Aqueous Nonelectrolyte Solutions. Part IX. Enthalpies of Mixing of Water and Deuterium Oxide with Ethylene Oxide

Calorimetric enthalpies of mixing have been measured over the whole composition range for the water – ethylene oxide system at 10.75 and 20.00 °C and for the deuterium oxide – ethylene oxide system at 13.45 and 20.00 °C. Less extensive measurements have been made for dilute ethylene oxide solutions in water at 0.6 °C and in deuterium oxide at 4.1 and 7.3 °C. The experimental S-shaped, enthalpy of mixing – composition curves are interpreted in terms of solution hydrogen bonding changes, with particular reference to the hydrogen bonding of water. At low ethylene oxide mole fractions the deuterium oxide systems are more exothermal and at high ethylene oxide mole fractions more endothermal than the corresponding water systems. A good correlation is found between the enthalpy of mixing and the water proton magnetic resonance chemical shift for solutions with greater than 0.55 mol fraction of ethylene oxide.

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Aqueous Nonelectrolyte Solutions. Part XII. Enthalpies of Mixing of Water and Deuterium Oxide with Tetrahydrofuran

Canadian Journal of Chemistry ◽

10.1139/v73-289 ◽

1973 ◽

Vol 51 (12) ◽

pp. 1933-1940 ◽

Cited By ~ 35

Author(s):

David N. Glew ◽

Harry Watts

Keyword(s):

Hydrogen Bonding ◽

Proton Magnetic Resonance ◽

Composition Range ◽

Deuterium Oxide ◽

Enthalpy Of Mixing ◽

Water Systems ◽

Water Proton ◽

Oxide Systems ◽

Enthalpies Of Mixing ◽

Water Hydrogen

Calorimetric enthalpies of mixing have been measured over the whole composition range for the water–tetrahydrofuran and the deuterium oxide – tetrahydrofuran systems at 10.00 and 25.00 °C. The experimental S-shaped, enthalpy of mixing –composition curves are interpreted in terms of changes of the water hydrogen bonding in solution. At low tetrahydrofuran mole fractions the deuterium oxide systems are more exothermal and at high tetrahydrofuran mole fractions more endothermal than the corresponding water systems. A good correlation is found between the enthalpy of mixing and the water proton magnetic resonance chemical shift for solutions with greater than 0.55 mole fraction of tetrahydrofuran.

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Calorimetric Investigation of MCI-EuCI2 Melts (M = Na, K, Rb)

Zeitschrift für Naturforschung A ◽

10.1515/zna-2001-0908 ◽

2001 ◽

Vol 56 (9-10) ◽

pp. 653-657

Author(s):

F. Da Silva ◽

L. Rycerz ◽

M. Gaune-Escard

Keyword(s):

Least Squares ◽

Interaction Parameter ◽

Atmospheric Pressure ◽

Binary Systems ◽

Composition Range ◽

Enthalpy Of Mixing ◽

Mixing Enthalpy ◽

Calorimetric Investigation ◽

Direct Calorimetry ◽

Enthalpies Of Mixing

Abstract The molar enthalpies of mixing (ΔmixHm) of MCl-EuCl2 (M = Na, K, Rb) liquid binary systems were measured at 1138 K over the whole composition range by direct calorimetry. A Calvet type calorimeter was used, and mixing of the two liquid components was achieved by the ampoule break-off technique under argon at atmospheric pressure. The enthalpy of mixing of these systems is negative over the whole composition range with a minimum of approximately -0.5, -3.5 and -4.5 kJ mol-1 for M = Na, K, Rb, respectively. The least-squares coefficients A, B, C in the equation A (kJ mol-1) = A + B x + C x2, where λ is an interaction parameter, are reported. From the trend observed in these MCl-EuCl2 systems it was possible to estimate the mixing enthalpy of the CsCl-EuCl2 system.

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Aqueous nonelectrolyte solutions. Part XIV. D-ice and D-hydrate freezing points of deuterium oxide – ethylene oxide solutions and the formula of congruent ethylene oxide D-hydrate

Canadian Journal of Chemistry ◽

10.1139/v96-204 ◽

1996 ◽

Vol 74 (10) ◽

pp. 1830-1835

Author(s):

David N. Glew ◽

Norman S. Rath

Keyword(s):

Ethylene Oxide ◽

Composition Range ◽

Deuterium Oxide ◽

Hydrate Formation ◽

Single Measurement ◽

Method Of Least Squares ◽

Cooling Method ◽

Dynamic Cooling ◽

Freezing Temperatures ◽

Freezing Curve

D-ice freezing temperatures and D-hydrate formation temperatures have been measured by the dynamic cooling method for deuterium oxide – ethylene oxide (EO) solutions containing from 0 to 95.5 mol% EO. The D-ice and the congruent EO D-hydrate freezing temperatures exhibited standard errors (SEs) on a single measurement of 0.004 °C and 0.017 °C, respectively. The D-ice–D-hydrate eutectic temperature was observed at 1.500 °C with standard error (SE) 0.002 °C and at composition 2.207 mol% EO with SE 0.010 mol% EO. The congruent EO D-hydrate was found to freeze at 13.242 °C with SE 0.007 °C and at composition 12.60 mol% EO with SE 0.07 mol% EO. The formula of the congruent EO D-hydrate was EO•6.93D2O with SE 0.045 mol D2O/mol EO. Only one type of D-hydrate was found over the whole composition range down to −23 °C: the shoulder of the D-hydrate freezing curve above 40 mol% EO resulted from the high activity coefficients of dilute deuterium oxide in concentrated EO solutions. Equations and best values for the D-ice freezing temperatures and the D-hydrate formation temperatures together with their SEs were evaluated by the method of least squares. Properties of EO D-hydrate are compared with those of EO hydrate. Key words: clathrate D-hydrate of ethylene oxide, freezing of deuterium oxide – ethylene oxide, ethylene oxide D-hydrate, formula of ethylene oxide D-hydrate.

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The Investigation of Lipid-Water Systems, Part 3. Nuclear Magnetic Resonance in the Mono-Octanoin-Deuterium Oxide System

Liquid Crystals and Ordered Fluids ◽

10.1007/978-1-4684-8214-0_20 ◽

1970 ◽

pp. 277-288 ◽

Cited By ~ 3

Author(s):

B. Ellis ◽

A. S. C. Lawrence ◽

M. P. Mc.Donald ◽

W. E. Peel

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Deuterium Oxide ◽

Water Systems ◽

Oxide System ◽

Nuclear Magnetic

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Thermodynamic Database of P2O5-containing Oxide Systems for the Dephosphorization Process in Steelmaking

High Temperature Materials and Processes ◽

10.1515/htmp-2012-0132 ◽

2013 ◽

Vol 32 (3) ◽

pp. 247-254 ◽

Cited By ~ 8

Author(s):

In-Ho Jung ◽

Pierre Hudon ◽

Wan-Yi Kim ◽

Marie-Aline van Ende ◽

Miftaur Rahman ◽

...

Keyword(s):

Thermodynamic Modeling ◽

Basic Oxygen Furnace ◽

Oxide System ◽

Thermodynamic Database ◽

Experimental Investigations ◽

Oxide Systems ◽

Basic Oxide ◽

Basic Oxygen ◽

Process Route ◽

P Removal

AbstractThe Na2O-MgO-CaO-FeO-Fe2O3-Al2O3-SiO2-P2O5 system is a basic oxide system for the Basic Oxygen Furnace (BOF) process as well as the hot metal dephosphorization process. Numerous experimental investigations on this oxide system are being carried out to find out an advanced process route for P removal from molten iron. In spite of their industrial importance, however, phase equilibria in oxide systems containing P2O5 have not been well investigated due to the complexity of their chemistry. No systematic thermodynamic modeling of these systems has been conducted to date, either. In order to meet the strong demands of steelmaking and other industries, new systematic thermodynamic modeling of the P2O5-containing oxide systems (Na2O-MgO-CaO-FeO-Fe2O3-Al2O3-SiO2-P2O5) and key phase diagram experiments have been carried out over the past years. In the present study, the results of the thermodynamic modeling of unary, binary and ternary P2O5-containing systems and the applications of the thermodynamic database to the dephosphorization by multi-component slag in BOF process are presented in comparison with experimental data. All thermodynamic calculations were performed using FactSage thermodynamic software.

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Use of Biological Indicators Designed for Stream or Ethylene Oxide to Monitor a Liquid Chemical Sterilization Process

Infection Control and Hospital Epidemiology ◽

10.1086/646749 ◽

1993 ◽

Vol 14 (6) ◽

pp. 313-319 ◽

Cited By ~ 4

Author(s):

Raymond C. Kralovic

Keyword(s):

Ethylene Oxide ◽

In Vitro Tests ◽

Oxide Systems ◽

Performance Specifications ◽

Chemical Sterilization ◽

Sterilization Process ◽

Liquid Chemical ◽

D Values ◽

System 1

AbstractObjective:To determine the ability of a commercially available biological indicator (BI), used to monitor steam and ethylene oxide sterilization, to biologically monitor a liquid sterilization process consisting of a sterile processor, a proprietary peracetic acid sterilant, and a sterile rinse system.Design:Analysis of spore survival in BIs tested in STERIS SYSTEM 1™ liquid chemical sterilization processor and in vitro.Setting:STERIS Corp. research laboratory.Methods:In vitro tests were performed in the STERIS SYSTEM 1 Processor using 12-minute and 6-minute sterilant exposure cycles. D values (time to inactivate one log of spores), spore washoff and outgrowth time, and inhibitory effects of the sterilant were determined.Results:Sterilization of the spore-inoculated filter paper strips in the BIs was ascertained in both processor testing and in vitro tests using conditions identical to those in the processor. The extensive washing and dilution during the processor cycle resulted in only 0.2% and 1.8% removal of the spores from Bacillus stearother-mophilus and Bacillus subtilis inoculated spore strips, respectively.Carryover of the diluted sterilant to the culture medium did not inhibit the outgrowth of the spores, and D values could be obtained. B Stearothermophilus was two to three times more resistant to the sterilant than B subtilis. However, either spore meets the performance specifications applicable to BIs for monitoring sterilization processes.Conclusions:The data demonstrate that the commercial Bis evaluated are reproducible and verifiable indicators of the liquid chemical sterilization process. The same kind of performance specifications for producing BIs used to monitor steam or ethylene oxide systems also apply to the evaluated liquid chemical sterilization system.

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