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Summary of the Research Progress Meeting

Description: This report discusses progress on the following topics: (1) some new isotopes in the rare earth region; (2) remarks on a new alpha series; (3) solid counters; (4) naphthalene crystals have been replaced with anthracite in one of the experimental counters and some excellent results are obtained; and (5) biological experiments with the deuteron bean of the 184-inch cyclotron.
Date: April 8, 1948
Creator: Wakerling, R.K.
Partner: UNT Libraries Government Documents Department

Functional Neural Toxicity and Endocrine Responses in Mice Following Naphthalene Exposure

Description: Polycyclic aromatic hydrocarbons (PAHs) are a well studied and diverse class of environmental toxicants. PAHs act via the aryl hydrocarbon receptor (AhR), and studies have suggested that PAHs may elicit neurological and estrogenic effects. Doses of PAHs between 50 to 150 ppm may elicit neurotoxicity in rodent models. The present study investigated the effects of naphthalene on in vivo steroidogenesis in Swiss Webster male mice, and in vitro neural function of Balb-C/ICR mice frontal cortex neurons. These data suggest that naphthalene may not elicit steroidogenic effects at concentrations ranging from 0.2 to 25 mg/kg/day, following a 7 day subcutaneous dosing regime. In addition, naphthalene may cause functional toxicity of frontal cortex neurons at concentrations of 32 to 160 ppm naphthalene.
Date: August 2010
Creator: Colbert, Crystal
Partner: UNT Libraries

Design and Formation of a Large, Tetrahedral, Metal-ligand Cluster Using 1,1'-Binaphthyl Ligands

Description: Many chemists have been fascinated with the development of discrete supramolecular structures that encapsulate guest molecules. These structures can be assembled through covalent or hydrogen bonds, electrostatic or metal-ligand interactions. These host structures have provided valuable insight into the forces involved in small molecule recognition. Our work has focused on the design and study of metal-ligand clusters of varying sizes. The naphthalene [M{sub 4}L{sub 6}]{sup 12-} cluster 1, shown in Figure 1, has demonstrated diastereoselective guest binding and chiral induction properties as well as the ability to catalyze reactions carried out inside the cavity in an enzyme-like manner. However, the size of the cavity (ca. 300-500 {angstrom}{sup 3}) has often limited the scope of substrates for these transformations.
Date: March 13, 2008
Creator: Biros, Shannon M.; Yeh, Robert M. & Raymond, Kenneth N.
Partner: UNT Libraries Government Documents Department

Alternative Donor--Acceptor Stacks from Crown Ethers and Naphthalene Diimide Derivatives: Rapid, Selective Formation from Solution and Solid State Grinding

Description: Self assembling {pi}-conjugated molecules into ordered structures are of increasing interest in the field of organic electronics. One particular example is charge transfer complexes containing columnar alternative donor-acceptor (ADA) stacks, where neutral and ionic ground states can be readily tuned to modulate electrical, optical, and ferroelectrical properties. Aromatic-aromatic and charge transfer interactions have been the leading driving forces in assisting the self-assembly of ADA stacks. Various folding structures containing ADA stacks were assembled in solution with the aid of solvophobic or ion-binding interactions. Meanwhile, examples of solid ADA stacks, which are more appealing for practical use in devices, were obtained from cocrystalization of binary components or mesophase assembly of liquid crystals in bulk blends. Regardless of these examples, faster and more controllable approaches towards precise supramolecular order in the solid state are still highly desirable.
Date: January 22, 2009
Creator: Lawrence Berkeley National Laboratory. Advanced Light Source.
Partner: UNT Libraries Government Documents Department

Hydrous pyrolysis of pole treating chemicals: (a) initital measurement of hydrous pyrolysis rates for napthalene and pentachlorophenol; (b) solubility of flourene at temperatures up to 150{degrees}C

Description: The temperature dependencies of the hydrous pyrolysis/oxidation (HPO) aqueous phase oxidation reactions of naphthalene and pentachlorophenol have been determined for phosphate buffered systems using Dickson-type reaction vessels. The HPO experimental temperatures ranged from 114{degrees}C to 148{degrees}C for naphthalene and 114{degrees}C to 137{degrees}C for pentachlorophenol. The loss of the organic species was used to determine activation energies of 95.8 kJ/mole for naphthalene oxidation and 84.8 kJ/mole for pentachlorophenol oxidation. Aqueous concentrations of target compounds and reaction intermediates were determined by gas chromatography and compound identification was verified by gas chromatography - mass spectrometry. During the experiments the pollutants were completely mineralized, as indicated by a stoichiometric production of inorganic carbon in the case of naphthalene and inorganic carbon and chloride in the case of pentachlorophenol. HPO of pentachlorophenol produced 2,3,5,6- tetrachlorophenol as an intermediate, whereas no intermediates amenable by GC were observed during the HPO of naphthalene. Measurements of the aqueous solubility of florin in an unbuffered solution have been made covering the temperature range from 20{degrees}C to 150{degrees}C. There is very good agreement between this data set and data previously published covering the lower temperature range (20{degrees}C to 75{degrees}C). Extension of the solubility measurements to higher temperatures covers the in situ temperatures achievable during field application of HPO and demonstrated a nearly exponential rise in aqueous solubility as a function of temperature, with a 10 fold increase in aqueous florin solubility going from 75{degrees}C to 125{degrees}C and a 20 fold increase in going from 75{degrees}C to 150{degrees}C.
Date: November 15, 1997
Creator: Leif, R. N., LLNL
Partner: UNT Libraries Government Documents Department

Determination of Biotransformation and Biodegradation Rate Constants for Naphthalene, Lindane and Phenol

Description: Biotransformation and biodegradation rate constants were determined for naphthalene, lindane, and phenol in water samples from three different sources. Rate constants produced from monitoring disappearance of the parent chemical (biotransformation) were compared to those obtained from mineralization of the chemical (ultimate biodegradation) by ¹⁴CO₂ evolution as well as acidification of the residual ¹⁴C-labeled compound (primary biodegradation). Rate constants were statistically different for the three chemicals. The water source affected the rate constants. When biomass measurements of the waters were considered and second-order rate constants were derived, there was no statistical evidence that this parameter gave a reliable rate constant statistic that could be useful in predicting the fate of any of naphthalene, lindane, and phenol in these waters.
Date: December 1981
Creator: Crawford, Judith Chase
Partner: UNT Libraries

IDENTIFICATION OF HYDROCARBON TYPES IN "ULTRASENE"

Description: The C/sup 1//sup 1/-C/sup 1//sup 4/ components of a sample of"Ultrasene" were identified as normal- and iso-paraffins; mono-, bi-, and tri-cycloparaffins; alkylbenzenes; indans; indenes; naphthalenes; and acenaphthenes. The aromatic content of this sample was 3.0 vol%. (auth)
Date: April 1, 1961
Creator: Wilhite, R. N.
Partner: UNT Libraries Government Documents Department

The Stereochemistry of 1,4-Di-Tert-Butyl-1,4-Dihydronaphthalene

Description: A new approach was taken in the elucidation of the stereochemistry of the symmetrically 1,4-disubstituted 1,4-dihydronaphthalene systems which show deceptively simple NMR spectra. Thus, the stereochemistry of 1,4-di-tert-butyl-1,4-dihydronaphthalene was established unequivocally. The epoxide derivative, the subject compound, 1,4-di-tertbutyl-2, 3-epoxy-1, 4-dihydronaphthalene, was formed and its trans stereochemistry was established by ¹H NMR and ¹³C NMR. A lanthanide shift study was also conducted on the epoxide derivative, further proving the trans stereochemistry. One of the lanthanide shifted spectra was analyzed using the LAACOON III computer program and the true coupling constants obtained this way were in excellent agreement with the experimental spectrum. Establishing the trans stereochemistry of the epoxide derivative proved the trans stereochemistry of 1,4-di-tert-butyl-1,4-dihydronaphthalene.
Date: December 1980
Creator: McDaniel, Oya A.
Partner: UNT Libraries

Low severity coal liquefaction promoted by cyclic olefins. Quarterly report, October 1996--December 1996

Description: The goal of this research is to develop a methodology for analyzing the reactivity of cyclic olefins in situ in a high temperature and high pressure infrared cell. The reactivities of naphthalene, decalin, tetralin, isotetralin, 1,2-dihydronaphthalene and 1,4-dihydronaphthalene have been studied at 230{degrees}C under ambient pressure and under 500 psig blankets of both nitrogen and hydrogen.
Date: June 1, 1997
Creator: Curtis, C.W.
Partner: UNT Libraries Government Documents Department

Multiphoton ionization of ions, neutrals, and clusters. Progress report

Description: Scientific results are summarized from a three year research program on multiphoton ionization in aromatic molecules, clusters, and their ions. As originally proposed, the studies elucidated a new cluster ionization mechanism, characterized properties of long range intermolecular interactions, and investigated electronic transitions of aromatic cations cooled in a supersonic beam. The studies indicate that the new cluster ionization mechanism is highly efficient and dominates conventional 1 + 1 resonant ionization. In the case of the dimer of the large aromatic molecule fluorene, the results suggest that excimer formation competes with a direct ionization process. Highly selective excitonic spectra have been identified for several cluster species.
Date: June 28, 1991
Creator: Wessel, J.
Partner: UNT Libraries Government Documents Department

Molecular detection using Rydberg, autoionizing, and cluster states. Progress report

Description: The author reports on investigations of multiphoton ionization spectroscopy in pure clusters of aromatic molecules and mixed clusters of an aromatic molecule with a rare gas atom. Conditions needed for efficient production of ion clusters are discussed. Experimental results that establish geometry of naphthalene and benzene clusters are described.
Date: August 15, 1990
Creator: Wessel, J.
Partner: UNT Libraries Government Documents Department

Molecular detection using Rydberg, autoionizing, and cluster states. Progress report

Description: Continuing investigations of multiphoton ionization processes in naphthalene have established the geometry and spectroscopy of trimer and tetramer cluster states. A new, highly efficient ionization mechanism has been identified in the trimer. It is closely related to autoionization of 2-electron atoms by resonant 2-photon excitation and to exciton fusion in larger clusters.
Date: August 17, 1989
Creator: Wessel, J.
Partner: UNT Libraries Government Documents Department

Caustic-Side Solvent Extraction: Anti-Caking Surfactants Found to be Cause of Apparent Effect of High Nitrite Concentration on Cesium Stripping

Description: Experiments conducted in FY01 previously indicated a potential cesium stripping problem in the CSSX process due to the presence of nitrite in the waste simulant. The stripping issue seemed all the more important as the nitrite concentration increased. Experiments presented in this work have demonstrated that the true reason for the cesium stripping problem was in fact the presence of an anti-caking agent in the,sodium nitrite. used for the preparation of the simulants. The anti-caking agent is actually a mixture of well-known surfactants, sodium mono- and di-methyl naphthalene sulfonate that can partition into the organic-phase on extraction, then retain cesium upon stripping. The effect was demonstrated by adding known amounts of the anti-caking agent to clean systems. Data suggest that rejuvenation of the solvent can be obtained by a caustic wash following the stripping stage.
Date: June 13, 2002
Creator: Delmau, L.H.
Partner: UNT Libraries Government Documents Department

Evidence of gating in hundred nanometer diameter pores: an experimental and theoretical study

Description: We report on the observation of an unexpected gating mechanism at the 100 nm scale on track-etched polycarbonate membranes. Transport measurements of methyl viologen performed by absorption spectroscopy under various pH conditions demonstrated that perfect gating was achieved for 100 nm diameter pores at pH 2, while the positively charged molecular ions moved through the membrane according to diffusion laws at pH 5. An oppositely charged molecular ion, naphthalene disulfonate, in the same membrane, showed the opposite trend: diffusion of the negative ion at pH 2 and perfect gating at pH 5. The influence of parameters such as ionic strength and membrane surface coating were also investigated. A theoretical study of the system shows that at this larger length scale the magnitude of the electric field in the vicinity of the pores is too small to account for the experimental observations, rather, it is the surface trapping of the mobile ion (Cl{sup -} or Na{sup +}) which gives rise to the gating phenomena. This surprising effect might have potential applications for high-throughput separation of large molecules and bio-organisms.
Date: January 11, 2006
Creator: Letant, S E; Schaldach, C M; Johnson, M R; Sawvel, A; Bourcier, W L & Wilson, W D
Partner: UNT Libraries Government Documents Department

Hazard Assessment of Chemical Air Contaminants Measured in Residences

Description: Identifying air pollutants that pose a potential hazard indoors can facilitate exposure mitigation. In this study, we compiled summary results from 77 published studies reporting measurements of chemical pollutants in residences in the United States and in countries with similar lifestyles. These data were used to calculate representative mid-range and upper bound concentrations relevant to chronic exposures for 267 pollutants and representative peak concentrations relevant to acute exposures for 5 activity-associated pollutants. Representative concentrations are compared to available chronic and acute health standards for 97 pollutants. Fifteen pollutants appear to exceed chronic health standards in a large fraction of homes. Nine other pollutants are identified as potential chronic health hazards in a substantial minority of homes and an additional nine are identified as potential hazards in a very small percentage of homes. Nine pollutants are identified as priority hazards based on the robustness of measured concentration data and the fraction of residences that appear to be impacted: acetaldehyde; acrolein; benzene; 1,3-butadiene; 1,4-dichlorobenzene; formaldehyde; naphthalene; nitrogen dioxide; and PM{sub 2.5}. Activity-based emissions are shown to pose potential acute health hazards for PM{sub 2.5}, formaldehyde, CO, chloroform, and NO{sub 2}.
Date: May 10, 2010
Creator: Logue, J.M.; McKone, T.E.; Sherman, M. H. & Singer, B.C.
Partner: UNT Libraries Government Documents Department

Molecular catalytic coal liquid conversion. Quarterly report, [October--December 1994]

Description: In this Quarter, the research was focused on the two general tasks: Task 1, molecular organometallic catalysts and the Task 2, organic base-catalyzed arene hydrogenation and hydrotreating of the coal liquids. With regards to Task 1, a biphase catalyst system, [1.5-HDRhC1]2/Buffer, was investigated for the hydrogenation of tetralin to decalin under the condition of atmosphere H2 and room temperature. The primary results indicate that tetralin was hydrogenated to decalin in more that 91% yield when only 0.5 mole% of catalyst was used. The major product was trans decalin and the cis/trans isomer ratio is 4-6: 1. The reaction was influenced by variety of the reaction conditions such as solvents used, the organic phase/aqueous phase ratio, etc. Task 2 was focused on the Catalyst 2-catalyst hydrogenation of other polycondensed aromatic hydrocarbons and on the hydrotreating of the coal liquids catalyzed by Catalyst 2 system under the similar conditions. Besides naphthalene as described in the last Quarter`s report, other polycondensed aromatic hydrocarbons such as anthracene, acridine as well as 1-methoxynaphthalene were hydrogenated in good yields. Coal liquids can be hydrogenated catalyzed by Catalyst 2 include monocyclic aromatic hydrocarbons.
Date: December 31, 1994
Creator: Stock, L.M. & Yang, Shiyong
Partner: UNT Libraries Government Documents Department

Reaction mechanisms in aromatic hydrocarbon formation involving the C{sub 5}H{sub 5} cyclopentadienyl moiety

Description: The quantum chemical BAC-MP4 and BAC-MP2 methods have been used to investigate the reaction mechanisms leading to polycyclic aromatic hydrocarbon (PAH) ring formation. In particular the authors have determined the elementary reaction steps in the conversion of two cyclopentadienyl radicals to naphthalene. This reaction mechanism is shown to be an extension of the mechanism occurring in the H atom-assisted conversion of fulvene to benzene. The net reaction involves the formation of dihydrofulvalene, which eliminates a hydrogen atom and then rearranges to form naphthalene through a series of ring closures and openings. The importance of forming the {single_bond}CR({center_dot}){single_bond}CHR{single_bond}CR{prime}{double_bond}CR{double_prime}-moiety, which can undergo rearrangement to form three-carbon-atom ring structures, is illustrated with the C{sub 4}H{sub 7} system. The ability of hydrogen atoms to migrate around the cyclopentadienyl moiety is illustrated both for methyl-cyclopentadiene, C{sub 5}H{sub 5}CH{sub 3}, and dihydrofulvalene, C{sub 5}H{sub 5}C{sub 5}H{sub 5}, as well as for their radical species, C{sub 6}H{sub 7} and C{sub 5}H{sub 5}C{sub 5}H{sub 4}. The mobility of hydrogen in the cyclopentadienyl moiety plays an important role both in providing resonance-stabilized radical products and in creating the {single_bond}CR({center_dot}){single_bond}CHR{single_bond}CR{prime}{double_bond}CR{double_prime}-moiety for ring formation. The results illustrate the radical pathway for converting five-membered rings to aromatic six-membered rings. Furthermore, the results indicate the important catalytic role of H atoms in the aromatic ring formation process.
Date: February 1, 1996
Creator: Melius, C.F.; Colvin, M.E.; Marinov, N.M.; Pitz, W.J. & Senkan, S.M.
Partner: UNT Libraries Government Documents Department