A kinetics and dynamics study on the auto-ignition of dimethyl ether at low temperatures and low pressures

2020 ◽  
Author(s):  
Wenlin Huang ◽  
Qian Zhao ◽  
Zuohua Huang ◽  
Henry J. Curran ◽  
Yingjia Zhang
Keyword(s):  
Dimethyl Ether ◽  
Low Temperatures ◽  
Auto Ignition ◽  
Kinetics And Dynamics ◽  
Low Pressures

Dolomite Decomposition to (Ca,Mg)O Solid Solutions: An X-Ray Diffraction Study.Part II.

1984 ◽  
Vol 39 (10) ◽  
pp. 981-985 ◽  
Author(s):  
G. Spinolo ◽  
U. Anselmi Tamburini
Keyword(s):  
Free Energy ◽  
Low Temperatures ◽  
Particle Sizes ◽  
Diffusional Process ◽  
X Ray Diffraction ◽  
High Iron Content ◽  
X Ray ◽  
Energy Of Mixing ◽  
Free Energy Of Mixing ◽  
Low Pressures

Abstract The full decomposition of dolomites with low and high iron content at low temperatures and low pressures is discussed with reference to the free energy of mixing of the ternary system Ca. Fe, Mg/O. The actual products of the primary step are a couple of rock salt structured oxides close to the spinodal compositions and with very small particle sizes. A subsequent diffusional process can produce large crystallites with equilibrium compositions, but it is effective only when either a low-iron dolomite is used as starting material or higher temperatures are employed.

THE THERMAL DECOMPOSITION OF HYDROGEN PEROXIDE VAPOUR. II.

1947 ◽  
Vol 25b (2) ◽  
pp. 135-150 ◽  
Author(s):  
Paul A. Giguère
Keyword(s):  
Activation Energy ◽  
Hydrogen Peroxide ◽  
Thermal Decomposition ◽  
Low Temperatures ◽  
Hydrocyanic Acid ◽  
Quartz Surface ◽  
First Order ◽  
Acid Washing ◽  
Reaction Vessels ◽  
Low Pressures

The decomposition of hydrogen peroxide vapour has been investigated at low pressures (5 to 6 mm.) in the temperature range 50° to 420 °C., for the purpose of determining the effect of the nature and treatment of the active surfaces. The reaction was followed in an all-glass apparatus and, except in one case, with one-litre round flasks as reaction vessels. Soft glass, Pyrex, quartz, and metallized surfaces variously treated were used. In most cases the decomposition was found to be mainly of the first order but the rates varied markedly from one vessel to another, even with vessels made of the same type of glass. On a quartz surface the decomposition was preceded by an induction period at low temperatures. Fusing the glass vessels slowed the reaction considerably and increased its apparent activation energy; this effect was destroyed by acid washing. Attempts to poison the surface with hydrocyanic acid gave no noticeable result. The marked importance of surface effects at all temperatures is considered as an indication that the reaction was predominantly heterogeneous under the prevailing conditions. Values ranging from 8 to 20 kcal. were found for the apparent energy of activation. It is concluded that the decomposition of hydrogen peroxide vapour is not very specific as far as the nature of the catalyst is concerned.

FREE RADICALS BY MASS SPECTROMETRY: XXII. PRIMARY DECOMPOSITION STEPS IN THE MERCURY-PHOTOSENSITIZED DECOMPOSITION OF METHANOL AND DIMETHYL ETHER

1961 ◽  
Vol 39 (1) ◽  
pp. 102-109 ◽  
Author(s):  
R. F. Pottie ◽  
A. G. Harrison, ◽  
F. P. Lossing
Keyword(s):  
Mass Spectrometry ◽  
Free Radicals ◽  
Dimethyl Ether ◽  
Excited Molecule ◽  
Primary Decomposition ◽  
Oh Radicals ◽  
No Formation ◽  
Abstraction Reaction ◽  
Reaction Proceeds ◽  
Low Pressures

The Hg 3P1 photosensitized decomposition of methanol at low pressures proceeds mainly by a dissociation into CH3O radicals and H atoms. No formation of CH2OH radicals is observed. A subsidiary reaction to form CH3 and OH may also be a primary step. Formation of CH2OH radicals at higher pressures is attributed to an abstraction reaction of CH3O with CH3OH.Two primary modes of dissociation are found to occur for dimethyl ether:[Formula: see text]The relative probabilities of occurrence at low pressures are ∼45% and ∼50%, respectively. The possibility that the second reaction proceeds by formation of an excited molecule is discussed.

The Operational Monitor of Air-Conditioners by Using Probabilistic Neural Network

2014 ◽  
Vol 540 ◽  
pp. 411-415
Author(s):  
Sung Ling Chen ◽  
Ming Tang Tsai
Keyword(s):  
Neural Network ◽  
Low Temperatures ◽  
Field Data ◽  
Probabilistic Neural Network ◽  
Dynamic Environment ◽  
Test Results ◽  
Data Set ◽  
Air Conditioners ◽  
Operation Conditions ◽  
Low Pressures

This paper uses the probabilistic neural network (PNN) to monitor the operation statues for the compressor of air-conditioners. The field data including the high/low pressures and the high/low temperatures of refrigerants are measured in a practical system. PNN analyses the refrigerants’ pressures/temperatures of air-conditioners to monitor the operation conditions of compressor. PNN method is suitable for application in a dynamic environment by using new data-set and new hidden without doing any computed iteration. Computer simulations were conducted with refrigerants’ records, test results showed the effectiveness of the proposed system.

Sign in / Sign up

Export Citation Format

Share Document