80. The determination of “active” hydrogen

Braude, E. A.; Stern, E. S.

doi:10.1039/jr9460000404

Cited by 30 publications

(41 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Optical absorbances of the diluted solutions were measured by a Beckmann DU model G 2400 spectrophotometer at 380 nm. The molar extinction coefficient of pNA in water was taken to be 12 800 (15). Saturation at a given temperature was attained in all solvents within 7-10 days.…”

Section: Methodsmentioning

confidence: 99%

Thermodynamics of transfer of p-nitroaniline from water to alcohol + water mixtures at 25 °C and the structure of water in these media

Bose¹,

Kundu²

1977

Can. J. Chem.

View full text Add to dashboard Cite

Free energies (ΔGt0) and entropies (ΔSt0) of transfer at 25 °C of the nonelectrolyte p-nitroaniline from water to various alcohol + water mixtures have been determined from solubility measurements at seven temperatures from 10–40 °C. Increasing specific solute–solvent interactions have been proposed to interpret the nature of the ΔGt0-composition profiles and the enhanced structure of water in the water-rich mixed solvents has been correlated with maxima in the ΔSt0-composition profiles. The effectiveness of p-nitroaniline as a useful probe for studying solvent structure has been pointed out.

show abstract

Section: Methodsmentioning

confidence: 99%

Thermodynamics of transfer of p-nitroaniline from water to alcohol + water mixtures at 25 °C and the structure of water in these media

Bose¹,

Kundu²

1977

Can. J. Chem.

View full text Add to dashboard Cite

show abstract

“…In the spectroscopic analysis the value IS assumed to be lo6 for extended a-electron systems. A method of calculating the value of efheory from the molecular volume of the n-electron system was developed by Braude [28,29]. In Braude's method, the maximum theoretical extinction coefficient is calculated from of &theory .…”

Section: Microelectrode Determination Of the Aggregation Of Sunset Yementioning

confidence: 99%

“…The value of a, the probability of a photon being absorbed by a monomer, can be determined from [28,29] where cexP is the extinction coefficient, when Beer-Lambert law is obeyed, and sfheorY is the maximum theoretical extinction coefficient of an absorbing species, which for dye molecules is thought to be around 105-106 [28,29]. For the present aggregation model, it was assumed to be lo6 for dyes with extended a-electron systems by Pugh et al The assumption of the value of cfheorY is a potential weakness of the theory because of the sensitivity of a to its value.…”

Section: Spectroscopic Determination Of the Aggregation Of Sunset Yelmentioning

confidence: 99%

A new electrochemical method for the investigation of the aggregation of dyes in solution

et al. 1997

View full text Add to dashboard Cite

A new electrochemical technique is presented for the investigation of aggregation phenomena in solution over a wide range of solution conditions. Developed nominally for dyes, the method is, in principle, applicable to any electroactive compound. The method employs microelectrodes to measure the change in the diffusion limited current, with concentration, of the aggregating species of interest. At the onset of aggregation, the relationship between this limiting current and concentration deviates from linearity. This deviation, due to the slower rate of diffusion of aggregates, is related to the degree of association of the molecule, assuming a molecular weight distribution of aggregates and using an established relationship between the effective diffusion coefficient and molecular weight. The technique is contrasted with an existing spectroscopic method.

show abstract

“…The solid curve represents (-H o -C HC1 ) from the data of Braude and Stern. 46 where /?+(s) and R+(vs) are the empirical radius corrections specific to the non-aqueous solvent and to water, respectively. In this manner, Keopp, Wendt and Strehlow 50 calculated the values of AG° of the rubidium ion (less rigorously termed the free energies of transfer of Rb + from water to the solvent) for several non-aqueous media.…”

Section: Calculations Based On Modified Born Equationsmentioning

confidence: 99%