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。
ADVERTISEMENT RETURN TO ISSUEPREVNoteNEXTThree-Step Synthesis and Absorption and Emission Properties of Peripherally Peralkynylated TetrapyrazinoporphyrazinesRüdiger Faust and Christian WeberView Author Information Christopher Ingold Laboratories, Department of Chemistry, University College London, 20 Gordon Street, L…
A quantitative structure−property relationship (QSPR) investigation was performed to develop a mathematical link between molecular structure and the clearing temperature of a series of structurally related liquid crystals. Molecular structures were encoded by a series of numerical descriptors encoding information rega…
A new ordered oxygen-deficient perovskite, LaBaMn 2 O 5.5, has been synthesized, using the topotactic deoxygenation of the ordered LaBaMn 2 O 6 perovskite. The crystal structure of this manganite was solved in the space group Ammm ( a = 3.86 Å, b = 8.19 Å, c = 15.47 Å) from neutron powder diffraction data. The [Mn 2 O…
We present Monte Carlo simulations for the size and temperature dependence of the diffusion coefficient of adatom islands on the Cu(100) surface. We show that the scaling exponent for the size dependence is not a constant but a decreasing function of the island size and approaches unity for very large islands. This is…
We study the effect on CPP GMR of changing the order of the layers in a multilayer. Using a tight-binding simple cubic two band model (s-d), magneto-transport properties are calculated in the zero-temperature, zero-bias limit, within the Landauer-Buttiker formalism. We demonstrate that for layers of different thicknes…
Selection of candidate materials and processes for manufacturing structural members is of great moment in designing surface micromechanics devices. The known arts of obtaining superficial microstructures, as a rule, with the use of a 'sacrificial' layer were based on the employment of polysilicon as a working material…
Several aspects of the heterogeneous actions of aqueous and gaseous HCl on the chemical behavior of 3,4-epoxycyclopentanone (=6-oxabicyclo[3.1.0]hexan-3-one; 1) included in the asymmetric cages of tri-o-thymotide (TOT) clathrates belonging to space groups P3121 are described, showing specific features strikingly at va…
Manganese–molybdenum–diethyldithiocarbamate [MnMoO2(Et2dtc)4(H2O)] {Et2dtc=diethyldithiocarbamate} complex has exhibited reversible photogalvanic behaviour in aqueous dimethylformamide medium when studied in a Honda cell. The photogalvanic behaviour has been further investigated by varying the pH, temperature and phot…
The phase separation kinetics of ultrathin deuterated poly(styrene)/poly(butadiene) polymer blend films spun cast onto striped self-assembled monolayer (SAM) substrates is studied by atomic force microscopy (AFM). Fourier transform analysis of the AFM topographic data at various stages of the film pattern development…
The Co(OESPz) complex crystallizes in space group P 2 1 / n, with a = 10.260(5) Å, b = 22.650(5) Å, c = 16.720(5) Å, β = 91.680(5)°, and Z = 4 and forms, similarly to the isomorphous Mn(OESPz), solid-state extended one-dimensional aggregates where “ruffled” molecular units are held together by extra planar Co···S inte…
Previous experiments from our group [ Macromolecules 1998, 31, 5964] have established that thermal polymerization of 3,5-bis(4-aminophenoxy)benzoic acid (monomer 1 ) gave a hyperbranched aromatic polyamide (polymer 1 ). Here we show that thermal polymerization of methyl 3,5-bis(4-aminophenoxy)benzoate (monomer 2 ), ha…
A novel concept for the synthesis of molecularly thin polyelectrolyte layers covalently attached to planar solid surfaces is introduced. The polymer monolayers are generated directly at the surface by using self-assembled monolayers of an azo initiator and radical chain polymerization in situ. This “grafting from” app…
The prospects for high thermoelectric performance in phosphide skutterudites are investigated based on first principles calculations. We find that stoichiometric CoP_3 differs from the corresponding arsenide and antimonide in that it is metallic. As such the band structure must be modified if high thermopowers are to…
We examine, using molecular dynamics simulation, the structure and thermodynamics of the (100) and (111) disordered face-centered cubic (FCC) crystal/melt interfaces for a binary hard-sphere system. This study is an extension of our previous work, [Phys. Rev. E 54, R5905 (1996)], in which preliminary data for the (100…
We report the first audio frequency dielectric constant measurements of CO and N_2 in their solid phases. We have observed several new features, including (1) strong hysteresis effects above an onset temperature $T_{h} \simeq 42 K$ in the β-phase of pure N_2, (2) absence of the expected short range antiferroelectric d…
A transition-metal oxide NaCo_2O_4 is a layered oxide in which CoO_2 and Na alternately stack along the c axis. Recently we have found that this compound shows unusually large thermopower with low resistivity, which is comparable to those of Bi_2Te_3. The negative transverse magnetoresistance and the strongly temperat…
The inelastic light scattering in a 2-d electron gas is studied theoretically using the Boltzmann equation techniques. Electron-hole excitations produce the Raman spectrum essentially different from the one predicted for the 3-d case. In the clean limit it has the form of a strong non-symmetric resonance due to the sq…
Telechelic oligo- and poly(dimethylsiloxanes) 1 and 2, with two ureidopyrimidone (UPy) functional groups, have been prepared via a hydrosilylation reaction. The compounds have been characterized in solution by 1 H NMR and viscometry and in the solid state by 1 H NMR and 13 C NMR, FTIR, and rheology measurements. The m…
Exposure of photoluminescent porous Si to alkyllithium reagents results in grafting of the alkyl group to the silicon surface by formation of a Si−C bond. The reaction is proposed to proceed by addition of the alkyllithium reagent across a surface Si−Si bond, forming Si−alkyl and Si−Li surface species. The highly reac…
We investigate to what extent the specific heat of amorphous silica can be calculated within the harmonic approximation. For this we use molecular dynamics computer simulations to calculate, for a simple silica model (the BKS potential), the velocity autocorrelation function and hence an effective density of states g…