229 research outputs found
Repulsive forces of highly coercive permanent magnets in magnetic clutches and plane magnetic systems
A formula is derived for calculating the repulsive force of highly coercive permanent magnets made from rare-earth metal alloys in frontal magnetic clutches and plane magnetic systems, when the magnets take the form of rectangular prisms. © 2013 Allerton Press, Inc
Centrifugal Extractor with Magnetic Clutch for Chemical Productions
Two alternative designs of a hermetically sealed extractor, the drive of which utilizes a cylindrical magnetic clutch, are examined. In the first version, the driving half coupling is internal, and the driven half coupling external. In the second version, the driving half coupling is external, and the driven internal. It is shown that as the extractor based on the first design begins to accelerate with use of a frequency regulator that permits smooth variation in current frequency, the maximum angle of mismatch between the half couplings of the magnetic clutch is less then 0.5π rad. The proposed design of the extractor has been tested at an establishment manufacturing radiochemical products, and placed in experimental-industrial service. © 2013 Springer Science+Business Media New York
Surface acoustic waves
The book describes surface acoustic waves in solids, one of the most interesting and important types of wave motion. Classification of the main currently known types of surface acoustic waves is given. Their physical properties, including the specifics of propagation, scattering, and interaction with electrons, are discussed. Much of attention is paid to surface waves in piezoelectric crystals, which play a particularly important role with regard to a variety of applications in signal processing devices. There are numerous examples illustrating various manifestations of surface acoustic waves in science and engineering
Introduction to physical acoustics
The book gives a concise account of physical acoustics – a branch of physics studying the interaction of acoustic waves with matter at the macro and microscopic levels. It starts with the basics of mechanics of continuum needed to analyse the problems of physical acoustics. This is followed by the description of linear and nonlinear problems of acoustics of gases, liquids and solids. Also considered are the problems of ‘turbulence and sound’, acoustics of magnetic media, and acoustics of crystals. Important information is provided also on acousto-electronics and acousto-optics. Some parts of the book are illustrated by description of the methodology of experiments and experimental data. The book would be of interest to undergraduate students of physical, chemical and engineering specialities, postgraduate students, researchers, lecturers, acoustic engineers, and all those engaged in fluid mechanics, elasticity, solid state physics, radio physics, signal processing, underwater acoustics and geophysics. (Abstract translated from the Russian)
Abstract wave equations with acoustic boundary conditions
We define an abstract setting to treat wave equations equipped with
time-dependent acoustic boundary conditions on bounded domains of .
We prove a well-posedness result and develop a spectral theory which also
allows to prove a conjecture proposed in (Gal-Goldstein-Goldstein, J. Evol.
Equations 3 (2004), 623-636). Concrete problems are also discussed.Comment: 21 pages. A few minor bugs appearing in the journal version have been
fixe
Kinetics of dislocation ensembles in deformable irradiated materials
The development of plastic instability in the initial deformation stages of irradiated materials is studied. The dependence of the fraction of dislocations which overcome obstacles in the dynamic regime (dislocation ‘‘channeling’’) on the degree of radiation hardening (irradiation dose) and the dislocation velocity is analyzed. It is shown that this effect plays a role in radiation embrittlement of reactor materialsyesBelgorod State Universit
MULTIVALUED SYMPTOMS PSYCHOTHERAPY
This article describes how the rapid development of modern psychotherapy led to a wide variety of areas, and schools, making it difficult to even its single definition. In domestic psychotherapy are two different areas: clinical and psychological therapy, which differ on the project (patients and clients) and their means, which makes their differences with respect to the diagnosis. In psychological therapy services primarily mentally healthy individuals (clients) with personal and situational problems, which are reflected in the symbolic form of symptoms, psychiatric diagnosis and, therefore, is of secondary importance. While clinical psychotherapy busy treating people with mental disorders, for which the identification of symptoms and psychiatric diagnosis is essential. The expediency of psychiatric diagnosis prior to psychological therapy. The expediency of adequate combined use of psychopharmacological and psychological tools in clinical psychotherapy. The analysis of the differences between the concepts of the phenomenon and psychopathological symptoms. Describes the idea of the systemic nature of psychopathological symptoms and justifying the importance of symptomatic therapy
Promicromonospora umidemergens sp. nov., isolated from moisture from indoor wall material
Metabolic and evolutionary insights into the closely-related species Streptomyces coelicolor and Streptomyces lividans deduced from high-resolution comparative genomic hybridization
Whilst being closely related to the model actinomycete Streptomyces coelicolor A3(2), S. lividans 66 differs from it in several significant and phenotypically observable ways, including antibiotic production. Previous comparative gene hybridization studies investigating such differences have used low-density (one probe per gene) PCR-based spotted arrays. Here we use new experimentally optimised 104,000 × 60-mer probe arrays to characterize in detail the genomic differences between wild-type S. lividans 66, a derivative industrial strain, TK24, and S. coelicolor M145
Estrogen regulation of apoptosis: how can one hormone stimulate and inhibit?
The link between estrogen and the development and proliferation of breast cancer is well documented. Estrogen stimulates growth and inhibits apoptosis through estrogen receptor-mediated mechanisms in many cell types. Interestingly, there is strong evidence that estrogen induces apoptosis in breast cancer and other cell types. Forty years ago, before the development of tamoxifen, high-dose estrogen was used to induce tumor regression of hormone-dependent breast cancer in post-menopausal women. While the mechanisms by which estrogen induces apoptosis were not completely known, recent evidence from our laboratory and others demonstrates the involvement of the extrinsic (Fas/FasL) and the intrinsic (mitochondria) pathways in this process. We discuss the different apoptotic signaling pathways involved in E2 (17β-estradiol)-induced apoptosis, including the intrinsic and extrinsic apoptosis pathways, the NF-κB (nuclear factor-kappa-B)-mediated survival pathway as well as the PI3K (phosphoinositide 3-kinase)/Akt signaling pathway. Breast cancer cells can also be sensitized to estrogen-induced apoptosis through suppression of glutathione by BSO (L-buthionine sulfoximine). This finding has implications for the control of breast cancer with low-dose estrogen and other targeted therapeutic drugs
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