Nguyen T. H. Ha、Kiyohisa Fujimori、Ian E. Craven1997-11-01Macromolecular Chemistry and Physics
Abstract The monomer unit triad sequence distribution and the cis/trans linkage configurations at the cyclic maleic anhydride (MA) units in the copolymers of styrene (ST) and MA prepared in CCl 4 with AIBN at 50°C were quantitatively determined by 13 C DEPT NMR spectroscopy. So much as 61 % of the linkages at the MA u…
Polymer crystallization and propertiesSynthetic Organic Chemistry MethodsSynthesis and properties of polymers
James M. Pickard、E. Grant Jones1997-11-01Energy & Fuels
Experiments on the kinetics of O 2 depletion in air-saturated (65 ppm O 2 ) Jet-A (POSF-2827) fuel containing 4 ppm Fe 2 O 3 were conducted with a near-isothermal flowing test rig (NIFTR) using passivated heat-exchanger tubing over the range 418−468 K. The kinetic data are consistent with an oxidation mechanism involv…
Catalytic Processes in Materials SciencePetroleum Processing and AnalysisHeat transfer and supercritical fluids
P. Armand、Alain Ibanez、J. M. Tonnerre 等 5 位作者1997-11-01Physical review. B, Condensed matter
Germanium and silver atomic surroundings of ${\mathrm{Ag}}_{2}{\mathrm{GeS}}_{3}$ glass have been studied by anomalous wide-angle x-ray scattering. The structural parameters deriving from the simulations of the differential distribution functions, characterizing selectively Ge and Ag environments, show that the medium…
Material Dynamics and PropertiesGlass properties and applicationsPhase-change materials and chalcogenides
M.A. Chesters、K. J. Packer、Helen E. Viner 等 4 位作者1997-11-01The Journal of Physical Chemistry B
Hydrogen adsorption on a Cu/MgO catalyst is investigated using in situ 1 H NMR. The adsorption is largely homogeneous, demonstrating reasonable agreement with the Langmuir isotherm and only small variations in the frequency shift and spin−lattice relaxation time with increasing coverage. The catalyst is investigated u…
Advanced Chemical Physics StudiesHydrogen Storage and MaterialsQuantum, superfluid, helium dynamics
Carrie R. Lorenz、Howard D. Dewald、Frederick R. Lemke1997-11-01Electroanalysis
Abstract Cyclic voltammetry was used to characterize the oxidation‐reduction behavior of a series of novel hexacoordinate silicon(IV) porphyrin complexes. Each (Por)SiX 2 [Por = the dianions of the porphyrins: tetrakis( p ‐tolyl)porphyrin (TTP), tetraphenylporphyrin (TPP), tetrakis( p ‐trifluoromethylphenyl)porphyrin…
Photosynthetic Processes and MechanismsPorphyrin and Phthalocyanine ChemistryMetal-Catalyzed Oxygenation Mechanisms
Herschel M. Marchman1997-11-01Journal of Vacuum Science & Technology B Microelectronics and Nanometer Structures Processing Measurement and Phenomena
The mean value of a measurement set with precision σ has an offset relative to an accepted standard. Calibration of an instrument involves subtracting the offset between the mean value and the reference. Unfortunately, imaging characteristics for most types of microscopes are not constant. Slight changes in feature wa…
Advancements in Photolithography TechniquesElectron and X-Ray Spectroscopy TechniquesSurface Roughness and Optical Measurements
A. S. Morse、Helen F. Gleeson、S. Cummings1997-11-01Liquid Crystals
Small angle time-resolved X-ray diffraction was used to monitor the behaviour of the smectic layers during the electric field induced planar to homeotropic transition in a smectic A cell possessing a chevron layer geometry. The liquid crystal material used was S3, from Merck Ltd, and was sandwiched in a 15 mum paralle…
Liquid Crystal Research AdvancementsPlant and animal studiesPlant Reproductive Biology
David Gordon Page、S. Roy1997-11-01Journal de Physique IV (Proceedings)
Cu-Zn alloys have been electrodeposited from a pyrophosphate electrolyte containing Cu 2 P20 7> Zn 2 P 2 0 7 salts and an excess of K4P2O7 and KN0 3 . Current-potential data for both copper and zinc, as well their plating current efficiencies were determined from electrochemical polarisation experiments. Copper deposi…
Electrodeposition and Electroless CoatingsNanoporous metals and alloys
B. Guillot、Y. Guissani1997-11-01Molecular Simulation
The vibrational spectra (inelastic neutron scattering, infrared absorption and Raman scattering) of fused silica in the amorphous and in the liquid state are investigated by molecular dynamics simulation in using the TTAM interionic potential (Tsuneyuki et al., Phys. Rev. Lett., 61, 869 (1988)). The simulation predict…
High-pressure geophysics and materialsMaterial Dynamics and PropertiesGlass properties and applications
J. de Groot、Johan G. Hollander、J. De Bleijser1997-11-01Macromolecules
The tacticity of poly(maleic acid) has been resolved by 150-MHz 13 C NMR spectroscopy in 0.1 N HCl solution at 60 °C by using the chemical shifts from the backbone carbon atoms and the carboxyl carbon atoms. The racemic propagation is found to be preferred by a factor 2 over mesomeric propagation. The resonances of th…
Polymer crystallization and propertiesPolymer Nanocomposites and Propertiesbiodegradable polymer synthesis and properties
Erwin Reichardt1997-11-01Diatom Research
In this paper the morphology of 10 seldom reported and insufficiently known diatoms from the old catch-all genus Navicula (excl. Navicula sensu stricto) are described based on LM and, in particular, SEM investigations. For most of them SEM micrographs are presented for the first time. It is shown that some of these di…
Analytical chemistry methods developmentMinerals Flotation and Separation TechniquesDiatoms and Algae Research
Andreas Sonntag1997-11-01American Ceramic Society bulletin
Silicon carbide kiln furniture systems are an essential part of modern high-temperature technology. SiC ceramics have exceptional high-temperature stability and thermal shock resistance., They show no plastic deformation (creep) under mechanical load and maintain their geometry after each high-temperature cycle. There…
Advanced ceramic materials synthesisRecycling and utilization of industrial and municipal waste in materials production
M. Pape、K. Hiltrop1997-11-01Molecular crystals and liquid crystals science technology. Section A, Molecular crystals and liquid crystals/Molecular crystals and liquid crystals science and technology. Section A, Molecular crystals and liquid crystals
The twisting power of several chiral dopants in two host phase classes is investigated under the viewpoint of its dependence on chain length and size of the headgroups of the surfactants. The results are explained qualitatively, using a simple model of intramicellar chiral induction, which is sensitive to flexibilitie…
Liquid Crystal Research AdvancementsSurfactants and Colloidal SystemsSpectroscopy and Quantum Chemical Studies
Shuichi Arakawa、Kenji Mogi、Koichi Kikuta 等 7 位作者1997-11-01Journal of the American Ceramic Society
Oriented (Ti,Sn)O 2 thin films with modulated microstructure were successfully synthesized on sapphire substrates by using sol–gel processing combined with spinodal decomposition. The degree of orientation of (Ti 0.5 Sn 0.5 )O 2 thin films increased in the following order: sapphire (0001), (110), and (012). (Ti 0.5 Sn…
ZnO doping and propertiesSemiconductor materials and devicesSolidification and crystal growth phenomena
B. Rubio、F. Gil‐Sotres1997-11-01Communications in Soil Science and Plant Analysis
The potassium (K) status of a group of Galician natural soils was evaluated, and the equilibria between the four main K forms were examined. The results indicated that the Galician soils studied contained a large mineral K fraction (97% of total K), and a smaller fraction of labile K forms, composed of non‐exchangeabl…
Soil and Unsaturated FlowClay minerals and soil interactionsIron oxide chemistry and applications
J. Y. Decker、A. Fernandez、Donald W. Sweeney1997-11-01Journal of Vacuum Science & Technology B Microelectronics and Nanometer Structures Processing Measurement and Phenomena
We show that by using interference lithography coupled with image reversal techniques we can generate resist structures ranging from one-dimensional gratings to two-dimensional arrays of posts and holes. These resist structures have high aspect ratios and nearly vertical sidewalls. The structure dimensions are accurat…
Advancements in Photolithography TechniquesOptical Coatings and GratingsNear-Field Optical Microscopy
Mark B. Edlund、Lynn A. Brant1997-11-01Diatom Research
Frustulia bahlsii sp. nov. is formally described from soft-water sites from Maine to North Carolina along the eastern United States. The new species is separated from other members of the genus by the following suite of characters: large size, spatulate terminal raphe ends (i.e. not provided with a “porte-crayon”), an…
Aquatic Ecosystems and Phytoplankton DynamicsDiatoms and Algae Research
L. Wulff、Hk. Müller‐Buschbaum1997-11-01Zeitschrift für Naturforschung B
Abstract The new compound SrCuTe 2 O 6 has been prepared by quenching single crystals grown from a flux of SrCO 3 , TeO 2 and CuCO 3· Cu(OH) 2 . X-ray investigations show cubic symmetry, space group O 7 -P4 1 32, lattice constant a = 12.473(1), Z = 12. The crystal structure is characterized by square planar CuO 4 poly…
Crystal Structures and PropertiesAdvanced Condensed Matter PhysicsInorganic Fluorides and Related Compounds
Tetsuo Ohta、Huyue Zhang、Yoshitaka Torihara 等 4 位作者1997-11-01Organic Process Research & Development
In the synthesis of dexamethasone acetate from tigogenin, the introduction of the 17α-hydroxy-16α-methyl and the 1,4-diene moieties was improved. For the introduction of the 17α-hydroxy-16α-methyl moiety, the key step, epoxidation, was accomplished in high yield with peracetic acid in a buffer solution of sodium aceta…
Natural product bioactivities and synthesisPhytochemical Studies and BioactivitiesPhytochemistry and Bioactive Compounds
Jong K. Lee1997-11-01International Materials Reviews
The shapes, sizes, and distribution of second phase precipitates are the principal factors determining the mechanical, electrical, and magnetic properties of a wide variety of high technology alloys and ceramics. In the initial processing, and also in high temperature applications, such as jet engine superalloys, the…
Microstructure and mechanical propertiesAluminum Alloy Microstructure PropertiesHigh Temperature Alloys and Creep