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。
Abstract Nanocomposites of organophilic montmorillonite (C18‐MMT), nitrile–butadiene rubber (NBR), and a coupling agent were produced during a melt compounding process at room temperature. During the process, it was clearly observed that organo‐MMT particles were exfoliated into nanoscale layers of approximately 1–30…
A report of progress in spintronics-related works involving group III nitrides is given emphasizing contradictory opinions concerning basics characteristics of these materials. The actual position of magnetic impurities in the GaN lattice as well as a possible role of magnetic precipitates is discussed. The question w…
A review is given of advances in the field of carrier-controlled ferromagnetism in Mn-based diluted magnetic semiconductors and their nanostructures. Experimental results for III-V materials, where the Mn atoms introduce both spins and holes, are compared to the case of II-VI compounds, in which the Curie temperatures…
Abstract Rubber compounds based on natural rubber (NR) reinforced with octadecylamine‐modified bentonite have been prepared via a vulcanization process and characterized by several techniques. The silicate nanolayers are exfoliated and uniformly dispersed in the polymer chains. Monsanto measurements have shown that th…
Abstract Bicomponent sheath‐core fibers were prepared by a general melt‐spinning method with polypropylene chips and silver nanoparticles. The melt‐spun fibers were characterized by DSC, WAXS and SEM. The antibacterial effect was evaluated by an AATCC 100 test, a quantitative method. The results of the DSC thermogram…
Parallelism of tight-binding molecular dynamics simulations is presented by means of the order-N electronic structure theory with the Wannier states, recently developed (J. Phys. Soc. Jpn. 69,3773 (2000)). An application is tested for silicon nanocrystals of more than millions atoms with the transferable tight-binding…
The effects of long-range anisotropic elastic deformations on electronic structure in superconductors are analyzed within the framework of the Bogoliubov-de Gennes equations. Cases of twin boundaries and isolated defects are considered as illustrations. We find that the superconducting order parameter is depressed in…
We present a theoretical study of the infrared magneto-optical properties of ferromagnetic (III,Mn)V semiconductors. Our analysis combines the kinetic exchange model for (III,Mn)V ferromagnetism with the Kubo linear response theory and the Born approximation estimates for the effect of disorder on the valence-band qua…
A vacancy defect is described by a Frenkel--Kontorova model with a discommensuration. This vacancy can migrate when interacts with a moving breather. We establish that the width of the interaction potential must be larger than a threshold value in order that the vacancy can move forward. This value is related to the e…
The presence of a domain wall trapped by a sub-micron notch is probed in two ways: through electronic transport measurements and by Magnetic Force Microscopy (MFM). We observe complex magnetic features which are consistent with numerical simulations predicting the existence of multiple magnetic configurations stabiliz…
We present powder and single-crystal x-ray diffraction data as evidence for a monoclinic distortion in the low-spin $(S=0)$ and intermediate spin states $(S=1)$ of ${\mathrm{LaCoO}}_{3}.$ The alternation of short and long bonds in the ab plane indicates the presence of ${e}_{g}$ orbital ordering induced by a cooperati…
Wide-band-gap semiconductor-doped-glasses were obtained by synthesizing SnO<sub>2</sub>:SiO<sub>2</sub> nanostructured glassceramics. In this binary system, comprising two chemically compatible oxides, crystalline SnO2 nanoclusters were embedded in a pure silica matrix in a controlled way, by setting appropriate therm…
Glasses belonging to the CaO−ZrO 2 −SiO 2 ternary system were prepared by melting raw materials at 1600 °C. Several properties of the glassy materials, such as density and thermal behavior, were experimentally determined, and the results were interpreted by comparison with the structural information derived from molec…
A numerically stable and systematic implementation of the rigorous coupled-wave analysis (RCWA) for the general multilayered grating structures is presented for both TE and TM modes. Numerical results of the approach are shown for the diffraction-based optical device as an example and are compared with the scalar diff…
We have modified the conventional arc discharge method for the synthesis of high quality single-walled carbon nanotube (SWNT) silks with high purity (over 70%) by using a hollow cathode that can collect SWNTs effectively. Characterizations of these SWNT materials by XRD, UV−vis−near-IR, Raman were taken. Finally a sim…
Results are presented for a study on the influence of molecular and polymeric carboxylate-containing additives on the nucleation of CaCO 3 in solutions similar in ion composition and pH to those used in wood pulping operations. Investigated additives included aminocarboxylic acids, ethylenediaminetetraacetic acid and…
Leitend verbunden: Eine zentrale Tetrathiafulvalen(TTF)-Einheit vermittelt im abgebildeten Dichinon-Tetrathiafulvalen effektiv die elektronische Kopplung zwischen den Chinonfunktionen in der Peripherie. Es erfolgt schrittweise Einelektronenreduktion; die Potentialdifferenz zwischen den Reduktionsschritten zeigt, dass…
Dihydroxyacetone (Dha) kinases are homologous proteins that use different phosphoryl donors, a multiphosphoryl protein of the phosphoenolpyruvate-dependent carbohydrate:phosphotransferase system in bacteria, ATP in animals, plants, and some bacteria. The Dha kinase of Escherichia coli consists of three subunits, DhaK…
The dihedral angle between the two porphyrins in meso–meso-linked ZnII diporphyrin can be modulated effectively by adding 1,7-diaminoheptane, which coordinates at the both ZnII centers (see picture). This mechanical torsion gives rise to a decrease in the energy of the S1 state in the meso–meso-linked ZnII-diporphyrin…
Gold-Nanopartikel mit enger Größenverteilung wurden durch oberflächeninitiierte lebende Radikalpolymerisation mit wohldefinierten Polymerbürsten beschichtet. Die Goldteilchen bilden hochgeordnete zweidimensionale Strukturen (siehe Bild), und die Abstände zwischen den einzelnen Teilchen können gut kontrolliert werden.