Vapor-phase Mixture Research Articles

Thermodynamic Study of the Electric Field Effect on Liquid-Vapor Mixture at Equilibrium: An Analysis on a Water-Ethanol Mixture.

In this paper, the effect of electric fields on phase equilibria through polarization is investigated. A relation is derived for the chemical potential of a system, where the electric field is localized over a liquid phase mixture in equilibrium with a vapor phase mixture. This relation is then applied to a water-ethanol mixture to explore the effect of polarization-based electric fields on the liquid phase composition. It is observed that the quadratic dependence on electric field strength produces little effect below field strengths of approx. 10 MV/m. However, above this field strength, the mole fraction of water in the liquid phase grows rapidly, increasing by a factor of 8 for a water vapor phase fraction of 0.2 and a field strength of 500 MV/m, which approaches the dielectric breakdown strength of water. Nonetheless, this field strength could be achievable with microfluidic experimental setups.

Conductivity of SbxSey films grown by CMBD from Sb and Se precursors for use in solar cells

Antimony selenide (Sb2Se3) has been developed as attractive, non-toxic and earth-abundant solar absorber candidate among the thin-film photovoltaic devices. The growth of SbxSey thin films, by atmospheric pressure chemical molecular beam deposition (CMBD) method, from separate Sb and Se precursors has been reported. The conductivity of the films was investigated as a function of the vapor phase mixture of Sb and Se. By the precise control of the Sb/Se ratio we succeeded in obtaining stoichiometric Sb2Se3 films. It is also found out that we can control the conductivity by deliberately introducing the deviation from the stoichiometry. The conductivity was varied in the wide range of 10−5 ÷ 102 (Ohm × cm)−1 and samples had p- and n-type conductivity depending on Sb/Se ratio. The obtained results were explained by the formation of intrinsic point defects.

Cocrystallization from ibuprofen–nicotinamide vapor phase mixture in the absence and presence of seeds

Cocrystal formation may affect physicochemical properties of drugs. This work introduces a vapor crystallization method for preparing ibuprofen–nicotinamide cocrystals in the absence and presence of seeds. The vapor came from the sublimation of ibuprofen and nicotinamide crystal or from the sublimation of pure ibuprofen–nicotinamide cocrystals under the controlled temperature. A presumable mechanism of the cocrystallization from vapor phase was proposed.

Spray, atomization and combustion characteristics of oxygenated fuels in a constant volume bomb: A review

Biofuels have extensive available resources and have an immense potential as promising alternative fuels for automobile. The application advantages of biofuels are mainly reflected as particulate matter (PM) reduction, carbon neutral, greenhouse gases reduction, waste utilization, energy and economic security, and fuel pluralism. Based on the understanding of molecular structure effects of biofuels on soot formation and particles morphology, the effects of alcohols, ethers, esters and biodiesel on spray and combustion process in constant volume bomb in recent years are retrospectively analyzed in this paper. For the mixture, macromolecular ester fuels and polyoxymethylene dimethyl ether (PODE) are conducive to the improvement of liquid spray, while biodiesel, small molecules, dimethyl ether (DME) and alcohols are reversed. Alcohols are advantageous to the extension of mixing time and the increasing of vapor-phase mixture. Through the influence integrated assessment, alcohols show the best performance on the spray, atomization and combustion, while biodiesels show the worst. But in terms of combustion, PODE is the best choice without considering spray and atomization. For binary alternative-diesel fuel blends, methanol or butanol is the best additive based on synthetically considerations on spray, atomization and combustion. To meet the requirements of the fuel application of diesel engine, ternary fuel or even quaternary fuel have been proposed and explored. This review can help to form a systematic understanding on fuel recombining and obtain the guide of clean and efficient fuel formulation for diesel engine. • Spray and combustion in constant volume bomb fueled with oxygenated fuels are reviewed. • Spray and combustion of different oxygen functional group fuels are analyzed. • Spray and combustion of different carbon chain length fuels are analyzed. • Spray and combustion of biodiesel from different sources are analyzed. • Spray and combustion of different functional group position esters are analyzed.

Vapor-Phase Growth and Structural Characterization of Single Crystals of Magnesium Doped Two-Dimensional Fullerene Polymer Mg2C60

Single crystals of magnesium doped fullerene polymer Mg2C60 can be directly grown via a binary vapor-phase mixture of Mg and C60, in sealed glass tubes at elevated temperatures. This is the first single crystal, in metal-doped two-dimensional fullerene polymers, which enables precise X-ray structural refinement. The Mg2C60 crystallizes in a monoclinic space group, I2/m, with lattice parameters of a = 9.324(2) A, b = 9.041(2) A, c = 14.817(3) A, and β = 91.699(10)°. A Mg atom is located at each tetrahedral fullerene ball interstice, where the shortest Mg–C distance is 2.341(2) A, suggesting that the Mg cation is in van der Waals contact with carbon p orbitals. The precise structure of the two-dimensional fullerene polymer network is characterized by comparison with structural data reported previously on powder samples.

Theory of Multicomponent Gas/Oil Displacements

Chromatographic separations that occur during two-phase flow in a porous medium are analyzed for one-dimensional, dispersion-free displacement of a liquid hydrocarbon mixture (oil) by a vapor phase mixture (gas). The authors show that displacement behavior is controlled by a set of key equilibrium the lines, all of which are determined by geometric constructions in composition space: two of the key tie lines are those that extend through the initial oil and injection gas compositions, and the remainder are tie lines that are located at intersections of ruled surfaces of tie lines. Very efficient displacement of oil by gas results if any of the key tie lines is a critical tie line. That high displacement efficiency is the basis of so-called miscible gas injection processes for enhanced oil recovery.

Vibrational and electronic spectra of matrix-isolated pentacene cations and anions

Pentacene cations and anions have been formed by electron bombardment of a vapor phase mixture of pentacene, Ar and CCl 4 and trapped in an argon matrix. The electronic and infrared spectra of both ions have been recorded. Increasing concentrations of CCl 4 resulted in the eventual disappearance of the anion spectrum. The intensity distributions of the IR spectra of the ions are similar but differ markedly from the distribution of neutral pentacene. The ion intensities resemble the distribution of the so-called interstellar ‘unidentified infrared’ bands. The visible bands of neutral, cationic and anionic pentacene are compared with the diffuse interstellar bands.

Visible and infrared spectra of matrix-isolated perylene cations

Perylene radical cations have been produced via low-energy electron impact of a vapor phase mixture of perylene, argon and carbon tetrachloride. The cations have been trapped and stabilized in an argon matrix at 12K in sufficient quantities to observe their infrared (and visible) absorption spectra. A strong green (534 nm) electronic absorption band, previously produced by γ-irradiation of perylene in an s-butylchloride matrix (77 K), has been ascribed to the perylene cation. A positive correlation has been found between this band and the newly observed infrared bands at 1128, 1318, 1346, 1349, and 1551 cm −1. The integrated intensities of these and other bands, assigned tothe perylene cation, have been measured and are discussed in light of the recent suggestion that polycyclic aromatic hydrocarbons are the carriers of the unidentified infrared emission bands observed from interstellar space.

Infrared spectrum of matrix-isolated naphthalene radical cation

Radical cations of naphthalene (N) have been formed by electron bombardment of a vapor-phase mixture of naphthalene, carbon tetrachloride, and argon and trapped in a matrix (Ar) at 12 K. Infrared spectral scans of this matrix compared to ones containing neutral N alone or electron-bombarded CCl 4 reveal new vibrational bands at 1525, 1519, 1401, 1218, 1215, 1023, and 1016 cm -1 . These bands are attributable to the N cation by their positive correlation with the known N cation 2 B 3g (D 2 )←X 2 A u (D 0 ) band system at 675 nm

Computer-assisted infrared identification of vapor-phase mixture components

The IRBASE/MIXIR system was originally tested on interpretation of infrared spectra of condensed-phase mixtures. The system has now been adapted to allow interpretation of vapor-phase mixture spectra. The dynamic interpretation capabilities of the system have been expanded to allow runtime manipulation of complete peak lists, allowing generation of the optimum spectral description for the interpretation at hand. The modifications to the system are described, along with the results of testing on actual mixtures of varying complexity.

The lenoir gas engine

Biofuels have extensive available resources and have an immense potential as promising alternative fuels for automobile. The application advantages of biofuels are mainly reflected as particulate matter (PM) reduction, carbon neutral, greenhouse gases reduction, waste utilization, energy and economic security, and fuel pluralism. Based on the understanding of molecular structure effects of biofuels on soot formation and particles morphology, the effects of alcohols, ethers, esters and biodiesel on spray and combustion process in constant volume bomb in recent years are retrospectively analyzed in this paper. For the mixture, macromolecular ester fuels and polyoxymethylene dimethyl ether (PODE) are conducive to the improvement of liquid spray, while biodiesel, small molecules, dimethyl ether (DME) and alcohols are reversed. Alcohols are advantageous to the extension of mixing time and the increasing of vapor-phase mixture. Through the influence integrated assessment, alcohols show the best performance on the spray, atomization and combustion, while biodiesels show the worst. But in terms of combustion, PODE is the best choice without considering spray and atomization. For binary alternative-diesel fuel blends, methanol or butanol is the best additive based on synthetically considerations on spray, atomization and combustion. To meet the requirements of the fuel application of diesel engine, ternary fuel or even quaternary fuel have been proposed and explored. This review can help to form a systematic understanding on fuel recombining and obtain the guide of clean and efficient fuel formulation for diesel engine.