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Slip evacuation is shown for the first time to be applicable in the manufacture of large-size radio-technical parts from quartz ceramics. It was found that the evacuation of quartz glass based slip before molding ceramic blanks makes it possible to increase the density of the ceramic material by 0.01 g/cm3 and improve its uniformity by more than 30% and to reduce the number of cavities in parts made from quartz ceramic by removing air from the slip.

Materials with a near-zero refractive index open up new possibilities for enhancing nonlinear optical interactions. This lowers the threshold for nonlinear generation, reduces the size of existing nonlinear devices, and opens up prospects for new applications. In this work, the enhancement of stimulated Raman scattering (SRS) in materials with near-zero permittivity is studied. It is shown that the frequency shift of the Stokes wave gain is observed in these media, which leads to the shift of the SRS lines. In addition, a condition for the permittivity of the medium is obtained under which the SRS gain reaches its maximum value.

The effect of the pH and rotational mixing time of slip on the likelihood of the appearance of cracked rejects was determined by means of statistical analysis of data on the preparation of slip from quartz glass and data on ceramic rejects. By means of data on the zeta-potential of slip particles and an examination of the scheme of physicochemical transformations of submicron particles of quartz glass and silica sol in the slip we were able to identify the intervals of optimal values of the pH and rotational mixing time of the slip.

The effects of enhancement of stimulated Raman scattering in titanium oxynitride (TiON) nanofilms are considered. The mechanism of giant amplification of a Stokes wave is based on, first, localized plasmon resonance in titanium nitride (TiN) nanoparticles and, second, a spectrally degenerate behavior of the real part of the dielectric constant of the nanocomposite film. The enhancement of stimulated Raman scattering in the TiON film by means of a plasmonic nanoantenna and a nanostructured surface of the TiON film is demonstrated experimentally.

We analyze stimulated Raman scattering of a surface plasmon-polariton wave at the titanium nitride (TiN)/air interface. The increase of propagation length of the Stokes plasmon-polariton wave and its polarization rotation are shown.

The effect of plasticizers based on sulfonated melamine formaldehyde (Melment F 15 G) and polycarboxylate (Melflux 5581 F, Sika ViscoCrete-G2) on the properties of molding plaster consisting of α-calcium sulfate hemihydrate was studied. The concentrations of additives that increase the strength in compression of molding plaster samples by factor of 1.5 – 2 were determined on the basis of the results of this work.

The formation of very fine SiO2 particles during milling of quartz glass in the fabrication of ceramic parts was investigated. A method for determining the quantitative content of very fine silica in slip based on quartz glass was developed and tested. The concentration of very fine SiO2 particles in different batches of slip was determined. The influence of the content of the colloidal component in slurry on the sintering of ceramic material was evaluated.

The ion exchange selectivity of complex displacement chromatography (CDC) is analyzed. It is found that the separation factors determined by other means of complex chromatography, frontal and elution, are not always interchangeable with CDC. A way of determining the separation factors applied to CDC is proposed. A technique for constructing isotherms for the ion exchange of components to be separated with the simultaneous presence of displacer ions, hydrogen ions, and a sorbed complexone in the system is proposed as well. The change in the selectivity towards different valence elements is considered. For protonated complexes, the complete inversion of selectivity corresponds to the transition of the S-shaped separation isotherm from convex to concave. When protonated and binuclear М2А complexes are simultaneously present in a system, the inversion of selectivity is accompanied by mixed isotherms of variable type with two intersection points with a diagonal. The spreading of the displacement fronts is determined using the McCabe–Thiele approach. The lower part of the displacement front of the second component is spread in the case of a convex isotherm with an S-shaped pattern. For complex isotherms with two maxima, the center of the front is spread, while the lower and upper parts of the front are quite sharp.

Superlensing plays a crucial role in near- and far-field optical imaging with sub-wavelength resolution. One of the ways to expand optical bandwidth is surface plasmon resonances in layered metal-dielectric nanostructures. These resonances are commonly excited at a tunable single frequency. In this study, we propose the concept of a multimode far-field superlens made of a titanium oxynitride (TiON) thin film, that is a disordered metal-dielectric refractory nano-composite. These films exhibit a double epsilon-near-zero (2-ENZ) behavior near the percolation threshold and, therefore, favor super-coupling the incident laser light to surface plasmon resonances, not using such couplers as a prism, a grating, etc. We experimentally observe stimulated Raman gain emission from nano-structured TiON thin films exposed to low-power continuous-wave laser light. It is shown that superresolution of

Over the past decades, considerable progress has been made toward far-field optical imaging beyond the diffraction limit. However, most working proof-of-concepts are based on either time-consuming scanning of a subdiffraction focal spot over a sample or postrecovery treatment using a priori information on a sought image. To our knowledge, none of these can be regarded as being close to a perfect far-field superlensing system capable of real-time color imaging with subwavelength resolution. In this paper, we suggest a proof-of-concept for far-field nonlinear metalens that is made of a disordered metal–dielectric nanocomposite. Postoxidation of a refractory titanium nitride (TiN) thin film, used as a nonlinear plasmonic material, results in the formation of a titanium oxynitride (TiON) film comprising a mixture of multiple phases of TiOxNy. Due to a double epsilon-near-zero behavior near the percolation threshold, the TiON favors supercoupling of the incident light to surface plasmon resonance within the vi...

Emerging plasmonic materials are an essential driving factor of the ongoing progress towards the empowering of photonic devices functionalities and performance improvement. Transition metal nitrides, being refractory metals with tunable optical properties, are prominent representatives of alternative plasmonic materials. Recent intensive examination of linear and nonlinear optical parameters of metal nitrides has revealed TiN to be a promising media for metal-based optics. Another distinctive feature of TiN is its Raman activity. In contrast to Raman-silent metals, TiN-based structures enable nonlinear light frequency conversion not only to even and odd harmonics, but also to Raman-shifted modes. Moreover, the threshold of the underlying stimulated Raman scattering (SRS) effect in these structures could be greatly reduced by appropriate geometry and material design. Here we experimentally investigate the effect of structure and composition of TiN on its optical properties, such as dielectric permittivity and third-order Raman susceptibility. A special attention is given to synthesis and characterization of TiN thin films suitable for plasmon-assisted localization and amplification of optical signals.

Purpose : to evaluate the permeability of the scleral tissue for ultraviolet A (UVA). Materials and Methods. The study was conducted on 15 cadaver porcine eyes. Rectangular scleral flap 12*15 mm was cut out from each eyeball. The thickness of the sample was measured with a digital caliper. The outer surface of the scleral flap was irradiated with ultraviolet A. A sensor of the UV-radiometer was placed under the sample. It measured the UVA irradiance passing through the sclera. The absorption coefficient of ultraviolet A by the sclera was calculated from the formula derived from the Bouguer-Lambert Beer law: , where E 0 — the absorption coefficient, mm -1 ; — irradiance of the transmitted light, mW/cm 2 ; I 0 — irradiance of the received light, mW/cm 2 ; — thickness of the sclera, mm. Results . The absorption coefficient of ultraviolet A by the sclera was 4,91±0,43 mm -1 . According literature the threshold damaging radiation for retina is 7.7 J/cm 2 . Substituting these values in the converted formula of the Bouguer-Lambert-Beer law, we can derive an equation for calculating the threshold UVA irradiation dose of the sclera: , where 0 — the threshold UVA irradiation dose of the sclera, J/cm 2 ; — the base of the natural logarithm; — thickness of the sclera, mm. Conclusion. The absorption coefficient of ultraviolet A by the cadaver porcine sclera is 4,91±0,43 mm -1 . The derived formula of the threshold UVA irradiation dose of the sclera calculating allows to avoid the threatening for the retina procedure parameters in the performance of the scleral crosslinking with riboflavin/UVA.

Operation of a repetitively pulsed electric-discharge HF(DF) laser with an all-solid-state pump generator based on FID switches is demonstrated. The energy stored in the pump generator capacitors was 880 J at an open-circuit voltage of 240 kV and a discharge pulse repetition rate of 25 Hz. The specific energy extractions were 3.8 and 3.4 J L-1 for the HF and DF lasers, respectively. The possibilities of improving the output laser characteristics are discussed.

Alternative plasmonic materials are gaining more and more interest since they deliver a plethora of advantages in designing of optical metadevices. Among other alternatives, titanium nitride (TiN) has shown an exceptional combination of encouraging properties, such as CMOS- and bio-compatibility, high carrier concentration, tunability and outstanding robustness (high mechanical, chemical and temperature durability). Optical constants of TiN can be tuned at the synthesis stage. This allows for the adjustment of the spectral position of a plasmon resonance within the visible and near-infrared (NIR) range in order to match the desired working wavelength of a particular device. Together, these factors made TiN a popular material of choice in a diversity of recent plasmonic applications. Titanium oxynitride (TiON), which can be produced through the oxidation of TiN, have a great potential to build upon the success of TiN. Recently, it has been demonstrated that TiON thin films can exhibit a negative double-epsilon-near-zero (2ENZ) dielectric function. This unusual behavior of the permittivity opens up novel opportunities for the excitation of the plasmon resonance at several distinct frequencies within the visible and NIR region. Multi-resonant plasmonic components are beneficial for applications, where the enhanced light-matter interaction at multiple frequencies is demanded, such as nonlinear optics, up- and down-conversion, wavelength multiplexing and broadband absorption. This work begins with a brief survey of the recent progress in plasmonics made with TiN-based structures. Then we focus on TiON thin films with the 2ENZ behavior by discussing their potential in plasmonics. The experimental approaches useful for characterization of TiON thin films and the corresponding results are analyzed. These results are valuable for the development of 2ENZ plasmonic materials with large figure-of-merits in a diversity of applications. We believe that 2ENZ media is a powerful concept for multi-resonant plasmonics that will augment the functionalities and extend the operation bandwidth of plasmonic devices.

We consider a nonlinear mechanism of localized light inelastic scattering within nanopatterned plasmonic and Raman-active titanium nitride (TiN) thin films exposed to continuous-wave (cw) modest-power laser light. Owing to the strong third-order nonlinear interaction between optically excited broadband surface plasmons and localized Stokes and anti-Stokes waves, both stimulated and inverse Raman effects can be observed. We provide experimental evidence for coherent amplification of the localized Raman signals using a planar square-shaped refractory antenna.

The possibility of using lithium aluminosilicate glass crystallized in a low-temperature furnace (up to 1000°C) for manufacturing components for radio engineering purposes is studied.

Contemporary machining methods for ceramic materials are analyzed. Laser, hydroabrasive and high-speed machining are considered. The possibility of using these methods for machining large complexly-shaped ceramic objects having a double surface curvature is evaluated.

The mechanism of structure formation and phases formed in the course of synthesis of a glass ceramic lithium aluminosilicate system are analyzed.

Results are presented for a study of functional coating application, for example with increased blackness coefficient, on ceramic and glass ceramic materials. Various methods for coating application used currently are considered. A coating is proposed based on methyl phenyl spirocyloxane polymer (product MFSS-8).

The microstructure, phase composition, and mechanical properties of the alloy 44NKhTYu have been studied using metallography, X-ray diffraction, and acoustic testing. The main peculiarities of the formation of intermetallic phases and their effect on the mechanical properties of the alloy have been determined.

Existing ceramic technology is analyzed for producing high-speed zenith guided rocket antenna radomes made of glass ceramic OTM-357. This is the main production operations, and their disadvantages are noted. Prospects are considered for modernizing the technology.

Existing technology for manufacturing high-speed zenith guided rocket radomes from quartz and glass ceramic materials is analyzed. The main production operations are provided for this technology, their disadvantages are demonstrated, and ways of improving the quality of components are considered.

Three main materials are considered: sitall, high-alumina and quartz ceramic, currently used for creating rocket radomes. Physicotechnical properties of the materials are provided: thermal shock resistance, thermal conductivity, dielectric permittivity, dielectric loss tangent, and also stability during component operation.

Radioparent materials that exist in the world, that may be used in the production of the radome of high-speed zenith guided rocket fairings are analyzed. The main physicotechnical indices are provided for these materials and the future for their application in radome production is indicated.

The effect is considered of such operating properties as the design of a molding unit and the method of drying gypsum molds, on the life of the forming surface of molding units. Avoidance of the disadvantages revealed combined with results obtained in part 1 (E. I. Sudal’tsev, D. V. Kharitonov, and A. A. Anashkina, “Increase in the service life of forming surfaces of molding units. Part 1. Study of the improvement of molding unit forming surface material quality,” Novye Ogneupory, No. 2, 30 - 38 (2010).) of this work make it possible to increase the service life of molds by more than a factor of three

Materials are reviewed that are used in manufacturing the forming surfaces of molding units. Choice of the optimum water and gypsum ratio for a gypsum paste is provided and methods are considered for improving gypsum mold quality.

It is shown that one way of synthesizing new composite materials for producing antenna fairings may be the method of molding billets from mixed suspensions of lithium aluminosilicate and quartz glasses followed by sintering to the required level of physicotechnical properties. These studies make it possible to isolate a region of SiO 2 content (5-40%) within whose limits it is possible to prepare materials with quite high strength, i.e. from 75 to 120 MPa, and a broad spectrum of dielectric properties: a dielectric permittivity from 5.0 to 6.7, and a dielectric loss tangent from 0.009 to 0.007. It is established that the most uniform structure occurs for specimens molded from slips with a moderately fine SiO 2 addition (5-7% content of 63-500 μm particles) that promotes the minimum amount of open porosity in billets.

A method and a device are proposed providing continuous monitoring for assembly of ceramic billets. The suggested system makes it possible to monitor objectively fulfilment of the requirements of a production process that ultimately reduces scrap in preparing ceramic billets from aqueous slips.

Most important problems in modern photonics are fabrication, visualization and characterization of nanomaterials at optical frequencies. A number of optical techniques uses tightly focused laser beams to access longitudinal electromagnetic fields, which are directed towards the wave vector. In this Letter, the distribution of transverse and longitudinal optical fields in tightly focused laser beams, polarized in a new fashion, is investigated. Polarization dependent fingerprints of transverse and longitudinal optical fields are experimentally captured by means of photoinduced surface deformations in azobenzene polymer thin films.

An integrated study has been made on searching for new mold set designs and technological solutions to eliminate the effect of nonuniform buildup of ceramic preforms on the rejection rate. New molding equipment is proposed equipped with a molding monitoring system and an innovative centering device, which makes it possible to decrease the rejection rate in molding.

A solid-contact ion-selective electrode for thallium(III) based on its complex with new complexone N,N′-dioctylethylenediamine-N,N′-disuccinic acid ([Tl(DOEDDSA)]−) into a polymeric membrane is described. The ion-to-electron transducer used as the solid contact electrode was polyaniline which was electrochemically polymerized on a Pt wire. The plasticized poly(vinyl chloride) membrane incorporate ion-associate of [Tl(DOEDDSA)]− with N,N,N-trihexadecyl-N-methylammonium cation as electroactive material for ionometric sensor controls. The best performance in terms of slope (56±2 mV per decade) and response time (15 s) is displayed. The sensor shows a Nernstian response for [Tl(DOEDDSA)]− ions over a wide concentration range of 6.4×10−7 to 10−2 M, with a detection limit of thallium complexonate 8.2×10−8 M. The sensor can be used for more than three months without any considerable divergence in potentials. The selectivity is also good towards the most common univalent and divalent anions and the signal is constant in the pH range 4.7–9.0. An application to thallium determination in a mineral sample proved to be a success, and it was employed as an indicator electrode in direct potentiometry.

Basic methods for manufacture of large-sized complex-shaped ceramic components by casting from aqueous slips — cryogenic, centrifugal, electrophoretic, etc. — are considered. Of these, the slip casting in porous molds is advantageous in terms of cost and technological simplicity. To achieve further progress, attention should be focused on the development of adequate molding equipment to minimize the rejection rate of finished product.

Working materials for mold sets used in slip casting technology are reviewed. Benefits and shortcomings of the materials are discussed and routes towards improving their performance are suggested.

Traditional ceramic technology and an electrophoretic method for forming large-size complex-shaped preforms are discussed and compared. The superior of ceramic products prepared by the electrophoretic method is emphasized.

The results of a study of the processes of sintering and crystallization of Li-aluminosilicate glass ceramics have shown a route towards saving heat-treatment time (by a factor of 2.5 – 3.0) and power consumption without detriment to the major physicomechanical characteristics of the components produced.

An overview of the state-of-the-art in the use of technologies for electrophoretic shaping of ceramic materials from aqueous slips of inorganic materials is presented and a critical analysis of both strengths and limitations is given. The need for more efforts in the improved production of large-sized preforms with irregular profile using advanced electrophoretic deposition techniques is emphasized.

A brief review of the previous studies aimed at the development of techniques for fabrication of large-sized, thick-walled, complex-profiled ceramic components from aqueous slips of inorganic materials is given.

The effect of pre-heating on the phase composition of lithium aluminosilicate glass and glass ceramic is studied by the IR spectroscopy method. The results obtained provide a deeper insight into the kinetics of phase transformation in heat-treated materials and the temperature regime of crystal nucleation.

Factors involved in the mechanical grinding of odd-profiled pyroceramic components and their effect on the quality of product are discussed. Optimum conditions for tools, mechanical grinding regimes, schemes for grinding inner and outer surfaces of conical components, and fine finish of the surface to a required level are recommended.

Studies have been conducted showing that, for molding components from aqueous slips, the traditional casting technology based on the use of plaster molds can be replaced by a new technique of electrophoretic deposition. The new technique, using copper plates for both anode and cathode, saves processing time significantly (by several tens) and improves the quality of molded preforms.

The potential use of an electrophoretic deposition method for molding preforms from a lithium alumina-silicate slip is demonstrated. The time needed to mold preforms 20 mm thick does not exceed 100 min, and their physicomechanical properties (density, porosity of green and sintered materials, mechanical strength) compare well with those of preforms obtained by the traditional ceramic technology. Slips of finely dispersed grain composition can also be used to prepare glass ceramic parts with improved physicomechanical properties.

Methods for accelerating molding of large-sized thick-walled (dw = 16 – 20 mm) articles based on aqueous slip of inorganic materials (namely, quartz glass and lithium-aluminosilicate glass) are analyzed. The most promising is the method of electrophoretic molding of ceramics that shows good results in molding articles from quartz glass slip. The possibility of applying this method to ceramics based on lithium-aluminosilicate glass is yet to be investigated. The choice of material and design for the electrodes is another subject for investigation, since the authors have encountered the problem of articles sticking to the electrode surfaces.

First studies of the structure of the valence region in the conversion spectrum of the 1.56-keV (M1+E2) transition in 201Hg have been carried out. Physicochemical environment has been found to affect substantially the local electron density of impurity mercury atoms. The mechanisms responsible for the electronic-structure rearrangement are discussed.

The exact solution of the thermoelasticity problem obtained by the authors for a cylinder, one of whose end surfaces is heated while the other is cooled, is used for the first time to quantitatively describe the influence of the magnitude and direction of the heat flux on the contact thermal resistance. It is shown that appreciable macrowaviness of the original flat contacting surfaces can appear as a result of thermal expansion of the contacting samples when heat flows through the contact. Reversing the direction of the heat flux causes changes in the shape of the macrowaviness and in the contact thermal resistance.