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The review covers aspects connected with formation of concept of pharmaceutic aid in occupational diseases. The authors emphasize problems of interactions between pharmacy workers and medical organizations officers for optimizing pharmaceutic aid. Prospects of the pharmaceutic aid concept implementation into treatment of specific diseases including occupational diseases in miners are shown.

The MuCap experiment at the Paul Scherrer Institute performed a high-precision measurement of the rate of the basic electroweak process of nuclear muon capture by the proton, $\mu^- + p \rightarrow n + \nu_\mu$. The experimental approach was based on the use of a time projection chamber (TPC) that operated in pure hydrogen gas at a pressure of 10 bar and functioned as an active muon stopping target. The TPC detected the tracks of individual muon arrivals in three dimensions, while the trajectories of outgoing decay (Michel) electrons were measured by two surrounding wire chambers and a plastic scintillation hodoscope. The muon and electron detectors together enabled a precise measurement of the $\mu p$ atom's lifetime, from which the nuclear muon capture rate was deduced. The TPC was also used to monitor the purity of the hydrogen gas by detecting the nuclear recoils that follow muon capture by elemental impurities. This paper describes the TPC design and performance in detail., Comment: 15 pages, 13 figures, to be submitted to Eur. Phys. J. A; clarified section 3.1.2 and made minor stylistic corrections for Eur. Phys. J. A requirements

Host matrices with incorporated U and Pu oxides are obtained by melting of a zircon-containing heterogeneous mixture by virtue of exo effect of burning metallic fuel and are characterized by chemical analysis, spectrophotometric and radiometric methods, luminescence, X-ray microanalysis, and atomic emission ICP analysis. The material balance with respect to the incorporated radionuclides is preserved. The radionuclide distribution throughout the bulk of the matrix is nearly uniform. Metallic inclusions based on V, Fe, Si, and Mn, but containing no U and Pu, are found in the matrix. The investigated matrices are quite stable even under hydrothermal conditions (250°C, ∼30 atm): the leachability of U and Pu was determined to be 0.1-0.2 and 0.03 ppm, respectively, and that of Zr, Mn, and Fe, > 0.06 ppm.

The aim of the MuCap experiment is a 1% measurement of the singlet capture rate Lambda_S for the basic electro-weak reaction mu + p -> n + nu_mu. This observable is sensitive to the weak form-factors of the nucleon, in particular to the induced pseudoscalar coupling constant g_P. It will provide a rigorous test of theoretical predictions based on the Standard Model and effective theories of QCD. The present method is based on high precision lifetime measurements of mu^- in hydrogen gas and the comparison with the free mu^+ lifetime. The mu^- experiment will be performed in ultra-clean, deuterium-depleted H_2 gas at 10 bar. Low density compared to liquid H_2 is chosen to avoid uncertainties due to ppmu formation. A time projection chamber acts as a pure hydrogen active target. It defines the muon stop position in 3-D and detects rare background reactions. Decay electrons are tracked in cylindrical wire-chambers and a scintillator array covering 75% of 4 pi. Comment: Int. RIKEN Conf. on Muon Catalyzed Fusion and Related Exotic Atoms, April 2001, Shimoda, Japan, to be published in Hyperfine Interactions

A new experiment is under preparation with the aim to improve considerably the present knowledge of the rate Lambda(s), which should be measured on a level of 1% or better, for the basic electroweak capture reaction of a negative muon on the free proton mup(1s) --> n + nu(mu). The capture rate will be determined by measuring the lifetime of mu(-) stopped in ultra pure hydrogen at 10 bar pressure and comparing it with the lifetime of the unbound mu(+). A new experimental method was developed for this project which should allow measuring the mu(-) lifetime with at least 10 ppm precision. The basic element of the detector is operating in the hydrogen gas time projection chamber (TPC) surrounded by multi-wire proportional chambers (MWPCs) and scintillator counters. The arrival times and trajectories of the incoming muons and the outgoing decay electrons are measured with this device providing effective suppression of background. Using the TPC as an active target, we can monitor on-line the protium contamination by impurities with a sensitivity better than 10(-8). This can be done by detecting the charged products of the muon capture reaction on these impurities. It was demonstrated that the TPC and MWPCs can operate in pure hydrogen under 10 bar pressure providing gas gain up to 10 000.

The thermal expansion, thermal stability, and electrical resistivity of the Ba 1 — x M x Pb 1 + y O 3 + δ (M = Sr, Ca; 0 ≤ x ≤ 1.0, 0 ≤ y ≤ 0.2) and Ba 1 — x Pb 1 — y O 3 + δ (M' = K, La; M'' = Sc, Sb; x, y = 0.01) ceramic materials were studied between 293 and 1073 K in air. The linear thermal expansion coefficient of the ceramics was found to increase abruptly at .700 K, from (10-14) 〈 10 -6 K -1 in the range 300-600 K to (13-18) 〈 10 -6 K -1 in the range 800-1000 K. The electrical resistivity of the ceramics passes through a sharp maximum near 750 K, with the largest jump in resistivity at the compositions Ba0.6Sr0.4PbO3 and Ba0.9Ca0.1PbO3. The anomaly in thermal expansion is likely associated with the rearrangement of the lead-oxygen polyhedra in the structure of the solid solutions, and the jump in resistivity is attributable to changes in the average oxidation state of Pb ions in the surface layer of the ceramics. M x M y

The Ni, Co, Ba, and Sr profiles in the diffusion zones produced between hexagonal Y-ferrites (Ba2Co2Fe12O22–Ba2Ni2Fe12O22 , Sr2Ni2Fe12O22–Sr2Co2Fe12O22, Sr2Co2Fe12O22–Ba2Co2Fe12O22, Sr2Ni2Fe12O22–Ba2Ni2Fe12O22 , Ba2Co2Fe12O22–Sr2Ni2Fe12O22 , and Sr2Co2Fe12O22–Ba2Ni2Fe12O22) by annealing at 1470 K were used to evaluate the interdiffusion coefficients of the cations involved by the Boltzmann–Matano method over the whole composition range.

During 1994–1996, a series of μCF experiments were performed at PSI by the PSI-PNPI-IMEP-LBNL-TUM collaboration. These experiments aimed at high-precision studies of the d–μ–d fusion in D2 and HD gases in a wide temperature range. The Gatchina ionization time projection chamber has been used to detect the dd-fusion reaction products. The main parameters of the d–μ–d fusion have been measured with high absolute precision. In this report, we present the results of the final analysis of the experimental data. The obtained results are compared with the calculations based on a recent μCF-theory.

The afterglow of a Cd–Ne glow discharge is investigated theoretically and experimentally. The time-dependent electron Boltzmann equation and the balance equations for the Cd excited states and charged particles have been self-consistently solved. The temporal relaxation of the electron energy distribution function, electron, and cadmium excited states densities is reported and the influence of neon and cadmium vapor pressure on the plasma characteristics in the afterglow is studied. The modeling compares favorably with experimental results.

The heat capacity of the high-Tc superconductor YBaSrCu3O7 ‡ was measured by adiabatic calorimetry between 7 and 300 K. The temperature dependence of heat capacity was found to exhibit anomalous behavior at 94 and 255 K. The Debye characteristic temperature was determined to be θD = 369 K at low temperatures. The heat capacity data were used to assess the thermodynamic properties of YBaSrCu3O7-δ in the range 5–300 K.

An investigation in the afterglow of a Cd–Ne positive column at low and intermediate pressure is presented. The model is based on numerical solution of the time-dependent Boltzmann equation and a system of particle balance equations for the electrons, excited atoms and ions. By this model all discharge properties of interest (electron energy distribution function, electron and ion densities and the populations of both Cd and Ne excited states) are calculated in the afterglow. The populations of the excited Cd (5p 3 P 0,1,2 ) atoms are measured using time-resolved optical absorption spectroscopy. The electron density is derived by probes measurements. Model predictions are in fair agreement with measured electron density and excited-state populations.

The axial distributions of the electrons and 3p54s and 3p54p excited atoms in argon plasma columns sustained by traveling electromagnetic waves have been studied both experimentally and theoretically in the gas pressure range of 0.2–2.8 Torr. Various diagnostic methods (surface-wave interferometry, emission and absorption spectroscopy) have been used in data gathering. The theoretical model includes a self-consistent solution to the electron Boltzmann equation, electron energy balance equation, a set of balance equations for excited atoms and charged particles, the gas thermal balance equation, the wave dispersion relation, and the wave energy balance equation. The agreement between experimental data and theoretical results is very good.

Three interference asymmetry effects in the angular distributions of fragments originating from 233U fission induced by resonance neutrons were measured. The energy dependences of the asymmetry factors being studied show sizable irregularities that are associated, according to modern theory, with the interference of s and p resonances at the stage of a compound nucleus. The basic features of weak p-wave resonances in the low-energy region were obtained from a global theoretical analysis of the asymmetry factors as functions of energy. The first estimates of nuclear matrix elements of weak interaction were derived for a few p-wave resonances.

The effect of an overloading test on the remaining service life of a metallic structure exposed to corrosion is discussed. Conditions of destruction during such tests have been determined. The reduction in the service life as a result of such tests is quite considerable, but, if an overloading test does not lead to destruction, the reduction in the service life is small.

The electrical properties and thermal expansion of Nd2-x-yCexSryCuO4 solid solutions were studied in the temperature range 293–1023 K. The temperature dependences of conductivity, dielectric permittivity, and tan δ show anomalies at 488 K for Nd2Cu04 and 400 K for the solid solutions. These anomalies are accompanied by sharp changes in the linear thermal expansion coefficient

In ternary fission, besides the two main fission fragments, a third (usually light) charged particle is emitted. A triple correlation has been studied involving the momenta for a specific fission fragment p f , the momenta of the ternary particle p t and the spin of the polarized cold neutron inducing fission σ . The correlation observable B= σ ·[ p f × p t ] reverses sign upon time reversal and thus a non-vanishing value for the expectation value 〈 B 〉 could possibly be due to TRI being violated. However, final-state interactions or specific properties of the emission mechanism for ternary particles could equally well lead to a non-zero 〈 B 〉 with TRI being perfectly conserved. The reaction chosen was 233 U(n,f). An unexpectedly large correlation was observed. From the raw data the value for 〈 B 〉 is 〈 B 〉=−(0.78±0.02)×10 −3 with the sign corresponding to light fragments. Corrections for neutron polarization, geometric efficiency, resolution of detectors and background increase this figure by a factor of (1.5±0.3).

The neutron could occupy quantum stationary states if it is trapped between the Earth's gravitational field on one side and the Fermi quasi-potential of a mirror on the other side. The quantum states cause a strong variation in neutron density, both for separate energy levels and for a mixture of low-energy states. The use of a position sensitive UCN (ultracold neutron) detector allows simultaneous measurement of the position probability density distribution in the total range of interest and increases significantly the statistics, making possible such an experiment. In this article we describe a specially developed neutron spectrometer and a method of measurement of such quantum states.

For fission of 233 U induced by polarized cold neutrons the dependence of the PNC asymmetry coefficient α nf (m LF , TKE ) on light fragment mass m LF and total kinetic energy TKE was studied. Concurrently the angular distribution predicted for PNC reactions was tested. Altogether more than 2×10 10 fission events with high mass/energy resolution have been collected. This corresponds to an increase in the statistics compared to previous experiments (U. Graf, F. Gonnenwein, P. Geltenbort, et al., Z. Phys. A 351 (1995) 281 and V.A. Vesna, V.A. Knyaz'kov, E.A. Kolomenskii et al., JETP. Lett. 31 (1980) 663) by a factor of about 20. The preliminary analysis of the PNC asymmetry shows no significant variation of α nf for different fragment masses/energies, whereas the prediction concerning the angular dependence was confirmed with a precision not obtained up to now.

A self-consistent steady-state spatially averaged collisional-radiativemodel in which the rate coefficients involving electrons are calculatedfrom the solution to the electron Boltzmann equation has been developedfor describing an atmospheric pressure plasma in helium–nitrogen(He–N2) mixtures. The influence of small nitrogenconcentrations (typically less than 1%) on the discharge characteristicsis studied and compared with available experimental data. It is foundthat nitrogen is highly dissociated and that the density of metastablehelium atoms is considerably reduced by the presence of nitrogen, evenat such low concentrations.

This consideration is a conjunction of two processes: generation of recoil products and selective detection. A new type of plasma is carried out. The electron energy function distribution of the ion-guide source plasma is calculated and discussed. The properties of a laser ionization scheme detecting recoil atoms are analyzed using an optogalvanic approach. The Resonant Laser Ionization (RLI) in low temperature currentless plasma, formed by accelerated particle beam propagating through gas, will be used for the above mentioned separation. A tuned dye laser excites the studied atoms and the fast electrons ionize them. This process exceeds in cross-section the ionization from ground state which provides selectivity of IGS. The latter produces ions of almost all chemical elements. It can be used for investigating processes flowing in low temperature currentless plasma which presents a specific interest. These functions impart to the IGS the role of an Optogalvanic (OG) element, to be precise, of hol...

Based on estimates for the critical layer, a system of equations of stability of a compressible boundary layer is obtained. The system is parabolic and free from the known restriction on the step of the marching scheme related to ellipticity, which could not be eliminated within the framework of the previous method. A numerical scheme is described, and calculation results for the boundary layer on a heat-insulated plate are presented.

An investigation of cadmium-neon plasma in cylindrical axially homogeneouspositive column of a dc glow discharge at low and intermediate pressure ispresented. Electron impact excitation cross sections, heavy-particlecollision rate coefficients, and radiative decay rates for Cd–Nemixture have been assembled from the literature and summarized. Aself-consistent collisional-radiative model based on numerical solution ofthe electron Boltzmann equation coupled with a system of particle balanceequations for the electrons, excited atoms and ions, as well as the electronenergy balance equation, is developed. By this model, the electron energydistribution function, mean energy, electron density, electron mobility, anddiffusion coefficient, populations of Cd and Ne excited states and theapplied dc electric field are calculated. The populations of the excitedCd(5p3P0,1,2) atoms are measured using opticalabsorption spectroscopy. From these measurements the effective lifetime ofthe resonance state Cd(5p3P1) and the diffusioncoefficients of both metastable states Cd(5p3P0) andCd(5p3P2) are determined. The electron density isderived by probes measurements. The influence of the Cd vapor pressure anddischarge current on the main plasma characteristics is studied. Modelpredictions compare favorably with measured electron density and populationsof excited states in a wide range of discharge conditions.

A strict theoretical treatment of the electron kinetics in spatially disturbed steady state plasma near absorbing boundary is presented. The presence of an absorbing boundary is accompanied by a large electron density gradient that leads to axial dependence of the electron density, electron mobility and diffusion coefficient and to strong distortion of the electron energy distribution function. An efficient method for solving axially inhomogeneos electron Boltzmann equation under the action of a steady state electric field has been used. Both elastic and conservative inelastic collisions of the electrons with gas atoms as well as elastic electron-electron collisions are taken into account. A comparison with experimental results available is reported. Investigations are performed for rare gases and a comparison of several macroscopic quantities (electron density, mean energy, electron mobility and diffusion coefficient) is made and discussed. The applicability of the two-term Legengre polynomial expansion has been critically evaluated and discussed.

Metamorphism in the northern sector of the Main Uralian Fault (MUF) area, northern Urals, is considered by the example of the Salatim glaucophane-schist and Belokamenka kyanite-staurolite complexes. New isotope-geochronological dates for metamorphic rocks of the MUF area are presented. The obtained data evidence the existence of two metamorphic events, of Early and Late Devonian ages, which apparently correspond to the wedging-up of subduction paleozones.

A model for description of the axial structure of a surface-wave-produced and -sustained plasma based on numerical calculation of a complete set of electrodynamic and kinetic equations is presented. The model includes a self-consistent solution to the electron Boltzmann equation, a set of particle balance equations for electrons, excited atoms, atomic and molecular ions, as well as Maxwell's equations with appropriate boundary conditions. A gas thermal balance equation is used to predict the neutral gas temperature self-consistently. Precise calculations of discharge characteristics of an argon plasma column sustained by an azimuthally symmetric surface wave at low and intermediate gas pressures have been performed. A comparison with available experimental data is done in order to test the validity of the model.

Using the saddle-point method, asymptotics of time evolution for spatially localized three-dimensional intrinsic disturbances are determined. Criteria of absolute instability are established for the case of a branching dispersion relationship. Calculation results for the regions of existence of instability for a flat-plate boundary layer forRe→∞ andM=10 are presented.

The constriction of the positive column of a dc glow discharge in argon at high pressures is analyzed using the continuity equations for the charged particles and the gas thermal balance equation coupled with the local electron Boltzmann equation and a detailed collisional-radiative model for the atomic and ionic species. Contrary to the other existing models of the constriction in inert gas, the present model is self-consistent and fully detailed, and provides a quantitative description of all the discharge properties. The numerical techniques used to solve the boundary value problem corresponding to our set of equations are discussed in detail. The transition from the diffuse to the constricted state and the properties of this latter state are investigated. The model predicts the existence of multimodal solutions for the discharge parameters as a function of the discharge specific power, within a limited range of values of the latter above a critical value, which explains the observed abrupt changes in the discharge parameters and the hysteresis associated with constriction. The radial distributions of the gas temperature and of the densities of all neutral and charged species considered are determined along with various other discharge characteristics, such as the steady-state discharge maintenance electric field, as a function of the discharge operating parameters. The results for argon show satisfactory agreement with data from experiments. A few model simulations are further presented that enable one to gain physical insight on the relevant kinetic processes of constriction in argon. Such simulations are instrumental to understanding also the mechanisms of constriction in the other inert gases.

We report on the results of an experiment aimed at observing muon-catalyzed d 3He-fusion with a setup previously used for studies of the muon-catalyzed dd-fusion. The basic element of the setup is a high pressure ionization chamber operating as an active target. In this experiment the chamber was filled with an HD + 3He (5.6%) gas mixture at 13.2 bar pressure and 50 K temperature. These conditions were chosen as optimal for formation of the 3Heμd-molecules with a low level of background from the d-μ-d fusion. The chamber was exposed to the negative muon beam at PSI. During a 3-week data-taking period, 9.7 × 108 muon stops have been selected. The analysis of the data was able to determine a new upper limit for the d 3He-fusion rate in the 3Heμd-molecule (λf≤ 6× 104 s-1), which is more than three orders of magnitude lower than the previously existed limit.

We present the results of precision measurements of dμ spin-flip rates in pure D2, in pure HD gas, and in the non-equilibrium and equilibrium H2+D2 gas mixtures. The experiments were performed at PSI in 1994-1996 using the high pressure ionization chamber from Gatchina as a 100% efficient detector of the charged fusion products. The measurements have been carried out in the temperature range 28-300 K, at gas density of 5% of LHD. In pure deuterium, the measured temperature dependence of the spin-flip rate allowed us to separate the two components (resonant and non-resonant) of the spin-flip processes. From the experiments in H/D mixtures we have measured the non-resonant spin-flip rate in collisions of dμ-atoms with HD molecules. Comparison with the theory revealed considerable disagreement in the case of non-resonant spin-flip in collisions of the dμ-atoms with D2 molecules.

We present the results of an experiment performed at PSI to investigate muon catalyzed fusion in pure deuterium gas of 5% density (LHD) at temperatures ranging from 28 K to 350 K. Using a new high pressure ionization chamber the reactions dd → n + 3He and dd → p+t were observed with 100% detection efficiency. The rates of dμd formation were measured with the absolute precision of 1% and the μd spin-flip rates with 0.5%. The temperature dependence of molecular formation and spin-flip rates display pronounced resonance structures. A preliminary fit based on the Vesman mechanism of resonant muonic molecule formation was carried out yielding a dd fusion rate of 3.5·108 s-1 and a hfs splitting energy \(\delta \varepsilon _{d\mu d} \) of 24.3 meV, both in good agreement with the theory.

The results of an experiment on muon catalyzed dd-fussion in HD gas are presented. The experiment was performed at the muon beam of PSI using a high-pressure ionization chamber filled with pure HD-gas of low D2 concentration on the level 1%, at temperatures 50, 150 and 300 K. The non-resonant character of ddμ-molecule formation on HD molecules was confirmed by measuring the ratio of yields of the two ddμ-fusion channels, R=Y(3He,n)/Y(3H,p), which proved to be close to unity. The ddμ formation rate was found to vary from λddμ-HD=0.05· 106 s-1 at T=50 K to λddμ-HD=0.12· 106 s-1 at T=300 K, in agreement with the theoretical prediction. A prominent peak at t

These investigations were performed to test the modern theory and to obtain first estimates of nuclear matrix elements of weak interaction and the main parameters of p -resonances. Combined investigations of the space parity non-conservation effect of 235 U fission fragment emission and the interference effects of the forward-backward and left-right asymmetries were carried out over the range of neutron energies from 0.02 eV to 90 eV. The experimental results are found to be in good agreement with the theory. The first estimates of the nuclear matrix element of the weak interaction for three p -resonances and the main parameters of some low energy p -wave resonances are obtained from a combined theoretical description of all experimental data.

The muon transfer rate $$(\tilde \lambda _{d{\text{ }}^{\text{3}} {\text{He}}} )$$ from deuterium to 3 at temperatures of 39.5 K and 50.0 K, respectively, has been determined as a by-product of the experiment aimed to search for muon catalyzed d 3He-fusion. The measurements were performed in the muon beam at PSI with a multi-anode high pressure ionization chamber as a target and detector of the incoming muons and the charged reaction products. The chamber was filled with the HD + 3He(5.6%) gas mixture of 9.21% LHD density. The analysis of time distributions of dd-fusion events was able to determine the transfer rates: $$\tilde \lambda _{d{\text{ }}^{\text{3}} {\text{He}}} $$ (50 K)=(2.32± 0.09)× 108 s-1, $$\tilde \lambda _{d{\text{ }}^{\text{3}} {\text{He}}} $$ (39.5 K)=(2.33± 0.16)·108 s-1. These values, normalized to liquid hydrogen density (LHD, 4.25· 1022 atoms/cm3), significantly exceed the transfer rates at room temperature, in agreement with theoretical predictions.

Muon capture on hydrogen gives a unique possibility for a measurement of the pseudo-scalar form factor gp(qc2 = -0.88 mμ2) of the nucleonic weak current, thus providing a sensitive test of the QCD chiral symmetry perturbation theory which predicts the value of this form factor with a precision of Δgp/gp≃ 2%. For adequate comparison with theory, the muon capture rate Λc should be measured with a precision of ΔΛc/Λc ≤ 1%, that is an order of magnitude better than the precision of the present world data. We report on the project of an experiment designed to provide the required precision. Also, we present the final result of our previous experiment on a high precision measurement of the μ3He capture rate and compare this result with the PCAC prediction.

In the Middle Urals, volcanic-arc and back-arc basin rocks of Ordovician to Devonian age occur in the Tagil Synform. These outboard terranes were thrust westwards in the late Carboniferous onto continental margin associations of late Proterozoic and Palaeozoic age, now exposed in the Central Uralian Uplift. The Main Uralian Fault coincides approximately with the suture separating the outboard terranes from the East European Platform margin. New fieldwork in the hinterland of the Middle Urals in the area east of the Tagil Synform has found structural evidence favouring E-directed thrusting of accreted terranes and eugeoclinal allochthons in the late Palaeozoic. The upper tectonic units are composed of ophiolite melange and volcano-sedimentary rocks of Ordovician to Devonian age; they are thrust onto high-grade gneisses, some of possible microcontinental affinities, extensively intruded by mid-Palaeozoic granitic plutons. The nappes in the hinterland are refolded by major upright antiforms and synforms that fold the entire tectonostratigraphy. After thrust assembly, all tectonic units east of the Main Uralian Fault were intruded by late Carboniferous to early Permian granites. Reflection seismic profiles (recorded to 8 s TWT), recently reprocessed at Cornell University, image the major fold structures and demonstrate that they are restricted to the upper crust, being underlain by an extensive zone of flat-lying middle crustal reflectivity. At 10–15 km depth the latter appears to truncate all structures, including the late- to post-tectonic granitoids and extensional faults, east of the Main Uralian Fault. Previous studies (potential-field, refraction- and wide-angle-reflection seismics) have identified an anomalously deep crust under the Tagil Synform and have concluded that the root zone of the orogen is located beneath this belt. The new evidence presented here supports this interpretation, with back-thrusting of the oceanic rocks eastwards over Palaeozoic accreted terranes. © 1998 John Wiley & Sons, Ltd.

The muon capture rate in the reaction mu- 3He -> nu + 3H has been measured at PSI using a modular high pressure ionization chamber. The rate corresponding to statistical hyperfine population of the mu-3He atom is (1496.0 +- 4.0) s^-1. This result confirms the PCAC prediction for the pseudoscalar form factors of the 3He-3H system and the nucleon., 13 pages, 6 PostScript figures

Dr P Pramatarov and Dr M Stefanova, of the Bulgarian Academy of Sciences, Institute of Solid State Physics, 72 Tzarigradsko Chaussee blvd, 1784 Sofia, Bulgaria, should have been acknowledged as co-authors of the above paper.

We report the results of an analysis of time and energy distributions of fusion products obtained in experiments on dtµ-fusion of HD molecules in triple H/D/T mixtures performed in Gatchina in 1985 and at PSI in 1989–92 with a high-pressure ionization chamber and neutron detectors. With different concentrations of tritium, 2.7 and 0.05%, it was possible to evaluate the rate of dtµ formation from the spin statesF=0 andF=1 of tµ atoms. The combined analysis of these experiments provided information about the contribution of epithermal dtµ formation to the initial part of the time spectra, which depends on the ratio of the exchange rates (λpt/λpd)eff ·ct/cd=(λpt/λpd+b)·ct/cd, whereb is the fraction of the fast muon dt-exchange at high energy of dµ atoms

In this article we report the results of an experiment performed in 1993 at PSI. The goal was to determine the absolute rate of nuclear muon capture by3He. In the experiment we used a new technique recently developed at Gatchina. As a preliminary result from this experiment we obtainedλ c=(1496±3(stat)-3(syst)) s−1.

A new experiment was started at PSI aiming for high-precision and complete studies of dµd fusion in D2, HD and D2/H2 gas mixtures. A high-pressure ionization chamber surrounded by a set of neutron counters is used to observe dd-fusion at temperatures between 25 and 350 K. Here we report preliminary results from the first test run with pure D2 filling.

The triton energy spectrum of the muon capture reaction mu(3)He --> t + v(mu), where mu(3)He is the ground state of muonic He-3, has been measured by means of a high-pressure ionization chamber in order to investigate a possible heavy v admixture into the mu flavor with high sensitivity. The upper limit of the mu-heavy v(i) mixing matrix element squared was obtained to be U-mu i((2) less than or equal to 10(-3) for heavy neutrino masses in the range 25 less than or equal to E(ov) less than or equal to 75 MeV.

The rates of the breakup reactions Lambda B(He-3) and Lambda B(He-4) in nuclear muon capture by He-3 and He-4 have been measured. The measurements were performed on the muon beam of PSI with a multi-anode high-pressure ionization chamber filled with isotopically pure He-3 or He-4 at 120 bar. The chamber was used as a target and detector for both the incoming muons and for the charged reaction products (tritons, deuterons and protons) of the breakup reactions mu(-) + He-3 --> d + n + v(mu), p + 2n + v(mu) and mu(-) + He-4 --> t + n + v(mu), d + 2n + v(mu), p + 3n + v(mu). Our statistics, about 5 x 10(5) of breakup events, provides a possibility to improve the precision of evaluated rates. The preliminary results: Lambda(B)(He-3) = 720 +/- 70 s(-1), Lambda B(He-4) = 415 +/- 40 s(-1) are compared to theoretical predictions and to previous experiments.

We propose to study a number of open problems in ddµ and pdµ fusion using the new high-pressure ionization chamber for charged particle identification in coincidence with the n-/e-counter array for the detection of neutrons and µ-decay electrons. Our first objective will be a precise measurement of the absolute rates of resonant and non-resonant ddµ formation in D2 and HD-gases and their temperature dependence from 40 to 350 K. Both output channels of the dd-reaction:3He + n and t + p will be observed and their ratio sensitive to contributions of S and P-waves will be determined. Simultaneously, we shall investigate the pdµ-cycle and determine the absolute pd-fusion yields in different molecular H/D compositions, observing tritons from nuclear muon capture in3Heµ: pdµ →3Heµ + γ. We have developed a special system for the preparation of HD-gas with high concentration (96%) of HD and a purity (10−6).

1. In connection with the historically established economic conditions and existing agreements with neighboring countries, the cascade of Vakhsh hydrostation was designed on the basis of operating conditions in an irrigation regime and cannot provide Tajikistan's own need for power in the winter, the deficit of which is 4 billion kWh/yr. The traditional methods of solving this problem call for the construction of either an irrigation reregulator in the lower course of the river or a hydrostation operating in a power compensator regime in its upper course. Both these variants require vast expenditures of material and financial resources and provide an effect just due to one particular hydro development. 2. The natural conditions of Tajikistan created the unique possibility of increasing the effectiveness of the combined operation of the Vakhsh cascade by constructing a tunnel conduit and using the runoff of the Pyandzh River in operating the Vakhsh hydrostations. With minimum construction costs the power effect of the cascade in this case increases substantially since it is achieved due to the repeated use of Pyandzh River water at all stations of the cascade and without any detriment for irrigation. 3. Realization of the proposed project will increase the total power production of the cascade for all hydrostations specified by the scheme depending on the degree of streamflow regulation by the Pyandzh reservoir. The cost effectiveness of the proposed project is an order higher than that of the traditional variants. Even for the stations operating today on the cascade its effect is comparable to the effect of the Nurek hydrostation with respect to all indices. Here the total cost of the tunnel conduit together with the dam is an order lower than the cost of the Nurek hydro development.

A simple kinetic model of the Ne-H2 Penning-Plasma Laser (PPL) (NeI 585.3 nm) is proposed. The negative glow of a hollow cathode discharge at intermediate pressures is considered as the active medium. The balance equations for the upper and lower laser levels, electrons, ions and electron energy are solved. The dependences of the laser gain on the discharge conditions (Ne and H2 partial pressures, discharge current) are calculated and measured. The calculated values are in a good agreement with the experimental data.

Radioactive contamination of the environment is possible during operation of nuclear power plants and the utilization of radionuclide sources in the economy. The problem of decontaminating the surfaces of industrial objects and environmental objects which are contaminated by radionuclides can be solved by different methods of depending on the character of the object: chemical treatment of metallic surfaces of equipment parts by application of different washing fluids, mechanical removal of contaminants or washing contaminants off with a jet of liquid, as well as adding different abrasive additives, the use of film-forming substances for sorption and removal of the decontaminating layer from the surface being cleaned, and other methods.