Eric Van Quaquebeke、Gentiane Simon、Aurélie André 等 13 位作者2005-01-19Journal of Medicinal Chemistry
Analysis of the methanolic extract of Calotropis procera root barks enabled the identification of a novel cardenolide (2''-oxovoruscharin) to be made. Of the 27 compounds that we hemisynthesized, one (23) exhibited a very interesting profile with respect to its hemisynthetic chemical yield, its in vitro antitumor acti…
Phytochemical Studies and BioactivitiesBioactive Compounds and Antitumor AgentsPhytochemistry and Bioactive Compounds
Andreas Heyden、Baron Peters、Alexis T. Bell 等 4 位作者2005-01-19The Journal of Physical Chemistry B
The reaction mechanism for nitrous oxide decomposition has been studied on hydrated and dehydrated mononuclear iron sites in Fe-ZSM-5 using density functional theory. In total, 46 different surface species with different spin states (spin multiplicity M(S) = 4 or 6) and 63 elementary reactions were considered. Heats o…
Zeolite Catalysis and SynthesisCatalytic Processes in Materials ScienceCatalysis and Hydrodesulfurization Studies
Lianxi Shen、Jackie Li2005-01-19Physical Review B
Five independent effective elastic moduli of a transversely isotropic multiwalled carbon nanotube (MWNT) are studied by analyzing its deformations under four loading conditions, i.e., axial tension, torsional moment, in-plane biaxial tension, and in-plane tension-compression stress. Two distributions of the tension lo…
Nonlocal and gradient elasticity in micro/nano structuresBoron and Carbon Nanomaterials ResearchCarbon Nanotubes in Composites
Jinlong Wu、R. Andrew Davies、M. Saïful Islam 等 4 位作者2005-01-19Chemistry of Materials
Rare earth (or yttrium) doped BaCeO 3 has been widely investigated as a proton conducting material. Usually, the trivalent dopants are assumed to occupy the Ce 4+ -site, which introduces oxygen vacancies into the perovskite structure and furthers the protonic conductivity. Recent studies indicate the possibility of do…
Advancements in Solid Oxide Fuel CellsThermal Expansion and Ionic ConductivityAdvanced Condensed Matter Physics
Husin Sitepu、B. H. O’Connor、Deyu Li2005-01-19Journal of Applied Crystallography
Preferred crystallographic orientation, i.e. texture in crystalline materials powder diffraction data, can cause serious systematic errors in phase composition analysis and also in crystal structure determination. The March model [Dollase (1986). J. Appl. Cryst. 19 , 267–272] has been used widely in Rietveld refinemen…
X-ray Diffraction in CrystallographyCrystal Structures and PropertiesNuclear materials and radiation effects
Brian C. J. Moore、John A. Leigh2005-01-19Journal of Bacteriology
Among the archaea, Methanococcus maripaludis has the unusual ability to use L- or D-alanine as a nitrogen source. To understand how this occurs, we tested the roles of three adjacent genes encoding homologs of alanine dehydrogenase, alanine racemase, and alanine permease. To produce mutations in these genes, we devise…
Metabolism and Genetic DisordersEnzyme Structure and FunctionAmino Acid Enzymes and Metabolism
R. Nirmala、S. K. Malik、A. V. Morozkin 等 8 位作者2005-01-19arXiv
A new ternary intermetallic compound, namely, YbMn2Sb2, has been synthesized and its magnetic and electrical transport properties have been studied in the temperature range of 2 to 300 K. This compound crystallizes in a trigonal, La2O2S type structure (space group P3bm1, No. 164) and is found to be ferromagnetically o…
Materials Science
Yasemin Kurtulus、Richard Dronskowski、German Samolyuk 等 4 位作者2005-01-19Physical Review B
Density-functional studies of the electronic structures and exchange interaction parameters have been performed for a series of ferromagnetic full Heusler alloys of general formula ${\mathrm{Co}}_{2}\mathrm{Mn}Z$ $(Z=\mathrm{Ga},\mathrm{Si},\mathrm{Ge},\mathrm{Sn})$, ${\mathrm{Rh}}_{2}\mathrm{Mn}Z$ $(Z=\mathrm{Ge},\ma…
Heusler alloys: electronic and magnetic propertiesAdvanced Thermoelectric Materials and DevicesChalcogenide Semiconductor Thin Films
Steven D. Brown、Jonas C. Peters2005-01-19Journal of the American Chemical Society
Pseudotetrahedral iron(II) coordination complexes that contain bridged nitride and terminal imide linkages, and exhibit singlet ground-state electronic configurations, are described. Sodium amalgam reduction of the ferromagnetically coupled dimer, {[PhBP(3)]Fe(mu-1,3-N(3))}(2) (2) ([PhBP(3)] = [PhB(CH(2)PPh(2))(3)](-)…
Metal-Catalyzed Oxygenation MechanismsMagnetism in coordination complexesLanthanide and Transition Metal Complexes
Hongqi Xiang、Kyusoon Shin、Taehyung Kim 等 6 位作者2005-01-19Macromolecules
1055-1056
Surface Chemistry and CatalysisBlock Copolymer Self-AssemblyAnodic Oxide Films and Nanostructures
Yongsheng Leng、Peter T. Cummings2005-01-19Physical Review Letters
We perform molecular dynamics simulations to investigate the shear dynamics of hydration water nanoconfined between two mica surfaces at 1 bar pressure and 298 K. Newtonian plateaus of shear viscosity comparable to the bulk value for different hydration layers D=0.92-2.44 nm are obtained. The origin of this persistent…
Electrostatics and Colloid InteractionsSpectroscopy and Quantum Chemical StudiesMaterial Dynamics and Properties
G. V. Kurlyandskaya、S. M. Bhagat2005-01-19arXiv
During the past ten years nanostructures have been subject of active research. Fabrication of such systems follows well developed methods. The increase in the number of materials available for research and applications requires that the methods of their characterization be even more precise then before. Thin film stru…
Materials Science
S. Pal、M. K. Sanyal、Neena S. John 等 4 位作者2005-01-19arXiv
Gold nanoclusters encapsulated with organic molecules are of great interest for its possible applications in the fields of molecular electronics, catalysis and medical science. Here we demonstrate that monolayer and bilayer films of thiol-capped gold nanoclusters can exhibit diode-like properties provided controlled s…
Materials Science
David R. Heine、Gary S. Grest、Edmund B. Webb III2005-01-19arXiv
Molecular dynamics simulations are used to study the spreading of binary polymer nanodroplets in a cylindrical geometry. The polymers, described by the bead-spring model, spread on a flat surface with a surface-coupled Langevin thermostat to mimic the effects of a corrugated surface. Each droplet consists of chains of…
Soft Condensed MatterMaterials Science
M. Herz、Ch. Schiller、F. J. Giessibl 等 4 位作者2005-01-19arXiv
The local work function of a surface determines the spatial decay of the charge density at the Fermi level normal to the surface. Here, we present a method that enables simultaneous measurements of local work function and tip-sample forces. A combined dynamic scanning tunneling microscope and atomic force microscope i…
Materials Science
Vasili Perebeinos、J. Tersoff、Phaedon Avouris2005-01-19Physical Review Letters
We find that the optical properties of carbon nanotubes reflect remarkably strong effects of exciton-phonon coupling. Tight-binding calculations show that a significant fraction of the spectral weight of the absorption peak is transferred to a distinct exciton+phonon sideband, which is peaked at around 200 meV above t…
Mechanical and Optical ResonatorsGraphene research and applicationsCarbon Nanotubes in Composites
Mathieu Marchivie、Philippe Guionneau、Jean‐François Létard 等 4 位作者2005-01-19Acta Crystallographica Section B Structural Science
The [FeLn(NCS)2] iron(II) spin-crossover complexes cover a wide range of magnetic behaviour. Owing to the large number of known structural and magnetic data, this series is perfectly adapted to the investigation of the structure-magnetic properties relationship. In this paper we propose a new structural parameter, den…
Metal-Catalyzed Oxygenation MechanismsMagnetism in coordination complexesLanthanide and Transition Metal Complexes
Minkee Choi、Freddy Kleitz、Dinan Liu 等 6 位作者2005-01-19OpenAlex
Free-radical polymerization inside mesoporous silica has been investigated in order to open a route to functional polymer-silica composite materials with well-defined mesoporosity. Various vinyl monomers, such as styrene, chloromethyl styrene, 2-hydroxyethyl methacrylate, and methacrylic acid, were polymerized after i…
Catalysis and Oxidation ReactionsMesoporous Materials and CatalysisCatalytic Processes in Materials Science
Xiaowei Wu、Jiyang Fan、Teng Qiu 等 6 位作者2005-01-19OpenAlex
Using electrochemical etching of a polycrystalline 3C-SiC target and subsequent ultrasonic treatment in water solution, we have fabricated suspensions of 3C-SiC nanocrystallites that luminesce. Transmission electron microscope observations show that the 3C-SiC nanocrystallites, which uniformly disperse in water, have…
Silicon Carbide Semiconductor TechnologiesSilicon Nanostructures and PhotoluminescenceSemiconductor materials and devices
Masayoshi Nakano、Ryohei Kishi、Tomoshige Nitta 等 10 位作者2005-01-19OpenAlex
The dependence of the second hyperpolarizability (gamma) on the diradical character (y) for singlet diradical systems is investigated using a model compound, the p-quinodimethane (PQM) molecule with different both-end carbon-carbon (C-C) bond lengths, by several ab initio molecular orbital and density functional theor…
Nonlinear Optical Materials ResearchSynthesis and Properties of Aromatic CompoundsElectron Spin Resonance Studies