Peihong Zhang、Vincent H. Crespi2002-07-15Physical Review Letters
We describe two new boron-based nanotubes: $\text{B}\text{ }{\text{ ︀}}_{2}\text{O}$ and $\text{BeB}\text{ }{\text{ ︀}}_{2}$. Both are isoelectronic to graphite, have reasonable curvature energies, and have already been made in their bulk planar forms. The lowest energy allotrope of planar single-layer $\text{B}\text{…
Graphene research and applicationsBoron and Carbon Nanomaterials ResearchMXene and MAX Phase Materials
Andrey A. Voevodin、John G. Jones、J.S. Zabinski 等 4 位作者2002-07-15Journal of Applied Physics
Chemistry, energy, and spatial distributions of species in carbon–nitrogen plasma plumes were investigated to define plasma conditions for growth of carbon nitride CNx films with a fullerene-like structure. Plumes were generated by ablation of graphite using a 248 nm excimer laser in the presence of low-pressure nitro…
Metal and Thin Film MechanicsDiamond and Carbon-based Materials ResearchLaser-induced spectroscopy and plasma
Gordon Kelly、Frank D. King、M. Kett2002-07-15Green Chemistry
Industrial condensation reactions are usually homogeneously catalysed by strong caustic. Recent work has demonstrated the practical application of heterogenised base catalysts, which enhance selectivity and eliminate the generation of organically contaminated waste caustic streams. A number of successful systems have…
Layered Double Hydroxides Synthesis and ApplicationsPhosphorus and nutrient managementChemical Synthesis and Characterization
Hongwen Ren、Shin‐Tson Wu2002-07-15Journal of Applied Physics
Light-switching behavior of reflective reserved-mode polymer-stabilized-cholesteric-texture (PSCT) was analyzed and validated experimentally. Our results indicate that the reflective reversed-mode PSCT offers a much higher contrast ratio and lower operating voltage than its transmissive counterpart. Effects of cell ga…
Photonic and Optical DevicesLiquid Crystal Research AdvancementsOptical Polarization and Ellipsometry
Juan A. Anta、Gianluca Marcelli、M. Meunier 等 4 位作者2002-07-15Journal of Applied Physics
We present a unified method to estimate current–voltage characteristics of insulators starting from ab initio electronic calculations of the properties of the dielectric material. The method consists of three stages: (1) computation of trap energy distributions for excess electrons by means of density functional theor…
Semiconductor materials and devicesHigh voltage insulation and dielectric phenomenaPower Transformer Diagnostics and Insulation
Christian G. Claessens、Tomás Torres⊗2002-07-15Angewandte Chemie International Edition
The syn and anti topoisomers of fused subphthalocyanine dimers were synthesized and characterized. The space-filling model of the anti topoisomer is depicted. These compounds are the first step towards the synthesis of larger curved π surfaces.
Magnetism in coordination complexesPorphyrin and Phthalocyanine ChemistryOrganic Chemistry Cycloaddition Reactions
Akira Maehara、Seiichi Taguchi、Tatsuaki Nishiyama 等 5 位作者2002-07-15Journal of Bacteriology
Phasins (PhaP) are predominantly polyhydroxyalkanoate (PHA) granule-associated proteins that positively affect PHA synthesis. Recently, we reported that the phaR gene, which is located downstream of phaP in Paracoccus denitrificans, codes for a negative regulator involved in PhaP expression. In this study, DNase I foo…
biodegradable polymer synthesis and propertiesElectrospun Nanofibers in Biomedical ApplicationsMicroplastics and Plastic Pollution
Touru Yamauchi、Yutaka Ueda、N. Môri2002-07-15Physical Review Letters
We report the discovery of a new superconducting phase in highly correlated $3d$ electron systems. The compound is $\ensuremath{\beta}$-vanadium bronze, $\ensuremath{\beta}\ensuremath{-}{\text{Na}}_{0.33}{\text{V}}_{2}{\text{O}}_{5}$, in which the charge-ordered phase collapses under hydrostatic high pressure and a pr…
Transition Metal Oxide NanomaterialsCatalysis and Oxidation ReactionsThermal Expansion and Ionic Conductivity
Swetlana Schauermann、Jens Hoffmann、Viktor Johánek 等 6 位作者2002-07-15Angewandte Chemie International Edition
Catalytically active nanoparticle sites: Different catalytic activity of different active sites coexisting on a supported nanoparticle has been directly observed using molecular-beam techniques and in situ surface vibrational spectroscopy. For methanol decomposition on a supported Pd model catalyst (see picture), it i…
Advanced Chemical Physics StudiesCatalytic Processes in Materials ScienceCatalysis and Oxidation Reactions
L. A. Errico、G. Fabricius、M. Rentería 等 5 位作者2002-07-15Physical Review Letters
We present an ab initio study of the relaxations introduced in TiO (2) when a Cd impurity substitutes a Ti atom and an experimental test of this calculation by a perturbed-angular-correlation (PAC) measurement of the orientation of the electric-field gradient (EFG) tensor at the Cd site. The ab initio calculation pred…
Advancements in Battery MaterialsMagnetic and transport properties of perovskites and related materialsX-ray Diffraction in Crystallography
J.M. Gallardo Fuentes、Paul Gümpel、Joachim Strittmatter2002-07-15Advanced Engineering Materials
Among other special characteristics Shape Memory Alloys (SMAs) have the ability to return to a predetermined shape when heated. In fact, the phase change of an existing element can strongly be influenced by thermal and thermo-mechanical treatments. Up to now, SMEs have been discovered in various materials, which can g…
Advanced Memory and Neural ComputingShape Memory Alloy Transformations
Julia J. Hwang、Subramani N. Iyer、Li-Sheng Li 等 6 位作者2002-07-15Proceedings of the National Academy of Sciences
We report here on the synthesis and characterization of a series of self-assembling biomaterials with molecular features designed to interact with cells and scaffolds for tissue regeneration. The molecules of these materials contain cholesteryl moieties, which have universal affinity for cell membranes, and short chai…
Proteoglycans and glycosaminoglycans researchSeaweed-derived Bioactive CompoundsSupramolecular Self-Assembly in Materials
P. Patsalas、S. Logothetidis、C. Metaxa2002-07-15Applied Physics Letters
Ceria is a transparent oxide suitable for various optical and optoelectronic devices. In this work, we tailor independently the refractive index n and fundamental gap Eg of nanocrystalline Ceria films by varying the substrate temperature or using Ar+ ion beams during growth with electron beam evaporation. Spectroscopi…
Catalytic Processes in Materials ScienceQuantum Dots Synthesis And PropertiesCopper-based nanomaterials and applications
David Djajaputra、Bernard R. Cooper2002-07-15arXiv
We have performed a systematic first-principles computational study of the effects of impurity atoms (boron, carbon, nitrogen, oxygen, silicon, phosporus, and sulfur) on the orbital hybridization and bonding properties in the intermetallic alloy NiAl using a full-potential linear muffin-tin orbital method. The matrix…
Materials Science
X. Chen、M. Na、M. Cheon 等 12 位作者2002-07-15Applied Physics Letters
Digital alloys of GaSb/Mn have been fabricated by molecular-beam epitaxy. Transmission electron micrographs showed good crystal quality with individual Mn-containing layers well resolved, no evidence of three-dimensional MnSb precipitates was seen in as-grown samples. All samples studied exhibited ferromagnetism with…
Magnetic properties of thin filmsZnO doping and propertiesHeusler alloys: electronic and magnetic properties
Thierry Martin、Anne Galarneau、Francesco Di Renzo 等 5 位作者2002-07-15Angewandte Chemie International Edition
Pores for order: Particles of silica gel can be transformed into MCM-41 without losing their size and shape by a low-temperature hydrothermal treatment (see electron micrographs). This method allows easy preparation of custom-tailored materials for chromatography and separation.
Zeolite Catalysis and SynthesisMesoporous Materials and CatalysisPolyoxometalates: Synthesis and Applications
I. Kuryliszyn、T. Wojtowicz、X. Liu 等 10 位作者2002-07-15arXiv
High- and low-field magneto-transport measurements, as well as SQUID measurements of magnetization, were carried out on Ga1-xMnxAs epilayers grown by low temperature molecular beam epitaxy, and subsequently annealed under various conditions. We observe a large enhancement of ferromagnetism when the samples are anneale…
Materials Science
Tatiana Makarova2002-07-15arXiv
We present a collection of experimental evidence on UFOs: Unidentified Ferromagnetic Organic structures. Five types of carbon magnets have been obtained experimentally: 1. Chains of interacting radicals 2. Carbonaceous substances with a mixture of sp2 and sp3 coordinated atoms 3. Amorphous carbon structures containing…
Materials Science
K. Racka、I. Kuryliszyn、M. Arciszewska 等 12 位作者2002-07-15arXiv
The Anomalous Hall Effect was investigated in IV-VI ferromagnetic semimagnetic semiconductors of Sn1-xMnxTe codoped with either Eu or Er. The analysis of experimental data: Hall resisitivity and magnetization showed that AHE coefficient RS depends on temperature, its value decreases with the temperature increase. We o…
Materials Science
S. Kolesnik、B. Dabrowski、J. Mais2002-07-15arXiv
ac susceptibility has been studied for polycrystalline Zn$_{1-x}$Mn$_x$O. Stoichiometric samples demonstrate Curie-Weiss behavior, which indicates mostly antiferromagnetic interactions. Magnetic susceptibility can be described by a diluted Heisenberg magnet model developed for semimagnetic semiconductors. High-pressur…
Materials Science