p arbitrarily dependent and parallel connected elements. Let the vector of life lengths for the ith component of the system be , where denotes the life length of the jth element of the ith component. Then the first failure in the system occurs at time , and for this case . In this paper we introduce the conditionally ordered and Progressive Type II right-censored conditionally ordered statistics for multivariate observations and to study their distributional properties.     

Photoelectric properties of In/CdP2 surface barrier structures

We used vapor-phase crystallization to grow homogeneous single crystals of the compound CdP₂ of diameter 20 mm and length up to 50 mm. We determined the unit cell parameters and the composition of the single crystals grown. We created photosensitive In/CdP₂ surface barrier structures and studied their photosensitivity spectra. Based on these studies, we established the broadband character of the photosensitivity of the structures, the nature of the photoconversion processes, and the type of interband transitions. We conclude that it is possible to use CdP2 single crystals as broadband photoconverters for natural light.     

Properties of eigenvalues and spectral singularities for impulsive quadratic pencil of difference operators

In this paper, we investigate the spectral analysis of impulsive quadratic pencil of difference operators. We first present a boundary value problem consisting one interior impulsive point on the whole axis corresponding to the above mentioned operator. After introducing the solutions of impulsive quadratic pencil of difference equation, we obtain the asymptotic equation of the function related to the Wronskian of these solutions to be helpful for further works, then we determine resolvent operator and continuous spectrum. Finally, we provide sufficient conditions guarenteeing finiteness of eigenvalues and spectral singularities by means of uniqueness theorems of analytic functions. The main aim of this paper is demonstrating the impulsive quadratic pencil of difference operator is of finite number of eigenvalues and spectral singularities with finite multiplicities which is an uninvestigated problem proposed in the literature.     

Resonant Mandelstam-Brillouin light scattering and Raman scattering in semiconductors with intermediate exciton states belonging to discrete exciton bands and the continuous spectrum

The results of a theoretical and experimental investigation of resonant Mandelstam-Brillouin light scattering by thermal acoustic phonons with k=0 near the direct absorption edge (in the case of ZnSe crystals) are analyzed. The appearance of a new type of resonant increase in the intensity of Raman scattering by optical phonons with k≠0, which corresponds to resonance with the scattered light in the output channel, near the indirect absorption edge (in the case of semi-insulating GaP:N crystals) is also reported. The resonant gain reaches ∼4×10³ at frequencies corresponding to overtone scattering assisted by LO(X) and LO(L) phonons. Exciton states belonging to both discrete exciton bands and to the continuous spectrum are considered as the intermediate states involved in the scattering processes in calculations of the resonant scattering tensors. In addition, all the intraband transitions, as well as the interband transitions between the conduction band, the valence bands, and the spin-orbit split-off band are taken into account, and good agreement with the experimental results is obtained. Fiz. Tverd. Tela (St. Petersburg) 40, 938–940 (May 1998)     

Invariant confidence intervals for the main mass of values from the distribution in a population

We introduce the notion of invariant confidence interval containing the main mass of values for some class of populations, which is independent of the distribution of the population from the given class. It is shown that an invariant one-tail confidence interval for the class of populations with continuous distributions is generated by some order statistic.Translated from Vychislitel'naya i Prikladnaya Matematika, No. 65, pp. 112–117, 1988.