Download or read book Propagation Des Ultrasons Dans Les Milieux Faiblement Heterogenes written by Lemlikchi Safia and published by Omniscriptum. This book was released on 2011 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: La th se porte sur une tude th orique et exp rimentale de l'att nuation des ultrasons dans les milieux l g rement h t rog nes. L' tude th orique est essentiellement consacr e aux mod les th oriques de la diffusion des ultrasons dans des milieux faiblement h t rog nes et au calcul de l'att nuation qui en d coule. Une relation th orique entre l'att nuation et la fr quence est tablit. L'att nuation dans les polycristaux est due principalement la diffusion des ondes caus e par les variations des propri t s locales du milieu. Pour mettre ce ph nom ne en vidence, diff rentes th ories ont t d velopp es telles que la th orie des perturbations, la diffusion simple, approximation de Born. Les r sultats des calculs seront toutefois limit s la r gion de Rayleigh. L' tude exp rimentale, porte sur la mesure de l'att nuation dans des chantillons d'acier. Plusieurs m thodes ont t utilis es pour la mesure des vitesses de propagation et de l'att nuation. Les r sultats obtenus ont permis de mettre en vidence la d pendance de l'att nuation en fonction de la fr quence.

Download or read book Properties of UO2 written by J. Belle and published by . This book was released on 1957 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radar Cross Section written by Eugene F. Knott and published by SciTech Publishing. This book was released on 2004-06-30 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt: The leading text and reference on radar cross section (RCS) theory and applications, this work presents a comparison of two radar signal strengths. One is the strength of the radar bean sweeping over a target, the other is the strength of the reflected echo senses by the receiver. This book shows how the RCS "gauge" can be predicted for theoretical objects.

Download or read book U S Research Reactors written by Battelle Memorial Institute. Columbus Laboratories and published by . This book was released on 1957 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Guide To Soil Mechanics written by Malcolm D Bolton and published by Universities Press. This book was released on 2013 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covers all the soil mechanics and foundation engineering topics that are commonly included in civil engineering degree courses, and provides a number of springboards into related advanced topics. Although it is intended principally to satisfy the needs of student civil engineers, this guide should also prove useful to those practicing engineers who are unaware of the powerful and elegant reconstruction of the subject which has been made possible by the recent concepts of plasticity, dilatancy and critical states.

Download or read book Enhanced Abutment Scour Studies for Compound Channels written by Terry W. Sturm and published by DIANE Publishing. This book was released on 2004 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental results and analyses are given in this report on bridge abutment scour in compound channels. Experiments were conducted in a laboratory flume with a cross section consisting of a wide floodplain adjacent to a main channel. The embankment length, discharge, sediment size, and abutment shape were varied, and the resulting equilibrium scour depths were measured. Water-surface profiles, velocities, and scour-hole contours were also measured. In the report, a methodology is developed for estimating abutment scour that takes into account the redistribution of discharge in the bridge contraction, abutment shape, sediment size, and tailwater depth. The independant variables in the proposed scour formula are evaluated at the approach-channel cross section and can be obtained froma one-dimensional water-surface profile computer program such as the Water-Surface Profile Program (WSPRO). The proposed scour evaluation procedure is outlined and illustrated, including consideration of the time required to reach equilibrium scour. The proposed methodology is applied to two cases of measured scour in the field.

Download or read book Matrix Isolation Spectroscopy written by A. Barnes and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 602 pages. Available in PDF, EPUB and Kindle. Book excerpt: The matrix isolation (MI) method has now been used for nearly thirty years. During this period it has been actively developed and the range of problems tackled greatly extended. Originally it was used for studies of transient species involv ing vibrational, electronic and ESR spectroscopy. Nowadays the study of transient species forms a comparatively small part of HI work since it has been amply demonstrated that very fruitful information can be obtained of the structure and interactions of stable molecules and their aggregates. In addition to the s~ectroscopic methods mentioned above the MI technique is nowadays a standard method in research based on vibrational relaxation, luminescence, Mossbauer, magnetic circular dichroism, pulsed NMR and photoelectron spectroscopy. The matrix isolation technique affords considerable advantages over more conventional methods in most applications of spectroscopy. Areas where the technique has been widely applied, or shows great potential, include: metal atom chemistry, and its relation to surface chemistry, high temperature inorganic species, transition metal complexes, interstellar species, free radicals and unstable molecules, conformational studies, molecular com plexes, and intermolecular forces.