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We present the calculated and the experimental mass spectra of alkali metal tungstates within the temperature range of 1100–1500 K and determine the vapor pressures and the thermodynamic properties of gaseous alkali metal tungstates.

The special aspects of spark plasma sintering (SPS) of plasma-chemical nanopowders of tungsten carbide with higher oxygen content were investigated. It was demonstrated that shrinkage rate of the WC nanopowders during SPS is limited by the rate of grain-boundary diffusion with the abnormally low values of activation energy. Decrease in the activation energy of SPS is caused by the influence of oxygen on the diffusion permeability of boundaries of the tungsten carbide grains at the stage of intense densification, as well as by abnormal grain growth. Kinetics of SPS of the WC-W2C-WO3-W nanopowder compositions at the stage of severe densification is controlled by the rate of sticking together the oxide particles, with their simultaneous transformation into W2C particles, and then by the plastic flow of W2C particles in the presence of the tungsten particles at the stage of high-temperature sintering. Ceramics with a high density ratio (98–99%) and ultra-fine-grained structure (the mean grain size less than 0.3 μm) with higher hardness HV = 30.5 GPa and fracture toughness of ~6.5 MPa m1/2 were obtained using the SPS method.

The effect of the carbon content on the kinetics of spark plasma sintering of nanopowder and submicron powder of WC–10% Co compositions was studied. Free carbon in the graphite form was introduced into nanopowders and submicron powders by mixing. The activation energy of solid-phase sintering at isothermal holding and continuous heating was determined. It is shown that increase in the carbon content leads to decrease in the volume fraction of the η phase and shift of the shrinkage curve into the region of low temperatures. It is established that an increase in the carbon content does not have a significant effect on the sintering activation energy of nanopowders and submicron powders in the region of “average” heating temperatures, the value of which is close to the activation energy of grain boundary diffusion in cobalt. It is shown that an increase in the carbon content leads to a significant decrease in the activation energy of consolidation of WC–Co powders in the region of “high” sintering temperatures owing to a decrease in the concentration of tungsten atoms in the γ phase based on cobalt. The sintering kinetics of fine-grained WC–Co alloys is limited by the rate of Coble diffusion creep of cobalt.

It is shown that the molecular composition of the vapor–gas phase of many chemical compounds and their mixtures, including carbides, nitrides, and oxides, is substantially more complex and diverse than it appeared before. In addition to monomeric molecules, various gaseous molecules of these compounds are detected in the vapors of carbides, nitrides, and oxides. Data on the composition of the vapors of nitrides of almost all the chemical elements from the periodic system as well as thermodynamic properties of gaseous nitrides are presented in this work.

Spark plasma sintering (SPS) of plasma-chemical nanopowders tungsten carbide with a high oxygen content are studied. The results show that the nanopowder WC shrinkages during SPS is limited by grain boundary diffusion with abnormally low activation energies. It is established that the decrease in the activation energy can be caused by the influence of oxygen on the diffusion permeability of the tungsten carbide grain boundaries at the stage of intense compaction, as well as by abnormal grain growth at the stage of high-temperature sintering. The SPS kinetics of WC-W2C-WO3-W nanopowder compositions at the stage of intense compaction is controlled by the rate of oxide particle sintering with their simultaneous transformation into W2C particles, and then, by the plastic flow of W2C particles in the presence of W particles at the stage of high-temperature sintering. Using the SPS method, we obtained ceramics with a high density (98-99%), ultrafine-grained structure (the average grain size is less than 0.3 mm), having an increased hardness HV = 30.5 GPa with a Palmquist crack resistance of ~6.5 MPa·m1/2.

Calculated and experimental mass spectra (at temperatures region of 1100-1500 K) of alkali metals tungstates are presented. Vapor pressures and thermodynamic characteristic of gaseous alkali metal tungstates are determined.

The effects of the conditions of a raw material introduction as well as mixing of it with a high-temperature gas flow under the plasma chemical synthesis of superdispersed powder of W–C have been studied. In the case of incomplete raw material evaporation and its fast quenching, preferred cubic tungsten carbide β-WC formation is found to occur, as well as nano- and microparticles with a complicated phase composition. In the case of complete raw material evaporation, the products of reducing synthesis are nanopowder of tungsten or semicarbide W2C depending on the amount of hydrocarbon introduced. There is a second stage of the process of low-temperature synthesis which leads to a single-phase of tungsten carbide α-WC formation. Complete evaporation of raw material must be ensured in the plasma chemical process for obtaining of α-WC powder with a maximum specific surface area.

Spheroidization of micropowders of a heat-resistant alloy based on nickel aluminide with a particle size of 20 to 45 μm was studied. The alloy was produced by calcium hydride reduction (CHR) and elemental synthesis (SHS). The spheroidization was carried out in a flow of argon–hydrogen thermal plasma generated by a direct-current (DC) plasma torch. The degree of spheroidization of the micropowders reached 98.5%, and the flowability was 20 s/50 g.

Experimental studies on the synthesis of aluminum oxynitride nanopowders in a reactor with a confined plasma jet by the interaction of disperse aluminum with ammonia and oxygen in a flow of nitrogen plasma generated in an electric arc plasma torch are performed. Preliminary calculations of the equilibrium compositions and thermodynamic characteristics of the multicomponent Al–O–N system are carried out. An optimal design of the reaction prechamber of the reactor is performed. Powders having a cubic structure and consisting of aluminum oxynitride phases with an average particle size in the range from 20 to 200 nm are obtained. It is established that the specific surface area of the obtained powders increases from 20 to 71 m2/g, and the nitrogen content in the nanopowders increases from 3.6 to 14.7 wt % with an increase in the flow rate of quenching gas from 1.8 to 6.0 m3/h. At the same time, the oxygen content decreases from 35.5 to 25.5 wt %. At a minimal flow rate of the quenching gas, the metallic aluminum and its oxide phases are present in the obtained powders. With an increase in the amount of quenching gas, the conditions for the mixing of aluminum vapors with oxygen and atomic nitrogen from decomposing ammonia are improved, which leads to the formation of aluminum oxynitride and aluminum nitride. The variation of the synthesis parameters allows us to obtain aluminum oxynitride nanopowders having a specific surface area ranging from 28 to 50 m2/g containing from 1 to 11 wt % of nitrogen and from 25 to 40 wt % of oxygen.

It is shown that powders of a model high alloy consisting of spherical particles 25–50 μm in size can be synthesized from a starting ultradispersed powder, which is made of a mixture of the alloy components and is fabricated by the magnesiothermal reduction of metal chlorides in the potassium chloride melt. The synthesis includes the stages of microgranulation of an ultradispersed powder, heat treatment of microgranules, classification of the microgranules with the separation of microgranule fraction of 25–50 μm, spheroidization of the separated fraction in a thermal plasma flow, and classification with the separation of a fraction of micro- and submicrometer-sized particles.

The formation of the WO3, SnO2 and ZnO metal oxide nanoparticles from vapors generated during evaporation of the material by a focused beam of microwave electromagnetic radiation with a frequency of 24 GHz and an energy flux density of more than 10 kW/cm2 is studied experimentally. The specific surface area of the nanopowders obtained over the entire range of the process parameters ranged from 1.9 to 8.3 m2/g, which corresponds to an average particle size of 430 to 95 nm. The possibility to control the dispersion composition of the powders is demonstrated. Increasing the quenching air flow increases the specific surface area of the powder obtained. The maximum evaporation rate of WO3 exceeded 100 g/h.

With the help of a complex of methods of disperse-structure analysis of nanopowders of plasmachemical synthesis, the function of particle-size distribution and its main characteristics—the average size and dispersion—are studied. A generalization of results of disperse characteristics for nanoparticles formed with the participation of various mechanisms—“vapor–solid” and “vapor–liquid–solid”—is carried out. It is shown that the formation of titanium nitride and carbonitride nanoparticles proceed on the vapor–solid mechanism without the participation of coagulative-particle growth. For the nanopowders under study, it is established that the variation range of standard deviation for the distribution function is in the interval of 30–60% of the average diameter; the index of aggregation is defined in the range of 1.5–3.0. It is revealed that the logarithmically normal function of particle-size distribution most authentically (with a correlation coefficient of more than 0.95) describes all studied objects for all mechanisms of particle formation in a wide range of dispersion of the received nanopowders independently of process parameters and organization of gas-disperse stream in the plasma reactor. Hypothetically, the established lognormal particle-size distribution is determined by the lognormal distribution of nanoparticles by residence time in the growth zone.

The synthesis of titanium nitride and carbonitride nanopowders from titanium tetrachloride vapor in a stream of hydrogen–nitrogen plasma, generated by an arc torch, in confined-jet flow reactor has been experimentally studied. Single-phase nanopowders with a NaCl-type cubic crystal lattice as assemblies of preferably cube-shaped nanoparticles of a 20–150 nm size and aggregates based on them have been obtained in the experiments. By varying the synthesis parameters, it has been possible to prepare titanium nitride nanopowders with a specific surface area in the range of 11–39 m2/g containing 18.8–22.5 wt % nitrogen, which corresponds to the empirical formula TiN0.79–TiN0.99. The titanium carbonitride nanopowders had a specific surface area of 13–23 m2/g and carbon and nitrogen contents of 7.5–13.6 and 13.5–5.1 wt %, respectively.

Equilibrium energy and technological characteristics of the plasma synthesis of titanium nitride, carbide, and carbonitride, in particular, the composition and yields of final products, energy consumption upon their production, and the required enthalpy of a plasma flow, are calculated for the following reactions: TiCl4 + xH2 + yN2 (synthesis of TiN), TiCl4 + xH2 + zCmHn (synthesis of TiC), and TiCl4 + xH2 + y1N2 + z1CmHn (synthesis of TiCN). The calculations are carried out for the temperature range from 500 to 4000 K, at the total pressure of 0.1 MPa in the system, and with the following molar ratios of reagents: x = 8, x = 20; y = 0.5, y = 5, y = 20; z = 0.9, z = 1.0, z = 1.1; y1 = 5; z1 = 0.4, z1 = 0.5, z1 = 0.6.

The characteristics of heat and mass transfer to the wall of a confined-jet plasma flow reactor on the basis of an electric arc plasmatron in the processes of nanopowder preparation from metals and their compounds are studied experimentally. Nanopowders are prepared from copper, tungsten, aluminum oxide, and a composition based on tungsten carbides. The heat flow distribution and the distribution of the mass flow of nanoparticles to the reactor surface at different parameters of the nanopowder preparation processes are studied.

Experimental studies on the synthesis of aluminum oxynitride nanopowders in a reactor with a confined plasma jet by the interaction of disperse aluminum with ammonia and oxygen in a flow of nitrogen plasma generated in an electric arc plasma torch are performed. Preliminary calculations of the equilibrium compositions and thermodynamic characteristics of the multicomponent Al–O–N system are carried out.

The synthesis of titanium nitride, carbonitride, and carbide nanopowders from titanium tetrachloride vapor in the stream of hydrogen or hydrogen–nitrogen plasma, generated by an electroarc torch, in a confined-jet flow reactor has been experimentally studied. Single-phase nanopowders with a NaCl-type cubic crystal lattice as assemblies of preferably cube-shaped nanoparticles of a 20–150 nm size and aggregates based on them have been obtained in the experiments. By varying the synthesis parameters, it has been possible to prepare titanium nitride nanopowders with a specific surface area in the range of 11–39 m2/g containing 18.8–22.5 wt% nitrogen, which corresponds to the empirical formula TiN0.79–TiN0.99. The titanium carbonitride nanopowders had a specific surface area of 13–23 m2/g, carbon and nitrogen contents of 7.5–13.6 and 13.5–5.1 wt%, respectively. The titanium carbide nanopowders had a specific surface area of 14–45 m2/g and carbon contents of 17–21 wt%. Most reached yield of main products was 94%.

ZrO2, ZrO2–MgO, and ZrO2–Al2O3 nanopowders are obtained via oxidation of disperse ZrCl4 and its blends with (Mg, Al) metals by oxygen in a plasma reactor with confined plasma jet flow on the basis of an dc arc plasma generator. The change in the ZrCl4 rate and plasma jet enthalpy allows one to synthesize nanopowders with the specific surface area of 18–32 m2/g (Dav = 33–58 nm). The obtained nanopowders are polydisperse, consist of uniaxial spherical particles, and contain 0.25–0.75 wt % of chlorine. The dependence of the chlorine content in powders on the zirconium chloride output exhibits an extreme behavior. The ZrO2 nanopowders represent a mixture of monoclinic and tetragonal zirconium dioxide modifications with approximately equal contents. The ZrO2–MgO nanopowders (10 mol %) with the cubic structure identified as Zr0.875Mg0.125O1.875 are obtained in oxidation of the ZrCl4–Mg mixture in an oxygen–argon plasma stream. The ZrO2–Al2O3 nanopowders (30 wt %) are synthesized by oxidation of the ZrCl4–Al blend, whose phase composition is represented by tetragonal ZrO2 structure with monoclinic phase impurity in the absence of any Al2O3 phases, which can be explained by the formation of nonequilibrium Zr–Al–O solid solution with tetragonal structure as a result of the size effect.

Fabrication of WO3 tungsten oxide nanoparticles by evaporation of the initial oxide material with a focused beam of 24-GHz electromagnetic radiation generated in a 5-kW gyrotron complex at a design microwave power density of 10 kW/cm2 has been experimentally studied. Tungsten oxide powders consisting of particles, which sizes are in range of 20 nm up to 1 μm, have been obtained. The particles have different shapes, close to spherical or octahedral, suggesting their formation via both the “vapor-liquid-crystal” and the “vapor-crystal” mechanism. The maximal evaporation rate was 100 g/h. The feasibility of powder dispersity controlling by varying the flow rate of cooling air has been revealed.

The structure and properties of Fe and Ni3Al weld metals doped with TiCN and WC nanoparticles are investigated via optical and scanning electron microscopy, X-ray spectroscopic microanalysis, and fatigue life and abrasive wear tests.

Results of investigation of the incorporation of zirconia and silica nanoparticles into the coatings formed on magnesium alloy by plasma electrolytic oxidation are presented. Comprehensive research of electrochemical and mechanical properties of obtained coatings was carried out. It was established that the polarization resistance of the samples with a coating containing zirconia nanoparticles is two times higher than that for the sample with base PEO layer. One of the important reasons for improving the protective properties of coatings formed in electrolytes containing nanoparticles consists in enhanced morphological characteristics, in particular, the porosity decrease and increase of thickness and resistivity (up to two orders of magnitude for ZrO2-containing coating) of porousless sublayer in comparison with base PEO layer. Incorporation of silica and zirconia particles into the coating increases the mechanical performances. The layers containing nanoparticles have greater hardness and are more wear resistant in comparison with the coatings formed in the base electrolyte.

The synthesis of TiN nanopowder from titanium hydride in thermal plasma generated in DC arc plasmatron is investigated experimentally. It is shown that a single-phase TiN nanopowder can be produced within a two-stage process consisting of plasma synthesis and separation of powdered product by means of sedimentation. The yield of nanopowder is up to 90%.

The structure of a welded joint obtained by argon-arc welding with the use of a composite electrode wire of a Ni3Al-base alloy after directed crystallization is studied. It is shown that the use of composite electrode wire containing nanoparticles of tungsten carbide for argon-arc welding promotes formation of a quality weld metal and a defect-free transition zone between the latter and the directedly crystallized alloy based on Ni3Al.

The possibility of pyrometallurgical processing of a loparite concentrate at a temperature of 2000–4000 K and a pressure of 0.1 MPa is thermodynamically studied using the TERRA software package. It is found that the niobium concentration in the concentrate almost doubles during plasma heating as a result of thermal decomposition and the precipitation of rare-earth metals into a gas phase. Crude niobium can be extracted from the thermally decomposed concentrate by carbothermic or aluminothermic reduction. After plasma-arc vacuum refining, crude niobium can be used for making commercial ferroniobium. The calculated energy consumed for the plasma production of ferroniobium from the loparite concentrate by carbothermic or aluminothermic reduction under adiabatic conditions is 46.6 or 79.0 GJ/(t ferroniobium), respectively. The energy consumption can even be increased severalfold, and the implementation of the process remains economically efficient at the existing market price of ferroniobium.

The thermodynamics of reduction of titanium magnetite (Fe oxides >70%, Ti oxides >9%) with carbon and methane at temperatures of 1500–3000 K is considered. The results of the experimental study of plasma-arc liquid-phase reduction of the concentrate from the Gremyakha-Vyrmes deposit are presented. The possibility of obtaining naturally alloyed metal with both low and high concentration of alloying elements, vanadium and titanium included, is demonstrated.

The formation of layers of copper and tungsten nanoparticles on the surface streamlined by a flow of products of plasma synthesis in a confined-jet flow reactor has been investigated. The distribution of heat and mass fluxes onto the surface of the plasma reactor has been studied for various values of the enthalpy, thermal-plasma flow velocity, and reactant concentrations.

The magnetic properties of the coatings formed by plasma electrolytic oxidation on titanium and modified by nanoparticles of cobalt were studied. The coercitivity of the obtained magnetoactive layer were equal to 514 Oe at room temperature and to 1024 Oe at 2 K. The high coercitivity is the result of the nanosize effects of particles embedded in the coating. The structure of the nanoparticles, which consist of a Co ferromagnetic core and a CoO antiferromagnetic shell, determines the magnetic properties of the coatings on the whole.

The prospects of using organic and inorganic nanosized materials are shown in the process of the formation of surface multifunctional composite protective layers obtained using plasma electrolytic oxidation on metals and alloys.

Thermodynamic analysis of steady state conditions of the “concentrate (titaniferous magnetite)—reducing agent (carbon)” system is carried out for different temperatures and concentrate/agent mass ratios. A pilot setup for experimental research of the process of plasma liquid-phase carbothermic reduction of Fe-Ti concentrate is developed. The possibility of plasma-arc metal recovery from titaniferous magnetite concentrates with almost full separation of metallic and oxide phases is demonstrated.

We describe methods and instrumentation that we have developed for measuring the radiance distribution over the emitting region of plasma emitters in the extreme vacuum ultraviolet region. The radiance comparator for vacuum and near ultraviolet radiation includes a reflecting telescope based on highly reflective nanostructures, a set of filters to eliminate the effect of scattered light and higher orders of diffraction, and a cooled CCD array.

The generation of atoms and radicals by the equilibrium thermal dissociation of oxygen and the same process involving water vapor are similar in terms of the reactive-species yield and energy consumption. The energy input into the generation of atoms and radicals is the smallest at 4500 K; about 70% of the energy is spent directly for the breaking of chemical bonds. From the calculations of the kinetics of oxygen atom recombination, it follows that cooling at a rate higher than 107 K/s makes it possible to achieve considerable deviations from the equilibrium atom concentration. The lifetime of atoms in cooling thermal plasma is estimated at 10−5 s. It has been established experimentally that a thermal plasma jet plunging into the water bulk generates hydrogen peroxide. The totality of factors affecting the hydrogen peroxide accumulation rate can be represented in as a generalized parameter, specifically, the atomic oxygen feed rate.

High-temperature mass-spectrometric analysis is used to study the evaporation of SrWO4 (J) at 1805–1890 K. SrWO4 (g) molecules are found to be present in the vapor. The pressure of the SrWO4 (g) molecule vapor is determined to be logP = −25052/T + 7.13. The heat of sublimation (ΔH° s, 0 (SrWO4(s)) = 620 ± 20 kJ/mol) is determined using the third law of thermodynamics. The atomization energy of the SrWO4 (g) molecules is calculated to be ΔH° at, 0 (SrWO4 (g)) = 3030 ± 40 kJ/mol.

The new method for metal oxide nanopowder production is proposed. It is the evaporation–condensation using a focused microwave radiation. The source of microwaves is technological gyrotron with frequency of 24 GHz and power up to 7 kW with the energy density flux of 13 kW/cm2. Radiation was focused on the layer of powder of the treated material to ensure its evaporation, subsequent condensation of vapor in the gas stream, and deposition of particles on the water-cooled surface. Deposited powders consist of particles whose sizes are in the range of 20 nm to 1 μm. The powder consists of particles having different shapes—close to spherical shape as well as octahedral, which indicates that the mechanism of particles formation is “vapor–liquid–crystal” as well as “vapor–crystal.” The maximum evaporation rate was 100 g/hr. The proposed approach is original and extends the possible methods of producing nanoparticles.

Theoretical analysis is given to one of the promising processes for the preparation of nanosized metal powders, namely, plasma chemical synthesis by the action of thermal plasma on a material distributed in the plasma. Special attention is given to the methodology of investigation of such plasma jet processes, which may ensure the prediction of results of experimental studies; qualified data processing; and, ultimately, preparation of powders with a prescribed composition and required nanoscale dimensions by means of controlled plasma-chemical synthesis.

Current state, problems and prospects of plasma metallurgy are discussed. Investiga- tions of the author and other scientists worked mainly in the former Soviet Union in the field of plasma processes theory and practice are the base for the paper. A number of examples are given of successful practical application ensuring increase of productivity and improvement of ecological condition, saving of resources and energy and formation of products with specific properties. Special attention is given to the problem of energy and metallurgical complexes development on the basis of plasma technology.

High-temperature mass-spectrometric analysis is used to study the sublimation of SrMoO4(s) at 1570–1800 K. SrMoO4(g) molecules are found to be present in the vapor. The vapor pressure of the SrMoO4(g) molecule is determined to be log p = −19980/T + 7.99. The heat of sublimation ΔHs, 0o (SrMoO4(s)) = 480 ± 40 kJ/mol is determined using the third law of thermodynamics. The atomization energy of the SrMoO4(g) molecules is calculated to be ΔHat, 0o (SrMoO4(g)) = 2860 ± 40 kJ/mol.

The sublimation of CaMoO4(s) is studied by high-temperature mass spectrometry at 1530–1770 K. CaMoO4(g) and MoO3(g) molecules are found to be present in the vapor; their vapor pressure is determined. The pressure of the CaMoO4(g) molecule vapor is determined to be logp = − 19 685/T + 5.52. The heat of sublimation ΔH s, 0 o (CaMoO4(s)) = 446 ± 40 kJ/mol has been determined using the third law of thermodynamics. The atomization energy of the CaMoO4(g) molecules is calculated to be ΔH at, 0 o (CaMoO4(g)) = 2910 ± 40 kJ/mol.

A linear two-frequency cw Nd3+ : YAG laser, pumped by a laser diode, emitted the λ = 1.06 mm wavelength. Stable generation of two linear orthogonally polarised axial modes was achieved for mode spacings ranging from 5 MHz to ~ 9 GHz.

The blocking potency of P- and L-selectin was studied for certain small molecule mannosides and their polyacrylamide (PAA, 30 kDa) conjugates in comparison to SiaLex and fucoidan. Two experimental systems were used: (1) solid phase static assay based on recombinant selectins, and (2) P-selectin dependent rat peritoneal inflammation. βMan-SC6H4NO2-p was four times more potent P-selectin inhibitor as compared to SiaLex. Docking of this molecule onto the P-selectin carbohydrate-binding site demonstrated that a nitro group enabled an electrostatic interaction with residue Lys 84, while the phenyl ring and the CH2 at C-6 contacted the CH2 groups of the same Lys residue. In vivo, βMan-SC6H4NO2-p blocked experimental inflammation better than SiaLex, but significantly lower than fucoidan. In vitro Man-polyacrylic acid conjugates appeared to be very potent inhibitors comparable to fucoidan, uncharged Man-PAA proved rather active, comparable to SiaLex-PAA both in vitro, and in vivo, whereas mannan did not display any P-selectin blocking effect. Published in 2004.

Single-frequency lasing with an output power up to 8 mW was achieved using a neodymium-activated YAG crystal with a resonator length 3.5 cm. This crystal was pumped by a semiconductor laser. Mode selection and tuning of longitudinal modes within an interval of 1 cm−1 were performed by a thin-film Troitskoĭ selector.

A compact source of coherent ultraviolet radiation was constructed from a YAG:Nd3+ laser pumped by semiconductor laser diodes. The average output power at λ = 266 nm was 1.1 mW when the electrical pump power was 6.4 W. The duration of the output pulses was 5 ns, the power carried by them was 37 W, and the repetition frequency was 6 kHz.

The results are presented of theoretical and experimental investigations of room-temperature YAG:Nd lasers pumped by light-emitting diodes. The lasing characteristics of a laser operated at the 1.06 and 1.32 µ wavelengths were investigated in the cw and pulsed regimes and dependences of its parameters on the temperature, pulse repetition frequency, and other factors were studied. In the pulsed regime the laser efficiency was 0.2% and in the cw regime the radiation power reached 50 and 17 mW at the 1.06 and 1.32 µ wavelengths, respectively.

Theoretical and experimental investigations were made of intracavity second harmonic generation (SHG) using radiation from semiconductor-pumped cw solid-state lasers. When YAG:Nd3+ was pumped by radiation from arrays of light-emitting diodes, the cw single-mode output power at λ = 1.06 and 1.32 µ was 120 and 100 mW, respectively, and the radiation power at λ = 0.53 µ was 30 mW. The experimental results were in good agreement with the calculations. The maximum multimode powers at λ = 1.06 and 0.53 µ were 220 and 50 mW. An analysis was made of the results of a study of SHG of radiation from a lithium neodymium tetraphosphate laser pumped by a single injection laser. It was found that intracavity SHG in semiconductor-pumped lasers can improve the efficiency by one or two orders of magnitude, can reduce the mass, size, and specific consumption of materials, and can substantially increase the useful life of lasers emitting in the green part of the spectrum.