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Synthesis, scale-up, and characterization of 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105)

Description: We have synthesized 4OOg of the new, insensitive, energetic heterocycle, 2,6-diamino-3,5-dinitropyrazine-l-oxide (LLM-105) with 81% the energy of HMX and excellent thermal stability. The synthesis is a three step reaction sequence from the commercially available starting material, 2,6-dichloropyrazine, with an overall yield of 36%. In this paper we will describe the scale-up of the synthesis of LLM- 105 and report on performance and shock sensitivity experiments performed on this material.
Date: April 27, 1998
Creator: Pagoria, P. F.
Partner: UNT Libraries Government Documents Department
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A diethyl phosphonate containing oxazoline: Synthesis and characterization of monomer and homopolymer

Description: A diethyl phosphonate oxazoline monomer and its polymer have been synthesized. The monomer appears to polymerize via a ring-opening mechanism giving the expected polyethyleneimine backbone with pendant carbonyl groups. Two distinct molecular weights were produced during polymerization suggesting two mechanisms of chain growth. Studies are underway to elucidate the reasons for this. This polymer has potential as a metal-chelating agent.
Date: May 1, 1995
Creator: Hermes, R.E.; Thompson, R.D. & Valdez, L.S.
Partner: UNT Libraries Government Documents Department
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Quantum symmetry and photoreactivity of azabenzenes

Description: The fundamental processes associated with a photochemical reaction are described with reference to experimental properties of azabenzenes. Consideration of both excitation and relaxation processes led to presentation of the symmetry propagator, a unifying principle which maps system fluctuations (perturbations acting on an initial state) with dissipations (transitions to different states), thus directing the energy flow along competing reactive and nonreactive pathways. A coherent picture of re… more
Date: June 1995
Creator: Chesko, J. D. M.
Partner: UNT Libraries Government Documents Department
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vic-Dioximes as Analytical Reagents

Description: A review of research that has contributed to a better understanding of the solubility relations among vicdioximes is presented. Included are sections on synthesis, analysis, structure, and analytical uses of these complexes (J.R.D.)
Date: March 1, 1962
Creator: Banks, Charles V.
Partner: UNT Libraries Government Documents Department
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Electrochemically-modulated liquid chromatography (EMLC): Column design, retention processes, and applications

Description: This work describes the continued development of a new separation technique, electrochemically-modulated liquid chromatography (EMLC), from column design, retention mechanisms to pharmaceutical applications. The introduction section provides a literature review of the technique as well as a brief overview of the research in each of the chapters. This section is followed by four chapters which investigate the issues of EMLC column design, the retention mechanism of monosubstituted aromatic compo… more
Date: October 8, 1997
Creator: Ting, E. Y.
Partner: UNT Libraries Government Documents Department
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CORRELATIONS BETWEEN PHOTOINDUCED EPR AND PHOTOCONDUCTIVITY INTONE-THF SOLUTION CHARGE-TRANSFER COMPLEX

Description: Reversible photoinduced electron paramagnetic resonance (EPR) signals and photoconductivity were observed when a solution of tetracyancethylene (TCNE) in tetrahydrofuran (THF) was irradiated in the charge-transfer band of the complex formed between these two compounds. The eleven-line hyperfine structure of the EPR spectrum which was obtained demonstrated the presence of TCNE negative ion radical. The concentration of this radical was found to be directly proportional to the square root of the … more
Date: December 8, 1964
Creator: Ilten, David F. & Calvin, Melvin
Partner: UNT Libraries Government Documents Department
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Chemical and biological studies on nucleic acids and derivatives. Progress report, May 1, 1975--July 31, 1976

Description: The photochemical products from N-oxidized purines in solution are strongly dependent on the tautomeric and ionic state of the compounds. Studies have been done on the effect of pH on the quantum efficiencies of photoreduction and photorearrangement of a 1-hydroxypurine, a purine 3-oxide and hypoxanthine 3-oxide, a compound that exists as a tautomeric N-oxide-N-hydroxyl equilibrium. The quantum yields for each photoreaction from each tautomer of the nonionized species and from the anions have b… more
Date: October 1, 1976
Creator: Brown, G. B. & Parham, J. C.
Partner: UNT Libraries Government Documents Department
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[Photochemistry of intermolecular C-H bond activation reactions]. Progress report, [September 15, 1994--March 15, 1995]

Description: Since the last progress report (March 15, 1994), attention was paid to the solution photochemistry of (HBPz*{sub 3})Rh(CO){sub 2} (Pz* = 3,5-dimethylpyrazolyl) at different excitation wavelengths and in various hydrocarbon solvents (n-pentane). Absolute quantum efficiencies were obtained for the intermolecular C-H bond activation at different wavelengths and temperatures. Results indicate that there are two excited states with different reactivities and two reaction channels. The intermediate t… more
Date: December 15, 1994
Creator: Lees, Alistair J.
Partner: UNT Libraries Government Documents Department
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Insensitive explosive

Description: This invention relates to the field of chemistry and, more particularly, to explosives. This invention is the result of a contract with the Department of Energy (Contract No. W-7405-ENG-36). It is desirable to use explosives in weapons and other applications which are less sensitive than the common explosives RDX, TNT, and HMX, since there have been catastrophic explosions of munitions which use these compounds. In preliminary characterization and sensitivity testing, it has been found that 3-a… more
Date: December 31, 1991
Creator: Lee, Kien-yin & Storm, C.B.
Partner: UNT Libraries Government Documents Department
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AN ANALYSIS OF H$sup 3$-THYMIDINE DISTRIBUTION THROUGHOUT THE SHOOT APICAL MERISTEM OF ARABIDOPSIS THALIANA (L.) HEYNH

Description: Sequential autoradiographed sections through the shoot apical meristem of Arabidopsis thaliana treated for six hours with a solution of H/sup 3/- thymidine in combination with 0.1% Tween 20 and dilute mineral solution reveal a differential pattern of labeling, indicative of differential rates of DNA synthesis. This pattern corresponds to the histological zonation of the apex and reveals a sub-apical block of cells in which the amount of incorporation is significantly lower than in the adjacent … more
Date: January 1, 1962
Creator: Brown, J. A. M.; Miksche, J. P. & Smith, H. H.
Partner: UNT Libraries Government Documents Department
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[Towards computer-aided catalyst design: Three effective core potential studies of C-H activation]. Final report

Description: Research in the initial grant period focused on computational studies relevant to the selective activation of methane, the prime component of natural gas. Reaction coordinates for methane activation by experimental models were delineated, as well as the bonding and structure of complexes that effect this important reaction. This research, highlighted in the following sections, also provided the impetus for further development, and application of methods for modeling metal-containing catalysts. … more
Date: December 31, 1998
Partner: UNT Libraries Government Documents Department
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ORBITAL SYMMETRY CONTROL IN THE NITRONE-OXAZIRIDINE SYSTEM.NITRONE PHOTOSTATIONARY STATES

Description: Recent the orbital symmetry rules have been shown to apply to hetero-atom systems such as nitrone thermal cycloaddition reactions and the thermal and photochemical aziridine ring cleavage at the C-C bond. The concerted photocyclization is disrotatory and the reverse thermal cleavage is conrotatory in these molecules with four {pi} electrons. In contrast to the azomethine ylide-aziridine system, the stereochemistry of the nitrone photocyclization to oxaziridine can only be observed on carbon and… more
Date: June 1, 1971
Creator: Splitter, Janet S.; Su, Tah-mun; Ono, Howard & Calvin, Melvin.
Partner: UNT Libraries Government Documents Department
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IRRADIATION OF 3- SUBSTITUTED-2-PHENYLOXAZIRIDINES

Description: It was noted previously that 3-(p-dimethylamino)-2-phenyloxaziridine (I) and 3-(p-dimethylamino)-2-(m-nitrophenyl)oxaziridine were photosensitive. Further study on the irradiation (in a variety of solvents under nitrogen) of (I), 2,3-diphenyloxaziridine (II), and 3-(p-nitrophenyl)-2-phenyloxaziridine (III) indicates the major photoreaction to be cleavage to the aldehyde and an intermediate which forms aniline and azobenzene. There is also formed in the photolysis varying amounts of the correspo… more
Date: August 30, 1967
Creator: Splitter, Janet S. & Calvin, Melvin.
Partner: UNT Libraries Government Documents Department
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The Effects of Indoleacetic Acid and Kinetin on the Growth of Some Microorganisms

Description: Data are presented from a study of the effects of indoleacetic acid and kinetin on the growth of Amoeba proteus, Escherichia coli, and two species of yeast. Data are tabulated and reaction mechanisms are discussed. 95 references. (C.H.)
Date: March 31, 1959
Creator: Kennell, D.
Partner: UNT Libraries Government Documents Department
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Singlet oxygen and organic light-emitting diodes

Description: The preparation of light emitting diodes employing a new class of materials, 5,10-dihetera 5,10-dihydro-indeno[3,2b]indenes, as hole transport agents is described. These materials have been found to be more resistant to degradation by singlet oxygen than a poly(p-phenylene vinylene) (PPV) derivative.
Date: July 1, 1995
Creator: Jacobs, S. J.; Sinclair, M. B.; Valencia, V. S.; Kepler, R. G.; Clough, R. L.; Scurlock, R. D. et al.
Partner: UNT Libraries Government Documents Department
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Environmental significance of biocatalytic conversion of low grade oils

Description: Studies dealing with the interactions between extremophilic microorganisms and crude oils have led to the identification of biocatalysts which through multiple biochemical reactions catalyze desulfurization, denitrogenation, and demetalation reactions in oils. Concurrently, the oils are also converted to lighter oils. These complex biochemical reactions have served as models in the development of the crude oil bioconversion technology to be applied prior to the treatment of oils by conventional… more
Date: September 1, 1996
Creator: Lin, M.S.; Premuzic, E.T.; Lian, H.; Zhou, W.M. & Yablon, J.
Partner: UNT Libraries Government Documents Department
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High-Precision Determinations by Means of High-Absorbancy Spectro- Photometric Method. Application to the Determination of Cobalt in Aluminum

Description: High-absorbancy spectrophotometry was applied to the precise determination of about 0.15% cobalt in aluminum by the 1-(2-pyridylazo)-2- naphthol method. The absorbancies of sample aliquots were measured versus a standard containing 50 mu g of cobalt. The relative concentration error for a single measurement, assuming a 1% transmittancy error, is 0.93% and the coefficient of variation of 5 cobalt determinations is 0.5%. (auth)
Date: April 13, 1959
Creator: Menis, O.
Partner: UNT Libraries Government Documents Department
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Final Report on the Large Scale Demonstration for the Electrochemical Processing of Hanford and Savannah River Site High-Level Waste Simulants

Description: This report details the pilot plant studies of the electrochemical destruction of nitrate, nitrite, and organics from simulated alkaline low-level nuclear waste solutions.
Date: September 21, 1995
Creator: Hobbs, D. T.; Chai, D.; Hartsough, D. & Genders, D.
Partner: UNT Libraries Government Documents Department
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Factoring the contribution of through-space and through-bond interactions to rates of photoinduced electron transfer in donor- spacer-acceptor molecules using ultrafast transient absorption spectroscopy

Description: Contributions from through-space and through-bond interactions to the electronic coupling matrix elements for photoinduced charge separation and recombination in linked donor-spacer-acceptor molecules were studied. The molecules consisted of a 4-piperidinyl-naphthalene-1,8-dicarboximide electron donor and a N-(n-octyl)pyromellitimide electron acceptor attached to the 1,5- and 1,8-positions of either anthracene or dibenzobicyclo(2.2.2)octatriene spacers.
Date: June 1996
Creator: Gosztola, D.; Wang, Bing & Wasielewski, M. R.
Partner: UNT Libraries Government Documents Department
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