Rotational Intensity Distributions of OH and OD in an Electrodeless Discharge through Water Vapor

1953 ◽  
Vol 89 (5) ◽  
pp. 1053-1059 ◽  
Author(s):  
H. P. Broida ◽  
W. R. Kane
Keyword(s):  
Water Vapor ◽  
Electrodeless Discharge

Studies on hydrogen–oxygen systems in the electrical discharge. III. Surface effects

1970 ◽  
Vol 48 (13) ◽  
pp. 2042-2046 ◽  
Author(s):  
Paul E. Brunet ◽  
Xavier Deglise ◽  
Paul A. Giguère
Keyword(s):  
Hydrogen Peroxide ◽  
Water Vapor ◽  
Power Level ◽  
Surface Effects ◽  
Surface Coatings ◽  
Pure Hydrogen ◽  
Pyrolysis Products ◽  
Electrodeless Discharge ◽  
Oxygen Gas ◽  
Hydrogen Peroxide Vapor

Surface effects in the reactions of dissociated hydrogen–oxygen systems and the products condensed therefrom have been investigated. Water vapor at about 0.1 Torr was streamed at high velocity through an electrodeless discharge confined in tubes of different materials or with various surface coatings. In all cases the products trapped in liquid nitrogen evolved oxygen gas on warming, but the relative amounts varied considerably from one type of surface to another. In some cases there was clear evidence that the walls of discharge tube were attacked by hydrogen atom bombardment. The decomposition, both thermal and electrical, of pure hydrogen peroxide vapor was studied likewise. The pyrolysis products gave off very little oxygen on warming. By contrast the products from electrical decomposition, even at low power level, evolved much oxygen, most of it above the melting point.It is concluded that there is always some decomposition of hydrogen peroxide in the trapped products. However, this does not seem sufficient to account for all the evolved oxygen; at least not in the case of dissociated water vapor.

STUDIES ON HYDROGEN–OXYGEN SYSTEMS IN THE ELECTRIC DISCHARGE: I. THE REACTIONS OF HYDROGEN ATOMS WITH HYDROGEN PEROXIDE

1966 ◽  
Vol 44 (8) ◽  
pp. 869-876 ◽  
Author(s):  
Norisuke H Ata ◽  
Paul A. Glguère
Keyword(s):  
Hydrogen Peroxide ◽  
Water Vapor ◽  
Electric Discharge ◽  
Hydrogen Gas ◽  
Reaction Products ◽  
Hydrogen Atoms ◽  
Eutectic Melting ◽  
Electrodeless Discharge ◽  
Liquid Nitrogen Trap ◽  
Unidentified Species

Hydrogen gas partly dissociated in an electrodeless discharge was mixed downstream with hydrogen peroxide vapor at low pressure (0.1 mm Hg) in a liquid nitrogen trap. The reaction products condensed readily on the wall as a clear, yellowish glass resembling that from dissociated water vapor and other related systems. A manometric study of the warming-up process has revealed four distinct steps. The first two, in which only traces of gas are given off, look like the recombination of trapped free radicals. The major evolution of oxygen upon crystallization of the glassy deposit at 160 °K is ascribed to the decomposition of hydrogen peroxide under the influence of some unidentified species generated in the electric discharge through hydrogen. Experimental evidence for this is presented. In any case the stoichiometry cannot be reconciled with the formation of a metastable intermediate, such as the hypothetical polyoxide H2O4.In the last step beginning around 215 °K more peroxide is decomposed during the eutectic melting of the solid. Qualitatively these phenomena are similar to those shown by the condensate from dissociated water vapor.

An Investigation into the Analysis of Nitrogen for Hydrogen by Emission Spectroscopy

1964 ◽  
Vol 18 (5) ◽  
pp. 152-153 ◽  
Author(s):  
G. W. Dickinson ◽  
G. V. Wheeler
Keyword(s):  
Water Vapor ◽  
Experimental Work ◽  
Discharge Tube ◽  
Emission Spectroscopy ◽  
Continuous Monitoring ◽  
Cold Trap ◽  
Nitrogen Gas ◽  
Electrodeless Discharge ◽  
Grating Monochromator

Continuous monitoring of hydrogen in flowing nitrogen gas was needed in connection with experimental work at the USAEC's National Reactor Testing Station. One of the methods investigated was emission spectroscopy, using quartz envelope electrodeless discharge tube excitation. The sample gas was passed through a cold trap to eliminate water vapor and hydrocarbon vapors before entering the discharge tube at a pressure of two mm Hg. Using a grating monochromator with photomultiplier detection set at 4861.3A hydrogen can be determined down to about 0.05% (v/v).

New Design for a Differentially Pumped Hydration Chamber for a Siemens IA

1971 ◽  
Vol 29 ◽  
pp. 44-45
Author(s):  
R. C. Moretz ◽  
G. G. Hausner ◽  
D. F. Parsons
Keyword(s):  
Electron Microscopy ◽  
Water Vapor ◽  
Electron Diffraction ◽  
Water Vapor Pressure ◽  
Biological Materials ◽  
Thin Membrane ◽  
Reliable System ◽  
System A ◽  
Water Films ◽  
Aperture Opening

Electron microscopy and diffraction of biological materials in the hydrated state requires the construction of a chamber in which the water vapor pressure can be maintained at saturation for a given specimen temperature, while minimally affecting the normal vacuum of the remainder of the microscope column. Initial studies with chambers closed by thin membrane windows showed that at the film thicknesses required for electron diffraction at 100 KV the window failure rate was too high to give a reliable system. A single stage, differentially pumped specimen hydration chamber was constructed, consisting of two apertures (70-100μ), which eliminated the necessity of thin membrane windows. This system was used to obtain electron diffraction and electron microscopy of water droplets and thin water films. However, a period of dehydration occurred during initial pumping of the microscope column. Although rehydration occurred within five minutes, biological materials were irreversibly damaged. Another limitation of this system was that the specimen grid was clamped between the apertures, thus limiting the yield of view to the aperture opening.

Hydration Chamber for Jeolco 200 Kv Microscope

1970 ◽  
Vol 28 ◽  
pp. 542-543
Author(s):  
V. R. Matricardi ◽  
G. G. Hausner ◽  
D. F. Parsons
Keyword(s):  
Electron Microscope ◽  
Water Vapor ◽  
Vapor Pressure ◽  
Pressure Gradient ◽  
Room Temperature ◽  
List Type ◽  
Type Number ◽  
Equilibrium Vapor Pressure

In order to observe room temperature hydrated specimens in an electron microscope, the following conditions should be satisfied: The specimen should be surrounded by water vapor as close as possible to the equilibrium vapor pressure corresponding to the temperature of the specimen.The specimen grid should be inserted, focused and photo graphed in the shortest possible time in order to minimize dehydration.The full area of the specimen grid should be visible in order to minimize the number of changes of specimen required.There should be no pressure gradient across the grid so that specimens can be straddled across holes.Leakage of water vapor to the column should be minimized.

Warm and freeze-fracture of cotton seed radicles

1987 ◽  
Vol 45 ◽  
pp. 984-985
Author(s):  
E. L. Vigil ◽  
E. F. Erbe
Keyword(s):  
Thin Film ◽  
Water Vapor ◽  
Fracture Surface ◽  
Membrane Structure ◽  
Room Temperature ◽  
Freeze Fracture ◽  
Longitudinal Axis ◽  
Fracture Plane ◽  
Cotton Seeds ◽  
Condensed Water

In cotton seeds the radicle has 12% moisture content which makes it possible to prepare freeze-fracture replicas without fixation or cryoprotection. For this study we have examined replicas of unfixed radicle tissue fractured at room temperature to obtain data on organelle and membrane structure.Excised radicles from seeds of cotton (Gossyplum hirsutum L. M-8) were fractured at room temperature along the longitudinal axis. The fracture was initiated by spliting the basal end of the excised radicle with a razor. This procedure produced a fracture through the tissue along an unknown fracture plane. The warm fractured radicle halves were placed on a thin film of 100% glycerol on a flat brass cap with fracture surface up. The cap was rapidly plunged into liquid nitrogen and transferred to a freeze- etch unit. The sample was etched for 3 min at -95°C to remove any condensed water vapor and then cooled to -150°C for platinum/carbon evaporation.

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