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Combined Electrochemistry and Spectroscopy of Complexes and Supramolecules containing Bipyridyl and Other Azabiphenyl Building Blocks

Description: A group of azabiphenyl complexes and supramolecules, and their reduced and oxidized forms when possible, were characterized by cyclic voltammetry and electronic absorption spectroscopy. The oxidized and reduced species, if sufficiently stable, were further generated electrochemically inside a specially designed quartz cell with optically transparent electrode, so that the spectra of the electrochemically generated species could be taken in situ. Assignments were proposed for both parent and product electronic spectra. Species investigated included a range of Ru(II) and Pt(II) complexes, as well as catenanes and their comparents. Using the localized electronic model, the electrochemical reduction can be in most cases assigned as azabiphenyl-based, and the oxidation as transition metal-based. This is consistent with the fact that the azabiphenyl compounds have a low lying π* orbital. The electronic absorption spectra of the compounds under study are mainly composed of π —> π* bands with, in some cases, charge transfer bands also.
Date: August 1995
Creator: Yang, Lei
Partner: UNT Libraries

Engineering Properties of Diphenyl

Description: Report issued by the Argonne National Laboratory discussing engineering properties of diphenyl. As stated in the abstract, "data collected from the literature on the vapor pressure, enthalpy, liquid density, and vapor density of pure diphenyl are presented. A Mollier diagram, a temperature entropy diagram, and data on viscosity of diphenyl as a function of temperature are also presented" (p. 5). This report includes tables, and illustrations.
Date: August 11, 1953
Creator: Anderson, Kermit
Partner: UNT Libraries Government Documents Department

Dipole Moments of Diphenyl Compounds with Conjugated Double Bonds

Description: This thesis is a continuation of a study of molecular moments begun by Joseph T. Fielder. In his paper he discussed the theory and the equipment necessary for such a study. It is the purpose of this paper to set forth modifications of his equipment, to present data obtained with this modified equipment, and to interpret this data.
Date: 1950
Creator: Spalding, Dan W.
Partner: UNT Libraries

Heat Capacity Uncertainty Calculation for the Eutectic Mixture of Biphenyl/Diphenyl Ether Used as Heat Transfer Fluid: Preprint

Description: The main objective of this study was to calculate the uncertainty at 95% confidence for the experimental values of heat capacity of the eutectic mixture of biphenyl/diphenyl ether (Therminol VP-1) determined from 300 to 370 degrees C. Twenty-five samples were evaluated using differential scanning calorimetry (DSC) to obtain the sample heat flow as a function of temperature. The ASTM E-1269-05 standard was used to determine the heat capacity using DSC evaluations. High-pressure crucibles were employed to contain the sample in the liquid state without vaporizing. Sample handling has a significant impact on the random uncertainty. It was determined that the fluid is difficult to handle, and a high variability of the data was produced. The heat capacity of Therminol VP-1 between 300 and 370 degrees C was measured to be equal to 0.0025T+0.8672 with an uncertainty of +/- 0.074 J/g.K (3.09%) at 95% confidence with T (temperature) in Kelvin.
Date: September 1, 2012
Creator: Gomez, J. C.; Glatzmaier, G. C. & Mehos, M.
Partner: UNT Libraries Government Documents Department

DESTRUCTION OF TETRAPHENYLBORATE IN TANK 48H USING WET AIR OXIDATION BATCH BENCH SCALE AUTOCLAVE TESTING WITH ACTUAL RADIOACTIVE TANK 48H WASTE

Description: Wet Air Oxidation (WAO) is one of the two technologies being considered for the destruction of Tetraphenylborate (TPB) in Tank 48H. Batch bench-scale autoclave testing with radioactive (actual) Tank 48H waste is among the tests required in the WAO Technology Maturation Plan. The goal of the autoclave testing is to validate that the simulant being used for extensive WAO vendor testing adequately represents the Tank 48H waste. The test objective was to demonstrate comparable test results when running simulated waste and real waste under similar test conditions. Specifically: (1) Confirm the TPB destruction efficiency and rate (same reaction times) obtained from comparable simulant tests, (2) Determine the destruction efficiency of other organics including biphenyl, (3) Identify and quantify the reaction byproducts, and (4) Determine off-gas composition. Batch bench-scale stirred autoclave tests were conducted with simulated and actual Tank 48H wastes at SRNL. Experimental conditions were chosen based on continuous-flow pilot-scale simulant testing performed at Siemens Water Technologies Corporation (SWT) in Rothschild, Wisconsin. The following items were demonstrated as a result of this testing. (1) Tetraphenylborate was destroyed to below detection limits during the 1-hour reaction time at 280 C. Destruction efficiency of TPB was > 99.997%. (2) Other organics (TPB associated compounds), except biphenyl, were destroyed to below their respective detection limits. Biphenyl was partially destroyed in the process, mainly due to its propensity to reside in the vapor phase during the WAO reaction. Biphenyl is expected to be removed in the gas phase during the actual process, which is a continuous-flow system. (3) Reaction byproducts, remnants of MST, and the PUREX sludge, were characterized in this work. Radioactive species, such as Pu, Sr-90 and Cs-137 were quantified in the filtrate and slurry samples. Notably, Cs-137, boron and potassium were shown as soluble as a result of the WAO reaction. ...
Date: March 31, 2009
Creator: Adu-Wusu, K & Paul Burket, P
Partner: UNT Libraries Government Documents Department

Microporous Metal Organic Materials for Hydrogen Storage

Description: We have examined a number of Metal Organic Framework Materials for their potential in hydrogen storage applications. Results obtained in this study may, in general, be summarized as follows: (1) We have identified a new family of porous metal organic framework materials with the compositions M (bdc) (ted){sub 0.5}, {l_brace}M = Zn or Co, bdc = biphenyl dicarboxylate and ted = triethylene diamine{r_brace} that adsorb large quantities of hydrogen ({approx}4.6 wt%) at 77 K and a hydrogen pressure of 50 atm. The modeling performed on these materials agree reasonably well with the experimental results. (2) In some instances, such as in Y{sub 2}(sdba){sub 3}, even though the modeling predicted the possibility of hydrogen adsorption (although only small quantities, {approx}1.2 wt%, 77 K, 50 atm. hydrogen), our experiments indicate that the sample does not adsorb any hydrogen. This may be related to the fact that the pores are extremely small or may be attributed to the lack of proper activation process. (3) Some samples such as Zn (tbip) (tbip = 5-tert butyl isophthalate) exhibit hysteresis characteristics in hydrogen sorption between adsorption and desorption runs. Modeling studies on this sample show good agreement with the desorption behavior. It is necessary to conduct additional studies to fully understand this behavior. (4) Molecular simulations have demonstrated the need to enhance the solid-fluid potential of interaction in order to achieve much higher adsorption amounts at room temperature. We speculate that this may be accomplished through incorporation of light transition metals, such as titanium and scandium, into the metal organic framework materials.
Date: November 30, 2008
Creator: Sankar, S. G.; Li, Jing & Johnson, Karl
Partner: UNT Libraries Government Documents Department

ORGANIC COOLANT RECLAMATION. Quarterly Progress Report No. 3 for June 15, 1959-September 15, 1959

Description: In the third quarter of research on organic coolant reclamation, reaction conditions which show promise as reclamation prccedures were found in two major areas of investigation. In the study of hydrocracking of polyphenyls, ten catalysts show activity. One of these, a platinum on alumina, gives a very clean reaction with high conversions per pass and high yields in the model systems under study. The redistribution reaction in the model case of benzene and p-terphenyl gave reproducible results with high enough conversion to be of interest for reclamation. ( For preceding period see AECU-4268.) (auth)
Date: October 15, 1959
Creator: Wineman, R.J.; Adams, J.S. & Scola, D.A.
Partner: UNT Libraries Government Documents Department

Rigid molecular foams

Description: This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Organic analogues to inorganic zeolites would be a significant step forward in engineered porous materials and would provide advantages in range, selectivity, tailorability, and processing. Rigid molecular foams or {open_quotes}organic zeolites{close_quotes} would not be crystalline materials and could be tailored over a broader range of pore sizes and volumes. A novel process for preparing hypercrosslinked polymeric foams has been developed via a Friedel-Crafts polycondensation reaction. A series of rigid hypercrosslinked foams have been prepared using simple rigid polyaromatic hydrocarbons including benzene, biphenyl, m-terphenyl, diphenylmethane, and polystyrene, with dichloroxylene (DCX) as the pore size. After drying the foams are robust and rigid. Densities of the resulting foams can range from 0.15 g/cc to 0.75 g/cc. Nitrogen adsorption studies have shown that by judiciously selecting monomers and the crosslinking agent along with the level of crosslinking and the cure time of the resulting gel, the pore size, pore size distribution, and the total surface area of the foam can be tailored. Surface areas range from 160 to 1,200 m{sup 2}/g with pore sizes ranging from 6 {angstrom} to 2,000 {angstrom}.
Date: December 31, 1998
Creator: Steckle, W.P. Jr.; Mitchell, M.A. & Aspen, P.G.
Partner: UNT Libraries Government Documents Department

Solvent reorganization energies measured by an electron transfer reaction in supercritical ethane.

Description: The intermolecular electron transfer reaction between a biphenyl anion and pyrene in supercritical ethane was studied using pulse radiolysis. Second-order electron transfer rates were found to be of the order of 10{sup 11} M{sup {minus}1} s{sup {minus}1}. The rate constants appear to be approximately constant over the pressure range 55-133 bar. Two possibilities are discussed that could explain the present results: solvent clustering; or a dependence of the solvent reorganization energy on pressure. Reorganization energies E{sub r} of non-polar supercritical ethane were estimated from the observed rate constant using the modified Marcus equation. E{sub r} may be larger than normally expected for non-polar solvents because of density fluctuations.
Date: April 14, 1997
Creator: Feng, W.; Jonah, C. D.; Sawamura, S. & Takahashi, K.
Partner: UNT Libraries Government Documents Department

Model compound study of the pathways for aromatic hydrocarbon formation in soot.

Description: To explore the mechanisms for formation of aromatic hydrocarbons as precursors to soot, a model system using combustion of biphenyl in a fuel rich flame is studied. The soots acquired at three different temperatures are solvent extracted and the extract characterized by both GCMS and high resolution mass spectrometry. A description of the NMR results for the whole soots has been published (1). The production of most products could be rationalized from the coupling of biphenyls and subsequent aromatic species and the addition of acetylenes to existing aromatic molecules. Early work by Badger on pyrolysis of hydrocarbons is used in developing these schemes (2). The reaction schemes to produce larger aromatic hydrocarbons will be discussed. Richter and Howard have discussed in detail potential reaction mechanisms in the formation of aromatics as precursors to soot (3).
Date: April 29, 2002
Creator: Tomczyk, N. A.; Hunt, J. E.; Winans, R. E.; Solum, M. S.; Pugmire, R. J. & Fletcher, T. H.
Partner: UNT Libraries Government Documents Department

Implementation of DOWTHERM A Properties into RELAP5-3D/ATHENA

Description: DOWTHERM A oil is being considered for use as a heat transfer fluid in experiments to help in the design of heat transfer components for the Next Generation Nuclear Plant (NGNP). In conjection with the experiments RELAP5-3D/ATHENA will be used to help design and analyzed the data generated by the experiments. Inorder to use RELAP5-3D the thermophysical properties of DOWTHERM A were implemented into the fluids package of the RELAP5-3D/ATHENA computer propgram. DOWTHERM A properties were implemented in RELAP5-3D/ATHENA using thermophysical property data obtain from a Dow Chemical Company brochure. The data were curve fit and the polynomial equations developed for each required property were input into a fluid property generator. The generated data was then compared to the orginal DOWTHERM A data to verify that the fluid property data generated by the RELAP5-3D/ATHENA code was representitive of the original input data to the generator.
Date: April 1, 2010
Creator: Moore, Richard L.
Partner: UNT Libraries Government Documents Department

IUPAC-NIST Solubility Data Series. 98. Solubility of Polycyclic Aromatic Hydrocarbons in Pure and Organic Solvent Mixtures-Revised and Updated. Part 3. Neat Organic Solvents

Description: Article on the solubility of polycyclic aromatic hydrocarbons in pure and organic solvent mixtures. This work updates volumes 54, 58, and 59 in the IUPAC Solubility Data Series and presents solubility data for polycyclic aromatic hydrocarbon solutes dissolved in neat organic solvents.
Date: March 4, 2013
Creator: Acree, William E. (William Eugene)
Partner: UNT College of Arts and Sciences

Precipitate hydrolysis experimental facility (PHEF) Run 66 And 67, Final report

Description: During the period from late June to early September of this year, approximately 1,600 gallons of precipitate feed stored in the Precipitate Hold Tank (PHT) at PHEF decomposed. This decomposition took place during a two month storage period of the Tetraphenyl borate (TPB) precipitate under a CO{sub 2} blanket. The visual inspection of the tank revealed that a very small amount of TPB solids were left and that there were approximately 100 to 110 gals of benzene/high boilers present in the tank. The resultant decomposition products in the PHT consist of an organic and aqueous phase containing a small quantity of unreacted solids. A path forward was developed to understand TPB decomposition and to determine if the material remaining in the PHT could be processed without adverse effects to the process or equipment. A small scale hydrolysis run with the remaining PHT material was made by Process Technology Development Group of DWPT at TNX. It was determined from small scale runs and an extensive analysis of the PHT material that the decomposed material was safe to run at PHEF without adversely affecting the process or equipment. The PHT volume was 1,592 gallons at the time of decomposition. Two runs (66 and 67) were performed to process the decomposed feed. The main objective of these runs was to process the decomposed precipitate from the PHT. In both the runs copper nitrate was used as the catalyst. Because of the decomposition, the effectiveness of the copper nitrate in catalyzing the destruction of TPB could not be completed. The significant findings of Run 66 are: (1) after 5 hours of aqueous boil, the aqueous product had a Diphenylamine (DPA) concentration of 31 mg/L and the Biphenyl concentration of 8 mg/L. At these concentrations, the high boiling organic mass in the aqueous product included ...
Date: February 11, 2000
Creator: Shah, H. B. & Lambert, D. P.
Partner: UNT Libraries Government Documents Department

Analysis of PAH and PCB Emissions from the Combustion of dRDF and the Nondestructive Analysis of Stamp Adhesives

Description: This work includes two unrelated areas of research. The first portion of this work involved combusting densified refuse derived fuel (dRDF) with coal and studying the effect that Ca(0H)2 binder had on reducing polycyclic aromatic hydrocarbon (PAH) and polychlorinated biphenyl (PCB) emissions. The second area of work was directed at developing nondestructive infrared techniques in order to aid in the analysis of postage stamp adhesives. With Americans generating 150-200 million tons a year of Municipal Solid Waste (MSW) and disposing of nearly ninety percent of it in landfills, it is easy to understand why American landfills are approaching capacity. One alternative to landfilling is to process the MSW into RDF. There are technical and environmental problems associated with RDF. This work provides some answers concerning the amount of PAH and PCB emissions generated via the combustion of RDF with coal. It was found that the Ca(OH)2 binder greatly reduced both the PAH and the PCB emissions. In fact, PAH emissions at the ten-percent level were reduced more by using the binder than by the pollution control equipment. If the Ca(0H)2 binder can reduce not only PAH and PCB emissions, but also other noxious emissions, such as acid gases or dioxin, RDF technology could soon be the answer to the current landfill problems. The second portion of this work focused on developing a method to analyze stamp adhesives nondestructively. Using this method, it was fairly easy to differentiate among the three different types of adhesives that have been used by the United States Postal Service: gum arabic, dextrin, and polyvinyl alcohol. Differences caused by changes in chemicals added to the adhesives were also detected. Also, forgeries were detected with as much success, if not more, than by conventional methods. This work also led to the construction of equipment that allows large ...
Date: May 1989
Creator: Poslusny, Matthew
Partner: UNT Libraries

A NOVEL APPROACH TO CATALYTIC DESULFURIZATION OF COAL

Description: Column chromatographic separation of the S=PBu{sub 3}/PBu{sub 3} product mixture followed by weighing the S=PBu{sub 3}, and by vacuum distillation of S=PBu{sub 3}/PBu{sub 3}mixture followed by gas chromatographic analysis are described. Effects of coal mesh size, pre-treatment with methanol Coal (S) + excess PR{sub 3} {yields} Coal + S=PR{sub 3}/PBu{sub 3} and sonication on sulfur removal by PBu{sub 3} revealed that particle size was not observed to affect desulfurization efficiency in a consistent manner. Coal pretreatment with methanol to induce swelling or the addition of a filter aid such as Celite reduced desulfurization efficiency of the PBu{sub 3} and sonication was no more effective than heating. A rationale is put forth for the lack of efficacy of methanol pretreatment of the coal in desulfurization runs with PBu{sub 3}. Coal desulfurization with PBu{sub 3} was not improved in the presence of miniscule beads of molten lithium or sodium as a desulfurizing reagent for SPBu{sub 3} in a strategy aimed at regenerating PBu{sub 3} inside coal pores. Although desulfurization of coals did occur in sodium solutions in liquid ammonia, substantial loss of coal mass was also observed. Of particular concern is the mass balance in the above reaction, a problem which is described in some detail. In an effort to solve this difficulty, a specially designed apparatus is described which we believe can solve this problem reasonably effectively. Elemental sodium was found to remove sulfur quantitatively from a variety of polycyclic organosulfur compounds including dibenzothiophene and benzothiophene under relatively mild conditions (150 C) in a hydrocarbon solvent without requiring the addition of a hydrogen donor. Lithium facilitates the same reaction at a higher temperature (254 C). Mechanistic pathways are proposed for these transformations. Curiously, dibenzothiophene and its corresponding sulfone was virtually quantitatively desulfurized in sodium solutions in liquid ammonia at -33 C, ...
Date: November 1, 2001
Creator: Verkade, John G.
Partner: UNT Libraries Government Documents Department