Magnetoresistance of n-GaAs at filamentary current flow

A large number of sharp structures are observed in the 4.2 K magnetoresistance of n-GaAs biased above impurity breakdown in a regime where current flow is filamentary. Most of the structures cannot be attributed to spectral properties of the semiconductor such as impact excitation of shallow donors or the magnetoimpurity effect. Experimental results give evidence that these structures are caused by a redistribution of the filamentary current flow when one filament border is swept across an imperfection in the material

Generation and reduction of nitrogen oxides in firing different kinds of fuel in a circulating fluidized bed

The processes through which nitrogen oxides are generated and reduced in the course of firing different kinds of fuel in a circulating fluidized bed are addressed. All experimental studies were carried by the authors on their own laboratory installations. To construct a model simulating the generation of nitrogen oxides, the fuel combustion process in a fluidized bed was subdivided into two stages: combustion of volatiles and combustion of coke residue. The processes through which nitrogen oxides are generated and reduced under the conditions of firing fuel with shortage of oxygen (which is one of efficient methods for reducing nitrogen oxide emissions in firing fuel in a fluidized bed) are considered. © 2013 Pleiades Publishing, Inc

Domain wall effects in ferromagnet-superconductor structures

We investigate how domain structure of the ferromagnet in superconductor-ferromagnet heterostructures may change their transport properties. We calculate the distribution of current in the superconductor induced by magnetic field of Bloch domain walls, find the ``lower critical'' magnetization of the ferromagnet that provides vortices in the superconductor

Critical temperature of superconductor/ferromagnet bilayers

Superconductor/ferromagnet bilayers are known to exhibit nontrivial dependence of the critical temperature T_c on the thickness d_f of the ferromagnetic layer. We develop a general method for investigation of T_c as a function of the bilayer's parameters. It is shown that interference of quasiparticles makes T_c(d_f) a nonmonotonic function. The results are in good agreement with experiment. Our method also applies to multilayered structures.Comment: 4 pages, 2 EPS figures; the style file jetpl.cls is included. Version 2: typos correcte

Experimental Simulation of the Radionuclide Behaviour in the Process of Creating Additional Safety Barriers in Solid Radioactive Waste Repositories Containing Irradiated Graphite

Results of the experimental modeling of radionuclide behavior when creating additional safety barriers in solid radioactive waste repositories are presented. The experiments were run on the repository mockup containing solid radioactive waste fragments including irradiated graphite. The repository mockup layout is given; the processes with radionuclides that occur during the barrier creation with a clayey solution and during the following barrier operation are investigated. The results obtained confirm high anti-migration and anti-filtration properties of clay used for the barrier creation even under the long-term excessive water saturation of rocks confining the repository

On the Long-Range Exciton Transport in Molecular Systems: The Application to H-Aggregated Heterotriangulene Chains

© 2017 American Chemical Society. Self-assembled aggregates of pigment molecules are potential building blocks for excitonic circuits that find their application in energy conversion and optical signal processing. Recent experimental studies of one-dimensional heterotriangulene supramolecular aggregates suggested that singlet excitons in these structures can propagate on several micron distances. We explore this possibility theoretically by combining electronic structure calculations with microscopic models for exciton transport. A detailed characterization of the structural disorder and exciton decoherence is provided. We argue that advanced, well-established exciton transport models, used in our study, give about one order of magnitude shorter estimates for the exciton propagation length which suggest that there are other possible explanations of the experimental results

DYNAMIC OF A STEAM BOILER FURNACE AS A CONTROL SYSTEM PLANT

В работе рассмотрена динамика топки как объекта регулирования тепловыделения, поддержание оптимального коэффициента избытка воздуха и разрежения. Получены уравнения динамики этих величин в приращениях, передаточные функции и составлены структурные схемы, объединение которых позволяет получить структурную схему топки как объекта регулирования процесса горения топлива.Boiler furnace dynamic as a plant of control system was observed. Dynamic incremental equations of main values were produced as well as process transfer function. Graphic patterns of boiler furnace in order to combustion process control were constructed

Layered ferromagnet-superconductor structures: the π\pi state and proximity effects

We investigate clean mutilayered structures of the SFS and SFSFS type, (where the S layer is intrinsically superconducting and the F layer is ferromagnetic) through numerical solution of the self-consistent Bogoliubov-de Gennes equations for these systems. We obtain results for the pair amplitude, the local density of states, and the local magnetic moment. We find that as a function of the thickness $d_F$ of the magnetic layers separating adjacent superconductors, the ground state energy varies periodically between two stable states. The first state is an ordinary "0-state", in which the order parameter has a phase difference of zero between consecutive S layers, and the second is a "$\pi$-state", where the sign alternates, corresponding to a phase difference of $\pi$ between adjacent S layers. This behavior can be understood from simple arguments. The density of states and the local magnetic moment reflect also this periodicity.Comment: 12 pages, 10 Figure

МОРФОЛОГИЧЕСКИЕ ИЗМЕНЕНИЯ МОЛОЧНОЙ ЖЕЛЕЗЫ И ЯИЧНИКОВ У МЫШЕЙ С ЭКСПЕРИМЕНТАЛЬНО ИЗМЕНЕННЫМ ТИРЕОИДНЫМ СТАТУСОМ

The frequency of breast tumors has been studied in inbreed C3H-A mice with affected thyroid status. It has been shown that frequency of breast tumors was significantly higher in the animals with hyperthyroid condition versus the hypothyroid group (рИсследовали частоту возникновения рака молочной железы у инбредных мышей линии С3Н-А с измененным тиреоидным статусом. Выявлено, что частота возникновения рака молочной железы была достоверно выше у животных с длительно протекающим гипертиреозом по сравнению с гипотиреоидной группой (

Predation Stress Causes Excessive Aggression in Female Mice with Partial Genetic Inactivation of Tryptophan Hydroxylase-2: Evidence for Altered Myelination-Related Processes

The interaction between brain serotonin (5-HT) deficiency and environmental adversity may predispose females to excessive aggression. Specifically, complete inactivation of the gene encoding tryptophan hydroxylase-2 (Tph2) results in the absence of neuronal 5-HT synthesis and excessive aggressiveness in both male and female null mutant (Tph2−/−) mice. In heterozygous male mice (Tph2+/−), there is a moderate reduction in brain 5-HT levels, and when they are exposed to stress, they exhibit increased aggression. Here, we exposed female Tph2+/− mice to a five-day rat predation stress paradigm and assessed their emotionality and social interaction/aggression-like behaviors. Tph2+/− females exhibited excessive aggression and increased dominant behavior. Stressed mutants displayed altered gene expression of the 5-HT receptors Htr1a and Htr2a, glycogen synthase kinase-3 β (GSK-3β), and c-fos as well as myelination-related transcripts in the prefrontal cortex: myelin basic protein (Mbp), proteolipid protein 1 (Plp1), myelin-associated glycoprotein (Mag), and myelin oligodendrocyte glycoprotein (Mog). The expression of the plasticity markers synaptophysin (Syp) and cAMP response element binding protein (Creb), but not AMPA receptor subunit A2 (GluA2), were affected by genotype. Moreover, in a separate experiment, naïve female Tph2+/− mice showed signs of enhanced stress resilience in the modified swim test with repeated swimming sessions. Taken together, the combination of a moderate reduction in brain 5-HT with environmental challenges results in behavioral changes in female mice that resemble the aggression-related behavior and resilience seen in stressed male mutants; additionally, the combination is comparable to the phenotype of null mutants lacking neuronal 5-HT. Changes in myelination-associated processes are suspected to underpin the molecular mechanisms leading to aggressive behavior. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Seventh Framework Programme, FP7: 602805; Deutsche Forschungsgemeinschaft, DFG: CRC TRR58A1/A5; Russian Academy of Sciences, РАН: N0520-2019-0031; Horizon 2020: 101007642, 728018Funding: The authors’ animal work reported here was supported by Deutsche Forschungsgemein-schaft (DFG:CRC TRR58A1/A5), the European Union’s Seventh Framework Programme (FP7/2007– 2013) under Grant No. 602805 (Aggressotype), the Horizon 2020 Research and Innovation Programme under Grant No. 728018 (Eat2beNice) (to K.P.L. and T.S.) and Grant No. 101007642 (PhytoAPP) (to D.A. and T.S.), and Swiss-Russian Cooperation grant RPG Russia 2020 (to S.W. and K.P.L.). Molecular data analysis was supported by RAS N0520-2019-0031 (to E.S. and T.S.). The sponsors had no role in study design, in the collection, analysis, and interpretation of data; in the writing of the report, and in the decision to submit the article for publication