Volatility of Antioxidants and Antiozonants. 1. Pure Compounds in Absence of Rubber

1964 ◽  
Vol 37 (1) ◽  
pp. 210-220 ◽  
Author(s):  
R. B. Spacht ◽  
W. S. Hollingshead ◽  
H. L. Bullard ◽  
D. C. Wills
Keyword(s):  
Vapor Pressure ◽  
Aromatic Amine ◽  
Quantitative Data ◽  
Surface Effects ◽  
Vapor Pressures ◽  
Pure Compounds ◽  
Different Temperatures ◽  
Amine Compounds

Abstract Comparable volatility data are presented for three phenolic and five aromatic amine compounds. Vapor pressure curves for the materials are given along with the vapor pressure equations derived from these curves. The equations are used to calculate temperatures at which the eight compounds would have equal vapor pressure. Vapor pressures of each material are calculated at specified temperatures. Data are given for several methods of determining actual losses of antioxidants at several different temperatures and at several different airflows. Surface effects are also studied. In general, all methods give the same relative rating of the eight materials, but quantitative data vary considerably with the method used.

Triallate Vapor Pressure and Volatilization from Glass Surfaces

Weed Science ◽  
1978 ◽  
Vol 26 (5) ◽  
pp. 505-508 ◽  
Author(s):  
R. Grover ◽  
W. F. Spencer ◽  
W. J. Farmer ◽  
T. D. Shoup
Keyword(s):  
Vapor Pressure ◽  
Vapor Pressures ◽  
Vapor Density ◽  
Technical Grade ◽  
Density Measurements ◽  
Vapor Flux ◽  
Solid Adsorbent ◽  
Different Temperatures ◽  
Glass Surfaces ◽  
The Relationship

Vapor pressures of technical-grade triallate [S-(2,3,3-trichloroallyl)diisopropylthiocarbamate] were calculated from the vapor density measurements determined at seven different temperatures, using a gas-saturation technique and solid adsorbent traps. The equation Log10P = 11.05 – (4401/T) delineated the relationship between the apparent vapor pressure and temperature, giving the triallate vapor pressure values from 1.083 × 10−4to 16.371 × 10−4mm Hg over the temperature range of 20 to 45 C. The vapor flux of triallate from glass surfaces was of the order of 5.7 μg cm−2h−1at 25 C.

scholarly journals Experimental and Theoretical Study of the Enthalpy of Formation of 3,6-Diphenyl-1,2,4,5-Tetroxane Molecule

2002 ◽  
Vol 2 ◽  
pp. 455-460 ◽  
Author(s):  
N.L. Jorge ◽  
L.C.A. Leiva ◽  
M.G. Castellanos ◽  
M.E. Gomez Vara ◽  
L.F.R. Cafferata ◽  
...  
Keyword(s):  
Vapor Pressure ◽  
Enthalpy Of Formation ◽  
Vapor Phase ◽  
Theoretical Study ◽  
Theoretical Calculations ◽  
Basis Set ◽  
Sublimation Enthalpy ◽  
Combustion Heat ◽  
Different Temperatures ◽  
The Enthalpy Of Formation

We report the results obtained for the experimental determination and the theoretical calculation of the enthalpy of formation of 3,6-diphenyl-1,2,4,5-tetroxane molecule. The experimental work was performed using a macrocalorimeter to measure the combustion heat, and the sublimation enthalpy was determined via the measurement of the vapor pressure at equilibrium with the vapor phase at different temperatures resorting to the Clapeyron-Claussius equation. Theoretical calculations were performed using semiempirical AM1 and PM3 methods as well asab initiotechniques at the 3-21, 6-31G(d,p), and 6-311G(d,p) basis set levels.

Preparation of matched reagents for use with the Scholander gas analyzer

1977 ◽  
Vol 43 (1) ◽  
pp. 164-166
Author(s):  
R. G. Collins ◽  
V. W. Musasche ◽  
E. T. Howley
Keyword(s):  
Water Vapor ◽  
Vapor Pressure ◽  
Volume Change ◽  
Quantitative Method ◽  
Gas Analysis ◽  
Vapor Pressures ◽  
Gas Analyzer ◽  
Atmospheric Air ◽  
Fixed Acid

Scholander's method of gas analysis requires that the solutions for CO2 absorber, O2 absorber, and acid-rinse be matched in terms of water vapor tension throughout the analysis. Any difference in vapor pressure between either or both of the absorbing solutions and the indicator drop (composed of acid-rinse) will produce a measurable volume change which cannot be attributed to the presence of absorbable gases. This paper describes a practical and quantitative method for preparing reagents whose vapor pressures are matched. A fixed acid-rinse formulation was used throughout. A CO2 absorber prepared from 1.35 N KOH and an O2 absorber prepared from 0.76 N KOH were both matched in terms of vapor pressure with Scholander's acid-rinse solution. Analysis of atmospheric air provided a check on the accuracy of the technique. The values obtained were O2 20.94%, CO2 0.03%, and N2 (balance) 79.04%.

Influence of Nano-Refrigeration-Oil on Saturated Vapor Pressure of R22

2011 ◽  
Vol 694 ◽  
pp. 309-314 ◽  
Author(s):  
Jiang Feng Lou ◽  
Rui Xiang Wang ◽  
Min Zhang
Keyword(s):  
Experimental Data ◽  
Vapor Pressure ◽  
Mass Fraction ◽  
Saturated Vapor Pressure ◽  
Saturated Vapor ◽  
Experimental Results ◽  
Vapor Pressures ◽  
Temperature Range ◽  
Mass Fractions

The saturated vapor pressures of R22 uniformly mixed with refrigeration oil and nano- refrigeration-oil were measured experimentally at a temperature range from 263 to 333K and mass fractions from 1 to 5%. The experimental results showed that the saturated vapor pressure of R22/KT56 mixture was lower than that of pure R22; the pressure deviation between them increased with a raising mass fraction of refrigeration oil and temperature. After adding nano-NiFe2O4 and nano-fullerene into KT56, the pressure deviation increased at the same mass fraction and temperature. A saturated vapor pressure correlation for R22 and refrigeration oil/nano-refrigeration-oil mixture was proposed, and the calculated values agreed with the experimental data within the deviation of ± 0.77%.

PRELIMINARY STUDY OF THE FRACTIONATION OF ISOTOPIC ISOMERS BY DISTILLATION

1935 ◽  
Vol 13b (2) ◽  
pp. 114-121 ◽  
Author(s):  
D. F. Stedman
Keyword(s):  
Vapor Pressure ◽  
Boiling Point ◽  
Atomic Weight ◽  
Liquid Oxygen ◽  
Vapor Pressures ◽  
Normal Concentration ◽  
Short Run ◽  
Total Separation ◽  
Preliminary Study

Slight separations of some isotopic isomers have been achieved by equilibrium rectification. In the case of chlorine the total separation amounted to 0.048 atomic weight units; 28.6% of the O18 has also been removed from normal oxygen by the fractionation of water, and in a short run with liquid oxygen the normal concentration of O18 has been raised from 0.2% to 0.25%. The last-mentioned separation can be carried considerably further with present equipment.CH3D was synthesized. Its boiling point appears to be 0.5 °C. lower than that of methane.The vapor pressures of a 56.8% solution of D2O were measured, and it is suggested that the published values of the vapor pressure of D2O at temperatures lower than 40 °C. may be slightly too high.

High Temperature Sulphidation Behavior of Fe20Cr6Al-Y,Hf Steel

2008 ◽  
Vol 595-598 ◽  
pp. 763-768
Author(s):  
Martah Homa ◽  
Zbigniew Żurek
Keyword(s):  
High Temperature ◽  
Chemical Composition ◽  
Vapor Pressure ◽  
Phase Analysis ◽  
High Temperature Corrosion ◽  
Vapor Pressures ◽  
Scale Layer ◽  
Phase And Chemical Composition ◽  
Xrd Techniques ◽  
Scale Surface

The high temperature corrosion behavior of Fe20Cr6Al-Y,Hf steel was studied in the range of temperature 800-1000oC in H2/H2S atmospheres at pS2=10-2 ,10-3 and 10-4 Pa sulphur vapor pressures. Kinetics depend on the temperature and sulphur vapor pressure. After 24 hours the whole specimen was practically consumed because the samples were 0,06 cm thick. Morphology of the scales have been performed by SEM techniques. Phase and chemical composition have been studied by EDX and XRD techniques. It was found that scale formed on Fe20Cr6Al-Y,Hf alloy was built with porosity sulphides layer. EDX analysis of the scale surface show that the any aluminum, hafnium and yttrium sulfides were found in the formed scale layer, however small amounts of Al2S3 was detected in scale/steel interface. Also internal sulphidation was observed. A phase analysis of the formed scale revealed that it is composed mainly of an FeS, Fe7S8 phases and CrS, Cr5S6. Result were compared with data obtained on the pure Fe and Cr samples.

scholarly journals Technical Note: Vapor pressure estimation methods applied to secondary organic aerosol constituents from α-pinene oxidation: an intercomparison study

2010 ◽  
Vol 10 (13) ◽  
pp. 6271-6282 ◽  
Author(s):  
S. Compernolle ◽  
K. Ceulemans ◽  
J.-F. Müller
Keyword(s):  
Vapor Pressure ◽  
Functional Groups ◽  
State Of The Art ◽  
Organic Aerosol ◽  
Technical Note ◽  
Estimation Methods ◽  
Vapor Pressures ◽  
Aerosol Formation ◽  
Pressure Estimation ◽  
Intercomparison Study

Abstract. We applied and compared seven vapor pressure estimation methods to the condensable compounds generated in the oxidation of α-pinene, as described by the state-of-the-art mechanism of the BOREAM model Capouet et al., 2008. Several of these methods had to be extended in order to treat functional groups such as hydroperoxides and peroxy acyl nitrates. Large differences in the estimated vapor pressures are reported, which will inevitably lead to large differences in aerosol formation simulations. Cautioning remarks are given for some vapor pressure estimation methods.

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