Sampler for Collection and Analysis of Low Vapor Pressure Chemical (LVPC) Particulates/Aerosols

2013 ◽  
Vol 85 (20) ◽  
pp. 9508-9513 ◽  
Author(s):  
K. J. Ewing ◽  
D. Gibson ◽  
J. Sanghera ◽  
F. Miklos
1938 ◽  
Vol 11 (3) ◽  
pp. 485-500
Author(s):  
R. L. Taylor ◽  
A. R. Kemp

Abstract THE presence of water is one of the principal causes of electrical instability in dielectric materials, often resulting in large variations in direct current resistance, dielectric constant, and power factor. A knowledge of the laws governing the sorption of water is therefore of considerable interest to the electrical and communications industries. The various investigators in the field of sorption of water by rubber have not reported their findings in a manner which will permit of consistent interpretation and correlation for engineering uses. Insufficient attention has been given to the effect of such factors as shape of test specimen, temperature control, variations in vapor pressure, chemical changes in the test specimen, etc. Consequently no sorption coefficient suitable for application to practical problems and no measure of the rate of sorption which will permit an adequate comparison of one material with another is now available. The purpose of this article is to describe the relation between rate of sorption and some of these variables, such as thickness of test specimen, temperature, and vapor pressure, and to show how sorption tests can be applied to certain practical problems. It is not the purpose to present a survey of the literature. The word “sorption” is used in conformity with current phraseology to mean the combined effect of adsorption and absorption.


RSC Advances ◽  
2020 ◽  
Vol 10 (63) ◽  
pp. 38227-38232
Author(s):  
Kentaro Yumigeta ◽  
Cassondra Brayfield ◽  
Hui Cai ◽  
Debarati Hajra ◽  
Mark Blei ◽  
...  

We report the synthesis of layered anisotropic semiconductor GeSe and GeSe2 nanomaterials through low temperature and atmospheric pressure chemical vapor deposition using halide based precursors. The crystal phase is controlled by simply changing selenium vapor pressure.


Author(s):  
A. C. Faberge

Benzylamine tartrate (m.p. 63°C) seems to be a better and more convenient substrate for making carbon films than any of those previously proposed. Using it in the manner described, it is easy consistently to make batches of specimen grids as open as 200 mesh with no broken squares, and without individual handling of the grids. Benzylamine tartrate (hereafter called B.T.) is a viscous liquid when molten, which sets to a glass. Unlike polymeric substrates it does not swell before dissolving; such swelling of the substrate seems to be a principal cause of breakage of carbon film. Mass spectroscopic examination indicates a vapor pressure less than 10−9 Torr at room temperature.


Author(s):  
V. R. Matricardi ◽  
G. G. Hausner ◽  
D. F. Parsons

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.


Author(s):  
Lisa A. Tietz ◽  
Scott R. Summerfelt ◽  
C. Barry Carter

Defects in thin films are often introduced at the substrate-film interface during the early stages of growth. The interface structures of semiconductor heterojunctions have been extensively studied because of the electrical activity of defects in these materials. Much less attention has been paid to the structure of oxide-oxide heterojunctions. In this study, the structures of the interfaces formed between hematite (α-Fe2O3) and two orientations of sapphire (α-Al2O3) are examined in relationship to the defects introduced into the hematite film. In such heterojunctions, the oxygen sublattice is expected to have a strong influence on the epitaxy; however, defects which involve only the cation sublattice may be introduced at the interface with little increase in interface energy.Oxide heterojunctions were produced by depositing small quantities of hematite directly onto electrontransparent sapphire substrates using low-pressure chemical vapor deposition. Prior to deposition, the ionthinned substrates were chemically cleaned and annealed at 1400°C to give “clean”, crystalline surfaces. Hematite was formed by the reaction of FeCl3 vapor with water vapor at 1150°C and 1-2 Torr. The growth of the hematite and the interface structures formed on (0001) and {102} substrates have been studied by bright-field, strong- and weak-beam dark-field imaging techniques.


1999 ◽  
Vol 09 (PR8) ◽  
pp. Pr8-395-Pr8-402 ◽  
Author(s):  
B. Armas ◽  
M. de Icaza Herrera ◽  
C. Combescure ◽  
F. Sibieude ◽  
D. Thenegal

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