Bertrand Zimmer、V. Bulach、Cathy Drexler 等 6 位作者2002-01-03New Journal of Chemistry
New polynucleating ligands based on a combination of a meso-tetrakis(phenyl)porphyrin core and four catecholamido units connected at the ortho positions of the phenyl moieties have been prepared. All four atropoisomers of the methoxy-protected meso-tetrakis(o-catecholamidophenyl)porphyrin 2 were obtained in high yield…
DNA and Nucleic Acid ChemistryDrug Transport and Resistance MechanismsPorphyrin and Phthalocyanine Chemistry
Philippe Goldner、B. Schaudel、M. Prassas2002-01-03Physical review. B, Condensed matter
Cooperative emission has been recorded in several ${\mathrm{Yb}}^{3+}$ stoichiometric crystals. Its intensity, normalized by the square of the ${}^{2}{F}_{5/2}$ excited level population, is shown to depend only on the ${\mathrm{Yb}}^{3+}$ ions spatial distribution. In most cases, other material dependent parameters do…
Luminescence Properties of Advanced MaterialsGlass properties and applicationsQuantum optics and atomic interactions
Bernadette Bensaude-Vincent、H. Arribart、Yves Bouligand 等 4 位作者2002-01-03New Journal of Chemistry
The term biomimicry first appeared in 1962 as a generic term including both cybernetics and bionics. It referred to all sorts of imitation of one form of life by another one, while the term “bionics”, defined as “an attempt to understand sufficiently well the tricks that nature actually uses to solve her problems”, is…
Diatoms and Algae ResearchCephalopods and Marine BiologyNanotechnology research and applications
Steven P. Newman、William Jones、Paul O’Connor 等 4 位作者2002-01-03Journal of Materials Chemistry
The direct synthesis is reported of a 3R2 polytype of a hydrotalcite-like mineral by the hydrothermal treatment of aluminium oxide and magnesium oxide.
Layered Double Hydroxides Synthesis and ApplicationsInorganic Chemistry and MaterialsMagnesium Oxide Properties and Applications
Stephan Link、Akihiro Furube、Mona B. Mohamed 等 6 位作者2002-01-03The Journal of Physical Chemistry B
To test the influence of the surrounding medium on the relaxation dynamics of the plasmon band bleach recovery of gold nanoparticles after excitation with femtosecond laser pulses, we embedded 14.5 and 12.1 nm colloidal gold nanoparticles (synthesized electrochemically) in MgSO 4 powder and investigated these samples…
Gold and Silver Nanoparticles Synthesis and ApplicationsNonlinear Optical Materials StudiesLaser-Ablation Synthesis of Nanoparticles
Enkhtsetseg Dashjav、Aleksandra Szczepenowska、Holger Kleinke2002-01-03Journal of Materials Chemistry
The binary antimonide Mo3Sb7 is metallic with poor thermoelectric properties. Since band structure calculations indicated a possible change to semiconducting behavior by adding two more valence-electrons, the substitutional series Mo3Sb7 − δTeδ has been investigated. Te atoms can replace up to 2.3 Sb atoms in Mo3Sb7 w…
Advanced Thermoelectric Materials and DevicesIntermetallics and Advanced Alloy PropertiesHeusler alloys: electronic and magnetic properties
Pedro Pablo、Cristina Gómez‐Navarro、J. Colchero 等 6 位作者2002-01-03Physical Review Letters
In this work fundamental properties of the electrical transport of single-walled carbon nanotubes as a function of their length are investigated. For this purpose, we have developed a new technique that allows us to characterize electronic transport properties of single-walled carbon nanotubes by probing them at diffe…
Carbon Nanotubes in CompositesForce Microscopy Techniques and ApplicationsMechanical and Optical Resonators
Nathalie Vast、Lucia Reining、Valério Olevano 等 5 位作者2002-01-03Physical Review Letters
We present an ab initio calculation of the electron energy loss spectrum of rutile TiO2 in the energy range of 0 to 60 eV, focusing our interest on the excitation from the titanium 3p semicore levels. The results are compared to our measurements. Local field effects turn out to be crucial at those energies, and their…
Chalcogenide Semiconductor Thin FilmsTransition Metal Oxide NanomaterialsElectron and X-Ray Spectroscopy Techniques
Stephen D. Kinrade、Ashley-M. E. Gillson、Christopher T. G. Knight2002-01-03Journal of the Chemical Society Dalton Transactions
Cultures of the freshwater diatom Navicula pelliculosa were synchronized by silicon starvation, fed a 29Si-enriched silicate solution, and then studied by 29Si NMR spectroscopy. Two NMR resonances could be detected reproducibly, the ever-present orthosilicic acid peak at −71 ppm and a weak signal at −131.5 ppm that wa…
Geology and Paleoclimatology ResearchGeochemistry and Elemental AnalysisDiatoms and Algae Research
Gang Lü、Daniel Orlikowski、Ickjin Park 等 5 位作者2002-01-03Physical review. B, Condensed matter
The effects of hydrogen impurities in the bulk and on the surface of aluminum are theoretically investigated. Within the framework of density-functional theory, we have obtained the dependence on H concentration of the stacking fault energy, the cleavage energy, the Al/H surface energy, and the Al/H/Al interface forma…
Fusion materials and technologiesHydrogen embrittlement and corrosion behaviors in metalsNuclear Materials and Properties
M. Rusanen、I. T. Koponen、T. Ala-Nissila 等 5 位作者2002-01-03arXiv
The morphological development of step edge patterns in the presence of meandering instability during step flow growth is studied by simulations and numerical integration of a continuum model. It is demonstrated that the kink Ehrlich-Schwoebel barrier responsible for the instability leads to an invariant shape of the s…
Materials Science
Ezekiel Johnston‐Halperin、D. D. Lofgreen、Roland Kawakami 等 7 位作者2002-01-03Physical review. B, Condensed matter
We investigate spin-polarized inter-band tunneling through measurement of a (Ga,Mn)As based Zener tunnel diode. By placing the diode under reverse bias, electron spin polarization is transferred from the valence band of p-type (Ga,Mn)As to the conduction band of an adjacent n-GaAs layer. The resulting current is monit…
Semiconductor Quantum Structures and DevicesZnO doping and propertiesQuantum and electron transport phenomena
Yugang Sun、Byron D. Gates、Brian T. Mayers 等 4 位作者2002-01-03OpenAlex
This paper describes a soft, solution-phase approach to the large-scale synthesis of uniform nanowires of bicrystalline silver whose lateral dimensions could be controlled in the range of 30−40 nm, and lengths up to ∼50 μm. The first step of this procedure involved the formation of platinum nanoparticles by reducing P…
Electrocatalysts for Energy ConversionGold and Silver Nanoparticles Synthesis and ApplicationsAnodic Oxide Films and Nanostructures
Kris Driesen、Philip Lenaerts、Koen Binnemans 等 4 位作者2002-01-02Physical Chemistry Chemical Physics
Optical absorption spectra of monolithic silica sol–gel glasses incorporating the lanthanide complexes [Ln(bpy)2]Cl3, [Ln(phen)2]Cl3 and Ln(NO3)3 (bpy = bipyridyl, 2,2'-bipyridine, phen = 1,10-phenanthroline, Ln = Nd, Sm, Dy, Ho, Er) were recorded. The Judd–Ofelt theory was used to study changes in the coordination sp…
Luminescence Properties of Advanced MaterialsGlass properties and applicationsLanthanide and Transition Metal Complexes
Edwin Kroke2002-01-02Angewandte Chemie International Edition
The application of high-pressure methods in the search for novel materials usually requires additional effort compared to syntheses at ambient pressure. Depending on the desired p/T conditions different methods may be used. Special techniques and experimental apparatus such as shock waves, diamond anvil cells, and mul…
Boron and Carbon Nanomaterials ResearchMXene and MAX Phase MaterialsInorganic Chemistry and Materials
Ho‐Chol Chang、Susumu Kitagawa2002-01-02Angewandte Chemie International Edition
Coexistence of two kinds of ligand-based mixed-valence (LBMV) isomers is observed for the first time in the title compound (see scheme). Together with its mixed-charged state, the compound shows semiconducting behavior with an intermolecular ferromagnetic interaction, which is attributable to the association of five p…
Metal-Organic Frameworks: Synthesis and ApplicationsMagnetism in coordination complexesCrystallography and molecular interactions
Chulsu Jo、Changwook Kim、Young Hee Lee2002-01-02Physical review. B, Condensed matter
We have investigated electronic properties of K-doped single-wall carbon nanotube bundles by the first principles calculations. The lattice expands up to 8% at ${\mathrm{K}}_{0.1}\mathrm{C}$ with negative binding energies, where distortion of tube walls is negligible up to ${\mathrm{K}}_{0.25}\mathrm{C}$ with full rel…
Carbon Nanotubes in CompositesGraphene research and applicationsBoron and Carbon Nanomaterials Research
Emilia La Nave、H. Eugene Stanley、Francesco Sciortino2002-01-02Physical Review Letters
We present a numerical analysis for SiO (2) of the fraction of diffusive direction f(diff) for temperatures T on both sides of the fragile-to-strong crossover. The T dependence of f(diff) clearly reveals this change in dynamical behavior. We find that for T above the crossover (fragile region) the system is always clo…
High-pressure geophysics and materialsMaterial Dynamics and PropertiesTheoretical and Computational Physics
Evan T. Powers、Sung Ik Yang、Charles M. Lieber 等 4 位作者2002-01-02Angewandte Chemie International Edition
Peptide length affects the size of the ridges observed in the atomic force microscopy (AFM) images of the Langmuir–Blodgett films of amphiphilic peptides: Well-ordered LB films can be prepared from a 14-residue amphiphilic peptide (left), while ordered LB films with a wider lattice (right) are obtained from an 18-resi…
Lipid Membrane Structure and BehaviorAntimicrobial Peptides and ActivitiesSupramolecular Self-Assembly in Materials
A. V. Savin、J. M. Khalack、P. L. Christiansen 等 4 位作者2002-01-02Physical review. B, Condensed matter
Topological defects and dislocations in strongly anisotropic crystals consisting of parallel molecular chains are investigated. Our study is focused on the defects in crystalline polyethelyne, which are formed by transverse displacements of chain molecules (mutual substitutions and interlacings of adjacent molecular c…
Carbon Nanotubes in CompositesForce Microscopy Techniques and ApplicationsMechanical and Optical Resonators