Materials Literature

文献浏览

按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。

清除
第 146194 / 152062 页 · 当前展示 2,923,861–2,923,880 / 3,041,238 条匹配结果 · 摘要仅作预览

Extrapolated surface dose measurements with radiochromic film

Martin J Butson、K.N. Yu、Peter Metcalfe1999-03-01Medical Physics

A radiochromic film extrapolation method is described for the measurement of surface dose from high energy photon beams. Extrapolated central axis entrance surface dose using Gafchromic film for a field size is and of for 6 and 10 MV x rays, respectively. Extrapolated surface dose for a field with a 10 mm perspex bloc…

Advanced Radiotherapy TechniquesRadiation Therapy and DosimetryRadiation Shielding Materials Analysis

Surface Characterization of Polymers for Medical Devices

Carsten Werner、H.‐J. Jacobasch1999-03-01The International Journal of Artificial Organs

A survey is given on analytical techniques currently applied to the surface characterization of biomedical polymers. The techniques include spectroscopies, thermodynamic and electrochemical measurements and microscopies, respectively. To illustrate the motivation for surface analysis, the hypotheses on the correlation…

Polymer Surface Interaction StudiesForce Microscopy Techniques and ApplicationsAnalytical Chemistry and Sensors

Fabrication of Array of Hollow Microcapillaries Used for Injection of Genetic Materials into Animal/Plant Cells

Kyoseok Chun andHiroyuki Fujita1999-03-01Japanese Journal of Applied Physics

We have proposed a micromachined system with the aim of controlling injection of DNA into cells. The injection system is composed of two components: hollow microcapillaries for injection and microchambers for trapping cells. The hollow microcapillary array, the most important part of the system has been fabricated. In…

Surface Modification and SuperhydrophobicityMicrofluidic and Capillary Electrophoresis ApplicationsElectrospun Nanofibers in Biomedical Applications

Infrared and microwave dielectric response of the disordered antiferroelectric Ag(Ta,Nb)O3system

J. Petzelt、S. Kamba、E. Buixaderas 等 12 位作者1999-03-01Ferroelectrics

Recent progress related to the investigation of infrared and microwave properties of the AgNbO3 and AgTaO3 single crystals and Ag(Ta,Nb)O3 ceramics is reviewed and discussed with the aid of new crystallographic considerations and symmetry approach. It is shown that optical phonons at any temperature contribute to the…

Ferroelectric and Piezoelectric MaterialsAcoustic Wave Resonator TechnologiesMicrowave Dielectric Ceramics Synthesis

Growth and Characterization of Phosphorus Doped n-Type Diamond Thin Films

Satoshi Koizumi1999-03-01physica status solidi (a)

Phosphorus (P) doped diamond thin films were grown by microwave plasma-assisted chemical vapor deposition (CVD) using phosphine (PH3) as a dopant source. The addition of PH3 in the gas ambient significantly influenced the optimal growth condition for diamond. The {111} surface of diamond was found to be the best surfa…

Metal and Thin Film MechanicsHigh-pressure geophysics and materialsDiamond and Carbon-based Materials Research

Computer simulation of damage in diamond due to ion impact and its annealing

D. Saada、Joan Adler、R. Kalish1999-03-01Physical review. B, Condensed matter

The structural modifications that a highly damaged region in diamond undergoes upon thermal annealing have been studied by molecular dynamic simulations. We verified our use of the Tersoff potential and our computational methods for describing the thermally driven transition of diamond to graphite by calculating the t…

High-pressure geophysics and materialsDiamond and Carbon-based Materials ResearchIon-surface interactions and analysis

Theory of Morphotropic Phase Boundary in Solid-Solution Systems of Perovskite-Type Oxide Ferroelectrics: Elastic Properties

Yoshihiro Ishibashi、Makoto Iwata1999-03-01Japanese Journal of Applied Physics

Elastic stiffness constants in a perovskite-type oxide solid-solution system are discussed on the basis of the Landau-type free energy function expressed in terms of polarization and strain components. It is found that some of the elastic stiffness constants become extremely small in the vicinity of the morphotropic p…

Ferroelectric and Piezoelectric MaterialsAcoustic Wave Resonator TechnologiesThermoelastic and Magnetoelastic Phenomena

Reactive Polymer Interfaces: How Reaction Kinetics Depend on Reactivity and Density of Chemical Groups

Ben O’Shaughnessy、Dimitrios Vavylonis1999-03-01Macromolecules

We present a systematic theory of polymer reaction kinetics at an interface separating two immiscible melts, A and B, in each of which a fraction of chains carry reactive end groups. We consider arbitrary values of local group reactivity, Q b, and reactive group densities in either bulk, and, with the convention . At…

Polymer crystallization and propertiesMaterial Dynamics and PropertiesForce Microscopy Techniques and Applications

Low Surface Energy Coatings from Waterborne Nano-Dispersions of Polymer Complexes

Andreas F. Thünemann、Antje Lieske、Bernd‐Reiner Paulke1999-03-01Advanced Materials

Strategies for obtaining low surface energy coating materials; include those for realizing surfaces rich in CF3 groups. Of these, ones that are low in cost and environmentally friendly (for example, avoid organic solvents) have a good chance of being introduced for everyday use. It is shown that waterborne nanodispers…

Surface Modification and SuperhydrophobicityMaterial Properties and Applications

A Novel Stepwise Degradation of Porphyrins. Synthesis and Structural Characterization ofmeso-Tetraphenylchlorophinato Nickel(II) andmeso-Tetraphenylsecochlorinato Nickel(II)

Christian Brückner、Ethan D. Sternberg、Jill K. MacAlpine 等 5 位作者1999-03-01Journal of the American Chemical Society

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTA Novel Stepwise Degradation of Porphyrins. Synthesis and Structural Characterization of meso-Tetraphenylchlorophinato Nickel(II) and meso-Tetraphenylsecochlorinato Nickel(II)Christian Brückner, Ethan D. Sternberg, Jill K. MacAlpine, Steven J. Rettig, and David Dolphin…

Molecular Sensors and Ion DetectionPorphyrin and Phthalocyanine ChemistryLuminescence and Fluorescent Materials

First Magnetic Observation of a Spin Crossover in a Langmuir-Blodgett Film

Hélène Soyer、E. Dupart、Carlos J. Gómez‐García 等 5 位作者1999-03-01Advanced Materials

That the Langmuir–Blodgett (LB) techniqueallows molecules to pack and orient in a well-defined fashion along a surface lends it suitability for preparing films of compounds with useful magnetic properties. Here is reported the synthesis of a semi-fluorinated iron complex (see Figure) that is extremely stable in the LB…

Photosynthetic Processes and MechanismsMagnetism in coordination complexesSpectroscopy and Quantum Chemical Studies

SAXS/WAXS study of the annealing process in quenched samples of isotactic poly(propylene)

Antonino Martorana、Stefano Piccarolo、Diana Sapoundjieva1999-03-01Macromolecular Chemistry and Physics

The structural rearrangement in samples of quenched isotactic poly(propylene) (iPP) submitted to different annealing treatments has been studied using simultaneous small- and wide-angle X-ray scattering (SAXS/WAXS) at the synchrotron radiation source of DESY, Hamburg. From a quantitative analysis of the WAXS profiles…

Polymer crystallization and propertiesPolymer Nanocomposites and PropertiesFiber-reinforced polymer composites

Purification and Characterization of Gentisate 1,2-Dioxygenases from Pseudomonas alcaligenes NCIB 9867 and Pseudomonas putida NCIB 9869

Yongmei Feng、Hoon Eng Khoo、Chit Laa Poh1999-03-01Applied and Environmental Microbiology

Two 3-hydroxybenzoate-inducible gentisate 1,2-dioxygenases were purified to homogeneity from Pseudomonas alcaligenes NCIB 9867 (P25X) and Pseudomonas putida NCIB 9869 (P35X), respectively. The estimated molecular mass of the purified P25X gentisate 1, 2-dioxygenase was 154 kDa, with a subunit mass of 39 kDa. Its struc…

Advanced Polymer Synthesis and Characterizationbiodegradable polymer synthesis and propertiesLanthanide and Transition Metal Complexes

On the mechanism of the paramagnetic-to-ferromagnetic transition in Fe-Al

Y. Yang、Ian Baker、Pedro Luis Martín1999-03-01Philosophical Magazine B

Single crystals of Fe-40 at.% Al were cold rolled to a variety of strains up to 48%, when cracking occurred. The rolled crystals were heated at 10 K min−1 to 973 K in a differential scanning calorimeter, whereupon three exothermic peaks were observed. The cold rolling also induced a transition from paramagnetism to fe…

Microstructure and mechanical propertiesMetallic Glasses and Amorphous AlloysIntermetallics and Advanced Alloy Properties

Intermediate Range Order and Bonding Character in Disordered Network-Forming Systems

Carlo Massobrio、Alfredo Pasquarello、Roberto Car1999-03-01Journal of the American Chemical Society

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTIntermediate Range Order and Bonding Character in Disordered Network-Forming SystemsCarlo Massobrio, Alfredo Pasquarello, and Roberto CarView Author Information Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), 23 rue du Loess F-67037 Strasbourg, F…

Advanced Chemical Physics StudiesMachine Learning in Materials ScienceSurface Chemistry and Catalysis

Hydrogen-Bonding Cavities about Metal Ions: A Redox Pair of Coordinatively Unsaturated Paramagnetic Co-OH Complexes

B.S. Hammes、Victor G. Young、A. S. Borovik1999-03-01Angewandte Chemie International Edition

Nature uses hydrogen bonds to regulate a variety of metal-based reactions. These effects are emulated in the stabilization of trigonal-bipyramidal, paramagnetic Co-OH complexes such as the mono- or dianionic redox-active complex 1 by use of a new hydrogen-bonding ligand.

Magnetism in coordination complexesPorphyrin and Phthalocyanine ChemistryCatalysis and Oxidation Reactions

Dynamic heterogeneities of translational and rotational motion of a molecular glass former from computer simulations

J. Qian、Reinhard Hentschke、Andreas Heuer1999-03-01The Journal of Chemical Physics

We employ classical molecular dynamics simulations to study the rotational and translational dynamics of propylene carbonate. The homogeneous and heterogeneous contributions to the nonexponential relaxation are studied. The non-Gaussian parameter is found to be strongly correlated with the degree of heterogeneity. Fur…

Phase Equilibria and ThermodynamicsMaterial Dynamics and PropertiesThermodynamic properties of mixtures

Low-temperature diagenetic illite-smectite in Lower Cambrian clays in North Estonia

Kalle Kirsimäe、P. Jøgensen、Volli Kalm1999-03-01Clay Minerals

Abstract Early Cambrian sediments on the East European platform in North Estonia, represented mostly by clays and silty clays, were deposited under normal marine conditions. The sediments were never affected by significant tectonic or thermal events after sedimentation 530 Ma ago, and the clays still have high water c…

Geological and Geochemical AnalysisPaleontology and Stratigraphy of FossilsClay minerals and soil interactions

Shock wave–inertial microbubble interaction: Methodology, physical characterization, and bioeffect study

Pei Zhong、Haifan Lin、Xufeng Xi 等 5 位作者1999-03-01The Journal of the Acoustical Society of America

A method of generating in situ shock wave-inertial microbubble interaction by a modified electrohydraulic shock wave lithotripter is proposed and tested in vitro. An annular brass ellipsoidal reflector (thickness = 28 mm) that can be mounted on the aperture rim of a Dornier XL-1 lithotripter was designed and fabricate…

Ultrasound and Hyperthermia ApplicationsCombustion and Detonation ProcessesUltrasound and Cavitation Phenomena

Modeling of dielectric relaxation spectra of polymers in the condensed phase

D.K. Das-Gupta、P.C.N. Scarpa1999-03-01IEEE Electrical Insulation Magazine

Discusses models and their possible implication in the interpretation of the relaxation spectra of polymers, particularly involving the concept of order/disorder systems. Furthermore, some examples of the application of the Dissado-Hill model have been provided in this work to explain quasi-dc (QDC) conduction process…

Advanced Sensor and Energy Harvesting MaterialsHigh voltage insulation and dielectric phenomenaDielectric materials and actuators