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Room temperature linear arrays (up to 160 detectors in array) from silicon metal- oxide-semiconductor field-effect transistors (Si-MOSFETs) have been designed for sub- THz (radiation frequency 140 GHz) close to real-time direct detection operation scanner to be used for detection and recognition of hidden objects. For this scanner, the optical system with aspherical lenses has been designed and manufactured. To estimate the quality of optical system and its resolution, the system modulation transfer function was applied. The scanner can perform real-time imaging with the spatial resolution better than 5 mm at the radiation frequency 140 GHz and contrast 0.5 for the moving object speed up to 200 mm/s and the depth of field 20 mm. The average dynamic range of real time imaging system with 160-detector linear array is close to 35 dB, when the sources with the output radiation power of 23 mW (IMPATT diodes) are used (scan speed 200 mm/s). For the system with 32-detector array, the dynamic range was about 48 dB and for the single-detector system with raster scanning 80 dB with lock-in amplifier. However, in the latter case for obtaining the image with the sizes 20×40 mm and step of 1 mm, the average scanning time close to 15 min is needed. Convolutional neural network was exploited for automatic detection and recognition of hidden items.

The article identifies the features of the pathology of the gastrointestinal tract in patients with gastroesophageal reflux disease on the background of hypothyroidism. The frequency of gastroesophageal reflux disease and the severity of this disease increase with age and the presence of comorbid pathology. In the elderly, the frequency of the typical esophageal manifestations decreases, and the erosive esophagitis with atypical symptoms is more common. The growing number of cases of combined thyroid dysfunction with gastropathology requires in-depth study of the reasons for the relationship between these processes. Pathological changes in the gastrointestinal tract in these patients make their condition severer, contributing to the development and progression of metabolic disorders. An important aggravating effect on the regulatory mechanisms of esophageal kinetics has a pathological functioning of the thyroid gland on the background of iodine deficiency. Results and discussion. In patients with gastroesophageal reflux disease with hypothyroidism, all changes in gastric and duodenal function are associated with a decrease in the acid-forming function of the gastric mucosa, due to its atrophy, decreased tone and contractility of the stomach. This in turn leads to a slowing of gastric and duodenal evacuation, dysfunction of the closing capacity of the cardia and, as a consequence, the development of duodenogastroesophageal reflux. The esophageal contents are not so pronounced, so patients with non-erosive forms of esophagitis predominate (46.2%) against 16% of patients in the second group (patients with gastroesophageal reflux disease). At the same time, erosive forms predominate among patients in the control group with predominant acid reflux. It should be noted that there is a clear relationship between the frequency of erosive changes in the esophageal mucosa and the duration of the disease. Thus, among patients of the main group with a 5-year history of the disease, the number of erosive forms of gastroesophageal reflux disease was minimal. The number of erosive changes in the esophageal mucosa increased sharply in patients with a 10-year history and reached its maximum after 15 years from the onset of the disease. Conclusion. The delay in gastric evacuation is more pronounced in patients with gastroesophageal reflux disease on the background of hypothyroidism. It can be explained by a decrease in gastric motility and the presence of duodenostasis. The slowing of gastric evacuation was more pronounced in patients with gastroesophageal reflux disease on the background of reduced thyroid function. In patients with gastroesophageal reflux disease on the background of hypothyroidism there is an alkaline duodenogastroesophageal reflux as a consequence of reduced acid-forming function of the gastric mucosa and reduced contractility of the stomach and duodenum

The absorption of electromagnetic radiation by a composite based on bimetallic nanoparticles with a “core–shell” type of structure has been analyzed using the Maxwell–Garnett theory. Expressions have been obtained for the real and imaginary parts of the dielectric function of a two-layered particle in the limiting cases of “thick” and “thin” shells. It has been established that the presence of two metals in the composition of the inclusions leads to a splitting of the maxima and minima in the frequency dependences of the dielectric function and of the coefficient of absorption of the nanocomposite. The frequency dependences of the real and imaginary parts of the dielectric function and of the coefficient of absorption of the composite with bimetallic nanoparticles of different metals have been calculated. An essential influence of both the geometric characteristics of the particles-inclusions and of their composition on the optical properties of the composite has been revealed.

In recent years, significant progress has been made in the treatment of severe injuries and traumas. In critical situations, for the heaviest category of wounded, the outcome is largely determined in the next few minutes after admission to the hospital. The only possible tactic that gives a chance to save the lives of such victims is the tactics of multi-stage surgical treatment (damage control). The low effectiveness of traditional methods of training surgeons in the basics and techniques of this tactic makes it necessary to develop new forms of training. One of the most progressive and sought-after is training on biological material (large animals or cadaver material), but the methodology for conducting such studies has not been worked out before. For the first time in Russia in November 2018, a unique training and practical course «SMART» (Modern Methods and Algorithms for the Treatment of Wounds and Traumas) was conducted, combining training in both living tissues and cadavers. Participants were given the opportunity to see and independently work out the basic combinations of typical surgical techniques and maneuvers aimed at eliminating the life-threatening consequences of injuries and traumas.

The optical properties of spherical metal–oxide nanoparticles were studied in the framework of the Drude theory. Frequency dependences of the real and imaginary parts of the dielectric constant, coherence loss parameter, and absorption coefficient of bilayer Ag, Al, and Cu nanoparticles of radii 10–30 nm in various matrices were calculated. The behavior of the frequency dependences of the imaginary part of the dielectric constant and absorption coefficient at low frequencies was determined by the contribution of electron surface-scattering mechanisms.

Clinical Center of Stomatology of FMBA of Russia, 123098, Moscow, Russian FederationDental morbidity in childhood is practically not reduced. The effectiveness of preventive measures is great in early childhood, and therefore relevant research on the epidemiology of the prevalence and intensity of caries and gingivitis in children 6-9 years. Surveyed 176 people at the school of Moscow and the indicators of dental disease and treatment needs among schoolchildren 6 to 9 years. In Moscow, the prevalence of caries - 92,0%, periodontal disease - 19,3% with intensity of 1,67±0,03 (CPU) and 0,53±0,03 (CPI), respectively, with satisfactory and good oral hygiene in 81,1% of the surveyed children is high in the period of a change bite. The need for dental treatment in the examined patients has a structure: in the treatment of caries - 32,4%, in the removal of teeth - 15,3%, in professional hygiene - 19,8%, in the preventive sealing of fissures - 34,1%. The total need for dental and periodontal sanitation was 52.8%.

The paper presents a method of fabrication and a comparison of the characteristics of obtained cemented carbide samples based on tungsten carbide with 10% metal binder. They were synthesized by spark plasma sintering (SPS) at different sintering temperatures: Co (1200 °C), Fe and Ni (1150 °C), Cr (1500 °C), and Ti (1400 °C). During the SPS-consolidation process, investigations of the dilatometric characteristics of samples of starting powders of identical granulometric composition obtained by mixing/grinding resulting in the fractional composition in the particle size range up to 10 μm are presented. The mechanism of phase formation and microstructure of the obtained materials is investigated by XRD, SEM, and EDS. The possibility of synthesizing hard alloys WC – 10%Ti and WC – 10% Cr by the mechanism of reaction SPS synthesis with a reduction in the synthesis time in comparison with traditional sintering methods has been demonstrated. Analyses have shown that during sintering of alloys containing Ti and Cr the volume content of WC decreases to 47% because of dissolution and interaction, while in alloys containing Co, Ni, and Fe, the volume content of WC remains unchanged (85–86%). This led to a dramatic change in hardness, fracture toughness, and strength when replacing Co, Ni, or Fe with Ti or Cr.

Frequency dependences have been obtained for the real and imaginary parts and the absolute values of the components of the polarizability tensor of metal-oxide nanowires, as well as for the absorption and scattering cross-sections. The limiting cases of the ‘thick ” and “thin ” outer oxide layers are studied. Numerical calculations are performed for Al, Cu, and Ag wires coated with a corresponding oxide layer. The models where the dielectric constant of an oxide is either a constant or a function of the frequency are considered. In the last case, experimental frequency dependences of the refractive and extinction indices are used. The influence of the oxide layer thickness on the frequency dependences of the polarizability and the absorption and scattering cross-sections is analyzed. It is found that the presence of an oxide leads to a decrease in the frequency of surface plasmons in two-layer nanowires due to the influence of classical size effects., В роботi одержано спiввiдношення для частотних залежностей дiйсної й уявної частин та модуля компонентiв тензора поляризовностi, а також перерiзiв поглинання i розсiювання метал-оксидних нанодротiв. Дослiджено граничнi випадки “товстого” I “тонкого” зовнiшнього шару оксиду. Чисельнi розрахунки проведено для дротiв Al, Cu i Ag, вкритих шаром власного оксиду. Розглянуто випадки, коли дiелектрична проникнiсть оксиду є постiйною величиною або є функцiєю частоти. В останньому випадку для визначення цiєї залежностi було використано апроксимацiю експериментальних кривих частотних залежностей показникiв заломлення та екстинкцiї. Проаналiзовано вплив змiни товщини оксидного шару на поведiнку частотних залежностей поляризовностi i перерiзiв поглинання i розсiювання. Встановлено, що наявнiсть оксиду приводить до зменшення частоти поверхневих плазмонiв у двошарових нанодротах внаслiдок впливу класичних розмiрних ефектiв.

The sensitivity and basic electrical characteristics of the developed direct illumination matrices with charge-coupled devices and electronic multiplication were investigated at room temperatures and low illumination. Photomatrices of 576´288 and 640´512 format were designed using frame transfer architecture and 1.5-µm design rules with photosensitive cell sizes of 20´30 and 16´16 µm, respectively, and manufactured using n-channel technology with buried channel, four levels of polysilicon electrodes and two levels of metallization. To analyze the possibilities of the developed EMCCD matrices used in monitoring systems at low-light conditions, an experimental assessment of the matrices sensitivity was carried out. The assessment was based on a comparison of the luxmeter readings and Johnson's criteria using the standard 1951 USAF resolution target test table for the minimum size of line pairs distinguished by the observer (one pair consists of a dark and a light lines). The characteristics obtained with illumination of 5∙10–4 lux (glow of the starry sky with light clouds) and 10–2 lux (glow of the starry sky and the quarter of the Moon) corresponds to the parameters of generation 2+ electron-optical converters, which implies the possibility to use such matrices in night vision devices. At Åv ≈ 5∙10–4 lux, the camera with the developed EMCCD matrices will detect a human figure at the distance of about 200 m. With illumination of 10–2 lux at this distance a human figure can be identified.

Проаналізовано можливість використання розігріву біологічних тканин при збудженні поверхневих плазмонів у двошарових сферичних метал-графенових наночастинках для термодеструкції злоякісних новоутворень. Для визначення частотних залежностей діелектричної функції металевого ядра і провідності графенової оболонки використано моделі Друде і Кубо, відповідно, а розподіли температури в тканинах пухлини та оточуючих її здорових тканинах визначаються розв’язками неоднорідних рівнянь теплопровідності. Для чисельних оцінок і розрахунків використано відомі з літератури значення теплофізичних параметрів тканин пухлини і здорових тканин людини. Досліджено еволюцію частотних залежностей поляризовності і перерізів поглинання вказаних наночастинок при зміні радіусу і матеріалу металевого ядра і товщини графенової оболонки. Показано, що зі збільшенням радіусу металевого ядра або товщини графенової оболонки відбувається зростання максимальних значень уявної частини поляризовності і перерізу поглинання, що пов’язано з підсиленням взаємодії з електромагнітною хвилею зі збільшенням об’ємного вмісту металу у композитній наночастинці і високою концентрацією вільних електронів у графенових шарах. Продемонстровано можливість спектральних зсувів максимумів поляризовності і перерізу поглинання при зміні матеріалу ядра двошарової наночастинки внаслідок суттєвої різниці у значеннях частот об’ємних плазмонів і внеску іонного остову в діелектричну функцію. Встановлено, що теплопровідність в задачі про нагрівання біологічних тканин при збудженні поверхневого плазмонного резонансу у композитній наночастинці є квазістаціонарною. Доведено, що даний метод терапії раку є нешкідливим для здорових тканин, що оточують пухлину, внаслідок їх вкрай незначного нагрівання. Результати чисельного моделювання свідчать про необхідність застосування конгломерату метал-графенових наночастинок з метою підвищення ефективності терапії. The possibility of using heating of body tissue upon excitation of surface plasmons in two-layer spherical metal-graphene nanoparticles for thermal destruction of malignant neoplasms has been analyzed. Drude and Kubo models have been used to determine the frequency dependences of the dielectric function of the metal core and the conductivity of the graphene shell, respectively, and the distributions of temperatures in tumor tissue and surrounding healthy tissue have been determined by solutions of nonhomogeneous thermal conductivity equations. Values of thermophysical parameters of tumor tissue and healthy human tissue known from the literature have been used for numerical estimates and calculations. The evolution of the frequency dependences of the polarizability and absorption cross-sections of the indicated nanoparticles with the variation of the radius and material of the metal core and the thickness of the graphene shell has been studied. It has been shown that an increase in the radius of the metal core or thickness of the graphene shell results in an increase in the maximum values of the imaginary part of the polarizability and absorption cross-section, which is associated with increased interaction with the electromagnetic wave with increasing bulk metal content in the composite nanoparticle and with high concentration of free electrons in graphene layers. The possibility of spectral shifts of the polarizability maxima and the absorption cross-section with the variation of the core material of a two-layer nanoparticle, due to the essential difference in the values of the frequencies of bulk plasmons and the contribution of the ion core to the dielectric function, has been demonstrated. It has been established that the thermal conductivity is quasi-steady in the problem of heating of body tissue upon excitation of surface plasmon resonance in a composite nanoparticle. It has been proved that this method of cancer therapy is harmless to healthy tissue surrounding the tumor due to their extremely low heat. The results of numerical modeling demonstrate the need to use a conglomerate of metal-graphene nanoparticles in order to increase the effectiveness of therapy.

A sub-THz/THz radiation detector device based on Si-MOSFET has been presented. Si-MOSFET source and gate connected to an antenna serves as a detector element. Geometry of the Si-MOSFET antenna, principle of device operation, method of estimating the sensitivity and noise equivalent power (NEP) have been described. A removable system of aspheric lenses has been developed and made for this detector device, a measured point spread function of the system of aspheric lenses has been given at the frequency 140 GHz. The detector device has been tested at the same frequency; sensitivity and NEP of the detector device have been estimated and they are equal to S=2.8×105 V/W, NEP=4.3×10-10 W (Hz)-1/2, accordingly.

In terms of the model of stable jellium, self-consistent calculations of spatial distributions of electrons and potentials, as well as of energies of dissociation, cohesion, vacancy formation, electron attachment, and ionization potentials of solid clusters of Mg N , Li N (with N ≤ 254 ) and of clusters containing a vacancy (N ≥ 12) have been performed. The contribution of a monovacancy to the energy of the cluster and size dependences of its characteristics and of asymptotics have been discussed. Calculations have been performed using a SKIT-3 cluster at Glushkov Institute of Cybernetics, National Academy of Sciences, Ukraine (Rpeak = 7.4 Tflops).

The calculations of labor intensity and cost of prevention of dentoalveolar anomalies in children with premature loss of teeth using a removable plate with artificial teeth. The method of calculations is described in detail, the differentiated values of labor intensity and cost of different stages of production of the plate and its use are given. The complexity of manufacturing a removable plate with artificial teeth and the corresponding observation by an orthodontist doctor in the process of preventing deformation in a child with premature loss of temporary teeth is an average of 7.5 hours; direct labor costs of the doctor are 4.3 hours, dental technician-1.9 hours. The cost of production of the plate and subsequent treatment is 13 370 rubles, among which 80% is the remuneration of the main and auxiliary personnel with tax charges.

The article presents the results of the analysis of orthodontic status in 176 children 6-9 years with a removable bite in Moscow. The high prevalence of dentoalveolar anomalies among children with a removable bite in Moscow (73.9 %), including anomalies in the position of the teeth (67.0%) and the ratio of dental arches (67.6 %). Significant detection of premature loss of temporary teeth (17.0 %). In the structure of anomalies of the teeth position the crowding of the teeth (45,2 %) is most represented, and among the anomalies of the ratio of dental arches - distal and excessively deep bites (respectively 46,0 % and 21 %).

It was established that structure modifications of carbon, received resulting from pyrolysis plant material and ash of natural graphite are the limiting factors when implementing the mechanochemical synthesis of titanium carbide in a vibratory treatment. The shown prospects of using natural graphite and modifications of the structure amorphous carbon, made from vegetable raw materials for the synthesis of titanium carbide with a minimum sulfur content. Ill. 6. Ref. 12. Tab. 1.

Electron multiplication charge coupled devices (EMCCD) technology is an innovation first introduced slightly more than a decade ago. The EMCCD is an image sensor that is capable of detecting an isolated photon without an image intensifier. It is achieved by electron multiplication circuit that is built in the chip of ordinary CCD. Cameras with EMCCD arrays overcome limitations of getting high sensitivity with high frame rate. Traditional CCD cameras can be highly sensitive in the visible part of spectrum but at the expense of low frame rate. EMCCD can operate at very faint illumination conditions both in visible and near infrared regions. The paper presents a short technological description of EMCCD 640×512 arrays manufacturing and some parameters of the arrays that were designed and manufactured. It was shown that multiplication coefficient depends much on applied amplification voltage and can achieve 1000. Also it is shown that images can be obtained at low illumination conditions (illumination at EMCCD is near 5∙10–4 lx).

Production aspects are provided for manufacturing sintered tungsten-cobalt alloy VK8 based on tungsten carbide prepared by mechanochemical synthesis. It is shown that experimental alloy VK8 physicomechanical, and operating properties significantly exceed those of commercial grade hard alloy, which opens up possibilities for its use in preparing cutting, drilling, and also stamping tools operating under dynamic conditions.

The mechanism of dispersion of metals in the presence of high molecular compounds is shown on the example of grinding high speed R6M5 steel swarf. It was shown that metal pulverization is more energetically favorable in the presence of a mechanically degradable polymer than in the presence of low-molecular weight surfactants.

The probabilities of the localization of positrons in monovacancies of Al and Cu have been calculated as functions of the energy and temperature. The vacancy was simulated by a void with a radius equal to the radius of the Wigner—Seitz cell in the model of stable jellium. Using the Fermi—Dirac golden rule for transitions, the formula for the rate of positron trapping by a vacancy has been derived as the function of the positron energy. For the thermalized positrons, the rate of localization near the triple point proved to be, on the order of magnitude, close to the rate of annihilation. Within the framework of our previously proposed models, the contribution of vacancies to the work function of electrons and positrons has been demonstrated based on the example of Al. The physical situations where the vacancy effect can manifest have been considered.

This paper presents a method for producing a hard alloy WC-5TiC-10Co with a density equal to 100% of the theoretical value, a hardness of 1484 HV, and a bending strength limit of 1924 MPa. The high quality of the product is ensured by original research method based on the mechanochemical synthesis of WC and TiC powders using available precursors. and the implementation of high-speed SPS consolidation of the obtained powder while achieving a high degree of packaging with a minimum grain growth at 1200 °C and processing time no more than 13 min. Experimental data on seal dynamics, phase composition, morphology and mechanical properties of WC-5TiC-10Co using SPS in the range 1000 to1200 °C are presented.

This article describes the developed equipment that allows measuring the photoelectrical parameters of multielement photodetectors, specifically various formats of EMCCD (electron multiplying charge-coupled device) chips. The authors present the measuring techniques and test results on dark currents, output amplifier sensitivity, charge transfer efficiency, charge capacity and other parameters. The studies were conducted, both on the wafer and in the body, on samples of the following formats: 576×288, 640×512, 768×576, 1024×1024, and 1280×1024. В данной статье описывается разработанное оборудование, позволяющее измерять фотоэлектрические параметры многоэлементных фотоприемников, в частности, различных форматов микросхем ПЗСЭУ (приборы с зарядовой связью и электронным умножением). Представляны методы измерения и результаты испытаний на темновые токи, чувствительность выходного усилителя, эффективность переноса заряда, зарядную емкость и другие параметры. Исследования проводились на образцах следующих форматов: 576×288, 640×512, 768×576, 1024×1024 и 1280×1024, как на пластине, так и в корпусе. В даній статті описано розроблену вимірювальну систему, що дозволяє досліджувати фотоелектричні параметри багатоелементних фотоприймачів, зокрема ПЗЗЕМ різних форматів. Представлено методики та результати вимірювань темнових струмів, чутливості вихідного підсилювача, ефективності передачі заряду, зарядової ємності та інших параметрів. Дослідження проводилися на зразках формату 576×288, 640×512, 768×576, 1024×1024, 1280×1024 як на пластинах, так і в корпусах.

Radial distributions of electron concentration and electrostatic potential in perfect clusters and clusters with a centered monovacancy have been calculated self-consistently in the framework of the stabilized jellium model and using the Kohn–Sham method, which allowed the total energy of neutral and charged clusters containing a defect to be determined for the first time. On the basis of the results obtained, the dissociation, cohesive, and monovacancy formation energies, the electron affinity, the ionization potential, and the electric capacitance are directly calculated. The results of numerical calculations for Na, Mg, and Al are compared with asymptotic dependences and with the results obtained for defect-free clusters. The quantum-size dependences of the energy of monovacancy formation driven by either the Schottky or the “bubble blowing” mechanism, as well as their asymptotics, are determined. Strong fluctuationsof this quantity as a function of the cluster size are revealed. The asymptotic dependences obtained for two indicated mechanisms are shown to differ from each other, but depend weakly on the number of atoms in a cluster., Методом Кона–Шема у моделi стабiльного желе виконано самоузгодженi розрахунки профiлiв радiальних розподiлiв електронiв та потенцiалiв суцiльних кластерiв i кластерiв iз центрованою моновакансiєю. Це дозволило вперше одержати повну енергiю нейтральних та заряджених дефектних кластерiв, на основi чого проведено прямi розрахунки енергiй дисоцiацiї, когезiї, утворення вакансiї, спорiдненостi до електрону, потенцiалу iонiзацiї, а також електричної ємностi. Результати чисельних розрахункiв для кластерiв Na, Mg i Al порiвнюються з асимптотиками i результатами для бездефектних кластерiв. Розраховано квантово-розмiрнi залежностi енергiї утворення вакансiї за механiзмами Шотткi i “видування пухирця” i визначено їх асимптотичну поведiнку. Виявлено сильнi розмiрнi флуктуацiї енергiї утворення вакансiї в усiй областi розмiрiв кластерiв. Показано, що розмiрнi асимптотики цих двох механiзмiв вiдрiзняються одна вiд одної i слабко залежать вiд числа атомiв у кластерi. Обчислення проводилися на кластерi СКIТ-3 Iнституту кiбернетики iм. В.М. Глушкова НАН України (Rpeak = 7,4Tflops).

Ferrofluid heating by an external alternating field is studied based on the rigid dipole model, where the magnetization of each particle in a fluid is supposed to be firmly fixed in the crystal lattice. Equations of motion, employing the Newton's second law for rotational motion, the condition of rigid body rotation, and the assumption that the friction torque is proportional to angular velocity, are used. This oversimplification permits us to expand the model easily: to take into account the thermal noise and inter-particle interaction that allows to estimate from unified positions the role of thermal activation and dipole interaction in the heating process. Our studies are conducted in three stages. The exact expressions for the average power loss of a single particle are obtained within the dynamical approximation. Then, in the stochastic case, the power loss of a single particle is estimated analytically using the Fokker-Planck equation and numerically using the effective Langevin equation. Finally, the power loss for the particle ensemble is obtained using the molecular dynamics method. Here, the local dipole fields are calculated approximately based on the Barnes-Hut algorithm. The revealed trends in the behaviour of both a single particle and the particle ensemble suggest the way of choosing the conditions for obtaining the maximum heating efficiency. The competitiveness character of the inter-particle interaction and thermal noise is investigated in details. Two situations, when the thermal noise rectifies the power loss reduction caused by the interaction, are described. The first of them is related to the complete destruction of dense clusters at high noise intensity. The second one is originated from the rare switching of the particles in clusters due to thermal activation, when the noise intensity is relatively weak., 17 pages 11 figures

We study theoretically large metal clusters containing vacancies. We propose an approach, which combines the Kohn-Sham results for monovacancy in a bulk of metal and analytical expansions in small parameters $c_{v}$ (relative concentration of vacancies) and $R_{N,v}^{-1}$, $R_{N,v}$ being cluster radius. We obtain expressions of the ionization potential and electron affinity in the form of corrections to electron work function, which require only the characteristics of 3D defect-free metal. The Kohn-Sham method is used to calculate the electron profiles, ionization potential, electron affinity, electrical capacitance, dissociation, cohesion and monovacancy-formation energies of the small perfect clusters Na$_{N}$, Mg$_{N}$, Al$_{N}$ ($N \leq 270$) and the clusters containing a monovacancy ($N\geq 12$) in the stabilized-jellium model. The quantum-sized dependences for monovacancy-formation energies are calculated for the Schottky scenario and the "bubble blowing" scenario, and their asymptotic behavior is also determined. It is shown that the asymptotical behaviors of size dependences for these two mechanisms differ from each other and weakly depend on the number of atoms in the cluster. The contribution of monovacancy to energetics of charged clusters, the size dependences of their characteristics and asymptotics is discussed. It is shown that difference between the characteristics for the neutral and charged cluster is entirely determined by size dependences of ionization potential and electron affinity. Obtained analytical dependences may be useful for the analysis of the results of photoionization experiments and for the estimation of the size dependences of the vacancy concentration including the vicinity of the melting point., 20 pages, accepted for publications in Journal of Chemical Physics

Carbon nanotubes have been formed as a result of mechanical activation of amorphous carbon obtained after the pyrolytic treatment of brown sphagnum moss. The yield of nanotubes grows from 8 to 75 wt % with increasing the time of mechanical activation from 4 to 27 h. An integrated study of the adsorption properties of carbon materials obtained from sphagnum moss is presented. It is shown that the capability of the oxidative modification of carbon nanotubes depends on the parameters of the formation process, and the efficiency of adsorption capacity is a function of the storage time of the carbon material. The potential of carbon materials obtained from sphagnum moss as enterosorbents is considered.

It is found that the main factors determining the synthesis parameters of tungsten carbide by mechanically stimulated thermal explosion are the structure of carbon modifications and the degree of their aromaticity. The prospects of using carbon modifications obtained from plant raw materials for the synthesis of tungsten carbide with a low content of sulfur are discussed.

It is shown that multilayer carbon nanotubes, formed using pyrolytic treatment and mechanical activation for amorphous carbon prepared from different plant raw materials, exhibit high sorption capacity with respect to hydrogen.

The possibility is considered of using multilayer carbon nanotubes prepared from brown Sphagnum for modifying epoxy resin. It is established that epoxy composite modified with carbon nanotubes makes it possible to provide improved composite material mechanical properties.

Complex studies of the sorptive properties of carbon materials obtained from regenerative vegetable raw materials have been made. The possibility of using such materials as enterosorbents has been considered.

We have studied the sorption properties of nanofibrous carbon (multiwalled nanotubes) produced by milling amorphous carbon prepared through sphagnum moss pyrolysis. The results demonstrate that the sorption capacity of the carbon nanotubes depends on storage time and that their oxidation behavior depends on nanotube preparation conditions.

Two nanocomposite systems—amorphous carbon + nanoparticulate silicon and nanofibrous carbon + nanoparticulate tungsten—have been fabricated from vegetable and mineral raw materials: sphagnum moss, field horsetail, and scheelite. We examine the possibility of using the nanocomposite systems as anode electrodes of lithium-ion polymer batteries.

An energy-saving technology for production of variously structured carbon modifications from a renewable vegetable raw material, i.e., the waste of agricultural crops and peat moss, has been developed. Promising functional materials — refractory compounds (tungsten and titanium carbides) and oil sorbents possessing a combination of high operating characteristics — have been formed on the basis of the synthesized carbon modifications.

It is shown that carbon nanotubes are formed with mechanochemical treatment of amorphous carbon, obtained by pyrolysis from brown sphagnum. Comprehensive studies are presented for sorption properties of carbon material prepared from sphagnum moss. It is established that the capacity for oxidation modification depends on nanotube formation production parameters, and carbon nanotube sorption capacity efficiency depends on the storage duration.