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Robert N. Goldberg, Yadu D. Tewari, Talapady N. Bhat
This review serves to update previously published evaluations of equilibrium constants and enthalpy changes for enzyme catalyzed reactions. For each reaction the following information is given: the reference for the data; the reaction studied; the name of
This article provides practical guidance for the use of Henry's law in design calculations, with emphasis on solutes in aqueous systems at conditions characteristic of wastewater cleanup operations. Particular attention is given to the temperature
We determined the zero-density viscosity eta of hydrogen, methane and argon in the temperature range 200 K to 400 K, with standard uncertainties of 0.084 % for hydrogen and argon and 0.096 % for methane. These uncertainties are dominated by the uncertainty
Recently, we reported a method and apparatus for the advanced measurement of distillation curves. The new method allows for increased precision in the measurement of distillation curves as well as a composition-explicit channel of data. Herein, we report a
Qian Dong, Chris D. Muzny, Andrei F. Kazakov, Vladimir Diky, Joe W. Magee, Jason A. Widegren, Robert D. Chirico, Kenneth N. Marsh, Michael D. Frenkel
The development, scope, and functionality of the web-based ionic liquids database, ILThermo, are described. The database is available free to the public, and aims to provide users worldwide with up-to-date information from publications of experimental
We have recently introduced several important improvements in the measurement of distillation curves for complex fluids. The modifications to the classical measurement provide for (1) a composition explicit data channel for each distillate fraction (for
The thermodynamic parameters, DBGo, DBHo, and DBSo, of the drugs flurbiprofen (FLP), nabumetone (NAB), and naproxen (NPX) binding to b-cyclodextrin (bCD) and to g-cyclodextrin (gCD) in 0.10 M sodium phosphate buffer were determined from isothermal
James W. Schmidt, R Gavioso, E May, Michael R. Moldover
Using a quasi-spherical, microwave cavity resonator, we measured the refractive index of helium to deduce its molar polarizability A ε in the limit of zero density. We obtained (A ε,meas - A ε,theory)/A ε = (-1.8plus or minus} 8.4)× 10 -6, where the
Jason A. Widegren, Yi-ming Wang, Wesley A. Henderson, Joe W. Magee
The relative volatilities of a variety of common, aprotic ionic liquids have been determined for the first time. Equimolar mixtures of ionic liquids were vacuum distilled in a glass sublimation apparatus at approximately 473 K. The composition of the
Robert D. Chirico, Russell D. Johnson III, William Steele
Measurements leading to the calculation of the standard thermodynamic properties for gaseous 2,6-dimethylquinoline (Chemical Abstracts registry number [877-43-0]) are reported. Experimental methods included adiabatic heat-capacity calorimetry, vibrating
Densities, vapor pressures, and the critical point were measured for dimethyl ether, thus filling several gaps in the thermodynamic data for this compound. Densities were measured with a computer-controlled high temperature, high-pressure vibrating-tube
Michael D. Frenkel, Robert D. Chirico, Vladimir Diky, Chris D. Muzny, Qian Dong, K N. Marsh, John H. Dymond, William A. Wakeham, Stephen E. Stein, Erich Koenigsberger, Anthony R. Goodwin, Joe W. Magee, Michiel Thijssen, William M. Haynes, Suphat Watanasiri, Marco Satyro, Martin Schmidt, Andrew I. Johns, Gary R. Hardin
Thermodynamic data often represent a key resource in the search for new relationships between properties of chemical systems that constitutes the basis of the scientific discovery process. In addition, thermodynamic information is critical for development
In previous work, several significant improvements in the measurement of distillation curves for complex fluids were introduced. The modifications to the classical measurement provide for (1) temperature and volume measurement(s) of low uncertainty, and
In previous work, several significant improvements in the measurement of distillation curves for complex fluids were introduced. The modifications to the classical measurement provide for (1) temperature and volume measurement(s) of low uncertainty, (2)
The development of technical equations of state using the 12-parameter Span-Wagner functional form for four siloxanes is presented in two parts. The fluids under investigation include hexamethyldisiloxane (MM), tetradecamethylhexasiloxane (MD4M)
In this short note we present a method and a simple apparatus for use with simple, fractional and steam distillation operations in which the operator requires a precise measurement of instantaneous distillate composition as the distillation proceeds. There
We used a quasi-spherical cavity as an acoustic and microwave resonator to measure the thermodynamic temperatures T of the triple points of mercury, argon, neon, and equilibrium hydrogen, and to measure the difference T - T90, in the range 7 K to 273 K.
Michael D. Frenkel, Robert D. Chirico, Vladimir Diky, Xinjian Yan, Qian Dong, Chris D. Muzny
The first full-scale software implementation of the dynamic data evaluation concept {ThermoData Engine (TDE)} is described for thermophysical and thermochemical property data. This concept requires the development of large electronic databases capable of
Water and aqueous systems are widely used in metrology, which is a major focus of the National Institute of Standards and Technology (NIST). Standards such as those produced by IAPWS can be used to calibrate instruments and validate protocols. In this work
Vladimir Rohac, Kvetoslav Ruzicka, Vlastimil Ruzicka, Dzmitry H. Zaitsau, Gennady J. Kabo, Vladimir Diky, Karel Aim
Measurements of vapour pressure in the liquid phase and of enthalpy of vaporisation and results of calculation of ideal gas properties for diethyl phthalate are reported. The method of comparative ebulliometry, the static method, and the Knudsen mass loss
Yadu D. Tewari, T. Ihara, Karen W. Phinney, M P. Mayhew
The time course and thermodynamics of the lipase-catalyzed transesterification reaction (benzl alcohol + butyl acetate = benzyl acetate + 1-butanol) has been studied in supercritical carbon dioxide (SCCO 2), n-hexane, toluene, and neat media (no solvent
A new correlation has been developed to represent the second virial coefficient of water (H2O) as a function of temperature. The formulation was fitted to experimental data, both for the second virial coefficient itself and for a quantity related to its
Robert D. Chirico, Michael D. Frenkel, Vladimir Diky, K N. Marsh, R C. Wilhoit
ThermoML is an XML-based approach for storage and exhange of experimental and critically evaluated thermophysical and thermochemical property data. Extensions to the ThermoML schema for the expression of uncertainties are described. Basic principles, scope