We have studied the formation, polymorphism, and electrical conductivity of Bi2O3-based compounds with the general formula (Bi2O3)x(Nd2O3)y(MoO3)z (x + y + z = 1) in the ternary system ...Bi2O3–Nd2O3–MoO3. It has been shown that the system contains Bi2O3-based solid solutions with cubic, tetragonal, monoclinic, and rhombohedral structures, depending on composition. Bi2O3-based compounds with the cubic fluorite structure have been identified in two broad composition regions: 0.56 ≤ x ≤ 0.9, 0.03 ≤ y ≤ 0.22, 0.03 ≤ z ≤ 0.23 and 0.36 ≤ x ≤ 0.6, 0.25 ≤ y ≤ 0.47, 0 ≤ z ≤ 0.21. In addition, a large region of tetragonal compounds has been detected, with 0.37 ≤ x ≤ 0.56, 0.19 ≤ y ≤ 0.38, and 0.23 ≤ z ≤ 0.33. The conductivity of the samples studied increases with Bi2O3 concentration: from 0.01 ((Bi2O3)0.36(Nd2O3)0.45(MoO3)0.19 sample) to 0.7 S/cm ((Bi2O3)0.9(Nd2O3)0.07(MoO3)0.03 sample) at 800 °C. The cubic and tetragonal symmetries of the samples persist after rapid heating and cooling, but prolonged annealing in a limited temperature range can lower the symmetry of some samples. Heating the samples to above their instability range restores their original structure and properties. In addition, we have identified (Bi2O3)x(Nd2O3)y(MoO3)z compounds that remain stable, without symmetry changes, at any temperature, even at long annealing times.
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•Wide stability fields of Bi2O3-based phases exist in Bi2O3–Nd2O3–MoO3 system.•Cubic, tetragonal, monoclinic, and rhombohedral compounds were found.•Some compounds may decrease their symmetry in a limited temperature range.•Some compounds remain stable at any temperatures and annealing time.•The conductivity rises with increase of Bi2O3 concentration.
The secondary beam diagnostics at the ACCULINNA-2 fragment separator is implemented event-by-event by the beam particle detector, allowing one to identify the projectile ion with the dE-ToF method ...and determine the ion’s velocity vector and localization on the target. The detector comprises two ToF stations and a pair of MWPCs. Two identical ToF stations located on the straight section of the ACCULINNA-2 fragment separator form a base of 12.35 m. In each station, light from a thin organic scintillator is detected with four compact PMTs directed symmetrically inside a closed volume. MWPCs are stationary shells designed to work in vacuum at atmospheric pressure of gas CF
4
. Each chamber provides
XY
coordinates with a pitch of 0.125 cm. This work studies the purpose and scope of application of the beam particles detector and its characteristics, layout, operation logic, as well as techniques of setting and calibration.
A fundamental limit to existing optical techniques for measurement and manipulation of spin degrees of freedom is set by diffraction, which does not allow spins separated by less than about a quarter ...of a micrometre to be resolved using conventional far-field optics. Here, we report an efficient far-field optical technique that overcomes the limiting role of diffraction, allowing individual electronic spins to be detected, imaged and manipulated coherently with nanoscale resolution. The technique involves selective flipping of the orientation of individual spins, associated with nitrogen-vacancy centres in room-temperature diamond, using a focused beam of light with intensity vanishing at a controllable location, which enables simultaneous single-spin imaging and magnetometry at the nanoscale with considerably less power than conventional techniques. Furthermore, by inhibiting spin transitions away from the laser intensity null, selective coherent rotation of individual spins is realized. This technique can be extended to subnanometre dimensions, thus enabling applications in diverse areas ranging from quantum information science to bioimaging. PUBLICATION ABSTRACT
The effect of metal nitrates on the activation of anthracite combustion process has been studied. Fe(NO
3
)
2
· 9H
2
O and Cu(NO
3
)
2
· 3H
2
O were used as nitrates in an amount of 5 wt% applied ...to anthracite powder (fraction less than 0.1 mm) by incipient wetness impregnation. Using scanning electron microscopy and EDX mapping, it was found that using this method of applying the additive makes it possible to achieve high dispersion and uniform distribution in the fuel composition. The characteristics of oxidation, ignition, and combustion were studied using thermal analysis methods and high-speed video recording in the combustion chamber at a temperature of 800°C. It was found that the use of metal nitrates contributes to an increase in the reactivity of anthracite as evidenced by a decrease in the temperature of the intensive oxidation beginning (ΔT
i
) by 23-84°C and the ignition delay time (Δt
i
) by 0.9-2.2 seconds. The greatest effect of changing the reactivity of anthracite was recorded in the case of using copper nitrate additive. The use of nitrates also contributed to the decrease in the resulting fuel underburning (from 3.5 to 0.4 wt%) and gas-phase CO compounds (by 31-53%). At the early stages, combustion process of modified samples was accompanied by periodic formation of micro-explosions, which led to the activation and development of the particle surface.
Recent technical advances in genomic technology have led to the explosive growth of transcriptome-wide studies at the level of single cells. The review describes the first steps of the single cell ...proteomics that has originated soon after development of transcriptomics methods. The first studies on the shotgun proteomics of single cells that used liquid chromatography/mass spectrometry have been already published. In these works, the cells were separated by the methods used in transcriptomics studies (e.g., cell sorting) and analyzed by modified mass spectrometry with tandem mass tags. The new proteogenomics approach involving integration of single cell transcriptomics and proteomics data will provide better understanding of the mechanisms of cell interactions in normal development and disease.
Over the last decade, magnetic iron oxide nanoparticles (IONPs) have drawn much attention for their potential biomedical applications. However, serious in vitro and in vivo safety concerns continue ...to exist. In this study, the effects of uncoated, FemOn-SiO2 composite flake-like, and SiO2-FemOn core-shell IONPs on cell viability, function, and morphology were tested 48 h postincubation in human umbilical vein endothelial cell culture. Cell viability and apoptosis/necrosis rate were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and annexin V-phycoerythrin kit, respectively. Cell morphology was evaluated using bright-field microscopy and forward and lateral light scattering profiles obtained with flow cytometry analysis. All tested IONP types were used at three different doses, that is, 0.7, 7.0, and 70.0 µg. Dose-dependent changes in cell morphology, viability, and apoptosis rate were shown. At higher doses, all types of IONPs caused formation of binucleated cells suggesting impaired cytokinesis. FemOn-SiO2 composite flake-like and SiO2-FemOn core-shell IONPs were characterized by similar profile of cytotoxicity, whereas bare IONPs were shown to be less toxic. The presence of either silica core or silica nanoflakes in composite IONPs can promote cytotoxic effects.
The effect of optical illumination in the visible band on the resistive switching in ITO/ZrO
2
(Y)/
n
-Si metal—oxide—semiconductor (MOS) structures (including those with Au nanoparticles embedded in ...the ZrO
2
(Y) layer) is studied. It is found that the dependence of the logical gap between the resistance states on the photoexcitation intensity had a threshold nature. The logical gap decreases with further increasing photoexcitation intensity above the threshold. This effect is ascribed to the heating of active layers of the MOS structure due to interband optical absorption in the Si substrate. The suppression of resistive switching by photoexcitation at a wavelength of 650 nm (corresponding to plasmon resonance in Au nanoparticles) due to plasmon optical absorption in nanoparticles is observed.
Fractal and pseudo-fractal microstructures have proved promising in increasing the range of detectable frequencies for devices used in the realm of electromagnetism. Due to mechanical-electrical ...duality it is conjectured they may provide flexible solutions capable of closing/widening bandgaps and increasing tailorability in phononic lattices. Pseudo-fractal hyper-lattices have been considered in this work and different aspects of dispersion surface morphology and frequency band structure are studied. It has been observed that higher frequencies that can be excited in the simple square lattice are almost the same as those in the pseudo-fractal structures, however; through introduction of higher levels the pseudo-fractal hyper-lattice presents new features not observable in the ordinary lattice. By increasing the order of pseudo-fractal structure the number of degrees-of-freedom increases and dispersion surfaces morphologies change thus frequency gaps are eliminated. This phenomenon can be of advantage for acoustic/phononic visibility/detectability e.g. in designing sensors. In the classical analogy to quantum level repulsion surfaces flatten which sufficiently decreases the sound group velocity in the pseudo-fractal structure, and can be used for numerous practical applications.
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•Pseudo-fractal hyper-lattices are considered with dispersion surface morphology and frequency band structure being studied.•Numerous dispersion surfaces form and eliminate bandgaps, a potentially useful feature for acoustic detectability.•As a classical analogy to quantum level-repulsion, sound group velocity decreases, which is useful in many applications.•The “rotating” and “displacing” modes correspond to separate wide frequency areas.•A wide bandgap for displacing modes works as a pass-band for rotating modes and vice versa.
The object of investigation is one-type neighbouring blocks of flats located in Volgograd region (Russia, N 48°). Thermophysical field testing using eco-friendly nondestructive test methods was ...carried out to estimate whether the level of heat protection in buildings meets requirements of the Russian construction norms SP 50.13330.2012. According to the results of thermophysical field tests of residential buildings made of autoclaved aerated concrete blocks, the following was found out. Design of double-layer exterior walls in the form of AAC blocks with front brick masonry bears thermotechnical risks due to an increase in non-uniform heat protection of buildings’ covers caused by a significant impact on heat protection of buildings’ edge zones. The designed level of heat insulation does not conform to the basic level of heat protection for the majority of regions in the Russian Federation. Two-layer exterior walls without supplementary insulation practically do not have heat protection and energy saving reserves. The reduction of the actual insulation in envelopes, compared to the designed one, can be explained by both unapproved deviations from the design project made by a subcontractor during construction and low-quality construction and assembly work. It is strongly suggested to improve the structural solution of edge zones in envelopes to reduce thermotechnical risks when designing buildings. Supplementary insulation along the surfaces of the walls can be considered as another activity to increase heat protection.
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