Stationary flames of methyl nitrate and methyl nitrite

Methyl nitrate (CH 3 ONO 2 ) is the most explosive of the nitrate esters, and previous studies have been confined mainly to the slow thermal decomposition, and to the vapour phase explosion at low pressures in closed vessels. A stationary decomposition flame has now been maintained and studied spectrographically. A t low pressures the zones of reaction are clearly separated. From the early stages of the flame strong formaldehyde bands are emitted. This decomposition flame has been successfully simulated in artificial mixtures of methyl nitrite with oxygen. The results obtained are in accord with the preliminary fission of the nitrate molecule in the pre-heat zone of the flame: CH 3 ONO 2 →CH 3 O + NO 2 . The combustion flame of m ethyl nitrate with oxygen, nitric oxide and nitrogen dioxide has also been examined at low pressures. At atmospheric pressure, m ethyl nitrite (CH 3 ONO) has been found to support a decomposition flame of very small burning velocity. However, the combustion of m ethyl nitrite with oxygen at atmospheric pressure is an extremely fast and vigorous flame. It has been observed in both pre-mixed and diffusion systems and information about the changes occurring in it have been obtained by absorption and emission spectroscopy. All the experimental results may be interpreted in terms of two general principles: the reluctance of nitric oxide to react except at high temperatures and pressures and the frequent occurrence in flames of extensive pyrolytic reactions before the main reaction zone is reached.

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THE REACTIONS OF ELECTRONICALLY EXCITED NITRIC OXIDE MOLECULES WITH HYDROCARBONS

Canadian Journal of Chemistry ◽

10.1139/v63-169 ◽

1963 ◽

Vol 41 (5) ◽

pp. 1207-1222 ◽

Cited By ~ 19

Author(s):

O. P. Strausz ◽

H. E. Gunning

Keyword(s):

Nitric Oxide ◽

Room Temperature ◽

Circulatory System ◽

Average Chain Length ◽

Primary Process ◽

Reaction Products ◽

Electronically Excited ◽

Yield Values ◽

Methyl Nitrate ◽

Ethyl Nitrite

The reactions of NO(4II) molecules, generated by Hg 6(3P1) photosensitization, with methane, ethane, propane, neopentane, and benzene have been studied at room temperature in a circulatory system. In the case of ethane the following reaction products were identified: N2, N2O, H2O, NO2, CO, CO2, C2H4, acetaldehyde, nitroethane, ethyl nitrite, ethyl nitrate, nitroethylene, nitromethane, methyl nitrite, methyl nitrate, formaldehyde. For hydrocarbon consumption, under comparable conditions, the following quantum yield values were established: [Formula: see text]. The most probable primary process may be represented by the sequence[Formula: see text] [Formula: see text]Alkyl free radicals catalyze the chain disproportionation of nitric oxide at room temperature according to the stoichiometric equation[Formula: see text]A minimal value of 12 was established for the average chain length.

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Cold Atmospheric Pressure Plasma-Activated Medium Induces Selective Cell Death in Human Hepatocellular Carcinoma Cells Independently of Singlet Oxygen, Hydrogen Peroxide, Nitric Oxide and Nitrite/Nitrate

International Journal of Molecular Sciences ◽

10.3390/ijms22115548 ◽

2021 ◽

Vol 22 (11) ◽

pp. 5548

Author(s):

Yan Li ◽

Tianyu Tang ◽

Haejune Lee ◽

Kiwon Song

Keyword(s):

Nitric Oxide ◽

Cell Death ◽

Singlet Oxygen ◽

Atmospheric Pressure ◽

Atmospheric Pressure Plasma ◽

Proliferative Effect ◽

Huh7 Cells ◽

Anti Cancer ◽

Cold Atmospheric Pressure Plasma ◽

Nitrite Nitrate

Cold atmospheric pressure plasma (CAP) and plasma-activated medium (PAM) induce cell death in diverse cancer cells and may function as powerful anti-cancer agents. The main components responsible for the selective anti-cancer effects of CAP and PAM remain elusive. CAP or PAM induces selective cell death in hepatocellular carcinoma cell lines Hep3B and Huh7 containing populations with cancer stem cell markers. Here, we investigated the major component(s) of CAP and PAM for mediating the selective anti-proliferative effect on Hep3B and Huh7 cells. The anti-proliferative effect of CAP was mediated through the medium; however, the reactive oxygen species scavenger N-acetyl cysteine did not suppress PAM-induced cell death. Neither high concentrations of nitrite or nitrite/nitrate nor a low concentration of H2O2 present in the PAM containing sodium pyruvate affected the viability of Hep3B and Huh7 cells. Inhibitors of singlet oxygen, superoxide anions, and nitric oxide retained the capacity of PAM to induce anti-cancer effects. The anti-cancer effect was largely blocked in the PAM prepared by placing an aluminum metal mesh, but not a dielectric PVC mesh, between the plasma source and the medium. Hence, singlet oxygen, hydrogen peroxide, nitric oxide, and nitrite/nitrate are not the main factors responsible for PAM-mediated selective death in Hep3B and Huh7 cells. Other factors, such as charged particles including various ions in CAP and PAM, may induce selective anti-cancer effects in certain cancer cells.

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Oxidation of Si(100) in nitric oxide at low pressures: An x-ray photoelectron spectroscopy study

Applied Physics Letters ◽

10.1063/1.119307 ◽

1997 ◽

Vol 70 (1) ◽

pp. 63-65 ◽

Cited By ~ 44

Author(s):

A. Kamath ◽

D. L. Kwong ◽

Y. M. Sun ◽

P. M. Blass ◽

S. Whaley ◽

...

Keyword(s):

Nitric Oxide ◽

Photoelectron Spectroscopy ◽

Spectroscopy Study ◽

X Ray ◽

Low Pressures

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The rate of evaporation of droplets. Evaporation and diffusion coefficients, and vapour pressures of dibutyl phthalate and butyl stearate

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

10.1098/rspa.1946.0050 ◽

1946 ◽

Vol 186 (1006) ◽

pp. 368-390 ◽

Cited By ~ 54

Keyword(s):

Diffusion Coefficients ◽

Atmospheric Pressure ◽

Dibutyl Phthalate ◽

Droplet Evaporation ◽

Medium Size ◽

Good Accordance ◽

Butyl Stearate ◽

Rate Of Evaporation ◽

Low Pressures ◽

And Diffusion

The rate of evaporation of drops of dibutyl phthalate and butyl stearate of radius approx. 0.5 mm. has been studied by means of a microbalance over a range of atmospheric pressures down to approx. 0*1 mm. of mercury. Wide departures from Langmuir’s evaporation formula were found to occur at these low pressures, but results are in good accordance with the theory of droplet evaporation advanced by Fuchs which hitherto has not been tested experimentally. This experimental verification of Fuch’s theory for droplets of medium size evaporating at low pressures shows that the theory can be applied to the evaporation of very small drops at atmospheric pressure. The vapour pressures of the above liquids have been measured by Knudsen’s method and the evaporation and diffusion coefficients calculated fro n the experimental data.

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Reaction Model Development of Selected Aromatics as Relevant Molecules of a Kerosene Surrogate – The Importance of M-Xylene Within the Combustion of 1,3,5-Trimethylbenzene

10.1115/gt2021-60093 ◽

2021 ◽

Author(s):

Astrid Ramirez Hernandez ◽

Trupti Kathrotia ◽

Torsten Methling ◽

Marina Braun-Unkhoff ◽

Uwe Riedel

Keyword(s):

Atmospheric Pressure ◽

Burning Velocity ◽

Model Development ◽

Kinetic Mechanism ◽

Chemical Kinetic ◽

Reaction Model ◽

Pollutant Emissions ◽

Similar Species ◽

Ignition Delay Times ◽

Wide Range

Abstract The development of advanced reaction models to predict pollutant emissions in aero-engine combustors usually relies on surrogate formulations of a specific jet fuel for mimicking its chemical composition. 1,3,5-trimethylbenzene is one of the suitable components to represent aromatics species in those surrogates. However, a comprehensive reaction model for 1,3,5-trimethylbenzene combustion requires a mechanism to describe the m-xylene oxidation. In this work, the development of a chemical kinetic mechanism for describing the m-xylene combustion in a wide parameter range (i.e. temperature, pressure, and fuel equivalence ratios) is presented. The m-xylene reaction submodel was developed based on existing reaction mechanisms of similar species such as toluene and reaction pathways adapted from literature. The sub-model was integrated into an existing detailed mechanism that contains the kinetics of a wide range of n-paraffins, iso-paraffins, cyclo-paraffins, and aromatics. Simulation results for m-xylene were validated against experimental data available in literature. Results show that the presented m-xylene mechanism correctly predicts ignition delay times at different pressures and temperatures as well as laminar burning velocities at atmospheric pressure and various fuel equivalence ratios. At high pressure, some deviations of the calculated laminar burning velocity and the measured values are obtained at stoichiometric to rich equivalence ratios. Additionally, the model predicts reasonably well concentration profiles of major and intermediate species at different temperatures and atmospheric pressure.

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Nitric Oxide Reduction in Methyl Nitrite Pyrolysis and the Transition from Isothermal Decomposition to Adiabatic Flame

Nature ◽

10.1038/188056a0 ◽

1960 ◽

Vol 188 (4744) ◽

pp. 56-56 ◽

Cited By ~ 11

Author(s):

PETER GRAY ◽

A. WILLIAMS

Keyword(s):

Nitric Oxide ◽

Isothermal Decomposition ◽

Oxide Reduction ◽

Methyl Nitrite ◽

Nitric Oxide Reduction

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The influence of pressure on the boiling points of metals

Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character ◽

10.1098/rspa.1910.0037 ◽

1910 ◽

Vol 83 (565) ◽

pp. 483-491 ◽

Cited By ~ 9

Keyword(s):

Atmospheric Pressure ◽

Boiling Point ◽

High Vacuum ◽

Similar Type ◽

Exact Relation ◽

Reduced Pressure ◽

Boiling Points ◽

Experimental Values ◽

Low Pressures ◽

Very High

Part I. — Pressures below 760 mm . In a previous communication (‘Proc.’, A, vol. 82, 1909, p. 396) the approximate boiling points of a number of metals were determined at atmospheric pressure. Apart from the question of finding the exact relation between the boiling point and pressure, it is an important criterion of any method for fixing the temperatures of ebullition to demonstrate that the experimental values obtained are dependent on the pressure. It is specially desirable when dealing with substances boiling at temperatures above 2000° to have some evidence that the points indicated are true boiling points. Previous work on the vaporisation of metals at different pressures has been confined to experiments in a very high vacuum except for metals like bismuth, cadmium, and zinc, which boil at relatively low temperatures under atmospheric pressure. The observations were limited to very low pressures on account of the difficulty of obtaining any material capable of withstanding a vacuum at temperatures over 1400° and the consequent necessity for keeping the boiling point below this limit by using very low pressures. Moreover in the case of the majority of the metals, e. g. , copper, tin, ebullition under reduced pressure has never been observed. The difficulties indicated above were avoided by using a similar type of apparatus to that previously described, and arranging the whole furnace inside a vacuum enclosure, thus permitting of the use of graphite crucibles to contain the metal.

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