Diffusion of Sn in polycrystalline α-Fe under pulsed magnetic field

The experimental investigations of Sn diffusion in ferromagnetic α-Fe within the pulsed magnetic field by X-ray diffraction analysis were performed. The pulsed magnetic field was found to influence significantly the diffusion coefficients of Sn in α-Fe

Experimental Studies of Mechanical-Electrical Transformations during the Destructive Processes Developing in Dielectric Materials

A mechanical-electrical method for testing fractures developing within the stress-strain state changes of dielectric rock samples, as an example, is discussed here. The paper discusses the results of numerical and experimental studies of changes in the electromagnetic responses parameters under the pulse deterministic acoustic excitation of rock samples with different composition and texture. The paper presents the results of mathematical calculations of the stress concentration on cracks located along and across the sample axis, perpendicular to which deterministic acoustic pulses were introduced. The cracks presented in the sample volume are stress concentrators. With a different number and sizes of cracks perpendicular to the propagation of an acoustic pulse, the intensity of stresses and their type differ significantly. This circumstance indicates the influence of the structure of the samples and their dielectric properties on the parameters of electromagnetic signals when recording the results of mechanical and electrical transformations. Thus, the use of the method of mechanical-electrical transformations under compression can be used in testing the processes of the onset of crack formation and the development of fracture in solid-state dielectric materials and products

Drastic changes in the distribution of branched tetraether lipids in suspended matter and sediments from the Yenisei River and Kara Sea (Siberia): Implications for the use of brGDGT-based proxies in coastal marine sediment

The distribution of branched glycerol dialkyl glycerol tetraethers (brGDGTs) in soils has been shown to correlate with pH and mean annual air temperature. Because of this dependence brGDGTs have found an application as palaeoclimate proxies in coastal marine sediments, based on the assumption that their distribution is not altered during the transport from soils to marine systems by rivers. To study the processes acting on the brGDGT distributions, we analysed the full suite of brGDGTs, including the recently described 6-Me brGDGTs, in both the suspended particulate matter (SPM) of the Siberian Yenisei River and the SPM and sediments of its outflow in the Kara Sea. The brGDGT distribution in the SPM of the Yenisei River was fairly constant and characterized by high abundances of the 6-Me brGDGTs, reflecting their production at the neutral pH of the river water. However, the brGDGT distribution showed marked shifts in the marine system. Firstly, in the Yenisei River Mouth, the fractional abundance of the 6-Me brGDGTs decreases sharply. The brGDGT signature in the Yenisei River Mouth possibly reflects brGDGTs delivered during the spring floods that may carry a different distribution. Also, coastal cliffs were shown to contain brGDGTs and to influence especially those sites without major river inputs (e.g. Khalmyer Bay). Further removed from the river mouth, in-situ production of brGDGTs in the marine system influences the distribution. However, also the fractional abundance of the tetramethylated brGDGT Ia increases, resulting in a distribution that is distinct from in-situ produced signals at similar latitudes (Svalbard). We suggest that this shift may be caused by preferential degradation of labile (riverine in-situ produced) brGDGTs and the subsequent enrichment in less labile (soil) material. The offshore distribution indeed agrees with the brGDGT distribution encountered in a lowland peat. This implies that the offshore Kara Sea sediments possibly carry a soil-dominated signal, indicating potential for palaeoclimate reconstructions at this site.Both in the river system and coastal cliffs, brGDGTs were much more abundant than crenarchaeol, an archaeal isoprenoid GDGT, resulting in high (>0.93) Branched and Isoprenoid Tetraether (BIT) index values. Moving downstream in the marine sediments, a decrease in brGDGT concentrations, coeval with an increase in crenarchaeol, resulted in decreasing BIT index values. This decrease correlates with changes in bulk proxies for terrigenous input (d13Corg, C/N), confirming the use of the BIT index to trace the delivery of river-transported and coastal cliff-derived terrigenous organic matter

Triggering pulse generators developed for the high-voltage dischargers of magnetic systems and for the generator of pulse voltages used by the relativistic electron beam accelerator "TEMP-B"

The pulse generators were developed to trigger the high-voltage dischargers of magnetic systems and the dischargers of the generators of pulsed voltages used by the relativistic electron beam (REB) accelerator “TEMP-B”. The description of the triggering pulse generators designed by the NSC KIPT to actuate the dischargers of the pulsed voltage generators (PVG) and the dischargers of magnetic systems has been given. These are used by the commutation systems of capacitor banks with the stored energy margin in the range of 60 to 150 kJ. The generators provide the generation of voltage pulses with the amplitude of up to 20 kV.Розроблено генератори імпульсів для запуску високовольтних розрядників магнітних систем і генератора імпульсних напруг прискорювача релятивістських електронних пучків (РЕП) «ТЕМП-Б». Приведено опис генераторів і розглянута їх робота з розрядниками, спроектованими в ННЦ ХФТІ, які використовуються в системах комутації конденсаторних батарей з енергетичним запасом від 60 до 150 кДж. Генератори забезпечують отримання імпульсів напруги з амплітудою до 20 кВ.Разработаны генераторы импульсов для запуска высоковольтных разрядников магнитных систем и генератора импульсных напряжений ускорителя релятивистских электронных пучков (РЭП) «ТЕМП-Б». Приведено описание генераторов и рассмотрена их работа с разрядниками, спроектированными в ННЦ ХФТИ, которые используются в системах коммутации конденсаторных батарей с энергетическим запасом от 60 до 150 кДж. Генераторы обеспечивают получение импульсов напряжения с амплитудой до 20 кВ

Monitoring the capacitor charge voltage in the pulse voltage generator using the accelerator of relativistic electron beams

Noise-protected high charge voltage meter was manufactured using terminal capacitors of the four-channel pulse voltage generator (PVG). The noise protection is provided by the use of communication lines with fiberoptic cables. This measuring device is successfully used for the relativistic electron beam (REB) accelerator “Temp-B” and it provides the measurement accuracy of ~ 0.5% in the electromagnetic noise environment.Виготовлений перешкодозахищений вимірювач високої зарядної напруги на кінцевих конденсаторах чотириканального генератора імпульсної напруги (ГІН). Перешкодозахищеність забезпечується застосуванням ліній зв'язку з використанням оптоволоконного кабеля. Даний вимірювач успішно використовується на прискорювачі РЕП «Темп-Б» і забезпечує точність вимірювання ~ 0,5% в умовах сильних електромагнітних перешкод.Изготовлен помехозащищенный измеритель высокого зарядного напряжения на оконечных конденсаторах четырехканального генератора импульсного напряжения (ГИН). Помехозащищённость обеспечивается применением линий связи с использованием оптоволоконного кабеля. Данный измеритель успешно применяется на ускорителе РЭП «Темп-Б» и обеспечивает точность измерения ~ 0,5% в условиях сильных электромагнитных помех

High-throughput ab-initio calculations: materials for energy storage

At present time, sodium-based batteries are considered as the most viable candidates for replacing widespread lithium batteries. Al- and K-based materials (among others) are also envisaged as prospective compounds for the next generation of solid state batteries (SSB). We are calculated the possible migration pathways for a number of Na-, Al-,K- and Li-conductive materials and selected new perspective compounds from ICSD database using ToposPro package, specially designed for study of super-ionic conductors. For the most promising compounds a careful analysis using DFT calculations was performed. The combined study with both topological and DFT approaches is crucial to gain insight into the main features of ionic conductivity

Diagnostic module for the radiation beam system “TEMP-B”

The power module designed for the calibration and adjustment of the units and components of microsecond accelerator of relativistic electron beams (REB) “Temp-B” has been developed and manufactured. The noise immune gauge of high charging voltages of the terminal capacitors used by four-channel pulse voltage generator (PVG) and the discharger operating in the broad band of charging voltages have been manufactured. The methods developed using the module and the manufactured noise immune gauge of high charging voltages were applied to the accelerator “Temp-B”.Разработан и изготовлен силовой модуль для калибровки и отладки узлов и элементов микросекундного ускорителя релятивистских электронных пучков (РЭП) “Темп-Б”. Изготовлены помехозащищённый измеритель высокого зарядного напряжения на оконечных конденсаторах четырёхканального генератора импульсного напряжения (ГИН) и разрядник, работающий в широком диапазоне зарядных напряжений. Разработанные на модуле методики и изготовленный помехозащищённый измеритель высокого зарядного напряжения применены на ускорителе “Темп-Б”.Розроблено та виготовлено силовий модуль для калібрування і налагодження вузлів та елементів мікросекундного прискорювача релятивістських електронних пучків (РЕП) “Темп-Б”. Виготовлено перешкодозахищений вимірювач високої зарядної напруги на кінцевих конденсаторах чотириканального генератора імпульсної напруги (ГІН) та розрядник, що працює в широкому діапазоні розрядних напруг. Розроблені на модулі методики і виготовлений перешкодозахищений вимірювач високої зарядної напруги застосовані на прискорювачі “Темп-Б”

Long- and short-term earthquake prediction in Kamchatka

This paper presents the results of long- and short-term earthquake prediction obtained during 1971–1974. They can be summarized as follows: The map of long-term prediction for the Kurile—Kamchatka zone compiled in 1965 and supplemented in 1972 by S.A. Fedotov is in good agreement (in four of four possible cases) with recorded seismicity. The results obtained allow us to suppose that the areas for which the log (Ep/Es) of small earthquakes is low may be the areas of future large earthquakes. Prediction of active periods for the Kamchatka earthquakes with M > 7 has been made on the basis of studying the correlation of seismicity with the lunar tide with a 18.6-year period. A possibility has been found for using the phenomenon of “induced foreshocks” for earthquake prediction, i.e., when a large remote earthquake induces small preceding events in the zone of preparation of a large earthquake. The following three methods were used for operative short-term prediction of the time and place of future earthquakes with M > 5.5. 1.(1) Use of specific electrotelluric field anomalies, from 5 to 20 days in duration, which are recorded by a specially designed network of stations. 2.(2) Method of Vp/Vs anomalies. The anomalously high and low Vp/Vs values for a seismic station point to the possibility of large earthquakes near the latter. 3.(3) The earthquake statistics method described by Fedotov et al. in 1972. Short-term seismic prediction is being made twice a week in two versions: Forecast I (for the whole of Kamchatka) and Forecast II (for each of six overlapping segments of the Kamchatka seismic zone). This paper discusses the results of successful testing of short-term earthquake prediction during two years. During the “alarm” periods the probability of large earthquakes is double the average. Paper presented at the Symposium on Earthquake Forerunners Searching, Tashkent, May 26–June 1, 1974

Plasma focus installation as a tool for the study of the interaction of high power plasma streams with condensed matter

In this work the possibilities of the use of the high-current discharges of Plasma Focus type for the investigation of the effect of plasma on the materials are discussed. From this point of view the properties of plasma streams and ion beams arising in the PF discharges are studied. Here, as an example of an application of the Plasma Focus device (PF), we studied the influence on Vanadium (perspective material in nuclear power engineering) a cumulative streams producing in the P