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CreatorTitleDescriptionSubjectDate
251 Voth, Gregory Alan; Ayton, Gary S.Role of protein interactions in defining HIV-1 viral capsid shape and stability: a coarse-grained analysisCoarse-grained models of the HIV-1 CA dimer are constructed based on all-atom molecular dynamics simulations. Coarse-grained representations of the capsid shell, which is composed of approximately 1,500 copies of CA proteins, are constructed and their stability is examined. A key interaction between...Virus capsid; HIV-1; Viral capsid shape; Coarse-graining; CA dimer2010-01
252 Armentrout, Peter B.Cobalt carbene ion: reactions of Co+ with C2H4, cyclo-C3H6 and cyclo-C2H4OAn ion beam apparatus is employed to study the formation of the cobalt carbene ion, CoCH2+. This ion is produced in the endothermic reaction of cobalt ions with ethene and cyclopropane and in an exothermic reaction with ethylene oxide. A model is proposed to account for the dependence of experimenta...Cobalt carbine; Ion beam; Bond dissociation energy; Reaction cross section; Endothermic reactions1981
253 Stang, Peter J.Self-selected formation of single discrete supramolecules with flexible, bidentate ligands in the coordination-driven self-assemblyFlexible donor ligands like 1,2-bis(3-pyridyl)ethyne or 1,4-bis(3-pyridyl)-1,3-butadiyne selfassemble into discrete 2-D supramolecules instead of infinite networks upon combination with organoplatinum 90, 120, and 180 degree acceptor units. These systems are unique examples of versatile pyridine...Bidentate ligands; Flexible donor ligands; Supramolecules; Coordination-driven self-assembly2008
254 Miller, Joel Steven; Epstein, Arthur J.New polymorph of 4,4'-(Butadiyne-1,4-diyl)-bis-(2,2,6,6-tetramethyl-4-hydroxypiperidin-1-oxyl)A new polymorph of the title diradical has been characterized by X-ray diffraction, vibrational spectroscopy, and magnetic susceptibility; its radiation induced polymerization has not been achieved, but thermal treatment turns the crystals black and explosive decomposition occurs at-140 °C.Ferromagnetic; Polymerization; Magnetic1988
255 Miller, Joel Steven; Epstein, Arthur J.; Zhang, JieReentrance in the Mn(tetracyanoethylene)x.y(CH2Cl2) high-Tc molecule-based ferrimagnetResults of static and dynamic magnetic studies of the compound Mn(TCNE)x•y(CH2Cl2) (TCNE =tetracyanoethylene) are reported. Curie-Weiss analysis of the high-temperature susceptibility data indicates a relatively strong exchange. The ac susceptibility, measured as a function of frequency and tempe...Transition; Reentrant; Magnetic1998
256 Miller, Joel Steven ; Epstein, Arthur J.Thermoelectric-power studies of (N-Methylphenazinium)x(Phenazine)1-x(Tetracyanoquinodimethanide), (0.5 <_ x <_ 1.0)Temperature-dependent thermoelectric-power (S) studies of (N-methylphenaziniurn)(x)- (phenazine) (1-x) (tetracyanoquinodimethanide) [(NMP)x(phen) (1-x)(TCNQ) 1 show that for x = 0.5, S(T) is indentical to that of (quinolinium) (TCNQ)2. S(T) for 0.5 <x < 1.0 is intermediate between that of (NMP)(TC...Semiconducting; Doping1979
257 Armentrout, Peter B.Infrared multiple photon dissociation spectroscopy of cationized methionine: effects of alkali-metal cation size on gas-phase conformationPlease note that as of 11-07-2012, access to this article through USpace had to be restricted. The gas-phase structures of alkali-metal cation complexes of the amino acid methionine (Met) as well as protonated methionine are investigated using infrared multiple photon dissociation (IRMPD) spectros...2010
258 Miller, Joel StevenThree-dimensional network-structured cyanide-based magnetsIntroduction Magnets based on metal oxides have been important for hundreds of years. Magnetite, Fe3O4, Co-doped (y)-Fe2O3, and CrO2 are important examples. The oxide (O2-) bridge between the magnetic metal ions has filled p orbitals (Figure 1a) that provide the pathway for strong spin coup...Magnetic; Ferrimagnetic; Magnetization2000
259 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
260 Miller, Joel Steven; Epstein, Arthur J.Noise-power studies of the nearly commensurate quasi-one-dimensional conductor (N-methylphenazinium)x(phenazine)1-x(7,7,8,8-tetracyano-p-quinodimethane) [(NMP)x(Phen)1-x(TCNQ)We report the noise power of (NMP)x(Phen)1-x(TCNQ) as a function of temperature (100 <_ T <_ 300 K), frequency (1<_f<_10(4) Hz), electric field (0 <_E<_300 V/cm), and conduction-electron density (0.49<_x<_0.59). The results for the commensurate, doped commensurate, and incommensurate regimes are sim...Fluctuations; Solitons1985
261 Morse, Michael DavidSpectroscopy and electronic structure of jet-cooled Al?Resonant two-photon ionization spectroscopy has been used to study the jet-cooled Al? molecule. The ground state has been conclusively demonstrated to be of 3IIu symmetry, deriving from the ???rr?u electronic configuration. High resolution studies have established the bond length of the X?IIu state ...1990
262 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
263 Miller, Joel Steven; Epstein, Arthur J.X-ray observation of crossover of 2kF to 4kF scattering in (N-Methylphenazinium)x(Phenazine)1-x(Tetracyanoquinodimethane) [(NMP)x(Phen)1-x(TCNQ)], 0.5 (< _x <_ 1.0)We report the temperature-dependent x-ray diffuse scattering of (NMP),(Phen)(1-x-)(TCNQ) as a function of conduction-electron density (x). With decreasing x three different unique electronic instability regimes are successively observed on the TCNQ chains: (i) the 2kF instability for (2/3<_x<_1, (ii...Conduction-electron; Electron density; Chain1982
264 Baehr, Wolfgang; Prestwich, Glenn D.Photoreceptor cGMP phosphodiesterase delta subunit (PDEdelta) functions as a prenyl-binding proteinBovine PDEdelta was originally copurified with rod cGMP phosphodiesterase (PDE) and shown to interact with prenylated, carboxymethylated C-terminal Cys residues. Other studies showed that PDEdelta can interact with several small GTPases including Rab13, Ras, Rap, and Rho6, all of which are prenylate...Fluorescence Resonance Energy Transfer; GTP Phosphohydrolases; Immunohistochemistry2004
265 Armentrout, Peter B.Threshold collision-induced dissociation of hydrated cadmium (II): experimental and theoretical investigation of the binding energies for Cd2+(H2O)n complexes (n = 4-11)The first experimentally determined hydration energies of Cd2+(H2O)n complexes, n = 4 - 11, are measured using threshold collision-induced dissociation in a guided-ion-beam tandem mass spectrometer coupled with an electrospray-ionization source. Kinetic-energy-dependent cross-sections are obtained a...Hydrated cadmium; Collision-induced dissociation; Hydration energies; Cadmium complexes2010-02
266 Poulter, Charles DalePrenyltransferase. Kinetic studies of the 1'-4 coupling reaction with avian liver enzyme.Prenyltransferase catalyzes the sequential, irreversible 1'-4 condensation of isopentenyl-PP with dimethylallyl-PP and geranyl-PP to yield farnesyl-PP. A kinetic study shows substrate inhibition by isopentenyl-PP at concentrations above 0.7 microM when the concentration of geranyl-PP is 1.0 microM o...Birds; Kinetics; Structure-Activity Relationship; Substrate Specificity1979-10-10
267 Miller, Joel StevenCharge transfer complexes of 2,4,6-tricyano-s-triazine with tetrathiafulvalene (TTF) and N,N,N' ,N'-tetramethyl-p-phenylenediamine (TMPD)Reaction of 2,4,6-tricyano-s-triazine (TCT) with tetrathiafulvalene (TTF) and N,N,N',N'-tetramethylp-phenylenediamine (TMPD) leads to 1 : 1 charge transfer complexes. The crystal structures of the TTF[TCT], as well as the decomposition product due to hydrolysis of the [TMPD][TCT], i.e. HTMPD]+[2,4-d...Electron; Solution; Hydrolysis2002
268 Miller, Joel Steven; Epstein, Arthur J.Spin frustration and metamagnetic behavior in a molecular-based quasi 1-D-ferrimagnetic chain: (MnTPP)(TCNE)We report an experimental observation of spin frustration and metamagnetic behavior in a quasi-1D ferrimagnetic chain, (MnTPP) + (TCNE) -. Metastability, hysteresis effects, and irreversibility of thermal and magnetic histories are observed in magnetization measurements. The "memory" phenomenon is ...Magnetic; Magnetization; Anisotropy1993
269 Stang, Peter J.Self-assembly of coordinative supramolecular polygons with open binding sitesThe design and synthesis of coordinative supramolecular polygons with open binding sites is described. Coordination-driven self-assembly of 2,6-bis(pyridin-4-ylethynyl)pyridine with 60? and 120? organoplatinum acceptors results in quantitative formation of a supramolecular rhomboid and hexagon, resp...2010
270 Miller, Joel StevenStructure, optical and magnetic behaviour of meso-tetraphenyl-porphyrinatoiron(III) tetracyanoethenide, [FeIII(TPP)]+[TCNE].-*The direct redox reaction between tetracyanoethylene (TCNE) and meso-tetraphenylporphyrinatoiron(II), [FeII(TPP)], formed the electron transfer salt (ETS) [FeIII(TPP)][TCNE], which has been structurally, spectroscopically, and magnetically characterized. It has an extended one-dimensional linear ch...Magnets; Spin; Electron2001
271 Morse, Michael DavidNi? revisited: reassignment of the ground electronic stateResonant two-photon ionization spectroscopy was used to study jet-cooled Ni2 produced by pulsed laser ablation of a nickel target in the throat of a supersonic nozzle using argon as the carrier gas. Spectral regions previously investigated using helium as the carrier gas were reinvestigated, and the...1994
272 Armentrout, Peter B.Spin-orbit state-selected reactions of Xe+(2P3/2 and 2P1/2) with H2, D2, and HDSpin-orbit state-selected reactions of X e + (2Pj ), j = 3/2 and 1/2, with isotopic molecular hydrogen (H2 , D2 , and HD) to form X e H + and XeD + are studied using guided ion beam mass spectrometry. Reaction cross sections are determined as a function of reactant kinetic energy from near thermal ...Spin-orbit; Xenon ions; Hydrogen isotopes; Isotope effects; Ion-molecule reactions1989
273 Miller, Joel StevenMagnetization and static scaling of high-Tc disordered molecular-based magnet V(tetracyanoethylene)x¢y(CH3CN) with x ~ 1.5 and y ~ 2)We report field (H) and temperature (T) -dependent magnetization (M) of a member of the new class of high-Tc molecular-based magnets V(tetracyanoethylene)x .y(solvent) with Tc in an accessible range (solvent =CH3CN). The M (H) at low T saturates slowly with increasing H. The random magnetic anisotro...Temperature; Magnetic; Random1993
274 Armentrout, Peter B.C+(2P) + H2(D2,HD)→CH+(CD+) + H(D). I. Reaction cross sections and kinetic isotope effects from threshold to 15 eV c.m.Total cross sections for the reactions of carbon (1 + ) ions with isotopic molecular hydrogen (H2, D2 , and HD) to form methyliumylidene (CH+ and C D + ) have been measured using guided ion beam techniques. Cross sections are reported as a function of the translational energy of the reactants fro...Ion-molecule reactions; Isotope effects; Translational energy; Threshold behavior; Endothermic reactions1986
275 Armentrout, Peter B.Endothermic reactions of uranium ions with N2, D2, and CD4The assessment of new technology for isotope separation has revived an interest in the spectroscopy, properties, and reactions of uranium and its compounds. Newer methods which have been demonstrated include the use of lasers to selectively excite a particular uranium isotope with subsequent chemic...Uranium ions; Nitrogen1977
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