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Methods for trapping the C in waste gases by means of a combined technology are examined. The wastes gases from pyrochemical production can be purified by removing C by passing the gases at rates to 5 m/h through a 0.5 m high layer of Ba(OH)·8HO granules in a 0.14 m in diameter apparatus after dilution with atmospheric air. The purification of the waste gases from hydrometallurgical production by removal of C (50 m/h) is best accomplished by passage through a 0.28 m in diameter packed tower with 2.7-4 m high packing irrigated by an alkali solution which is regenerated by means of calcium hydroxide. The waste gases from pyrochemical production can also be passed through a packed tower. In this case the C is fixed in insoluble calcium carbonate and is placed in a storage facility and subsequently buried. The proposed technologies make it possible to purify the waste gases formed during the reprocessing of spent uraniumplutonium nitride nuclear fuel in a reprocessing module used in an on-site nuclear fuel cycle by removing C to a level admissible for air in production enclosures. [ABSTRACT FROM AUTHOR]

The Sn – As – P system is characterized by the presence of unlimited solid solutions (Sn4As3)x (Sn4P3) 1–х (α-phase) and solid solutions based on tin monoarsenide (β-solid solutions) and SnP3 phosphide (γ-solid solutions). The solubility of phosphorus in SnAs depends not only on temperature, but also on the direction of the polythermal cross section, i.e. from that in the form of an individual simple substance or in the form of any of the tin phosphides, the doping component is introduced. In the present work, the confi guration of the region of existence of solid solutions of phosphorus in tin monoarsenide was investigated. Alloys of SnAs – Sn4P3:SnAs – Sn0.43P0.57; SnAs – SnP3 and SnAs – P polythermal sections, annealed at 753 K, were studied by X-ray phase analysis, the concentration range of the existence of a homogeneous solid solution was established, the parameters of the crystal structure were determined. The construction of quasi-chemical schemes for the doping of tin monoarsenide showed that with the introduction of SnP3, the greatest deviation from stoichiometry towards the lack of tin is observed. The highest solubility of phosphorus, reaching 30 mol % corresponds to this cut. Thus, the region of existence of solid solutions based on tin monoarsenide has an asymmetric shape shifted toward an excess of volatile components, and the maximum solubility of phosphorus corresponds to the direction of the polythermal section SnAs – SnP3. Taking into account the phase equilibrium scheme of the Sn – As – P ternary system and the obtained data on the confi guration of the region of existence of homogeneous solid solutions of phosphorus in the tin monoarsenide, a phase subsolidus demarcation scheme of the phase diagram of this system was carried out.

We present a method for laser lithography of cell-adhesive arrays on a fluoropolymer surface. The method is based on 172 nm excimer-lamp photomodification in ammonia atmosphere followed by microstructuring by laser ablation. The improved wettability of the polymer is caused by new chemical groups on the surface after the UV treatment that we proved by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses. The cell adhesion properties of micropatterned structures were tested by cultivation of mammalian cells. We show that single elongated cells can grow confined to lines with sharply defined boundaries of the cell-covered areas. In preliminary experiments, we also demonstrate that the described technique allows the production of single-cell arrays with variable cell shape. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012. [ABSTRACT FROM AUTHOR]

Bayesian analysis has been applied to polarized neutron reflectivity data. Reflectivity data from a magnetic TbCo thin‐film structure were studied using a combination of a Monte Carlo Markov‐chain algorithm, likelihood estimation and error modeling. By utilizing Bayesian analysis, it was possible to investigate the uniqueness of the solution beyond reconstructing the magnetic and structure parameters. The expedience of this approach has been demonstrated, as several probable reconstructions were found (the multimodality case) concerning the isotopic composition of the surface cover layer. Such multimodal reconstruction emphasizes the importance of rigorous data analysis instead of the direct data fitting approach, especially in the case of poor statistically conditioned data typical for neutron reflectivity experiments. This article presents details of the analysis and a discussion of multimodality. [ABSTRACT FROM AUTHOR]

A detailed theoretical review of phase retrieval algorithms, including the generalized Gerchberg–Saxton algorithm and some of its modifications, is presented. The possibility of applying phase retrieval algorithms to study the magnetic domain structure by dichroic coherent diffractive imaging is investigated on numerical examples. An optimal strategy for analyzing experimental data, stable to their nonidealities, is developed. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanotube (SWCNT)-based membranes (pellicles) and gas counterflows are used as a debris mitigation system in extreme ultraviolet (EUV) lithography. Densification with volatile liquids is a well-known approach to tune the performance of SWCNT membranes. However, densification can change the gas permeability through SWCNT membranes, violating the circulation of buffer gas counterflows. In the present work, we investigate the Ar permeability through SWCNT membranes before and after densification with isopropyl alcohol in the pressure drop test. The effective diffusivity of Ar through pristine and densified SWCNT membranes is, respectively, calculated to be Deffpristine = 330 × 109 m2 s−1 and Deffdensified = 4 × 109 m2 s−1. We developed a probabilistic model of gas penetration through SWCNT membranes. On the basis of the experimental data, the probabilities of Ar atoms penetrating through pristine and densified SWCNT membranes are estimated to be 8% and 0.1%, respectively. Structural changes in SWCNT membranes after densification with scanning electron microscopy and the Brunauer–Emmett–Teller technique are demonstrated. The bulk density of SWCNT membranes, measured using x-ray reflectometry, is found to be 0.38 and 0.89 g/cm3 before and after densification, respectively. The temporal dynamic of isopropyl alcohol evaporation from the volume of SWCNT membranes is analyzed using Fourier-transform infrared spectroscopy (FTIR). Results obtained using EUV and FTIR spectroscopy show that isopropyl alcohol is present in the volume of the SWCNT membrane even after the membrane has been left in vacuum (P < 0.01 Pa) for 22 h. [ABSTRACT FROM AUTHOR]

The market of Russian bonds denominated in foreign currencies was considered as the primary target for the initial package of the USA and EU economic sanctions in 2014. The analyses showed that, by the end of 2017, there was a significant reduction in the number of outstanding bond issues denominated in foreign currencies and a sharp increase in the bonds nominal volume evaluated in Russian rubles. The sanctions did not lead to a significant change in the structure of the market either from the standpoint of the number of bond issues denominated in foreign currencies or in terms of their nominal value. However, the number of foreign currencies in which bond issues were denominated was reduced from 11 to 6.

The molecular mechanisms of the interaction of anticancer antibiotic doxorubicin with lipid cell membrane models have been investigated using grazing incidence X-ray diffraction (XRD) and X-ray reflectivity (XRR). The model systems were monolayers of four types of phospholipids, related to the main components of animal cell membranes. New information on the processes of damage of phospholipid monolayer lattice caused by doxorubicin is obtained. It is established that the action of doxorubicin on anionic phospholipid monolayers is determined by the electrostatic interaction: positively charged doxorubicin molecules are incorporated between negatively charged phospholipid functional groups. In the case of neutral phospholipids the key role belongs to the hydrophobic interaction: doxorubicin molecules are coordinated with phospholipid hydrocarbon tails in disordered regions. [ABSTRACT FROM AUTHOR]

Recent research has demonstrated the high potential of grazing-emission X-ray fluorescence as a nanometrology tool for structures with complex 3D architecture. The technique now allows separate reconstruction of the spatial atomic distributions of different chemical elements both vertically and laterally, which opens up new and interesting applications in the nanofabrication industry. This study compares grazing-emission fluorescence with the well established grazing-incidence X-ray fluorescence method. The comparison uses a simple 1D thin-film structure. Reconstruction of the structure by both methods is performed and the statistical uncertainties of these reconstructions are compared by means of Monte Carlo Markov-chain simulations. For the forward model a semi-analytic approach is derived which allows simulation of the fluorescence intensity. This approach takes into account both grazing-incidence and grazing-emission cases. It also accounts for an even more complex physical phenomenon, the anomalous Kossel effect. Finally, using this semi-analytic approach, an experimental scheme combining grazing-incidence and grazingemission X-ray fluorescence is studied theoretically. [ABSTRACT FROM AUTHOR]

The morphology of supermultiperiod Al0.3Ga0.7As/GaAs superlattices grown by molecular-beam epitaxy has been determined using X-ray reflectometry (including the one on a synchrotron source) and photoluminescence. The layer thicknesses of a superlattice with 100 periods determined in laboratory and synchrotron studies correlate with an error of ~1%. Reflection peaks, which are not observed in measurements on a diffractometer and are likely related to the technological growth features of these structures, are revealed on a synchrotron beginning with high (>4–5) Bragg orders. It is analytically shown that these peaks correspond to modulation in the superlattice with a period that is three to five times larger and characterize the thickness dispersion over the structure depth of a few percent. [ABSTRACT FROM AUTHOR]

A theoretical formalism for quantitative description of X-ray diffraction from Langmuir monolayers under conditions of total external reflection has been developed. The proposed approach, based on the distorted-wave approximation, allows to consider physical mechanisms for plotting diffraction curves and maps (in the reciprocal space) for real monolayers and describe self-consistently specific features of Bragg peaks. The resulting algorithm can easily be implemented on a personal computer, which provides the opportunities to carry out numerical simulation of experimental two-dimensional diffraction intensity maps and determine reliably both the mean values of structural parameters of layers and their rms deviations. [ABSTRACT FROM AUTHOR]

A low-concentration nitrogen oxide recovery unit with a capacity of 50 m3/h equipped with γ-Al2O3 granules saturated with a water solution of carbamide and ammonium bicarbonate has been developed, produced, and tested. During the tests, the unit operated for approximately 176 h; it maintained capture efficiency at a level of 90 to 95% for 156 h. The unit captured 3.6 kg of nitrogen dioxide during its operation period. [ABSTRACT FROM AUTHOR]

The increasing structural complexity and downscaling of modern nanodevices require continuous development of structural characterization techniques that support R&D and manufacturing processes. This work explores the capability of laboratory characterization of periodic planar nanostructures using 3D X-ray standing waves as a promising method for reconstructing atomic profiles of planar nanostructures. The non-destructive nature of this metrology technique makes it highly versatile and particularly suitable for studying various types of samples. Moreover, it eliminates the need for additional sample preparation before use and can achieve sub-nanometre reconstruction resolution using widely available laboratory setups, as demonstrated on a diffractometer equipped with a microfocus X-ray tube with a copper anode., (© Ksenia Matveevskii et al. 2024.)

The results of a study of the structural and reflective characteristics of short-period multilayer X-ray mirrors based on Mo/B 4 C at wavelengths 1.54 Å, 9.89 Å and 17.59 Å are presented. The period of the samples varied in the range 8-35 Å. The average widths of the interfaces were ∼3.5 and 2.2 Å at one and the other boundaries, with a tendency for weak growth with any decrease in the period. The interlayer roughness was ∼1 Å. The research results indicate promising prospects for the use of multilayer Mo/B 4 C mirrors for synchrotron applications., (open access.)

The nanosecond speed of information writing and reading is recognized as one of the main advantages of next-generation non-volatile ferroelectric memory based on hafnium oxide thin films. However, the kinetics of polarization switching in this material have a complex nature, and despite the high speed of internal switching, the real speed can deteriorate significantly due to various external reasons. In this work, we reveal that the domain structure and the dielectric layer formed at the electrode interface contribute significantly to the polarization switching speed of 10 nm thick Hf 0.5 Zr 0.5 O 2 (HZO) film. The mechanism of speed degradation is related to the generation of charged defects in the film which accompany the formation of the interfacial dielectric layer during oxidization of the electrode. Such defects are pinning centers that prevent domain propagation upon polarization switching. To clarify this issue, we fabricate two types of similar W/HZO/TiN capacitor structures, differing only in the thickness of the electrode interlayer, and compare their ferroelectric (including local ferroelectric), dielectric, structural (including microstructural), chemical, and morphological properties, which are comprehensively investigated using several advanced techniques, in particular, hard X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, and electron beam induced current technique.

Lead halide perovskite (LHP) nanocrystals (NCs) have gathered much attention as light-emitting materials, particularly owing to their excellent color purity, band gap tunability, high photoluminescence quantum yield (PLQY), low cost, and scalable synthesis. To enhance the stability of LHP NCs, bulky strongly bound organic ligands are commonly employed, which counteract the extraction of charge carriers from the NCs and hinder their use as photoconductive materials and photocatalysts. Replacing these ligands with a thin coating is a complex challenge due to the highly dynamic ionic lattice, which is vulnerable to the commonly employed coating precursors and solvents. In this work, we demonstrate thin (<1 nm) metal oxide gel coatings through non-hydrolytic sol-gel reactions. The coated NCs are readily dispersible and highly stable in short-chain alcohols while remaining monodisperse and exhibiting high PLQY (70-90%). We show the successful coating of NCs in a wide range of sizes (5-14 nm) and halide compositions. Alumina-gel-coated NCs were chosen for an in-depth analysis, and the versatility of the approach is demonstrated by employing zirconia- and titania-based coatings. Compact films of the alumina-gel-coated NCs exhibit electronic and excitonic coupling between the NCs, leading to two orders of magnitude longer photoluminescence lifetimes (400-700 ns) compared to NCs in solution or their organically capped counterparts. This makes these NCs highly suited for applications where charge carrier delocalization or extraction is essential for performance., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

The long search for nontoxic alternatives to lead halide perovskites (LHPs) has shown that some compelling properties of LHPs, such as low effective masses of carriers, can only be attained in their closest Sn(II) and Ge(II) analogues, despite their tendency toward oxidation. Judicious choice of chemistry allowed formamidinium tin iodide (FASnI 3 ) to reach a power conversion efficiency of 14.81% in photovoltaic devices. This progress motivated us to develop a synthesis of colloidal FASnI 3 NCs with a concentration of Sn(IV) reduced to an insignificant level and to probe their intrinsic structural and optical properties. Intrinsic FASnI 3 NCs exhibit unusually low absorption coefficients of 4 × 10 3 cm -1 at the first excitonic transition, a 190 meV increase of the band gap as compared to the bulk material, and a lack of excitonic resonances. These features are attributed to a highly disordered lattice, distinct from the bulk FASnI 3 as supported by structural characterizations and first-principles calculations.

Extreme miniaturization of infrared spectrometers is critical for their integration into next-generation consumer electronics, wearables and ultrasmall satellites. In the infrared, there is a necessary compromise between high spectral bandwidth and high spectral resolution when miniaturizing dispersive elements, narrow band-pass filters and reconstructive spectrometers. Fourier-transform spectrometers are known for their large bandwidth and high spectral resolution in the infrared; however, they have not been fully miniaturized. Waveguide-based Fourier-transform spectrometers offer a low device footprint, but rely on an external imaging sensor such as bulky and expensive InGaAs cameras. Here we demonstrate a proof-of-concept miniaturized Fourier-transform waveguide spectrometer that incorporates a subwavelength and complementary-metal-oxide-semiconductor-compatible colloidal quantum dot photodetector as a light sensor. The resulting spectrometer exhibits a large spectral bandwidth and moderate spectral resolution of 50 cm -1 at a total active spectrometer volume below 100 μm × 100 μm × 100 μm. This ultracompact spectrometer design allows the integration of optical/analytical measurement instruments into consumer electronics and space devices., Competing Interests: Competing interestsM.J.G., I.S., and M.V.K are named as inventors on a patent application ‘Component for building a miniaturized spectrometer and method for using it’ by the Swiss Federal Laboratories for Materials Science and Technology—Empa (application no. EP22167959; status, pending). The other authors declare no competing interests., (© The Author(s) 2022.)