G. Goldoni、F. Rossi、E. Molinari1998-04-03arXiv
We propose a new type of hybrid systems formed by conventional semiconductor nanostructures with the addition of remote insulating layers, where the electron-hole interaction is enhanced by combining quantum and dielectric confinement over different length scales. Due to the polarization charges induced by the dielect…
Materials Science
Dario Alfe`、Stefano de Gironcoli、Stefano Baroni1998-04-03arXiv
We report on a first-principles study of the structure of O/Rh(001) at half a monolayer of oxygen coverage, performed using density-functional theory. We find that oxygen atoms sit at the center of the black squares of a chess-board, $c(2\times 2)$, pattern. This structure is unstable against a rhomboid distortion of…
Materials Science
T. Schneider、E. Gerhardt、Minsu Lee 等 6 位作者1998-04-02Biochemistry
Crystal structures of wild-type tryptophan synthase alpha2beta2 complexes from Salmonella typhimurium were determined to investigate the mechanism of allosteric activation of the alpha-reaction by the aminoacrylate intermediate formed at the beta-active site. Using a flow cell, the aminoacrylate (A-A) intermediate of…
Enzyme Structure and FunctionBiochemical and Molecular ResearchBiochemical Acid Research Studies
M. Bahiana、W. A. M. Morgado1998-04-02arXiv
The microphase separation of a diblock copolymer melt confined by hard walls and in the presence of a gravitational field is simulated by means of a cell dynamical system model. It is found that the presence of hard walls normal to the gravitational field are key ingredients to the formation of well ordered lamellae i…
Materials Science
Pier Luigi Silvestrelli、Nicola Marzari、David Vanderbilt 等 4 位作者1998-04-02arXiv
We use the maximally-localized Wannier function method to study bonding properties in amorphous silicon. This study represents, to our knowledge, the first application of the Wannier-function analysis to a disordered system. Our results show that, in the presence of disorder, this method is extremely helpful in provid…
Materials Science
Isaac Amidror1998-04-01Journal of the Optical Society of America A
The class of second-order curvilinear gratings consists of all the curvilinear gratings that are obtained by second-order spatial transformations of periodic gratings. It includes, for example, circular, elliptic, and hyperbolic gratings as well as circular, elliptic, and hyperbolic zone plates. Such structures occur…
Photonic and Optical DevicesPhotorefractive and Nonlinear OpticsOptical Coatings and Gratings
J. A. Jupp、Heidi Price1998-04-01The Aeronautical Journal
Abstract The anticipated size of the world airliner market over the period 1997-2016, and the resultant requirements for aluminium plate and extrusions to satisfy potential Airbus wing box production is reviewed. The ‘value’ of technology and the threat posed by polymer composites to the future of aluminium alloys for…
Fiber-reinforced polymer compositesMaterial Properties and ApplicationsGraphite, nuclear technology, radiation studies
Akira Endo、Jim Henshaw、M.A. Mignanelli1998-04-01Health Physics
Time-dependent chemical compositions for 13N and 15O induced in the air atmosphere of a high energy electron accelerator room have been studied using a computer simulation method. A radiation chemistry model was developed to describe the chemical reactions of 13N and 15O species with the air molecules and their radiol…
Radiation Therapy and DosimetryRadiation Effects and DosimetryGraphite, nuclear technology, radiation studies
Takashi Yoshizawa、Hiroharu Satoh、Hideki Ohsawa1998-04-01Japanese Journal of Applied Physics
The complementary allocated pit address (CAPA) signal in a digital versatile rewritable disc (DVD-RAM) is susceptible to an objective lens radial shift; the reduction of its signal amplitude occurs and the S/N ratio decreases. To alleviate this situation, we propose a new readout signal processing scheme, the center s…
Phase-change materials and chalcogenidesSemiconductor Lasers and Optical DevicesCellular Automata and Applications
Hsiu-Fung Cheng、Chen-Ti Hu Chen-Ti Hu、Yen-Yi Lin 等 4 位作者1998-04-01Japanese Journal of Applied Physics
A core-shell microstructure is adopted to account for the unique resistivity-temperature (ρ– T ) behavior of (Pb 0.6 Sr 0.4 )TiO 3 materials prepared by the rapid thermal sintering (RTS) process. Instead of a V–shaped temperature coefficient of resistivity (VTCR) with critical temperature ( T ′ c1 ) at around 220°C, c…
Ferroelectric and Piezoelectric MaterialsMagnetic and transport properties of perovskites and related materialsMicrowave Dielectric Ceramics Synthesis
Kinya Kato、Keiji Tanaka1998-04-01Japanese Journal of Applied Physics
Right- and left-handed polymer-dispersed cholesteric (chiral nematic) liquid-crystal (PDCLC) layers are stacked directly between a pair of substrates. Each layer in a device containing these stacked layers exhibits independent characteristics. This is because the PDCLC structure confines the liquid crystal (LC) within…
Liquid Crystal Research AdvancementsPhotonic Crystals and ApplicationsPlant Reproductive Biology
Y.-Q. Zheng、Yu. Grin、Hans Georg̀ von Schnering1998-04-01Zeitschrift für Kristallographie - New Crystal Structures
2nd update of database ICSD in 1998, CSD
Magnetism in coordination complexesLanthanide and Transition Metal ComplexesPolyoxometalates: Synthesis and Applications
Keiji Imado、Yasutoshi Kido、H. Miyagawa 等 4 位作者1998-04-01Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology
Temperature rises of various oils were measured in both impact tests and quasi-adiabatic compression tests. A steel ball impacted against an oiled sapphire glass in the impact test. It was found that the maximum temperature rise was 45 °C in impact tests. A close relationship between temperature rise and α a max was f…
High-Velocity Impact and Material BehaviorSports Dynamics and Biomechanics
С. А. Гусев、Yu. N. Nozdrin、D. B. Rozenshtein 等 4 位作者1998-04-01Technical Physics
The results of studies of the effect of thermal annealing on the magnetic properties of thin films of Co-Pd alloys are described, along with a method for obtaining easy-axis perpendicular anisotropy in these materials. The method consists of depositing layers of the alloy on a substrate whose thermal expansion coeffic…
Magnetic properties of thin filmsMicrostructure and Mechanical Properties of SteelsMagnetic Properties and Applications
Ingrid Milošev、Hans‐Henning Strehblow、B. Navinšek 等 4 位作者1998-04-01Surface Science Spectra
Zirconium nitride (ZrN) coatings have been deposited on polished steel substrates by a plasma-beam sputtering technique in a Sputron apparatus (Balzers A. G.) at 200 °C. A thin intermediate layer of Zr (0.08 μm) was deposited between the substrate and the 2.8 μm thick ZrN coating. The average roughness, Ra, of the sub…
Semiconductor materials and devicesElectron and X-Ray Spectroscopy TechniquesIon-surface interactions and analysis
Huai‐Ming Hu、Hongsui Sun、Qun Zhao 等 6 位作者1998-04-01Journal of Coordination Chemistry
An imidazolate bridged dinuclear nickel(II) complex, μ-(Im)-[(232-tet)Ni]2(ClO4)3, where 232-tet = N, N′-bis(2-aminoethyl)-l, 3-propanediamine, Im = imidazolate anion, has been synthesized and its crystal structure determined. Crystals are monoclinic, space group C2, with a = 11.982(4), b = 12.320(2), c = 11.711(4) Å,…
Metal-Organic Frameworks: Synthesis and ApplicationsMetal complexes synthesis and propertiesMagnetism in coordination complexes
Ingrid Milošev、Hans‐Henning Strehblow、B. Navinšek 等 4 位作者1998-04-01Surface Science Spectra
Titanium nitride (TiN) coatings have been deposited on polished steel substrates by a plasma-beam sputtering technique in a Sputron apparatus (Balzers A. G.) at 200 °C. A thin intermediate layer of Ti (0.08 μm) was deposited between the substrate and the 2.8 μm thick TiN coating. The average roughness, Ra, of the subs…
Metal and Thin Film MechanicsElectron and X-Ray Spectroscopy TechniquesIon-surface interactions and analysis
Sh. Kheirandish、Sh. Mirdamadi、Y. H. K. Kharrazi1998-04-01Materials Science and Technology
High speed steel is a very difficult materialfor shape casting owing to the formation of eutectic carbide networks during its solidification. These networks cause the steel to be brittle which is detrimental to the mechanical properties of tools manufactured from the material. In the present research, the effect of re…
Microstructure and Mechanical Properties of SteelsAdvanced materials and compositesMetal Alloys Wear and Properties
F. Suhara、Sunil K. Narayanankutty、Golok B. Nando1998-04-01Journal of Elastomers & Plastics
The stress relaxation behavior of polyurethane elastomer and short polyester fiber filled elastomer composites with and without bonding agents at different strain levels and strain rates was studied. It was found that these compounds exhibit a multistage relaxation mechanism and that the rate of relaxation and cross-o…
Polymer crystallization and propertiesPolymer Nanocomposites and PropertiesNatural Fiber Reinforced Composites
E.A.M. Youssef、Nivin M. Ahmed、M.A. Abd El‐Ghaffar1998-04-01Pigment & Resin Technology
Silica waste fume is a byproduct produced in the manufacture of ferrosilicon. The sample, which was very fine and rich in silica, was characterized using chemical and spectrophotometric measurements (XRD and electron microscope). The silica fume was incorporated in anticorrosive paint formulations based on alkyd resin…
Corrosion Behavior and InhibitionSilicone and Siloxane Chemistry