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Visar resultat 1 - 5 av 119 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Elastic Neutron Scattering at 96 MeV

   Författare :Joakim Klug; Jan Blomgren; Arjan Plompen; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nuclear physics; neutron; detection; CsI; elastic scattering; differential cross section; optical potential; kerma; Kärnfysik; Nuclear physics; Kärnfysik; Applied Nuclear Physics; Tillämpad kärnfysik;

   Sammanfattning : A facility for studies of elastic neutron scattering in the 50–130 MeV range has been developed. In addition to elastic neutron scattering, it has been used for (n,p) and (n,d) reaction experiments. The performance of the device has been illustrated in measurements of the (n,p) and (n,n) cross sections on 1H and 12C. LÄS MER

3. 2. Neutron Scattering at 96 MeV

   Författare :Angelica Öhrn; Jan Blomgren; Robert Haight; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nuclear physics; neutron; elastic scattering; inelastic scattering; differential cross section; optical model potential; Wick s limit; angular distribution; pre-equilibrium; Kärnfysik; Physics; Fysik;

   Sammanfattning : Data on elastic scattering of 96 MeV neutrons from 56Fe, 89Y and 208Pb in the angular interval 10-70° are presented. The previously published data on 208Pb have been extended, as a new method has been developed to obtain additional information at the most forward angles. LÄS MER

4. 3. Scattering of elastic waves by an anisotropic sphere

   Författare :Ata Jafarzadeh; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Sphere; T matrix; Effective wave number; Distribution of inclusions; Phase velocity.; Anisotropy; Attenuation; Scattering;

   Sammanfattning : Scattering of a plane wave by a single spherical obstacle is the archetype of many scattering problems in physics and geophysics. Spherical objects can provide a good approximation for many real objects, and the analytic formulation for a single sphere can be used to investigate wave propagation in more complicated structures like particle composites or grainy materials, which may have application in non-destructive testing, material characterization, medical ultrasound, etc. LÄS MER

5. 4. Elastic wave scattering from corrugated surfaces in anisotropic media

   Författare :Tatiana Krasnova; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; corrugated surface; perturbation approach; scattering; anisotropy; ultrasonic waves; null field approach; integral equation; Green s function;

   Sammanfattning : .... LÄS MER

7. 5. Elastic Wave Propagation in Anisotropic Media. Application to Ultrasonic NDT

   Författare :A. Jonas Niklasson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; layered media; cylinders; cracks; integral equations; scattering; nondestructive testing; elastic waves; ultrasonics; transducers; anisotropy;

   Sammanfattning : The subject of this thesis is elastic wave propagation in anisotropic materials with application to ultrasonic nondestructive testing (NDT). The first part of the thesis is concerned with modeling of ultrasonic transducers and wave propagation in anisotropic materials in general. First, a scalar 2-D case is considered. LÄS MER