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The study evaluates the psycho-physiological status and sociopsychological characteristics of humanitarian and technical students working for their bachelor's degree. The longitudinal study featured male and female students of technical university majoring in various humanitarian and technical sciences. In their analysis of neurodynamic, cognitive and psychodynamic parameters, the authors assessed mechanical, semantic and image types of memory, mental alertness, mental performance efficiency, speed of sensomotor reaction to photic stimulus, and nervous processes. They used A. K. Osnitsky’s Method of Evaluation of Social and Psychological Adaptation, Ch. D. Spielberger and Yu. L. Khanin’s Assessment Method of Reactive and Personal Anxiety Level and H. Eysenck’s tests on stress resistance and temperament assessment. The study revealed that both male and female students of different specialties underwent certain psycho-physiological and socio-psychological changes resulting from their adherent personal characteristics and from the influence of the specialty.

The physical processes associated with deep welding are analyzed. A two-dimensional numerical model is proposed for the interaction of the laser beam with the medium in the vapor channel. The following processes are considered: heat and mass transfer; absorption and reradiation of the beam’s energy by the plasma; interaction of the plasma with the channel walls; and heat transfer to the cold sample. The model establishes a quantitative relation between the welding conditions and the results of butt welding. That decreases the expenditures in the development of laser-welding processes.

The results of the researches which determine the dependence of gas-thermal coating porosity on the laser radiation parameters are given in the article. The coatings which are based on the metallic (PN-85-U-15) and non-metallic (Al2O3) components were analyzed. The quantitative assessment of porosity modification were realized by means of the based on Visual Studio 2008 program. This image processing program allows to compare the microstructure of the occupied by pores and coating material areas pixel-by-pixel. It has been established that the action of laser radiation leads to reduction of average porosity of gas-thermal coating. This reduction is: 1. the porosity in the initial position for coating of a PN 85-U-15-based alloy is 17%; after the laser treatment it’s 5-8%; 2.- the porosity in the initial position for ceramic coating of Al2O3is 24,5%; after the laser treatment it’s 15-18%.

A computational method is used to study processes for obtaining super-fragmented metallic materials and products made from them (strands or filaments reduced to nanometers). The article examines three problems concerning the super-fragmentation of long metallic bodies by electrostimulation rolling in grooves and passes. Super-fragmentation is used to obtain experimental metallic nanomaterials and products that could not be obtained by traditional methods of rolling.

By the example of commencement and development of two successive substorms on August 1, 1998, the mechanism resulting in the initiation of auroral processes (substorms) is discussed. These events were chosen due to the favorable position of satellites in the solar wind, magnetosphere, and plasma sheet, as well as due to the availability of satellite and ground-based observation data.

The investigations of the possibility of intensifying the processes of combustion in high-velocity flows of kerosene-air mixtures with the aid of electric discharges are used for studying the structure of flow and the distribution of products of plasma-chemical reactions behind a screen sloped toward the flow, with an auxiliary working medium in the droplet-gas and gas phases (kerosene, propane) being injected into the space under said screen. The experiments are performed at Mach number M = 2 and static pressure of 260 torr. The distribution of static and total pressure in the region behind the screen and the field of Mach number are obtained in the absence of discharge, and the distribution of kerosene under the screen and in the wake behind the screen is visualized. A discharge with a current of 1 A at a voltage of about 2 kV is initiated above and behind the screen. The experimental conditions and geometry are found, at which the discharge behind the screen is spatially distributed. For these conditions, the distribution of the products of plasmachemical reactions in the case of injection of kerosene and propane is studied.

This article discusses possible alternative methods of making bars and wire without the use of conventional drawing operations. Thanks to use of the features and capabilities of the electrically stimulated deformation of metals, a foundation has been established for developing new approaches to the production of bars and wire products.

A method is given for the calculation of Ridberg—Klein—Rees potentials (RKR potentials) of internuclear interaction of diatomic molecules, which is based on a combination of numerical and analytical computer codes. A calculation of potentials of internuclear interaction is performed for 32 electron states of N2, N 2 + , C2, CO, CO+, and CN molecules of practical interest as regards problems in aerophysics of interplanetary space vehicles. Complete spectral information is given for the calculation of potential curves, which may be used for unique comparison of the results of calculations of internuclear potentials obtained by different methods.

The depth profiles of high dosage 52Cr+ and 51V+ ions implanted in (100) crystalline silicon after thermal anneal at temperatures between 300 °C and 1000 °C are studied by secondary ion mass spectrometry and cross-sectional transmission electron microscopy. At dosages of 1×1015 ions/cm2 and above, the surface layer of silicon substrate is amorphorized. During the subsequent thermal annealing, the depth profiles of the implanted ions are strongly coupled with the solid phase epitaxial growth of amorphous silicon. Silicide precipitate formation is important to understand the differences between Cr and V diffusion. After anneal of the 1×1015 ions/cm2 implanted samples at 900 °C and 1000 °C, most of the Cr has left the silicon, but only 10% of the V has escaped. The 1×1014 ions/cm2 Cr-implanted sample shows Cr ions exist only near the surface after 1000 °C anneal. The V-implanted sample, on the other hand, only shows a narrowing of the V profile after 1000 °C anneal.

The inertialess flow of a viscoplastic medium with a scalar determining relation in Ilyushin-Bingham form is investigated. The presence of rigid zones and their deformation during the motion are taken into account. A linearized initial boundary-value problem in the first approximation in the inhomogeneity parameter is formulated. The cases of spatial and plane deformation are considered. In the latter case, introducing the stream function makes it possible to find an analogy with the equations of Hamiltonian mechanics and the concept of chaos. Finding the law of motion, or trajectory, of each particle allows conclusions to be drawn concerning the chaotic state and the onset of mixing.

The deformation stability relative to small perturbations is analyzed for weakly inhomogeneous viscous media on the assumption that both the main flow and perturbation field are three-dimensional. To test the damping or growth of initial perturbations, sufficient estimates based on the use of variational inequalities in different function spaces (energy estimates) are obtained. The choice of function space determines the measures of the parameter deviations, which may be different for the initial and current parameters. The unperturbed process chosen is a fairly arbitrary unsteady flow of homogeneous incompressible viscous fluid in a three-dimensional region of Eulerian space. At the initial instant, not only the kinematics of the motion but also the density and viscosity of the fluid are disturbed and the medium is therefore called weakly inhomogeneous. On the basis of the integral relation methods developed in recent years, sufficient integral estimates are obtained for lack of perturbation growth in the mean-square sense (in theL 2 space measure). The rate of growth or damping of the kinematic perturbations depends linearly on the initial variations of the kinematics, density and viscosity. Illustrations of the general result are given.

A substantial percentage of the metal made today is subjected to shaping operations—mainly rolling. The rolling of sheets, plates, strip, bars, and other products is the most productive and most economical method of plastically deforming metallic semifinished products. However, numerous (sometimes at least several dozen) heatings and annealings are needed to obtain final products in the form of sheets, strip, and small-diameter bars. This sharply reduces the productivity of the process, appreciably increases energy and labor costs, and requires more production space and metal-intensive equipment.

The equations of motion of a continuum in a thin layer are derived for a given functional dependence of the stress tensor on the strain rate tensor. The general problem of viscoplastic flow is considered in the thin-layer approximation for boundary surface material points travelling in the lateral direction in a predetermined fashion.

The problem of the flow of a viscoplastic medium between two parallel circular plates in translatory coaxial relative motion is solved. The Bingham model [1] of a viscoplastic medium is assumed. The problem is solved in the inertialess thin layer approximation [2] for arbitrary values of the viscosity coefficient and yield stress.

One of the methods of extraction of remaining reserves used in JSC “Gazpromneft-Noyabrskneftegaz” is sidetrack operations which also enable to involve fishing well stock of oil fields. Efficiency of these arrangements depends mainly on cooperation of specialists in geology, field development and drilling. At present, interaction pattern between subdivisions of the Company and contractor drilling organizations is developed which allows to perform full cycle of implementation of sidetracks starting with selection of wells and finishing geological support of drilling operations. Permanent field development monitoring of perspective oil deposits, application of the developed well selection technique and analysis of geological features using state- of-the-art program packages of seismic interpretation, geological and simulation modeling packages encouraged successful drilling jobs in the selected wells, getting agreement of actual flow rates and forecast and, as a result, increase of incremental oil production of the Company.

A new stereospecific method for 1,2- cis -glycosylation involves the reaction of 1,2- trans -glycosyl thiocyanates with sugar trityl ethers in the presence of triphenylmethylium perchlorate. The method has been applied to give disaccharide derivatives with (1→6), (1→4), (1→3), and (1→2) linkages.

The completely stereoregular polysaccharide, α-(1-6)-D-glucan, has been synthesised using a new highly stereospecific type of polycondensation process - trityl-thiocyanate polycondensation.

A new stereospecific method for 1,2- cis -glycosylation involves the reaction of 1,2- trans -glycosyl thiocyanates with sugar trityl ethers in the presence of triphenylmethylium perchlorate. The method has been applied to give disaccharide derivatives with (1→6), (1→4), (1→3), and (1→2) linkages.

Instrumentation for heavyion accelerators; Instrumentation for particle accelerators and storage rings-high energy; Cherenkov and transition radiation; Gaseous detectors; Liquid detectors; Photon detectors for UV, visible and IR photons; Scintillators, scintillation and light emission processes; Solid state detectors; Calorimeters; Cherenkov detectors; dE/dx detectors; Gamma detectors; Large detector systems for particle and astroparticle physics; Particle identification methods; Particle tracking detectors; Photon detectors for UV, visible and IR photons; Spectrometers; Time projection chambers; Timing detectors; Transition radiation detectors; Analysis and statistical methods; Computing; Data processing methods; Data reduction methods; Pattern recognition, cluster finding, calibration and fitting methods; Simulation methods and programs; Software architectures; Detector alignment and calibration methods; Detector cooling and thermo-stabilization; Detector design and construction technologies and materials; Detector grounding; Manufacturing; Overall mechanics design; Special cables; Voltage distributions. ALICE (A Large Ion Collider Experiment) is a general-purpose, heavy-ion detector at the CERN LHC which focuses on QCD, the strong-interaction sector of the Standard Model. It is designed to address the physics of strongly interacting matter and the quark-gluon plasma at extreme values of energy density and temperature in nucleus-nucleus collisions. Besides running with Pb ions, the physics programme includes collisions with lighter ions, lower energy running and dedicated proton-nucleus runs. ALICE will also take data with proton beams at the top LHC energy to collect reference data for the heavy-ion programme and to address several QCD topics for which ALICE is complementary to the other LHC detectors. The ALICE detector has been built by a collaboration including currently over 1000 physicists and engineers from 105 Institutes in 30 countries. Its overall dimensions are 16x16x26 m3with a total weight of approximately 10 000 t. The experiment consists of 18 different detector systems each with its own specific technology choice and design constraints, driven both by the physics requirements and the experimental conditions expected at LHC. The most stringent design constraint is to cope with the extreme particle multiplicity anticipated in central Pb-Pb collisions. The different subsystems were optimized to provide high-momentum resolution as well as excellent Particle Identification (PID) over a broad range in momentum, up to the highest multiplicities predicted for LHC. This will allow for comprehensive studies of hadrons, electrons, muons, and photons produced in the collision of heavy nuclei. Most detector systems are scheduled to be installed and ready for data taking by mid-2008 when the LHC is scheduled to start operation, with the exception of parts of the Photon Spectrometer (PHOS), Transition Radiation Detector (TRD) and Electro Magnetic Calorimeter (EMCal). These detectors will be completed for the high-luminosity ion run expected in 2010. This paper describes in detail the detector components as installed for the first data taking in the summer of 2008. © 2008 IOP Publishing Ltd and SISSA.

The relationships between Boron Interstitial Cluster (BIC) evolution and boron diffusion in relaxed Si0.8Ge0.2 have been investigated. Structures were grown by Molecular Beam Epitaxy (MBE) with surface boron wells of variant composition extending 0.25 [.proportional]m into the substrate, as well as boron marker layers positioned 0.50 [.proportional]m below the surface. The boron well concentrations are as follows: 0, 7.5×1018, 1.5×1019, and 5.0×1019 atoms/cm3. The boron marker layers are approximately 3 nm wide and have a peak concentration of 5×1018 atoms/cm3. Samples were ion implanted with 60 keV Si+ at a dose of 1×1014 atoms/cm2 and subsequently annealed at 675°C and 750°C for various times. Plan-view Transmission Electron Microscopy (PTEM) was used to monitor the agglomeration of injected silicon interstitials and the evolution of extended defects in the near surface region. Secondary Ion Mass Spectroscopy (SIMS) concentration profiles facilitated the characterization of boron diffusion behaviors during annealing. Interstitial supersaturation conditions and the resultant defect structures of ion implanted relaxed Si0.8Ge0.2 in both the presence and absence of boron have been characterized.

In prior works, we demonstrated the phenomenon of fluorine-enhanced boron diffusion within self-amorphized silicon. Present studies address the process dependencies of low temperature boron motion within ion implanted materials utilizing a germanium amorphization. Silicon wafers were preamorphized with either 60 keV or 80 keV Ge+ at a dose of 1×1015 atoms/cm2. Subsequent 500 eV, 1×1015 atoms/cm211B+ implants, as well as 6 keV F+ implants with doses ranging from 1×1014 atoms/cm2 to 5×1015 atoms/cm2 were also done. Furnace anneals were conducted at 550°C for 10 minutes under an inert N2 ambient. Secondary Ion Mass Spectroscopy (SIMS) was utilized to characterize the occurrence of boron diffusion within amorphous silicon at room temperature, as well as during the Solid Phase Epitaxial Regrowth (SPER) process. Amorphous layer depths were verified through Cross-Sectional Transmission Electron Microscopy (XTEM) and Variable Angle Spectroscopic Ellipsometry (VASE). Boron motion within as-implanted samples is observed at fluorine concentrations greater than 1×1020 atoms/cm3. The magnitude of the boron motion scales with increasing fluorine dose and concentration. During the initial stages of SPER, boron was observed to diffuse irrespective of the co-implanted fluorine dose. Fluorine enhanced diffusion at room temperature does not appear to follow the same process as the enhanced diffusion observed during the regrowth process.

The polycondensation of 1,2-0-exo-cyanethylidene-4,6-di-0-acetyl-3-0-trityl-α-D-glucopyranose (I) was accomplished in the presence of triphenylmethylium perchlorate in CH2Cl2 under the pressure of 14 kbar. The reaction was performed in the “frozen solution” after the phasic transition of the system, and led to the product of polycondensation which, after the removal of the protecting groups, gave the exactly regio- and stereo-regular β-(1−3)-D-glucan.

The highly stereoselective synthesis of a 1,2-cis-glycosidic linkage is difficult and a satisfactory solution remains a problem in the synthetic chemistry of carbohydrates. Recently, we proposed a new approach to specific 1,2-cis-glycosylation, by using l,Ztruns-glycosyl thiocyanates with a non-participating substituent at C-2 as the glycosylation reagent’-3. We report now the application of this approach to the stereospecific synthesis of l,Zcis-glycosides of 2-amino sugars, which can also be regarded as a difficult problem [cf. ref. 41. The corresponding 1,2-truns-2-azido-2-deoxyglycosyl thiocyanate was used as glycosyl donor with subsequent conversion of the azido into an amino group. The stereospecific synthesis of 1,2-cis-glycosaminides is demonstrated by the synthesis of derivatives of a-D-glucosaminyl-o-glucoses with different types of glycosidic linkages. 3,4,6-Tri-0-acetyl-2-azido-2-deoxy-P-D-glu~pyranosyl thiocyanate (1) has been obtained by treatment of the known 3,4,6-tri-O-acetyl-2-azido-2-deoxy-a-D-glucopyranosyl bromide5 (5.6 mmol) with KSCN (16.9 mmol, dried in vacua at llO’C> in the presence of U-crown-6 (1.7 mmol, dried in vacua at 20°C) in acetone (6.5 h, TLC control, 20°C). After evaporation, addition of benzene, filtration through SiO,, evaporation, and chromatography (SiO,, benzene-ether gradient), 1, mp 124.5-125S”C (from ether-hexane), [(r]? -84.4” (c 1.15, CHCI,), was isolated in 71% yield *; v,,, 2162 cm-’ (SCN), 2116 cm-’ (N,); ‘H NMR data: 6 5.19 (dd, 3 H, I,,, 9.5 Hz, H-31, 5.09 (dd, 1 H, J4,5 9.5 Hz, H-4), 4.55 (d, 1 H, J,,, 9.5 Hz, H-l), 4.16-4.30 (m, 2 H, J5,6a 5, &, 2.5, J6a,6b 10 Hz, H-6a,6b), 3.86 (d, 1 H, I,,, 9.5 Hz

The motion of large structures around their centers of mass is investigated when the center of mass moves in the central gravitation field along Kepler orbit. The structure is modeled as a viscoelastic solid with high stiffness; the characteristic decay time of its free elastic oscillations is assumed to be small compared to orbital period of the center of mass. Linear elasticity is used, with frictional dissipation being introduced through Rayleigh function. The method of modal analysis together with the method of small parameter are used for solving problems involved.