The ignition and flame reactions of ethylene oxide

1949 ◽  
Vol 199 (1058) ◽  
pp. 328-351 ◽  
Keyword(s):  
Low Temperature ◽  
Ethylene Oxide ◽  
High Temperatures ◽  
Atmospheric Pressure ◽  
Ignition Limit ◽  
Constant Volume ◽  
Spontaneous Ignition ◽  
Ignition System ◽  
Cool Flames ◽  
Overall Reactions

Spontaneous ignition pressure-temperature relationships of ethylene oxide-oxygen and -air mixtures have been studied. A low-temperature ignition system exists and cool flames can be initiated in air at atmospheric pressure and below. The propagation of cool flames through cold mixtures imder this condition has not, however, been observed. Nevertheless, ethylene oxide itself propagates a decomposition flame and is inflammable at constant volume in admixture with air for all percentages above 3*6. The products of decomposition are almost entirely accounted for by the two overall reactions: C 2 H 4 0 = CH 4 + CO +17-2 kcal., 2C 2 H 4 0 = C 2 H 4 + 2CO + 2H 2 - 2 x 6-15 kcal. These reactions are also very significant in the non-luminous flames that have been found to be propagated through the richer mixtures of ethylene oxide with air. It is shown that the latter flames are initiated only at high temperatures, of the same order as for normal flames, and that they correspond with the non-luminous flames occurring near to the hightemperature spontaneous ignition limit of richer mixtures.

The spontaneous ignition of mixtures of n -heptane and 1-heptene in oxygen

1969 ◽  
Vol 311 (1505) ◽  
pp. 253-266 ◽  
Keyword(s):  
Stainless Steel ◽  
Binary Mixtures ◽  
High Temperatures ◽  
Spontaneous Ignition ◽  
Considerable Influence ◽  
Cool Flame ◽  
Cool Flames ◽  
Comparison Of The Results

Studies of the ignition in oxygen of binary mixtures of n -heptane and 1-heptene at tempera­tures below 400°C show that under all conditions investigated both hydrocarbons are consumed during ignition. However, below ca . 300°C, where 1-heptene is considerably less reactive than n -heptane, the alkene is not involved in the process leading to ignition and the ignitability of mixtures is controlled effectively by the concentration of the alkane. In con­trast, above 300 °C, 1-heptene is at least as ignitable as n -heptane and the alkene appears to contribute to the process leading to ignition. This shows that, although at relatively high temperatures conjugate alkenes maybe among the principal intermediates involved in the ignition of alkanes, this is not the case at lower temperatures. Here, the reaction between heptyl radicals and oxygen is additive leading to the formation of the corresponding heptylperoxy radicals and ignition then results from further reactions of these latter radicals. Comparison of the results obtained in stainless steel and vitreous vessels shows that the nature of the surface has little effect on limiting ignition pressures but does affect the multiplicity of cool flames. It thus appears that the surface exerts a considerable influence on the course of the reaction following the passage of a cool flame but not on the processes leading to the first cool flame and to ignition.

scholarly journals Dynamics of flow in albumin solution treated by low-temperature atmospheric pressure helium plasma jet

AIP Advances ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 125216
Author(s):  
Tetsuji Shimizu ◽  
Hiromasa Yamada ◽  
Masanori Fujiwara ◽  
Susumu Kato ◽  
Yuzuru Ikehara ◽  
...  
Keyword(s):  
Low Temperature ◽  
Atmospheric Pressure ◽  
Plasma Jet ◽  
Helium Plasma ◽  
Albumin Solution ◽  
Solution Treated

High phosphorus doping of epitaxial silicon at low temperature and atmospheric pressure

1991 ◽  
Vol 58 (17) ◽  
pp. 1896-1898 ◽  
Author(s):  
T. O. Sedgwick ◽  
P. D. Agnello ◽  
D. Nguyen Ngoc ◽  
T. S. Kuan ◽  
G. Scilla
Keyword(s):  
Low Temperature ◽  
Atmospheric Pressure ◽  
Epitaxial Silicon ◽  
Phosphorus Doping ◽  
High Phosphorus

Investigation of High Percentage Acetone-Butanol-Ethanol (ABE) Blended With Diesel in a Constant Volume Chamber

2014 ◽  
Author(s):  
Yilu Lin ◽  
Han Wu ◽  
Karthik Nithyanandan ◽  
Timothy H. Lee ◽  
Chia-fon F. Lee ◽  
...  
Keyword(s):  
Low Temperature ◽  
Ambient Temperature ◽  
Constant Volume ◽  
Low Temperature Combustion ◽  
Transportation Fuel ◽  
Promising Alternative ◽  
Alternative Transportation ◽  
Constant Volume Chamber ◽  
Temperature Combustion ◽  
Acetone Butanol Ethanol

Bio-butanol, a promising alternative transportation fuel, has its industrial-scale production hindered significantly by high cost component purification process from acetone-butanol-ethanol (ABE) broth. The purpose of this study is to investigate the possibility of using ABE-Diesel blends with high ABE percentages as an alternative transportation fuel. An optical-accessible constant volume chamber capable of controlling ambient temperature, pressure and oxygen concentration was used to mimic the environmental conditions inside a real diesel engine cylinder. ABE fuel with typical volumetric ratios of 30% acetone, 60% butanol and 10% ethanol were blended with ultra-low sulfur diesel at 80% vol. and were tested in this study. The ambient temperature was set to be at 1100K and 900K, which represents normal combustion conditions and low temperature combustion conditions respectively. The ambient oxygen concentrations were set to be at 21%, 16% and 11%, representing different EGR ratios. The in-cylinder pressure was recorded by using a pressure transducer and the time-resolved Mie-scattering image and natural flame luminosity was captured using a high-speed camera coupled with a copper vapor laser. The results show that the liquid penetration is reduced by the high percentage of ABE in the blends. At the same time, the soot formation is reduced significantly by increasing oxygen content in the ABE fuel. Even more interesting, a soot-free combustion was achieved by combining the low temperature combustion with the higher percentage ABE case. In terms of soot emission, high ABE ratio blends are a very promising alternative fuel to be directly used in diesel engines especially under low-temperature combustion conditions.

The Effect of Ge Segregation on Oxidation of Si

1987 ◽  
Vol 105 ◽  
Author(s):  
E. C. Frey ◽  
N. R. Parikh ◽  
M. L. Swanson ◽  
M. Z. Numan ◽  
W. K. Chu
Keyword(s):  
High Pressure ◽  
Low Temperature ◽  
Epitaxial Layer ◽  
Atmospheric Pressure ◽  
Oxidation Rate ◽  
Oxidation Temperature ◽  
Pressure Oxidation ◽  
Enhanced Oxidation ◽  
High Pressure Oxidation

AbstractWe have studied oxidation of various Si samples including: Ge implanted Si, CVD and MBE grown Si(0.4–4% Ge) alloys, and MBE grown Si-Si(Ge) superlattices. The samples were oxidized in pyrogenic steam (800–1000°C, atmospheric pressure) and at low temperature and high pressure (740°C, 205 atm of dry O2). The oxidized samples were analyzed with RBS/channeling and ellipsometry.An enhanced oxidation rate was seen for all Ge doped samples, compared with rates for pure Si. The magnitude of the enhancement increased with decreasing oxidation temperature. For steam oxidations the Ge was segregated from the oxide and formed an epitaxial layer at the Si-SiO2 interface; the quality of the epitaxy was highest for the highest oxidation temperatures. For high pressure oxidation the Ge was trapped in the oxide and the greatest enhancement in oxidation rate (>100%) was observed.

CO2 hydrogenation into CH4 over Ni–Fe catalysts

2018 ◽  
Vol 11 (03) ◽  
pp. 1850057 ◽  
Author(s):  
Reza Meshkini Far ◽  
Olena V. Ischenko ◽  
Alla G. Dyachenko ◽  
Oleksandr Bieda ◽  
Snezhana V. Gaidai ◽  
...  
Keyword(s):  
Low Temperature ◽  
Synergistic Effect ◽  
Atmospheric Pressure ◽  
High Efficiency ◽  
Co2 Hydrogenation ◽  
Hydrogenation Catalysts ◽  
Fe Catalysts ◽  
First Time ◽  
Supported Ni ◽  
Hydrogenation Of Co

Here, we report, for the first time, on the catalytic hydrogenation of CO2 to methane at atmospheric pressure. For the preparation of hydrogenation catalysts based on Ni and Fe metals, a convenient method is developed. According to this method, low-temperature reduction of the co-precipitated Ni and Fe oxides with hydrogen gives the effective and selective bimetallic Ni[Formula: see text]Fe[Formula: see text], Ni[Formula: see text]Fe[Formula: see text] and Ni[Formula: see text]Fe[Formula: see text] catalysts. At the temperature range of 300–400[Formula: see text]C, they exhibit a high efficiency of CH4 production with respect to monometallic Ni and Fe catalysts. The results imply a synergistic effect between Ni and Fe which caused the superior activity of the Ni[Formula: see text]Fe[Formula: see text] catalyst conversing [Formula: see text]% of CO2 into CH4 at 350[Formula: see text]C. To adapt the Ni–Fe catalysts in the industry, the effect of two different carriers on the efficiency of the alumina-supported Ni[Formula: see text]Fe[Formula: see text] catalyst was investigated. It is found that the Ni[Formula: see text]Fe[Formula: see text]/[Formula: see text]-Al2O3 catalyst effectively conversed CO2 giving 100% methane yield already at 275[Formula: see text]C.

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