Synthesis of the principal chain of the o-antigenic polysaccharides ofShigella flexneri. Communication 6. Synthesis of the monomer, its polycondensation, and properties of the polysaccharide

1985 ◽  
Vol 34 (5) ◽  
pp. 1051-1056
Author(s):  
N. �. Bairamova ◽  
Yu. E. Tsvetkov ◽  
L. V. Bakinovskii ◽  
N. K. Kochektov
Keyword(s):  
Principal Chain

scholarly journals The mechanism of the hydrogen-oxygen reaction - IV. The activation energy of the initiating process

1946 ◽  
Vol 186 (1007) ◽  
pp. 462-469 ◽  
Keyword(s):  
Activation Energy ◽  
Temperature Coefficient ◽  
Thermal Reaction ◽  
Hydrogen Atoms ◽  
Production Of Hydrogen ◽  
Bimolecular Collisions ◽  
Alkali Chlorides ◽  
Principal Chain ◽  
Oxygen Reaction

On the basis of the theory discussed in the preceding parts of this series, a method has been devised for determining the temperature coefficient and hence the activation energy of the process responsible for starting the chains in the thermal reaction between hydrogen and oxygen. The results are consistent with the view that the production of hydrogen atoms (in bimolecular collisions between hydrogen and other molecules present) is the principal chain initiating reaction at temperatures above 560° C in vessels coated with alkali chlorides.

Seismicity of the Middle America arc-trench system near Managua, Nicaragua

1974 ◽  
Vol 64 (4) ◽  
pp. 1033-1048 ◽  
Author(s):  
James W. Dewey ◽  
S. T. Algermissen
Keyword(s):  
Surface Expression ◽  
Benioff Zone ◽  
Hypocenter Determination ◽  
Joint Hypocenter Determination ◽  
Volcanic Chain ◽  
Middle America ◽  
Master Event ◽  
Shallow Focus ◽  
Principal Chain ◽  
East West

Abstract Hypocenters of earthquakes occurring during the period 1950 through 1972 in the Middle America arc-trench system near Managua, Nicaragua, have been relocated by the method of joint hypocenter determination (JHD) or the master event method with the Managua earthquake of December 23, 1972 as the calibration event. The relocated hypocenters show a considerably narrower Benioff zone than previous hypocenters of the same earthquakes and clearly separate shallow-focus volcanic terrane earthquakes of the type which struck Managua from the Benioff zone earthquakes. The shallow-focus volcanic terrane earthquakes are probably caused by tectonic conditions associated with the formation of the Nicaraguan depression or the principal chain of Quaternary volcanoes. The Managua earthquake of December 23, 1972 may have occurred as a consequence of slippage along a transform fault zone which connects offset segments of the chain of Quaternary volcanoes; the volcanic chain is then taken to be the surface expression of a secondary spreading zone which lies above the Benioff zone of the Middle America arc-trench system. Alternatively, the recent Managua earthquake may have occurred as a consequence of regional east-west tension in the Nicaraguan depression.

On the chemistry of iodonyl radicals. The oxidation of iodobenzene by t-butyl hypochlorite

1968 ◽  
Vol 46 (22) ◽  
pp. 3537-3544 ◽  
Author(s):  
Dennis D. Tanner ◽  
Geoffrey C. Gidley
Keyword(s):  
Free Radical ◽  
Molecular Oxygen ◽  
Chlorinated Hydrocarbons ◽  
Chain Mechanism ◽  
Radical Chain ◽  
Thermally Induced ◽  
Chain Reactions ◽  
Hydrocarbon Substrates ◽  
Principal Chain ◽  
Sole Product

The reaction of iodobenzene with t-butyl hypochlorite proceeds by a free radical chain mechanism, forming as the sole product iodobenzene t-butoxy chloride (IBBC). The photoinduced or thermally induced reactions of IBBC with hydrocarbon substrates yield chlorinated hydrocarbons by a radical chain halogenation sequence involving t-butoxyiodonyl benzene as the principal chain-carrying species. The photolysis or thermolysis of IBBC in the absence of molecular oxygen yields products resulting from a variety of free radical chain reactions, while thermolysis in the presence of oxygen yields only iodobenzene and t-butyl hypochlorite.

Synthesis of new polymers with benzimidazoline units in the principal chain

1964 ◽  
Vol 6 (8) ◽  
pp. 1657-1660
Author(s):  
N.A. Adrova ◽  
A.M. Dubnova ◽  
M.M. Koton
Keyword(s):  
Principal Chain

scholarly journals Synthesis of Resins Using Epoxies and Humins as Building Blocks: A Mechanistic Study Based on in-situ FT-IR and NMR Spectroscopies

2019 ◽  
Author(s):  
Xavier Montané ◽  
Roxana Dinu ◽  
Alice Mija
Keyword(s):  
Nmr Spectroscopy ◽  
Chemical Conversion ◽  
Building Blocks ◽  
Added Value ◽  
Mechanistic Study ◽  
Ft Ir ◽  
Conversion Technologies ◽  
Principal Chain ◽  
Ft Ir Spectroscopy

The combination of eco-respectful epoxy compounds with the humins, a by-product of biomass chemical conversion technologies, allow the obtention of materials with high added value. In this work, we propose the chemical connection study of humins with two aliphatic diepoxides through the copolymerization reactions to synthesize sustainable bio-based thermosets. The mechanism insights for the crosslinking between the epoxides and humins was proposed considering the different functionalities of the humins structure. FT-IR spectroscopy, 1 D and 2 D NMR spectroscopy techniques were used to build the proposed mechanism. By these techniques, the principal chain connections and the reactivity of all the components were highlighted in the synthesized networks.

Sign in / Sign up

Export Citation Format

Share Document