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We report on the potential application of NIR–to–NIR Nd 3+ -doped yttrium vanadate nanoparticles with both emission and excitation operating within biological windows as thermal sensors in 123–873 K temperature range. It was demonstrated that thermal sensing could be based on three temperature dependent luminescence parameters: the luminescence intensity ratio, the spectral line position and the line bandwidth. Advantages and limitations of each sensing parameter as well as thermal sensitivity and thermal uncertainty were calculated and discussed. The influence of Nd 3+ doping concentration on the sensitivity of luminescent thermometers was also studied.

Glass formation in the As–Se–SbBr 3 system is studied. Glasses are synthesized by melting a batch of As, Se, and SbBr 3 at a temperature of 700°C. The density of the glasses and optical absorption in the IR region of the spectrum are measured. The glass transition and crystallization temperatures are determined using differential thermal analysis (DTA). The structure of the glasses is studied using Raman spectroscopy. It is proposed that antimony bromide enters the glass as isolated molecules, without exchanging bromine with arsenic selenide. The studied glasses are promising for the production of low-melting IR adhesives, lenses, and windows for various IR optoelectronic devices using the precise pressing method.

New glass compositions in the PbO-PbCl 2 -PbBr 2 system are synthesized and the region of vitrification is established. The temperature of sample vitrification is determined using the technique of differential-thermal analysis and the influence of the components on the temperature of vitrification has been studied. Infrared, Raman, and X-ray photoelectronic spectra are registered, suggestions about the glass structure are made, and the X-ray-phase analysis has been carried out. The density is measured and the refractive index of glass is estimated.

The local dissolution rates of chalcogenide films based on arsenic sulfide have been investigated in solutions of two types, i.e., alkaline aqueous solutions and amine solutions. The contribution of diffusion and hydrodynamic components to the total dissolution rate has been studied. It has been demonstrated that the possible contribution of the diffusion stages to the total rate of the interaction between the films and alkaline solutions is associated with the slow desorption of reaction products from the interface. The accumulation of interaction products in dipentylamine solutions favors an increase in the dissolution rate of the films, whereas the reaction products in the reaction with alkalis have an inhibiting effect. The difference between the used solvents of dipentylamine can lie in the difference between their abilities to form intermediate compounds with sulfur that have different nucleophilicities.

Some functions of the author's Mathematica 9 package are presented. Links are given to the author's interactive demonstrations. Mathematica supports 143 types of statistical distribution covering not only metrology but almost all statistical areas. The Supplement 1 to the ISO GUM mentions that analytical methods are ideal ones, but assume they are applicable only in simple cases, and recommends Monte Carlo method. In contrast, this paper presents Mathematica functions that can explore a multitude of methods in order to find analytical, numerical, or statistical results using (usually) one million random variates.

The change of the rate of dissolution upon the exposure of bilayer As 39 S 61 /As 36 S 44 Se 20 films to light of wavelength 380 nm and more than 470 nm from the sulfo-selenide layer side has been investigated. Although light of wavelength 380 nm is absorbed in the first layer, in the second layer photoinduced structural changes are observed, which are assumed to occur as a result of the diffusion of electron-hole pairs from the illuminated selenium-containing layer to the nonexposed arsenic sulfide in contact. The excess charge carriers induce structural changes in the As 39 S 61 film that are registered as dissolution rate changes. The calculated value of the drift mobility of the slowest charge carriers (electrons) of 10 −11 cm 2 /(V s) is in agreement with the literature data. Studies of the Raman spectra of the films of interest confirmed that the diffusion of excess electrons and holes into the sulfide layer resulted in structural changes that manifested themselves in a decrease in the intensities and widths of the bands corresponding to vibrations of structural groups containing homopolar bonds.

This work is devoted to the study of Eu 3+ -doped yttrium vanadate colloidal nanoparticles as possible thermal sensors. YVO 4 :Eu 3+ 6 at.% nanoparticles were synthesized by modified Pechini technique. The structural properties were studied with XRD, SEM, and SLS. XRD pattern indicates that nanocrystalline YVO 4 :Eu 3+ powders form only pure tetragonal phase without any impurities. SEM and SLS measurements reveal that average size of synthesized nanoparticles is 60 nm. Photoluminescence measurements show characteristic 4f–4f transitions of Eu 3+ ions upon 300 nm excitation. Relative intensities of Stark sublevels of 5 D 0 – 7 F 2 transitions demonstrate temperature dependence which enables ratiometric luminescence thermal sensing. The thermal sensitivity has been successfully calculated and compared to the previously reported nanothermometers.

This work is devoted to the study of Eu3+-doped yttrium vanadate colloidal nanoparticles as possible thermal sensors. YVO4:Eu3+ 6 at.% nanoparticles were synthesized by modified Pechini technique. The structural properties were studied with XRD, SEM, and SLS. XRD pattern indicates that nanocrystalline YVO4:Eu3+ powders form only pure tetragonal phase without any impurities. SEM and SLS measurements reveal that average size of synthesized nanoparticles is 60 nm. Photoluminescence measurements show characteristic 4f-4f transitions of Eu3+ ions upon 300 nm excitation. Relative intensities of Stark sublevels of 5D0-7F2 transitions demonstrate temperature dependence which enables ratiometric luminescence thermal sensing. The thermal sensitivity has been successfully calculated and compared to the previously reported nanothermometers.

Vitreous films in the Ga-Ge-S(Se) system are prepared through pulsed laser deposition and investigated. An analysis of the data of Raman and energy-dispersive X-ray spectroscopy demonstrates that the composition and structure of the films are similar to those of the monolithic glass. Exposure of the films to radiation with an energy higher than the band gap leads to bleaching of sulfur-based films due to the local oxidation of the films as judged from the data of infrared, Raman, and energy-dispersive X-ray spectroscopy. The replacement of sulfur by selenium in the composition of the films results in the opposite effect: irradiation of the films brings about the photoinduced darkening. Examination of the samples with the use of a scanning electron microscope does not reveal a substantial change in the morphology of the films under irradiation. The observed effect is used to write a copy of the diffraction grating with a resolution of 1200 grooves/mm.[PUBLICATION ABSTRACT]

Phase transformations upon crystallization of glasses in a magnesium-aluminosilicate system nucleated with TiO 2 as a nucleating agent, both doped and undoped with yttrium oxide, which were thermally treated in singleand two-stage modes in the temperature range 750–1200°C, have been investigated. Use of the two-stage mode with the first stage (nucleation) at 750°C yields changes in the phase composition and the temperature range of the existence of the metastable crystalline phases formed within the 800–1000°C range. At the highest thermal treatment temperature (1200°C), one observes crystallization of phases that are stable ones for this particular glass composition, irrespective of the existence of the nucleation stage. Doping with Y 2 O 3 significantly affects the character of liquid phase separation and crystallization through the increase of the temperature of formation of the first crystalline phases. There appear yttrium-containing phases—yttrium disilicate and titanate. The mechanism of the effect of yttrium oxide on the phase separation processes has been suggested.