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Phase transformations in the alloy based on the orthorhombic titanium aluminide (Ti-24,3Al-24,8Nb-1,4V-1,0Zr-0,6Mo-0,3Si – at. %) were studied by differential thermal analysis. The alloy was quenched from the different phase regions (β+O, β+O+α2+(Vω), β+α2, β) and was subjected to continuous heating up to . It was found that the heating temperature of the O-alloy, which determines its phase state during quenching, affects the temperature ranges, intensity, and stages of the phase transformations during subsequent heating.

Complementary metal–oxide–semiconductor (CMOS) logic circuits at their ultimate scaling limits place extreme demands on the properties of all materials involved. The requirements for semiconductors are well explored and could possibly be satisfied by a number of layered two-dimensional (2D) materials, such as transition metal dichalcogenides or black phosphorus. The requirements for gate insulators are arguably even more challenging. At present, hexagonal boron nitride (hBN) is the most common 2D insulator and is widely considered to be the most promising gate insulator in 2D material-based transistors. Here we assess the material parameters and performance limits of hBN. We compare experimental and theoretical tunnel currents through ultrathin layers (equivalent oxide thickness of less than 1 nm) of hBN and other 2D gate insulators, including the ideal case of defect-free hBN. Though its properties make hBN a candidate for many applications in 2D nanoelectronics, excessive leakage currents lead us to conclude that hBN is unlikely to be suitable for use as a gate insulator in ultrascaled CMOS devices. This Perspective assesses the performance limits of hexagonal boron nitride when used as a gate insulator in complementary metal–oxide–semiconductor (CMOS) devices based on two-dimensional materials, concluding that due to excessive leakage currents, the material is unlikely to be suitable for use in ultrascaled CMOS devices.

A comprehensive analysis of extensive primary (morphological, geological, geophysical, and geochemical—including deep-sea drilling) data provides deep insight into the morphostructure, geology, and evolution of the West Australian Ridge (WAR) (or Broken Ridge), which unambiguously testify to its continental origin. The northeastern slope was distinguished additionally to two previously known main morphostructural elements of the ridge: the northern and southern slopes. It is inclined towards the Naturaliste abyssal plain and structurally forms its northwestern framing. It has been established that the morphology of the slopes is caused by the peculiarities of the tectonic development of the adjacent basins. It is determined that the sedimentary cover of the central part of the northern slope contains a lower (basal) seismoacoustic complex, which has not been exposed by deep-sea drilling and formed no later than the Early Cretaceous. The final subsidence of individual fragments of the ridge and the formation of its present-day morphostructure, as well as the structural-tectonic rearrangement of the adjacent areas, occurred at the youngest phase of tectonic activation in the Late Miocene–Pliocene.

—Scanning electron microscopy, electron microprobe and X-ray diffraction analyses, and durometry are used to study changes in the structure, phase composition, and hardness of a quenched titanium Ti‒10V–2Fe–3Al alloy in the course of aging at 500°С for 2–32 h. A complex analysis of changes in the lattice parameters of the primary and secondary α phases formed in the alloy during aging has been performed for the first time using full-profile X-ray diffraction analysis. Aging-induced changes in the hardness of the alloy are shown to be determined both by the sizes of formed secondary α-phase particles and changes in the alloying of the matrix β solid solution.

The methods of optical microscopy, x-ray phase analysis and microindentation are used to study the effect of vacuum annealing at 750, 800 and 850°C on the structure, phase composition and microhardness characteristics over cross section of welded joints of unlike alloys OT4 – VT6, VT20 – VT6 and VT23 – VT6. Recommendations are developed on the temperature of vacuum annealing of the welded compositions studied, which provide gradual variation of the hardness parameters in welded joints upon transition from the matrix metal of one alloy to the other.

Titanium alloy VTI-4 based on orthorhombic titanium aluminide Ti2AlNb is studied in the initial condition and after charging with hydrogen to different concentrations. The kinetics and the rate of hydrogen release from the hydrogen-charged alloys during a 30-min hold at 900°C in a flow of a high-purity inert gas (argon) is analyzed. The curves obtained by differential scanning calorimetry and thermal gravimetric analysis are plotted under continuous heating to 1200°C in the inert argon atmosphere at a rate of 20 K/min. The microstructure of the alloy is studied.

The purpose of this work is to study the structure and mechanical properties of an aluminum – magnesium system alloy after various types of heat treatment (quenching and ageing). The microstructure of an alloy has been studied by means of Zeiss OBSERVER.D1m microscope combined with a camera and image display on a monitor screen. Micro X-ray spectral analysis was performed by means of Carl Zeiss EVO 50 scanning electron microscope. The micro-hardness of the samples has been measured on prepared metallographic sections by means of DM8 micro-hardness meter. In the course of the process it has been found that quenching the Al-12,78% Mg alloy from temperatures of 430–440 ° C does not lead to the formation of a single-phase solid solution. Ageing at 100 ° C enables the formation of secondary phases. It was noted that with an increase in the quenching temperature, the micro-hardness increases slightly. An increase in the exposure time doesn’t influence greatly the micro-hardness of the alloy, while the structure remains practically unchanged.

The structure and phase composition of biocompatible titanium alloys of composition (wt %) Ti–10Zr–1.2Nb–1.5Al, Ti–6Al–4V (ELI), Ti–15Mo, and Ti–36.1Nb–3.8Zr–2.4Ta–1.9Sn have been studied in a hot-deformed state using scanning electron microscopy and X-ray diffraction analysis. The analysis of mechanical tensile properties has been performed depending on the structure and the aluminum strength equivalent of the alloys. The elasticity moduli of the alloys have been determined using tensile tests, dynamic mechanical analysis, and microindentation; the comparability of values within the error of 3–7% has been established. The nonmonotonic character of the change of the elasticity modulus upon heating to 550°C is explained in terms of the occurrence of processes of stress relaxation and recovery in the Ti–10Zr–1.2Nb–1.5Al, and Ti–6Al–4V ELI alloys and based on the precipitation of the high-modulus ω phase in the Ti–15Mo alloy. For the Ti–36.1Nb–3.8Zr–2.4Ta–1.9Sn alloy, the realization of the elinvar effect has been demonstrated. A correlation of the rate of change in the elasticity modulus with the heating temperature and the ratio of α and β phases in the structure of the alloys has been established.

Решается функциональное уравнение $$ f(x_1+z)\dotsb f(x_2+z)f(x_1+\dotsb+x_{s-1}-z) =\phi_1(x)\psi_1(z)+\dotsb+\phi_m(x)\psi_m(z), $$ где $x=(x_1,…,x_{s-1})$, относительно неизвестных $f,\psi_j\colon\mathbb C\to\mathbb C$, $\phi_j\colon\mathbb C^{s-1}\to\mathbb C$ при $s\ge 3$, $m\le 4s-5$. Библиография: 19 названий.

The following functional equation is solved: $$f\left( {{x_1} + z} \right) \cdots f\left( {{x_2} + z} \right)f\left( {{x_1} + \cdots + {x_{s - 1}} - z} \right) = {\phi _1}\left( x \right){\psi _1}\left( z \right) + \cdots + {\phi _m}\left( x \right){\psi _m}\left( z \right),$$ where x =(x1,…,xs−1), for the unknowns $$f,{\psi _j}:\mathbb{C} \to \mathbb{C}$$ and $${\phi _j}:{\mathbb{C}^{s - 1}} \to \mathbb{C}$$ for s ≥ 3 and m ≤ 4s − 5.

For the first time, a detonation afterburner (DA) for continuous detonation combustion of TS-1 aviation kerosene was developed, manufactured, and tested. Test fires of the DA in combination with a TJ100S-125 small-sized single-circuit turbojet engine were carried out on a ground test bench. In the test fires, stable modes of continuous detonation combustion of aviation kerosene were registered: a near-limit mode of longitudinally pulsating detonation (LPD) and a spin detonation (SD) mode with one detonation wave. Compared to a conventional afterburner, at the same in-chamber pressure, the specific fuel consumption in the DA was 30% lower and the specific thrust and thrust boosting coefficient were 30% higher. It is shown that, when operating in the LPD mode, the average heat flux to the DA walls is about 0.5 MW/m2 and, in the SD mode, 0.86 MW/m2. These values indicate the high potentiality of the DA when used in advanced jet engines.

One of the main problems with the use of metal implants is mechanical resorption, due to a significant difference in Young's moduli of bone tissue and metal material. This paper provides an overview of the main approaches for developing and optimizing the compositions of low-modulus alloys for medical implants. The choice of the base metal of such alloys – titanium, combining a low Young's modulus with complete biological inertness, -- is substantiated. Based on the analysis and systematization of the available literature data, the issues of choosing the optimal alloying to achieve a low Young's modulus, while maintaining biological compatibility, are considered. The main attention is paid to the Ti-Nb-Zr- (Ta, Sn) system as providing the maximum potential for reducing the Young's modulus. In addition, the importance of obtaining a certain structural and textural state in the product to further reduce the Young's modulus is noted.

Пусть $\Gamma$ - $s$-мерная решетка из $\mathbb R^s$. Выпуклые оболочки ненулевых узлов из $\Gamma$, содержащихся в каждом ортанте, называются полиэдрами Клейна решетки $\Gamma$. Эта конструкция была введена Ф. Клейном (1895 г.) в связи с обобщением классического алгоритма непрерывных дробей на многомерный случай. В. И. Арнольд сформулировал ряд задач о статистических и геометрических свойствах полиэдров Клейна. В двумерном случае соответствующие результаты вытекают из теории непрерывных дробей. В работе выводится асимптотическая формула для среднего значения $f$-вектора (количество граней, ребер и вершин) трехмерных полиэдров Клейна. Усреднение проводится по полиэдрам Клейна трехмерных целочисленных решеток с определителем из отрезка $[1,R]$, где $R$ - растущий параметр. Библиография: 27 названий.

The comprehensive analysis of geological, geophysical, and geochemical data makes it possible to obtain the most complete picture of the geological structure of the central part of the Ninety East Ridge (NER), the Osborn Plateau, and the adjacent part of the Central Basin. This region has been established to be a complex tectonic structure. In respect of the revealed structural features of the major near-NS faults of Indrani, Indira, and Lanka, they are not transform faults. Based on the generalization of all available data on the northern and southern parts of the NER, supplemented by the studies of the NER’s central part, it is found out that the NER was constructed on the continental crust of an ancient continent, likely Lemuria. According to a new formation model, the NER is a relict fragment of this continent, preserved in the form of a block or an escarp, as an extended horst structure. This paper involves the primary data obtained by different Russian scientific and production organizations in the course of expeditions in the Central Basin during the 1980–1990s, as well as other data, including those obtained from foreign sources.

—Changes in the structure, phase composition, microhardness, and modulus of elasticity upon thermohydrogen treatment of the VTI4 alloy based on the orthorhombic titanium aluminide Ti2AlNb alloyed with hydrogen to 12.5 at % have been studied using electron microscopy, X-ray diffraction analysis, and microindentation. It has been shown that the alloying of this alloy with hydrogen leads to a decrease in peak stresses and to an increase in the degree of deformation to the formation of cracks in the course of upsetting at 900°C. The kinetics of dehydrogenation at the temperatures of 600 and 700°C for 4 h in an argon flow and in vacuum has been studied. The thermohydrogen treatment of the VTI4 alloy makes it possible to obtain a thermostable state with a safe hydrogen content with a predominance of the O phase in the structure and high physical and mechanical properties (the Vickers hardness up to 5300 MPa, the contact modulus of elasticity to 114 GPa) after the final dehydrogenating annealing in the vacuum at 600°C for 4 h.

The influence of the degree of compression in the range of 46–84% upon cold rolling of rods of a biocompatible low-modulus Zr51Ti31Nb18 (IMP BAZALM) alloy preliminarily quenched from the β field on the formation of its structure, phase composition, and physicomechanical properties (hardness, elastic modulus) has been studied by the methods of optical microscopy, transmission electron microscopy, X-ray diffraction analysis, back-scattering electron diffraction, and microindentation. It has been established that with an increase in the degree of compression, a reorientation and elongation of the initially equilibrium β grains occur along the direction of rolling with the formation of a perfect filamentary structure in the rods with a minimum cross-section. The values of microhardness are stabilized in the range of 320–325 HV due to the development of dynamic recovery processes in the deformed structure, and the elastic modulus decreases from 68 to 55 GPa in the rolling plane of rods owing to the improvement of the {001}RP〈110〉RD-type texture, which leads to the appearance of the predominantly “low-modulus” 〈110〉 orientation in the direction of measurement.

The methods of optical and scanning electron microscopy, microhardness measurement, differential scanning calorimetry (DSC), dilatometry, dynamic mechanical analysis, and hydrostatic weighing are used to study the structure and the physical and mechanical properties (density, microhardness, modulus of elasticity, coefficient of linear thermal expansion) of cold-deformed brass LS59-1 in the initial condition and after heating to 800°C. The DSC heating curve exhibits exo- and endothermic effects due to stress relaxation and retrogression (the exothermic effect at 115 – 235°C), melting of lead segregations (the endothermic effect at about 328°C), transition of the β′-phase into a disordered β -condition (the endothermic effect with minimum at 458°C), and transition of the brass into a single-phase β -condition (the endothermic effect at 642 – 747°C with minimum at 721°C).

The currents flowing in metal–CaF2–n-Si and metal–SiO2–CaF2–n-Si structures with the same (about 1.5 nm) fluoride thickness are compared in the reverse-bias mode. It is revealed that the current in the case of a two-layer dielectric can be notably higher within a certain voltage range. Such unexpected behavior is associated with the coexistence of both electron and hole components of the current as well as with the configuration of the SiO2–CaF2 barrier through which tunneling occurs. The results of measurements and explanatory simulation data are presented.

Changes in the structure and phase composition of the high-strength Ti–5Al–5Mo–5V–3Cr alloy after quenching in water and in air from the temperatures of heating corresponding to the β field (in the range of 860–1000°C) and upon subsequent continuous heating have been studied using the methods of optical, scanning, and transmission electron microscopy, X-ray diffraction, microprobe, and thermal analyses, and hardness. It has been shown that the temperature of heating to a significant extent influences the structure of the Ti–5Al–5Mo–5V–3Cr alloy after cooling. In the case of a significant overheating above the temperature of the polymorphic transformation (Tpt +100–150°C), a large amount of vacancies arise, which activate the diffusion processes and promote the appearance of “precipitates” upon cooling in air in the form of single or intersecting packets of very thin plates (with a thickness of 3–5 μm) enriched in Al, Mo, Cr and with a bcc lattice similar to that of the β matrix. Upon subsequent continuous heating, this leads to the inhibition of the decomposition of the metastable matrix β solid solution with the formation of intermediate phases by a homogeneous mechanism and activates the diffusion β → α transformation (as compared to quenching in water), which occurs by the heterogeneous mechanism of decomposition.

The relationship between the phase composition and the Young’s modulus in quenched PT-7M, Ti-6Al-7Nb, BT16 titanium alloys has been studied using the structural analysis, thermodynamic calculations in the Thermo-Calc software and micro-indentation. It is found that the nature of the change in the Young’s modulus in the investigated titanium alloys after quenching from the two-phase α+β-region depends on the chemical composition of the alloy, which determines the nature of the observed metastable phases (α', α", ω, β). The correlation between the extreme change in the Young’s modulus from the quenching temperature and the so-called interatomic bonding force (Fb) calculated from the electronic structure parameters of the α, α', β phases was shown for the Ti-6Al-7Nb alloy. The relationship between the limits of the Young’s modulus of the investigated alloys during quenching with the level of their alloying with α-and β-stabilizers is shown.

Transmission electron microscopy, X-ray diffraction analysis, and microindentation were used to study the changes in the structure, phase composition, elastic modulus, and hardness of the Ti–(9.6–34) at % Nb alloys after quenching in water from heating temperatures corresponding to the β region. The relationship between the physicomechanical properties (elastic modulus, microhardness) and the volume fraction of metastable phases detected in Ti–Nb alloys after quenching from the β region has been shown. It has been noted that the Ti–13.3 at % Nb alloy with a structure in which the ω phase with anomalous morphology in the form of massive plates is formed after quenching is characterized by maximum values of elastic modulus and microdurometric characteristics. The growth of the elastic modulus of the metastable β solid solution with increasing niobium content in alloys with a decrease in the average distance between the niobium–niobium atoms in the bcc structure has been justified. The possibility for calculating the elastic modulus of quenched Ti–Nb alloys based on the additive contributions of the elastic moduli of phases detected after quenching, which are proportional to their volume fractions has been considered.

The evolution of structure, strength and ductile properties of M001 grade copper wire after the coarse and medium drawing were studied using the metallography, micro-indentation and tensile testing. Coefficient for evaluation the ultimate tensile strength from the micro-indentation data was determined. The formula was proposed for estimation the dislocation density the stress strain curves and from the data on the grain size in the transverse section of the wire.

Исследуются последовательности комплексных чисел, удовлетворяющие функциональным соотношениям билинейного типа. Полученные результаты используются для описания всех целых 1-периодических функций $f\colon \mathbb C\to\mathbb C$, удовлетворяющих вместе с некоторыми $\varphi_j,\psi_j\colon \mathbb C\to\mathbb C$ разложению $f(x+y)f(x-y)=\varphi_1(x)\psi_1(y)+…+\varphi_4(x)\psi_4(y)$. Библиография: 38 названий.

In this paper, the formation of the structure, texture, durometric and mechanical properties of the cross section of a hot-extruded tube made of titanium alloy PT-7 M (Ti-2.2Al-2.7Zr, wt%) is considered. The structure, texture and properties of the tube with a diameter of 102 mm and a thickness of 13 mm is determined by the distribution of the temperature over the cross section of the billet during the deformation process. The cooling of the outer surface area of about 2.5 mm of the billet during extrusion to temperatures of the α-region result to the formation of a structure from a predominantly deformed α-phase. Deformation heating during extrusion at a distance of more than 2.5 mm from the outer surface to temperatures near β-transus result to the formation of β-transformed structure with lower strength and higher ductility as compared to the outer near-surface area.

We propose double-gated n-type WSe2 FETs with low leakage, low hysteresis top gate high-k dielectric stack. The top gate dielectric layer is deposited by HfO2 ALD on an Al2O3 seed layer obtained from the evaporation and oxidation by air exposure of a 1.5 nm Al layer. When operated under back gate control, the fabricated WSe2 FETs behave as n-type enhancement transistors with ON/OFF current ratios exceeding 6 orders of magnitude and a ON current close to 1 μA/μm at a drain bias of 100 mV. An applied negative top gate bias determines a much steeper turn-on of the back gated transfer characteristic and a reduction of the observed hysteresis. Top gate devices behave as n-type depletion FETs, reaching a ION/IOFF ratio larger than 106 under positive bias applied to the back gate. The electron mobility, extracted using the Y-function method, was estimated to be 22.15 cm2V-1s-1 under a drain bias of 1 mV. We characterize the hysteresis dynamics in our devices, demonstrating a substantial improvement with respect to comparable top gated MoS2 FETs.

This work is devoted to studying the structure of the northwestern part of the Indian Ocean. Primary materials of the area geological and geophysical survey performed in the southern part of the midoceanic Carlsberg Ridge (research vessel Issledovatel’, PGO Yuzhmorgeologiya, 1987) and results of unique studies of the Equator Ridge (the Somali Basin) from a manned underwater vehicle are used. The Rodrigues block is isolated at the southern extremity of the Carlsberg Ridge, which is anomalous in its morphological characteristics. The conclusion is made that this block is a connecting link of the existed continental bridge between the Seychelles Islands and the Maldive Ridge. It is conjectured that the Carlsberg Ridge was formed on a transitional crust. A complex analysis of all data on the structure of the northwestern Indian Ocean convincingly demonstrates that differentiated tectonic movements were the leading geodynamic factor in its evolution.

The results of the digitalization of the centennial series of solar activity are considered. The data contain information on sunspots since 1918, sunspot umbra since 1917, plages since 1907, and spectral corona since 1939. In particular the digitalization of prominences from the observations in the Ca II K line in 1910–1954 and solar filaments from the observations in the H-alpha line in 1912–2002 acquired at the Kodaikanal Observatory are described. The methods of constructing composite maps of solar activity and presenting the resulting data series on the Internet are described. The long-term variations in solar activity are analyzed.

NICA is a new accelerator complex under construction at JINR in Dubna. For the NICA booster synchrotron and NICA Collider requires more than 390 superconducting magnets. The magnetic system of the booster of NICA project includes 48 quadrupole superconducting magnets. The paper describes a probe designed for series magnetic measurements of the doublet of quadrupole lenses for the booster, as well as methods of measurement. Presents the first results of cryogenic measurements for the two doublets of quadrupole.

The effect of increasing the tunnel current in a metal–calcium fluoride–silicon structure with addition of a silicon dioxide layer between fluoride and metal (which seems paradoxical at first glance) has been considered. This effect of nonmonotonic change in the tunnel conductivity with an increase in the insulator thickness may occur at a relatively high bias at the structure and is related to the tunnel-barrier deformation, at which electrons are tunneling through its part formed by the oxide. At low biases, the occurrence/ thickening of an additional layer leads to a natural decrease in the current. Similar behavior is possible in principle for some other combinations of materials.

Chemical decomposition of DMSO stock solutions is a common incident that can mislead biological screening campaigns. Here, we share our case study of 2‐aminothiazole 1, originating from an antimalarial class that undergoes chemical decomposition in DMSO at room temperature. As previously measured biological activities observed against Plasmodium falciparum NF54 and for the target enzyme PfIspE were not reproducible for a fresh batch, we tackled the challenge to understand where the activity originated from. Solvent‐ and temperature‐dependent studies using HRMS and NMR spectroscopy to monitor the decomposition led to the isolation and in vitro evaluation of several fractions against PfIspE. After four days of decomposition, we successfully isolated the oxygenated and dimerised compounds using SFC purification and correlated the observed activities to them. Due to the unstable nature of the two isolates, it is likely that they undergo further decomposition contributing to the overall instability of the compound., False positive results are unfortunately common in medicinal‐chemistry workflows. The unsuccessful parts of the stories are only rarely shared. In our decomposition study on an antimalarial 2‐aminothiazole, we observed degradation in DMSO. We successfully isolated by SFC and elucidated the structure of decomposition products contributing to the activities against the Plasmodium falciparum NF54 cell line and the target enzyme IspE.

Flavoproteins are important blue light sensors in photobiology and play a key role in optogenetics. The characterization of their excited state structure and dynamics is thus an important objective. Here, we present a detailed study of excited state vibrational spectra of flavin mononucleotide (FMN), in solution and bound to the LOV-2 (Light-Oxygen-Voltage) domain of Avena sativa phototropin. Vibrational frequencies are determined for the optically excited singlet state and the reactive triplet state, through resonant ultrafast femtosecond stimulated Raman spectroscopy (FSRS). To assign the observed spectra, vibrational frequencies of the excited states are calculated using density functional theory, and both measurement and theory are applied to four different isotopologues of FMN. Excited state mode assignments are refined in both states, and their sensitivity to deuteration and protein environment are investigated. We show that resonant FSRS provides a useful tool for characterizing photoactive flavoproteins and is able to highlight chromophore localized modes and to record hydrogen/deuterium exchange.

Identification of solar coronal holes (CHs) provides information both for operational space weather forecasting and long-term investigation of solar activity. Source data for the first problem are typically most recent solar disk observations, while for the second problem it is convenient to consider solar synoptic maps. Motivated by the idea that the concept of CHs should be similar for both cases we investigate universal models that can learn a CHs segmentation in disk images and reproduce the same segmentation in synoptic maps. We demonstrate that Convolutional Neural Networks (CNN) trained on daily disk images provide an accurate CHs segmentation in synoptic maps and their pole-centric projections. Using this approach we construct a catalog of synoptic maps for the period of 2010-20 based on SDO/AIA observations in the 193 Angstrom wavelength. The obtained CHs synoptic maps are compared with magnetic synoptic maps in the time-latitude and time-longitude diagrams. The initial results demonstrate that while in some cases the CHs are associated with magnetic flux transport events there are other mechanisms contributing to the CHs formation and evolution. To stimulate further investigations the catalog of synoptic maps is published in open access.

Nanoelectronic devices based on 2D materials are far from delivering their full theoretical performance potential due to the lack of scalable insulators. Amorphous oxides that work well in silicon technology have ill-defined interfaces with 2D materials and numerous defects, while 2D hexagonal boron nitride does not meet required dielectric specifications. The list of suitable alternative insulators is currently very limited. Thus, a radically different mindset with respect to suitable insulators for 2D technologies may be required. We review possible solution scenarios like the creation of clean interfaces, production of native oxides from 2D semiconductors and more intensive studies on crystalline insulators., The lack of scalable, high-quality insulators is a major problem hindering the progress on electronic devices built from 2D materials. Here, the authors review the current state-of-the-art and the future prospects of suitable insulators for 2D technologies.

Additive manufacturing allows three-dimensional printing of polymeric materials together with cells, creating living materials for applications in biomedical research and biotechnology. However, an understanding of the cellular phenotype within living materials is lacking, which is a key limitation for their wider application. Herein, we present an approach to characterize the cellular phenotype within living materials. We immobilized the budding yeast Saccharomyces cerevisiae in three different photo-cross-linkable triblock polymeric hydrogels containing F127-bis-urethane methacrylate, F127-dimethacrylate, or poly(alkyl glycidyl ether)-dimethacrylate. Using optical and scanning electron microscopy, we showed that hydrogels based on these polymers were stable under physiological conditions, but yeast colonies showed differences in the interaction within the living materials. We found that the physical confinement, imparted by compositional and structural properties of the hydrogels, impacted the cellular phenotype by reducing the size of cells in living materials compared with suspension cells. These properties also contributed to the differences in immobilization patterns, growth of colonies, and colony coatings. We observed that a composition-dependent degradation of polymers was likely possible by cells residing in the living materials. In conclusion, our investigation highlights the need for a holistic understanding of the cellular response within hydrogels to facilitate the synthesis of application-specific polymers and the design of advanced living materials in the future.

Titanium dioxide (TiO2) is one of the most widely used materials in resistive switching applications, including random-access memory, neuromorphic computing, biohybrid interfaces, and sensors. Most of these applications are still at an early stage of development and have technological challenges and a lack of fundamental comprehension. Furthermore, the functional memristive properties of TiO2 thin films are heavily dependent on their processing methods, including the synthesis, fabrication, and post-fabrication treatment. Here, we outline and summarize the key milestone achievements, recent advances, and challenges related to the synthesis, technology, and applications of memristive TiO2. Following a brief introduction, we provide an overview of the major areas of application of TiO2-based memristive devices and discuss their synthesis, fabrication, and post-fabrication processing, as well as their functional properties.

The physicochemical properties of the novel original anxiolytic GML-1 drug substance were studied, analytical techniques for it were developed, and its main pharmacopoeial quality parameters were determined using IR spectroscopy, UV spectrophotometry, HPLC, and the Kjeldahl method.

Until now, FMN/FAD radicals could not be stabilized in aqueous solution or other protic solvents because of rapid and efficient dismutation reactions. In this contribution, a novel system for stabilizing flavin radicals in aqueous solution is reported. Subsequent to trapping FMN in an agarose matrix, light-generated FMN radicals could be produced that were stable for days even under aerobic conditions, and their concentrations were high enough for extensive EPR characterization. All large hyperfine couplings could be extracted by using a combination of continuous-wave EPR and low-temperature ENDOR spectroscopy. To map differences in the electronic structure of flavin radicals, two exemplary proton hyperfine couplings were compared with published values from various neutral and anionic flavoprotein radicals: C(6)H and C(8α)H 3. It turned out that FMN•- in an aqueous environment shows the largest hyperfine couplings, whereas for FMNH• under similar conditions, hyperfine couplings are at the lower end and the values of both vary by up to 30%. This finding demonstrates that protein-cofactor interactions in neutral and anionic flavoprotein radicals can alter their electron spin density in different directions. With this aqueous system that allows the characterization of flavin radicals without protein interactions and that can be extended by using selective isotope labeling, a powerful tool is now at hand to quantify interactions in flavin radicals that modulate the reactivity in different flavoproteins.

The effect of different interstitial impurities content (oxygen, carbon) on β - transus temperature and complex of properties in the heat-strengthened condition of the Ti-5Al-5V-5Mo-3Cr-1Zr (VST55531) titanium alloy has been studied. The possibility of determining alloy β - transus temperature by the differential scanning calorimetry method with accuracy comparable with the test quenching method is shown in this paper. It is shown that under identical aging regimes an increase of oxygen content from 0.176 to 0.25 wt.% and carbon content from 0.009 to 0.025 wt.% in VST55531 alloy results in higher strength, plastic characteristics and lower ductility, toughness characteristics, especially those which related to the crack propagation.

The new technique has been developed for measuring the β-transus temperature of (α+β)-titanium alloys with any initial microstructure by means of the DSC method. The technique is based on a linear correlation between extremums of temperature on the DSC time-derivative curve, the Mo-equivalent of an alloy and the equilibrium β-transus temperature. The developed technique enables the determination of the β-transus temperature with the use of a single specimen and it is characterized by high accuracy comparable with that of structural analysis techniques.

We study the effect of the content of oxygen (carbon) impurities on the temperature of complete polymorphic α + β→β transformation (Tpt) and a set of properties of Ti – 10% V – 2% Fe – 3% Al and VST5553 (Ti – 5% Al – 5% V – 5% Mo – 3% Cr) titanium alloys in the thermally hardened state. We determine the microstructure of the alloys by metallographic analysis and test them for tension and fracture toughness. The dependence of Tpt on the content of impurities in the analyzed alloys is determined. It is shown that the value of Tpt can be found by the method of differential scanning calorimetry whose accuracy is comparable with the accuracy of the method of test quenching. The dependences of the strength and ductile properties of the alloys in tension on the aging temperature are constructed. We also establish the relationship between the fracture toughness of the alloys and the morphology of the primary α-phase.

In this contribution, the relative hyperfine couplings are determined for the 1H nuclei of the flavin mononucleotide (FMN) radical in an aqueous environment. In addition, three structural analogs with different methylation patterns are characterized and the influence of the substituents at the isoalloxazine moiety on the electronic structure of the radicals is explored. By exploiting nuclear hyperpolarization generated via the photo-CIDNP (chemically induced dynamic nuclear polarization) effect, it is possible to study the short-lived radical species generated by in situ light excitation. Experimental data are extracted by least-squares fitting and supported by quantum chemical calculations and published values from electron paramagnetic resonance and electron-nuclear double resonance. Furthermore, mechanistic details of the photoreaction of the investigated flavin analogs with l-tryptophan are derived from the photo-CIDNP spectra recorded at different pH values. Thereby, the neutral and anionic radicals of FMN and three structural analogs are, for the first time, characterized in terms of their electronic structure in an aqueous environment.

Significance In molecular modeling the motion of nuclei, especially hydrogen, cannot be described using the laws of classical mechanics. The importance of nuclear quantum effects has long been appreciated by the ab initio molecular dynamics and by the water simulation communities. However, the vast majority of simulations of biological systems performed at ambient conditions treat atomic motion classically. Even in the new-generation force fields parameterized from quantum mechanics these effects are thought to be minor compared with other inaccuracies at room temperature and pressure. We show that a force field in excellent agreement with quantum mechanical energies and forces will not produce acceptably inaccurate predictions at ambient conditions unless the nuclear motion and interaction are accounted for in the simulation., In many important processes in chemistry, physics, and biology the nuclear degrees of freedom cannot be described using the laws of classical mechanics. At the same time, the vast majority of molecular simulations that employ wide-coverage force fields treat atomic motion classically. In light of the increasing desire for and accelerated development of quantum mechanics (QM)-parameterized interaction models, we reexamine whether the classical treatment is sufficient for a simple but crucial chemical species: alkanes. We show that when using an interaction model or force field in excellent agreement with the “gold standard” QM data, even very basic simulated properties of liquid alkanes, such as densities and heats of vaporization, deviate significantly from experimental values. Inclusion of nuclear quantum effects via techniques that treat nuclear degrees of freedom using the laws of classical mechanics brings the simulated properties much closer to reality.

Transmission electron microscopy and microindentation have been used to study the changes in the structure, phase composition, microhardness, and elastic modulus of the Ti–24.3Al–24.8Nb–1.0Zr–1.4V–0.6Mo–0.3Si (at %) alloy based on the orthorhombic titanium aluminide Ti2AlNb alloyed with hydrogen to 8.5 at % upon aging in the temperature range of 600–700°C after quenching from 900°C. It has been detected that the alloying with hydrogen leads to a change in the morphology of precipitated orthorhombic (O) plates upon aging from a zigzag-shaped to packet morphology and at the aging temperature of 700˚С initiates the transformation of the substructure of the O plates into a polydomain one with the formation of the so-called “polysynthetic twin.” The relationship between the structural characteristics, the amounts of the arising phases, and the values of the microhardness and elastic modulus of the investigated alloys with and without hydrogen after quenching and aging has been established.

Transmission electron microscopy, X-ray diffraction analysis, durometry, and mechanical tensile and impact toughness tests were used to study changes in the structure, phase composition, and mechanical properties in a high-strength VT22I titanium alloy (Ti–3Al–5Mo–5V–1Cr–1Fe) upon isothermal and thermomechanical treatments, including warm rolling and aging. It has been found that the decomposition of the β solid solution in an alloy preliminarily heated in the β region (Тpt + 50°C) after isothermal treatment at 650°C for 1 and 4 min is accompanied by the formation of an intermediate α'' phase; upon holding for 20 min, an equilibrium α phase precipitates. The А7В-type ordering processes, where β stabilizers and aluminum can serve as a B element, are possible and, upon final cooling, in water, the formation of an athermal ω phase can take place at the initial stages of decomposition. It has been shown that the warm rolling of the alloy at 650°C accelerates the processes of the decomposition of the metastable β solid solution, contributes to the refinement of the arising α precipitates, and suppresses the formation of the athermal ω phase upon cooling compared to the similar isothermal treatment without deformation. A regime of a thermomechanical treatment that provides the high mechanical properties required to fabricate elastic structural components has been proposed for this alloy.

Let g be a linear combination with quasipolynomial coefficients of shifts of the Jacobi theta function and its derivatives in the argument. All entire functions f: ℂ → ℂ satisfying f(x+y)g(x−y) = α1(x)β1(y)+· · ·+αr(x)βr(y) for some r ∈ ℕ and αj, βj: ℂ → ℂ are described.

Methods of macro- and microstructural, x-ray structural analyses and mechanical tensile tests of the structure and properties of Ti–3Al–2.5V alloy hot-extruded intended for subsequent cold rolling are studied. Hot-extruded pipe is produced according to the scheme: expansion in a vertical press → extrusion in a horizontal press. It is shown that during sleeve expansion structure and phase structure do not change markedly compared with the initial hot-rolled semi-finished product in two-phase (α+β)-region. Hot extrusion in the recommended temperature range provides formation of a sufficiently homogeneous, well worked macro- and microstructure with a tangential basic texture of α-phase. A set of mechanical properties for hot-extruded pipe of alloy Ti–3Al–2.5V required for performing subsequent cold rolling used in the final stages of pipe preparation by TREX technology is provided.

MoS2 has received a lot of attention lately as a semiconducting channel material for electronic devices, in part due to its large band gap as compared to that of other 2D materials. Yet, the performance and reliability of these devices are still severely limited by defects which act as traps for charge carriers, causing severely reduced mobilities, hysteresis, and long-term drift. Despite their importance, these defects are only poorly understood. One fundamental problem in defect characterization is that due to the large defect concentration only the average response to bias changes can be measured. On the basis of such averaged data, a detailed analysis of their properties and identification of particular defect types are difficult. To overcome this limitation, we here characterize single defects on MoS2 devices by performing measurements on ultrascaled transistors (∼65 × 50 nm) which contain only a few defects. These single defects are characterized electrically at varying gate biases and temperatures....