Perspex windows

The Perspex windows of low-temperature cuvettes easily become scratched and Avill eventually crack. However, provided they are still liquid-tight (at least for as long as it takes to pltmge them and their contents into liquid nitrogen) they are quite serviceable in this condition. The opacity of the Perspex is negligible compared with that of the frozen sample. 

All experiments were performed with air at ambient temperature as the fluidizing medium. Its density was adjusted where necessary by operating at elevated pressure. This was achieved in a pressure vessel specially designed to enable visual observation of transparent beds through narrow, vertical, perspex windows. Through these the bed surface comportment was observed and recorded on videocassette. The instantaneous pressure, at a fixed level above the distributor plate, was measured continuously with a piezoelectric sensor, and sampled at a frequency of 20 Hz... 

Perspex, lucite. Transparent sheet and mouldings. Aircraft windows, laminated windscreens. 

A special titration cell is necessary which completely fills the cell compartment of the spectrophotometer. One shown in Fig. 17.24 can be made from 5 mm Perspex sheet, cemented together with special Perspex cement, and with dimensions suitable for the instrument to be used. Since Perspex is opaque to ultraviolet light, two openings are made in the cell to accommodate circular quartz windows 23 mm in diameter and 1.5 mm thick the windows are inserted in such a way that the beam of monochromatic light passes through their centres... 

The first ester, methyl methacrylate is a bulk chemical. It is the monomer whose polymerization (Chapter 52) gives Perspex, the rigid transparent plastic used In windows and roofs. The second ester is an important local anaesthetic used for... 

Poly(methyl methacrylate) Aircraft windows, glazing, fighting Plexiglas, Perspex... 

Methyl methacrylate CH, 1 CH5=C - 1 c=o 1 OCH3 Poly(methyl methacrylate) (PMMA) CH, —f-CH,—C— C=0 1 OCH3, Transparent sheets and moldings more expensive than PS known as organic gloss, used for aeroplane windows e.g.. Perspex, Plexiglass, Lucite, Diakon, Vedril. 

The transparent antistatic coating for meter windows is an old requirement and this coating has been used for many years on both glass and plastic substrates. Figure 42 shows the spectral characteristic of such a film. The surface resistance of approximately 1015 ohms/square of Perspex, is reduced to less than 105 ohms/square by the antistatic film. This resistance is not exceeded through ageing processes. The... 

Figure 6.3 The Mark II cavity spectrometer viewed through its Perspex cover. The spatial filter is visible in the centre of the case. The translation stage and piezoelectric actuator are seen in the foreground and operate via the bellows to move the near mirror. The coupling iris is in the centre of the far mirror. The waveguide couplings holding the mica vacuum windows can be seen either side of the case in the background. Sample inlet is on the left wall of the case not visible and outlet is on the right via the pressure sensor...

Cu+Al filter, the second with a perspex filter, and the third with an open window (D, Dz and D3, respectively). Each of the detectors showed dependence on the X-ray photon energies. The values however were nearly constant over the whole range of... 

Figure 5. Cell for electronic studies, (A) thermo-electric temperature block 5x7.5 cm, (B) silicone rubber gasket with centrally located 0.3 cm diam. window, (C) Perspex compartment 5x7.5x0.45 cm with 0.3 cm diam. window and 0.3 cm channel for introduction of reference electrode bridge-G, (D) silicone rubber gasket with 0.3 cm diam. window, (E) Perspex cover plate, (F) Pt counter-electrode, and (H) membrane plated Pt electrode.

A uniform ab.sorber with randomly oriented crystallites can be prepared easily by sandwiching the finely ground material between the thin windows of a Perspex holder. In order to obtain undistorted line shapes it is desirable that the absorber is thin . The natural line width r a, of the Mossbauer line having Lorentzian shape [see Section 19.2.1, Eq. (3)] is determined, as already discussed, by the half-life of the excited nuclear state and the Heisenberg uncertainty principle. The ex-... 

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