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Syntheses of a New C₂₂H₂₈ Cage Hydrocarbon System and 2,2- Tetramethylene-1 /4-Dibromobutane

Description: (1). An improved method for synthesizing bicyclo (2,2,1) hepta-2,5-diene-7-spiro-1'-cyclopentane (5) has been developed. Thermal reaction of compound (5) with neat iron pentacarbonyl under nitrogen atmosphere affords the corresponding cage dimer (6). Some aspects of the syntheses, spectra, and chemistry of compound (5) and (6) are discussed. (2). A structure isomer of decamethyldodecahedrane (C₃₀H₄₀), molecule (11), is expected to be synthesized via thermal reaction of iron carbonyl complexes with compound (10). An intermediate in this synthesis, 2,2- tetramethylene-1,4-dibromobutane (9) was efficiently synthesized starting from cyclopentanone. Some aspects of the syntheses, spectra, and chemistry of compound (1) to (9) will be discussed.
Date: December 1984
Creator: Wu, An-hsiang
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Synthesis of Anthracyclines Related to Adriamycin

Description: This dissertation reports the preparation of several types of anthraquinones structurally related to adriamycin. It describes the synthesis of two types of 2-aminoquinizarin compounds. It also presents two new syntheses of a heterocyclic tetracyclic ring system, similar to the aglicone ring system of adriamycin. A series of 2-aminoquinizarins was prepared by adding several primary amines to quinizarin. Quinizarin was shown to be essentially inert toward secondary amines. Several secondary amine adducts with quinizarin have been prepared, however, by treating the bis-boroacetate ester of quinizarin with the amines. Both types of 2-aminoquinizarin compounds exhibit outstanding potential for possessing antineoplastic activity, and several have been submitted to the National Cancer Institute for testing in their screening program for antineoplastic agents.
Date: May 1981
Creator: White, Roger J.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Extended Research on Detection of Deception Using Volatile Organic Compound (VOC) Emissions

Description: A system that captures and analyzes volatile organic compound (VOC) emissions from skin surfaces may offer a viable alternative method to the polygraph instrument currently in use for detecting deception in U.S. government settings. Like the involuntary autonomic central nervous system response data gathered during polygraph testing, VOC emissions from the skin may provide data that can be used to detect stress caused by deception. Detecting VOCs, then, may present a noninvasive, non-intrusive method for observing, recording, and quantifying evidence of stress or emotional change.
Date: June 1, 2006
Creator: Studies, Center for Human Reliability
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A low-power pressure-and temperature-programmed separation system for a micro gas chromatograph.

Description: This thesis presents the theory, design, fabrication and testing of the microvalves and columns necessary in a pressure- and temperature-programmed micro gas chromatograph ({micro}GC). Two microcolumn designs are investigated: a bonded Si-glass column having a rectangular cross section and a vapor-deposited silicon oxynitride (Sion) column having a roughly circular cross section. Both microcolumns contain integrated heaters and sensors for rapid, controlled heating. The 3.2 cm x 3.2 cm, 3 m-long silicon-glass column, coated with a non-polar polydimethylsiloxane (PDMS) stationary phase, separates 30 volatile organic compounds (VOCs) in less than 6 min. This is the most efficient micromachined column reported to date, producing greater than 4000 plates/m. The 2.7 mm x 1.4 mm Sion column eliminates the glass sealing plate and silicon substrate using deposited dielectrics and is the lowest power and fastest GC column reported to date; it requires only 11 mW to raise the column temperature by 100 C and has a response time of 11s and natural temperature ramp rate of 580 C/min. A 1 m-long PDMS-coated Sion microcolumn separates 10 VOCs in 52s. A system-based design approach was used for both columns.
Date: October 1, 2006
Creator: Sacks, Richard D. (University of Michigan, Ann Arbor, MI); Robinson, Alex Lockwood (Advanced Sensor Technologies, Albuquerque, NM); Lambertus, Gordon R. (University of Michigan, Ann Arbor, MI); Potkay, Joseph A. (University of Michigan, Ann Arbor, MI) & Wise, Kensall D. (University of Michigan, Ann Arbor, MI)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of hydrocarbon ignition

Description: From Summary: "Accurate spotaneous ignition temperatures have been determined for some 50 pure organic compounds. The effects of a wide variety of additives and of eight selected metals on the spontaneous-ignition-temperature values of representatives of this group also have been observed. Results are correlated with chemical structure and with antiknock characteristics where known; more fundamental aspects of the possible chain-breaking and chain-branching reactions involved are also considered."
Date: January 1952
Creator: Frank, Charles E. & Blackham, Angus U.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Predicting the emission rate of volatile organic compounds from vinyl flooring

Description: A model for predicting the rate at which a volatile organic compound (VOC) is emitted from a diffusion-controlled material is validated for three contaminants (n-pentadecane, n-tetradecane, and phenol) found in vinyl flooring (VF). Model parameters are the initial VOC concentration in the material-phase (C{sub 0}), the material/air partition coefficient (K), and the material-phase diffusion coefficient (D). The model was verified by comparing predicted gas-phase concentrations to data obtained during small-scale chamber tests, and by comparing predicted material-phase concentrations to those measured at the conclusion of the chamber tests. Chamber tests were conducted with the VF placed top side up and bottom side up. With the exception of phenol, and within the limits of experimental precision, the mass of VOCs recovered in the gas phase balances the mass emitted from the material phase. The model parameters (C{sub 0}, K, and D) were measured using procedures that were completely independent of the chamber test. Gas- and material-phase predictions compare well to the bottom-side-up chamber data. The lower emission rates for the top-side-up orientation may be explained by the presence of a low-permeability surface layer. The sink effect of the stainless steel chamber surface was shown to be negligible.
Date: March 1, 2001
Creator: Cox, Steven S.; Little, John C. & Hodgson, Alfred T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of an Experimental Database and Theories for Prediction of Thermodynamic Properties of Aqueous Electrolytes and Nonelectrolytes of Geochemical Significance at Supercritical Temperatures and Pressures

Description: The reactions that cause transformations in organic compounds in the Earth’s crust remain mysterious despite decades of research into how fossil fuel resources form. A major reason for this persistent mysteriousness is the failure of many researchers to realize the intimate involvement of water in those transformations. Our goal was to overcome this staggering ignorance by developing the means to calculate the consequences of reactions involving organic compounds and water. We pursued this research from 1989 through 2006, and this report focuses on progress between 2002 and 2006. There were two major obstacles that we overcame in the course of this research. On the one hand, we developed new theoretical equations that allow researchers to make these calculations. On the other hand, we critiqued available data and provided sound means to make estimates in the absence of experimental data for hundreds of organic compounds dissolved in water. Finally, we merged these two lines of research into an interactive web site that allows users to do the calculations with the equations and data. We call the web site ORCHYD for: “ORganic Compounds HYDration properties database,” but it is far more than a database since it allows users to make extremely accurate predictions of data that may never have been measured. Our progress greatly exceeded our anticipations, and has permitted many new research investigations that were previously impossible. Despite the abrupt termination of funding for this project by the Department of Energy, we are maintaining the web site for the international scientific community. Major research results were published in eleven scientific papers, so they are all in the public domain. Benefits to the public include a new, rigorous, quantitative approach to testing ideas about the fate of organic compounds dissolved in water. These tests can be applied to geochemistry or to industrial …
Date: February 2, 2007
Creator: Shock, Everett L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermodynamic Properties of Organic Compounds. 2. Combustion and Sublimation Enthalpies of 2,4,6-Trimethylbenzonitrile N-Oxide

Description: Article discussing thermodynamic properties of organic compounds and combustion and sublimation enthalpies of 2,4,6-trimethylbenzonitrile N-oxide.
Date: January 1992
Creator: Acree, William E. (William Eugene); Simirsky, Vladimir V.; Kozyro, Alexander A.; Krasulin, Alexander P.; Kabo, Gennady J. & Frenkel, Michael L.
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences
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Modeling the reversible sink effect in response to transient contaminant sources

Description: A physically based diffusion model is used to evaluate the sink effect of diffusion-controlled indoor materials and to predict the transient contaminant concentration in indoor air in response to several time-varying contaminant sources. For simplicity, it is assumed the predominant indoor material is a homogeneous slab, initially free of contaminant, and the air within the room is well mixed. The model enables transient volatile organic compound (VOC) concentrations to be predicted based on the material/air partition coefficient (K) and the material-phase diffusion coefficient (D) of the sink. Model predictions are made for three scenarios, each mimicking a realistic situation in a building. Styrene, phenol, and naphthalene are used as representative VOCs. A styrene butadiene rubber (SBR) backed carpet, vinyl flooring (VF), and a polyurethane foam (PUF) carpet cushion are considered as typical indoor sinks. In scenarios involving a sinusoidal VOC input and a double exponential decaying input, the model predicts the sink has a modest impact for SBR/styrene, but the effect increases for VF/phenol and PUF/naphthalene. In contrast, for an episodic chemical spill, SBR is predicted to reduce the peak styrene concentration considerably. A parametric study reveals for systems involving a large equilibrium constant (K), the kinetic constant (D) will govern the shape of the resulting gas-phase concentration profile. On the other hand, for systems with a relaxed mass transfer resistance, K will dominate the profile.
Date: February 1, 2001
Creator: Zhao, Dongye; Little, John C. & Hodgson, Alfred T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Predicted concentrations in new relocatable classrooms of volatile organic compounds emitted from standard and alternate interior finish materials

Description: Relocatable classrooms (RCs) are widely employed by California school districts to satisfy rapidly expanding space requirements due to population growth and class size reduction policies. There is public concern regarding indoor environmental quality (IEQ) in schools, particularly in RCs, but very little data to support or dispel these concerns. Several studies are investigating various aspects of IEQ in California schools. This laboratory-based study focused on evaluating the emissions of toxic and/or odorous volatile organic compounds (VOCs), including formaldehyde and acetaldehyde, from materials used to finish the interiors of new RCs. Furthermore, the study implemented a procedure for VOC source reduction by testing and selecting lower-emitting materials as substitutes for standard materials. In total, 17 standard and alternate floor coverings, wall panels and ceiling panels were quantitatively tested for emissions of VOCs using smallscale environmental chambers. Working with the largest northern California manufacturer of conventional RCs and two school districts, specifications were developed for four new RCs to be produced in early summer 2001. Two of these will be predominantly finished with standard materials. Alternate carpet systems, an alternate wall panel covering and an alternate ceiling panel were selected for the two other RCs based on the results of the laboratory study and considerations of cost and anticipated performance and maintenance. Particular emphasis was placed on reducing the concentrations of VOCs on California agency lists of toxic compounds. Indoor concentrations of toxic and odorous VOCs were estimated for the four classrooms by mass balance using the measured VOC emission factors, exposed surface areas of the materials in the RCs, and three ventilation rate scenarios. Results indicate that reductions in the concentrations of formaldehyde, acetaldehyde phenol, di(ethylene glycol) butyl ether, vinyl acetate, 1,2,4-trimethylbenzene and 1-methyl-2-pyrrolidinone should be achieved as the result of the source reduction procedure.
Date: July 1, 2001
Creator: Hodgson, Alfred T.; Fisk, William J.; Shendell, Derek G. & Apte, Michael G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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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
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences
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Ferrous Sulfamate Stability in the RA System

Description: Objective: "The observations summarized in the present report were made to determine the stability of ferrous and sulfamate ions and sulfamic acid in RA Column scrub solution (RAS) and in aqueous solution comparable to the RA Column feed tee composition (RAFS). Knowledge of the stability of the reducing agent (ferrous iron) is necessary to properly plan the method of preparation and introduction of this component into the RA system and to assure dependable and reproducible performance."
Date: April 20, 1950
Creator: Clagett, Fred
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Broad Spectrum Catalytic System for Removal of Toxic Organics from Water by Deep Oxidation - Final Report

Description: A most pressing need for the DOE environmental management program is the removal of toxic organic compounds present in groundwater and soil at specific DOE sites. While several remediation procedures have been proposed, they suffer from one or more drawbacks. The objective of the present research was to develop new catalytic procedures for the removal of toxic organic compounds from the environment through their deep oxidation to harmless products. In water, metallic palladium was found to catalyze the deep oxidation of a wide variety of toxic organic compounds by dioxygen at 80-90 C in the presence of carbon monoxide or dihydrogen. Several classes of organic compounds were examined: benzene, phenol and substituted phenols, nitro and halo organics, organophosphorus, and organosulfur compounds. In every case, deep oxidation to carbon monoxide, carbon dioxide, and water occurred in high yields, resulting in up to several hundred turnovers over a 24 hour period. For substrates susceptible to hydrogenation, the conversions were generally high with dihydrogen than with carbon monoxide. It is clear from the results obtained that we have discovered an exceptionally versatile catalytic system for the deep oxidation of toxic organic compounds in water. This system possesses several attractive features not found simultaneously in other reported systems. These are (a) the ability to directly utilize dioxygen as the oxidant, (b) the ability to carry out the deep oxidation of a particularly wide range of functional organics, and (c) the ease of recovery of the catalyst by simple filtration.
Date: December 1, 2000
Creator: Sen, Ayusman
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Phase Stability of Homogeneous Reactor Hot Fuel Solutions

Description: S>Portions of two samples of HRT fael solutions were sealed in silica capillary tubes approximately three weeks after they were removed from the reactor and the temperature at which each solution separated into two liquid layers was determined. The values found, 325 er inch per 1 C for one sample and 326 er inch per 1/2 C for the other, are slightly lower than predicted from experiments with synthetic fuel solutions (329--330 C) but the discrepancies are small enough so that they could be accounted for by the minor differences in composition between the synthetic and reactor fuel solutions. There appears to be little reason to believe that the high radiation level which the fuel- solution is exposed to in the reactor has a significant effect on its phase behavior, at least after it has cooled to 2r per ml. Dilution of fuel solution wvith 8 vol.% of 30% H/sub 2/O/sub 2/ and with the same amount of H/sub 2/O increased the two-liquid phase formation temperature about 2 EC but increasing the free D/sub 2/SO/sub 2/ concentration from about 0.017 to 0.04 M raised the immiscibility temperature 19 to 345 C. (auth)
Date: August 18, 1959
Creator: Barton, C. J.; Gill, J. S.; Habert, G. M.; Marshall, W. L. & Moore, R. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Partition Coefficients of Organic Compounds in New Imidazolium and Tetralkylammonium Based Ionic Liquids Using Inverse Gas Chromatography

Description: This article discusses partition coefficients of organic compounds in new imidazolium and tetralkylammonium based ionic liquids using inverse gas chromatography.
Date: September 11, 2009
Creator: Mutelet, Fabrice; Revelli, Anne-Laure; Jaubert, Jean-Noël; Sprunger, Laura M.; Baker, Gary A. & Acree, William E. (William Eugene)
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences
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Thermodynamic Properties of Organic Compounds. 3. Sublimation Enthalpy and Heat Capacities of 2,4,6-Trimethylbenzonitrile N-oxide

Description: Article discussing thermodynamic properties of organic compounds and sublimation enthalpy and heat capacities of 2,4,6-trimethylbenzonitrile N-oxide.
Date: January 1993
Creator: Acree, William E. (William Eugene); Sevruk, Viktor M.; Kozyro, Alexander A.; Krasulin, Alexander P.; Kabo, Gennady J. & Frenkel, Michael L.
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences
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Silenes and Silenoids in the Chemistry of Cyclopentadienylsilanes

Description: Evidence is presented that apparent silene products obtained from the metalation of cyclopentadienyldimethyl - chlorosilane either with tert-butyl1ithium or with methylenetriphenylphosphorane actually arise from the metalated starting material, a silenoid, rather than from a silafulvene intermediate. Trimethylmethoxysi1ane is shown to be an effective trap for dimethylsilafulvene. A new dimethylsilafulvene precursor, bis(dimethylmethoxysi1yl) cyclopentadiene, which gives high yields of dimethyldimethoxysi1ane and the silafulvene at temperatures as low as 240°C is reported.
Date: August 1986
Creator: Rozell, James M. (James Morris)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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A General Treatment of Solubility. 1. The QSPR Correlation of Solvation Free Energies of Single Solutes in Series of Solvents

Description: Article on a general treatment of solubility and the quantitative structure-property relationship (QSPR) correlation of solvation free energies of single solutes in series of solvents.
Date: October 2, 2003
Creator: Katritzky, Alan R.; Oliferenko, Alexander A.; Oliferenko, Polina V.; Petrukhin, Ruslan; Tatham, Douglas B.; Maran, Uko, 1966- et al.
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences
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