1,541 research outputs found
Doping effect on the evolution of the pairing symmetry in n-type superconductor near antiferromagnetic phase boundary
We present the investigation results of the in-plane \{rho}(T) resistivity
tensor at the temperature range 0.4-40 K in magnetic fields up to 90kOe (H||c,
J||ab) for electron-doped Nd{2-x}Ce{x}CuO{4+{\delta}} with different degree of
disorder near antiferromagnetic - superconducting phase boundary. We have
experimentally found that for optimally doped compound both the upper critical
field slope and the critical temperature decrease with increasing of the
disorder parameter (d-wave pairing) while in the case of the underdoped system
the critical temperature remains constant and (dHc2/dT)|Tc increases with
increasing of the disorder (s-wave pairing). These features suggest a possible
implementation of the complex mixture state as the (s+id)-pairing.Comment: 9 pages, 2 figure
Pathogenetic features of acute naphazoline poisoning in children
Acute poisoning by nasal decongestants is an important issue in pediatrics due to physiological and anatomical characteristics of the child’s body and pharmacokinetics of drugs in early childhoo
Summary of the Surface Processing Process Plastic Deformation
The paper shows that the surface plastic deformation of a deep hole refers to the process of its final processing. Due to this, the roughnesses of the surface layer are smoothed out and a low roughness is achieved, the hole size and roughness change (size finishing), or the necessary stress state and hardening of the metal of the surface layer are created (hardening treatment). This method processes deep holes in parts made of cast iron, steels, including hardened.В работе показано, что поверхностное пластическое деформирование (ППД) глубокого отверстия относится к процессу окончательной его обработки. За счет этого сглаживаются неровности поверхностного слоя и достигается низкая шероховатость (Ra = 0,32–0,08 мкм), происходит изменение размера отверстия и шероховатости (размерно-чистовая обработка) или создается необходимое напряженное состояние и упрочнение металла поверхностного слоя (упрочняющая обработка). Этим методом обрабатываются глубокие отверстия в деталях из чугунов, сталей, в том числе закаленны
Structure and Mechanical Characteristics of Coatings Depending on the Content of Antimony in the Electrolyte
В работе был проведен анализ сплавов Pb–Sn–Sb с различным содержанием сурьмы, используемых для нанесения гальванических покрытий. Результаты анализа будут использованы для разработки новых технологий нанесения антифрикционных покрытий на детали, работающие в условиях трения.The analysis of Pb-Sn-Sb alloys with diff erent antimony content used for electroplating was carried out. The results of the analysis will be used to develop new technologies for applying antifriction coatings to parts operating under friction conditions
Resistivity tensor correlations in the mixed state of electron-doped superconductor Nd2-xCexCuO4+δ
The magnetic-field dependencies of the longitudinal and Hall resistance of the electron-doped compounds Nd2-xCexCuO4+δ in underdoped region with x = 0.14 and with varying degrees of disorder (δ) were investigated. It was established experimentally that the correlation between the longitudinal electrical resistivity and the Hall resistivity can be analyzed on the basis of scaling relationships: ρxy(B) ∼ [ρxx(B)]β. For the totality of the investigated single-crystal films of Nd2-xCexCuO4+δ/SrTiO3 the values of β from 0.8 to 1.55 is found. The observed feature in the electron-doped two-dimensional systems can be associated both with a displaying of anisotropic s - wave or d - wave pairing symmetry and with a pinning due to an essential degree of disorder in the samples under study. © 2016 Published by Elsevier B.V
THE INFLUENCE OF ALLOYING ELEMENTS ON THE PROPERTIES OF THE MATRIX
В статье исследуются факторы, влияющие на износостойкость металлических связок в АКМ. К числу таких факторов прежде всего следует отнести температуру образования композиций и физико-химические взаимодействия в системе алмаз-металл.In the article the factors influencing to a wear resistance metal bond of diamond composite are investigated. To number of such factors, first of all, it is attribute temperature of formation of compositions and physical and chemical interactions in a system diamond – metal
6-methyluracil derivatives as bifunctional acetylcholinesterase inhibitors for the treatment of Alzheimer's disease
© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Novel 6-methyluracil derivatives with ω-(substituted benzylethylamino)alkyl chains at the nitrogen atoms of the pyrimidine ring were designed and synthesized. The numbers of methylene groups in the alkyl chains were varied along with the electron-withdrawing substituents on the benzyl rings. The compounds are mixed-type reversible inhibitors of cholinesterases, and some of them show remarkable selectivity for human acetylcholinesterase (hAChE), with inhibitory potency in the nanomolar range, more than 10 000-fold higher than that for human butyrylcholinesterase (hBuChE). Molecular modeling studies indicate that these compounds are bifunctional AChE inhibitors, spanning the enzyme active site gorge and binding to its peripheral anionic site (PAS). In vivo experiments show that the 6-methyluracil derivatives are able to penetrate the blood-brain barrier (BBB), inhibiting brain-tissue AChE. The most potent AChE inhibitor, 3 d (1,3-bis[5-(o-nitrobenzylethylamino)pentyl]-6-methyluracil), was found to improve working memory in scopolamine and transgenic APP/PS1 murine models of Alzheimer's disease, and to significantly decrease the number and area of β-amyloid peptide plaques in the brain. Head-AChE relief! In our efforts to identify compounds to treat Alzheimer′s disease, we found that 1,3-bis[ω-(substituted benzylethylamino)alkyl]-6-methyluracils bind to the active site gorge and peripheral anionic site of acetylcholinesterase (AChE). These compounds can cross the blood-brain barrier, and decrease the number and area of β-amyloid plaques in the brain
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