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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

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

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

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

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

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

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

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

Monitored Natural Attenuation and Enhanced Attenuation for Chlorinated Solvent Plumes - It’s All About Balance

Description: Nature's inherent ability to cleanse itself is at the heart of Monitored Natural Attenuation (MNA). The complexity comes when one attempts to measure and calculate this inherent ability, called the Natural Attenuation Capacity (NAC), and determine if it is sufficient to cleanse the system to agreed upon criteria. An approach that is simple in concept for determining whether the NAC is sufficient for MNA to work is the concept of a mass balance. Mass balance is a robust framework upon which all decisions can be made. The inflows to and outflows from the system are balanced against the NAC of the subsurface system. For MNA to be acceptable, the NAC is balanced against the contaminant loading to the subsurface system with the resulting outflow from the system being in a range that is acceptable to the regulating and decision-making parties. When the system is such that the resulting outflow is not within an acceptable range, the idea of taking actions that are sustainable and that will bring the system within the acceptable range of outflows is evaluated. These sustainable enhancements are being developed under the Enhanced Attenuation (EA) concept.
Date: May 19, 2005
Creator: VANGELAS, KAREN
Partner: UNT Libraries Government Documents Department

Monitored Natural Attenuation of Chlorinated Solvents - Moving Beyond Reuctive Dechlorination

Description: Monitored natural attenuation (MNA), while a remedy of choice for many sites, can be challenging when the contaminants are chlorinated solvents. Even with many high quality technical guidance references available there continue to be challenges implementing MNA at some chlorinated solvent sites. The U.S. Department of Energy, as one organization facing such challenges, is leading a project that will incorporate developing concepts and tools into the existing toolbox for selecting and implementing MNA as a remediation option at sites with chlorinated solvents contamination. The structure and goals of this project were introduced in an article in the Winter 2004 issue of Remediation (Sink et al.). This article is a summary of the three technical areas being developed through the project: mass balance, enhanced attenuation, and characterization and monitoring supporting the first two areas. These topics will be documented in separate reports available from the US Department of Energy Office of Scientific and Technical Information at www.osti.gov.
Date: April 10, 2006
Creator: Vangelas, K
Partner: UNT Libraries Government Documents Department

Method to prepare Semtex

Description: This procedure requires the binder and uncoated RDX be prepared in separate steps, see Figure 1: (1) The binder and dye are mixed by agitation with a water-insoluble organic solvent (e.g., toluene), I; (2) The RDX/PETN is agitated thoroughly with water, II; (3) The binder solution I is added to the RDX/water mixture at II with thorough mixing to form a slurry III; (4) In the next step the solvent is distilled off at IV leaving resulting granules; (5) The next step is followed by filtration at V, which may be done by vacuum; (6) The composition is then dried at VI to a dough-like consistency.
Date: November 26, 2006
Creator: Alcaraz, A & Dougan, A
Partner: UNT Libraries Government Documents Department

Multiple Lines Of Evidence Supporting Natural Attenuation: Lines Of Inquiry Supporting Monitored Natural Attenuation And Enhanced Attenuatin Of Chlorinated Solvents

Description: The Department of Energy (DOE) is sponsoring an initiative to facilitate efficient, effective and responsible use of Monitored Natural Attenuation (MNA) and Enhanced Attenuation (EA) for chlorinated solvents. This Office of Environmental Management (EM) ''Alternative Project,'' focuses on providing scientific and policy support for MNA/EA. A broadly representative working group of scientists supports the project along with partnerships with regulatory organizations such as the Interstate Technology Regulatory Council (ITRC) and the United States Environmental Protection Agency (USEPA). The initial product of the technical working group was a summary report that articulated the conceptual approach and central scientific tenants of the project, and that identified a prioritized listing of technical targets for field research. This report documented the process in which: (1) scientific ground rules were developed, (2) lines of inquiry were identified and then critically evaluated, (3) promising applied research topics were highlighted in the various lines of inquiry, and (4) these were discussed and prioritized. The summary report will serve as a resource to guide management and decision making throughout the period of the subject MNA/EA Alternative Project. To support and more fully document the information presented in the summary report, the DOE is publishing a series of supplemental documents that present the full texts from the technical analyses within the various lines of inquiry (see listing). The following report--documenting our evaluation of the state of the science for the lines of evidence for supporting decision-making for MNA--is one of those supplemental documents.
Date: December 31, 2004
Creator: Vangelas, Karen; Widemeirer, T. H.; Barden, M.J.; Dickson, W. Z. & Major, David
Partner: UNT Libraries Government Documents Department

CARBON DIOXIDE SEPARATION BY PHASE ENHANCED GAS-LIQUID ABSORPTION

Description: A new process called phase enhanced gas-liquid absorption has been developed in its early stage. It was found that adding another phase into the absorption system of gas/aqueous phase could enhance the absorption rate. A system with three phases was studied. In the system, gas phase was carbon dioxide. Two liquid phases were used. One was organic phase. Another was aqueous phase. By addition of organic phase into the absorption system of CO{sub 2}-aqueous phase, the absorption rate of CO{sub 2} was increased significantly. CO{sub 2} finally accumulated into aqueous phase. The experimental results proved that (1) Absorption rate of carbon dioxide was enhanced by adding organic phase into gas aqueous phase system; (2) Organic phase played the role of transportation of gas solute (CO{sub 2}). Carbon dioxide finally accumulated into aqueous phase.
Date: September 30, 2004
Creator: Hu, Liang
Partner: UNT Libraries Government Documents Department

Engineered Natural Geosorbents for In Situ Immobilization of DNAPLs and Heavy Metals

Description: Extensive subsurface contamination by dense non-aqueous phase liquid (DNAPL) organic solvents and heavy metals is common place at many DOE facilities. Poor performances and excessive costs have made traditional technologies and approaches less than satisfactory for remediation of such sites. It is increasingly apparent that marginal improvements in conventional methods and approaches will not suffice for clean up of many contaminated DOE sites. Innovative approaches using new and/or existing technologies in more efficient and cost-effective ways are thus urgently required.
Date: December 1, 2006
Creator: Weber, Walter J.; Fair, Gordon M. & Boyce, Earnest
Partner: UNT Libraries Government Documents Department