Limiting activity coefficients in dilute solutions of nonelectrolytes. II. Determination for polar–nonpolar and polar–polar binary mixtures, and the application of some solubility-parameter treatments

1986 ◽  
Vol 64 (1) ◽  
pp. 198-203 ◽  
Author(s):  
Shapour Afrashtehfar ◽  
Genille C. B. Cave
Keyword(s):  
Binary Mixture ◽  
Activity Coefficients ◽  
Vapor Phase ◽  
Solubility Parameter ◽  
Chromatographic Analysis ◽  
Dipole Interaction ◽  
The Other ◽  
Binary Solutions ◽  
Polar Components ◽  
Induced Dipole

Activity coefficients were determined at 293.15 K for the more dilute component in 24 binary solutions of nonelectrolytes, by gas-chromatographic analysis of the equilibrium vapor phase. One component of the binary mixture was either nitromethane, nitroethane, 1-nitropropane, 2-nitropropane, ethanenitrile, propanenitrile, ethyl ethanoate, or butyl ethanoate; and the other component was either heptane, 1-heptene, or 1,6-heptadiene.From the limiting activity coefficients of these components, some factors that affected their magnitude were identified. The values were also used to test the modifications of Prausnitz, Blanks, and Weimer, of Helpinstill and Van Winkle, and of Keller, Karger, and Snyder to the Scatchard–Hildebrand equation modified to accommodate polar components. In addition, the degree of constancy of the ratio of the dipole – induced dipole interaction parameter for a series of solutes in one solvent to that in another was considered.

Limiting activity coefficients in dilute solutions of nonelectrolytes. I.Determination for polar–nonpolar binary mixtures by a novel apparatus, and a solubility-parameter treatment of results

1982 ◽  
Vol 60 (21) ◽  
pp. 2697-2706 ◽  
Author(s):  
Etela Milanová ◽  
Genille C. B. Cave
Keyword(s):  
Binary Mixtures ◽  
Activity Coefficients ◽  
Solubility Parameter ◽  
Butyl Acetate ◽  
Dipole Interaction ◽  
Polar Compounds ◽  
Polar Component ◽  
Nonpolar Solvents ◽  
Induced Dipole ◽  
Polar Solutes

The activity coefficients of several solutes in dilute binary solutions of nonelectrolytes were determined at 20 °C from vapour–liquid equilibria in a novel static equilibration apparatus, by gas-chromatographic analysis of the equilibrium vapor phase. The solutes were nitromethane, nitroethane, 1-nitropropane, 2-nitropropane, acetonitrile, propionitrile, ethyl acetate, and n-butyl acetate in n-heptane and in benzene as solvents, and also carbon tetrachloride as solute in each of the above-listed polar compounds as the solvent.The modifications by Weimer and Prausnitz and by Blanks and Prausnitz to the Scatchard–Hildebrand equation in order to accommodate binary mixtures containing a polar component were tested by using the values found in the present work for the limiting activity coefficients of these solutes. In addition, it was found that the ratio of the dipole – induced dipole interaction parameter for polar solutes in the two nonpolar solvents was nearly constant.Three methods for evaluating the dispersion contribution to the solubility parameter of a polar compound were considered.

scholarly journals Computational Study of the Electron Spectra of Vapor-Phase Indole and Four Azaindoles

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1947
Author(s):  
Delano P. Chong
Keyword(s):  
Density Functional Theory ◽  
Vapor Phase ◽  
Density Functional ◽  
Computational Study ◽  
Geometry Optimization ◽  
The Other ◽  
Functional Theory ◽  
Electron Spectra

After geometry optimization, the electron spectra of indole and four azaindoles are calculated by density functional theory. Available experimental photoemission and excitation data for indole and 7-azaindole are used to compare with the theoretical values. The results for the other azaindoles are presented as predictions to help the interpretation of experimental spectra when they become available.

scholarly journals Perception of Aqueous Ethanol Binary Mixtures Containing Alcohol-Relevant Taste and Chemesthetic Stimuli

Beverages ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 23
Author(s):  
Margaret Thibodeau ◽  
Gary Pickering
Keyword(s):  
Binary Mixture ◽  
Binary Mixtures ◽  
Aqueous Ethanol ◽  
Ethanol Concentration ◽  
Alcoholic Beverages ◽  
Complex Stimulus ◽  
Aluminium Sulphate ◽  
Binary Solutions ◽  
Wide Range ◽  
Thermal Taste

Ethanol is a complex stimulus that elicits multiple gustatory and chemesthetic sensations. Alcoholic beverages also contain other tastants that impact flavour. Here, we sought to characterize the binary interactions between ethanol and four stimuli representing the dominant orosensations elicited in alcoholic beverages: fructose (sweet), quinine (bitter), tartaric acid (sour) and aluminium sulphate (astringent). Female participants were screened for thermal taste status to determine whether the heightened orosensory responsiveness of thermal tasters (n = 21–22) compared to thermal non-tasters (n = 13–15) extends to these binary mixtures. Participants rated the intensity of five orosensations in binary solutions of ethanol (5%, 13%, 23%) and a tastant (low, medium, high). For each tastant, 3-way ANOVAs determined which factors impacted orosensory ratings. Burning/tingling increased as ethanol concentration increased in all four binary mixture types and was not impacted by the concentration of other stimuli. In contrast, bitterness increased with ethanol concentration, and decreased with increasing fructose concentration. Sourness tended to be reduced as ethanol concentration increased, although astringency intensity decreased with increasing concentration of fructose. Overall, thermal tasters tended to be more responsive than thermal non-tasters. These results provide insights into how the taste and chemesthetic profiles of alcoholic beverages across a wide range of ethanol concentrations can be manipulated by changing their composition.

Basalflecke und Fleckenlosigkeit in Mohnblüten: Eine chemogenetische Charakterisierung / Basal Blotches and Blotchlessness of Poppy Flowers: A Chemogenetic Characterization

1986 ◽  
Vol 41 (1-2) ◽  
pp. 158-163 ◽  
Author(s):  
H. Böhm
Keyword(s):  
Chromatographic Analysis ◽  
Interspecific Cross ◽  
Basic Number ◽  
The Other ◽  
Close Relative ◽  
Papaver Bracteatum

Abstract While Papaver bracteatum and P. pseudo-orientale exhibit large basal blotches in red flowers, these marks are absent in the flowers of their close relative P. orientale. Crossing of the latter species with the former ones surprisingly resulted in hybrids showing blotchlessness. In contrast, the hybrid derived from the interspecific cross P. sommniferum x P. orientale forms relatively small but distinct basal blotches. The first parent has marked, white flowers and another basic number of the genome (x = 11) than P. orientale and its relatives have (x = 7). Chromatographic analysis confirm ed that pelargonidin and cyanidin are the anthocyanidins of poppy flowers. Basal blotches differ from the other parts of petals since they exclusively contain cyanidin glycosides. If they are absent, pelargonidin glycosides homogeneously colour the petals. It is concluded that in blotchless flowers of P. orientale and its hybrids the gene responsible for the 3′-hydroxylation of C15 molecules is repressed. This situation is obviously restricted to the basal areas of petals.

HYDROGEN STORAGE ON NANOFULLERENE CAGES

NANO ◽  
2009 ◽  
Vol 04 (05) ◽  
pp. 253-263 ◽  
Author(s):  
NATARAJAN SATHIYAMOORTHY VENKATARAMANAN ◽  
HIROSHI MIZUSEKI ◽  
YOSHIYUKI KAWAZOE
Keyword(s):  
Hydrogen Storage ◽  
Dipole Interaction ◽  
Binding Energies ◽  
Reversible System ◽  
Storage Medium ◽  
Transition Elements ◽  
Practical Applications ◽  
Alkali Earth ◽  
Induced Dipole ◽  
A Charge

In this paper, we discuss and compare various nanocage materials proposed theoretically as storage medium for hydrogen. Doping of transition elements leads to clustering which reduces the gravimetric density of hydrogen, while doping of alkali and alkali-earth metals on the nanocage materials, such as carborides, boronitride, and boron cages, were stabilized by the charger transfer from the dopant to the nanocage. Further, the alkali or alkali-earth elements exist with a charge, which are found to be responsible for the higher uptake of hydrogen, through a dipole–dipole and change-induced dipole interaction. The binding energies of hydrogen on these systems were found to be in the range of 0.1 eV to 0.2 eV, which are ideal for the practical applications in a reversible system.

Relation of the metabolism of sulfobromophthalein sodium to its blood clearance in the rat

1959 ◽  
Vol 197 (2) ◽  
pp. 292-296 ◽  
Author(s):  
John S. Krebs
Keyword(s):  
Chromatographic Analysis ◽  
The Other ◽  
Blood Clearance ◽  
Chain Sequence ◽  
A Chain ◽  
Derivatives Of

Chromatographic analysis of BSP (sodium phenoltetrabromphthalein disulfonate) excreted into the bile of the rat showed that the BSP had undergone transformation into similarly colored but chemically different compounds. Injection of purified samples of these derived compounds into the rat showed that the compounds were less effectively removed from plasma than BSP but were excreted into bile at almost the same rate as when pure BSP was injected. Chromatographic analysis of bile following injection of the isolated bile-type derivatives of BSP showed that the derivatives were formed, one from the other, in a chain sequence, starting with BSP. Chromatographic analysis of the blood following injection of BSP showed that bile-type derivatives of BSP appeared in the blood and became progressively more predominant with increasing time after injection of the BSP.

scholarly journals Experimental quantification of contact freezing in an electrodynamic balance

2013 ◽  
Vol 6 (9) ◽  
pp. 2373-2382 ◽  
Author(s):  
N. Hoffmann ◽  
A. Kiselev ◽  
D. Rzesanke ◽  
D. Duft ◽  
T. Leisner
Keyword(s):  
Average Rate ◽  
Aerosol Particles ◽  
Dipole Interaction ◽  
Ice Nucleation ◽  
Particle Collision ◽  
Charged Droplet ◽  
Particle Collisions ◽  
Ice Nuclei ◽  
Induced Dipole ◽  
Levitated Droplet

Abstract. Heterogeneous nucleation of ice in a supercooled water droplet induced by external contact with a dry aerosol particle has long been known to be more effective than freezing induced by the same nucleus immersed in the droplet. However, the experimental quantification of contact freezing is challenging. Here we report an experimental method to determine the temperature-dependent ice nucleation probability of size-selected aerosol particles. The method is based on the suspension of supercooled charged water droplets in a laminar flow of air containing aerosol particles as contact freezing nuclei. The rate of droplet–particle collisions is calculated numerically with account for Coulomb attraction, drag force and induced dipole interaction between charged droplet and aerosol particles. The calculation is verified by direct counting of aerosol particles collected by a levitated droplet. By repeating the experiment on individual droplets for a sufficient number of times, we are able to reproduce the statistical freezing behavior of a large ensemble of supercooled droplets and measure the average rate of freezing events. The freezing rate is equal to the product of the droplet–particle collision rate and the probability of freezing on a single contact, the latter being a function of temperature, size and composition of the contact ice nuclei. Based on these observations, we show that for the types of particles investigated so far, contact freezing is the dominating freezing mechanism on the timescale of our experiment.

Retardation in non-dispersive interactions between molecules

1966 ◽  
Vol 295 (1443) ◽  
pp. 476-489 ◽  
Keyword(s):  
Quantum Electrodynamics ◽  
Exchange Interactions ◽  
Dipole Interaction ◽  
Second Order ◽  
The Other ◽  
Spin Orbit ◽  
Wave Zone ◽  
Expectation Value ◽  
Near Zone ◽  
The Matrix

The second order T matrix corresponding to the interaction between two molecules is calculated by quantum electrodynamics. In the near zone the matrix reduces to the expectation value of the Breit Hamiltonian for the two-centre problem. In the wave zone a retarded Briet operator is found for exchange interactions. A reduction to the Pauli limit is made. The interactions are discussed severally for the spin-spin, (spin-dipole)-(spin-dipole), spin-orbit and dipole-(spin-dipole) cases. At large separations the T matrix is complex and the imaginary parts, previously given for the dipole-dipole interaction, are found for the other cases.

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