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A TKPF269 rotating mirror digital streak camera with a photosensitive element based on a CMOS array was developed for the purpose of replacing film in high-speed streak cameras (SFR-2M, USF-2, etc.). A brief description of the TKPF269 streak camera design is given. The space-time picture of the emergence of light from the ends of optical fibers upon firing of an explosive in a model assembly was simultaneously recorded by a TKPF269 streak camera and an USF-2 streak camera to compare the metrological characteristics of these devices. The results of experimental data processing are presented.

Purpose. The aim of this study was to evaluate the microcirculation in patients with acute coronary syndrome over the course of the disease. Design/methodology/approach. 48 patients were examined with average age of 65.3±5.1 years. The patients were delivered in an intensive care unit with a diagnosis of acute coronary syndrome. Analysis of clinical, instrumental and laboratory parameters was made depending on the final diagnosis: «myocardial infarction» - 26 patients, «unstable angina» - 22 patients. In addition, both linear and volume blood flow were evaluated on the distal phalanx of second finger of the right hand in all patients using the method of high-frequency (25 MHz) ultrasound Doppler study. Findings. At admission, in patients with acute myocardial infarction the linear velocity of blood flow was 10.27±1.18 mm/s, the volume rate of flow 4.67±0.55 ml/min; in the subgroup of patients with unstable angina these figures were 14.09±1.50 mm/s and 6.64±0.71 ml/min, respectively (p

The experimental results on the initiation of various (γ, n) and (p, n) nuclear reactions in the picosecond laser plasma are presented. It is demonstrated that the following (γ, n) and (p, n) nuclear reactions can be initiated at a laser intensity of 2 × 1018 W/cm2 with the threshold energies of γ-quanta ranging from 1.67 to 7.56 MeV and the threshold energies of protons ranging from 1.88 to 5 MeV: 9Be(γ, n)2α, 181Ta(γ, n)180Ta, 7Li(p, n)7Be, 63Cu(p, n)63Zn, 48Ti(p, n)48V. The method based on the detection of fast neutrons using the 3He counters is employed for the measurement of the number of the initiated (γ, n) and (p, n) nuclear reactions. The measured yield of the (γ, n) and (p, n) nuclear reactions ranges from 5 × 101 to 105 reactions per laser pulse.

Results of experimental investigations of fast-proton production in a laser plasma are presented for the case where the intensity of laser radiation at the targets is 2 × 1018 W/cm2. Three processes of fast-proton acceleration in laser plasma are investigated: (1) the acceleration of protons from the front surface toward the laser pulse, (ii) the acceleration of protons from the front surface of the target toward its interior, and (iii) the acceleration of protons from the rear foil surface in the outward direction. The activation procedure and CR-39 tracker detectors featuring a set of various-thickness aluminum filters were used to record fast protons. It turned out that the proton-acceleration process is the most efficient in the case of proton acceleration from the rear foil surface in the outward direction. Experimental results revealed that about N p = 107 protons of energy in the region E p > 1.9 MeV that are accelerated from the target surface toward a laser ray, N p = 4× 107 protons of energy in the region E p > 1.9 MeV that are accelerated fromthe front surface of the target toward its interior, and N p = 4×108 protons of energy in the region E p > 1.9 MeV that are accelerated from the rear foil surface in the outward direction are generated at a laser-radiation intensity of 2 × 1018 W/cm2 at the surface of aluminum, copper, and titanium targets. Experimental investigations aimed at optimizing the process of proton acceleration from the rear surface of aluminum foils were performed by varying the foil thickness over the range between 1 and 100 µm. The results of these experiments showed that there is an optimum foil thickness of 10 µm, in which case protons of maximum energy 5 MeV are generated.

The results of experiments devoted to studying the excitation of the promising nuclear fusion reactions 6Li(d, α)4He, 3He(d, p)4He, 11B(p, 3α), and 7Li(p, α)4He, along with the standard reaction D(d, n)3He, in picosecond laser plasmas are presented. For the first time, it was shown that these reactions may proceed at a moderate laser-radiation intensity of 2 × 1018 W/cm2, the respective yield being 2 × 103 to 105 per laser pulse. A brief survey of the main processes responsible for the generation of fast electrons and fast ions (protons) at the front surface of the target and for the excitation of nuclear fusion reactions is given. The calculated and experimental results on the yield from nuclear fusion reactions in picosecond laser plasmas are compared. The possibilities for optimizing the yield from the promising fusion reactions excited in femto- and picosecond laser plasmas are discussed.

The results of experiments devoted to studying the generation of MeV photons and protons in picosecond laser plasmas at a laser beam intensity of 1018 W/cm2 on Be, Ta, LiF and H7Li targets are presented. Nuclear reactions (γ, n) and (p, n) were used to detect MeV photons and protons. The number of MeV photons and protons generated in laser plasmas was found from the measured neutron yield. Possibilities of particle acceleration due to the formation of pinch structures in laser plasmas are discussed. Calculated and experimental results are compared.

Experimental results on the effect of picosecond and nanosecond prepulses on the neutron yield in laser picosecond plasma on the surface of solid (CD2)n targets at a laser intensity of 1018 W/cm2 are presented. It is demonstrated that the picosecond (nanosecond) prepulse decreases the neutron yield at a laser prepulse intensity of higher than 1013 (1012) W/cm2. The estimates indicate three possible mechanisms for the realization of the observed effect: stimulated Mandelstam-Brillouin scattering of the main pulse by the preplasma, channels of the generation of fast ions, and their possible deceleration in the preplasma. The results of calculations are compared with the experimental data.

Experimental data on neutron production in a plasma generated on a Be target by a picosecond laser of intensity 2 x 10{sup 18} W/cm{sup 2} are presented. In contrast to previous measurements, a Ta converter is not used in this study to generate {gamma} rays. The neutron yield is equal to 2 x 10{sup 3} over a solid angle of 4{pi} steradians per laser pulse. A simultaneous measurement of the maximum energy of hard x rays gave E{sub {gamma}}{sub max} {approx} 6 MeV, the number of these photons being 5 x 10{sup 8} over an angle of 4{pi} steradians per laser pulse. The energy distributions of fast electrons and photons are estimated theoretically.

Experimental data are reported on the generation of fast ions in a picosecond laser plasma at a laser-radiation intensity of 2 × 1018 W/cm2. The results are obtained by measuring the Doppler spectra of hydrogen-like fluorine ions. An important feature of the energy distribution of fast ions is a slow decrease up to an energy of 1.4 MeV. In addition, the directional motion of fast ions deep into a target is found due to the redshift of the Doppler profile of the Ly α line. The parameters of the energy distribution of the ions are theoretically estimated.

Neutron production as a result of the reaction 2H(d, n)3He in a picosecond laser plasma is reported. A considerable neutron yield of 5×104 per pulse is obtained for the first time in a picosecond laser plasma on the surface of a solid deuterated target at laser radiation intensity of 3×1017 W/cm2.

The proton and deuteron yields from thin targets irradiated by a picosecond laser pulse with an average radiation intensity of ≤4×1018 W/cm2 at the target were measured in the megaelectron-volt energy range. A ring structure was observed for the outgoing ions, and the angular ion-beam divergence was found to be extremely small (0.5°). The fast-ion generation mechanism allowing for the appearance of ring structure is discussed, and the characteristic energies and spatioangular ion-beam distribution are estimated.

A high-sensitivity gas analyzer was developed to measure the concentration of individual gases in multicomponent gas mixtures. The gas analyzer consists of the following main elements: a waveguide CO2 laser, a resonance optoacoustical cell, and a computer. The database of the computer contains information about absorption lines of 37 gases. The thresholds of the detection of individual gases by the gas analyzer are given. The ammonia detection threshold and error are 0.015 ppb and 15%, respectively.

Interferometric system for detecting radiation wavelength shift functions based on a Fabry-Perot interferometer. Means developed for enhancing the system performance are described, namely: a method of increasing illumination of detected fringes for enhancing the system sensitivity, and a method of compensating interference maxima spreading caused by misalignment of mirrors that allows enhancing accuracy of light frequency shift measurement. The way to increase detected fringe brightness is based on additional reduction of the divergence of passing through the interferometer light beam. This method allows compensating negative effect of collimating lens spherical aberrations, and, using them, increasing the detector illumination. The way of compensating the interferometer mirrors misalignment effect on the detected fringe is based on use of specific relative position of beams from various parts of the interferometer near the focal plane of the focusing lens.

A mathematical model of the heat and mass transfer in a multicomponent vapor-gas phase is developed for the case of ideal mixing of components with a decrease in the total pressure of the medium above the surface of a wet material or solution.

Experimental studies are presented on composition, density and structure influence onto the neutron yield resulting from deuterium-containing target interaction with laser light of 10 18 W/cm 2 . Experimental data are compared with theoretical and simulation results.

Experimental studies are presented on composition, density and structure influence onto the neutron yield resulting from deuterium‐containing target interaction with laser light of 1018 W/cm2. Experimental data is compared with theoretical and simulation results.

The yield of $\ensuremath{\alpha}$ particles in neutronless fusion reactions $^{11}\mathrm{B}+p$ in plasmas produced by picosecond laser pulses with the peak intensity of $2\ifmmode\times\else\texttimes\fi{}{10}^{18}\phantom{\rule{0.3em}{0ex}}\mathrm{W}∕{\mathrm{cm}}^{2}$ has been observed. Experiments were carried out on the ``Neodymium'' laser facility at the pulse energy of $10--12\phantom{\rule{0.3em}{0ex}}\mathrm{J}$ and pulse duration of $1.5\phantom{\rule{0.3em}{0ex}}\mathrm{ps}$. The composite targets $^{11}\mathrm{B}+{(\mathrm{C}{\mathrm{H}}_{2})}_{n}$ were used. The yield of ${10}^{3}$ $\ensuremath{\alpha}$ particles per pulse has been observed. The energy spectrum of $\ensuremath{\alpha}$ particles contains two maxima: at $3--4\phantom{\rule{0.3em}{0ex}}\mathrm{MeV}$ and at $6--10\phantom{\rule{0.3em}{0ex}}\mathrm{MeV}$. The first of these peaks corresponds to the secondary ${\ensuremath{\alpha}}_{12}$ particles at the decay of the intermediate first excited state of $^{8}\mathrm{Be}$, whereas the second peak demonstrates generation of ${\ensuremath{\alpha}}_{1}$ particles in the reaction $^{11}\mathrm{B}+p$ with the production of this excited state. Simultaneous measurements of neutrons result in zero yield, which proves the observation of neutronless fusion reactions in our experiments.

Results of fast light ion yield measurements are presented. Laser-plasma experiments were carried out on picosecond laser PROGRESS-P at laser intensities on a target to be 1 ÷ 4•1018 W/cm2. Ring image and extremely small angular divergence of fast ion beam were found. Hard ions with energy more than 8 MeV were recorded. Model of fast ion generation is discussed and typical energy and spatial distribution of fast ion extension are estimated.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

To compare efficacy of conventional therapy, antihypoxants olifen and amthizol (groups 1, 2 and 3, respectively) 49 patients with congestive heart failure stage IIb according to the Vasilenko-Strazhesko classification were treated. In hospital the pre-hospital scheme of treatment was not changed except the following positions: group 1 patients received strophanthin instead of oral digoxin, group 2 and 3 patients received adjuvant olifen and amthizol, respectively. Stabilization of the condition occurred in 10 days, on the average, in each group. In the 1st group good results were obtained due to stroke volume increase, in the 2nd and 3d due to the ability of olifen and amthizol to prevent tissue hypoxia.

The computer controlled multistage synthesis of fine-grained photographic emulsions is described. Scanning electron microscopy was used to investigate the shape and size (10 – 1500 nm) distribution of silver halide crystals in the emulsion. The influence of stirrers in the chemical reactor and also surfactant addition on the emulsion quality was revealed. In the result of the investigation a new method for obtaining of high quality photosensitive materials based on the tabular multicoated silver halide crystals was proposed.

The article examines nonsteady heat and mass transfer in the process of drying by reduced pressure, on the assumption that the moisture is situated on the surface of an infinite plate.

The authors studied the potentialities of employment of a new method of exercise tests (cyclic bicycle ergometry) for the assessment of convalescents' function and working capacity following acute communicable diseases. The above method showed the relationship of convalescents' function and working capacity with a nosological form and stage of convalescence. It was established that some indices of patients' function did not return to normal by discharge. Different mechanisms were shown to lie in the basis of disturbances in various infections. A conclusion was made that convalescents were in need of differentiated pathogenetically founded and purpose-oriented recovery therapeutic measures which should be taken into account in drawing up programs for their rehabilitation and follow-up after acute communicable diseases.

The investigation of the peripheral circulation by using the all-purpose occlusion rheoplethysmography enables the reaction of rising the venous tone in response to the action exerted by the tissue ischemia products to be quantitatively estimated along with a one-time determination of the arterial and venous hemodynamics of the crus at rest and in reactive hyperemia. The blood flow volume-velocity rates determined by means of the proposed method are of a considerable diagnostic value for characterization of the peripheral hemodynamics in patients with cardio-vascular pathology, in performing pharmacological tests and in medication with drugs displaying vasoactive properties.