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Aluminum-matrix composite materials based on commercial-purity AD0 aluminum are studied. An SiC powder and Al2O3 whiskers and nanofibers are selected as fillers. These fillers slightly are found to weakly increase the density and exert a modifying effect on the microstructure. The grain refinement is maximal (by 35.3%) in the composite modified with Al2O3 nanofibers. This composite exhibits a quasi-brittle character of fracture and the maximum fracture energy.

The absorption spectra of a water molecule perturbed by argon pressure were measured in the 6700–7650 cm−1 region. The spectra were recorded at an IFS 125HR Fourier spectrometer with a high signal-to-noise ratio at a room temperature with a spectral resolution of 0.01 cm−1. The argon pressure was varied from 0 to 0.9 atm. Using three line profile models (the traditional Voigt profile; the quadratic Voigt profile, which depends on the speed of an absorbing molecule; and the Hartmann–Tran profile), the parameters of the absorption lines of the water molecule were calculated. A better agreement with the experimental data is provided by the Hartmann–Tran profile. It is suggested to use a relatively simple Voigt profile for mass measurements at pressures above 300 mbar.

Aluminum-matrix composite materials based on commercial aluminum AD0 have been investigated. SiC powder, whiskers and Al2O3 nanofibers were chosen as fillers. It was found out that the selected fillers slightly increase density and have the modifying effect on the microstructure. The maximum grain refinement (by 35.3%) was achieved in the composite modified with Al2O3 nanofibers. This composite exhibits a quasi-brittle fracture pattern and the greatest fracture work.

The choice of the composition of the components of a composite material that determines its prospects and demand has been substantiated. Liquid-phase combination is used to fabricate billets of an aluminum-matrix composite material of a new composition. The technological problems of introducing discrete Al2O3 nanofibers into an aluminum matrix are solved. A copper powder is used to overcome surface tension forces and to ensure a uniform reinforcing component distribution. When the components of the composite material are prepared, the reinforcing phase consisting of a transport powder and nanofibers is ground and the resulting conglomerate is introduced into a melt to form a composite material. The hardness of the reinforced specimens is higher than the hardness of the matrix, and sufficient uniformity of the hardness distribution over the cross section demonstrates the uniformity of introduced component distribution. An analysis of the fracture of specimens demonstrates a clear predominance of plastic deformation for the initial matrix alloy and an embrittlement effect in the case of reinforcement. Structural studies on a macrolevel show the signs characteristic of brittle fracture, and scanning electron microscopy (Tescan Vega IILMH microscope) studies demonstrate signs of ductile fracture. The fabrication of high-quality specimens and the results of studying the structure and properties confirm the efficiency of the technology developed for the introduction of fillers.

—The spectrum is obtained and the time dependences of fractoluminescence signals upon fracture of the surface of quartz are studied. The analysis of the obtained data has shown that at fracture, clusters of four cracks having a size of a few nm appear. Crack formation is associated with the destruction of barriers precluding the motion of dislocations along the sliding planes. The distribution of cracks by sizes (surface areas of crack walls) obeys the Gutenberg–Richter law.

The behavior of carbon fiber – plasma composite in strong pulse fields is investigated. Itis shown that the principal current travels through the plasma which shunts the resistance of the carbon fiber, preserving the fiber against complete disintegration. The contribution of the fiber to the conduction of the composite is determined by the bias current that arises as a consequence of the polarization of is dielectric component in an alternating electrical field.

The surface of amorphous SiO2 samples, which receives various doses of implantation by Ar+ ions with an energy of 40 keV, undergo a point shock impact. The kinetics of the accumulation of microcracks are investigated using the acoustic emission method. The square of the amplitude of the acoustic emission pulse appears to be proportional to the energy released during the formation of a microcrack. It is demonstrated that the energy distribution in the damaged samples that receive a dose of up to 1 × 1015 Ar+/cm2 (inclusive) is random and identical to the distribution over the surface not subjected to implantation. With the dose of 5 × 1015 and 1 × 1016 Ar+/cm2, the energy distribution follows the typical power law for correlated events. In the implanted material, the local destruction of the surface shows signs of a plastic flow.

—The experiments on the determination of paleointensity Banc of the Earth’s magnetic field by Thellier method on basalts of the Berd (Jurassic) and Paravakar (Cretaceous) collections sampled in the northeastern Armenia in 2006 revealed an anomalous behavior of the Arai–Nagata diagrams. The anomaly manifests itself by a sharp drop in the intensity of natural remanent magnetization (NRM) under heating of samples to about 400°C, which is accompanied by a very weak acquisition of partial thermoremanent magnetizations (pTRMs) in this temperature interval. The further increase in temperature leads to the opposite phenomenon—an unexpectedly sharp rise in pTRMs intensity with almost no decrease in NRM, which creates the L-shape of the Arai–Nagata diagram. A similar phenomenon of a steep decline during thermal demagnetization was also established for remanent saturation magnetization Mrs(T). We carried out a number of magnetomineralogical experiments from which we conclude that, consistent with the hypothesis suggested by (Kosterov and Prevot, 1998), the sharp drop in Mrs(T) and NRM(T) curves is caused by the transitions of the domain state from a metastable configuration to a more stable one. These transitions are initiated by the processes of single- and heterophase oxidations of primary titanomagnetites under the laboratory heating of samples to moderate temperatures.

Time series of acoustic emission pulses are recorded when the surface of MgAl2O4 ceramics is damaged by the introduction of a Vickers pyramid. Based on the data of the frequency analysis of the emitted sound, the ratio of the size of intra- and intergranular microcracks is estimated depending on the load on the indenter. The statistical analysis shows that the energy distribution in acoustic pulses is always random, typical of the uncorrelated development of a fracture.

Behavior of promising aluminum-base composite materials reinforced with silicon carbide particles and discrete alumina fibers is analyzed under impact loading conditions. Workpieces for test specimens are prepared by liquid-phase combination of the components. Results of impact bending tests and analysis of fracture surfaces are used to determine the effect of fillers on material impact behavior and to evaluate the effect of reinforcement.

SUMMARY The natural remanent magnetization (NRM) of the ocean floor is carried by titanomagnetite grains that undergo low-temperature oxidation after initial cooling. Progressing oxidation is known to generate shrinkage cracks in grains larger than approximately 5 μm, and is suspected to control the long wavelength variation of NRM-intensity across the ocean floor. Here we develop a quantitative theory of single-phase oxidation and crack formation by solving the vacancy-diffusion equation that describes the oxidation process for spherical titanomagnetite particles, where the diffusion coefficient strongly decreases with vacancy concentration. The latter dependence has been experimentally demonstrated and is essential to explain the peculiarities of the observed variations of oxidation-degree with ocean-floor age. The calculated diffusion profiles provide the exact stress distributions inside oxidized titanomagnetite spheres, and predict a size limit for shrinkage-crack formation that agrees with microscopic observations of crack appearance in ocean-floor basalt samples. The new diffusion model provides a unified explanation of long-known experimental facts that (1) temperatures for the onset of low-temperature oxidation during laboratory heating are theoretically estimated as 200–400 ○C, depending on grain size and (2) that heating to 400–500 ○C is required to obtain a sufficiently high degree of oxidation z ≈ 0.8 for the development of high-temperature exsolution lamellae. Calculations for ocean-floor conditions quantitatively suggest that a rapid decrease of NRM intensity during the first 40 ka results from a deflection of magnetization by strong stresses that emerge in titanomagnetite grains of subcritical sizes, and randomization of domain-state by crack formation in larger grains.

It is shown by IR spectroscopic investigation that ceramic zinc telluride contains water and carbon dioxide adsorbed on the surface of cavities between crystallites. It is found that hydroxyl groups occur on the surface of products as early as in the polishing stage, while the groups belonging to CO2 are adsorbed during storage under normal conditions. It is also established by the photoluminescence method that mechanical fracture of ceramics manifests itself in the crystallite composition’s deviation from stoichiometry and narrowing of the band gap.

Point damage to the surface of ZnS ceramics synthesized by chemical vapor deposition (CVD) was produced by means of either a sharp striker impact or slow indentation of a Vickers pyramid and monitored by measuring time series of strain-induced acoustic emission response. In the case of impact, the duration of acoustic emission was 0.3–0.5 ms, while the indentation was accompanied by a 3- to 5‑ms-long initial active phase of emission followed by the generation of weak sporadic signals over a time period of 80–100 ms. Statistical analysis of the recorded time series showed that the energy distribution in impact-induced acoustic pulses was always random (Poisson’s type), while the signals induced by indenter penetration obeyed a power law of the Gutenberg–Richter type. The different characters of energy release observed for the two types of load application are explained by specific features of the temporal regime of self-organized dislocations, the accumulations of which acted as the centers of microcrack nucleation.

—The growth rate and size of microcracks formed in the surface layer of basalt and tonalite (granodiorite) at friction are studied using luminescence. It is found that upon breaking of crystal lattices of labradorite and quartz contained in these rocks, triboluminescence signals arise. Each signal corresponds to an embryo microcrack whose surface contains electronically excited free radicals ≡Si–O–, Fe3+ ions, and electron traps. The average growth rate of embryo microcracks in basalt varies from ~0.6 to ~1 km/s and in tonalite, from ~ 0.7 to ~1.3 km/s. The sizes of embryo microcracks in basalt range within ~3 to ~5.5 μm and in tonalite from ~3.5 to ~6.5 μm.

In this paper, we employ SiC super hard ceramics that are widely used for the manufacture of individual means of protecting people from point impact effects and MgAl2O4 ceramics transparent in a wide spectral range that are used for protective screens of optical devices of aircraft, which are exposed to solid dust particles and atmospheric precipitation. Here, we study generation and relaxation of microcracks under impact action by using acoustic emission and electromagnetic emission, respectively. Since the mechanism of generation of these types of emissions has a different origin, then a comparison of the emission activity of one and another type allowed identifying general and individual patterns of impact damage to SiC and MgAl2O4 solid ceramics.

Monte Carlo numerical simulation of the formation of chemical remanent magnetization (CRM) by the mechanism of the growth of volumes from superparamagnetic (SPM) to single-domain (SD) in the ensembles of magnetostatically interacting particles, thermoremanent magnetization (TRM), and experiments on determining paleointensity by the Thellier–Coe and Wilson–Burakov methods are carried out. The obtained results agree with the Smirnov–Tarduno hypothesis (Smirnov and Tarduno, 2005) that the similarity of the spectra of blocking temperatures Tb of CRM and TRM can be due to the narrowness of the interval of the blocking temperatures Tb of CRM and TRM, with the reservation that the similarity can be observed on part of the total interval of the Tb spectrum provided that this interval accommodates a significant fraction of the total CRM intensity. The analytical examination of the case of non-interacting particles (sparse concentration of grains) shows that in this case, the (quasi-)linearity of the Arai–Nagata diagrams is due to the presence of a plateau on the curves of the derivative dCRM/dpTRM (pTRM is partial thermoremanent magnetization) which emerges in a narrow spectrum of blocking temperatures. The results of the numerical experiments suggest that at a particle concentration of above 0.2% magnetostatic interaction leads to the practically full linearity of the Arai–Nagata diagram over a significant interval of the total spectrum of blocking temperatures for CRM. At the same time, on the remaining temperature interval, both the Arai–Nagata diagrams and the CRM(TRM) curves are substantially concave, indicating the lack of similarity between the spectra of blocking temperatures for CRM and TRM. The analysis of the empirical data revealed their resemblance, up to a certain point, to the results of simulation but at the same time clearly demonstrated the noticeable distinction between them, associated with the significant differences in the conditions of the numerical and laboratory experiments.

—Luminescence caused by friction of heterogeneous solids (basalt and granite) was investigated, the spectra are recorded, and the dynamics of the luminescence intensity were studied. Under friction, the crystal lattices of these bodies are destroyed, and the luminescenting ≡Si–O– free radicals and Fe3+ ions and electron traps located on the surface of microcracks are formed. The dynamics of accumulation of microcracks is investigated at a time resolution of 2 ns, and their sizes determined to be about 6–10 μm.

Zinc sulfide and zinc selenide ceramic samples prepared by hot pressing (HP) and chemical vapor deposition (CVD) have been subjected to dry grinding simulating dust erosion of these materials under real service conditions. It has been demonstrated that photoluminescence measurements allow one to follow the degradation of the crystal structure of ceramic grains by monitoring the intensity of structure-sensitive emission bands. The crystal structure of ZnS, a harder material, has been shown to be less sensitive to abrasion. Moreover, the abrasion resistance of the ceramics produced by CVD exceeds that of the HP ceramics of the same composition.

The structure of the surface layer of a heterogeneous solid body (xenolite) before and after friction is studied by infrared and Raman spectroscopy. Before friction, the layer contained hornblende and pyroxene crystals. The friction resulted in partial transformation of pyroxenes into hornblende and the latter was transformed into montmorillonite clay. The xenolite surface is covered with a ~60-nm-thick layer of water.

The dynamics of emission of positively charged ions from the granite surfaces containing different concentrations of quartz and feldspar under the action of a shock wave is investigated with a time resolution of 2 ns. The ions are assumed to be emitted at the instants of emergence of dislocations moving in intersecting glide planes at the sample surface. Defects in the form of extended “grooves” are formed in the region of emergence of dislocations. A compressive load suppresses the defect formation.

The vibrational-rotational absorption spectrum of water vapor was recorded and analyzed in the visible spectral region from 19480 to 20500 cm−1. The measurements were carried out using an IFS-125M Fourier spectrometer with a resolution of 0.05 cm−1 at a pressure of 26.3 mbar, a temperature of (24 ± 1)°C, and optical path 24 m. We used a multipass White cell with a base length of 60 cm. A light-emitting diode was used as a radiation source. The signal-to-noise ratio was about 20000. The list of more than 420 lines has been compiled as a result of the analysis the spectrum, which includes line centers, intensities, and quantum vibrational-rotational numbers. More than 220 vibrational-rotational energy levels of 21 upper vibrational states have been determined from the experimental data.

Friction-induced changes in the structure of the surface layer of basalt and granite samples extracted from a well in the triggered seismicity zone in the Koyna–Warna region, India, have been studied by infrared, Raman, and photoluminescence spectroscopy. It has been found that friction leads to a partial degradation of quartz, albite, and clinopyroxenes crystals. Instead of these crystals, a thin layer of a mineral with a low coefficient of friction—kaolinite—is formed on the surface.

Mechanoluminescence (ML) in ductile solids is caused by the motion of charged dislocations in the deformable material. Interatomic bond ruptures followed by electronic structure reconfiguration are the main source of ML in brittle bodies. We studied ML in ceramics composed of mixed ionic/covalent ZnS and ZnSe compounds, which are generated during impact loading higher than the limit deformation. Depending on synthesis method and thermal treatment, the resulting ceramics had different size and geometry of grains and intergrain boundary structure, which presumably may have a significant effect on the dislocation glide. In both materials, the time sweeps of ML pulses have two well-resolved peaks. The position of the peaks along the time axis is substantially dependent on the size of ceramic-forming grains and, to a smaller extent, on the barrier properties of intergrain boundaries. The first peak is associated with plastic deformation preceding disintegration of the crystal structure. The second peak emerges upon crack nucleation as interatomic bonds are ruptured and the material is undergoing local deformation in tips of propagating cracks. The distributions of ML pulse amplitudes (the dependences between the number of pulses and their amplitude) calculated for both peaks individually follow the power law, which demonstrates that the electronic processes having different excitation mechanisms (dislocation motion vs bond rupture) are correlated.

Absorption spectra of methane in the 11000–11400 cm–1 spectral region were recorded with an IFS-125M Fourier spectrometer at pressures from 11 to 100 mbar, a room temperature, and a spectral resolution of 0.03 cm–1. A multipass cell 60 cm long with 44 passes provided a total path length of 2640 cm and threshold sensitivity to absorption of about 10–8 cm–1. Line centers, intensities, self-broadening, and selfshift coefficients of methane lines were determined by fitting Voigt profile parameters.

The results of mechanoluminescence (ML) and acoustic emission (AE) studies of the response of the ceramic materials ZnS and ZnSe to impact damage to the surface are presented. The experiment simulates the process of dust erosion of optical components made from these materials and installed on high-speed mobile carriers. A comparison of a time series of light and sound emissions showed that ML manifests two peaks approximately 50 – 200 and 150 – 200 μsec after impact, while AE occurs in a single peak near 200 μsec. This result is explained by plastic deformation of the material at the first stage of fracture and subsequent formation of microcracks.

The introduction of Si+ ions and ions of other elements into amorphous silicon dioxide during their interaction causes damage to the structural bonds, which is observed in the vibrational spectral bands. Pure SiO2 has no optical transitions but the bands of induced point defects appear in the photoluminescence spectrum when ions/neutrons are introduced. The generation of photoluminescence-active defects by fluxes of Ar+ ion and thermal neutrons is compared. It is shown that the nature of damage to the structure is associated with both the specifics of the synthesis/processing of the material and the features of the interaction between the substance and ions (atomic collisions) and neutrons (collisions with atomic nuclei).

Raman, infrared, and photoluminescent spectroscopy has been used to study changes in the surface structure of quartz diorite caused by friction. Before friction, the diorite surface layer has contained mainly quartz and feldspar crystals. After friction, some quartz and feldspar crystals have been destructed and replaced by a newly formed hydromica mineral with a low friction coefficient such as illite.

The structure of marble fracture fragments formed after the destruction under the action of a shock wave have been analyzed by Raman, infrared, and luminescence spectroscopic techniques. It has been found that calcite I in the surface layer of fragments with thicknesses of about 2 μm is transformed into high-pressure phase calcite III. At the same time, concentrations of Mn2+, Eu3+, and other ions decrease to about onefourth of their initial values.

Field-effect transistor (FET) structures based on soluble organometallic perovskites, CH3NH3PbBr3, were obtained and their electrical properties were studied. FETs made of CH3NH3PbBr3 films possess current- voltage characteristics (IVs) typical for ambipolar FETs with saturation regime. The transfer characteristics of FETs based on CH3NH3PbBr3 have an insignificant hysteresis and slightly depend on voltage at the source-drain. Mobilities of charge carriers (holes) calculated from IVs of FETs based on CH3NH3PbBr3 at 300 K in saturation and weak field regimes were ~5 and ~2 cm2/V s, respectively, whereas electron mobility is ~3 cm2/V s, which exceeds the mobility value ~1 cm2/V s obtained earlier for FETs based on CH3NH3PbI3.

Triboluminescence bursts are observed in two heterogeneous (diorite) specimens under friction against each other. Triboluminescence appears upon the relaxation of excited free ≡Si–O– radicals and Fe3+ ions and the capture of electrons with acceptor traps formed upon the destruction of the plagioclase crystal lattice. The analysis of the time dependence of these bursts shows that the friction surfaces accumulate clusters, in which the concentration of free ≡Si–O– radicals and electron traps is at least an order of magnitude higher than in their surrounding. The time interval between the appearance of two sequential clusters variates from 0.1 to 1 μs. The linear sizes of clusters are ~0.5 μm.

Luminescence spectra associated with calcite disintegration under the action of an electric-discharge-induced shock wave and under friction have been obtained. It has been found that, in these cases, the destruction mechanisms differ. Under the action of the wave, the crystal lattice of calcite decomposes into positively charged calcium, carbon, and oxygen ions. During friction, calcite disintegrates due to microcrack accumulation. The fraction of the volume that decomposes into ions depends on the electrical discharge energy. The percentage of decomposed calcite exceeds 60% when the energy is roughly equal to 80 J and is no higher than several fractions of a percent when the energy equals 0.2 J. In the latter case, disintegration localizes at grain boundaries, as follows from the time-resolved luminescence study (a time resolution of 2 ns).

On friction of a heterogeneous material: sandstone, flashes of triboluminescence are observed. Triboluminescence arises on the relaxation of excitation of free radicals ≡Si–O–. These radicals form on disruptions of Si–O–Si bonds and are located at microcrack edges. Microcracks form at the boundaries of feldspar and quartz microcrystals. Their sizes range from ~0.4 to ~7 μm. The microcrack formation on friction leads to the spalling of feldspar and quartz microcrystals from a sample.

The structure of surface layers of quartz sandstone with a thickness of ~1 μm before and after destruction by a compressive stress is studied by methods of infrared, photoluminescent, and Raman spectroscopy. Before destruction, this layer contained quartz grains cemented with montmorrillonite and kaolinite. The grains are covered with a thin water layer and have crystallographic defects: Si–O–, self-trapped excitons, AlOH and LiOH compounds, [AlO4]– centers, etc. The destructed surface contains separate quartz grains with sizes of ~2 μm and a reduced defect concentration. It is assumed that the defects reduce the strength of quartz grains, which are destroyed in the first turn.

The structure of surface layers with a thickness of ~1 μm formed at destruction of gneiss is studied by means of photoluminescent and infrared spectroscopy. It is found that, in this layer, feldspar (plagioclase and microcline) crystals are completely destroyed and replaced by montmorillonite.

It has been found that the friction of a heterogeneous material, namely, sandstone, leads to the appearance of triboluminescence. The phenomenon of triboluminescence corresponds to luminescence of ≡Si–O free radicals and Fe3+ ions. These radicals and ions are formed as a result of the breaking of Si–O–Si bonds in nanocrystals of quartz and feldspar entering into the composition of the sandstone. The time dependence of the triboluminescence intensity represents a set of flashes, each having the duration of a few nanoseconds. It has been assumed that triboluminescence flashes correspond to the appearances of cracks in the material. Сrack opening is found to be approximately 180 nm. The size distribution of the cracks is exponential.

The structure of a ~30 nm thick surface layer of a heterogeneous nanocrystalline solid body (sandstone) before and after the friction was investigated using photoluminescence and Raman spectroscopy. Before the friction, this layer contained nanocrystals of quartz, anatase, feldspar, and montmorillonite. The friction caused a sharp decrease in the concentration of nanocrystals of quartz and feldspar.

Samples of rocks with different physical properties (three kinds of granite, marble and quartzite) were subjected to destruction by impacts. Fractoluminescence was recorded on the damaged surface, and amplitudes and frequencies of series of light pulses were determined. On all test samples, initiation of intergrain cracks was observed. Defects on the surface of grains in granite samples had two typical sizes conformable with defects in quartz and spar, while uniform content minerals (marble and quartzite) features unimodal distribution of sizes of defects on the surface of grains.

Dynamics of microcrack formation and deformation of a granite-sample surface after a striker impact have been studied with a time resolution of 2 ns. The impact excites the sample’s natural vibrations that lead to formation of clusters of microcracks with linear dimensions of ~2 to 10 μm in feldspar grains. The formation of microcracks, in turn, excites natural vibrations of the grains.

Organic field-effect transistor (OFET) structures with the active layers on the basis of composite films of semiconductor polymer poly(3-hexylthiophene) (P3HT), fullerene derivatives [60]PCBM, [70]PCBM, and nickel (Ni) nanoparticles are obtained, and their optical, electrical, and photoelectrical properties are studied. It is shown that introducing Ni nanoparticles into P3HT: [60]PCBM and P3HT: [70]PCBM films leads to an increase in the absorption and to quenching of photoluminescence of the composite in the 400–600 nm spectral band due to the plasmon effect. In P3HT: [60]PCBM: Ni and P3HT: [70]PCBM: Ni OFET structures at the P3HT: [60]PCBM and P3HT: [70]PCBM concentrations of ~1: 1 and Ni concentrations of ~3–5 wt %, current–voltage (I–V) characteristics typical of ambipolar OFETs with the dominant hole conduction are observed. The charge-carrier (hole) mobilities calculated from the I–V characteristic at V G =–10 V were found to be ~0.46 cm2/(V s) for P3HT: [60]PCBM: Ni and ~4.7 cm2/(V s) for P3HT: [70]PCBM: Ni, which means that the mobility increases if [60]PCBM in the composition is replaced with [70]PCBM. The effect of light on the I–V characteristics of P3HT: [60]PCBM: Ni and P3HT: [70]PCBM: Ni OFETs is studied.

Structure is studied for diffusion layers of heat-resistant steel 16Kh2N3MFBAYu-Sh prepared by ion-plasma nitriding, and their phase composition is established represented by ultra-finely dispersed incoherent chromium nitride particles in a solid solution matrix. Contact fatigue strength of the nitrided layer prepared by an optimized regime is determined by experiment. A feature is established for the effect of nitride layer thickness on contact fatigue strength for heat-resistant steel alloyed with nickel. Nitriding regimes are recommended for treating low modulus gear wheels and other similar components whose performance is governed by contact fatigue strength.

The structure of two granite types (plagiogranite and alaskite) before and after shock wave action has been studied by infrared, Raman, and photoluminescence spectroscopy methods. It has been found that the shock wave caused transformation of quartz and feldspar crystals composing these granites into diaplectic glasses.

The vibrational—rotational spectrum of the HD16O molecule is studied within the range of 11200−12400 cm−1. The spectrum is recorded by an IFS-125M Fourier spectrometer with a resolution of 0.05 cm−1. The measurements are performed using a multipass White cell. A light-emitting diode is used as a radiation source. The signal-to-noise ratio was about 104. The centers, intensities, and half-widths of the spectral lines are determined by fitting to the experimental data by the least-squares method. A linelist containing more than 1500 lines is created. The results obtained are compared with the experimental data of other authors.

Stability of optical elements based on ZnS ceramics to dust and rain erosion is usually estimated from the loss of material mass in a directional flow of solid particles or atmospheric precipitates. In this case, the mechanism of degradation and fracture of the surface layer of an optical element is not considered. The photoluminescence (PL) method was used for investigating the crystal lattice response to the abrasive action and the formation of cleavage in ZnS ceramics, which differ in manufacturing technology and, accordingly, in the grain size by two orders of magnitude. It is shown that during abrasive treatment of samples, their spectra exhibit changes typical of degradation of the crystal lattice of material grains. The PL spectra of cleavage surfaces reveal almost complete degradation of the structure of crystallite grains with a size from 1–2 to 100–200 μm.

The method of luminescence with a time resolution of 2 ns has been applied to studying the dynamics of the surface destruction of uniaxially compressed granite by a shock wave caused by electric discharge in air near its surface. The shock impact causes emission of jets of positively charged ions from the most strongly distorted regions on the sample surface. It has been discovered that, when the compressing stress reaches ~0.92–0.95 times the sample’s breaking stress, two maxima can be observed on the time dependence of the jet intensity. The first maximum corresponds to the shock wave reaching the sample surface and the second maximum corresponds to the crack destroying the sample.

An electrical breakdown of the air near the surface of a compressed granite plate initiates a shock wave in it. Having reached the back side of the plate, the shock wave causes successive (with an interval of ~50 ns) emission of plasma jets presumably consisting of positively charged ions. The intensities of the jets are distributed exponentially. While the compression pressure P does not exceed ~0.9–0.95 of the failure pressure P f, it does not affect the number and efficiency of the radiation sources. At P ≈ (0.9–0.95)P f, the shock wave causes the emergence of a crack destructing the sample. Simultaneously, the number and efficiency of ion sources increase 3–4-fold. This phenomenon is explained by an increase in the concentration of clusters of dislocations upon the creep of the sample.

Laboratory modeling of the CRM formation on basaltic rocks from the Reykjanes submarine ridge and the Red Sea rift zone containing titanomagnetites (TM) with Tc ≈ 200 °C was carried out by annealing at different temperatures Tan for different time intervals up to 200-hour exposure in the external field BCRM = 50 μT. Monitoring the CRM value against annealing time revealed a strong correlation between the CRM intensity and a strong field magnetization Ms. The existence of this correlation implies that the process of CRM acquisition actually takes place only in a relatively short initial time interval of annealing, so that the further CRM changes in time basically follow variations of Ms due to the process of oxidation of TM taking place during the annealing. It is shown that at Tan = 350 and 400 °C TM grains are subjected to high degree of single-phase oxidation while annealing at high Tan = 450 and 500 °C leads to the oxyexsolution. The Arai-Nagata diagrams for samples bearing the isolated induced CRM can be approximated by two linear segments with a break point at T = (560–570) °C. For the low temperature interval (Tan, 560 °C), the calculated field Bcalc underestimates the true field BCRM by 33–56% at Tan = 350 and 400 °C but by 29–42% at Tan = 500 °C. Surprisingly, all specimens annealed at 450 °C yield Bcalc which is very close to the true field BCRM. The observed error in the determination of BCRM tends to decrease with increasing Tan probably due to the relative narrowness of the blocking temperature interval, centered near Tc.

The H2 16O vapor absorption line broadening by nitrogen pressure is investigated in the range of 12411–12421 cm −1 using a laser optoacoustic spectrometer with a Ti: sapphire laser having a lasing line width of 50 kHz. The broadening coefficients of 7 H2O lines determined by transitions to levels with the vibrational quantum numbers v = 4–8 are measured with an absorption sensitivity threshold of 10 −8 cm −1 . Experimental line half-widths are compared with their values calculated by the semi-empirical method.

Synthetic quartz single crystals are subjected to fracture by a falling load in the temperature range from 20 to 650°C (i.e., including the region of the α → β phase transition). The intensity of integrated acoustic emission (AE) generated during the impact is recorded in the frequency range from 80 kHz to 1 MHz. In the temperature range 20–300°C and at temperatures above the phase transition temperature (573°C), the energy distributions in temporal AE series are correctly described by the exponential function typical of random events, but at 400 and 500°C, the energy distributions follow the power law typical of correlated accumulation of microcracks in heterogeneous materials. The temperature effect is explained by the presence of submicrometer inclusions of a vapor—water mixture in the material, which exist as a rule in natural and synthetic quartz single crystals. Upon heating of the material to a certain critical temperature, the internal pressure in the bubbles of liquid attains a value for which the shock wave causes cracking around a large number of uniformly distributed inclusions. As a result, a correlated improper process of accumulation of microscopic defects, which is obviously observed only in heterogeneous materials, evolves in the bulk of deformed quartz heated to 400–500°C.