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The impact of crystallinity on the electret charge stability in binary blends of polypropylene (PP) homopolymers was been investigated with mechanical, rheological, calorimetric, and dielectric techniques. This showed that the incorporation of a low isotactic, high molecular weight PP into high isotactic PP (iPP) decreases the overall crystallinity according to the blend ratio, whereas the crystal melting temperature of the iPP phase is hardly affected as observed using differential scanning calorimetry (DSC). At the same time, the electret charge stability decreases considerably as revealed by thermally stimulated surface potential decay (TSSPD), despite a substantial fraction of the highly isotactic PP remaining crystalline. This suggests that, notwithstanding the unchanged iPP crystal melting temperature, the overall increase of the noncrystalline fraction reduces the charge stability by disrupting the polymer macrostructure and affecting the composition of the crystal-amorphous interphase layers. The increase in amorphous fraction was supported by a more pronounced glass transition in both dynamic mechanical analysis (DMA) and DSC. The blend rheology was analyzed by melt flow index (MFI) and parallel plate rheology. This gave further insights in the molecular weight distribution of the polymer samples and the flow behavior in shear rate regions commonly encountered within extrusion processes.

In this study, PrBa0.5Sr0.5Co1.5Fe0.5O6−δ(PBSCF) oxide with a layered double perovskite structure was successfully synthesized and characterized using the combination of X-ray diffraction (XRD) and energy-dispersive X-ray (EDX) methods. Oxygen content and electrical conductivity of PBSCF were measured at elevated temperatures and variable oxygen partial pressures. The corresponding experimental data were successfully analyzed using earlier proposed defect formation and transport models; the obtained results were additionally supported by magnetic experiments. The studied oxide was found to possess weak superstructural ordering at low δ values. Additionally, a noticeable chemical expansion anomaly was uncovered for PBSCF. Currently existing models of chemical deformation in nonstoichiometric oxides were shown to be inefficient for interpreting the data obtained, although a reasonable explanation was proposed on the basis of a more fundamental approach. Nevertheless, the peculiarity revealed was shown to be crucial for providing enhanced ionic mobility for oxygen anions in the PBSCF lattice, thus giving a reasonable explanation to the known superiority of PBSCF as a positrode material when compared to other layered cobaltites.

In distance-bounding authentication protocols the Prover has to prove not only that it is a legitimate participant, but also that it is in a legitimate zone (e.g., in close proximity to the Verifier). Conventional authentication protocols are not designed to deal with the location of protocol parties. Using such protocols in case of RFID systems makes them vulnerable to simple relay attacks, which is a significant threat. Protocols that combine cryptographic mechanisms with technical measurements (e.g., time-of-flight or GPS location of the Prover) are often used to protect against relay attacks. In this paper we analyse existing distance-bounding authentication protocols and propose a new DB-RFIDdistance-bounding protocol for RFID systems. DB-RFIDprotocol develops the ideas of the most prominent Swiss-Knifeprotocol, which protects against a greater number of possible attacks. We also provide an initial security analysis of the protocol and propose a version of the protocol based on Russian standardized cryptographic algorithms.

Doping of nano- and microparticles of oxides with rare earth elements (REEs) is used to fine-tune their structural, optical, and electrochemical properties. On the way to establish the structure–property relationship, we dope tantalum oxide (Ta2O5) particles with REEs to study their effect on the oxide structure and luminescence. Ta2O5is highly perspective in medicine, catalysis, and optics, but its crystal structure is insufficiently studied. Two synthesis approaches (sol–gel and solvothermal) were used to obtain powders with different textures. Experimental and theoretical studies of amorphous and crystallized tantalum oxide NPs by means of X-ray powder diffraction, Rietveld analysis, EXAFS/XANES spectroscopy, and density functional theory calculations were performed. All samples (doped and undoped) crystallized in orthorhombic phase with no admixtures. It was demonstrated that Ta2O5is a promising wide-spectrum luminescent material: by combining REEs, both Stokes and anti-Stokes luminescence in the visible region were obtained. By means of optical absorption spectroscopy, it was shown that the prepared samples could be classified as wide band gap semiconductors.

The dispersion of aerosols originating from one source, the ‘index’ passenger, within the cabin of the aircraft Do728 is studied experimentally using an aerosol-exhaling thermal manikin and in Reynolds-averaged Navier–Stokes simulations (RANS). The overall aim of the present study is the experimental determination of the aerosol spreading for the state-of-the-art mixing ventilation (MV) and to evaluate the potential of alternative ventilation concepts for controlling the aerosol spreading in RANS. For MV, the experiments showed that the ratio of inhaled to exhaled aerosol particles drops below 0.06% (volume ratio) for distances larger than two seat rows from the source. However, within a single row, the observed ratio is higher. Further, the dispersion is much weaker for a standing than for a seated index passenger. High air exchange rates and a well-guided flow prevent a dispersion of the aerosols in high concentrations over larger distances. Additionally, the positive effect of a mask and an increased air flow rate, and especially their combination are shown. In the complementary conducted RANS, the advantages of floor-based cabin displacement ventilation (CDV) which is alternative ventilation concept to MV, regarding spreading lengths and the dwell time of the aerosols in the cabin were determined. The obtained results also underline the importance of the flow field for the aerosol dispersion. Further, additional unsteady RANS (URANS) simulations of the short-term process of the initial aerosol cloud formation highlighted that the momentum decay of the breathing and the evaporation processes take place within a few seconds only.

A preliminary criticality analysis for novel pyrochemical apparatuses for the reprocessing of mixed uranium-plutonium nitride spent nuclear fuel from the BREST-OD-300 reactor was performed. High-temperature processing apparatuses, “metallization” electrolyzer, refinery remelting apparatus, refining electrolyzer, and “soft” chlorination apparatus are considered in this work. Computational models of apparatuses for two neutron radiation transport codes (MCU-FR and MCNP) were developed and calculations for criticality were completed using the Monte Carlo method.

The microstructural and mechanical properties of pressuless sintered SiC-based composite materials with Al or Cu addition (0–10 wt.%) were studied. The introduction of 1–2 wt.% of metals to the SiC results in appreciable porosity decreases from 31 to 19 ± 1%. Moreover, metallic aids considerably affects the phase composition of the materials. Cu suppresses the formation of mullite. In contrast, Al increases the content of the moissanite phase in the final material because of a thick oxide film on the surface of silicon carbide. However, metal content does not steadily increases due to the melt removes from the open pores during the sintering process. The hardness of the composite material mainly depends on the moissanite phase content, which could be enhanced by metal additives. Developed composite materials have up to 50 and 3 times greater resistance to abrasive and cavitation wear correspondingly than the original porous SiC.

In addition to general challenges in drug discovery such as the identification of lead compounds in time- and cost-effective ways, specific challenges also exist. Particularly, it is necessary to develop pharmacological inhibitors that effectively discriminate between closely related molecular targets. DYRK1B kinase is considered a valuable target for cancer-specific mono- or combination chemotherapy; however, the inhibition of its closely related DYRK1A kinase is not beneficial. Existing inhibitors target both kinases with essentially the same efficiency, and the unavailability of the DYRK1B crystal structure makes the discovery of DYRK1B-specific inhibitors even more challenging. Here, we propose a novel multi-stage compound discovery pipeline aimed at in silicoidentification of both potent and selective small molecules from a large set of initial candidates. The method uses structure-based docking and ligand-based quantitative structure–activity relationship modeling. This approach allowed us to identify lead and runner-up small-molecule compounds targeting DYRK1B with high efficiency and specificity.

Inorganic–organic hybrid luminescent materials have received great attention for their potential applications in a wide range of clean/renewable energy-related areas, including photovoltaics and solid-state lighting. Herein, we present a unique and general “Mn + Cu” approach by blending two earth-abundant luminogenic metals, manganese and copper, within a single ionic structure to construct a remarkable family of low-cost and multifunctional hybrid materials featuring dual emission, as well as triboluminescence and second-harmonic generation response. The novel hybrid materials are made of diphosphine dioxide-chelated [Mn(O∧O)3]2+cations and various anionic [CuxIy](y−x)–clusters, ensuring manifestation of dual phosphorescence streamed from octahedral Mn2+ions (605–648 nm) and iodocuprate anions (480–728 nm). Noteworthily, the relative ratio of the emission bands, and hence a resulting emission chromaticity, can be tuned in a wide range through modification of cluster [CuxIy](y−x)–modules. The structural diversity, enhanced robustness, and up to 100% luminescence quantum yield make the designed materials promising phosphors for lighting and sensing applications.

Abstract—: The antifungal activity of fine submicron-size particles of WO3and RbTe1.5W0.5O6against the spores and vegetative mycelium of Aspergillus nigerand Penicillium chrysogenumfungi is studied. It is found that the studied compounds WO3and RbTe1.5W0.5O6caused a decrease in the survival rate of microorganisms in the dark. Antifungal activity increased against both the spores and vegetative mycelium of fungi under light exposure with a power of 30 and 50 W with a radiation-flux density of 325.5 and 524 W/m2, respectively, which indicates their photocatalytic activity. It is noted that the antifungal activity of RbTe1.5W0.5O6both under light and dark conditions on the spores and vegetative mycelium of fungi is higher compared to WO3. The antifungal effect of the compounds under study increased with an increase in the duration of exposure and the intensity of illumination.

Discovery of interaction sites between RNA-binding proteins (RBPs) and their RNA targets plays a critical role in enabling our understanding of how these RBPs control RNA processing and regulation. Cross-linking and immunoprecipitation (CLIP) provides a generalizable, transcriptome-wide method by which RBP/RNA complexes are purified and sequenced to identify sites of intermolecular contact. By simplifying technical challenges in prior CLIP methods and incorporating the generation of and quantitative comparison against size-matched input controls, the single-end enhanced CLIP (seCLIP) protocol allows for the profiling of these interactions with high resolution, efficiency and scalability. Here, we present a step-by-step guide to the seCLIP method, detailing critical steps and offering insights regarding troubleshooting and expected results while carrying out the ~4-d protocol. Furthermore, we describe a comprehensive bioinformatics pipeline that offers users the tools necessary to process two replicate datasets and identify reproducible and significant peaks for an RBP of interest in ~2 d.

The antimicrobial activity of fine particles of submicron size WO3and RbTe1.5W0.5O6in relation to the bacteria Escherichia coliand Staphylococcus aureusis studied. It is found that all the studied compounds cause a decrease in the survival of bacteria both in the dark and in the light. It is shown that a decrease in the size of RbTe1.5W0.5O6particles enhances their antimicrobial effect. The action of light (source power 30 and 50 W) enhances the antimicrobial activity of the compounds under study, especially for RbTe1.5W0.5O6with a smaller particle size, which indicates their photocatalytic activity. With an increase in the duration of exposure, the antimicrobial effect of the studied compounds increases. The ambiguity of the effect of light sources of different power on the bacteria is noted, which may be due to their physiological and biochemical characteristics.

This article discusses the contents of a collection formerly owned by Axel Oxenstierna (1583–1654) and now held by the National Library of Russia (St. Petersburg). This archive of the Chancellor of Sweden is particularly rich in diplomatic material as Oxenstierna led that country’s foreign policy during the final phase of the Thirty Years War (1618–1648). The context of this collection, the historical value of these documents, and a list of all the Chancellor’s correspondents, as well as of his own autographs are documented in this article.

In this Letter, optical-to-terahertz (THz) conversion of 800 nm femtosecond laser pulses in large-area bias-free InGaAs emitters based on photo-Dember (PD) and lateral photo-Dember (LPD) effects is experimentally investigated. We use metamorphic buffers to grow sub-micrometer thick In_xGa_1−xAs layers with indium mole fractions x=0.37, 0.53, and 0.70 on a GaAs substrate. A strong enhancement of THz output energy with an increase of indium content is observed. On the surface of the sample providing the strongest emission (x=0.7), we have fabricated a 1.5cm^2 area of asymmetrically shaped metallic grating for LPD emission. This LPD emitter allows achieving high conversion efficiency of 0.24⋅10^−3 and a broad generation bandwidth of up to 6 THz. We also demonstrate that there is no significant difference in the conversion efficiency when operating at 1 and 200 kHz repetition rates. Our results show that large-area LPD emitters give a convenient, competitive way to generate intense high-repetition-rate THz pulses.

Abstract: The dependence of soft magnetic properties of the Fe73.5Si13.5Nb3Cu1B9alloy on the 2-hour air annealing temperature Tanat temperatures from 520 to 620°C is studied. It is shown that the magnetic hysteresis loop is significantly broadens and becomes more inclined, and the Curie temperature of the amorphous matrix surrounding α-FeSi nanocrystals decreases with increasing Tan. The atomic structure and phase composition of alloy samples are studied by transmission X-ray diffraction. After annealing at temperatures to 580°C, nanocrystals contain mostly D03phase (Fe3Si stoichiometry) and are ~7 nm in average size. Their relative fraction in the alloy increases with temperature due to additional iron diffusion from the matrix to nanocrystals. After annealings at Tan> 600°C, the average nanocrystal size increases, and iron boride crystal reflections appear in X-ray diffraction patterns. Degradation of soft magnetic properties of nanocrystalline Fe73.5Si13.5Nb3Cu1B9alloy with annealing temperature from 520 to 580°C is explained by a decrease in the silicon concentration in FeSi nanocrystals, which results in an increase in the magnetocrystalline anisotropy.

We consider the issues of measuring the deformability of red blood cells by the method of laser diffractometry in shear flow (ektacytometry). The measurement procedure is optimised taking into account the finite resolution of the video recording system of the laser ektacytometer. An algorithm is proposed that allows one to determine with high accuracy the diffraction pattern parameters necessary for measuring the characteristics of the erythrocyte deformability distribution.

The paper is concerned with continuous linear operators on the space of entire functions. The properties of such operators that are related to the definition of convolution-type operators in spaces of analytic functions are investigated. Corollaries refining both the approximation theorem for the kernel of a symmetric convolution operator and the dual definition of a differential operator in a complex domain are stated.

The article gives the description of experimental studies on the assessment of changes in the state of gear teeth of a mechanical transmission during tests on a stand with a closed power flow. Data on the gears made of cast iron materials are presented. The strength characteristics of gear wheel materials and their chemical composition are given. Operational life testing of gear sets with various geometries of gearing and made of gray cast was carried out. According to the conducted studies, it is found that by the optimization of the gearing parameters it is possible to increase the gear life by one and a half to two times without switching to more wear-resistant and durable materials. It is experimentally proved that the influence of geometrical parameters of gearing with combined displacement on the durability of gears is comparable with the replacement of material. When replacing the material of gears made of gray cast iron with alloy grades of cast iron, preference should be given to high-alloy wear-resistant cast iron with a surface hardness above average, and the effect of their use can be comparable to the effect of optimizing the gearing parameters.

The convergence of difference schemes on uniform grids for an initial-boundary value problem for a singularly perturbed parabolic convection-diffusion equation is studied; the highest x-derivative in the equation is multiplied by a perturbation parameter ε taking arbitrary values in the interval (0,1]{(0,1]}. For small ε, the problem involves a boundary layer of width 𝒪⁢(ε){\mathcal{O}(\varepsilon)}, where the solution changes by a finite value, while its derivative grows unboundedly as ε tends to zero. We construct a standard difference scheme on uniform meshes based on the classical monotone grid approximation (upwind approximation of the first-order derivatives). Using a priori estimates, we show that such a scheme converges as {ε⁢N},N0→∞{\{\varepsilon N\},N_{0}\to\infty}in the maximum norm with first-order accuracy in {ε⁢N}{\{\varepsilon N\}}and N0{N_{0}}; as N,N0→∞{N,N_{0}\to\infty}, the convergence is conditional with respect toN, where N+1{N+1}and N0+1{N_{0}+1}are the numbers of mesh points in xand t, respectively. We develop an improveddifference scheme on uniform meshes using the grid approximation of the first x-derivative in the convective term by the centraldifference operator under the conditionh≤m⁢ε{h\leq m\varepsilon}, which ensures the monotonicity of the scheme; here mis some rather small positive constant. It is proved that this scheme converges in the maximum norm at a rateof 𝒪⁢(ε-2⁢N-2+N0-1){\mathcal{O}(\varepsilon^{-2}N^{-2}+N^{-1}_{0})}. We compare the convergence rate of the developed scheme with the known Samarskii scheme for a regularproblem. It is found that the improved scheme (for ε=1{\varepsilon=1}), as well as the Samarskii scheme, converges in the maximum normwith second-order accuracy inxand first-order accuracy int.

Abstract: The concentration dependence of magnetic properties of iron alloys with 3–25% of gallium is studied. It was shown that the saturation induction monotonically decreases with increasing gallium content, while the coercivity exhibits a step increase with a step from 85 to 135 A/m between 12 and 15 at % Ga. The effect of magnetic field annealing (MFA) on the behavior of the residual induction and coercive force in alloy samples containing from 3 to 18 at % Ga is studied. As a result of MFA, magnetic anisotropy is induced in the alloy: magnetic hysteresis loops become narrower, the residual induction increases, and the coercivity decreases. The MFA efficiency reaches a maximum at a Ga content of 15–18 at %. The features of the structure state of iron–gallium alloys and their role in the formation of magnetic properties during annealing in a dc magnetic field are discussed.

The iso-intensity line curvature algorithm in laser ektacytometry of red blood cells is investigated by numerical simulation. The algorithm is designed to measure the average deformability, as well as the width and asymmetry of the red blood cell deformability distribution in a blood sample under study. The accuracy and scope of the algorithm are determined. Using a bimodal ensemble as an example, the possibility of determining the fraction of weakly deformable red blood cells in a blood sample by laser ektacytometry is demonstrated.

Genetic screens using pooled CRISPR-based approaches are scalable and inexpensive, but restricted to standard readouts, including survival, proliferation and sortable markers. However, many biologically relevant cell states involve cellular and subcellular changes that are only accessible by microscopic visualization, and are currently impossible to screen with pooled methods. Here we combine pooled CRISPR–Cas9 screening with microraft array technology and high-content imaging to screen image-based phenotypes (CRaft-ID; CRISPR-based microRaft followed by guide RNA identification). By isolating microrafts that contain genetic clones harboring individual guide RNAs (gRNA), we identify RNA-binding proteins (RBPs) that influence the formation of stress granules, the punctate protein–RNA assemblies that form during stress. To automate hit identification, we developed a machine-learning model trained on nuclear morphology to remove unhealthy cells or imaging artifacts. In doing so, we identified and validated previously uncharacterized RBPs that modulate stress granule abundance, highlighting the applicability of our approach to facilitate image-based pooled CRISPR screens.

Over the last five years, inorganic lead halide perovskite nanowires have emerged as prospective candidates to supersede standard semiconductor analogs in advanced photonic designs and optoelectronic devices. In particular, CsPbX3(X = Cl, Br, I) perovskite materials have great advantages over conventional semiconductors such as defect tolerance, highly efficient luminescence, and the ability to form regularly shaped nano- and microcavities from solution via fast crystallization. However, on the way of electrically pumped lasing, the perovskite nanowires grown on transparent conductive substrates usually suffer from strong undesirable light leakage increasing their threshold of lasing. Here, we report on the integration of CsPbBr3nanowires with nanostructured indium tin oxide substrates possessing near-unity effective refractive index and high conductivity by using a simple wet chemical approach. Surface passivation of the substrates is found out to govern the regularity of the perovskite resonators’ shape. The nanowires show room-temperature lasing with ultrahigh quality factors (up to 7860) which are up to four times higher than that of similar structures on a flat indium tin oxide layer, resulting in more than twofold reduction of the lasing threshold for the nanostructured substrate. Numerical modeling of eigenmodes of the nanowires confirms the key role of low-refractive-index substrate for improved light confinement in the Fabry–Pérot cavity which results in superior laser performance.

The interaction between UN and CdCl2in the LiCl-KCl molten eutectic was studied at 773 K.