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After-damp

Stickwetter, n.pl. (Mining) foul air, choke damp, after-damp, nitrous fumes. [Pg.429]

The free carrier optical reflection of test modules before and after damp heat indicates that the effective carrier density is not much affected [58]. Hence, the degradation of the ZnO sheet resistance is probably more of a carrier transport problem. It is, at present, unclear where electron barriers are located. They may be present at the grain boundaries in general [59]. In this case, the disturbances of the ZnO microstructure (induced by the substrate but also depending on preparation parameters) are only harmful because they allow a faster penetration of the humidity into the film. On the other hand, the disturbed regions may themselves be highly resistive after damp heat exposure, which forces the current to percolate around these... [Pg.429]

In mines, after explosions of fire-damp." These ec osions are euaneA by the sudden union ol the C and H of with the O of the air, and are consequentiy attended by the foinnatioii of large volumes of CO known to miners as after-damp,... [Pg.170]

Add-fonning oxidoi, 198 Action, ctaemioal, 46 Adamantine boron. 642 After-damp, 609 A( 58 570... [Pg.756]

New test, after these modification s, showed better measurements up to 350 m/min but now it also became evident that oil from the drawing process build up on the transducer surface and damped the signals and made measurements impossible. The oil build up as a combination of inspection length (m of tubes) and inspection speed. At lower drawing velocities (70 m/min) the oil obvious was washed away giving no inspection problems. The water system was modified as follows ... [Pg.899]

According to Kramers model, for flat barrier tops associated with predominantly small barriers, the transition from the low- to the high-damping regime is expected to occur in low-density fluids. This expectation is home out by an extensively studied model reaction, the photoisomerization of tran.s-stilbene and similar compounds [70, 71] involving a small energy barrier in the first excited singlet state whose decay after photoexcitation is directly related to the rate coefficient of tran.s-c/.s-photoisomerization and can be conveniently measured by ultrafast laser spectroscopic teclmiques. [Pg.820]

In protected motors failure may be due to accumulation of fly ash at the overhangs (modern installations use only enelosed motors). Fly ash beeomes an extremely good conductor when damp. The failure will generally occur when a motor is switched on after a prolonged shutdown. [Pg.241]

The information in Sections 2.2, 2.4 and 3.3 is relevant for protection criteria. Investigations [43] with steel-concrete test bodies have shown that even in unfavorable conditions with aerated large-area cathodes and small-area damp anodes in Cl -rich alkaline environments, or in decalcified (neutral) surroundings with additions of CU at test potentials of (/f.y.cuso4 = -0.75 and -0.85 V, cell formation is suppressed. After the experiments had proceeded for 6 months, the demounted specimens showed no recognizable corrosive attack. [Pg.429]

The principal applications for furan resins are in chemical plant. Specific uses include the lining of tanks and vats and piping and for alkali-resistant tile cements. The property of moisture resistance is used when paper honeycomb structures are treated with furan resins and subsequently retain a good compression strength even after exposure to damp conditions. [Pg.812]

When a damp cloth is laid in an air flow, it settles after a certain time ic an equilibrium temperature, the so-called wet bulb temperature (0 ), which is determined through heat and mass transfer. Negotiating the heat flow obtained by radiation and conduction, the heat balance of the wet cloth in a stationary situation can be expressed as... [Pg.79]

In a hydrogenation autoclave are introduced 92 g of 2-hydroxy-4-nitrophenylbenzoate preceded by 200 cc of ethyl acetate Raney nickel, obtained from 30 g of alloy, is added with 300 cc of ethyl acetate. Hydrogenation under pressure (100 to 120 kg) at ordinary temperature is carried out during a period of about 12 hours. The nickel is filtered off and the ethyl acetate is removed by distillation on the water bath under a vacuum of 300 mm. There is thus obtained 80 g of crude damp 2-hydroxy-4-aminophenylbenzoate which after recrystallization from isopropyl alcohol melts at 153°C. [Pg.1216]


See other pages where After-damp is mentioned: [Pg.236]    [Pg.236]    [Pg.148]    [Pg.116]    [Pg.764]    [Pg.66]    [Pg.49]    [Pg.236]    [Pg.236]    [Pg.148]    [Pg.116]    [Pg.764]    [Pg.66]    [Pg.49]    [Pg.868]    [Pg.862]    [Pg.1211]    [Pg.1349]    [Pg.153]    [Pg.81]    [Pg.604]    [Pg.138]    [Pg.459]    [Pg.31]    [Pg.32]    [Pg.197]    [Pg.436]    [Pg.470]    [Pg.421]    [Pg.140]    [Pg.301]    [Pg.500]    [Pg.21]    [Pg.92]    [Pg.367]    [Pg.398]    [Pg.673]    [Pg.192]    [Pg.193]    [Pg.257]    [Pg.452]    [Pg.526]    [Pg.814]   
See also in sourсe #XX -- [ Pg.231 ]

See also in sourсe #XX -- [ Pg.66 ]

See also in sourсe #XX -- [ Pg.66 ]




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