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126 - 150 of 338
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CreatorTitleDescriptionSubjectDate
126 Miller, Joel StevenInterpenetrating three-dimensional rutile-like frameworks. Crystal structure and magnetic properties of MnII[C(CN)3]2The interpenetrating double-density rutile-like structure and magnetic properties of MnII[C(CN)3]2 are determined.Spin; Bond; Coupling1998
127 Minteer, Shelley D.Investigating the reversible inhibition model of laccase by hydrogen peroxide for bioelectrocatalytic applicationsThe reversible inhibition of laccase by H2O2 as a bioelectrocatalyst was studied in mediated- and direct electron transfer-based configurations to understand the differences in mechanism. The reversible inhibition of laccase follows a noncompetitive inhibition model when 2,2-azino-bis(3-ethylbenzoth...2014-01-01
128 Miller, Joel StevenInvolvement of titanocene and related species in the reduction of dinitrogen and olefinsSummary Four sequential products have been spectrally detected in the reduction by sodium of dicyclopentadienyltitanium(iv) dichloride: [(77-Cp)2TiCl]2, [(77-Cp)2-Ti]1-2, [(77-Cp)(C5H4)TiH]x, and (77-Cp)(C5H4)TiH2Ti- (C5H4)(77-Cp) ("stable titanocene"); the second of these reacts rapidly and rever...Hydrolysis; Sodium; Pressure1972
129 Miller, Joel StevenIsolation and structural determination of octacyanobutanediide, [C4(CN)8]2-; precursors to M(TCNE)x magnets(**)The reaction of MI2.xMe3CN (M = Mn, Fe) and TCNE (tetracyanoethylene) leads to unprecedented [C4(CN)8]2-U4-metal complexes which have been crystallographically characterized and are precursors to M(TCNE)x-yS magnets.Absorptions; Magnets; Bond1998
130 Miller, Joel StevenIsolation and structural determination of {(1,1,2,2-tetracyano-1,2-ethanediyl)bis[imino(cyanomethylene)]}bis-(cyanamide) ion(2--), [C12N12]2--, a new cyanocarbonThe oxidative degradation of [N(PPh3)2]3[Mnilll(CN)6] leads to the isolation of the unprecedented [C12N12]2- dianion, which is characterized by single-crystal X-ray diffraction and spectroscopic techniques.Cyanogen; Bond; Absorptions1995
131 Poulter, Charles DaleIsolation of Schizosaccharomyces pombe isopentenyl diphosphate isomerase cDNA clones by complementation and synthesis of the enzyme in Escherichia coliIsopentenyl diphosphate (IPP) isomerase catalyzes an essential activation step in the isoprene biosynthetic pathway. The Saccharomyces cerevisiae gene for IPP isomerase, IDI1, was recently isolated and characterized (Anderson, M. S., Muehlbacher, M., Street, I. P., Proffitt, J., and Poulter, C. D. (...Carbon-Carbon; Biosynthesis; Genetics1995-05-12
132 Miller, Joel StevenIsolation of two salts from the reduction of TCNE with [(n-C3H7)4N]I. A further example of long 2.87 Ã pi-C-C bonding in pi-[TCNE]22-Reduction of tetracyanoethylene, TCNE, with tetrakis(n-propyl)ammonium iodide, [Pr4N]I, results in a new example of long pi*-CC bonded pi-[TCNE]22- dimers with a 2.870(4) A(°) intradimer CC bond, which is structurally and spectroscopically characterized. This reaction also results in isolation of ...Synthesis; Intradimer; Crystals2002
133 Miller, Joel StevenIsomeric conformations in a pentaco-ordinated ruthenium compound: crystal and molecular structures of the orange and violet isomers of (Ph3P)2[(CF3)2C2S2]Ru(CO)Summary The molecular conformations of two square pyramidal species, one violet the other orange, both composition (Ph3P)2[(CF3)2C2S2]Ru(CO) are described.Pyramidal, Radiation,1973
134 Poulter, Charles DaleIsopentenyl diphosphate:dimethylallyl diphosphate isomerase. An improved purification of the enzyme and isolation of the gene from Saccharomyces cerevisiae.Isopentenyl diphosphate:dimethylallyl diphosphate isomerase (IPP isomerase) is an enzyme in the isoprenoid biosynthetic pathway which catalyzes the interconversion of the primary five-carbon homoallylic and allylic diphosphate building blocks. We report a substantially improved procedure for purific...Amino Acid Sequence; Base Sequence; Chromatography, Gel; Chromatography, Ion Exchange1989-11-15
135 Poulter, Charles DaleIsoprenyl diphosphate synthases: protein sequence comparisons, a phylogenetic tree, and predictions of secondary structureIsoprenyl diphosphate synthases are ubiquitous enzymes that catalyze the basic chain-elongation reaction in the isoprene biosynthetic pathway. Pairwise sequence comparisons were made for 6 farnesyl diphosphate synthases, 6 geranylgeranyl diphosphate synthases, and a hexaprenyl diphosphate synthase...Catalytic site; Evolution; Farnesyl diphosphate; Geranylgeranyl diphosphate; Prenyltransferase; Substrate binding:1994
136 Armentrout, Peter B.Kinetic energy dependence of Al+ + O2→AlO+ + OThe endothermic reaction of Al+ with O2 is studied using a guided ion-beam apparatus. The reaction cross section is measured as a function of kinetic energy from 0 to 20 eV. The threshold energy for the reaction, E0, is determined from an empirical model to be 3.64 ± 0.04 eV.Ion-molecule reactions; Translational energy; Threshold behavior; Endothermic reactions; Aluminum; Oxygen1986
137 Armentrout, Peter B.Kinetic energy dependence of association reactions. A new thermokinetic method for large systemsThe reactions of bare alkali metal ions (M+5Li+, Na+, or K+) with dimethoxyethane (CH3OCH2CH2OCH3 , (DXE) are studied using guided ion beam tandem mass spectrometry. The bimolecular reaction forms an associative M1(DXE) complex that is long-lived and dissociates back to the reactants. The kinetic en...Collision-induced dissociation; Association reactions; Bond energies; Dimethoxyethane; Alkali metal ions2003
138 Armentrout, Peter B.Kinetic energy dependence of dissociative charge-transfer reactions of He+, Ne+, Ar+, Kr+, and Xe+ with silaneGuided ion-beam techniques are used to measure the cross sections as a function of kinetic energy for reaction of SiH4 with He +, Ne +, Ar +, Kr +, and Xe +. State-specific data for the 2P3/2 ground spin-orbit states of Kr+ and Xe+ are also obtained.Silane; Charge-transfer reactions; Ion-molecule reactions; Ion energy; Rare gas ions; Plasma systems1990
139 Wight, Charles AlbertKinetic study of stabilizing effect of oxygen on thermal degradation of poly(methyl methacrylate)The thermal degradation of poly(methyl methacrylate) (PMMA) has been studied in both pure nitrogen and oxygen-containing atmospheres. The presence of oxygen increases the initial decomposition temperature by 70 °C. The stabilizing effect of oxygen may be explained by forming thermally stable radica...Poly(methyl methacrylate); PMMA; Thermal degradation; Isoconversional method1999
140 Armentrout, Peter B.Kinetic-energy dependence of competitive spin-allowed and spin-forbidden reactions: V++CS2The kinetic-energy dependence of the V++CS2 reaction is examined using guided ion-beam mass spectrometry. Several different ion sources are used to systematically vary the V+ electronic state distributions and elucidate the reactivities of both the ground and excited state V+ cation.Carbon disulfide; Vanadium ions; Transition metal ions; Bond energies; Endothermic reactions; Exothermic reactions1999
141 Wight, Charles AlbertKinetics of thermal decomposition of cubic ammonium perchlorateThe methods of thermogravimetric analysis (TGA) and differential scanning calorimettry (DSC) have been used to study the thermal decomposition of ammonium perchlorate (AP). TGA curves obtained under both isothermal and nonisothermal conditions show a characteristic slowdown at the extents of convers...Thermal decomposition; Cubic ammonium perchlorate; Differential scanning calorimetry1999
142 Morse, Michael DavidLaser excitation spectroscopy of the A and B states of jet-cooled copper dimer: evidence for large electronic isotope shiftsFluorescence excitation spectra recorded for the A-X system of jet-cooled Cu2 show conclusive evidence of a ?? = 0 transition, and the A state is thereby definitively assigned as ??u+. A previous assignment of the B state as ??u+ is confirmed, but the vibrational levels of this state are complicated...1989
143 Morse, Michael DavidLaser vaporization generation of Y ??B+, Y ??B+, and YAI+ for electron spin resonance studies in neon matrices at 4 K: comparison with theoretical calculationsThe first spectroscopic investigation of 89Y 10B+, 89Y 11B+, and 89Y 27Al+ is reported, revealing that both of these diatomic cation radicals have X 4?- electronic ground states. The ions were generated by three high energy techniques in combination with neon matrix isolation at 4 K and studied by e...1992
144 Morse, Michael DavidLaser vaporization generation of the SiB and SiAi radicals for matrix isolation electron spin resonance studies: comparison with theoretical calculations and assignment of their electronic ground states as X ??The first experimental spectroscopic study of the SiB and SiAl diatomic radicals is reported. Electron spin resonance results indicate that both molecules have X 4? ground electronic states, in agreement with earlier theoretical calculations. The SIB and SiAl radicals were generated in neon matrices...1993
145 Miller, Joel Steven; Epstein, Arthur J.Lattice- and spin-dimensionality crossovers in a linear-chain-molecule-based ferrimagnet with weak spin anisotropy[MnOEP][HCBD], a member of the metalloporphyrin family of donor-acceptor molecule-based magnets, consists of isolated ferrimagnetic chains of alternating S=2, [MnOEP], and s=1/2, [HCBD] units (OEP=octaethylporphyrinato and HCBD=hexacyanobutadiene). Analysis of the exchange pathways reveals an exchan...Magnetic; Magnetization; Interchain1997
146 Poulter, Charles DaleLethal mutations in the isoprenoid pathway of salmonella entericaEssential isoprenoid compounds are synthesized using the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway in many gram-negative bacteria, some gram-positive bacteria, some apicomplexan parasites, and plant chloroplasts. The alternative mevalonate pathway is found in archaea and eukaryotes, includin...Isoprenoids; Mutation; Bacteria; Antimicrobials2006
147 Morse, Michael DavidLigand-field theory applied to diatomic transition metals. Results for the d?Ad?B?? states of Ni?, the d?Nid??cu?? states of NiCu, and the d?Ni(?F)d??cu???*? excited states of NiCuA ligand-field theory has been developed for transition-metal diatomics having electronic configurations of d?Ad??B??, d?Ad?B?? and d?A(?F)d??B???*?. The theory treats each atom as a point charge and includes spin-orbit interactions. No contributions due to d-orbital chemical bonding are included. ...1992
148 Miller, Joel Steven; Epstein, Arthur J.Linear chain ferromagnetic charge transfer compoundsCharge transfer complexes possessing a ... DADA ... structure with both the donor, D, and acceptor, A, being S = 1/2 radicals may exhibit cooperative magnetic phenomena. The complex [Fe(C5Me5)2]+ [TCNQ]-. exhibits metamagnetic behavior. The similarly structured [TCNE]-. and [C4(CN)6]-. complexes ar...Spin; Exchange; Molecular1986
149 Miller, Joel Steven; Epstein, Arthur J.Local structural order in the disordered vanadium tetracyanoethylene room-temperature molecule-based magnetWe determined the vanadium oxidation state and local coordination environment in disordered samples of magnetic V[TCNE]x(x=2) prepared by chemical vapor deposition (CVD). Systematic studies of the x-ray absorption near-edge structure (XANES) in this material and reference compounds show that V ions ...Magnetic; Solvent; Structure2004
150 Miller, Joel Steven; Epstein, Arthur J.Magnetic behavior of octaethylporphyrinatomanganese(III) tetracyanoethenide, [MnOEP][TCNE], and hexacyanobutadienide, [MnOEP][C4(CN)6]: the importance of a uniform chain for stabilizing strong effective ferromagnetic coupling[MnOEP][A] {A=[TCNE]'- and [C4(CN)6]'-} have been isolated as extended 1D coordination polymers with trans-U2"[A] bridging ligands with strong {A=[C4(CN)6].-} and weak {A=TCNE].-} ferromagnetic coupling as evidenced from the fit of the magnetic susceptibility to the Curie-Weiss law (0=5.1 and 67.1 K...Crystals; Inversion; Coupling1995
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