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。
A photoluminescent porous silicon microcavity is exposed to saturated vapor of ethanol. The ethanol substitutes the air inside the pores giving rise to a progressive monotonic redshift of the interference pattern of the photoluminescence spectrum. On the other hand, the photoluminescence intensity of the cavity peak o…
The electronic structure of a single pentagon in a hexagonal carbon lattice has been revealed on an atomic scale by scanning tunneling microscopy. The pentagon is located at the apex of the conical protuberance of the graphitic particle. The enhanced charge density localized at each carbon atom in the pentagon is iden…
The electronic and optical properties of the new cubic spinel nitrides $c\ensuremath{-}{\mathrm{Si}}_{3}{\mathrm{N}}_{4},$ $c\ensuremath{-}{\mathrm{Ge}}_{3}{\mathrm{N}}_{4},$ and that of the predicted double nitrides $c\ensuremath{-}{\mathrm{SiGe}}_{2}{\mathrm{N}}_{4}$ and $c\ensuremath{-}{\mathrm{GeSi}}_{2}{\mathrm{N…
Ultrabright ultrasmall (∼1 nm) blue luminescent Si29 nanoparticles are chlorinated by reaction with Cl2 gas. A Si–N linkage is formed by the reaction of the chlorinated particles with the functional amine group in butylamine. Fourier transform infrared spectroscopy and x-ray photospectroscopy measurements confirm the…
We study theoretically the spin dynamics of antiferromagnetic molecular rings, such as the ferric wheel Fe10. For a single nuclear or impurity spin coupled to one of the electron spins of the ring, we calculate nuclear and electronic spin correlation functions and show that nuclear magnetic resonance (NMR) and electro…
Monocrystalline ZnO columns grown in electrodeposition were converted to ZnS using ion exchange reactions in H2S or S vapor. At ∼400 °C the reaction with H2S only affects a thin layer of 10–30 nm thickness at the surface of the ZnO crystallites, and ZnS-coated ZnO columns are produced. Exploiting the large difference…
The electromigration threshold in copper interconnects is reported in this study. The length-dependent electromigration degradation rate is observed and quantified in the temperature range of 295–400 °C. Based on the Blech electromigration model [I. A. Blech, J. Appl. Phys. 47, 1203 (1976)], a simplified equation is p…
Colossal magnetoresistive La0.7Sr0.3MnO3 thin films have been grown under tensile strains on (100)-SrTiO3 substrates and compressive strains on (100)-LaAlO3 and (110)-NdGaO3 substrates by pulsed laser deposition. Using magnetic force microscopy (MFM), a “feather-like” magnetic pattern, characteristic of films with an…
In the calculation of partial atomic charges, for use in molecular mechanics or dynamics simulations, it is common practice to select only a single conformation for the molecule of interest. For molecules that contain rotatable bonds, it is preferable to compute the charges from several relevant conformations. We pres…
An oxide thermoelectric device was fabricated using Gd-doped Ca3Co4O9 p-type legs and La-doped CaMnO3 n-type legs on a fin. The power factors of p legs and n legs were 4.8×10−4 Wm−1 K−2 and 2.2×10−4 Wm−1 K−2 at 700 °C in air, respectively. With eight p–n couples the device generated an output power of 63.5 mW under th…
Lanthanide ions have been doped into cobalt spinel ferrites using an oil-in-water micellar method to form CoLn0.12Fe1.88O4 nanoparticles with Ln=Ce, Sm, Eu, Gd, Dy, or Er. Doping with lanthanide ions (LnIII) modulates the magnetic properties of cobalt spinel ferrite nanoparticles. In particular cases of Gd3+ or Dy3+ i…
A molecular beam of manganese clusters, $\mathrm{Mn}{}_{n}$ $(n\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}11--99)$, produced at 68 K is deflected toward high field by a gradient field magnet. These results indicate that $\mathrm{Mn}{}_{n}$ clusters in this size range are superparamagnetic species whose intrins…
This letter describes the monolithic integration of rubber-stamped thin-film organic transistors with polymer-dispersed liquid crystals (PDLCs) to create a multipixel, flexible display with plastic substrates. We report the electro-optic switching behavior of the PDLCs as driven by the organic transistors, and we show…
Single-wall carbon nanotubes (SWCNTs) were highly aligned by an external electric field. The results suggest that the alignment of SWCNTs shows significant dependencies on the frequency and the magnitude of the applied electric field. The electric field with 5 MHz straightened out the SWCNTs and created highly oriente…
Materials showing reversible resistive switching are attractive for today’s semiconductor technology with its wide interest in nonvolatile random-access memories. In doped SrTiO3 single crystals, we found a dc-current-induced reversible insulator–conductor transition with resistance changes of up to five orders of mag…
Magnetization of the compound LaFe11.4Si1.6 with the cubic NaZn13-type structure was measured as functions of temperature and magnetic field around its Curie temperature TC of ∼208 K. It is found that the magnetic phase transition at TC is completely reversible. Magnetic entropy change ΔS, allowing one to estimate the…
The combination of high sensitive superconducting quantum interference device (SQUID) with high quality nanoparticles allowed to check the simplest classical model describing the magnetisation reversal by uniform rotation which were proposed more than 50 years ago by Neel, Stoner and Wohlfarth. The micrometer sized SQ…
Data on the gastrointestinal absorption of 12 elements have been reviewed. In each case, absorption is expressed as the fraction of the ingested element absorbed to blood, referred to as the f1 value, applying to intakes of unspecified chemical form by average population groups. The level of confidence in individual a…
We present a method for the synthesis of CdS and CdS x Se 1 - x nanocrystals by precipitation from a solution of cadmium carboxylate in dimethyl sulfoxide (DMSO) with or without elemental S (Se). The reaction in the presence of hydrazine has also been investigated. The CdS particle size, determined by X-ray diffractio…
A Raman analysis was conducted to examine the disordered structures of poly(lactic acid). Simulated spectra were obtained for an ensemble of chains generated by several rotational isomeric state models. Analysis of the differences between simulated and experimental spectra showed that the rotational isomeric state rep…