Materials Literature
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。
The alpha process (segmental motion) of thin polystyrene films supported on glass substrate has been investigated in a wider frequency range from 10(-3) Hz to 10(4) Hz using dielectric relaxation spectroscopy and thermal expansion spectroscopy. The relaxation rate of the alpha process increases with decreasing film th…
We report bcc-like crystal structures in 2-4 ML Fe films grown on fcc Cu(100) using scanning tunneling microscopy. The local bcc structure provides a straightforward explanation for their frequently reported outstanding magnetic properties, i.e., ferromagnetic ordering in all layers with a Curie temperature above 300…
The influence of mechanical strain on the critical current (Ic) is investigated for MgB2/stainless steel (SUS316) superconducting tapes. The tapes are fabricated by using 'powder in tube' method and deformation process without any heat treatment. The tensile axial strain along tape length is successfully induced to th…
First-principles full-potential linearized augmented plane wave (FLAPW) calculations are performed to clarify the role of the interface geometry on piezoelectric fields and on potential line-ups at the [0001]-wurtzite and [111]-zincblende GaN/Al junctions. The electric fields (polarity and magnitude) are found to be s…
We demonstrate that at the usual 1E-7 torr range of base pressures in the sputtering chamber, X-ray photoelectron spectroscopy shows the existence of a thin AlOx layer at the Nb/Al interface in both Nb/Al-AlOx/Pb tunnel junctions and Nb/Al bilayers. This is due to the time elapsed between the deposition of the Nb and…
The rodlike microcrystal suspension prepared by sulfuric acid hydrolysis of bacterial cellulose was found to undergo spontaneous nematic phase separation after complete desalination. This phase separation was preceded by a birefringent glassy-like state for about 1 week. Addition of trace electrolyte (<1 mM NaCl) caus…
The paper reports the synthesis of the first-row transition metal hexaethylporphodimethene derivatives [(Et6N4)M] [M=Mn, 3; M=Co, 5; M = Cu, 7] on a multigram scale, which makes them easily available for reactivity studies. After synthesis they were converted into the corresponding five-coordinate [(Et6,N4)M(L)] [M =…
The dynamic structure factor of cubic boron nitride has been measured using nonresonant inelastic x-ray scattering. The experimental data are compared with the results of a recently developed ab initio calculation scheme, which takes into account the interaction between the excited electron and the hole. The agreement…
Crystalline SiGe alloy sheet polymers were topotactically prepared from epitaxially grown calcium germanosilicide Ca(Si1−xGex)2 precursor films in the whole composition range. These polygermanosilynes are found to be a well-defined mixture of the known siloxene and polygermyne sheet polymers with the OH groups exclusi…
The interaction of phonon states with the point, line, and plane defects is considered near the edge of an optical-phonon branch. Because the effect of disorder on optical phonons is ordinarily studied in the Raman experiments, we calculate the averaged phonon Green's function characterizing the Raman line shape. Ther…
Mit dem organischen Segment konjugiert ist die Mo≡N-Bindung in den neuartigen molekularen organisch-anorganischen Hybridmaterialien, die durch Pd-katalysierte Kupplung eines iodfunktionalisierten Hexamolybdatanions und eines Alkins erhalten wurden (siehe Schema; Ar=4-Methylphenyl, 3,5-Di(tert-butyl)phenyl). Die Wechse…
The effect of an exchange field on the electrical transport in thin films of metallic ferromagnetic manganites has been investigated. The exchange field was induced both by direct exchange coupling in a ferromagnet/antiferromagnet multilayer and by indirect exchange interaction in a ferromagnet/paramagnet metallic sup…
Representative metal complexes of a biconcave D4-symmetric porphyrin were synthesised by metalion insertion into the porphyrin ligand 1. The NMR spectra suggested D4-symmetry for the ZnII and dioxo-RuVI complexes of 1 and C4-symmetry for the unsymmetrically ligated RuII and RhIII complexes. Metal complexes of 1 proved…
Wetting of the Sigma = 5 (310) <001> symmetrical tilt grain boundary (GB) close to the solubility limit in the Cu(Ag) solid solution has been observed by means of Monte Carlo simulations at T = 600 K. More precisely, a finite thickness film almost pure in Ag, separating the two initial Cu(Ag) grains, can be obtained f…
Mid-infrared pump-probe measurements with subpicosecond time resolution reveal the existence of a metastable condensed phase of the electron-hole ensemble in a direct-gap semiconductor CuCl. High-density electrons and holes are directly created in a low-temperature state by the resonant femtosecond excitation of excit…
The nucleation and growth of carbon nanotubes assisted by microwave plasma on metal surfaces have been observed by transmission electron microscopy. Microwave plasma generated nanoparticles of various sizes on metal surfaces. Initially, the nanoparticles were embedded in an amorphous carbon layer and led to the format…
The dielectric loss in amorphous, thin-film oxide insulators produces a real part of the ac conductivity σ′(ω) that scales as ωs with s∼1. Conventional models explain this frequency dependence by hopping or tunneling of charge between neighboring defect sites. These models fail at low temperatures since they predict t…
Eine stabile Organokupfer(II)-Verbindung mit einem einfach N-invertierten Calix[4]phyrin als C-Ligand wurde synthetisiert und durch eine Röntgenstrukturanalyse charakterisiert (siehe Bild). Für die Bildung der Metall-Kohlenstoff-Bindung erwies sich eine vollständige π-Konjugation als nicht notwendig.
High diffraction efficiencies have been achieved with polarization gratings recorded in thin films of an azobenzene side-chain liquid crystalline polyester by means of biphotonic processes. Efficiency values up to 30% have been reached after an induction period of 300 s and subsequent evolution with the sample in dark…
We use the anomalous x-ray diffraction technique to investigate the nature of the tantalum displacement pattern in the modulated phase of the charge-density-wave compound (TaSe4)2I. In addition to the known acousticlike modulation, we find the first direct evidence for the condensation of opticlike Ta displacements al…