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The paper presents the results of scanning of mechanical properties of coniferous (common pine Pinus sylvestris) and deciduous (small-leaved lime Tiliacordata and common oak Quercus robur) trees wood using nanoindentation on crosscut face. Manifold increase in microhardness H and Young's modulus E has been observed between early and late wood in every annual growth ring. Significant differences in intraring radial dependencies of H and E have been found among studied species. For all studied species the average values of E and H of early wood in each annual ring are found to be independent from ring width, while such dependence for late wood is weak at most. The ring widths measured by nanoindentation coincide with the ones measured by standard optical method within 2–3%. The developed technique and obtained results can be useful (1) to amend the understanding the origins of macromechanical properties of various wood species and their dependence upon microstructural characteristics and growth conditions, (2) to optimize the technologies of growing, reinforcement and subsequent usage of the wood, (3) to develop new independent high resolution methods in dendrochronology. [ABSTRACT FROM AUTHOR]

Thermal diffusivity a and thermal conductivity λ are important parameters for many structural and functional material applications. These parameters determine the intensity of heat transfer, the quality of thermal insulation, the rate of heating/cooling, the efficiency of power equipment, as well as the possibility of reaching a stationary mode. In laser technologies, a and λ define the radiation resistance of the optical components of a system. In laser technologies involving material removal, these parameters determine the speed and quality of machining. At present, the majority of methods for measuring a and λ in solid materials require cutting out samples of a certain geometry, which makes such methods unsuitable for testing finished products. In this paper, we propose an express method for determining a and λ in translucent materials, which does not require cutting samples out of an object under inspection. This method implies registration and analysis of a nonstationary temperature field on the surface of a test object using a high-speed thermal imaging camera. An unsteady heating spot is created by a focused laser beam. The laser is operated in the mode of intermittent switching and continuous irradiation under constant intensity during the entire period of measurements. The heat propagated from this spot to the periphery forms a nonstationary temperature field, which contains information about a and λ. The a value is derived from the primary data using original algorithms and software. The dynamic temperature field is recorded by a thermal camera, a noncontact and high-speed device capable of processing a large amount of information (each of the many hundreds of thousands of pixels of a professional thermal imager matrix is a temperature sensor in a small surface area). The specifics of measuring thermal diffusivity a and thermal conductivity λ in translucent materials of laser beam optics is noted. Thus, the low radiation absorption coefficient and the possible curvature of the surface (for example, in lenses) require special measures. Due to the large amount of information contained in the dynamic patterns of thermal field and the possibility of averaging over a large data array, the RMS of the thermal diffusivity measurement does not exceed 2%. [ABSTRACT FROM AUTHOR]

The thermophysical characteristics of nonmetallic materials (in particular, thermal conductivity and thermal diff usivity) account for their heat-insulating properties, the quality of processing in various laser technologies, and also signifi cantly aff ect the optical strength of power optics materials. Determination of thermophysical characteristics by traditional methods requires laborious manufacturing of specimens of certain sizes and two-sided access to them, which prevents the use of nondestructive testing of large workpieces and fi nished products. The article describes a nondestructive thermographic method of measuring the thermal diff usivity of transparent and semitransparent materials, which does not require cutting out samples from the test object and two-sided access to it. To increase the coeffi cients of absorption and emission of visible and infrared radiation of the accessible surface, thin opaque coatings or targets with a diameter of several tenths of a millimeter were used. The method was tested on eight optically transparent polymeric, amorphous, and crystalline materials diff ering in composition, spectral characteristics of light absorption, surface condition and overlapping about 2 orders of magnitude in thermal diff usivity. The described procedure demonstrated a small random error (0.5% for polymethyl methacrylate, 1.1% for polycarbonate, 2.3% for fused quartz, 3.3% for monocryslalline NaCl) at a speed of about 10 s, which makes it possible to use it for rapid diagnostics of newly created heat-shielding materials and elements of power optics. [ABSTRACT FROM AUTHOR]

The review is dedicated to characteristics of the mechanical behavior of various materials at submicro- and nanoscale levels. To a large extent, progress in this area is determined by the development of a large family of methods for precision force nanotesting, which have been referred to as "nanoindentation". However, nanomechanical properties are studied to date not only and not so much by nanoindentation methods in narrow sense, i.e., the methods of local deformation of macro-, micro-, and nanoscale objects. Force nanomechanical testing is interpreted more broadly and includes the application of small forces to the test object and the precise measurements of deformation with nanometer resolution under uniaxial compression, tension, bending, shear, and torsion by various methods with simultaneous in situ registration of their microstructural parameters by electron microscopy and X-ray diffraction methods. The main research directions developed in the last decade to improve experimental approaches and the results on single-, micro-, and nanocrystalline materials, composites, films, and coatings obtained by means of these approaches in amorphous solids and biomaterials (tissues, living cells, and macromolecules) are described. Particular attention is paid to size effects and atomic deformation/fracture mechanisms at the nanoscale. This review is a natural continuation and development of the author's review published in Phys. Solid State, vol. 50, issue 12, p. 2113 (2008), in which the specifics of the nanomechanical properties of solids are analyzed, and describes both the basic concepts of nanomechanical testing of materials and the latest advances in this area. [ABSTRACT FROM AUTHOR]

The relationship between the mechanical properties of anisotropic materials and their thermophysical characteristics was experimentally revealed using the example of Scots pine (Pınus sylvéstris L) wood. By measuring the hardness and principal components of the thermal diffusivity tensor, on three sections (normal to the fibers, tangential, and radial) at different wood moisture content, it has been shown that this relationship can be described by linear functions. This makes it possible to carry out an express assessment of the mechanical properties of anisotropic materials, which normally require labor- and material-intensive destructive tests, by means of contactless nondestructive determination of their thermophysical characteristics using the method of dynamic thermography. [ABSTRACT FROM AUTHOR]

In this paper, we present the results of the application of new methods of monitoring and diagnostics based on a computer analysis of multiscale dynamic thermographic patterns. Depending on the size of the inspected area, as well as the nature, location, orientation, and size of defects, various energy sources, such as an airflow, focused laser beam, and point contact, were used for probing dynamic heating of the product under control. The nonstationary thermal image of the monitored area was recorded by a high-resolution thermal camera and then analyzed by using original model approaches and developed specialized software. The development of defects was initiated by a calibrated local power load using the built-in force generator. This allowed identifying dynamic (prone-to-growth) defects and assessing the degree of their danger for further operation and the residual resource of the product. Using the proposed methods, defects of various types (cracks, delaminations, detachments, and degradation of coatings, defects in welding and adhesive joints, deposits of transported substances, etc.), sizes (from fractions to tens of millimeters), and location in the product (near both the outer and inner surfaces of vessels, pipelines, reactors, tanks, etc.) can be detected and quantitatively characterized. The developed techniques also allow determining the thermophysical characteristics of the material, in particular, the thermal diffusivity coefficient with an accuracy better than ±3%. [ABSTRACT FROM AUTHOR]

An experimental-computational method of non-stationary thermal diagnostics and non-destructive testing of metallic and non-metallic sheaths and plates, including their inner surfaces inaccessible for direct inspection, by analyzing a non-stationary temperature field generated by the point dynamic heating of the outer surface of the sheath and registered by a thermal imaging device is described. [ABSTRACT FROM AUTHOR]

The energy spectrum of local charge-carrier trapping centers in C60 single crystals is studied in terms of the theory of space-charge-limited currents in the Gaussian approximation. The energy distribution of these centers in the energy gap is found, and the type and parameters of this distribution are determined. [ABSTRACT FROM AUTHOR]

It is shown, that the photoconductivity of C 60 single crystal essentially depends on a spin state of the intermediate electron‐hole pairs. The distance between components of electron‐hole pairs in states with uncorrelated spins and their lifetime were estimated as R ≥3.4 nm and τ∼⃒10 -9 s. [ABSTRACT FROM AUTHOR]

The rate of the radiation-stimulated change in the microhardness of silicon single crystals exposed to irradiation with a low-intensity flux of beta particles (105 < I < 2.9 × 106 cm−2 s−1) is studied as a function of the radiation intensity. The temperature is determined at which the microhardness H = H τ reached in a time τ under low-intensity beta irradiation regains its initial value H 0. The results obtained indicate that complexes containing two vacancies play a dominant role in the radiation-stimulated softening of silicon single crystal [ABSTRACT FROM AUTHOR]

Radiation-stimulated and postradiation changes in the microhardness of silicon single crystals exposed to irradiation with a low-intensity flux of β particles (I = 9×105cm–2s–1,W = 0.20 + 0.93 MeV) are studied. It is established that the inversion of the radiation-induced plastic effect occurs at a characteristic irradiation time τc = 75 min; i.e., irradiation of silicon single crystals for a time τ < τc leads to nonmonotonic reversible hardening, whereas nonmonotonic reversible softening is observed under irradiation for a time τ > τc. It is demonstrated that there exists a correlation between the nonmonotonic dependences of the microhardness and the concentration of electrically active defects at acceptor levels with energies Ec – 0.11 eV, Ec – 0.13 eV, and Ec – 0.18 eV on the irradiation time. © 2005 Pleiades Publishing, Inc. [ABSTRACT FROM AUTHOR]

The deformation dynamics of nanovolumes in crystalline, quasicrystalline, and amorphous solids is studied experimentally using continuous nanoindentation with a resolution of 0.1 nm. The elastic limits of some materials are determined in a nanocontact region. A jumplike transition to a plastic flow (which is equivalent to a drop in yield in uniaxial macroscopic tests) is revealed and studied. The dynamics and statistics of an unstable plastic flow in strain-aging alloys are analyzed. The specific features of a local stress–strain curve associated with a phase transformation under an indenter and with microcrack nucleation are revealed. The load-carrying ability of a material upon nanocontact loading is shown to be many times its macroscopic yield strength and to approach the theoretical ultimate strength even in plastic materials. The relaxation processes occurring in submicrovolumes after unloading are found to induce an elastic aftereffect that is much larger than that in macroscopic tests. In Si and Ge single crystals, the effect of a jumplike increase in the cracking resistance with the strain rate is detected. © 2005 Pleiades Publishing, Inc. [ABSTRACT FROM AUTHOR]

A technique for the determination of the strain-rate sensitivity of hardness during dynamic nanoindentation is proposed. The strain-rate sensitivities of the dynamic hardnesses of a wide class of materials (fcc metals, carbon steels, bulk amorphous metallic alloys, ionic and covalent crystals, polymers, and ceramics) are determined. The variation of these strain-rate sensitivities with the relative-strain rate (in the [variant_greek_epsilon] range from 3×10–3 to 5×103s–1) and the indentation depth (in the range from 30 nm to 2μm) is studied. © 2005 Pleiades Publishing, Inc. [ABSTRACT FROM AUTHOR]

The study is aimed at the establishment of regions of stable (monotonic) and unstable (jumpwise) plastic flow in bulk amorphous Zr46.8Ti8Cu7.5Ni10Be27.5 alloy under the conditions of local deformation. The characteristics of the jumpwise plastic flow in bulk amorphous Zr46.8Ti8Cu7.5Ni10Be27.5 alloy are studied by the method of continuous nanoindentation (depth-sensing testing) in the range of strain rates [variant_greek_epsilon] from 10–2 to 104s–1. The boundaries between the regions of homogeneous and localized plastic strain are established and the fractions of monotonic and jumpwise plastic strain under the indenter are determined. © 2005 Pleiades Publishing, Inc. [ABSTRACT FROM AUTHOR]

An influence of steady, pulse and microwave magnetic fields on mechanochemical reactions between structural defects in doped ionic crystals has been studied. The effects of dislocation depinning, dislocation mobility increase, macroplastic unhardening and magnetoresonant softening in magnetic fields have been revealed. It is shown that the magnetosensitive spin-dependent reactions between structural defects is the reason of magnetoplastic effects in nonmagnetic crystals. It means that the electron and nuclear spin states of the paramagnetic defects play an important role in the formation of mechanical properties of crystals in magnetic fields and without them. [ABSTRACT FROM AUTHOR]

Possible mechanisms of a number of magnetoplastic effects in magnetically disordered crystals are analyzed in the context of the chemical kinetics of reactions occurring in a system of structural defects upon plastic deformation. Particular attention is given to spin-dependent reactions between real-structure elements containing paramagnetic centers (dislocation cores, impurity centers, electronic excitations, and so on). It is shown that reactions of several types may occur between these elements, and, in some cases, the relative deformation rate can be related to the rate constants of intracrystalline spin-dependent reactions. © 2004 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

This paper is an overview of the studies into the effect of weak magnetic fields on the structure and mechanical properties of nonmagnetic solids of various nature (ionic, covalent, molecular, and metallic crystals, polymers, etc.). The various effects and aftereffects initiated by static, pulsed, and microwave magnetic fields that have been discovered over the past 15 years are classified and critically analyzed. The thermodynamic and kinetic aspects of the magnetic-field sensitivity of real solids with structural defects containing paramagnetic centers (electrons, holes, radicals, excitons, etc.) are discussed. Possible mechanisms for the effect of a weak magnetic field on the defect structure of crystals are considered. Special attention is given to the most developed chemical-physical theory of spin-dependent reactions between mobile particles and unpaired electrons. Interpretation of magnetoplastic effects is proposed in terms of the spin, electron, molecular, and dislocation dynamics of the complex multistage processes initiated by a magnetic field in a system of metastable structural defects. © 2004 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

A reversible variation in the microhardness of C[sub 60] single crystals induced by low-dose β irradiation is found to change sign in the vicinity of the phase transition at T[sub c] = 250–260 K. Radiation hardening is observed at T < T[sub c] and radiation softening, at T > T[sub c]. The kinetic characteristics of the β-induced variation in the microhardness of C[sub 60] and its recovery to the initial value are studied in the temperature range 170–350 K. Both processes are found to be thermally activated. The activation energies are determined and are shown to be different for sc and fcc lattices. © 2004 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

Comparative research of the excitation photoconductivity spectra (quantum light energy 2–5 eV) of C60 single crystal in and out of magnetic field at the temperature T = 250–350 K has been carried. The spectral evolution at this temperature range is described. It is shown that the spectra changes abrupt at temperature T1 ∼ 260 K and T2 ∼ 315 K. An increase in the photoconductivity up to 15% was observed in the magnetic field (B = 0.4 T) within the photon energy range 2.5–4.5 eV. Local photoconductivity peak's appearances in the magnetic field have been proven that the charge transfer excitons take part in a photoconductivity. [ABSTRACT FROM AUTHOR]

Depth-sensing (indentation) testing is used to study the characteristics of a serrated plastic flow in a Pd[sub 40]Cu[sub 30]Ni[sub 10]P[sub 20] bulk amorphous alloy, and the boundaries between the regions of serrated and homogeneous plastic deformation are determined. [ABSTRACT FROM AUTHOR]

The suppression of plasticity sensitivity of a C[SUB60] fullerite to the action of a magnetic field is revealed. It is found that the C[SUB60] fullerite undergoes temporary softening due to irradiation with ultralow (<0.1 cGy) doses of β and γ radiation. [ABSTRACT FROM AUTHOR]

An improved nanoindentation technique was developed for dynamic investigation of the time-dependent properties of materials under conditions close to real nanocontact interaction during dry friction, abrasive wear, milling, mechanical alloying and so on. For these purposes the duration of the loading- unloading cycle was reduced to 20 ms and a nanocontact fatigue test was performed with the number of reloading cycles reaching 10[sup 3]-10[sup 5]. [ABSTRACT FROM AUTHOR]

A high-resolution dynamic nanoindentation technique has been developed (spatial resolution, about 1 nm; time resolution, about 50 µs). In addition we were able to record the electrical polarization of the indentation zone with a time resolution of about 100 ns. It has been established that the process of the indenter penetration under step-like loading conditions can be described as consisting of several distinct stages (as many as four in some cases) that differ in kinetics and activation parameters. Relative contributions of non-equilibrium point defects and dislocations in each stage are discussed. [ABSTRACT FROM AUTHOR]

Methods of dynamic nanoindentation were used to study unstable modes of plastic flow in micro- and submicrovolumes of the Al–3% Mg alloy. It was established that, depending on the rate of loading and dimensions of the deformed region, various regimes of unstable plastic deformation are realized. In the course of deformation, the irregular deformation curve (corresponding to a random process) reveals a quasi-periodic behavior with a characteristic amplitude of hardness oscillations. © 2002 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

A modified setup and a method of dynamic indentation with a triangular symmetric force pulse of controllable amplitude and duration are employed for analyzing the time-dependent elastic properties of ZrO[sub 2]-based ceramics in a contact time range of 20 ms–4 s. It is shown that the duration of the loading–unloading cycle considerably affects the dynamic hardness: the variation of the contact time from 20 ms to 4 s leads to a 20% change in the dynamic hardness for P[sub max] = 25 mN. The variation of the hardness sensitivity m to the strain rate upon a transition from the initial stage of indenter intrusion to the next stages from m[sub 1] = 1.56 to m[sub 2] = 0.49 may point to the difference in the mechanisms of mass transfer of a material under an indenter at these stages. © 2001 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

Low-cycle surface fatigue is still relatively poorly investigated, especially in the case of accumulation of surface fractures during nanocontact interactions between solids. A new technique of modeling fatigue during a short nanocontact interaction based on repeated dynamic nanoindenting is proposed. The results of investigation of model LiF crystals and industrial ZrO[sub 2] ceramics show that, at a small number of cycles N of about 20, the material is hardened under the indenter. As N increases, the hardening is replaced by a loss of strength reflected in the formation and growth of microcracks. [ABSTRACT FROM AUTHOR]

It is found that the magnetoplastic effect in C[sub 60] single crystals in a pulsed magnetic field with induction larger than 10T changes its sign in the vicinity of the phase transition at T[sub c] = 250-260 K: crystal strengthening is observed for T < T[sub c], and softening occurs for T > T[sub c]. This indicates a change in the crystal lattice structure in the magnetic field. [ABSTRACT FROM AUTHOR]

A new type of magnetoplastic effects in polymers is revealed. This effect cannot be explained by the reorientation of macromolecular units that possess a magnetic susceptibility anisotropy. It is shown that the joint action of magnetic and electric fields and the rotational mobility of side groups in macromolecules are factors of crucial importance in changing the plasticity of polymers in pulsed magnetic fields. [ABSTRACT FROM AUTHOR]

The kinetics of free growth of ice in a distilled-water film supercooled to -30°C was studied by the video recording technique in the polarized light. In the supercooling range 12 < δT < 16 K, a first-order kinetic morphological transition was observed between the structure formed by needlelike crystals of ice and the quasiadiabatic "structure" of single grains having the shape of planar platelets with the thickness proportional to the thickness of the water film and relative supercooling. It was found that this transition is accompanied by jumplike changes in the main crystallization parameters such as the growth rate of grains, their size and number, their kinetic behavior, and the fractal dimension of the structure. [ABSTRACT FROM AUTHOR]

Electromagnetic and acoustic emission was found to accompany crystallization of distilled-water droplets supercooled to -30°C. It was shown that the front of an electromagnetic pulse provides the information on growth kinetics of ice in a supercooled droplet. A mechanism of electromagnetic pulse generation based on the Workman-Reynolds effect is proposed. [ABSTRACT FROM AUTHOR]

The purpose of this work was to investigate the plastic properties of Ca- or Eu-doped NaCl and KCl single crystals in crossed constant and microwave magnetic waves under paramagnetic resonance conditions. It was found that when the photon energy of the microwave field equals the Zeeman splitting of the electronic spin sublevels, resonance softening of the crystals, manifested as an increase in the free path of individual dislocations and the macroplastic flow velocity as well as a decrease of the microhardness of the crystals, is observed. It was established that metastable Ca- and Eu-impurity complexes, which are also sensitive to the constant magnetic field in the absence of the microwave field, as well as complexes formed by dislocations and point defects are responsible for resonance softening. [ABSTRACT FROM AUTHOR]

Several radically new independent insitu techniques for characterizing physicomechanical properties of materials in microvolumes are described. In particular, mechanisms behind the formation of an indent and the surrounding deformation zone were studied at a microlevel. With ionic crystals, it was demonstrated that indentation, followed by the formation of the deformation zone, passes the following stages: purely elastic deformation stage, the stage of monoatomic displacement of a material from under the indenter; and a number of final stages where dislocation plasticity is essential. Kinetic, dissipative, and activation parameters of indentation were determined, and basic mass transfer micromechanisms for each of the stages were elucidated. © 2000 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

It is established that exposing crystals to a pulsed electric field with an amplitude of ∼10[sup 3] kV/m creates metastable states of the point defects, while a magnetic field with an induction of 7 T causes them to relax. © 1998 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Results are reported here of a study of the resonance effect of a constant magnetic field and a variable magnetic field crossed with it on the rate of macroplastic deformation and motion of edge dislocations in NaCl crystals. The frequencies of the variable magnetic field at which the maximum variations in the plasticity of the crystals are observed correspond to the resonant frequencies for transitions between the Zeeman sublevels in paramagnetic complexes of point defects and complexes consisting of a point defect and a dislocation. Analysis of the radiofrequency spectra obtained enabled us to establish the role of intercrystal reactions in the formation of the mechanical properties of the crystals. [ABSTRACT FROM AUTHOR]

The aim of this work is to examine the influence of a weak (on the energy scale) magnetic field on the state of dislocations and point defects in ionic crystals. It is found that complex point defects existing in a metastable state are sensitive to a magnetic field B∼1 T. The contributions are identified, and the kinetics of various types of reactions within the structural defects and between them leading to plastification of the crystals in a magnetic field are determined. The effect of light on the sensitivity of the point defects to a magnetic field is described, and the spectral characteristics of this effect are determined. A resonant effect of the combined action of a weak constant magnetic field and a high-frequency magnetic field on the dislocation mobility is found to occur when these fields satisfy the conditions of electron paramagnetic resonance. [ABSTRACT FROM AUTHOR]

It is found that a ∼10 T magnetic field influences the microhardness and the photo- and electroluminescence of ZnS single crystals containing microtwins. It is established that a magnetic field irreversibly changes the properties of the crystal, leading to relaxation of the metastable states of structural defects. © 1999 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A change in the macroplastic deformation rate and an increase in the travel distances of edge dislocations are observed in NaCl single crystals placed in crossed dc and rf magnetic fields. The magnetic-field frequencies at which softening maxima are observed correspond to the resonance frequencies of transitions between Zeeman sublevels in paramagnetic complexes of structural defects. © 1998 American Institute of Physics. [ABSTRACT FROM AUTHOR]

This paper presents the results of an investigation into the effect of a pulsed magnetic field on the state of linear and point defects in ionic crystals. For different amplitudes (1-7 T) and pulse lengths (3 × 10[sup -5] to 10² s) of the pulsed field the kinetics of the transformation of defects into a new state and their relaxation after the field is turned off are studied in the temperature range 77-400 K. It is found that the relaxation of the states of point defects is mainly through recombination, and the change of state of the dislocations and of the point defects contribute nonadditively to the change in the dislocation mobility. The exposure of the crystal to a magnetic field leads to an increase in the dislocation mobility when the sample is mechanically stressed and to a decrease in the dislocation displacement with a second field pulse. [ABSTRACT FROM AUTHOR]

This paper presents the results of an experimental investigation into the mobility of edge dislocations in KCl:Ca single crystals and the effect of a static magnetic field of 0.3 T on the dislocation mobility. The experiments on the effect of a magnetic field on the dislocation mobility were carried out with the use of a high-resolution (1 ms) method that permits in situ measurements of the sample dipole moment induced by the motion of charged dislocations as the crystal is being deformed. It is found that the starting stress is reduced in a magnetic field and the activation volume for overcoming of point defects by the dislocations is increased. It is further found that the magnetic field increases the rate of motion of the dislocations at the initial stage of deformation (to the point of dislocation multiplication) but has no effect on the mobility in the multiplication stage. [ABSTRACT FROM AUTHOR]

The influence of the type and concentration of a dopant (P, Sb, B) on the dynamics of the transformation of a system of structural (intrinsic and radiation-induced) defects of silicon under low-intensity electron irradiation is investigated. A qualitative model is proposed for the formation of the complexes of secondary radiation defects responsible for the maxima of beta-induced softening of silicon single crystals. [ABSTRACT FROM AUTHOR]

Weak magnetic fields with an induction B = 0.28 T are found to have an effect on the transformation of subsystems of structural (intrinsic and radiation-induced) silicon defects under irradiation with a low-intensity flux of beta particles ( I = 105 cm−2 s−1). The effect of a weak magnetic field leads to an increase in fluences at which the disordering exhibits maxima. [ABSTRACT FROM AUTHOR]

Reversible softening of silicon single crystals under β irradiation with low doses (D < 1 cGy) is revealed. The peaks observed in the dependence of the microhardness of silicon on the fluence are explained by the multistage competing processes of transformations of radiation-induced defects. © 2004 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

Dynamic indentation is used to study the character of a plastic flow during room-temperature deformation of an A1-2.7% Mg alloy in micro- and submicrovolumes (the indentation depth is varied from 50 nm to 15 μm) at strain rates varying in the range 0.00005-1 s-1. In this region of parameters, the boundaries of stable deformation and two modes of unstable deformation have been found. [ABSTRACT FROM AUTHOR]

The effect of crystal orientation on the photogeneration of free charge carriers was studied for C60 single crystals in a weak magnetic field. The photoconductivity sharply depends on the orientation of magnetic field with respect to the crystallographic directions, showing a 5–8% increase for seven axes of the C60 crystal. © 2004 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

The process of elastic and viscoelastic recovery in locally strained submicron regions in various solids has been studied. The influence of the scale and loading rate factors on the process parameters is revealed. © 2004 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

Examines the features of the elastoplastic transitions under the local deformation of nanoregions of a material by ultralow loadings. Observance of jumps on the surfaces of spall; Indications of a substantial difference from macrotests; Probable causes for the formation of jumps; Corroboration for the probability of the existence of stress concentrators.

Analyzes the photoconductivity excitation spectra for fullerene single crystals in a magnetic field. Charge-transfer exciton states; Dipole optical transition.