Electric discharge, and

Plenary 9. J W Nibler et al, e-mail address niblerj chem.orst.edu (CARS and SRS). High resolution studies of high lymg vibration-rotational transitions in molecules excited in electrical discharges and low density monomers and clusters in free jet expansions. Ionization detected (REMPI) SRS or IDSRS. Detect Raman... 

Small quantities of ozone are produced when oxygen and air are subjected to an electrical discharge and it is, therefore, found in the neighbourhood of working electrical machines. Probably a small quantity of atomic oxygen is initially produced most of this recombines quickly to give oxygen, Oj, but a few atoms react to form ozone ... 

Ozone is normally produced by the use of a silent electrical discharge and a number of ozonisers have been produced. Brodie s apparatus is shown in outline in Figure 10.2. 

The vertical tube (water-cooled) generator consists of two concentric tubes the outer of which is cooled with water and acts as the ground electrode. Feed gas is introduced into the top of the inner stainless steel tube (which serves as the high voltage electrode), exits at the bottom of the outer tube, flows upward through the aimular space (which contains the electric discharge), and emerges at the top of the outer tube into a product gas manifold. 

Ionization The process of adding electrons to, or removing electrons from, atoms or molecules, thereby creating ions. High temperatures, electrical discharges, and nuclear radiation can cause ionization. 

Dust particles may be removed from air by passing the air through an electrical discharge and then between a pair of oppositely charged metal plates. Explain how this removes the dust. 

Stanley Miller at the University of Chicago more than 50 years ago. This experiment (in fact, of course, many were carried out prior to the successful one) is probably as well known as the Wohler synthesis of urea Miller s doctoral supervisor, Harold Urey (winner of the Nobel Prize in 1934), had suggested to Miller that he simulate a reducing primeval Earth atmosphere (as required by the Oparin-Haldane hypothesis) to electrical discharges and see what happens . Urey apparently expected that such an experiment would lead to a huge variety of organic compounds. 

Electrical discharges and other forms of highly energetic radiation caused these simple compounds to fragment into highly reactive pieces which combine into more complex compounds such as amino acids, formaldehyde, hydrogen cyanide, purines, and pyrimidines. 

Instability of electrical discharges and matrix effects lead to only moderate precision. 

Static electricity discharges and unexpected electrical currents are frequently overlooked as potential sources of ignition that must be controlled. Some of the conditions that may result in sufficiently intense electrical discharges or arcing are ... 

Ozonolysis. Ozone was generated from oxygen by silent electric discharge, and bubbled through the reaction mixtures from a capillary tip. The ozone concentration was monitored spectrophotometrically at 350 nm by the KI method as previously described (8). 

In the 1960 s, interest turned to the oxidation of perfluorocarbons. In the United States, much work has been done at the Aerospace Corporation Photochemical, thermal, electric-discharge, and flame studies, as well as oxidation initiated by oxygen atoms and ozone, were performed in El Segundo, California. High-temperature studies were performed at the... 

The first two methods of ozone production, electrical discharge and electrolysis, are the only ones of practical importance both in bench- and full-scale applications and are further discussed in the following section. 

Table 2-3 Characteristic operating parameters of electrical discharge and electrolytic ozone generators.

Harteck179 was the first to report that RNO could polymerize. He passed hydrogen through an electric discharge and then into NO, and was able to trap a yellow solid of empirical formula (HNO)n at liquid air temperature. This solid decomposed on warming. 

Electric discharges and ultraviolet light give no organic compounds with a mixture of C02 + H20. Ionizing radition (e.g., 40 MeV helium ions) gives small yields of formic acid and formaldehyde.25... 

There would appear to be no difference in the reactions expected photo-chemically as the primary products are H atoms and OH radicals in both the electric discharge and on irradiation. Chen and Taylor (22) state that there is no evidence for oxygen atoms either in the photolysis or in the decomposition of water vapor in an electric discharge. However, the secondary formation of O atoms (2) and the formation of ozone (31, 50) in an electric discharge through water vapor have been demonstrated. It might be expected that under the proper experimental conditions similar results could be obtained photochemically. 

Mercuric nitride of undetermined composition was stated by R. Threlfall to be formed as a brown film by tbe action of nitrogen on mercury wben the gas under diminished press, is under the influence of an electric discharge and-R. J. Strutt found that activated nitrogen reacts with mercury, forming a nitride. F. Fischer and F. Schroter also prepared the nitride by the process indicated in connection with Fig. 11. O. Flasehner found that scarcely any hydroxylamine is reduced by the mercury cathode. 

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