Intermittent radiation

It might be useful at this point to consider a very important photochemical technique, that involving intermittent radiation. This may be used to determine the average life-times of active intermediates in reactions, e.g. radical polymerisation, and rate coefficients for elementary processes, e.g. radical abstraction reac-... 

Although rocking of the furnace to intermittently cover and hence protect up to 90% of the refractory, as well as improved refractories, has done much to make the indirect-arc furnace more viable, these furnaces are becoming less common, primarily due to high operating costs as a result of erosion of the refractory by the intense arc radiation. 

When radiating and receiving surfaces are not in parallel, as in rotary-ldln devices, and the sohds burden bed may be only intermittently exposed and/or agitated, the calculation and procedures become veiy complex, with photometric methods of optics requiring consideration. The following equation for heat transfer, which allows for convective effects, is commonly used by designers of high-temperature furnaces ... 

Less common causes of peptic ulceration include Zollinger-Ellison syndrome (ZES), cancer chemotherapy, radiation, and vascular insufficiency. ZES is caused by a gastrin-producing tumor called a gastrinoma and results in gastric acid hypersecretion. High-dose oral proton pump inhibitor (PPI) therapy is the initial treatment of choice for ZES intermittent intravenous PPI therapy may be required for any patient in whom oral therapy is contraindicated.1... 

The data obtained here for intermittent stress application (Figure 8) on a polystyrene sample and the data of Mokulskii et al. (Figure 9) for creep of a PVC sample after various times of exposure to the nuclear radiation field can now be interpreted in terms of continued gas buildup within the samples during radiation exposure. This leads to the higher initial creep rates when stress is applied after the radiation beam has... 

The next development was the use of internal cooling by intermittent water circulation during the regeneration period. The heat was removed by radiation and flue gas convection from the walls of perforated pipes to water-cooled tubular coils installed inside these pipes. Thus, direct contact with the catalyst was avoided, which precluded cooling parts of the catalyst to temperatures at which combustion would stop. Most of the heat of combustion was recovered as steam. This was the basis of the design of the first commercial unit installed and operated in 1936. 

Metronidazole, a synthetic nitroimidazole derivative with antibacterial and antiprotozoal activity, is available for oral and parenteral use. Commercially available ready-to-use infusion solutions of metronidazole (100 mL, 5mg/mL) are administered by intermittent IV infusion over a 20- to 30-minute period. The degradation of metronidazole depends on temperature, pH, and radiation conditions. 

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