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Further calculations on solubility of 2-chloro-3-(trifluoromethyl)pyridine in ethanol + 1-propanol solvent mixtures at various temperatures

Description: This article reports on the reanalysis of reported calculations on solubility data of 2-chloro-3-(trifluoromethyl)pyridine in binary ethanol + 1-propanol solvent mixtures at various temperatures, and several additional points regarding the correlations.
Date: May 25, 2017
Creator: Jouyban, Abolghasem; Martínez, Fleming & Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences

Studying Acid-Base Equilibria in Two-Phase Solvent Media: Analyzing Results Using Aqueous Surfactant Solutions with Organic Solvents in the Titration of Analytes with Low Solubilities and Low Dissociation Constants

Description: Article discussing studying acid-base equilibria in two-phase solvent media and analyzing results using aqueous surfactant solutions with organic solvents in the titration of analytes with low solubilities with low dissociation constants.
Date: January 1, 1993
Creator: Tucker, Sheryl A. (Sheryl Ann); Amszi, Vicki L. & Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences

Solubility of Crystalline Nonelectrolyte Solutes in Organic Solvents: Mathematical Correlation of Benzil Solubilities with the Abraham General Solvation Model

Description: Article on the solubility of crystalline nonelectrolyte solutes in organic solvents and the mathematical correlation of benzil solubilities with the Abraham general solvation model.
Date: April 1, 2002
Creator: Acree, William E. (William Eugene) & Abraham, M. H. (Michael H.)
Partner: UNT College of Arts and Sciences

Comment on "Measurement and correlation of the solubility of p-coumaric acid in nine pure and water + ethanol mixed sovlents at temperatures from 293.15 to 333.15 K"

Description: This article provides comments on the article "Measurement and correlation of the solubility of p-coumaric acid in nine pure and water + ethanol mixed solvents at temperatures from 293.15 to 333.15 K" published in the Journal of Chemical and Engineering Data in 2016.
Date: December 7, 2016
Creator: Acree, William E. (William Eugene); Barrera, Maribel & Abraham, M. H. (Michael H.)
Partner: UNT College of Arts and Sciences

Tank 241-S-106, cores 183, 184 and 187 analytical results for the final report

Description: This document is the final laboratory report for tank 241-S-106 push mode core segments collected between February 12, 1997 and March 21, 1997. The segments were subsampled and analyzed in accordance with the Tank Push Mode Core Sampling and Analysis Plan (TSAP), the Tank Safety Screening Data Quality Objective (Safety DQO), the Historical Model Evaluation Data Requirements (Historical DQO) and the Data Quality Objective to Support Resolution of the Organic Complexant Safety Issue (Organic DQO). The analytical results are included in Table 1. Six of the twenty-four subsamples submitted for the differential scanning calorimetry (DSC) analysis exceeded the notification limit of 480 Joules/g stated in the DQO. Appropriate notifications were made. Total Organic Carbon (TOC) analyses were performed on all samples that produced exotherms during the DSC analysis. All results were less than the notification limit of three weight percent TOC. No cyanide analysis was performed, per agreement with the Tank Safety Program. None of the samples submitted for Total Alpha Activity exceeded notification limits as stated in the TSAP. Statistical evaluation of results by calculating the 95% upper confidence limit is not performed by the 222-S Laboratory and is not considered in this report. No core composites were created because there was insufficient solid material from any of the three core sampling events to generate a composite that would be representative of the tank contents.
Date: June 30, 1997
Creator: Esch, R.A.
Partner: UNT Libraries Government Documents Department

Commentary on "Measurement and Correlation of the Solubility of Telmisartan (Form A) in Nine Different Solvents from 277.85 to 338.35 K"

Description: This article presents the correct computation methodology for determining solute descriptors from experimental solubility data.
Date: November 11, 2016
Creator: Acree, William E. (William Eugene); Horton, Melissa Y.; Higgins, Elizabeth & Abraham, M. H. (Michael H.)
Partner: UNT College of Arts and Sciences

Laboratory Studies for Separation of Solids from Synthoil Gross Product : Parts 1 and 2

Description: PART 1. A variety of surfactants and agglomerating agents have been added to coal-liquefaction product (from the SYNTHOIL process) to determine the effectiveness of these agents in decreasing the viscosity of the product or inducing agglomeration of suspended solids in the product (and consequently facilitating the removal of solids from the product). More than two dozen additives were tested; however, only two of the additives caused a small reduction in the viscosity of the coal-liquefaction product. PART 2. A variety of organic solvents have been added to coal-liquefaction product (from the SYNTHOIL process) to determine the effectiveness in promoting the precipitation of suspended solids in the product. High-temperature settling of the product in the absence of foreign solvent does not appear to be a promising mechanism for solids removal from this product. However, the promoter-solvent de-ashing scheme has been demonstrated to be a potentially attractive solids-liquid separation method, and kerosene has been found to be an effective promoter solvent for the SYNTHOIL gross product.
Date: November 1976
Creator: Huang, H. & Fischer, J.
Partner: UNT Libraries Government Documents Department

Multicomponent Isotopic Separation and Recirculation Analysis

Description: A digital computer program for design of multi-component distillation columns has been developed based on an exact method of solution of the governing equations. Although this computer program was developed for enrichment of the spent fuels from presently conceived Tokamak-type fusion power reactors by cryogenic distillation, the program can be used for the design of any multi-component distillation column, provided, of course, the necessary thermodynamic and phase equilibrium data are available. To prove the versatility of the computer program, parametric investigations to study the effect of design and operating variables on the composition of the product streams was carried out for the case of separating hydrogen isotopes. The computer program is very efficient; hence, a number of parametric investigations can be carried out with limited resources. The program does, however, require a fairly large computer storage space (approximately 250 K bytes).
Date: January 1976
Creator: Misra, B. & Maroni, V. A.
Partner: UNT Libraries Government Documents Department

Alkaline detergent recycling via ultrafiltration

Description: The metal finishing industry uses alkaline cleaners and detergents to remove oils and dirt from manufactured parts, often before they are painted or plated. The use of these cleaners has grown because environmental regulations are phasing out ozone depleting substances and placing restrictions on the use and disposal of many hazardous solvents. Lawrence Livermore National Laboratory is examining ultrafiltration as a cleaning approach that reclaims the cleaning solutions and minimizes wastes. The ultrafiltration membrane is made from sheets of polymerized organic film. The sheets are rolled onto a supporting frame and installed in a tube. Spent cleaning solution is pumped into a filter chamber and filtered through the membrane that captures oils and dirt and allows water and detergent to pass. The membrane is monitored and when pressure builds from oil and dirt, an automatic system cleans the surface to maintain solution flow and filtration quality. The results show that the ultrafiltration does not disturb the detergent concentration or alkalinity but removed almost all the oils and dirt leaving the solution in condition to be reused.
Date: June 1, 1995
Creator: Steffani, C. & Meltzer, M.
Partner: UNT Libraries Government Documents Department

Alternatives for the disposition of PUREX organic solution

Description: This Supporting Document submits options and recommendations for final management of Tank 40 Plutonium-Uranium Extraction (PUREX) Plant organic solution per Tri-Party Agreement Milestorm Number M-80-00-T03. Hanford is deactivating the PUREX Plant for the US DOE. One the key element of this Deactivation is disposition of approximately 81,300 liters (21,500 gallons) of slightly radioactively contaminated organic solution to reduce risk to the environment, reduce cost of long-term storage, and assure regulatory compliance. An announcement in the Commerce Business Daily (CBD) on October 14, 1994 has resulted in the submission of proposals from two facilities capabLe of receiving and thermally destroying the solution. Total decomposition by thermal destruction is the recommended option for the disposition of the PUREX organic solution and WHC is evaluating the proposals from the two facilities.
Date: June 16, 1995
Creator: Nelson, D.W.
Partner: UNT Libraries Government Documents Department

Reclamation and reuse of Freon in total petroleum hydrocarbon analyses

Description: At the Savannah River Technology Center (SRTC), we have successfully demonstrated the use of a solvent recycling system to reclaim spent Freon solvent in total petroleum hydrocarbon (TPH) analyses of radioactive samples. A wide variety of sample types including ground water, organics, laboratory waste, process control, sludge, soils, and others are received by our lab for total petroleum hydrocarbon analysis. This paper demonstrates the successful use of a commercially available carbon bed recycle system which we modified to enable the recovery of 95-98 percent of the radioactive contaminated Freon. This system has been used successfully in our lab for the past three years.
Date: December 31, 1997
Creator: Ekechukwu, A.A. & Young, J.E.
Partner: UNT Libraries Government Documents Department

D-area oil seepage basin bioventing optimization test plan

Description: The D Area Oil Seepage Basin (DOSB) was used from 1952 to 1975 for disposal of petroleum-based products (waste oils), general office and cafeteria waste, and apparently some solvents [trichloroethylene (TCE)/tetrachloroethylene (PCE)]. Numerous analytical results have indicated the presence of TCE and its degradation product vinyl chloride in groundwater in and around the unit, and of petroleum hydrocarbons in soils within the unit. The DOSB is slated for additional assessment and perhaps for environmental remediation. In situ bioremediation represents a technology of demonstrated effectiveness in the reclamation of sites contaminated with petroleum hydrocarbons and chlorinated solvents, and has been retained as an alternative for the cleanup of the DOSB. The Savannah River Site is therefore proposing to conduct a field treatability study designed to demonstrate and optimize the effectiveness of in situ microbiological biodegradative processes at the DOSB. The introduction of air and gaseous nutrients via two horizontal injection wells (bioventing) is expected to enhance biodegradation rates of petroleum components and stimulate microbial degradation of chlorinated solvents. The data gathered in this test will allow a determination of the biodegradation rates of contaminants of concern in the soil and groundwater, allow an evaluation of the feasibility of in situ bioremediation of soil and groundwater at the DOSB, and provide data necessary for the functional design criteria for the final remediation system.
Date: December 31, 1998
Creator: Berry, C.J.; Radway, J.C.; Alman, D. & Hazen, T.C.
Partner: UNT Libraries Government Documents Department

Vapor-liquid equilibria for copolymer+solvent systems: Effect of intramolecular repulsion

Description: Role of intramolecular interactions in blend miscibility is well documented for polymer+copolymer mixtures. Some copolymer+polymer mixtures are miscible although their corresponding homopolymers are not miscible; for example, over a range of acrylonitrile content, styrene/acrylonitrile copolymers are miscible with poly(methyl methacrylate) but neither polystyrene nor polyacrylonitrile is miscible with poly(methyl methacrylate). Similarly, over a composition range, butadiene/acrylonitrile copolymers are miscible with poly(vinyl chloride) while none of the binary combinations of the homopolymers [polybutadiene, polyacrylonitrile, and poly(vinyl chloride)] are miscible. This behavior has been attributed to ``intramolecular repulsion`` between unlike copolymer segments. We have observed similar behavior in vapor-liquid equilibria (VLE) of copolymer+solvent systems. We find that acrylonitrile/butadiene copolymers have higher affinity for acetonitrile solvent than do polyacrylonitrile or polybutadiene. We attribute this non-intuitive behavior to ``intramolecular repulsion`` between unlike segments of the copolymer. This repulsive interaction is weakened when acetonitrile molecules are in the vicinity of unlike copolymer segments, favoring copolymer+solvent miscibility. We find similar behavior when acetonitrile is replaced by methyl ethyl ketone. To best knowledge, this effect has not been reported previously for VLE. We have obtained VLE data for mixtures containing a solvent and a copolymer as a function of copolymer composition. It appears that, at a given solvent partial pressure, there may be copolymer composition that yields maximum absorption of the solvent. This highly non-ideal VLE phase behavior may be useful for optimum design of a membrane for a separation process.
Date: March 1, 1995
Creator: Gupta, R.B. & Prausnitz, J.M.
Partner: UNT Libraries Government Documents Department

ABSORPTION CHANGES IN BACTERIAL CHROMATOPHORES. II. A NEWCHLOROPHYLL-LIKE PIGMENT FROM THE OXIDATION OF CHROMATOPHORES FROMRHODOSPIRILLUM RUBRUM

Description: Evidence is presented which points to (at least) two bound forms of bacteriochlorophyll present in chromatophores of Rhodospirillum rubrum, both of them readily converted to unbound bacteriochlorophyll (abs. max. 770 mu) when the chromatophores are extracted with acetone or ethanol. Controlled oxidation of the chromatophores with Ir(IV) or with Zn(II) and ferricyanide preferentially destroys the more strongly absorbing pigment (abs. max. 880 mu) but brings about only a slight decrease in the magnitude of the photoinduced absorption changes at 810 and 792 mu. Such oxidations yield a new pigment, absorbing at 715 mu in the aqueous preparation and, more strongly, at 680-684 mu when the pigment is extracted into organic solvents. This pigment is formed irreversibly and is therefore different from the material formed by photooxidation of chromatophores. Its visible spectrum and the spectrum of the material formed from it by acidification suggest that it is a chlorophyll-like substance, possibly derived from bacteriochlorophyll by (two-electron) oxidation of one of the dihydropyrrole rings to a pyrrole ring. Directions are given for separation of this pigment from other colored compounds present in the oxidation mixtures.
Date: October 1, 1964
Creator: Gould, Edwin S.; Kuntz Jr., Irwin D. & Calvin, Melvin
Partner: UNT Libraries Government Documents Department

Summary Of Identification Of Rrgulatory Acceptability Of Enhanced Attenuation Categories

Description: Chlorinated solvents once introduced to the subsurface are a persistent contaminant. Though many types of active treatments have been developed and deployed to treat contaminated sites, most sites will ultimately incorporate the use of passive treatments into the remediation process. A process favored by many is the use of Monitored Natural Attenuation that relies on the natural attenuation processes occurring within the system to remediate the contaminants. However, it is likely there will be instances where the natural attenuation processes will be insufficient to reduce the level of contamination to acceptable levels in an acceptable span of time. Rather than redeploying source treatments, the Department of Energy along with the Interstate Technology and Regulatory Council (ITRC) are developing the concept of Enhanced Attenuation (EA). An enhancement is any type of intervention that might be implemented in a source-plume system that increases the magnitude of attenuation by natural processes beyond that which occurs without intervention. Enhanced Attenuation is the result of applying an enhancement or intervention technique that will sustainably manipulate a natural attenuation process leading to an increased reduction in mass flux of contaminants. Efforts are moving forward along several fronts in developing this concept. This effort is a follow-on to initial discussions with site owners, regulators and stakeholder organizations in the development of the concepts of Enhanced Attenuation, the use of mass balance to evaluate the stability of a waste site/groundwater plume, and identification of tools that will support characterization and monitoring efforts for MNA and EA treatments. Those discussions are documented in the report titled ''Summary Document of Workshops for Hanford, Oak Ridge and Savannah River Site as part of the Monitored Natural Attenuation and Enhanced Passive Remediation for Chlorinated Solvents-DOE Alternative Project for Technology Acceleration'' (WSRC, 2003). The objective of this report is to document the May ...
Date: January 4, 2006
Creator: Vangelas, K
Partner: UNT Libraries Government Documents Department

SCENARIOS EVALUATION TOOL FOR CHLORINATED SOLVENT MNA

Description: Over the past three decades, much progress has been made in the remediation of chlorinated solvents from the subsurface. Yet these pervasive contaminants continue to present a significant challenge to the U.S. Department of Energy (DOE), other federal agencies, and other public and private organizations. The physical and chemical properties of chlorinated solvents make it difficult to rapidly reach the low concentrations typically set as regulatory limits. These technical challenges often result in high costs and long remediation time frames. In 2003, the DOE through the Office of Environmental Management funded a science-based technical project that uses the U.S. Environmental Protection Agency's technical protocol (EPA, 1998) and directives (EPA, 1999) on Monitored Natural Attenuation (MNA) as the foundation on which to introduce supporting concepts and new scientific developments that will support remediation of chlorinated solvents based on natural attenuation processes. This project supports the direction in which many site owners want to move to complete the remediation of their site(s), that being to complete the active treatment portion of the remedial effort and transition into MNA. The overarching objective of the effort was to examine environmental remedies that are based on natural processes--remedies such as Monitored Natural Attenuation (MNA) or Enhanced Attenuation (EA). The research program did identify several specific opportunities for advances based on: (1) mass balance as the central framework for attenuation based remedies, (2) scientific advancements and achievements during the past ten years, (3) regulatory and policy development and real-world experience using MNA, and (4) exploration of various ideas for integrating attenuation remedies into a systematic set of ''combined remedies'' for contaminated sites. These opportunities are summarized herein and are addressed in more detail in referenced project documents and journal articles, as well as in the technical and regulatory documents being developed within the ITRC. Three topic ...
Date: August 16, 2006
Creator: Vangelas, K; Brian02 Looney, B; Truex, Michael J. & Newell, Charles J.
Partner: UNT Libraries Government Documents Department