Song‐Ling Jia、Walter Jentzen、Mayou Shang 等 7 位作者1998-07-31Inorganic Chemistry
Axial ligation of nickel(II) 5,10,15,20-tetraphenylporphyrin (NiTPP) with pyrrolidine or piperidine has been investigated using X-ray crystallography, UV-visible spectroscopy, resonance Raman spectroscopy, and molecular mechanics (MM) calculations. By varying the pyrrolidine concentration in dichloromethane, distinct…
Metal complexes synthesis and propertiesPorphyrin and Phthalocyanine ChemistryPhotochemistry and Electron Transfer Studies
Č. Burdík、Ch Frougny、Jean‐Pierre Gazeau 等 4 位作者1998-07-31Journal of Physics A Mathematical and General
Recently, discrete sets of numbers, the -integers , have been proposed as numbering tools in quasicrystalline studies. Indeed, there exists a unique numeration system based on the irrational in which the -integers are all real numbers with no fractional part. These -integers appear to be quite appropriate for describi…
Quasicrystal Structures and PropertiesMineralogy and Gemology Studies
A. Kay、Elke Arenholz、Sungkwang Mun 等 8 位作者1998-07-31Science
Measurements and theoretical calculations are reported for an interatomic multi-atom resonant photoemission (MARPE) effect that permits direct determination of near-neighbor atomic identities (atomic numbers). MARPE occurs when the photon energy is tuned to a core-level absorption edge of an atom neighboring the emitt…
X-ray Spectroscopy and Fluorescence AnalysisElectron and X-Ray Spectroscopy TechniquesElectronic and Structural Properties of Oxides
Hans Rogl、Kirstin Kosemund、Werner Kühlbrandt 等 4 位作者1998-07-31FEBS Letters
Two distinctly different membrane proteins, which produced inclusion bodies in Escherichia coli, have been refolded to reconstitute properties appropriate to their native counterparts. The method employed utilises nickel chelating chromatography, where the solubilised inclusion bodies bind, refold and elute. Our aims…
Bacterial Genetics and BiotechnologyRNA and protein synthesis mechanismsEnzyme Structure and Function
Masaki Kogiso、Satomi Ohnishi、Kiyoshi Yase 等 5 位作者1998-07-31Langmuir
A new family of oligopeptide-based bolaamphiphiles, glycylglycine- ( 1a − h ), glycylglycylglycine- ( 2a − b ), sarcosylsarcosine- ( 3 ), l -prolyl- l -proline- ( 4 ), glycylsarcosylsarcosine- ( 5 ), and glycyl- l -prolyl- l -proline ( 6 )-based bolaamphiphiles with a dicarboxylic headgroup at each end, has been synth…
Supramolecular Chemistry and ComplexesChemical Synthesis and AnalysisSupramolecular Self-Assembly in Materials
Martin Fuchs、Matthias Scheffler1998-07-31arXiv
The package fhi98PP allows one to generate norm-conserving pseudopotentials adapted to density-functional theory total-energy calculations for a multitude of elements throughout the periodic table, including first-row and transition metal elements. The package also facilitates a first assessment of the pseudopotential…
Materials Science
Steven C. Erwin、Hanno H. Weitering1998-07-31arXiv
First-principles electronic-structure methods are used to study a structural model for Ag/Si(111)3x1 recently proposed on the basis of transmission electron diffraction data. The fully relaxed geometry for this model is far more energetically favorable than any previously proposed, partly due to the unusual formation…
Materials Science
Michael S. Nashner、Anatoly I. Frenkel、David M. Somerville 等 6 位作者1998-07-31Journal of the American Chemical Society
The reductive condensation of a carbon-supported molecular cluster precursor, PtRu 5 C(CO) 16, into a bimetallic nanoparticle has been followed by using in situ extended X-ray absorption fine structure spectroscopy, temperature-programmed desorption, and scanning transmission electron microscopy. The data reveal that…
Electrocatalysts for Energy ConversionCatalytic Processes in Materials ScienceQuantum Dots Synthesis And Properties
Wenhui Li、Harald D. H. Stöver1998-07-30Journal of Polymer Science Part A Polymer Chemistry
The precipitation polymerization of commercial divinylbenzene in acetonitrile containing up to 40 vol. % toluene or other cosolvents is shown to produce novel porous monodisperse poly(divinylbenzene) microspheres. These microspheres have diameters between 4 and 7 μm, total pore volumes of up to 0.52 cm3/g, and surface…
Mesoporous Materials and CatalysisMembrane Separation and Gas TransportCovalent Organic Framework Applications
Peter P. Chu、Hew-Der Wu、Chih-Tsung Lee1998-07-30Journal of Polymer Science Part B Polymer Physics
The thermodynamic properties of novolac type phenolic resin blended with poly(ethylene oxide) (PEO) were investigated by the Painter–Coleman association model (PCAM). Equilibrium constants and enthalpy corresponding to the interaction between phenolic and poly(ethylene oxide) were calculated from the Fourier transform…
Polymer crystallization and propertiesEpoxy Resin Curing ProcessesSynthesis and properties of polymers
Songlin Liu、Tai‐Shung Chung、Lining Lu 等 6 位作者1998-07-30Journal of Polymer Science Part B Polymer Physics
We have studied the nonisothermal and isothermal crystallization kinetics of an aromatic thermotropic liquid crystalline polyimide synthesized from 1,2,4,5-benzenetetracarboxylic dianhydride (PMDA) and 1,3-bis[4-(4′-aminophenoxy) cumyl] benzene (BACB) by means of differential scanning calorimetry (DSC). Polarized ligh…
Liquid Crystal Research AdvancementsEpoxy Resin Curing ProcessesSynthesis and properties of polymers
Jinsheng Wang、Yoshinori Kamiya、Yasutoshi Naito1998-07-30Journal of Polymer Science Part B Polymer Physics
Sorption, dilation, and diffusion behaviors were studied for the system of polysulfone/CO2 with regard to the effects of CO2 conditioning, i.e., exposure to high-pressure CO2. Concurrent measurements of solubility, dilation, and diffusivity were performed for polysulfone films before and after the conditioning at 25 a…
Polymer crystallization and propertiesMembrane Separation and Gas TransportPolymer Foaming and Composites
I. Alig、S. Tadjbakhsch、A. Zosel1998-07-30Journal of Polymer Science Part B Polymer Physics
An ultrasonic shear wave reflection method was applied to study film formation and temperature dependence of the complex shear modulus (G*G′ + iG″) in different amorphous films made of aqueous dispersions of acrylic-type copolymers. The data are compared with dynamic-mechanical measurements in the low frequency range…
Material Dynamics and PropertiesPolymer Nanocomposites and PropertiesRheology and Fluid Dynamics Studies
Munetaka Oyama、Richard D. Webster、Marco F. Suárez 等 6 位作者1998-07-30The Journal of Physical Chemistry B
The effect of aggregation of Mg 2+ or Ba 2+ (M 2+ ) and electrochemically generated reduced forms of 7,7,8,8-tetracyanoquinodimethane (TCNQ) in acetonitrile solution was studied by voltammetric and chronoamperometric techniques, the electrochemical quartz crystal microbalance (EQCM), ESR spectroscopy, and atomic force…
Molecular Junctions and NanostructuresElectrochemical Analysis and ApplicationsOrganic and Molecular Conductors Research
Rainer Glaser、Grace Shiahuy Chen1998-07-30Journal of Computational Chemistry
Asymmetric donor–acceptor-substituted π-conjugated systems with low dipole moments and structural components that favor parallel alignment of neighboring molecules are potential molecular organic materials with nonlinear optical properties for which near prefect dipole parallel alignment is possible. The asymmetrical…
Crystallography and molecular interactionsNonlinear Optical Materials ResearchOrganic and Molecular Conductors Research
Elisabeth Prasman、Edwin L. Thomas1998-07-30Journal of Polymer Science Part B Polymer Physics
Films of a blend of styrene–isoprene triblock copolymer and mineral oil have been simple-cast and roll-cast from a toluene solution. Their microstructure has been analyzed by transmission electron microscopy and small-angle X-ray scattering. The blend formed polystyrene spheres arranged on a body-centered cubic lattic…
Polymer crystallization and propertiesPolymer Nanocomposites and PropertiesPolymer composites and self-healing
Hong Gyun Kim、Richard E. Robertson1998-07-30Journal of Polymer Science Part B Polymer Physics
The melting behavior of poly(butylene terephthalate) crystallized isothermally for various times was examined using differential scanning calorimetry. After short crystallization times, the DSC analysis gave two melting peaks, but after longer times, the analysis gave three peaks. The latter triplet of DSC peaks can b…
Polymer crystallization and propertiesbiodegradable polymer synthesis and propertiesMicroplastics and Plastic Pollution
Nobuhiro Kawatsuki、Hirohumi Takatsuka、Tohei Yamamoto 等 4 位作者1998-07-30Journal of Polymer Science Part A Polymer Chemistry
Linearly polarized (LP) UV photoreaction of a photo-crosslinkable side-chain liquid-crystalline polymer (SLCP) containing photoreactive cinnamoyl and biphenyl mesogenic groups (1) was studied. The optical anisotropy of the polymer film was induced by the LP-UV photoreaction and was investigated by the temperature-cont…
Liquid Crystal Research AdvancementsSemiconductor Lasers and Optical DevicesSynthesis and properties of polymers
Franco Sannicolò、Elisabetta Brenna、Tiziana Benincori 等 7 位作者1998-07-30Chemistry of Materials
Functionalized cyclopentadithiophenes 2 and 3 were synthesized and polymerized by anodic coupling, in acetonitrile solution, in the presence of 0.1 M tetraethylammonium perchlorate as supporting electrolyte. The former carries a 16-crown-5-ether ring coplanar to the bithiophene moiety, while a perpendicular 15-crown-5…
Conducting polymers and applicationsElectrochemical Analysis and ApplicationsAnalytical Chemistry and Sensors
Wen Zhou、Jian Hua Dong、Kun Yun Qiu 等 4 位作者1998-07-30Journal of Polymer Science Part A Polymer Chemistry
Poly(styrene-co-maleic anhydride)/silica hybrid material has been successfully prepared from styrene–maleic anhydride copolymer and tetraethoxysilane (TEOS) in the presence of a coupling agent (3-aminopropyl)triethoxysilane (APTES) by an in situ sol–gel process. It was observed that the gel time of sol–gel solution wa…
Polymer Nanocomposites and PropertiesMesoporous Materials and CatalysisSilicone and Siloxane Chemistry