ChemInform Abstract: Gas-Phase Association Reactions of Trimethylsilylium (Me3Si+) with Organic Bases

ChemInform ◽  
2010 ◽  
Vol 28 (46) ◽  
pp. no-no
Author(s):  
J. A. STONE
Keyword(s):  
Gas Phase ◽  
Organic Bases

Structural effects on the iodine cation basicity of organic bases in the gas phase

1989 ◽  
Vol 111 (24) ◽  
pp. 8960-8961 ◽  
Author(s):  
Jose Luis M. Abboud ◽  
Rafael Notario ◽  
Lucia Santos ◽  
Carmen Lopez-Mardomingo
Keyword(s):  
Gas Phase ◽  
Structural Effects ◽  
Organic Bases

Calculation of Acidity Constants of Protonated Weak Organic Bases by a New Method, III* Ethers

1979 ◽  
Vol 34 (4) ◽  
pp. 614-620 ◽  
Author(s):  
L. S. Levitt ◽  
B. W. Levitt
Keyword(s):  
Gas Phase ◽  
New Method ◽  
Acidity Constants ◽  
Organic Bases ◽  
Good Agreement

Abstract It is shown in this paper that a consistent set of values of pKBH⁺ for 24 ethers, in good agreement with the few which have been obtained by other methods, can be calculated from a correlation of the HCl solubility in the ethers with ∑σI of the R groups, and also with the gas phase I.P.'s of the ethers. We find that in solution the order of basicity is ROH>R2O>H2O whereas in the gas phase it is R2O>ROH>H2O. Evidence for complete H+ transfer to R2O is deduced for most cases, but a H-bonding "basicity" occurs for the less basic ethers. A brief review of previously obtained pKBH⁺'s for some ethers, MeOH, and H2O is also presented.

Cytochemical analysis of mast cell granules after poly-dl-lysine action

1978 ◽  
Vol 36 (2) ◽  
pp. 278-279
Author(s):  
R. Courtoy ◽  
L.J. Simar ◽  
J. Christophe
Keyword(s):  
Mast Cell ◽  
Mast Cells ◽  
Chemical Compounds ◽  
Cellular Membrane ◽  
Thin Sections ◽  
Organic Bases ◽  
Ferric Thiocyanate ◽  
Cytochemical Analysis ◽  
Mast Cell Granule ◽  
Amine Liberation

Several chemical compounds induce amine liberation from mast cells but do not necessarily provoque the granule expulsion. For example, poly-dl-lysine induces modifications of the cellular membrane permeability which promotes ion exchange at the level of mast cell granules. Few of them are expulsed but the majority remains in the cytoplasm and appears less dense to the electrons. A cytochemical analysis has been performed to determine the composition of these granules after the polylysine action.We have previously reported that it was possible to demonstrate polyanions on epon thin sections using a cetylpyridinium ferric thiocyanate method. Organic bases are selectively stained with cobalt thiocyanate and the sulfhydryle groups are characterized with a silver methenamine reaction. These techniques permit to reveal the mast cell granule constituents, i.e. heparin, biogenic amines and basic proteins.

Residual Gas Reactions in the Electron Microscope: I. Qualitative Observations on the Water Gas Reaction

1968 ◽  
Vol 26 ◽  
pp. 292-293
Author(s):  
Richard E. Hartman ◽  
Roberta S. Hartman ◽  
Peter L. Ramos
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Gas Phase ◽  
Absolute Temperature ◽  
Residual Gas ◽  
Gas Reactions ◽  
Image Position ◽  
The Right ◽  
Water Gas ◽  
Thinning Rate

The action of water and the electron beam on organic specimens in the electron microscope results in the removal of oxidizable material (primarily hydrogen and carbon) by reactions similar to the water gas reaction .which has the form:The energy required to force the reaction to the right is supplied by the interaction of the electron beam with the specimen.The mass of water striking the specimen is given by:where u = gH2O/cm2 sec, PH2O = partial pressure of water in Torr, & T = absolute temperature of the gas phase. If it is assumed that mass is removed from the specimen by a reaction approximated by (1) and that the specimen is uniformly thinned by the reaction, then the thinning rate in A/ min iswhere x = thickness of the specimen in A, t = time in minutes, & E = efficiency (the fraction of the water striking the specimen which reacts with it).

Integration of Core-Edge Spectroscopy Methods for the Study of Polymers

1996 ◽  
Vol 54 ◽  
pp. 154-155
Author(s):  
E. G. Rightor
Keyword(s):  
Excited State ◽  
Polymer Blends ◽  
Gas Phase ◽  
Spatial Resolution ◽  
High Spatial Resolution ◽  
Electronic States ◽  
Core Electron ◽  
Bulk Solids ◽  
Development Application

Core edge spectroscopy methods are versatile tools for investigating a wide variety of materials. They can be used to probe the electronic states of materials in bulk solids, on surfaces, or in the gas phase. This family of methods involves promoting an inner shell (core) electron to an excited state and recording either the primary excitation or secondary decay of the excited state. The techniques are complimentary and have different strengths and limitations for studying challenging aspects of materials. The need to identify components in polymers or polymer blends at high spatial resolution has driven development, application, and integration of results from several of these methods.

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