Zhaozhong Jiang、Himanshu Azim、Richard A. Gross 等 5 位作者2007-06-06Biomacromolecules
Candida antarctica Lipase B (CALB), a metal-free enzyme, was successfully employed as catalyst for ring-opening copolymerization of omega-pentadecalactone (PDL) with p-dioxanone (DO) under mild reaction conditions (<80 degrees C, atmospheric pressure). Poly(PDL-co-DO) with high molecular weight (Mw > 30 000) and a wid…
Carbon dioxide utilization in catalysisbiodegradable polymer synthesis and propertiesPolymer Nanocomposites and Properties
Silvia Berkner、Dennis W. Grogan、Sonja‐Verena Albers 等 4 位作者2007-06-06Nucleic Acids Research
The extreme thermoacidophiles of the genus Sulfolobus are among the best-studied archaea but have lacked small, reliable plasmid vectors, which have proven extremely useful for manipulating and analyzing genes in other microorganisms. Here we report the successful construction of a series of Sulfolobus-Escherichia col…
Genomics and Phylogenetic StudiesBacterial Genetics and BiotechnologyEnzyme Structure and Function
Shuqiang Ding、Yu‐Ping Zeng、Dongliang Jiang2007-06-06Journal of the American Ceramic Society
Porous mullite (3Al 2 O 3 ·2SiO 2 ) ceramics with an open porosity up to 92.9% were fabricated by a gel freeze‐drying process. An alumina (Al 2 O 3 ) gel mixed with ultrafine silica (SiO 2 ) was frozen and sublimation of ice crystals was carried out by drying the frozen body under a low pressure. Porous mullite cerami…
Advanced ceramic materials synthesisRecycling and utilization of industrial and municipal waste in materials productionGlass properties and applications
Xiaojie Lou、Ming Zhang、Simon A. T. Redfern 等 4 位作者2007-06-06Physical Review B
Following our recent experimental work on electrical fatigue [Phys. Rev. Lett. 97, 177601 (2006)], a theory of a charge-injection fatigue model is developed, emphasizing the extremely high depolarization electric field generated near the electrodes by bound charges at the tip of needlelike domains during switching. In…
Ferroelectric and Piezoelectric MaterialsSemiconductor materials and devicesAcoustic Wave Resonator Technologies
Ling Bing Kong、Z. W. Li、Guochen Lin 等 4 位作者2007-06-06Journal of the American Ceramic Society
DC resistivity, dielectric, and magnetic properties of Mg‐ferrite ceramics (Mg 1− x Cu x Fe 1.98 O 4 , with x =0.10–0.30, and Mg 0.90− x Co x Cu 0.10 Fe 1.98 O 4 , with x =0.05–0.20) were investigated. A primary objective is to develop magneto‐dielectric materials with almost equal values of permeability and permittiv…
Full-Duplex Wireless CommunicationsMagnetic Properties and Synthesis of FerritesElectromagnetic wave absorption materials
Haining An、Baijin Zhao、Zhe Ma 等 8 位作者2007-06-06Macromolecules
ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication to the EditorNEXTShear-Induced Conformational Ordering in the Melt of Isotactic PolypropyleneHaining An, Baijin Zhao, Zhe Ma, Chunguang Shao, Xiao Wang, Yapeng Fang, Liangbin Li, and Zhongming LiView Author Information College of Polymer Science and…
Polymer crystallization and propertiesPolymer Nanocomposites and Propertiesbiodegradable polymer synthesis and properties
José M. Serra、Wilhelm Albert Meulenberg2007-06-06Journal of the American Ceramic Society
A novel method for the preparation of a thin oxidic proton‐conducting electrolyte is presented. This kind of supported film was studied in detail as it is applicable for IT–SOFC, H 2 membranes, and advanced catalytic converters. Thin‐film (∼5 μm) proton‐conducting membranes with the nominal composition BaZr 0.85 Y 0.1…
Advancements in Solid Oxide Fuel CellsFuel Cells and Related MaterialsElectronic and Structural Properties of Oxides
Yue Qi、Raja K. Mishra2007-06-06Physical Review B
The stacking fault energy (SFE) in binary and ternary alloys of Al with common alloying elements was studied using density functional theory. Among these alloying elements, Fe further increases the SFE and Ge reduces the SFE of Al. The alloying elements increase the SFE by increasing the directional inhomogeneity in t…
Electron and X-Ray Spectroscopy TechniquesSemiconductor materials and interfacesCorrosion Behavior and Inhibition
M. I. Katsnelson、K. S. Novoselov2007-06-06arXiv
Graphene is the first example of truly two-dimensional crystals - it's just one layer of carbon atoms. It turns out to be a gapless semiconductor with unique electronic properties resulting from the fact that charge carriers in graphene demonstrate charge-conjugation symmetry between electrons and holes and possess an…
Mesoscale and Nanoscale PhysicsMaterials Science
Xiaohua Kong、Suresh S. Narine2007-06-06Biomacromolecules
Polyurethane (PUR) plastic sheets were prepared by reacting polyols synthesized from canola oil with aromatic diphenylmethane diisocyanate. The properties of the material were measured by dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) as well as tensile…
Polymer Nanocomposites and PropertiesEpoxy Resin Curing ProcessesPolymer composites and self-healing
M. Korkusinski、P. Hawrylak、A. Babinski 等 6 位作者2007-06-06arXiv
We present a theory and experiment demonstrating optical readout of charge and spin in a single InAs/GaAs self-assembled quantum dot. By applying a magnetic field we create the filling factor 2 quantum Hall singlet phase of the charged exciton. Increasing or decreasing the magnetic field leads to electronic spin-flip…
Materials ScienceMesoscale and Nanoscale Physics
Ajay K. Pandey、Jean-Michel Nunzi2007-06-06arXiv
We implement and demonstrate a scheme that permits to drive electroluminescence with an extremely low turn-on voltage. The device behaves like compound semiconductors, in which the electroluminescence turn-on voltage is about the same as the open circuit voltage for the photovoltaic effect. However, the electrolumines…
Materials Sciencecond-mat.other
Wojciech Wełnic、Silvana Botti、Lucia Reining 等 4 位作者2007-06-06Physical Review Letters
Several chalcogenide alloys exhibit a pronounced contrast between the optical absorption in the metastable rocksalt and in the amorphous phase. This phenomenon is the basis for their application in optical data storage. Here we present ab initio calculations of the optical properties of GeTe and Ge1Sb2Te4 in the two p…
Phase-change materials and chalcogenidesNonlinear Optical Materials StudiesChalcogenide Semiconductor Thin Films
Giorgos Fagas、James C. Greer2007-06-06arXiv
For investigation of electron transport on the nanoscale, a system possessing a simple to interpret electronic structure is composed of alkane chains bridging two electrodes via end groups; to date the majority of experiments and theoretical investigations on such structures have considered thiols bonding to gold elec…
Materials Sciencecond-mat.other
F. Glas、J. -C. Harmand、G. Patriarche2007-06-06arXiv
We develop a nucleation-based model to explain the formation of the wurtzite (WZ) crystalline phase during the vapor-liquid-solid growth of free-standing nanowires of zinc-blende (ZB) semiconductors. We first show that, in nanowires, nucleation generally occurs at the outer edge of the solid/liquid interface (the trip…
Materials Science
S. Valencia、A. Gaupp、W. Gudat 等 6 位作者2007-06-06arXiv
Surface magnetic properties of perovskite manganites have been a recurrent topic during last years since they play a major role in the implementation of magnetoelectronic devices. Magneto-optical techniques, such as X-ray magnetic circular dichroism, turn out to be a very efficient tool to study surface magnetism due…
Strongly Correlated ElectronsMaterials Science
Philippe Colomban、Raphaël Paquin2007-06-06arXiv
The use of micro-Raman spectroscopy, through chemical bond nano-scale probes, allows the changes in conformations (alpha helix -> beta sheet), chain orientation, disconnection of disulfide bonds (-20%) and the increase of intra and inter-chain distances during the strain to be distinguished. The combination of micro-R…
Materials Science
Irene Puerto-Gimenez、Marek Korkusinski、Pawel Hawrylak2007-06-06arXiv
We present a computational LCHO-CI approach allowing for the simulation of exchange interactions in gated lateral quantum dot networks. The approach is based on single-particle states calculated using a linear combination of harmonic orbitals (LCHO) of each of the dots, and a configuration interaction (CI) approach to…
Materials ScienceMesoscale and Nanoscale Physics
Philippe Colomban、Gwénael Gouadec2007-06-06arXiv
The interest of micro and tip-enhanced Raman spectroscopy to analyze nanosized and nanostructured materials, chiefly semiconductors, oxides and pristine or functionalized carbon nanotubes, is reviewed at the light of the contributions to this special issue. Particular attention is paid to the fact that chemical reacti…
Materials Science
Steven J. Darnell、David Page、Julie C. Mitchell2007-06-06Proteins Structure Function and Bioinformatics
Protein-protein interactions can be altered by mutating one or more "hot spots," the subset of residues that account for most of the interface's binding free energy. The identification of hot spots requires a significant experimental effort, highlighting the practical value of hot spot predictions. We present two know…
Protein Structure and DynamicsEnzyme Structure and FunctionProtein Kinase Regulation and GTPase Signaling