Survival of Mammals Breathing Organic Liquids Equilibrated with Oxygen at Atmospheric Pressure

The critical surface tension of wool fibers was measured using the sink-float technique with various classes of test liquids. Nonpolar organic liquids and aqueous surfactants gave similar values of γ, but much lower values were obtained with butanol/water mixtures. Adsorption of butanol on the surface of the fibers is thought to be responsible for the low values of γ in the latter case. Removal of lipid material from the surface of fibers by extraction increases γ from 30 mN/m to 37 mN/m, similar to that obtained for horn keratin or polypeptide material. Exposure of fibers to a corona discharge in air at atmospheric pressure also increases γ.

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Permeability Measurement of some Barrier Materials as a Function of Temperature and Pressure

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.510-511.602 ◽

2012 ◽

Vol 510-511 ◽

pp. 602-608

Author(s):

M. Maqsood ◽

S. Faisal ◽

J. Ali ◽

A. Usman ◽

K. Alamgir ◽

...

Keyword(s):

Atmospheric Pressure ◽

Gas Flow ◽

Flow System ◽

Organic Liquids ◽

Barrier Materials ◽

Helium Gas ◽

Back Ground ◽

Different Temperatures ◽

Pure Helium ◽

Temperature And Pressure

Barrier materials possess the ability to restrict the passage of gases, vapors, and organic liquids through their boundaries. These barrier materials have large number of applications in industry and scientific research. To measure the permeability of barrier materials, a specific gas flow system has been developed, pure helium gas is used to measure the back ground reading through SS-316. The permeability and break-through time has been measured through Inconel X-750, NBR and Viton below and above the atmospheric pressure and at different temperatures 20°C, 40°C and 70°C.

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Viscosities of liquids at constant volume

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1951.0069 ◽

1951 ◽

Vol 206 (1085) ◽

pp. 257-274 ◽

Cited By ~ 32

Keyword(s):

Activation Energy ◽

High Pressure ◽

Viscous Flow ◽

Atmospheric Pressure ◽

General Relation ◽

Constant Volume ◽

Organic Liquids ◽

True Activation Energy ◽

Straight Line ◽

Volume Range

The design and construction of a falling-cylinder viscometer for use at pressures up to 3000 atm. are described. The instrument has been employed for the first direct measurement of the variation of the viscosity of a liquid with temperature at a constant volume which is determined by the density of the liquid at the temperature at which the high-pressure vessel is filled and sealed. Preliminary measurements are reported on benzene and carbon tetra-chloride. The results have confirmed experimentally the straight-line relation between log η and 1/ T at constant volume as predicted in the viscosity theories of Andrade (1934 a , b ) and Eyring, Glasstone & Laidler (1941, chap. IX). Further confirmation has been obtained by combining some recent atmospheric pressure viscosity measurements at very low temperatures (Giller & Drickamer 1949) with existing high-pressure and compressibility data. E v , the energy of activation of viscous flow at constant volume, has been calculated over a wide volume range and its importance is discussed. For many simple organic liquids, there appears to be a simple general relation between E v and volume. E v is considered to be the ‘true’ activation energy of viscous flow and its relation to E vis , the quantity usually described as the activation energy of viscous flow, calculated from the variation of the viscosity with temperature at constant (atmospheric) pressure, is discussed.

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A High-Voltage Terminal for a Field-Emission Gun

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010009539x ◽

1972 ◽

Vol 30 ◽

pp. 428-429

Author(s):

N. F. Ziegler

Keyword(s):

Field Emission ◽

High Voltage ◽

Atmospheric Pressure ◽

Power Supplies ◽

High Coherence

A high-voltage terminal has been constructed for housing the various power supplies and metering circuits required by the field-emission gun (described elsewhere in these Proceedings) for the high-coherence microscope. The terminal is cylindrical in shape having a diameter of 14 inches and a length of 24 inches. It is completely enclosed by an aluminum housing filled with Freon-12 gas at essentially atmospheric pressure. The potential of the terminal relative to ground is, of course, equal to the accelerating potential of the microscope, which in the present case, is 150 kilovolts maximum.

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Electron microscope characterization of MOCVD-grown gap layers on Si

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100144991 ◽

1986 ◽

Vol 44 ◽

pp. 724-725

Author(s):

K.M. Jones ◽

M.M. Al-Jassim ◽

J.M. Olson

Keyword(s):

Atmospheric Pressure ◽

Vapour Deposition ◽

Chemical Vapour ◽

Organic Chemical ◽

Lattice Match ◽

Si Substrates ◽

Metal Organic ◽

Good Lattice ◽

Antiphase Domains

The epitaxial growth of III-V semiconductors on Si for integrated optoelectronic applications is currently of great interest. GaP, with a lattice constant close to that of Si, is an attractive buffer between Si and, for example, GaAsP. In spite of the good lattice match, the growth of device quality GaP on Si is not without difficulty. The formation of antiphase domains, the difficulty in cleaning the Si substrates prior to growth, and the poor layer morphology are some of the problems encountered. In this work, the structural perfection of GaP layers was investigated as a function of several process variables including growth rate and temperature, and Si substrate orientation. The GaP layers were grown in an atmospheric pressure metal organic chemical vapour deposition (MOCVD) system using trimethylgallium and phosphine in H2. The Si substrates orientations used were (100), 2° off (100) towards (110), (111) and (211).

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Microstructure and reactivity of small metal particles: The role of Ce additives

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100121995 ◽

1992 ◽

Vol 50 (1) ◽

pp. 318-319

Author(s):

L.D. Schmidt ◽

K. R. Krause ◽

J. M. Schwartz ◽

X. Chu

Keyword(s):

Atmospheric Pressure ◽

Noble Metals ◽

Mixed Oxides ◽

Catalytic Properties ◽

Chemical Shifts ◽

Catalytic Converter ◽

Structural Evolution ◽

Single Particles ◽

Small Metal Particles

The evolution of microstructures of 10- to 100-Å diameter particles of Rh and Pt on SiO2 and Al2O3 following treatment in reducing, oxidizing, and reacting conditions have been characterized by TEM. We are able to transfer particles repeatedly between microscope and a reactor furnace so that the structural evolution of single particles can be examined following treatments in gases at atmospheric pressure. We are especially interested in the role of Ce additives on noble metals such as Pt and Rh. These systems are crucial in the automotive catalytic converter, and rare earths can significantly modify catalytic properties in many reactions. In particular, we are concerned with the oxidation state of Ce and its role in formation of mixed oxides with metals or with the support. For this we employ EELS in TEM, a technique uniquely suited to detect chemical shifts with ∼30Å resolution.

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