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An algorithm for estimating the energy of a radio pulse when measuring a superconducting system qubit–resonator consisting of a superconducting resonator and a coupled qubit is proposed. The algorithm is based on the use of complete sufficient statistics and does not require a priori information about the level of additive white Gaussian noise in the process, as well as about the amplitude, initial phase, and temporal position of the radio pulse. The estimates are effective and consistent. The efficiency of the algorithm is estimated by means of computer simulation. [ABSTRACT FROM AUTHOR]

The effect of pulsed electrolysis on the electrodeposition of Cu–Sn alloy from the sulfate–sulfuric acid electrolyte is studied. It is shown that the codeposition of copper and tin is observed only at the potentials, which provide the discharge of copper(II) ions under the diffusion control. The transient time of electroreduction of copper(II) ions and the concentrations of Cu2+ ions in the near-cathode region in the pause are calculated. It is shown that a decrease of the pause duration leads to the alloy deposition at lower current densities. It is found that the use of pulsed electrolysis enables one to raise significantly (by 3 times) the range of cathodic current densities for production of high-quality yellow-bronze coatings. The effect of pulse duration and amplitude on the qualitative and quantitative compositions of the alloy is determined. [ABSTRACT FROM AUTHOR]

Methods of scanning electron microscopy, potentiodynamic polarization, and X-ray diffraction analysis were used to study the kinetic features of the electrodeposition process of the copper-tin alloy from an oxalic acid electrolyte and analyze the structure, composition, and luster of coatings formed under sonochemical treatment conditions at varied power of the ultrasonic field and current load. The ultrasonic treatment with power of 8-40 W dm-3 makes it possible to 2-8 times intensify the cathodic process and obtain coatings containing 10-15 wt % tin with luster of 20-40%. The specific content of tin in a coating being formed is nearly independent of the ultrasound power and grows with increasing the cathodic current density. [ABSTRACT FROM AUTHOR]

Potentiodynamic polarization method was used to study kinetic specific features of the electrodeposition of copper under a sonochemical treatment of a sulfuric acid electrolyte. The working current densities, scattering power of the electrolyte, the structure, microhardness, and luster of the formed coatings were determined depending ultrasonic field power and the presence of a thiourea additive in the electrolyte. It was found that it is advisable to perform the sonochemical electrodeposition of copper from a sulfuric acid electrolyte with addition of 0.003 g dm-3 of thiourea at a current density of 2 A dm-2 and ultrasonic vibration power of 8 W dm-3. [ABSTRACT FROM AUTHOR]

Research on the structure of vanadium-containing glaze coatings obtained using spent vanadium catalysts from sulfuric acid production is reported. The chemical and phase compositions of glazes are studied. The colored glazes developed can be used in enterprises producing stove tiles, majolica, and artistic ceramic articles. [ABSTRACT FROM AUTHOR]

The results of clinical and experimental morphological studies of regenerates forming after replacement of large defects of the abdominal wall and tibia with implants from different materials (polytetrafluoroethylene, reperene, prolene, titanium, and titanium nickelide) are analyzed. Study of the regenerate histology and fibroarchitectonics has shown good prospects of mesh constructions from titanium nickelide for effective surgical repair of these defects. The use of this implant seems to be theoretically well-based and promising, particularly under conditions of suppurative infection and low individual reparative regenerative potential. [ABSTRACT FROM AUTHOR]

The paper addresses forced vibrations in piping subsystems, which are induced due to the formation and separation of turbulent vortices in the flow of a fluid being transported. The excitation frequency is not a constant number but can take on values from a certain range, thus leading to difficulties and ambiguities in the vibration analysis of piping. To solve this problem, a so-called energy approach is put forward which enables one to determine the most physically governed frequencies of forced vibrations. The approach essentially consists in searching for the natural frequencies and modes of the fluid hydrodynamic vibrations whereby the minimum amount of energy leaves the piping subsystem, while the maximum one remains inside. The validity of the proposed approach is verified by test examples. The proposed methods have been used to analyze piping forced vibrations induced by turbulent vortices in the steam flow in the secondary coolant piping of nuclear power plants with WWER-1000 reactor. Natural frequencies and modes of mechanical, hydrodynamic, and coupled hydrodynamic vibrations have been determined; some recommendations of how to minimize the level of vibrations have been worked out. [ABSTRACT FROM AUTHOR]

The paper describes the method of initial parameters which is used for stress analysis of complex branched piping systems under static loading as well as under natural and forced harmonic vibrations, including the case of kinematic loading by displacement amplitudes. For the purpose of modeling arbitrary curved elements, in particular three-dimensional ones, the authors propose an inertialess rotary element of zero length, which turns coordinate axes of neighbor elements. The paper demonstrates the potentialities of the method for vibrodiagnostics of piping. [ABSTRACT FROM AUTHOR]

An algorithm for detecting spectral peak absorption in the secondary radiation from an object containing nitrogen compounds is proposed. The algorithm is based on the statistical invariance principle and has the property of automatically adjusting to signal-noise parameters. The algorithm was tested by simulation modeling and was shown to be applicable to real secondary-radiation spectra. The algorithm and the associated experimental hardware make it possible to implement a fundamentally new method for the automatic detection of nitrogen-containing compounds. [ABSTRACT FROM AUTHOR]

We have performed calculations of stress-strain state of cable-stayed aerial pipeline crossing in the operation state and of the additional effect of the inspection gauge application. In order to assess efforts in the pipe and cable stays of the aerial crossing, we apply analytical solutions combined with numerical simulations using the 3D PipeMaster software system. This comprehensive analysis allows one to assess stresses in the critical zones of the crossing, as well as to develop recommendations on strengthening the structure of the aerial crossing before its in-line inspection. [ABSTRACT FROM AUTHOR]

We propose a procedure for the numerical analysis of the stress-strain state and criteria of its admissible state in the course of repairs of the air crossings of gas mains with regard for possible defects of the pipe metal. Using the “3D PipeMaster” software complex, we compute different versions and present recommendations concerning the optimal location of pipe-laying machines with an aim of realization of the possibility of lifting the pipe to a height required for repair works with guaranteed validity of the prescribed conditions of strength. The values of tractive forces in the pipe-laying machines are determined. The optimal sites of fixing the pipeline in the transverse direction are indicated and the corresponding forces acting in the cables used to prevent the transverse motions of the pipeline are calculated. [ABSTRACT FROM AUTHOR]

An analytical method is proposed for the solution of geometrically nonlinear Brazier problem for thin-mall pipes with initial cross-sectional shape imperfection in the case of action of pressure. Geometrical equations relating displacement components to strains and equilibrium equations taking into account change in the curvature of pipe cross section and axis have been derived. A solution in a first approximation for dimensionless flexibility parameter is presented, the exactness of which is illustrated by numerous examples. For the case of joint action of external bending moment and pressure, a limit curve of the critical moment value as a function of pressure value has been obtained. [ABSTRACT FROM AUTHOR]

The notion of the dynamic flexibility factor of a pipe bend to be used in problems on the calculation of harmonic vibrations of pipelines is formulated. Based on the Vlasov semi-momentless theory, simplifying hypotheses are introduced that make it possible to reduce the problem statement to the solution of the quartic differential equation. Using the results of the dynamic analysis for toroidal shells, the procedure for taking into account the increased flexibility of pipe bends under dynamic loading has been developed. The expression for the flexibility factor is derived as a function of both the geometrical parameters of the bend and the vibration frequency. The efficiency of the derived expression for the flexibility factor is illustrated by a great number of examples. [ABSTRACT FROM AUTHOR]

Dynamic behavior of piping as a beam system has been analyzed with the use of the dynamic stiffness method. According to this method, the equations describing the relation between unknown parameters are written by the method of initial parameters, therefore, the solution procedure is similar to that for a static problem. It is shown that for curvilinear beams it is simpler and more efficient to apply a model that consists of straight segments and inertia-free rotation elements. To determine natural frequencies of 3D beam systems, it is proposed to use a method of disconnection of displacements, which makes it possible to discern the frequencies corresponding to different vibration modes (transverse, longitudinal, etc.). The approach allows a correct simulation of the system behavior under forced vibrations induced by a harmonic exciting force. [ABSTRACT FROM AUTHOR]

A new analytical method is proposed for the analysis of boundary effect in a pipe bend portion loaded by bending moment combined with internal pressure. The proposed method is based on the simplifying hypotheses, which make possible to represent all deformation- and force-related parameters in terms of the tangential displacement assumed in the form of the Fourier series expansion by the circumferential coordinate. A set of quadric differential equations by axial coordinate containing unknown displacement expansion coefficients is derived. We obtained an analytical approximate solution for a pipe bend portion and precise solution for a straight pipe, which are expressed via Krylov functions. We formulate the application procedure for the method of initial parameter, where the values of tangential and longitudinal displacements, axial and tangential forces are used as boundary conditions. We present the equations relating the above-mentioned parameters in the initial and end sections of the pipe bend portion. The results obtained are compared with the available published data. [ABSTRACT FROM AUTHOR]

A problem of deformation of a curved shell loaded by internal pressure, axial force, and temperature difference is discussed. Physical equations are derived whereby the displacements and angles of rotation of the line of centers of mass of cross sections of a shell are related to loading parameters. A general constitutive set of equations for a curved element during its deformation is given. Using a method of initial parameters, an analytical solution is obtained for the differential equations for displacements and angles of rotation of the center line allowing for the action of distributed forces and moments. [ABSTRACT FROM AUTHOR]

We analyze a problem of determination of stressed state and flexibility of a pipe bend under a combined action of internal pressure and bending moments applied both in and out of plane of the bend curvature. This problem is referred to as a geometrically nonlinear one where an increase in internal pressure brings about a decrease in ovalization stresses induced by bending moments. A unique method of allowing for the pressure is put forward, which is based on the consideration that the pressure-induced circumferential stresses greatly exceed the stresses due to bending moments. A general set of equations for all displacements and stress components is derived. The present results are compared with those reported elsewhere. [ABSTRACT FROM AUTHOR]

A new method for analysis of stress-strain state in elastic cylindrical toroidal shells is put forward, whereby forces and displacements are chosen as unknown junctions. The method enables a study of the bend ovalization phenomenon that occurs when three-dimensional bending moments are applied. The authors have derived geometrical equations relating displacement components and strains, and introduced smallness hypothesis, which makes it possible to neglect some combinations of displacements during the shell deformation analysis. The Karman hypothesis of nondeformability of a pipe median surface is demonstrated to be applicable only after the circumferential force is excluded from equilibrium equations. The authors have established the limits of applicability of the solutions obtained, depending on the order of approximation of the flexibility parameter. Beam differential equations have been derived for a curvilinear bar, which relate angles of rotation and center-line displacements with applied loading factors. The results obtained are compared to those reported elsewhere. [ABSTRACT FROM AUTHOR]

The paper describes a method and main results of a refined stress-strain state evaluation for a welded joint of the hot collector to steam generator nozzle of a nuclear power plant with a WWÉR-1000 reactor, which takes into account a fuller range of the actual loading conditions in operation. In calculations, we considered the stresses induced by uncompensated thermal expansion of the reactor elements. The results of 3D finite element calculations suggest that the level of local stresses in the area of the joint exceeds the metal yield stress. The calculated stresses for the outer nozzle surface agree satisfactorily with the in-situ strain measurement data. [ABSTRACT FROM AUTHOR]

The authors consider edge effects in buried pipelines that occur in the region of joining of a straight buried pipe and a bent insert (factory bend, elbow, or an elastically bent segment). The action of those effects results in the appearance of additional bending moments, which are proportional to the difference between the axial force in an infinite straight pipeline and that in a closed-end pipe, and depend on the geometrical parameters of the pipeline and physical-mechanical characteristics of the soil. Specific examples of analysis of elastic interaction of a pipeline with the soil for pipe bends with various radii of the bend arc are offered. It is shown that additional bending stresses may exceed appreciably the stresses from the axial force, and therefore, they should be taken into account when designing and building pipelines. The solution for an elastically bent segment has been obtained and analyzed. [ABSTRACT FROM AUTHOR]

Activities of succinate dehydrogenase (SDH) and α-glycerophosphate dehydrogenase (hyaloplasmic and mitochondrial: α-GPDHH and α-GPDHM) in peripheral blood lymphocytes, and the response of SDH activity to exogenous epinephrine in vitro (the epinephrine test) were studied in 20 healthy subjects and 46 patients with hypertensive neurocirculatory dystonia. Activities of SDH, α-GPDHH, and α-GPDHM in blood lymphocytes and SDH adrenoreactivity in epinephrine test were higher in patients than in healthy controls. Treatment with hypotensive agents (isradipin and pyrroxan) moderated adrenoreactivity. Phytotherapy normalized the baseline activities of succinate oxidase system and α-glycerophosphate pathway in blood lymphocytes. [ABSTRACT FROM AUTHOR]

Gelation in concentrated solutions of high-basicity aluminum hydroxychloride in the presence of inorganic salts was studied. Comparative evaluation of the coagulation activities of aluminum hydroxychloride and solid formulations on its base in water purification was made. [ABSTRACT FROM AUTHOR]

Heat-insulating ceramic materials have been developed, whose porous structure is provided by foaming and gas formation. Foaming and gas-forming agents, stabilizing, plastifying, and other additives and fixing agents for foam and gas mixtures are identified. [ABSTRACT FROM AUTHOR]

We propose a method for the analysis of stable crack-length increment Δ a (where Δ a is regarded as a function depending on the parameters KI and σ r of the two-criterion approach). It is shown that the K Rcurve consists of two portions: {K′} R and {K′ ′} R curves, which in the framework of the fracture evaluation diagram correspond to two portions of the loading curve – prior to and after its intersection with the limit curve of the fracture evaluation diagram. We propose an analytic description of the {K′} R curve as the first approximation, while the shape of the {K′ ′} R curve is shown to be fully determined by the limit curve of the fracture evaluation diagram. The method has been verified by using the experimental data of the ASTM Round Robin tests performed in 1979–1980 and predicting the maximum fracture load P f of cracked specimens made of various materials: compact specimens, center-cracked specimens and special specimens with three holes. Good agreement between predicted and experimental data is demonstrated. [ABSTRACT FROM AUTHOR]

Heat exchange of dynamic (mixing) beds of powders with heat-transfer surfaces in a tube with a helical conveyer and in a rotating smooth horizontal cylinder is studied by experimental methods. The heat-transfer coefficients as functions of the regime of powder motion are obtained. [ABSTRACT FROM AUTHOR]

The newly devised model makes it possible to determine the heat treatment regimes of alloys of the system Cu−Al−Mn with similar temperature manifestations of ESM, with the attainment of the maximal thermomechanical characteristics possible for each group of alloys. As a result of heat treatment in the optimal regimes, ternary intermetallic compounds segregate in the structure of these alloys, and they improve the parameters of the ESM. Consequently, for widespread use in engineering we recommend alloys of the system Cu−Al−Mn which are distinguished from the known alloys with the ESM (based on titanium nickelide) by the accessibility of the initial materials and simpler production technology. [ABSTRACT FROM AUTHOR]

It is shown that spent vanadium catalysts can be used to obtain fritted colored glazes. The technological parameters for the synthesis of glaze glasses in the borosilicate system using spent vanadium catalysts are investigated, and the physical–chemical parameters of the glazes are determined. Decorative glazes with straw-color, brown, and gray tones and lustrous, mat, and semi-mat finishes have been obtained. [ABSTRACT FROM AUTHOR]

The regioselectivity of S-alkylation of SH-substituted purine bases with glycidol tends to grow with decreasing temperature. A procedure was developed for epoxidation of these compounds in wet liquid ammonia. The products were tested for immunostimulating activity. [ABSTRACT FROM AUTHOR]

Via direct oxidative addition of 1,1-dichloroethylene to adamantane or 1,3-dimethyladamantane one obtains diethanoic acids of the adamantane series, which are useful in themselves or for preparation of other functional derivatives. Optimal reaction conditions were found by mathematical modeling. [ABSTRACT FROM AUTHOR]

The optimum conditions were found for obtaining the polyester from the acid chloride of 1,3-adamantanedicarboxylic acid and phenolphthalein. [ABSTRACT FROM AUTHOR]

A letter to the editor concerning the reaction of guanine with glycidol is presented.

The dependence of the absorption coefficient of 935-nm radiation on the water content of intact leaves of various plants is investigated. A linear increase of the absorption coefficient with increasing thickness of leaves due to an increase of their water content is established. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article about synthesis of purin nucleosides containing glucose residues published in the February 9, 2005 issue.

In the manufacture of lightweight by the semidry pressing method using thermoanthracite as the combustible addition, it is possible to obtain goods corresponding to GOST 5040-58. The firing time is 144 h. The firing should be carried out in an oxidizing atmosphere with a ten-course setting in separate chambers with a special schedule. It is necessary to carry out further work to find whether it is possible to reduce the firing time in the low-temperature interval by selecting the appropriate draft schedule. [ABSTRACT FROM AUTHOR]