The phase behavior of aqueous solutions of temperature-responsive (ethylene oxide)/ethylene copolymers with tunable lower critical solution temperatures (LCST) is explored using an equation of state approach. The LCST in water of these polymers is tailored by their chemical composition, specifically by the balance of hydrophilic to hydrophobic groups in the polymer. The general formalism of the...

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Supercritical water oxidation has attracted attention of many researchers ever since the ideahas emerged about three decades ago as a promising technique in the waste managementindustry. Providing more details about the behavior of a supercritical water oxidation systemunder various operating conditions and extending available data can greatly assist more accurateand reliable design of such sys...

A series of nonempirical calculations are reported on the excited states of the ethylene molecule using a recent minimum basis set LCAO MO SCF wavefunction. For the lowest excited singlet state of ethylene ( 1Bau) the coupling between the 1r electrons and u electrons is significant: the excitation energy being decreased from 11.98 to 10.17 eV and the oscillator strength from 1.03 to 0.73. This ...

Hydrogenation of various types of oleochemicals is a major unit operation in industry. Natural fatty alcohols are important raw materials for surfactants and lubricants and can be produced by catalytic hydrogenation of fatty acid methyl esters (FAME). Commercial multiphase processes are necessarily operated at high pressures and high hydrogen-to-ester mole ration owing to low solubility of hydr...

The state of aggregation of water dissolved in supercritical carbon dioxide has been investigated under isobaric heating (T=40-340°C, P=250 bar) using infrared absorption and Raman scattering spectroscopies. Quantitative analysis of experimental spectra has shown that below 100°C, water exists only in its monomeric form (solitary water surrounded by CO2 molecules) whereas H-bonded species, name...

A novel class of nonequilibrium phase transitions at zero temperature is found in chains of nonlinear oscillators. For two paradigmatic systems, the Hamiltonian XY model and the discrete nonlinear Schrödinger equation, we find that the application of boundary forces induces two synchronized phases, separated by a nontrivial interfacial region where the kinetic temperature is finite. Dynamics in...

Carbon dioxide can be used in its liquid (near critical) or supercritical fluid state as a replacement for conventional cleaning solvents, reducing the pollution associated with the operations that would otherwise require significant amounts of volatile organic compounds, ozone depleting substances, or hazardous air pollutants. The results of several near critical/supercritical parts cleaning a...