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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

The Orientation of molecules in surfaces, surface energy, adsorption, and surface catalysis. V. The adhesional work between organic liquids and water. Vaporization in steps as related to surface formation ... /

Roberts, Lathrop Emerson. Harkins, William D. Clark, George L. January 1900 (has links)
Thesis (PH. D.)--University of Chicago, 1919. / "Private Edition, Distributed by the University of Chicago Libraries, Chicago, Illinois." The first article is reprinted from a joint paper by W. D. Harkins, George L. Clark and Lathrop E. Roberts in the Journal of the American chemical society, vol. XLII, no. 4, April, 1920, and the second article is reprinted from vol. XLIV, no. 4, April, 1922, of the same journal. Includes bibliographical references. Also available on the Internet.
72

Hot surface ignition temperature of dust layers with and without combustible additives

Park, Haejun. January 2006 (has links)
Thesis (M.S.) -- Worcester Polytechnic Institute. / Keywords: Hot surface ignition temperature; self-heating; combustible liquid additives. Includes bibliographical references (leaves 134-135).
73

The thermodynamics of solutions and binary liquid mixtures

Mercer-Chalmers, June Dawn January 1993 (has links)
The thesis is presented in two parts. In part one, the excess thermodynamic properties have been determined for several binary liquid mixtures, with the aim of testing theories of liquid mixtures. The excess molar enthalpies, Hem, have been determined using an LKB flow microcalorimeter, and the excess molar volumes, Vem, have been determined using an Anton Paar densitometer. The HemS and VemS have been measured at 298.15 K for binary systems involving an alkanol (methanol, ethanol, I-propanol, 2-propanol) mixed with a hydrocarbon (l-hexene, I-heptene, l-octene, I-hexyne, I-heptyne, l-octyne, toluene, mesitylene, 0-, m-, or p-xylene, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclodecane). The results show trends relating to the degree of unsaturation, or size, of component molecules as well as the position of the hydroxyl group on the alkanol. Measurements were also made on mixtures involving an (n-alkane + a pseudo-n-alkane) and ( a cYcloalkane + a pseudo-cycloalkane). Two theories of liquid mixtures were tested in this work. The first theory tested was the theory of Congruency. This theory was tested, by means of a null test, on a novel set of mixtures involving an n-alkane (hexane, heptane, octane, decane, dodecane) + a pseudo-nalkane,and mixtures of a cycloalkane (cyclopentane, cyclohexane, cycloheptane, cyclooctane)+ a pseudo-cycloalkane. Deviations from the theory was less than the experimental error for the (n-alkane + pseudo-n-alkane) mixtures. However, significant deviations were observed for the mixtures of (a cycloalkane + a pseudo-cycloalkane). The second theory tested was the Flory theory, which has been used to predict the excess molar enthalpies and excess molar volumes for the mixtures involving (a 1-alkene, or 1-alkyne, or methyl-substituted benzene) + an alkanol. The results show that the theory does not hold for hydrocarbon mixtures involving an alkanol. In the second part of this thesis, the partial molar volumes, at infinite dilution, of binary solution involving a solid solute (18-crown-6 ether, dibenzo-18-crown-6 ether, dicyclohexanov 18-crown-6 ether, 15-crown-5 ether, or cryptand-222) are determined in various solvents. The results were repeated with a view to determine the volume changes at infinite dilution upon complexation, ΔV∞ of the crown ether or cryptand with a metal halide salt, MX (NaCl, NaI, KCl, KI, CsCl, CsI). The ΔV∞ results were compared with results in the literature for cryptand-222 (c-222) and dibenzo-18-crown-6 ether (B₂CE6) complexed with MX, and the study was extended to include further MX complexes with c-222 and B₂CE6, as well as MX complexes with 15-crown-5 ether and dicyclohexano-18-crown-6 ether. ΔV∞ results were correlated with the Hepler prediction of the electrostriction solvent effect.
74

Sampling of the phases within a liquid-liquid extraction spray column

Bergeron, Georges January 1963 (has links)
A study has been made of sampling techniques in a liquid-liquid extraction spray column using first a bell-shaped and a hook-shaped probe for the dispersed phase and for the continuous phase respectively. Later a piston method was attempted for the dispersed phase. The main interest in this research was the point concentration inside the column. At first, the time to reach steady state was considered in the absence of sampling. Later on, the rate of purging and sampling was varied for the probes up to 14.2 cc./min. for the continuous phase and 28.2 cc./min. for the dispersed phase. These rates were not sufficient to disturb the steady state. The measured point concentration was studied as a function of rate of sampling. Coalescence at the dispersed phase (bell-shaped) probe entrance did not take place. Finally, a piston sampler was set up and used in conjunction with the continuous phase (hook-shaped) probe as a second way to obtain point concentrations of the dispersed phase to compare with the results obtained with the bell-shaped probe. From these experiments, it can be concluded that sampling rate, varied from zero to 34.0 cc./min. for the continuous phase and from zero to 28.0 cc./min. for the dispersed phase, does not influence the point concentrations measured for column flows of 54.8 ft³/hr.-ft² and 72.4 ft³/hr.-ft² for the water and ketone phases respectively. The point concentration of the dispersed phase measured with the piston do not check definitively the results obtained with the bell-shaped probe; they do indicate that such agreement is fairly probable. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate
75

The solution to the reference hypernetted-chain approximation for fluids of hard spheres with dipoles and quadrupoles with application to liquid ammonia

Perkyns, John Stephen January 1985 (has links)
This thesis is divided into two parts. In Part A the reference hypernetted-chain (RHNC) approximation is solved for a fluid of hard spheres with embedded point dipoles and linear quadrupoles. The thermodynamic properties, the dielectric constant, ∈, and the pair correlation function are compared with previously calculated Monte Carlo data as well as with results from other integral equation methods. The RHNC is found to closely approximate the Monte Carlo results and is shown to improve on the other methods. In Part B a self-consistent mean field theory for molecular polarizability is used, together with the RHNC approximation used in Part A, for a polarizable dipole-linear quadrupole fluid with ammonia-like parameters. The dielectric constant is calculated at three sub-critical temperatures and it is found to be quite sensitive to the quadrupole moment. Experimental results for ∈ are shown to be well within the uncertainty, set by the quadrupole moment, in the calculated ∈ values. These calculated ∈ values are shown to be significantly larger than the dielectric constants for the equivalent non-polarizable system. / Science, Faculty of / Chemistry, Department of / Graduate
76

Transport properties of liquids and liquid mixtures and the theorem of corresponding states.

Doan, Manh Hung. January 1971 (has links)
No description available.
77

Liquid-liquid extraction in a spray column under ultrasonic vibration.

Chen, E. C. (Erh Chun) January 1968 (has links)
No description available.
78

Some Excess Thermodynamic Properties of Selected Polar-Nonpolar Binary Liquid Mixtures at Infinite Dilution

Afrashtehfar, Shapour January 1981 (has links)
No description available.
79

Electrochemical Oxidation of Ethanol in Ionic Liquids and Its Possible Use in Fuel Cells

Mason, Ashley M. 15 April 2010 (has links)
No description available.
80

Determination of the composition of mixtures of organic liquids by physical titration with water /

Habboush, Alberteen Eliya January 1959 (has links)
No description available.

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