Biwang Jiang、Szu-Wei Yang、Denis C. Barbini 等 4 位作者1998-01-01Chemical Communications
New linear conjugated porphyrin polymers are synthesized by a palladium-catalyzed cross-coupling reaction of [5,15- bis(ethynyl)-10,20-bis(mesityl)porphyrin]zinc and diiodobenzene derivatives; enhanced solubility of the conjugated porphyrin polymers is achieved by attachment of long alkyl ether or dialkyl amide groups…
Porphyrin and Phthalocyanine ChemistryLuminescence and Fluorescent MaterialsMetal-Catalyzed Oxygenation Mechanisms
R. Stöckel、Maren Stämmler、K. Janischowsky 等 6 位作者1998-01-01Journal of Applied Physics
The so-called bias pretreatment allows the growth of heteroepitaxial diamond films by plasma chemical vapor deposition on silicon (100) surfaces. We present plan-view and cross-sectional transmission electron micrographs of the substrate surface at different phases of the bias pretreatment. These observations are augm…
Metal and Thin Film MechanicsSemiconductor materials and devicesDiamond and Carbon-based Materials Research
Christopher T. Williams、Christos G. Takoudis、Michael J. Weaver1998-01-01The Journal of Physical Chemistry B
The relationship between surface speciation and catalytic activity/selectivity during methanol oxidation on polycrystalline rhodium under ambient-pressure flow-reactor conditions was studied from 25 to 500 °C by means of surface-enhanced Raman spectroscopy (SERS) along with parallel mass spectrometric (MS) measurement…
Electrocatalysts for Energy ConversionCatalytic Processes in Materials ScienceElectronic and Structural Properties of Oxides
K. Yaman、C. Jeppesen、Carlos M. Marques1998-01-01OpenAlex
We study the depletion interaction between spherical particles of radius R immersed in a dilute solution of rigid rods of length L. The computed interaction potential is, within numerical accuracy, exact for any value of L/R. In particular we find that for L ∼ R, the depth of the depletion well is smaller than the pre…
Material Dynamics and PropertiesSurfactants and Colloidal SystemsPickering emulsions and particle stabilization
Naoya Yoshida、Hitoshi Shimidzu、Atsuhiro Osuka1998-01-01Chemistry Letters
Abstract Meso-meso coupled diporphyrins were prepared from 5,10,15-trisubstituted zinc-porphyrins in high yields upon treatment with AgPF6 alone or with AgPF6 and I2.
Porphyrin and Phthalocyanine ChemistryLuminescence and Fluorescent MaterialsNeonatal Health and Biochemistry
Dan W. Urry1998-01-01Biopolymers
Peptide-based polymers can be transformable hydrogels, elastomers, regular thermoplastics, or inverse thermoplastics, and can function as diverse molecular machines. When of the appropriate composition, these polymers exhibit hydrophobic folding and assembly transitions in the accessible aqueous range as the temperatu…
Protein Structure and DynamicsChemical Synthesis and AnalysisSupramolecular Self-Assembly in Materials
B. Yang、Peter Townsend、Aled Rowlands1998-01-01Physical review. B, Condensed matter
Lanthanum fluoride consistently shows two strong thermoluminescence glow peaks at low temperature in pure material near 90 and 128 K. A model is proposed in which these thermoluminescence peaks arise from the annealing of halogen defect sites, similar to the $H$ and ${V}_{k}$ centers of the alkali halides. Relaxation…
Luminescence Properties of Advanced MaterialsInorganic Fluorides and Related CompoundsOptical properties and cooling technologies in crystalline materials
Franc Meyer、Katja Heinze、Bernhard Nuber 等 4 位作者1998-01-01Journal of the Chemical Society Dalton Transactions
Six dinuclear cobalt(II) complexes of pyrazolate ligands with multidentate chelating side arms {3,5-(R2NCH2)2C3N2H2; R2N = [Me2N(CH2)3]2N (HL1) or (Et2NCH2CH2)2N (HL2)} have been prepared and characterised. The reaction of L1 and L2 with 2 equivalents of [Co(MeCN)6][BF4]2 and NaBPh4 proceeds via the isolable compounds…
Metal complexes synthesis and propertiesMagnetism in coordination complexesLanthanide and Transition Metal Complexes
Joost N. H. Reek、Maxwell J. Crossley、Joost N. H. Reek 等 6 位作者1998-01-01Chemical Communications
Two rigid Tröger’s base dizinc(II) bis-porphyrin receptor molecules 1 and the first generation of dendrimer tetramine 4 form a 2:1 complex 5, a self-assembled spherical superstructure encapsulating the dendrimer.
Porphyrin and Phthalocyanine ChemistrySupramolecular Self-Assembly in MaterialsDendrimers and Hyperbranched Polymers
Bong-Ho Lee、Nam‐Kyoung Kim、Jeong-Joo Kim 等 4 位作者1998-01-01Ferroelectrics
The reaction sequences of B-site precursors and perovskite phase formation, crystallographic data, dielectric properties, and microstructures in the PFW-PFN system are reported. The formations of B-site precursors and perovskite phases were studied by X-ray diffraction. B-site precursors formed directly from the const…
Ferroelectric and Piezoelectric MaterialsAdvanced ceramic materials synthesisMicrowave Dielectric Ceramics Synthesis
Yasubumi Furuya、Nesbitt W. Hagood、Hisamichi Kimura 等 4 位作者1998-01-01Materials Transactions JIM
Rapidly solidified ferromagnetic shape memory Fe-29.6 at% Pd alloy was fabricated to develop a new type of actuator material responded to magnetic field. The thin ribbon samples which were made by the originally designed electro magnetically controlled nozzleless melt-spinning method showed stronger crystal anisotropy…
Microstructure and Mechanical Properties of SteelsShape Memory Alloy TransformationsMagnetic Properties and Applications
Reshef Tenne、Claude Lévy‐Clément1998-01-01Israel Journal of Chemistry
Abstract With their unique chemical stability and high electron mobility, boron‐doped thin diamond films are likely to have favorable properties for a number of electrochemical applications. A review of the recent developments in this field is presented with critical evaluation of the experimental data. In particular,…
Semiconductor materials and devicesDiamond and Carbon-based Materials ResearchElectronic and Structural Properties of Oxides
Gefeson Mendes Pacheco、Eric Zhao、A. García 等 5 位作者1998-01-01Journal of Materials Chemistry
Synthesis of mesoporous zirconia has been performed by slowly hydrolyzing zirconium propoxide in the presence of anionic surfactants: dodecyl phosphate or sulfate (P12 and Sf12) and hexadecyl sulfonate (So16). t-Plot surface areas >400 m2 g–1 and diffraction lines corresponding to spacings near 45 Å were measured for…
Catalytic Processes in Materials ScienceZeolite Catalysis and SynthesisMesoporous Materials and Catalysis
Shinichi Sakurai、Hiroshi Irie、Hideo Umeda 等 6 位作者1998-01-01Macromolecules
We report the morphology and phase behaviors of binary blends of polystyrene- block -polyisoprene (SI) copolymers, which were studied by a small-angle X-ray scattering (SAXS) technique. The neat SI copolymers employed in this study have almost the same molecular weights but different volume fractions of polystyrene bl…
Polymer crystallization and propertiesRheology and Fluid Dynamics StudiesBlock Copolymer Self-Assembly
Norikazu Nishiyama、Akihiro Koide、Yasuyuki Egashira 等 4 位作者1998-01-01Chemical Communications
A mesoporous MCM-48 membrane with high thermal stability has been synthesized on a porous stainless steel support by hydrothermal treatment.
Catalytic Processes in Materials ScienceMesoporous Materials and CatalysisNanomaterials for catalytic reactions
Anthony C. Jones、Timothy J. Leedham、P.J. Wright 等 8 位作者1998-01-01Journal of Materials Chemistry
The new precursors [Ti(OPri)3(OCH2CH2NMe2)] 1 and [Ti(OPri)2(OCH2CH2NMe2)2] 2 have been prepared and characterised. Compound 1 exists in solution at room temperature as a mixture of monomer and dimer(s), however at elevated temperatures the monomer predominates. Compound 2 exists in solution predominantly as a monomer…
Ferroelectric and Piezoelectric MaterialsSemiconductor materials and devicesElectronic and Structural Properties of Oxides
G. Allodi、R. De Renzi、G. Guidi1998-01-01Physical review. B, Condensed matter
We present ${}^{139}\mathrm{La}$ NMR experiments on five powder samples of lanthanum manganites, with a ${\mathrm{Mn}}^{4+}$ concentration ranging from the antiferromagnetic-insulator (AFM) to the ferromagnetic-conducting (FM) region of the phase diagram. We measure a positive hyperfine coupling $\mathcal{C}=0.13 \mat…
Magnetic and transport properties of perovskites and related materialsRare-earth and actinide compoundsAdvanced Condensed Matter Physics
Hiizu Iwamura、Katsuya Inoue、Noboru Koga1998-01-01New Journal of Chemistry
Bis- and tris(aminoxyl) radicals and di(4-pyridyl)diazomethane form crystalline complexes with extended structures upon reaction with [M(hfac)2] (M=MnII or CuII, and hfac=hexafluoroacetylacetonate). Organic 2p and metal 3d spins in these complexes order at 3.4–46 K depending on the dimensions of the extended structure…
Magnetism in coordination complexesLanthanide and Transition Metal ComplexesElectron Spin Resonance Studies
Stuart L. James、D. Michael P. Mingos、Andrew J. P. White 等 4 位作者1998-01-01Chemical Communications
In the presence of templating anions, 2:3 molar mixtures of triphos and silver(I) cations unexpectedly give novel hexanuclear cages, which result from an unusual ‘endo-methyl’ geometry of the triphos ligands.
Metal-Organic Frameworks: Synthesis and ApplicationsMagnetism in coordination complexesPorphyrin and Phthalocyanine Chemistry
Pascal Van Der Voort、Mark Morey、Galen D. Stucky 等 5 位作者1998-01-01The Journal of Physical Chemistry B
Pure silica MCM-48 is prepared by a novel synthesis method, using the [C 18 H 37 N + (CH 3 ) 2 −(CH 2 ) 12 −N + (CH 3 ) 2 C 18 H 37 ]·2Br - surfactant, abbreviated as GEMINI 18-12-18. The MCM-48, obtained after careful calcination, is a highly crystalline, mesoporous material with the characteristics of the Ia 3 d cub…
Catalytic Processes in Materials ScienceMesoporous Materials and CatalysisCatalysis and Oxidation Reactions