About: Mole fraction is a(n) research topic. Over the lifetime, 9988 publication(s) have been published within this topic receiving 199311 citation(s). The topic is also known as: amount fraction & molar fraction.
01 Jan 1965-Aiche Journal
Abstract: A simple technique is described for calculating the adsorption equilibria for components in a gaseous mixture, using only data for the pure-component adsorption equilibria at the same temperature and on the same adsorbent. The proposed technique is based on the concept of an ideal adsorbed solution and, using classical surface thermodynamics, an expression analogous to Raoult's law is obtained. The essential idea of the calculation lies in the recognition that in an ideal solution the partial pressure of an adsorbed component is given by the product of its mole fraction in the adsorbed phase and the pressure which it would exert as a pure adsorbed component at the same temperature and spreading pressure as those of the mixture. Predicted isotherms give excellent agreement with experimental data for methane-ethane and ethylene-carbon dioxide on activated carbon and for carbon monoxide-oxygen and propane-propylene on silica gel. The simplicity of the calculation, which requires no data for the mixture, makes it especially useful for engineering applications.
01 Jul 2004-Journal of the American Chemical Society
TL;DR: It is shown that the conductivity and viscosity of these liquids is controlled by ion mobility and the availability of voids of suitable dimensions, and this is consistent with the fluidity of other ionic liquids and molten salts.
Abstract: Deep Eutectic Solvents (DES) can be formed between a variety of quaternary ammonium salts and carboxylic acids. The physical properties are significantly affected by the structure of the carboxylic acid but the phase behavior of the mixtures can be simply modeled by taking account of the mole fraction of carboxylic acid in the mixture. The physical properties such as viscosity, conductivity, and surface tension of these DES are similar to ambient temperature ionic liquids and insight into the cause of these properties is gained using hole-theory. It is shown that the conductivity and viscosity of these liquids is controlled by ion mobility and the availability of voids of suitable dimensions, and this is consistent with the fluidity of other ionic liquids and molten salts. The DES are also shown to be good solvents for metal oxides, which could have potential application for metal extraction.
01 Jan 2000-Pure and Applied Chemistry
Abstract: We report here the first systematic study of the effect of impurities and additives (e.g., water, chloride, and cosolvents) on the physical properties of room-temperature ionic liquids. Remarkably, it was discovered that the viscosity of mixtures was dependent mainly on the mole fraction of added molecular solvents and only to a lesser extent upon their iden- tity, allowing viscosity changes during the course of a reaction to be entirely predictable. While the addition of such molecular solvents decreases the viscosity and density, chloride impurities, arising from the preparation of the ionic liquids, increase viscosity dramatically. The commonly used methods of preparation were validated with respect to chloride impurity.
01 Nov 1993-Journal of the American Chemical Society
Abstract: This paper reports a study of the adsorption of four proteins-fibrinogen, lysozyme, pyruvate kinase, and RNAse A-to self-assembled monolayers (SAMs) on gold. The SAMs examined were derived from thiols of the structure HS(CH 2 ) 10 R, where R was CH 3 , CH 2 OH, and oligo(ethylene oxide). Monolayers that contained a sufficiently large mole fraction of alkanethiolate groups terminated in oligo(ethylene oxide) chains resisted the kinetically irreversible, nonspecific adsorption of all four proteins. Longer chains of oligo(ethylene oxide) were resistant at lower mole fractions in the monolayer. Resistance to the adsorption of proteins increased with the length of the oligo(ethylene oxide) chain: the smallest mole fraction of chains that prevented adsorption was proportional to n -0.4 , where n represents the number of ethylene oxide units per chain
05 Nov 1949-Nature
TL;DR: From a comparison of vapour pressures and viscosities of solutions, it is deduced that in many cases the following equation yields closer agreement with experimental results: where d is a characteristic constant of the system.
Abstract: ARRHENIUS1 proposed the following expression for the viscosity of a solution : where ηs is the viscosity of the solution ; N1 and η1 are the mole fraction and the viscosity of component 1 ; N2 and η2 the mole fraction and the viscosity of component 2. However, both positive and negative deviations from this equation are found to occur. From a comparison of vapour pressures and viscosities of solutions, we deduced that in many cases the following equation yields closer agreement with experimental results : where d is a characteristic constant of the system. The accompanying graph shows curves calculated according to equations 1 and 2 (with d = -0·0224) for the system trans-decalin—cis-decalin. The points on the graph represent the experimental results of Bird and Daly2.