The inhibiting effect of lead tetraethyl I. The effect of lead compounds on the vapour phase slow oxidation of di is opropyl ether and on the ignition of diethyl ether

1952 ◽  
Vol 215 (1121) ◽  
pp. 175-186 ◽  
Keyword(s):  
Diethyl Ether ◽  
Colloidal Particles ◽  
Vapour Phase ◽  
Slight Effect ◽  
Cool Flame ◽  
Lead Compounds ◽  
Inhibiting Effect ◽  
Lead Monoxide ◽  
Flame Ignition ◽  
Surface Destruction

The effect of lead tetraethyl on various pressure-temperature regions of ether combustion is described. The inhibiting effect was found to persist after prolonged evacuation of the apparatus. Various experiments suggested that this was due to the deposition of lead oxide. Work has therefore been carried out to determine the effects of the oxides of lead on the slow oxidation and on the ignition of ethers. It is found that lead monoxide gives an inhibiting effect profound, persistent and in every way similar to that of lead tetraethyl. Experiments show that it does this by a surface destruction of chain centres. It is further shown that, on oxidation, lead tetraethyl gives rise to a fog of (probably lead monoxide) particles. Its inhibiting effect is then exerted either by these colloidal particles or by the film of lead monoxide to which they give rise on the walls of the vessel. Lead tetraethyl and lead monoxide inhibit, at both ‘low’ and ‘high ’ temperatures, both the slow oxidation of di is opropyl ether and the process leading to hot flames of diethyl ether. They have no effect on the induction period preceding a cool flame in diethyl ether and only a slight effect on the cool-flame ignition limit. They both reduce the pressure kick due to a cool flame. These results are briefly discussed and are related to other published work.

scholarly journals Adaptation of n-heptane autoignition tabulation for complex chemistry mechanisms

2011 ◽  
Vol 15 (1) ◽  
pp. 135-144 ◽  
Author(s):  
Marko Ban ◽  
Neven Duic
Keyword(s):  
Reaction Rates ◽  
Chemical Mechanism ◽  
Cool Flame ◽  
Chemical Mechanisms ◽  
Compression Ignition Engines ◽  
Ignition Delay Times ◽  
Auto Ignition ◽  
Flame Ignition ◽  
Complex Chemistry ◽  
Effective Use

The adaptation of auto-ignition tabulation for effective use of complex chemical mechanisms will be presented in this paper. Taking cool flame ignition phenomenon into account could improve numerical simulations of combustion in compression ignition engines. Current approaches of successful simulation of this phenomenon are based on the extraction of ignition delay times, heat releases and also reaction rates from tabulated data dependant on four parameters: temperature, pressure, equivalence ratio and exhaust gasses mass fraction. The methods described here were used to create lookup tables including cool flame using a comprehensive chemical mechanism without including reaction rates data (as used by other authors). The method proved to be stable for creating tables and these results will be shown, as well as initial implementation results using the tables in computational fluid dynamics software.

Photolysis of diethyl ether in the vapour phase by 184.9 nm radiation

1981 ◽  
Vol 16 (2) ◽  
pp. 179-192 ◽  
Author(s):  
Hitoshi Mikuni ◽  
Makoto Takahasi
Keyword(s):  
Diethyl Ether ◽  
Vapour Phase

Infrared Spectrum of Two‐Stage Cool Flame of Diethyl Ether

1955 ◽  
Vol 23 (9) ◽  
pp. 1592-1596 ◽  
Author(s):  
Russell E. Donovan ◽  
William G. Agnew
Keyword(s):  
Infrared Spectrum ◽  
Diethyl Ether ◽  
Two Stage ◽  
Cool Flame

Effects of Indomethacin, Nimesulide, and Diclofenac on Human MG-63 Osteosarcoma Cell Line

2011 ◽  
Vol 14 (1) ◽  
pp. 98-107 ◽  
Author(s):  
Lourdes Díaz-Rodríguez ◽  
Olga García-Martínez ◽  
Manuel Arroyo- Morales ◽  
Laura Rodríguez-Pérez ◽  
Belén Rubio-Ruiz ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Line ◽  
Osteosarcoma Cell Line ◽  
Joint Diseases ◽  
Osteosarcoma Cell ◽  
Slight Effect ◽  
Inflammatory Joint Diseases ◽  
Inhibiting Effect ◽  
Inflammatory Drugs ◽  
Antigenic Profile

Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most widely prescribed drugs worldwide and serve as treatment of some degenerative inflammatory joint diseases. The aim of the present study was to investigate the influence of different concentrations of three NSAIDs on cell proliferation, differentiation, antigenic profile, and cell cycle in the human MG-63 osteosarcoma cell line, incubated for 24 hr. All NSAIDs had an inhibiting effect on osteoblastic proliferation. Treatments for 24 hr had small but significant effects on the antigenic profile. No treatment altered osteocalcin synthesis. Indomethacin and nimesulide treatments arrested the cell cycle at G0/G1. These results suggest that indomethacin, nimesulide, and diclofenac appear to have no effects on osteocalcin synthesis and a slight effect on the antigenic profile. They may delay bone regeneration due to their inhibiting effect on osteoblast growth. Therefore, these drugs should only be used in situations that do not require rapid bone healing.

Ultrastructure of Lymphatic Capillaries in the Transport of Colloidal Particles

1967 ◽  
Vol 25 ◽  
pp. 186-187
Author(s):  
L. V. Leak ◽  
J. F. Burke
Keyword(s):  
Connective Tissue ◽  
Colloidal Particles ◽  
Ultrastructural Level ◽  
Vital Role ◽  
Time Intervals ◽  
Thorium Dioxide ◽  
Lymphatic Capillary ◽  
Tissue Area ◽  
Rapid Removal ◽  
Tissue Fluids

The vital role played by the lymphatic capillaries in the transfer of tissue fluids and particulate materials from the connective tissue area can be demonstrated by the rapid removal of injected vital dyes into the tissue areas. In order to ascertain the mechanisms involved in the transfer of substances from the connective tissue area at the ultrastructural level, we have injected colloidal particles of varying sizes which range from 80 A up to 900-mμ. These colloidal particles (colloidal ferritin 80-100A, thorium dioxide 100-200 A, biological carbon 200-300 and latex spheres 900-mμ) are injected directly into the interstitial spaces of the connective tissue with glass micro-needles mounted in a modified Chambers micromanipulator. The progress of the particles from the interstitial space into the lymphatic capillary lumen is followed by observing tissues from animals (skin of the guinea pig ear) that were injected at various time intervals ranging from 5 minutes up to 6 months.

Deposited emulsion particles in the pores of aluminum oxide film

1978 ◽  
Vol 36 (1) ◽  
pp. 450-451
Author(s):  
Michio Ashida ◽  
Yasukiyo Ueda
Keyword(s):  
Oxide Film ◽  
Acid Solution ◽  
Barrier Layer ◽  
Colloidal Particles ◽  
Oxalic Acid Solution ◽  
Anodic Oxide ◽  
Anodic Oxide Film ◽  
Carbon Replica ◽  
Sectioning Method ◽  
Thin Sectioning

An anodic oxide film is formed on aluminum in an acidic elecrolyte during anodizing. The structure of the oxide film was observed directly by carbon replica method(l) and ultra-thin sectioning method(2). The oxide film consists of barrier layer and porous layer constructed with fine hexagonal cellular structure. The diameter of micro pores and the thickness of barrier layer depend on the applying voltage and electrolyte. Because the dimension of the pore corresponds to that of colloidal particles, many metals deposit in the pores. When the oxide film is treated as anode in emulsion of polyelectrolyte, the emulsion particles migrate onto the film and deposit on it. We investigated the behavior of the emulsion particles during electrodeposition.Aluminum foils (99.3%) were anodized in either 0.25M oxalic acid solution at 30°C or 3M sulfuric acid solution at 20°C. After washing with distilled water, the oxide films used as anode were coated with emulsion particles by applying voltage of 200V and then they were cured at 190°C for 30 minutes.

Characterization of GaAs/AlGaAs quantum wells and quantum wires by chemical lattice imaging

1994 ◽  
Vol 52 ◽  
pp. 736-737
Author(s):  
A. Carlsson ◽  
J.-O. Malm ◽  
A. Gustafsson
Keyword(s):  
Quantum Well ◽  
Quantum Wells ◽  
Quantum Wires ◽  
Vapour Phase ◽  
Quantitative Information ◽  
Lattice Imaging ◽  
Vapour Phase Epitaxy ◽  
Metalorganic Vapour Phase Epitaxy ◽  
High Resolution Images

In this study a quantum well/quantum wire (QW/QWR) structure grown on a grating of V-grooves has been characterized by a technique related to chemical lattice imaging. This technique makes it possible to extract quantitative information from high resolution images.The QW/QWR structure was grown on a GaAs substrate patterned with a grating of V-grooves. The growth rate was approximately three monolayers per second without growth interruption at the interfaces. On this substrate a barrier of nominally Al0.35 Ga0.65 As was deposited to a thickness of approximately 300 nm using metalorganic vapour phase epitaxy . On top of the Al0.35Ga0.65As barrier a 3.5 nm GaAs quantum well was deposited and to conclude the structure an additional approximate 300 nm Al0.35Ga0.65 As was deposited. The GaAs QW deposited in this manner turns out to be significantly thicker at the bottom of the grooves giving a QWR running along the grooves. During the growth of the barriers an approximately 30 nm wide Ga-rich region is formed at the bottom of the grooves giving a Ga-rich stripe extending from the bottom of each groove to the surface.

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