Cheng Wang、Xianhui Bu、Nanfeng Zheng 等 4 位作者2002-06-03Angewandte Chemie
Fein abstimmbare Eigenschaften: Eine Familie dreidimensionaler Gerüst-Indiumchalkogenide wird vorgestellt, die nicht auf Clustern basiert. Die Zusammensetzung des Gerüsts ist hoch flexibel und kontrollierbar. Solch eine Vielfalt bei der Zusammensetzung ermöglicht die Abstimmung struktureller, elektronischer und optisc…
2D Materials and ApplicationsCrystal Structures and PropertiesInorganic Chemistry and Materials
Tanja Weil、Erik Reuther、Kläus Müllen2002-06-03Angewandte Chemie
Dendritische Multichromophore auf der Grundlage eines starren Polyphenylen-Gerüstes enthalten bis zu drei verschiedene Rylen-Chromophore: im fokalen Punkt, im Gerüst und an der Peripherie des Dendrimers. Dadurch wird ein Energiegradient zwischen der Peripherie und dem Dendrimerkern erzeugt, und intramolekularer Transf…
Conducting polymers and applicationsLuminescence and Fluorescent MaterialsDendrimers and Hyperbranched Polymers
Vincent Semetey、Didier Rognan、Christine Hemmerlin 等 7 位作者2002-06-03Angewandte Chemie
Eng verwandt mit der (P)2.614-Helix von γ-Peptiden: Das Harnstoff-Heptamer 1 nimmt in Lösung eine stabile, 2.5-helicale Sekundärstruktur ein, die durch eine Ganghöhe von etwa 5.1 Å sowie 12- und 14-gliedrige Wasserstoffbrückenringe charakterisiert ist. N,N′-verknüpfte Oligoharnstoffe gehören somit zu der wachsenden Fa…
Metal-Organic Frameworks: Synthesis and ApplicationsChemical Synthesis and AnalysisSupramolecular Self-Assembly in Materials
Vincent Semetey、Claude Didierjean、Jean‐Paul Briand 等 5 位作者2002-06-03Angewandte Chemie International Edition
Square-shaped hydrogen-bonded polar nanotubes are formed when the C4-symmetrical all-S cyclotetraurea bearing side chains of alanine self-assembles in the solid state (see picture). The four urea fragments in the macrocyle present an all-trans planar conformation with an unidirectional alignment of all the carbonyl gr…
Synthesis and Properties of Aromatic CompoundsSupramolecular Self-Assembly in MaterialsCovalent Organic Framework Applications
Noel A. Clark、Tommaso Bellini、R.‐F. Shao 等 12 位作者2002-06-03Applied Physics Letters
Chiral smectic A liquid crystal materials of the de Vries type (with molecules tilted relative to the layer normal) exhibit analog field-induced (electroclinic) optic axis rotation accompanied by an increase in birefringence. We identify two such de Vries smectic A* materials and use them to develop and test models fo…
Liquid Crystal Research AdvancementsPlant Reproductive BiologyMolecular spectroscopy and chirality
J.J.J.M. Donners、Brigid R. Heywood、E. W. Meijer 等 5 位作者2002-06-03Chemistry - A European Journal
Poly(propylene imine) dendrimers that are modified with long alkyl chains self-assemble to form well-defined aggregates. The geometry and surface chemistry of the dendrimer assemblies can be varied through the addition of surfactants. These dendrimer/surfactant aggregates can be tuned to template the formation of the…
Polymer composites and self-healingCalcium Carbonate Crystallization and InhibitionDendrimers and Hyperbranched Polymers
Shanrong Zhang、Lydie Michaudet、Shawn C. Burgess 等 4 位作者2002-06-03Angewandte Chemie International Edition
Contrast agent for magnetic resonance imaging: The exchangeable amide protons in the Yb3+ complex of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetamide (see crystal structure) act as efficient antennae for transfer of saturated spins to bulk water. Saturation of all eight protons in a 5 mM solution of this complex…
Advanced MRI Techniques and ApplicationsLanthanide and Transition Metal ComplexesElectron Spin Resonance Studies
Andreas Hirsch2002-06-03Angewandte Chemie
Durch chemische Funktionalisierung einwandiger Kohlenstoffnanoröhren werden die Voraussetzungen für mögliche Anwendungen solcher Nanostrukturen geschaffen. Derivatisierte Röhren zeichnen sich im Unterschied zum Rohmaterial u. a. durch eine gute Löslichkeit aus und sind so einer umfangreichen Charakterisierung und Folg…
Mesoporous Materials and CatalysisPorphyrin and Phthalocyanine ChemistryMolecular Junctions and Nanostructures
Kay-Hyeok An、Jeong Goo Heo、Kwan Goo Jeon 等 10 位作者2002-06-03Applied Physics Letters
We have investigated the change of atomic and electronic structures of fluorinated single-walled carbon nanotubes (SWCNTs) using x-ray photoemission spectroscopy (XPS), electrical resistivity measurements, and transmission electron microscopy (TEM). The fluorine content increases with increasing reaction temperature u…
Carbon Nanotubes in CompositesGraphene research and applicationsFiber-reinforced polymer composites
V. Niel、M. Carmen Muñoz、A.B. Gaspar 等 6 位作者2002-06-03Chemistry - A European Journal
Low-spin, high-spin and spin-transition behaviours have been observed for the doubly interpenetrating three-dimensional bimetallic compounds (FeII(pz)[Ag(CN)2]2).pz (pz = pyrazine), (FeII(4,4'-bipy)2[Ag(CN)2]2) (4,4'-bipy = 4,4'-bipyridine), and (FeII(bpe)2[Ag(CN)2]2) (bpe = bispyridylethylene), respectively. The sing…
Magnetism in coordination complexesMolecular Junctions and NanostructuresOrganic and Molecular Conductors Research
Sang Eon Park、Hyunjun Lee、Yong Chan Cho 等 6 位作者2002-06-03Applied Physics Letters
We report on the discovery of a room-temperature ferromagnetism in Cr-doped GaN single crystals with a Tc=280 K. The addition of Cr into GaN single crystals grown by the flux method induces the lattice constant increase due to the larger Cr atomic radius. In x-ray photoelectron spectroscopy measurement, Cr 2p3/2 core-…
ZnO doping and propertiesGaN-based semiconductor devices and materialsGa2O3 and related materials
S. Rajagopalan、Olga Koper、Shawn Decker 等 4 位作者2002-06-03Chemistry - A European Journal
Nanocrystals of magnesium oxide react with organophosphorus compounds at room temperature by dissociative chemisorption, which we term "destructive adsorption". This process involves cleavage of P-O and P-F bonds (but not P-C bonds) and immobilization of the resultant molecular fragments. These ultrafine powders have…
Flame retardant materials and propertiesClay minerals and soil interactions
Tanja Weil、Erik Reuther、Kläus Müllen2002-06-03Angewandte Chemie International Edition
Dendritic multichromophores based on a rigid polyphenylene scaffold contain up to three different types of rylene chromophores incorporated at the focal point, the scaffold, and the periphery of the dendrimer. An energy gradient between the periphery and the core is thus generated and allows an efficient transfer of e…
Luminescence and Fluorescent MaterialsSynthesis and Properties of Aromatic CompoundsDendrimers and Hyperbranched Polymers
P. Chandra、M. Dawber、P. B. Littlewood 等 4 位作者2002-06-03arXiv
For forty years researchers on ferroelectric switching have used the Kay-Dunn theory to model the thickness-dependence of the coercive field; it works surprisingly well, despite the fact that it is based upon homogeneous nucleation and a small-field expansion, neither of which is realized in thin films. Here we demons…
Materials Science
A. Troupis、Anastasia Hiskia、E. Papaconstantinou2002-06-03PubMed
Fine metal nanoparticles of Ag, Au, Pd, and Pt were obtained at room temperature, by simple mixing of the corresponding metal ions with reduced polyoxometalates (POMs) that serve both as photocatalysts and stabilizers, according to the cycle shown.
Polyoxometalates: Synthesis and ApplicationsNanomaterials for catalytic reactionsPigment Synthesis and Properties
Nicolas Keller、Nadezhda I. Maksimova、Vladimir Roddatis 等 8 位作者2002-06-03Angewandte Chemie International Edition
The microstructure is appealing: Onion-like carbon forms are used for the first time in the field of catalysis and thus open new routes for the potential applications of nonplanar carbon materials. An example is given with the oxidative dehydrogenation of ethylbenzene to styrene (see scheme).
Zeolite Catalysis and SynthesisMesoporous Materials and CatalysisCatalysis and Oxidation Reactions
A. Troupis、Anastasia Hiskia、E. Papaconstantinou2002-06-03Angewandte Chemie International Edition
Fine metal nanoparticles of Ag, Au, Pd, and Pt were obtained at room temperature, by simple mixing of the corresponding metal ions with reduced polyoxometalates (POMs) that serve both as photocatalysts and stabilizers, according to the cycle shown.
Polyoxometalates: Synthesis and Applications
Adam C. Durst、R. N. Bhatt、P. A. Wolff2002-06-03arXiv
The magnetic behavior of insulating doped diluted magnetic semiconductors (DMS's) is characterized by the interaction of large collective spins known as bound magnetic polarons. Experimental measurements of the susceptibility of these materials have suggested that the polaron-polaron interaction is ferromagnetic, in c…
ZnO doping and propertiesMagnetic and transport properties of perovskites and related materialsAdvanced Condensed Matter Physics
Robert Aveyard、Bernard P. Binks、John H. Clint 等 13 位作者2002-06-03OpenAlex
Using a laser tweezers method, we have determined the long-range repulsive force as a function of separation between two charged, spherical polystyrene particles (2.7 microm diameter) present at a nonpolar oil-water interface. At large separations (6 to 12 microm between particle centers) the force is found to decay w…
Surfactants and Colloidal SystemsPickering emulsions and particle stabilizationElectrostatics and Colloid Interactions
Lina Zhang、Dong Ruan、Shanjun Gao2002-06-03OpenAlex
Abstract A novel cellulose solvent, 1.5 M NaOH/0.65 M thiourea aqueous solution, was used to dissolve cotton linters having a molecular weight of 10.1 × 10 4 to prepare cellulose solution. Regenerated cellulose (RC) films were obtained from the cellulose solution by coagulating with sulfuric acid (H 2 SO 4 ) aqueous s…
Advanced Cellulose Research Studiesbiodegradable polymer synthesis and propertiesLignin and Wood Chemistry