462 research outputs found
Diode Based on Amorphous SiC
Diode structure on the basis of amorphous silicon carbide and p-type polycrystalline silicon (Eurosolar) were obtained with magnetron RF-nonreactive sputtering method from solid-phase target in argon atmosphere.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3365
Transition radiation of fast electrons as a broadband vacuum-ultraviolet radiation source
The characteristics of a possible radiation source in the vacuum ultraviolet and soft X ray range based on the transition radiation of electrons with an energy of about 100 keV are calculated. The possibilities of enhancing the radiation yield in the geometry of the glancing interaction of electrons with a target are ana lyzed. The possibility of creating a source with a yield on the order of 10–5 photon/(eV sr) per electron is dem onstratedyesBelgorod State National Research Universit
A COMPARATIVE STUDY OF SPRING TRITICALE VARIETIES IN THE WESTERN SIBERIAN FOREST-STEPPE ZONE UNDER DIFFERENT CONDITIONS OF VEGETATION
Spring triticale (x Triticosecale Wittmack) for Western Siberia is new and poorly studied culture. The objective of this study was to investigate the potential of spring triticale varieties and breeding lines and their adaptation to diferent conditions in Western Siberia. A ield experiment was conducted in Novosibirsk region, Russia in 2014. The experiment included seven spring triticale genotypes: the elite variety Ukro, three mutant forms of the facultative type of development (Sirs 57/2/4, Cecad 90/5, О.312/38) and three hybrids (Sirs 57/2/4 x Ukro, Ukro x K-3881, the complex hybrid winter wheat Filatovka x winter rye Korotko stebelnaya 69304 x Sirs 57/2/4). They were studied at two sowing rates (400 seeds per m2 and 800 seeds per m2) and on two sowing dates (15 May 2014 and 27 May 2014). The following attributes were measured: grain yield, number of ears, plant height, yield components (ear length, number of spikelets per ear, number of grains per ear, grains weight per ear) and yield quality (1 000-grain weight and test weight of one-liter grain volume). The three-factor analysis of variance revealed that sowing rate efect explained the major part of the total experimental variation in almost all of the traits, except 1 000-grain weight and test weight, the variation of which was determined predominantly by genotype efect. The highest grain productivity of varieties was obtained for the 15 May sowing date at the 400 seeds per m2 sowing rate. The three mutant forms used in the experiment showed a lower level of adaptability in comparison with the variety Ukro
A comparison of statistical methods for assessing winter wheat grain yield stability
The multitude of existing methods for assessing the phenotypic stability of plants makes breeders be faced with the problem of choosing an appropriate variant. The purpose of this study was to compare different methods of analyzing the genotype x environment interaction and, on their basis, assess the stability of the yield of 7 varieties of winter wheat. The article compares 17 stability statistics by applying them to data obtained from agrotechnical experiments carried in 2009-2011 for evaluating the grain yield of 7 varieties of winter common wheat of Siberian selection (Novosibirskaya 32, Novosibirskaya 40, Novosibirskaya 51, Novosibirskaya 3, Novosibirskaya 2, Obskaya winter, Omskaya 6). Analysis of variance revealed a significant (p < 0.001) genotype x environment interaction in the experiments, which indicates a different reaction of genotypes to changes in environmental conditions. Genotypes were ranked according to the level of stability. Based on the analysis of the rank correlation matrix, the stability statistics were categorized in five groups. Recommendations were made on which group of methods to use depending on the objectives of the study. In the case when the goal of breeding research is the selection of the most biologically stable varieties with the minimum variance across a range of environments, one should use the methods of the static concept. If it is necessary to choose a genotype with a predictable reaction to changes of environmental conditions, corresponding to the calculated level or forecast, the regression approach is the most appropriate. The stability statistics generally identified Novosibirskaya 32 as the most stable variety from a biological point of view. The regression approach showed that Novosibirskaya 3 was the genotype with the smallest deviation from mean yield in all environments, while methods accessing the contribution of each genotype to the genotype x environment interaction defined Novosibirskaya 51 as the most stable variety
A novel path to runaway electron mitigation via deuterium injection and current-driven MHD instability
Relativistic electron (RE) beams at high current density (low safety factor, q ( a )) yet very low free-electron density accessed with D-2 secondary injection in the DIII-D and JET tokamak are found to exhibit large-scale MHD instabilities that benignly terminate the RE beam. In JET, this technique has enabled termination of MA-level RE currents without measurable first-wall heating. This scenario thus offers an unexpected alternate pathway to achieve RE mitigation without collisional dissipation. Benign termination is explained by two synergistic effects. First, during the MHD-driven RE loss events both experiment and MHD orbit-loss modeling supports a significant increase in the wetted area of the RE loss. Second, as previously identified at JET and DIII-D, the fast kink loss timescale precludes RE beam regeneration and the resulting dangerous conversion of magnetic to RE kinetic energy. During the termination, the RE kinetic energy is lost to the wall, but the current fully transfers to the cold bulk thus enabling benign Ohmic dissipation of the magnetic energy on longer timescales via a conventional current quench. Hydrogenic (D-2) secondary injection is found to be the only injected species that enables access to the benign termination. D-2 injection: (1) facilitates access to low q ( a ) in existing devices (via reduced collisionality & resistivity), (2) minimizes the RE avalanche by 'purging' the high-Z atoms from the RE beam, (3) drives recombination of the background plasma, reducing the density and Alfven time, thus accelerating the MHD growth. This phenomenon is found to be accessible when crossing the low q ( a ) stability boundary with rising current, falling toroidal field, or contracting minor radius-the latter being the expected scenario for vertically unstable RE beams in ITER. While unexpected, this path scales favorably to fusion-grade tokamaks and offers a novel RE mitigation scenario in principle accessible with the day-one disruption mitigation system of ITER
Transition radiation of fast electrons as a broadband vacuum-ultraviolet radiation source
On the mechanisms governing gas penetration into a tokamak plasma during a massive gas injection
A new 1D radial fluid code, IMAGINE, is used to simulate the penetration of gas into a tokamak plasma during a massive gas injection (MGI). The main result is that the gas is in general strongly braked as it reaches the plasma, due to mechanisms related to charge exchange and (to a smaller extent) recombination. As a result, only a fraction of the gas penetrates into the plasma. Also, a shock wave is created in the gas which propagates away from the plasma, braking and compressing the incoming gas. Simulation results are quantitatively consistent, at least in terms of orders of magnitude, with experimental data for a D 2 MGI into a JET Ohmic plasma. Simulations of MGI into the background plasma surrounding a runaway electron beam show that if the background electron density is too high, the gas may not penetrate, suggesting a possible explanation for the recent results of Reux et al in JET (2015 Nucl. Fusion 55 093013)
Modelling of the effect of ELMs on fuel retention at the bulk W divertor of JET
Effect of ELMs on fuel retention at the bulk W target of JET ITER-Like Wall was studied with multi-scale calculations. Plasma input parameters were taken from ELMy H-mode plasma experiment. The energetic intra-ELM fuel particles get implanted and create near-surface defects up to depths of few tens of nm, which act as the main fuel trapping sites during ELMs. Clustering of implantation-induced vacancies were found to take place. The incoming flux of inter-ELM plasma particles increases the different filling levels of trapped fuel in defects. The temperature increase of the W target during the pulse increases the fuel detrapping rate. The inter-ELM fuel particle flux refills the partially emptied trapping sites and fills new sites. This leads to a competing effect on the retention and release rates of the implanted particles. At high temperatures the main retention appeared in larger vacancy clusters due to increased clustering rate
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