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Mirrors cylindrical

These modes of operation ate used in conjunction with the two most popular energy analyzers, the cylindrical mirror analyzer (CMA) and the concentric hemispherical analyzer (CHA). The most common form of the CMA used today is the double-pass version diagramed in Eigute 21. This device consists of two perfectly coaxial cylinders of radii r and r. The outer cylinder is held at a potential of (— ) and the inner cylinder is held at ground. The... [Pg.283]

It is known that a metallic ID system is unstable against lattice distortion and turns into an insulator. In CNTs instabilities associated two kinds of distortions are possible, in-plane and out-of-plane distortions as shown in Fig. 8. The inplane or Kekuld distortion has the form that the hexagon network has alternating short and long bonds (-u and 2u, respectively) like in the classical benzene molecule [8,9,10]. Due to the distortion the first Brillouin zone reduees to one-third of the original one and both K and K points are folded onto the F point in a new Brillouin zone. For an out-of-plane distortion the sites A and B are displaced up and down ( 2) with respect to the cylindrical surface [11]. Because of a finite curvature of a CNT the mirror symmetry about its surface are broken and thus the energy of sites A and B shift in the opposite direction. [Pg.69]

XPS spectra were obtained using a Perkin-Elmer Physical Electronics (PHI) 555 electron spectrometer equipped with a double pass cylindrical mirror analyzer (CMA) and 04-500 dual anode x-ray source. The x-ray source used a combination magnesium-silicon anode, with collimation by a shotgun-type collimator (1.). AES/SAM spectra and photomicrographs were obtained with a Perkin-Elmer PHI 610 Scanning Auger Microprobe, which uses a single pass CMA with coaxial lanthanum hexaboride (LaBe) electron gun. [Pg.38]

The surface reactions were investigated by a combination of AES and TPR studies, with authentic samples of the expected products being used to calibrate the signals from the two techniques. The Auger spectra were obtained with a single pass cylindrical mirror analyzer operated with a modulation amplitude of 4 eV the surface heating rate in the TPR studies was 2 K/s. [Pg.308]

The energies of the Auger electrons leaving the sample are determined in a manner similar to that employed for photoelectrons already described in chapter 2 Section 4. Modern instruments nearly always incorporate cylindrical mirror analysers (CMA) because their high transmission efficiency leads to better signal-to-noise ratios than the CHA already described. [Pg.172]

Figure 5.30. Schematic diagram of a cylindrical mirror electron energy analyser. Figure 5.30. Schematic diagram of a cylindrical mirror electron energy analyser.
As predicted by elementary hybrid bonding theory, the multiple bonds of the chemist s Lewis-structure diagram are usually found to correspond to two distinct types of NBOs (1) sigma-type, having exact or approximate cylindrical symmetry about the bond axis (as discussed in Sections 3.2.5-3.2.7), and (2) pi-type, having a nodal mirror plane passing through the nuclei 44... [Pg.151]

Cylindrical alkaline primary cells, 3 441-449 anode, 3 443-444 cathode, 3 444-446 cell chemistry, 3 443 performance, 3 446-449 zinc oxidation mechanism, 3 444-446 Cylindrical element filters, 11 362—364 Cylindrical guided wave technique, for pipe inspection, 17 433-434 Cylindrical micelle, 24 124 Cylindrical mirror analyzer (CMA), 24 103-104... [Pg.244]

The above figures are often approximated by the simpler cylindrical or toroidal mirrors, but these are much less efficient and give significantly increased aberrations... [Pg.34]

They used a vertical cylindrical pot furnace of batch type, like Rogers. Two conversion concepts were simulated (a) overfired, updraft, fixed horizontal grate, and batch reactor and (b) underfired, updraft, fixed horizontal grate, and batch reactor. The diameter was 178 mm and primary air was supplied under the grate (Figure 7). A mirror was placed above the overbed section to be able to observe the combustion behaviour. [Pg.61]

A deton wave once formed in an expl has a tendency to die out or "fade if the diam of the expl is below a certain min (called boundary diam). It may be detd by using a cast cone detonated from the base. The diam of the cone at which the wave is extinguished is a measure of the fading properties of the expl. The observation may be made photographically by means of a rotating mirror camera. The value so obtd tends to be less than the value from cylindrical columns of expl. See Vol 4, p D223 Ref D.W. Woodheath R. Wilson, Nature 167, 565(1951)... [Pg.384]

In this chapter we consider theories of scattering by particles that are either inhomogeneous, anisotropic, or nonspherical. No attempt will be made to be comprehensive our choice of examples is guided solely by personal taste. First we consider a special example of inhomogeneity, a layered sphere. Then we briefly discuss anisotropic spheres, including an exactly soluble problem. Isotropic optically active particles, ones with mirror asymmetry, are then considered. Cylindrical particles are not uncommon in nature—spider webs, viruses, various fibers—and we therefore devote considerable space to scattering by a right circular cylinder. [Pg.181]

Experiments were performed using a titanium sapphire laser oscillator capable of producing pulses with bandwidths up to 80 nm FWHM. The output of the oscillator was evaluated to make sure there were no changes in the spectrum across the beam and was compressed with a double prism pair arrangement. The pulse shaper uses prisms as the dispersive elements, two cylindrical concave mirrors, and a spatial light modulator (CRI Inc. SLM-256), composed of two 128-pixel liquid crystal masks in series. The SLM was placed at the Fourier plane [5]. After compression and pulse shaping, 200 pJ pulses were used to interrogate the samples. [Pg.95]


See other pages where Mirrors cylindrical is mentioned: [Pg.694]    [Pg.61]    [Pg.284]    [Pg.192]    [Pg.2406]    [Pg.315]    [Pg.330]    [Pg.447]    [Pg.515]    [Pg.765]    [Pg.35]    [Pg.35]    [Pg.671]    [Pg.233]    [Pg.311]    [Pg.81]    [Pg.99]    [Pg.509]    [Pg.468]    [Pg.752]    [Pg.226]    [Pg.147]    [Pg.64]    [Pg.53]    [Pg.263]    [Pg.133]    [Pg.595]    [Pg.24]    [Pg.418]    [Pg.137]    [Pg.220]    [Pg.128]    [Pg.249]    [Pg.392]    [Pg.124]    [Pg.340]   


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