Potentiometric studies on solubilisation in non-ionic micellar solutions. Part II. Solubilisation of benzoic acid and the hydroxybenzoic acids and location of the solubilisates

1967 ◽  
pp. 561 ◽  
Author(s):  
M. Donbrow ◽  
P. Molyneux ◽  
C. T. Rhodes
Keyword(s):  
Benzoic Acid ◽  
Potentiometric Studies ◽  
Micellar Solutions ◽  
Hydroxybenzoic Acids

COMPARISON OF THE REACTIVITY OF NANOSIZED ZERO-VALENT IRON (nZVI) PARTICLES PRODUCED BY BOROHYDRIDE AND DITHIONITE REDUCTION OF IRON SALTS

NANO ◽  
2008 ◽  
Vol 03 (05) ◽  
pp. 341-349 ◽  
Author(s):  
QUAN SUN ◽  
ANDREW J. FEITZ ◽  
JING GUAN ◽  
T. DAVID WAITE
Keyword(s):  
Benzoic Acid ◽  
Hydrogen Gas ◽  
Zero Valent Iron ◽  
No Production ◽  
High Concentration ◽  
Acid Generation ◽  
Reduction Of Iron ◽  
Hydroxybenzoic Acids ◽  
Tce Degradation ◽  
Primary Oxidation

Dithionite can be used to reduce Fe (II) and produce nanoscale zero-valent iron (nZVI) under conditions of high pH and in the absence of oxygen. The nZVI is coprecipitated with a sulfite hydrate in a thin platelet. The nanoparticles formed are not pure iron but this feature does not appear to affect their degradation performance under air or N 2 gas conditions. The efficiency of trichloroethylene (TCE) degradation, when one is employing nanoparticles manufactured using dithionite ( nZVI S 2 O 4), is similar to if not slightly better than that of the more conventional borohydride procedure ( nZVI BH 4). The other advantages of the dithionite method are that (i) it uses a less expensive and widely available reducing agent, and (ii) there is no production of potentially explosive hydrogen gas. Oxidation of benzoic acid using the nZVI S 2 O 4 particles results in different byproducts than those produced when nZVI BH4 particles are used. The low oxidant yield based on hydroxybenzoic acid generation is offset by the production of higher concentrations of phenol. The high concentration of phenol compared to hydroxybenzoic acids suggests that OH • addition is not the primary oxidation pathway when one is using the nZVI S 2 O 4 particles. It is proposed that sulfate radicals ([Formula: see text]) are produced as a result of hydroxyl radical attack on the sulfite matrix surrounding the nZVI S 2 O 4 particles, with these radicals oxidizing benzoic acid via electron transfer reactions rather than addition reactions.

The reaiation chemistry of aqueous solutions of [14C]Benzoic and [14C}Salicylic Acids

1958 ◽  
Vol 11 (2) ◽  
pp. 154 ◽  
Author(s):  
AM Downes
Keyword(s):  
Salicylic Acid ◽  
Ionizing Radiation ◽  
Benzoic Acid ◽  
Aqueous Solutions ◽  
Radioactive Tracer ◽  
Alkaline Solutions ◽  
X Rays ◽  
Tracer Techniques ◽  
Hydroxybenzoic Acids ◽  
G Value

Radioactive tracer techniques have been used to study the effect of ionizing radiation (60Co γ-radiation and 45 kV X-rays) on [14C]benzoic acid (both carboxyl- and uniformly-labelled) and on [carboxy-14C]salicylic acid in aerated aqueous solutions. �� The production of o-, m-, and p-hydroxybenzoic acids from benzoic acid (Loebl, Stein, and Weiss 1951) has been cord3rmed. The approximate initial G values for these products were : ortho, 0.74 ; meta, 0.42 ; para, 0.33. The ratio o : m : p was thus approximately 9 : 5 : 4 whereas Loebl, Stein, and Weiss found the corresponding ratio to be 5 : 2 : 10. Benzoic acid and sodium benzoate were also decarboxylated [G(CO2) : 0.73 � 0.03]. The extent of decarboxylation was independent of the initial concentration of benzoic acid in the range studied (0.5-7.0 X 10-3 M). The total reaction of the benzoic acid corresponded to a G value of approximately 2.6. Very little, if any, diphenyl was produced. The main non-volatile products from salicylic acid were 2,3- and 2,5-dihydroxy- benzoic acids which were obtained in the ratio 2,5 : 2,3 :: 1 : 1.6. The 2,4- and 2,6- isomers were not detected. Salicylic acid was also decarboxylated, G(CO2) being 1 53 � 0.07 in alkaline solutions. The above results are compared with other results relating to free-radical reactions. The possible use of the decarboxylation of sodium [carboxy-14C]benzoate as a sensitive dosimeter for ionizing radiation is suggested.

scholarly journals Hydroxybenzoic Acids — A Study of Their Electronic Spectra, Structure and Reactivity

1982 ◽  
Vol 37 (10) ◽  
pp. 1185-1192 ◽  
Author(s):  
K. P. Krishnan Namboodiri ◽  
S. Viswanathan ◽  
V. C. lyothi Bhasu
Keyword(s):  
Benzoic Acid ◽  
Electronic Spectra ◽  
Valence State ◽  
Valence Electron ◽  
Chemical Reactivity ◽  
Structural Parameters ◽  
Aqueous Media ◽  
Ionization Potentials ◽  
Hydroxybenzoic Acids ◽  
Ci Calculations

The three isomeric hydroxybenzoic acids were subjected to all-valence-electron CNDO/2 calculations. The σ-core charges from these calculations and subsequently revised valence-state ionization potentials and one-centre two-electron integrals were used in Pariser-Parr-Pople (PPP) CI calculations for the title compounds following the Nishimoto-Forster scheme to explain their electronic spectra. The spectra were all recorded in aqueous media. The results from the CNDO/2 calculations were used to obtain useful electronic structural parameters and to study the chemical reactivity of these molecules. All the results were compared with the basic compounds, namely phenol and benzoic acid.

REACTION OF ANHYDROSEPEDONIN WITH ALKALI SYNTHESIS OF A DEGRADATION PRODUCT AND SOME RELATED DIMETHYLHYDROXYBENZOIC ACIDS

1964 ◽  
Vol 42 (1) ◽  
pp. 63-68 ◽  
Author(s):  
P. V. Divekar ◽  
L. C. Vining
Keyword(s):  
Benzoic Acid ◽  
Degradation Product ◽  
Hydroxybenzoic Acid ◽  
Hydroxybenzoic Acids

Two products have been isolated from the reaction of anhydrosepedonin with alkali and identified as 3-hydroxy-5-methyl benzoic acid and 3,4-dimethyl-5-hydroxybenzoic acid. The structure of the latter compound was established by unambiguous synthesis. In the course of this work the remaining o- and m-hydroxybenzoic acids derived from o-xylene were also prepared.

TEM characterization of proton-exchanged LiNbO3 optical waveguides

1986 ◽  
Vol 44 ◽  
pp. 480-481
Author(s):  
W. E. Lee
Keyword(s):  
Refractive Index ◽  
Benzoic Acid ◽  
Optical Waveguides ◽  
Total Internal Reflection ◽  
Index Of Refraction ◽  
Optical Measurements ◽  
Lithium Ions ◽  
Wide Channel ◽  
Tem Characterization

An optical waveguide consists of a several-micron wide channel with a slightly different index of refraction than the host substrate; light can be trapped in the channel by total internal reflection.Optical waveguides can be formed from single-crystal LiNbO3 using the proton exhange technique. In this technique, polished specimens are masked with polycrystal1ine chromium in such a way as to leave 3-13 μm wide channels. These are held in benzoic acid at 249°C for 5 minutes allowing protons to exchange for lithium ions within the channels causing an increase in the refractive index of the channel and creating the waveguide. Unfortunately, optical measurements often reveal a loss in waveguiding ability up to several weeks after exchange.

Sign in / Sign up

Export Citation Format

Share Document