... materials with different densities (bonehigh, tissue-low density)
• used in medical facilities to get a picture
the human structure, including a fetus that
• can even be concentrated to destroy bad
... 1 b) The geometric arrangement in SiCl4 consist of Si atom in a center of a
tetrahedron and Cl atoms occupying the four corners of the tetrahedron.
1 c) Since the bonding geometry described in 1b) is symmetric it implies that the
molecule has no permanent dipole moment because the centers of positiv ...
... • An Elastic Medium is defined to be one in
which a disturbance from equilibrium
obeys Hooke’s “Law” so that a local
deformation is proportional to an applied force.
• If the applied force gets too large, Hooke’s “Law”
no longer holds. If that happens the medium is no
longer elastic. This is called ...
... decrease. Ph always has positive value and the negative sign in the compensation (R.H.S.) keeps this
relation valid. A material that has a large bulk modulus could be imagined to consist of very tightly
bound spring and ball materials which will quickly transmit a wave. Ideally, elastic deformation ...
... Nature of waves: vibrations that transfer energy
Sound is longitudinal: the motion of the wave is in the same
direction as the energy transfer
In most mediums, the speed of sound is ~343 m/s
... However, electromagnetic waves lose their effectiveness inside dissipative materials, which hinder their
propagation causing the transformation into other energy forms.
The antenna devised from the Sapienza researchers would allow electromagnetic waves to propagate inside
dissipative media without l ...
... Fig. 2: Frequency and dissipation change during adsorption of streptavidin and the
hGBP1 mutants for the overtones 5 (black and green) and 7 (red and blue).
The used crystal with a constant (C) of 17.7 ng cm-2 was covered with a 100 nm gold layer,
which had a mean-square roughness less than 3 nm. Th ...
... Grigorenko and colleagues would already
have found the way to negative refraction.
Although their achievement stops short of
this, they were able, by matching the impedance (defined as the ratio /) of their patterned gold to that of an adjacent dielectric, to
stop it reflecting. This is in itself ...
... inclusions in an isotropic host material  was used. Due to the symmetry of particles, such materials have isotropic
electromagnetic properties at the frequencies lower than the first lattice resonance. A DNG medium consisting of
dielectric spherical particles with different radii was proposed in ...
... (ii). In Compton scattering, the incident photons have wavelength of 0.5nm. Calculate the wavelength
of scattered radiation, if they are viewed at an angle of 450 to the direction of incidence.
... wavelike lattice vibrations of wavelength long compared to
the interatomic spacing are possible. The detailed atomic
structure is unimportant for these waves and their
propagation is governed by the macroscopic elastic
properties of the crystal.
We discuss sound waves since they must correspond to ...
... of the type of bonding. The first term is the attractive component the second is due to
repulsion. Only when m>n will a minimum (equilibrium) value of E is possible.
Equation 1.1 indicates that attractive forces predominate when atoms are far apart and
repulsive interactions predominate when the ato ...
... will travel.
13. Sound energy travels better through most __solids__.
14. Materials that carry sound waves are called ___conductors_____.
15. Materials that don’t carry sound waves are called ______insulators_______.
16. Through which kind of matter does sound travel the slowest? Gas (air)
17. Throu ...
... determine the size of load step, so that a specific material element will enter the plastic stage from elastic
stage or reach failure strain if it is already in plastic stage. Thus when this adaptive load incremental is
applied, it would occur that only element changes its behavior status, i.e., fro ...
... Actual Metamaterials
Most metamaterials with negative refractive index have been
made for microwaves (below left). Such devices are interesting
for making an airplane invisible to radar (wavelength 3 cm) .
... The study of the dynamics of waves, even in simple linear
media, initiated hundreds of year ago, ever and ever leads to
surprisingly new results and insights. One of such “surprises” was the discovery of band gaps in the propagation of
light in materials with the refraction index periodically
... It is very important in the simulation of the geometry to take into
account the gap between crystals that has to be filled with the
Deformation of the structure < gap between edge of the crystal
and structure itself
It is possible to build CFC structure 100um thick
If structure is 1/10 m ...