Sample cylindrical wire

We now use the result obtained from the spherical sample in the same way as that for the cylindrical wire. We know that Gd coefficient for diffusion through a spherical layer is (see Table 7.1) given as ... 

HREELS experiments [66] were performed in a UHV chamber. The chamber was pre-evacuated by polyphenylether-oil diffusion pump the base pressure reached 2 x 10 Torr. The HREELS spectrometer consisted of a double-pass electrostatic cylindrical-deflector-type monochromator and the same type of analyzer. The energy resolution of the spectrometer is 4-6 meV (32-48 cm ). A sample was transferred from the ICP growth chamber to the HREELS chamber in the atmosphere. It was clipped by a small tantalum plate, which was suspended by tantalum wires. The sample was radia-tively heated in vacuum by a tungsten filament placed at the rear. The sample temperature was measured by an infrared (A = 2.0 yum) optical pyrometer. All HREELS measurements were taken at room temperature. The electron incident and detection angles were each 72° to the surface normal. The primary electron energy was 15 eV. 

Comparison among the electrical power Ph delivered to the warmer end of the sample, the power Pm shunted by the eight manganin wires and the power PR radiated by the sample toward the cylindrical shield... 

For the CDA experiments described below a PERKIN-ELMER TGS-1 system was used with a cylindrical furnace on alumina ceramic, 6 mm i.d., with bifilar Pt windings as sketched in Fig. lb. The sample, 4x4 mm and 1.5-3 mm thick, was suspended from a fused silica hang-down wire and rested on a fused silica loop below the rim of the furnace. A Ni electrode 3 x 5 mm was introduced sidewise above the furnace, parallel to the sample surface at a distance of <0.5 mm. The temperature (T) was calibrated by means of the Curie points of ferromagnetic alloys. During the runs the balance was... 

The EPR/ENDOR measurements described here have been performed on single crystals which are accurately oriented with an x-ray precession camera, x-ray irradiated, and observed at ca. 10 K. The schematic diagram of the X-band EPR apparatus is shown in Figure 18-1 [12], This cavity is a modification of one previously described by Weil et al. [13], The EPR cavity is essentially a cast epoxy, wire wound TE011 cylindrical cavity with external 100 kHz modulation coils. The Cryo-Tip portion of the cavity can be raised 6 cm for x-irradiation and subsequently lowered into the microwave cavity for EPR measurements [14], In the microwave cavity the lowest temperature of the sample is approximately 6 K. However in the irradiation position the lowest temperature is about 10 K because the sample is not as effectively heat-shielded from the room temperature vacuum shroud. 

The constant S can be calculated in a measurement carried out without the test sample. In fact, in many measurements the equipment is prepared in such a way that S = 0 that is, the purely elastic rigidity of the suspension thread, E, is negligible. Since the flexibility of suspension wires of cylindrical cross section depends on the fourth power of the diameter, this requirement is achieved by using a wire of very small diameter. In these conditions... 

Figure 45(c) shows in principle the adhesive method for the determination of tensile strength. 3 Cylindrical agglomerates with two parallel, flat ends are centrically cemented between two so-called adapters. To eliminate bending stresses it is necessary to machine spherical or nonsymmetrical agglomerates into cylindrical specimens using a special method (Figure 47). This sample is fastened to thin wires and subjected to tensile forces in a conventional testing machine (Figure 48). The tensile strength of the agglomerate is defined as the tensile force P at failure divided by the cross section of the cylindrical specimen.

Fig. 6.5 Some typical sample cells, (a) Various types of optical cell, (b) A completely sealed optical cell, (c) An exploded view of a high-pressure conductivity cell (A) the plug of the high-pressure cell, (B) a hollow cylindrical Kel-F screw, (C) a Teflon cone, (D) a platinum wire lead, (E) a platinum electrode, (F) a Kel-F body, (G) a Viton O-ring, (H) a flexible Teflon tube, (I) a Teflon screw, (J) an aluminium holder, and (K) a steel cone, (d) An inverted pillbox cell for infrared spectroscopy.

Fig. 7.18 A cell used to measure resistivity under high-pressure conditions (A) cylindrical sample, (B) AIF3 layer, (C) microfurnace, (D) porous alumina tube, (E) copper wires (voltage), (F) LajOs layer for protecting the sample from water, (G) call body made from pyrophyllite, (H) thermocouple, and (I) conducting wires for current measurements. ...

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