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Time-resolved measurements of the microwave field effect using optically detected EPR (ODEPR) have demonstrated that the amplitude and lifetime of the slow component of fluorescence are additionally reduced by an external microwave field, at a microwave frequency of 9400 MHz, a constant magnetic field of 0.3295 T and an oxalylfluoride pressure of 30 mTorr. This is accompanied by an increase in the fast component amplitude, at a constant decay rate of (2.36 x 0.19) 107 s-1. The fluorescence intensity was found to decrease, and phosphorescence intensity to increase, with subsequent saturation at higher microwave intensities. The experimental data are interpreted using the indirect mechanism theory in the limit of low-level density. [ABSTRACT FROM AUTHOR]

Fluorescence decay of gaseous oxalylfluoride (COF)[sub 2] excited to the A˜ [sup 1]A[sub u](7[sup 1]5[sup 1]) level was measured as a function of gas pressure in absence and in presence of magnetic field, B=0.3 T. On excitation to this level, the dynamics in both zero and nonzero fields may be described in the intermediate-molecule limit, with the fluorescence exhibiting biexponential and triexponential decay, respectively. The fast component decay rate constant k[sub f]=(5.31±0.22)·10[sup 7] s[sup -1] is independent on the (COF)[sub 2] gas pressure or magnetic field strength, while that of the first slow component depends on both. The second slow component lifetime is independent of the field strength, while dependent on the gas pressure. The Stern-Volmer dependence, measured with a field in the 0.3-12 mTorr pressure range, is nonlinear. The results obtained were explained by the indirect (electronic- and nuclear-spin-decoupling) mechanism, proposed earlier. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The intermediate LIF spectra were observed and compared in the NO[sub 2] (λ[sub exc]>400 nm) and ClONO[sub 2] (λ[sub exc]=308 nm) photolyses. Both spectra could be assigned to the same transient. Transient fluorescence spectra were recorded in the 12 500-16 400 cm-1 range at λ[sub exc]=436.45 nm. Analysis shows that the observed intermediate spectra can be attributed to the NO[sub 3] radical. The NO[sub 3] lifetime variations in the presence of CF[sub 4], CF[sub 3]Cl, CF[sub 2]Cl[sub 2], CFCl[sub 3], and CCl[sub 4] were also studied. It was shown that these compounds only influence the photolysis yield of NO[sub 3], without affecting its lifetime. The magnetic field influence on the discrete and total NO[sub 2] fluorescence, and on the NO[sub 3] radical yield were also measured using λ[sub exc]=436.45, 458.13, 478.93, and 489.12 nm. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A mathematical model has been constructed and verified for the behavior of a composite barrier under the conditions of shock-wave loading. An analytical-experimental method has been used to assess the effects of a modified composite barrier in high-velocity interaction with a spherical steel striker in the velocity range of 500–1200 m/s. [ABSTRACT FROM AUTHOR]

Consideration is given to conditions ensuring stable high-velocity motion of supercavitating kinetic strikers in water. To investigate the stressed-strained state and a possible destruction of solid bodies during the motion in water and in interaction with underwater barriers of various types, the authors carry out mathematical modeling based on a unified methodological approach of the continuum mechanics. The range of the velocities under study is 500-1590 m/s. Results of the group start of supercavitating strikers are given. [ABSTRACT FROM AUTHOR]

We consider the possibility of obtaining composites with increased mechanical strength resistant to high-velocity impact by means of self-propagating high-temperature synthesis (SHS) of metal-ceramic materials with graded composition-in particular, of layered type. A two-layer combined metal-ceramic material has been developed comprising NiTi-bonded titanium diboride (TiB2) layer on a metallic titanium substrate layer. The impact resistance of this composite is advantageous to that of a homogeneous titanium plate, which is manifested by the absence of a spall crater upon the impact of a spherical steel projectile and by stronger deformation and prefracture cracking of the projectile. [ABSTRACT FROM AUTHOR]

Water degassing and removal of salts by high-power acoustic pulses are analyzed. A model explaining the mechanisms of these processes is proposed. [ABSTRACT FROM AUTHOR]

Method of computer modeling of behavior of cylindrical and lamellar bones under the hypervelocity impact is suggested. This method allows in the frame of mechanics of continuous medium to calculate the stress strain behavior and damage in bone tissues under the shock wave impact. The processes of shock correlation of steel fragments of different shape with diaphysis of cylindrical bones and flat bone of calvaria under the impact 500 m/s are studied. The given method can be used for the evaluation of damage area of bone tissue of shock wave osteoporosis under the gunshot wound.

Specific features of the automated computerized diagnostic complex based on electrometric methods and used for the auricular diagnostics have been considered. A functional scheme of the complex is given. Biophysical aspects of measuring the skin conductivity in acupuncture zones of the auricle are discussed. Special attention is paid to the diagnostic algorithms and to the control for their efficiency.

The paper treats of the problems related to the design of the apparatus and programmed means of a set up for auricular diagnosis and therapy based on the experimental and reported data the authors substantiate the selection of the modes of the set up running in the course of search for active acupuncture areas, their diagnosis and therapy, describe technical decisions aimed at the enhancement of the ergonometric and technical characteristics of the set up. Provide a block diagram of the set up and algorithm maintaining its work in different modes.

The new approach to the construction of the problem-orientated automated working places of the main-modular structure, suggested by the authors, solves not only the concrete problems of the clinical subdivision in collecting, storing and processing information but can also be the basis of the information system of a health care facility as a whole (e.g. diagnostic centers of various purpose, specialized clinics and outpatient polyclinics).

The questions related to the design of the hardware and software means for the automation complex, which allows multiparameter analysis of the GSR signal based on IBM PC/XT microcomputer are being considered in the present article. The choice of the structure for the complex and working parameters of the separate modules is based on the experimental and printed data. Microcomputer GSR signal input and its further processing algorithms are presented. The possibility to simplify the soft- and hardware of the complex with the help of the rational choice of its structure and regarding the peculiarities of the GSR signal frequency-amplitude parameters is described.