1,854 Matching Results

Search Results

Advanced search parameters have been applied.

The Volume Thermodynamics of Liquids

Description: From preface: In the following chapters, I have commenced a serious study of the volume thermodynamics of liquids and solids. The work is, as yet, confined to volume, pressure, and temperature. Questions involving entropy and energy are also in active progress, but can not be included in the present bulletin.
Date: 1892
Creator: Barus, Carl
Partner: UNT Libraries Government Documents Department

Characterization of Novel Solvents and Absorbents for Chemical Separations

Description: Predictive methods have been employed to characterize chemical separation mediums including solvents and absorbents. These studies included creating Abraham solvation parameter models for room-temperature ionic liquids (RTILs) utilizing novel ion-specific and group contribution methodologies, polydimethyl siloxane (PDMS) utilizing standard methodology, and the micelles cetyltrimethylammonium bromide (CTAB) and sodium dodecylsulfate (SDS) utilizing a combined experimental setup methodology with indicator variables. These predictive models allows for the characterization of both standard and new chemicals for use in chemical separations including gas chromatography (GC), solid phase microextraction (SPME), and micellar electrokinetic chromatography (MEKC). Gas-to-RTIL and water-to-RTIL predictive models were created with a standard deviation of 0.112 and 0.139 log units, respectively, for the ion-specific model and with a standard deviation of 0.155 and 0.177 log units, respectively, for the group contribution fragment method. Enthalpy of solvation for solutes dissolved into ionic liquids predictive models were created with ion-specific coefficients to within standard deviations of 1.7 kJ/mol. These models allow for the characterization of studied ionic liquids as well as prediction of solute-solvent properties of previously unstudied ionic liquids. Predictive models were created for the logarithm of solute's gas-to-fiber sorption and water-to-fiber sorption coefficient for polydimethyl siloxane for wet and dry conditions. These models were created to standard deviations of 0.198 and 0.122 logunits for gas-to-PDMS wet and dry, respectively, as well as 0.164 and 0.134 log units for water-to-PDMS wet and dry, respectively. These models are particularly useful in solid phase microextraction separations. Micelles were studied to create predictive models of the measured micelle-water partition coefficient as well as models of measured MEKC chromatographic retention factors for CTAB and SDS. The resultant predictive models were created with standard deviations of 0.190 log units for the logarithm of the mole fraction concentration of water-to-CTAB, 0.171 log units for the combined logarithms of both the ...
Date: May 2011
Creator: Grubbs, Laura Michelle Sprunger
Partner: UNT Libraries

Study of Ether-, Alcohol-, or Cyano-Functionalized Ionic Liquids Using Inverse Gas Chromatography

Description: This article discusses the study of ether-, alcohol, or cyano-functionalized ionic liquids using inverse gas chromatography.
Date: March 11, 2010
Creator: Revelli, Anne-Laure; Mutelet, Fabrice; Jaubert, Jean-Noël; Garcia-Martinez, Marina; Sprunger, Laura M.; Acree, William E. (William Eugene) et al.
Partner: UNT College of Arts and Sciences

Partition Coefficients of Organic Compounds in Four New Tetraalkylammonium Bis(trifluoromethylsulfonyl)imide Ionic Liquids Using Inverse Gas Chromatography

Description: This article discusses partition coefficients of organic compounds in four new tetraalkylammonium bis(trifluoromethylsulfonyl)imide ionic liquids using inverse gas chromatography.
Date: August 18, 2011
Creator: Acree, William E. (William Eugene); Baker, Gary A.; Mutelet, Fabrice & Moïse, Jean-Charles
Partner: UNT College of Arts and Sciences

Technical assessment of BY-1 12 liquid observation well (LOW) anomalous readings

Description: This document contains a technical assessment of the cause and disposition of Interstitial Liquid Level(ILL) readings taken in February 1997 on Hanford waste tank 241-BY-112 that were below specified limits. Some readings were determined to be spurious while other readings were below the limit because of normal data scatter. The data assessment did discover that a new ILL had formed below the currently established baseline because of the normal drainage of the interstitial liquid over time. A new baseline and limit will be established. Because the new ILL appears to be stable and consistent with post saltwell pumping behavior, and because there is no other evidence to the contrary, the tank is judged not to be leaking.
Date: March 11, 1997
Creator: Barnes, D. A. & Reed, R. W.
Partner: UNT Libraries Government Documents Department

Nitrogen trailer acceptance test report

Description: This Acceptance Test Report documents compliance with the requirements of specification WHC-S-0249. The equipment was tested according to WHC-SD-WM-ATP-108 Rev.0. The equipment being tested is a portable contained nitrogen supply. The test was conducted at Norco`s facility.
Date: February 12, 1996
Creator: Kostelnik, A.J.
Partner: UNT Libraries Government Documents Department

Overcoming Thermal Shock Problems in Liquid Targets

Description: Short pulse accelerator-driven neutron sources such as the Spallation Neutron Source (SNS) employ high-energy proton beam energy deposition in heavy metal (such as mercury) over microsecond time frames. The interaction of the energetic proton beam with the mercury target leads to very high heating rates in the target. Although the resulting temperature rise is relatively small (a few {degree}C ), the rate of temperature rise is enormous ({approximately}10{sup 7} C/s) during the very brief beam pulse ({approximately}0.58 {micro}s). The resulting thermal-shock induced compression of the mercury leads to the production of large amplitude pressure waves in the mercury that interact with the walls of the mercury target and the bulk flow field. Safety-related operational concerns exist in two main areas, viz., (1) possible target enclosure failure from impact of thermal shocks on the wall due to its direct heating from the proton beam and the loads transferred from the mercury compression waves, and (2) impact of the compression-cum-rarefaction wave-induced effects such as cavitation bubble emanation and fluid surging. Preliminary stress evaluations indicate stress levels approaching yielding conditions and beyond in select regions of the target. Also, the induction of cavitation (which could assist in attenuation) can also release gases that may accumulate at undesirable locations and impair heat transfer.
Date: June 2000
Creator: Taleyarkhan, R. P. & Kim, S. H.
Partner: UNT Libraries Government Documents Department

Commentary on "Study of Assorted Interactions of an Ionic Liquid in Significant Solvent Systems using Compensated Equation of Fuoss Conductance and Vibrational Mode"

Description: Article offering commentary on the article titled "Study of assorted interactions of an ionic liquid in significant solvent systems using compensated equation of fuoss conductance and vibrational mode."
Date: May 1, 2014
Creator: Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences

Raman studies of reorientational dynamics in liquids

Description: Raman and/or infrared (IR) bandshape analysis to probe molecular dynamics in liquids has become a rapidly expanding field of study in recent years. Determination of spinning and tumbling diffusion constants, Dι and D⊥, which characterize the reorientation of symmetric-top moleclues has been successfully studied in a number of D6H and D3H molecules. For molecules of CV3 symmetry, however, previous attempts to extract spinning diffusion constants from Raman doubly degenerate vibrations (E mode) have proved unsuccessful. Presented here is a new methodology which resolves the problems encountered by former researchers through calculation of Dι utilizing the narrower Lorentzian component of E vibrations.
Date: December 1990
Creator: Wang, Shao-Pin
Partner: UNT Libraries