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。
Numerous experimental indications suggest that the Hume-Rothery mechanism plays an important role in stabilizing quasicrystalline and amorphous phases. However, the exponential damping of the conventional Friedel oscillations at the relevant, elevated temperatures $T$ poses a severe challenge to the HR stabilization.…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTA Novel Octupolar Metal−Organic NLO Material Based on a Chiral 2D Coordination NetworkWenbin Lin, Zhiyong Wang, and Ling MaView Author Information Department of Chemistry, Brandeis University Waltham, Massachusetts 02454 Cite this: J. Am. Chem. Soc. 1999, 121, 48, 1124…
A new methacrylate with a tethered silacyclobutane moiety, 6-(methylcyclotrimethylenesilyl)hexyl methacrylate, has been synthesized. Radical polymerization (thermal) yielded a linear poly(methacrylate) without affecting the silicon-containing four-membered ring. Photoactivated ring-opening polymerization of the silacy…
We have performed a theoretical investigation of the optical properties of the molecule chromone, using multireference perturbation theory (CASPT2) and time-dependent density functional theory (DFT) methods. The structure of the molecule was optimized at the DFT level and at the level of complete active space self-con…
Ab initio molecular orbital calculations have been carried out for silicate, aluminosilicate, and aluminate clusters in order to study the NMR characteristics of oxygen sites that are possibly present in the structure of aluminosilicate glasses and melts. Of particular interest are the different types of bridging oxyg…
Kaolinite hydroxyl surfaces have been modified upon intercalation with cesium acetate under a range of conditions. Upon intercalation of both low- and high-defect kaolinites with cesium acetate at 25 °C, additional infrared hydroxyl stretching bands are observed at 3606 and at 3603 cm - 1 . New infrared hydroxyl defor…
A novel resonant method based on a tunnel-diode oscillator (TDO) is used to study the dynamic transverse susceptibility in a Fe nanoparticle system. The magnetic system consists of an aggregate of nanometer-size core (Au)-shell (Fe) structure, synthesized by reverse micelle methods. Static and dynamic magnetization me…
The magneto-impedance (MI) of glass-coated Fe-Ni-Cu microwires was investigated for longitudinal radio-frequency (RF) currents up to a frequency of 200 MHz using an RF lock-in amplifier method. The MI, defined as DZ/Z = [Z(H)-Z(H=0.3T)]/Z(H=0.3T), displays a peak structure (negative MI) at zero field for RF currents w…
Colloidal dispersions of rod-shaped gold particles are obtained by electrodeposition of gold in the nanopores of anodized alumina attached to a conductive support followed by dissolution of the alumina and release of the rods from the support. Coagulation is prevented by steric repulsion due to adsorption of poly(viny…
A software package has been developed for simulating and designing multipole systems containing electrostatic round lenses, electrostatic and magnetic quadrupole, hexapole and octopole lenses, and Wien filters. Using our SOFEM and 3D packages, the field functions and their derivatives of these optical elements can be…
We present for the first time a theory for the long-time wave number ( k -) dependent collective and self-diffusion coefficients D L ( k ,ϕ) and D S L ( k ,ϕ), respectively, of neutral colloidal suspensions at high volume fractions ϕ. This theory is based on the Smoluchowski equation with mean-field–like hydrodynamic…
A new technique for measuring the twist elastic constant (K22) using an in-plane electrode structure was investigated. The variation in the temperature dependence of K22 with respect to the molecular structure of fluorinated phenylbicyclohexane (PBC) compounds was investigated. The experimental cell has in-plane elect…
Pentasilver iododiphosphate, Ag 5 IP 2 O 7 , is the compound with the lowest AgI content in the pseudo-binary system AgI-Ag 4 P 2 O 7 . The X-ray single-crystal structure determination establishes that the coordination spheres of all the silver ions contain both oxide and iodide anions. Silver-ion conduction pathways…
New thermoplastic nonsegmented thiopolyurethanes were obtained from the low-melting aliphatic–aromatic thiodiols 4,4′-bis(2-hydroxyethylthiomethyl)benzophenone (BHEB), 4,4′-bis(3-hydroxypropylthiomethyl)benzophenone (BHPB), and 4,4′-bis(6-hydroxyhexylthiomethyl)benzenophenone(BHHB) as well as hexamethylene diisocyanat…
An improved method is described for the computation of integrals involving effective core potentials. The improved method provides better scalability to higher angular momenta as well as improved speed. The new method is also applied to the determination of the minimum energy structures of Si8C12, Ge8C12, and Sn8C12,…
A new method is presented for simulating discrete Coulomb interaction effects in electron and ion beam columns. The method is applicable to the latest high-throughput electron and ion beam projection systems currently under development as possible candidates for next generation lithography. Monte Carlo simulation is u…
The transformation of a chemisorbed O layer on the Al(111) surface into Al2O3 under electron impact has been monitored by high-resolution electron energy-loss and x-ray photoelectron spectroscopies. Electron irradiation (100 eV) of chemisorbed O was observed to cause spectroscopic changes in the surface layer indicati…
A significant breakthrough in the nitride chemistry of main group elements has been achieved: Surprisingly Sn(3)N(4), for which there had been no proof of existence until now, as well as the isotypic high-pressure polymorphs gamma-Si(3)N(4) and gamma-Ge(3)N(4) have been synthesized. All three compounds crystallize in…
Yttrium sodium oxalate tetrahydrate, [Y(H 2 O)]Na-(C 2 O 4 ) 2 .3H 2 O, was obtained from hydrothermal synthesis and its structure determined from single-crystal X-ray diffraction data. The structure consists of corrugated layers of ninefold-coordinated Y atoms linked together by oxalate groups. Na atoms and water mol…
High-quality ZnO crystals have been grown by vapor-phase techniques and by the hydrothermal method. Depending on the surface preparation technique, some hydrothermally grown crystals contain strain. These strains result in energy shifts of the free excitons as well as relaxation of the selection rules. The Γ6 unallowe…