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Multicomponent equimolar perovskite oxides (ME-POs) have recently emerged as a highly promising class of materials with unique synergistic effects, making them well-suited for applications in such areas as photovoltaics and micro- and nanoelectronics. High-entropy perovskite oxide thin film in the (Gd0.2Nd0.2La0.2Sm0.2Y0.2)CoO3 (RECO, where RE = Gd0.2Nd0.2La0.2Sm0.2Y0.2, C = Co, and O = O3) system was synthesized via pulsed laser deposition. The crystalline growth in an amorphous fused quartz substrate and single-phase composition of the synthesized film was confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Surface conductivity and activation energy were determined using a novel technique implementing atomic force microscopy (AFM) in combination with current mapping. The optoelectronic properties of the deposited RECO thin film were characterized using UV/VIS spectroscopy. The energy gap and nature of optical transitions were calculated using the Inverse Logarithmic Derivative (ILD) and four-point resistance method, suggesting direct allowed transitions with altered dispersions. The narrow energy gap of RECO, along with its relatively high absorption properties in the visible spectrum, positions it as a promising candidate for further exploration in the domains of low-energy infrared optics and electrocatalysis.

Magnetorheological polishing is a critical method for ultra-precision machining of fused quartz glass. The selection of process parameters significantly impacts machining efficiency. To fully study the effect of magnetorheological polishing on the processing efficiency of fused quartz glass, a mathematical prediction model must be established. Therefore, a material removal rate model based on the extended Preston equation is proposed to predict material removal during magnetorheological polishing. The model incorporates factors such as workpiece rotation speed, polishing disc rotation speed, polishing gap, and correction factor. Experimental results show that the theoretical calculations align well with experimental results. The maximum average error is 8.97%, which verifies the accuracy of the established model. Additionally, the material removal rate decreases with increasing polishing gap. It increases with the increase in the rotation speed of the workpiece and the polishing disc. When the polishing gap is 2 mm, the workpiece rotation speed is 350r/min, and the polishing disc rotation speed is 400r/min, the maximum surface roughness is reduced from 148 nm to nearly 4 nm. This study enables precise prediction of the deterministic removal amount during magnetorheological polishing of fused quartz glass. It provides a theoretical basis for the selection of polishing process of fused quartz glass.

Mixed seeds of fused quartz particles and silicon particles were laid at the bottom of the crucible to assist the growth of multicrystalline silicon crystals. The full melting process was used, and then we found that the grown crystals had higher quality. The effect of mixed seeds on the growth of multicrystalline silicon was studied. The results showed that fine and uniform initial grains could be obtained by mixed seeds assisting the growth of crystals. Increasing the number of grain boundaries can better release thermal stress and inhibit the proliferation and diffusion of dislocations. The defect density of multicrystalline silicon decreased and the minority carrier lifetime increased, thus improving the conversion efficiency of multicrystalline silicon cells.

This study advances glass nanocomposite research by achieving exceptional Electromagnetic Interference (EMI) shielding while maintaining optical transparency. We employ femtosecond laser engraving and thermal vapor deposition to create precise periodic line patterns on fused quartz glass, which serve as a framework for the controlled deposition of silver (Ag) and gold (Au) nanoparticles through laser-ablated micro-channels. These nanocomposites effectively balance EMI shielding and optical transmittance, making them suitable for applications in electronics, aerospace, and telecommunications. Femtosecond laser ablation allows for meticulous glass surface modification. Using an XY motorized translation stage guided by a photoresist, we form line patterns with spacings of 200, 400, and 600 µ-meter, resulting in Shielding Effectiveness (SE) in the range of 10–37 dB. Notably, despite substantial modification, the glass nanocomposites retain optical transmittance comparable to clear glass, enhancing their utility in applications where visual clarity is essential, such as windows, displays, and security infrastructure. By integrating femtosecond laser ablation with controlled thermal deposition, we produce multifunctional glass nanocomposites that offer promising EMI shielding and optical transparency, paving the way for advanced materials in industries where both properties are critical.

Large-aperture fused silica phase optical components such as continuous phase plate (CPP) are widely used in large-scale laser devices to achieve beam homogenization and improve beam quality. However, under the action of high-energy lasers, their lower damage threshold seriously restricts their service life and increases cost of using. Compared with other fused silica components, chemical processing technology with hydrofluoric acid solution (HF) is lacking in the processing of phase components because the residual root mean square value (RMS) of phase elements is very high, and it can not guarantee this. Therefore, it is necessary to carry out research on the influence of chemical treatment on phase components. In this paper, we improved the chemical treatment process to achieve the change of residual RMS value not more than 3 nm, and improved the ability of resisting laser damage that the damage threshold of 29J/cm 2 was obtained under the test conditions 351nm@3ns. Finally, we successfully mastered the chemical control process of phase components and applied it to the CPPs as other fused quartz materials engineering production process.

The paper analyzes numerically the hydrodynamic processes developing inside the fused quartz under the action of intense laser impulses. Depending on laser intensity two basic regimes are obtained and described in details. At low intensities, the slow regime driven by the heat transfer is observed. Herewith, the fracture took place in the heated region before the phase transition. At higher intensities, the high-speed propagation regime is established characterized by the fracture events exactly at the interfacial boundary between the hot plasma and condensed phase. The propagation of absorption wave coupled with the fracture wave is limited by the value of sound speed in the hot plasma, which determines the expansion of plasma into the spallation region ahead of the absorption front. The proposed model of the process agrees well with the recent experimental data, in particular with the characteristic velocity scales.

A method is described to measure the thermal expansion coefficient of fused quartz glass. The measurement principle is to monitor the change in resonance frequency of a Fabry–Perot cavity as its temperature changes; the Fabry–Perot cavity is made from fused quartz glass. The standard uncertainty in the measurement was less than 0.6  ( nm · m - 1 ) · K - 1 , or 0.15 %. The limit on performance is arguably uncertainty in the reflection phase-shift temperature dependence, because neither thermooptic nor thermal expansion coefficients of thin-film coatings are reliably known. However, several other uncertainty contributors are at the same level of magnitude, and so any improvement in performance would entail significant effort. Furthermore, measurements of three different samples revealed that material inhomogeneity leads to differences in the effective thermal expansion coefficient of fused quartz; inhomogeneity in thermal expansion among samples is 24 times larger than the measurement uncertainty in a single sample.

More and more researchers are studying the heat transfer performance of aeronautical materials at high temperatures. In this paper, we use a quartz lamp to irradiate fused quartz ceramic materials, and the sample surface temperature and heat flux distribution were obtained at a heating power of 45~150 kW. Furthermore, the heat transfer properties of the material were analyzed using a finite element method and the effect of surface heat flow on the internal temperature field was investigated. The results show that the fiber skeleton structure has a significant effect on the thermal insulation performance of fiber-reinforced fused quartz ceramics and the longitudinal heat transfer along the rod fiber skeleton is slower. As time passes, the surface temperature distribution tends to stability and reaches an equilibrium state. The surface temperature of fused quartz ceramic increases with the increase in the radiant heat flux of the quartz lamp array. When the input power is 5 kW, the maximum surface temperature of the sample can reach 1153 °C. However, the non-uniformity of the sample surface temperature also increases, reaching a maximum uncertainty of 12.28%. The research in this paper provides important theoretical guidance for the heat insulation design of ultra-high acoustic velocity aircraft.

In this paper, a quasi‐optical resonator with new coupling method and parasitic‐mode‐suppressing in 110–170 GHz is proposed. The coupling of terahertz (THz) quasi‐optical resonator in this paper is realized by PCB substrate processing and pressurized flange. At the same time, the parasitic mode is effectively suppressed by slitting the plane mirror to reduce the influence on the main mode during the test. And the fused quartz sample was tested to verify the feasibility of the system for complex dielectric testing of materials in 110–170 GHz. In this paper, a quasi‐optical resonator with new coupling method and parasitic‐mode‐suppressing in 110–170 GHz is proposed. The coupling of terahertz (THz) quasi‐optical resonator in this paper is realized by PCB substrate processing and pressurized flange. At the same time, the parasitic mode is effectively suppressed by slitting the plane mirror to reduce the influence on the main mode during the test. And the fused quartz sample was tested to verify the feasibility of the system for complex dielectric testing of materials in 110–170 GHz.

A set of experimental data on the thermodynamic parameters of polymorphic transitions in the silica system is considered. Analysis of these parameters in dimensionless form is performed. A fundamental result of the analysis is that the thermodynamic parameters of all silica polymorphs after transitions are described by a single universal Hugoniot of polymorphic transition. It is shown that the two-shock model of polymorphic transformations proposed earlier by the author describes all the results obtained in the analysis. A joint consideration of the experimental data and model calculations leads to the conclusion that during a polymorphic transformation, the density of the new phase is determined from the condition that the elastic pressure components after the first shock and after the polymorphic transition are equal.