The frequency used for these experiments is 15 mc. and the transducer is a specially cut crystal with an epoxy lens capable of providing beam diameters smaller than one millimeter.

Af appeared to be well suited for the study of these matters, since it is a normal paramagnet, with three unpaired electrons on the chromium, its crystal structure is very simple, and the unknown position of the hydrogen in the strong Af bond provides structural interest.

-- The crystallization of copolymers comprising Af units interspersed with a minor percentage of Af is limited by the inability of the crystal lattice characteristic of the former to accommodate the bulky side group of the latter.

The present edition of crystal data ( Af ), published in 1954 as Memoir 60 of the Geological Society of America, is now out of print.

Amethyst is a purple variety of quartz ( SiO < sub > 2 </ sub >) and owes its violet color to irradiation, iron impurities ( in some cases in conjunction with transition element impurities ), and the presence of trace elements, which result in complex crystal lattice substitutions.

Of very variable intensity, the color of amethyst is often laid out in stripes parallel to the final faces of the crystal.

There is one test based on " Brazil law twinning " ( a form of quartz twinning where right and left hand quartz structures are combined in a single crystal ) which can be used to identify synthetic amethyst rather easily.

The implication is that the entropy of a perfect crystal simply approaches a constant value.

A perfect crystal is one in which the internal lattice structure extends uninterrupted in all directions.

The jewel is about long, made of filigreed gold, enclosing a highly polished piece of quartz crystal beneath which is set a cloisonné enamel plaque, with an enamelled image of a man holding floriate sceptres, perhaps personifying Sight or the Wisdom of God.

While the speed of communication is important, so is the fact that the messages cannot be overheard except by listeners with a piece of the original crystal.

Unlike McCaffrey's black crystal transceivers, Le Guin's ansibles are not mated pairs: it is possible for an ansible's coordinates to be set to any known location of a receiving ansible.

The most common type is a piezoelectric pickup, which is composed of a thin sandwich of quartz crystal.

As of 2012, no crystal structure is available for class I AC.

In condensed matter physics, an amorphous ( from the Greek a, without, morphé, shape, form ) or non-crystalline solid is a solid that lacks the long-range order characteristic of a crystal.

Beryllium is a steel gray and hard metal that is brittle at room temperature and has a close-packed hexagonal crystal structure.

The crystal has a double-hexagonal close packing structure with the layer sequence ABAC and so is isotypic ( having a similar structure ) with α-lanthanum and α-forms of actinides beyond curium.

In many superconductors, the attractive interaction between electrons ( necessary for pairing ) is brought about indirectly by the interaction between the electrons and the vibrating crystal lattice ( the phonons ).

In most materials ( in low temperature superconductors ), this attraction is brought about indirectly by the coupling of electrons to the crystal lattice ( as explained above ).

When an electric field is applied to the LC layer, the long molecular axes tend to align parallel to the electric field thus gradually untwisting in the center of the liquid crystal layer.

In an X-ray diffraction measurement, a crystal is mounted on a goniometer and gradually rotated while being bombarded with X-rays, producing a diffraction pattern of regularly spaced spots known as reflections.

When they land on a piece of film or other detector, these beams make a diffraction pattern of spots ; the strengths and angles of these beams are recorded as the crystal is gradually rotated.

If the temperature stays constant at its new value, the pyroelectric voltage gradually disappears due to leakage current ( the leakage can be due to electrons moving through the crystal, ions moving through the air, current leaking through a voltmeter attached across the crystal, etc.

If the crystal is gradually changed from one structure to another, there will be a current inside each unit cell, due to the motion of nuclei and electrons.

As the crystal is cooled below the Curie temperature, it shifts gradually into a more and more non-centrosymmetric configuration.

Can fire eye lasers, deliver a shockwave attack or place a crystal that heals him gradually.

Pasteur separated the left and right crystal shapes from each other to form two piles of crystals: in solution one form rotated light to the left, the other to the right, while an Racemic mixture | equal mixture of the two forms canceled each other's effect, and does not rotate the polarized light.

If the applied voltage is large enough, the liquid crystal molecules in the center of the layer are almost completely untwisted and the polarization of the incident light is not rotated as it passes through the liquid crystal layer.

The crystal is mounted for measurements so that it may be held in the X-ray beam and rotated.

To collect all the necessary information, the crystal must be rotated step-by-step through 180 °, with an image recorded at every step ; actually, slightly more than 180 ° is required to cover reciprocal space, due to the curvature of the Ewald sphere.

It occurs in solutions of chiral molecules such as sucrose ( sugar ), solids with rotated crystal planes such as quartz, and spin-polarized gases of atoms or molecules.

For a linear input polarization ( often oriented at 45 ° to the crystal axes ), the output polarization will in general be elliptical, rather than simply a linear polarization state with a rotated direction.

Treating a grain boundary geometrically as an interface of a single crystal cut into two parts, one of which is rotated, we see that there are five variables required to define a grain boundary.

As the light flows out of the rear polarizer, it will naturally follow the liquid crystal's twist, exiting the front of the liquid crystal having been rotated through the correct angle, that allows it to pass through the front polarizer.

AT-cut crystals are singularly rotated Y-axis cuts in which the top and bottom half of the crystal move in opposite directions ( thickness shear vibration ) during oscillation.

Lack's crystal didn't need the heavy accessories previous crystal used, facilitating its use on aircraft.

Mataré had previous experience in developing crystal rectifiers from silicon and germanium in the German radar effort during World War II.

In reality, due to the crystal structure properties, the hole is not localized to a single position as described in the previous example.

When he went for interview for entrance to the Royal Naval College, Osborne, Isle of Wight, Charles Rolls had completed his cross-channel flight the previous day and Blackett who had tracked the flight on his crystal set was able to expound lengthily on the subject.

Balmat, a chamois hunter and crystal collector, had experience with high mountain travel, and Paccard had made previous attempts to climb the peak.

A lattice in the sense of a 3-dimensional array of regularly spaced points coinciding with e. g. the atom or molecule positions in a crystal, or more generally, the orbit of a group action under translational symmetry, is a translate of the translation lattice: a coset, which need not contain the origin, and therefore need not be a lattice in the previous sense.

With the both of them disguised in order to infiltrate the compound, Anakin is able to replace the destroyed crystal of his lightsaber ( the lightsaber's crystal was damaged in a previous confrontation with the Yuuzhan Vong ) with one of the Vong's own lambents ( light-creatures ).

An example of a low-maintenance experiment was the protein crystal growth experiment, which had also been flown on previous shuttle missions.

Similarly to the previous setup, two parallel beams with a variable delay are generated, then focused into a second-harmonic-generation crystal ( see nonlinear optics ) to obtain a signal proportional to.

As a combination of both previous cases, a nonlinear crystal can be used to generate the second harmonic at the output of a Michelson interferometer, in a colinear geometry.

At the end of the Darkwar Saga, Leso Varen is finally killed by Nakor, who removes a black crystal from his heart called " The Godkiller ", and uses that crystal to destroy the Dread Lord who was using the Dasati to invade the realm of Midkemia in an attempt to enter that realm and absorb all life from it, as it had done in previous realms-as shown to Pug by Ban-Ath, the Midkemian god of trickery.