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The present paper is devoted to the development of the method for searching an approximate solution of non-stationary problems on a variable interval. This method was first proposed by L.I. Slepyan. Here, the field of its applicability has been expanded to systems of equations, including equations of both hyperbolic and parabolic type. We describe the procedure of such approach in detail on a number of classical partial differential equations and compare the obtained results with exact analytical solution. Also, we consider a dynamic non-coupled thermoelastic problem. The method of expansion on a variable interval allows us to estimate the material response to a thermal disturbance at a large distance from the source.

The problem of a heating source acting on a certain part of a beam surface and moving along it with given speed is solved. It is shown that the most significant role in formation of the beam deflection under loading by a compression force is played by concentrated moments occurring at the moving boundary of the heating source. It is noted that for a source speed less than some critical value, the beam deflection is essentially nonmonotonic. In this case, the largest beam bending deflection occurs when the source speed reaches a value corresponding to the Euler critical force.

Within the framework of the one-temperature model of thermoelasticity, the analysis of the effect of electon localization processes on the thermoelastic response of conductors under pulsed laser irradiation is performed. It is shown that the localization of electrons can lead to a significant tightening of the deformation processes in conductors compared with the processes that develop according to the usual thermoelastic mechanism.

Within the framework of a one-temperature model of thermoelasticity, an analysis of the effect of electron localization processes on the thermoelastic response of conductors under pulsed-laser action is conducted. It is shown that electron localization can lead to considerable tightening of the deformation processes in conductors as compared with processes that develop in accordance with a typical thermoelastic mechanism.

The problem of a heating source acting on a certain part of a beam surface and moving along it with given speed $${v}$$ is solved. It is shown that the most significant role in formation of the beam deflection under loading by a compression force is played by concentrated moments occurring at the moving boundary of the heating source. It is noted that for a source speed less than some critical value, the beam deflection is essentially nonmonotonic. In this case, the largest beam bending deflection occurs when the source speed reaches a value corresponding to the Euler critical force.

We considered a rectilinear crack in a thin elastic plate in this work. Stretching the plate in the direction perpendicular to the crack, compressive stresses appear in the vicinity of the crack, which lead to stability loss in the plain form of plate equilibrium at a certain tension level. This study is aimed at clarifying whether the stability loss contributes to crack growth or leads to deformation stabilization. The stress state of the plate in the initial post-critical stage is studied. An approximate analytical solution is proposed. The finite element method is used for solving the problem of stretching a plate after stability loss. The effect of the loss of a plain deformation form when a plate with a central crack is stretched to the level of the stress state in the vicinity of the crack tip is estimated. An analysis of the stressed state in the vicinity of the tip of the central crack under uniaxial tension suggests that, at possible local buckling near the crack, there is an increase in stretching stresses in the vicinity of the crack tip and so the load leading to fracture decreases.

Study of various wound healing methods is a relevant issue of modern veterinary medicine. One of the investigated methods of wound healing is moist wound healing in a hydrated environment using hydrogel patches. In described clinical case, an eight-year-old female American Pit Bull Terrier was subjected to mast cell tumor surgical removal on the left hindlimb. During the patient postoperative treatment, Sorbalgon®, Hydrocoll® and HydroClean® dressings were used to protect the surgical site and maintain high moist environment in the wound. The dressings absorbed wound exudate and stimulated both the surgical site cleansing and the granulation tissue formation, made it possible to heal large wound on the limb without the keloid scar development.

Antimicrobial resistance formation in various bacteria is a serious biosafety threat. In this regard, the important issue in medical and veterinary fields is not only the rational use of antibacterial drugs, but also the search for ways to significantly reduce the need for antibiotics. Three studies designed to research into these challenges are described. The results indicated that (1) the bacteriuria presences in 62.4 +/-4.1% of urine samples obtained from companion animals (the microflora count in urine samples is estimated from ’++’ to ’Entire Field-of-View’); (2) 16.3 +/-4.0% of samples from companion animals showed bacteria with low antibiotics sensitivity, and 8.1 +/-3.0% of samples contained bacteria resistant to 30 antibiotics included in the susceptibility test; (3) the Bovhyaluronidaze azoximer reduce antimicrobial therapy duration statistically significant (p=0.0089). The studies were conducted at the facilities of St. Petersburg State University of Veterinary Medicine and Bars veterinary clinic chain in St. Petersburg, Russia. A randomized clinical trial of Bovhyaluronidaze azoximer effect on course of disease and treatment duration of acute and chronic prostatitis and urocystitis, including complicated by urolithiasis, was conducted in 54 dogs. Animals were randomly assigned to intervention (n=34) and control (n=20) groups. Animals of both groups received the antimicrobial therapy. Interventional group patients additionally received Bovhyaluronidaze azoximer in the form of rectal suppositories. The antimicrobial therapy mean duration in intervention group animals took 14.88 +/-4.98 days, in control group animals — 18.65 +/-5.40 days. The study findings imply that bacteriuria is widely prevalent in companion animals and antimicrobial resistance is increasing issue in veterinary medicine. Bovhyaluronidaze azoximer contributes to microcirculation restore and increases the bioavailability of antibacterial drugs at the site of infection. This makes its relevant for use in the complex treatment for septic and inflammatory processes. This allows to reduce the antimicrobial course duration (and completely decline antibiotic therapy in some cases) and prevent the formation of chronic inflammation and infection sites.

A two-component model which accounts for electron gas pressure is proposed for describing the dynamics of thermoelastic and thermoacoustics effects in laser-irradiated conductors. The model medium represents two interpenetrating continua such that interacting particles of both exist at each point of the medium. The electron gas in the model comprises free and bound electrons of which the former obey the laws for perfect metals and the latter obey those that account for electron trapping to localized levels and for electron transitions from level to level, i.e., for jump diffusion and hopping conductivity. Unlike the classical model of thermoelasticity, the proposed model is the first to show that the electron gas pressure depends strongly on the temperature difference between the electron gas and the conductor lattice and on the change in the density of free electrons as localized species become free by the Mott mechanism. The duration of acoustic pulses in the conductor lattice is essentially dependent on the time of laser irradiation and on how long the gas and the lattice differ in temperature, with the longest acoustic pulse falling on a certain localized electron density. The model data are compared with experiments.

Metal–matrix composites based on an aluminum matrix reinforced with ceramic particles are widely used as structural materials in the aerospace and automotive industries. The main problems in the manufacture are the uniformity of the distribution of particles over the volume, poor adhesion of ceramic particles to the matrix metal, and the formation of aluminum carbide at the interfaces, leading to undesirable embrittlement. We propose a new technique for the manufacture of metal–matrix composites, which consists in creating a composite material, when carbide nanostructures form a framework in the volume of an aluminum matrix, and which allows solving the above problems. A finite element model of deformation of a metal–matrix composite reinforced with carbide structures is constructed.

Numerous experimental studies on shock wave loading of metals have shown by electron microscopy that the crystal structure of the material can undergo transformation in a certain impactor velocity range. At the macroscale, these changes are observed as energy losses associated with the formation of a new structure. The losses are manifested on the time-velocity profile of the rear target surface which contains key information about the material properties. In this paper, a two-component model of a material with a nonlinear internal interaction force is proposed for the description of structural transformations, taking into account the periodic structure of the material. Dynamic equations are written with respect to the motion of the center of mass of the components acting as a measured macroparameter, as well as with respect to their relative displacement serving as the internal degree of freedom responsible for structural transformations. The proposed model is applied to solve a quasi-static problem of the kinematic extension of a two-component rod in order to determine the parameters of a nonmonotonic stressstrain curve, which is often used in describing materials subjected to phase transformations. By solving a dynamic problem of nonstationary impact on the material by a short rectangular pulse, the effect of nonstationary wave damping is demonstrated which is associated with the wave energy dissipation in structural changes of the material. An analytical expression is obtained on the basis of a continuous-discrete analogy for estimating the duration of structural transformations and the parameter characterizing the internal interaction force between the components. The conclusions are confirmed by a numerical solution of a nonlinear Cauchy problem within the finite difference framework.

The paper considers a new 3D nanostructuring technology of next-genergtion ceramic composites based on a ceramic matrix reinforced with titanium nitride (TiN) gnd silicon carbide (diC). Research data are reported on the formation of TiN and diC nanostructures on the surface of disperse alumina during successive gas chemisorption of organic Ti(N(CH3)2)4 (tetrakis-dimethylamino-titanium, TDMAT) and ammonia NH3 in the first case and Cl2Si(CH3)2 and methane CH4 in the second. Such chemisorption increases the number of surface-attached Ti-N groups crystallized on annealing at 1100°C with the formation of a TiN or a SiC nanoparticle layer. According to X-ray diffraction and electron microscopy, TiN nanoparticles with an average size of about 40 nm are formed on the surface of alumina particles after TDMAT and NH3 treatment for 2 h and subsequent annealing at 1100°C. The mechanical properties of compacted α-A12O3-based ceramics reinforced with TiN and SiC nanoparticles excel the properties of the best ceramic materials provided by different manufacturers.

A model of material of complex crystalline structure consisting of two lattices coupled by nonlinear interaction forces that ensure several stable equilibrium configurations is considered. The continuum model is compared with the discrete model whose analysis reveals the effect, which has been observed in high-speed deformation experiments, of decrease in the initial pulse under nonstationary actions.

Loss of stability under uniaxial tension in an infinite plate with a circular inclusion made of another material is analyzed. The influence exerted by the elastic modulus of the inclusion on the critical load is examined. The minimum eigenvalue corresponding to the first critical load is found by applying the variational principle. The computations are performed in Maple and are compared with results obtained with the finite element method in ANSYS 13.1. The computations show that the instability modes are different when the inclusion is softer than the plate and when the inclusion is stiffer than the plate. As the Young’s modulus of the inclusion approaches that of the plate, the critical load increases substantially. When these moduli coincide, stability loss is not possible.

The features of the porous nickel surface preparation for conducting the chemical processes of nanostructuring the dispersed phase TiC on the nickel surface were studied.

Increasing the number of dogs and cats kept in urban households makes relevant research of new effective methods of treatment of companion animals. We conducted studies of the effect of Bovhyaluronidaze azoximer on the treatment duration of suppurative wounds. The study was carried out on 42 animals (24 cats and 18 dogs) with septic processes in two groups. The animals of the both groups were given conventional therapy; in animals of the experimental group the Bovhyaluronidaze azoximer preparation was additionally included as a part of a complex therapy. The effect of the use Bovhyaluronidaze azoximer preparation was evaluated by three indicators: the wound cleansing from purulonecrotic masses duration, the duration of existence of edema, the number of managements of wound. The median wound cleansing time in the experimental group improve on 2.29 days. The median duration of existence of edema in the experimental group was in less time on 1.57 days in comparison with the control group. The median number of required managements of wound is reduced by 5.00 manipulations in the experimental group in comparison with the control group. The results of our study show that Bovhyaluronidaze azoximer can be recommended for use in the therapy of suppurative wounds.

The deformation and fracture of graphene sheets containing 555–777 defects have been investigated by molecular dynamics simulations. Each such defect is a divacancy forming a localized configuration of three pentagonal and three septangular cells of carbon atoms in a hexagonal graphene lattice. An emphasis is made on the influence of 555–777 defects in graphene on its mechanical characteristics (stress–strain curve, uniaxial tensile strength, and maximum elastic strain).

The deformation and fracture processes in graphene nanoribbons containing linear quadrupoles of disclinations are investigated by the method of molecular dynamics. Special attention is given to estimating the effect of the curvature formed by disclinations and free boundaries in graphene nanoribbons with linear quadrupoles of disclinations on their mechanical characteristics (the stress–strain curve, the strength at the single-axis tension, and the degree of plastic deformation).

In the present paper a new model for describing structural transformation of solids under external impact is discussed. We suppose that the material consists of two crystalline lattices with close physical properties, connected by nonlinear interaction force. The relative displacement of the components is considered to be an additional degree of freedom responsible for transition of material to a new equilibrium position. Using experimental data on shock-wave loading and analogy between continuous model and its discrete representation allows to evaluate the unknown parameters and to reveal the mechanism of energy transfer from macro to micro level. Also it becomes possible to predict the parameters of external impact, necessary to start the process of transition to another state. The results of analytical investigation are confirmed by numerical solution of the original problem.

Some problems of strength and stability of thin constructions with defects and inclusions, which are of vital importance for nano- and microtechnology, are investigated. The attention is paid to the estimation of the number of defects influencing the capacity for work of nanosized plated and shells. The influence of surface effect is taken into account.

Alumina micro- and nanopowders with the particle size from 200 μm to 40 nm synthesized by the sol-gel method are studied. The particle size dependence of γ-Al2O3→α-Al2O3 phase transformation is studied by differential thermal analysis, X-ray diffraction method, and transmission electron microscopy. X-ray diffraction data show that for alumina nanoparticles γ-Al2O3→θ-Al2O3 phase transformation occurs at 900°C, and for micro-particles it occurs in the temperature range 1150–1200°C. The alumina ceramics produced of alumina nanoparticles is shown to have higher flexural strength under three-point bending than the ceramics produced of micro-particles. The obtained results demonstrate that alumina particle size reduction stabilizes the formation of α-Al2O3 at lower temperatures, due to which the grain growth rate decreases and the flexural strength of monolithic oxide ceramics increases.

This paper deals with the problem of local buckling caused by uniaxial stretching of an infinite plate with a circular hole or with circular inclusion made of another material. As the Young’s modulus of the inclusion approaches that of the plate, the critical load increases substantially. When these moduli coincide, stability loss is not possible. This paper also shows the difference between them when the inclusion is softer than the plate and when the inclusion is stiffer than the plate. Computational models show that instability modes are different both when the inclusion is softer than the plate and when the inclusion is stiffer than the plate. The case when plate and inclusion have the same modulus of elasticity, but different Poisson’s ratio is investigated too. It is also discussed here the case when a plate with inclusion is under biaxial tension. For each ratio of the modulus of elasticity of plate versus inclusion it’s obtained the range of the load parameters for which the loss of stability is impossible.

The present paper is devoted to a two-component model of material with nonlinear interaction force, which describes the dynamics of crystalline lattice transformation under shock-wave loading. The governing equations are written for the center of mass displacement and relevant displacement of the components, which is considered to be an internal degree of freedom, responsible for structural transformations. Basing on the analogy between the continuum equations and the corresponding discrete model, we carry out the investigation of the quenching of a non-stationary wave due to the dissipation of energy into structural conversions and estimate the duration of this process. The obtained analytical results are confirmed by the numeric calculations performed by finite difference method.

Agriculture modernization is a topical issue for both the global and domestic economy. Intensification of livestock farming results in an increased production of manure. Recycling of manure into bedding is one of the modern utilization technologies. National regulations do not specify requirements for currently applied bedding types, including manure-based bedding. The foreign experience, however, demonstrates several economic, zootechnical and hygienic advantages of this material. The field veterinary study revealed the positive health effect of bedding. The cows housed without bedding featured threefold higher risk of surgical diseases of limbs. Technical and economic assessment of a dairy farm with 1000 dairy cows showed the following annual operating costs when the major part of manure was passively composted and a part of manure was recycled into the bedding by (1) aerobic solid-state fermentation in a chamber fermenter and finish drying in a dryer drum – 24.2 million roubles; (2) aerobic solid-state fermentation in a drum fermenter – 21.7 million roubles; and (3) thermal drying in a dryer drum – 27.5 million roubles. At the same time, if all manure produced was composted and the bedding was purchased from external sources, the costs would be 27.9 to 35.2 million roubles depending on the bedding material.

The degradation of the surface and structure of single-crystal tungsten and sintered powder tungsten during the action of a pulsed plasma jet is studied. It is shown that the degradation of a tungsten target during the action of a plasma jet with an energy flux density of 0.25–1 MJ/m2 is accompanied by surface evaporation and melting and the fracture of surface layers on scales of 150–250 μm. The results of a numerical simulation of the thermomechanical processes that occur in a tungsten target during the action of a plasma jet are presented. The degradation of tungsten during the action of a plasma jet is shown to proceed almost continuously from the action (evaporation, melting) to the times that are more than three orders of magnitude longer than the action time, which is caused by the thermomechanical processes occurring in the tungsten target. Moreover, the action of thermal stresses leads to structural and morphological changes throughout the sample volume, and these changes are accompanied by recrystallization in adiabatic shear bands.

The conditions for possible reduction of hydrodynamic resistance by the compliant coatings are considered from two points of view: pulling the laminar flow and alteration of turbulence generation in the near-wall zone. A strong effect of the longitudinal pressure gradient and reasonability of the search for the laminarized bypass flows in the presence of compliant coatings are distinguished.

In the process of deformation of such multilayer structures, significant stresses can arise on the foundation-coating interface because of the difference in their physical and mechanical properties, which can result in fracture or coating separation. The action of static or impact loads on damage onset and development in the adhesive layer in such multilayer structures has been investigated almost completely, but similar processes in the case of suddenly applied vibration loads have not been studied to a large extent. The latter draw attention because of the fact that even small variable actions can localize vibrations near the imperfections (inclusions, defects, etc.) and can be accompanied with an increase in the damage of the adhesion layer, which results in partial separation of the film. In the present paper, the possibility of vibration localization in damaged regions and the influence of the localization on the damage development till the film separation are studied. The first of the possible scenarios of the damage region behavior is its monotone increase. The second scenario of damage behavior is its constant stepwise growth. In this case, damage increases on some time intervals and is constant between the intervals. Under the conditions obtained in the paper, this second scenario can be transformed into the first one. The third scenario is that damage does not increase. This scenario can be realized under sufficiently large vibration load frequencies. Some conditions under which damage behavior is determined by the localized oscillating part of the solution are derived.

The influence of localization of vibrations on film exfoliation from an elastic basis is investigated. A model is suggested that makes it possible to find an approximate analytical solution and to analyze the conditions of increasing and decreasing exfoliation.

In modern constructions, thin-layer coats are often used as protecting or strengthening elements. Deformations of such constructions may cause significant stresses on the interface between the base and the coat because of the difference in their physical-mechanical properties, which leads to the destruction or detachment of the cover. Of special interest is strength analysis under dynamical or vibrational impacts because of the possibility of localizing oscillations in a neighborhood of the initial inhomogeneities (such as inclusions, defects, construction elements, etc.).

The main principles and methods of developing the single-layer monolithic compliant coatings for turbulent drag reduction are presented.

An improved method to measure the dynamic viscoelastic properties of elastomers is proposed. The method is based on the analysis of forced oscillation of a cylindrical sample loaded with an inertial mass. No special equipment or instrumentation other than the ordinary vibration measurement apparatus is required. Upper and lower surfaces of the viscoelastic material sample were bonded to a load disc and a rigid base plate, respectively. The rigid base plate was subject to forced oscillations driven by a vibration exciter. Two accelerometers were attached to monitor the displacement of the base plate and the load disc. The recorded magnitude ratio and the phase difference between the load disc and the base plate vibrations represent the axial, dynamic deformation of the sample. The data are sufficient to obtain the dynamic properties of the sample, oscillation properties of vibration exciter, whereas the sensitivity of gauges having no effect on the calculation results. For accurate calculation of the properties, a two-dimensional numerical model of cylindrical sample deformation was used. Therefore, a form factor, which takes into account the sample sizes in one-dimensional models, is not required in this method. Typical measurement of the viscoelastic properties of a silicone rubber Silastic® S2 were measured over the frequency range from 10 Hz to 3 kHz under deformations (ratio of vibration magnitude to sample thickness) from 10−4% to 5%. It was shown that the modulus of elasticity and the loss tangent fall on a single curve when the ratio of load mass to sample mass changed from 1 to 20. When the sample diameter was varied from 8 to 40 mm, the modulus of elasticity fall on the same curve, but the loss tangent curves showed some degree of scatter. Studied temperature dependence and nonlinear behavior of viscoelastic properties is found not to be associated with this effect.

Hydrogen embrittlement of materials is one of the important factors for an estimation of serviceability of designs. In spite of the fact that many works are devoted to research of hydrogen influence on properties of metals and alloys, there are enough “white” spots in this problem, in particular, the influence of kinetic processes inside a material, giving rise to hydrogen redistribution, on the basic strength characteristics at static and dynamic loading. The absence of an authentic mechanical model, whose description is based on the basic fundamental principles of rational mechanics, makes the problem rather actual, since, inherently, the presence of such a model would allow to describe the influence of internal kinetics on the macroparameters of a material, which is today extremely important in view of the huge amount of hypotheses which are ready to confirm only special experiments and do not allow to use them in other cases. The present work offers a model based on experimental data on the decrease in break energy of internuclear bonds at landing particles of hydrogen, i.e., the decrease in a level of the free energy. The offered model allows to explain the localization of hydrogen in the field of the increased concentration of stresses and change of material properties.

We suggest a two-component model of a material experiencing structural transformations and use it to study how dynamic and evolution processes affect these transformations. We note that an essential role is played by internal interactions caused by internal forces arising between the components as well as by exchange processes describing variations in the composition of both components. We illustrate the model by specific examples.

A new method for measurement of viscoelastic properties of materials, based on the exact solution of the problem of the forced oscillations of a flat sample loaded by inertial mass, is proposed. The device for these measurements is described. The elasticity modulus and loss tangent are measured within the frequency range from 100 Hz to 10 kHz at relative deformation of a sample below 1%. The approximate formulas for calculation of viscoelastic properties are derived, and the conditions of their applicability are determined. The methods for expansion of the frequency range and measurement of materials with extremely high loss tangent are proposed. The proposed method is compared with the current Standard. It is shown that the new method has the higher accuracy and expanded range of parameter measurements, and the construction of device is easy and reliable, since it does not require the knowledge on the oscillation properties of vibration source.

Over the past forty years intensive investigations into the use of compliant surfaces have been undertaken, both theoretically and experimentally, in order to obtain turbulent drag reduction in boundary–layer flows. Although positive results were found in some of the studies, none of these had been successfully validated by independent researchers. In this paper the results are reported of a recent investigation carried out by the authors to verify the experimental results of Semenov in 1991 and Kulik and co–workers in 1991, who successfully demonstrated the ability of compliant surfaces to reduce the skin–friction drag and surface–flow noise in a turbulent boundary layer. A strain–gauge force balance was used in the present study to directly measure the turbulent skin–friction drag of a slender body of revolution in a water tunnel. Changes in the structure of turbulent boundary layer over a compliant surface in comparison with that over a rigid surface were also examined. The results clearly demonstrate that the turbulent skin friction is reduced for one of the two compliant coatings tested, indicating a drag reduction of up to 7 per cent within the entire speed range of the tests. The intensities of skin–friction and wall–pressure fluctuations measured immediately downstream from the compliant coating show reductions in the intensities of up to 7 and 19 per cent, respectively. The results also indicate reductions in turbulence intensity by up to 5 per cent across almost the entire boundary layer. Furthermore, an upwards shift of the logarithmic velocity profile is also evident indicating that the thickness of the viscous sublayer is increased as a result of turbulent drag reduction due to the compliant coating. It is considered that the results of the present experimental investigation convincingly demonstrate for the first time since the earlier work in Russia (by Semenov and Kulik) that a compliant surface can indeed produce turbulent drag reduction in boundary–layer flows.

Methods and results of the investigation of pulsed pressures excited in the bulk of a quartz glass by focused nanosecond laser pulses (λ=1.06 μm, τ0.5≈12.5 ns) are described. The experiments were performed in a wide range of laser power densities, which allowed the generation of pulsed pressures to be studied for both thermomechanical effect and optical damage in the bulk of glass. We have measured displacement of the free sample surface (laser interferometry), determined optical damage thresholds, and performed fractographic analysis of the fracture zones. The results revealed nonlinear thermomechanical response and allowed us to estimate the change in the optical absorption and temperature of the material near the optical damage threshold. Quantitative data are obtained on the relative efficiency of pulsed pressure production during the thermomechanical effect and optical damage. Data on the dynamic strength of a quartz glass are obtained for the first time in the absence of a damaged surface layer. Using the proposed method, it is possible to determine the energy consumption for the fracture of brittle materials. High sensitivity of the method of laser-induced breakdown allows this technique to be used for studying the influence of microstructure on the mechanical and optical properties of transparent media.

In the present paper, we propose new equations describing the fluid behavior in nanochannels with its molecular structure. We consider the Poiseuille flow and the flow throw the channel with vibrating walls. The obtained results show that it is possible to describe the structural transformations in thin layers by using the continuum mechanics methods. We introduce new degrees of freedom of the material by introducing the second continuum, which plays the role of the arising new phase of state. In the models considered here, the properties of the new phase are determined by the influence of rigid boundaries with a different structure.

The paper presents results of development of the novel shrinkage-free, adaptable to machining and easily welded alumo-boron-carbide silicon materials that experience the cermet stage during their manufacturing. A specific feature of the like ceramics is their double-stage sintering process when, after the original stage, a metal-ceramic blank has a sufficient strength and is easily machined by conventional metal-cutting tools. In addition, such materials are electrically conductive, therefore, the elasto-erosion treatment technique can be applied. Subsequently, a machined part is finally sintered, whereas all the geometries remain actually unchanged due to the shrinkage absence. Prior to the final sintering, all separate parts can be joined by the diffusion welding with the seam strength being 5–10% different from the strength of the main part. The paper provides an insight into the processes and results of tests of the representative selections of samples of four types of the structural ceramics that are experiencing the cermet stage during the process of their formation. Also, ceramic parts for the CGTE hot passage are demonstrated.Copyright © 2008 by ASME

Optimal dose regimen for radon treatment in different diseases should be estimated with dose-effect curve in the range of a stimulating action of moderate doses. The range of therapeutic doses is situated on the ascending part of the resultant curve between minimal and maximal levels of the factor effect.