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。
We have synthesized two forms of erbium tetracyanoplatinates, Er2[Pt(CN)4]3.21H2O (red form) and Er2[Pt(CN)4]2.SO4.11.5H2O (yellow form), and determined their crystal structures by X-ray diffraction. While the red form crystallizes in the orthorhombic space group Pbcn, with a = 15.4848(3) A, b = 13.8186(2) A, c = 19.0…
We present the results of molecular dynamics simulations of two-dimensional (2D) hard disk systems in the vicinity of melting. The simulations are used to calculate the elastic constants, which can be used to estimate the location of the Kosterlitz-Thouless dislocation unbinding transition. Simulations on defect-free…
The response of Al 2 O 3 and Al 2 O 3 /SiC nanocomposites to lapping and polishing after initial grinding was investigated in terms of changes in surface quality with time for various grit sizes. The surface quality was quantified by surface roughness ( R a ) and by the relative areas of smooth polished surfaces as op…
In this paper we present a modified ‘rotating analyser’ technique that allows rapid and continuous in situ measurements of the optical tilt angle (θ). Using this technique we will detail the tilt angle behaviour in mono-mesogen (AB) and bi-mesogen (ABA) low molar mass orga- nosiloxanes. The AB type molecules exhibit o…
In a recent paper [J. Opt. Soc. Am. A 16, 1108 (1999)] Logofatu et al. demonstrated by experimental and numerical evidence that the 0th-order cross-polarization (s to p and p to s) reflection coefficients of isotropic, symmetrical, surface-relief gratings in conical mount are identical. Here an analytical proof is giv…
Large scale atomistic simulations are used to investigate the properties of screw dislocation dipoles in copper. Spontaneous annihilation is observed for dipole heights less than 1 nm. Equilibrated dipoles of heights larger than 1 nm adopt a skew configuration due to the elastic anisotropy of Cu. The equilibrium split…
The asymptotic theory is used for evaluation of the cross section of resonant charge exchange for most elements of the periodical system. An analysis is given of the accuracy of the data obtained. The error for the cross sections at collision energies of the order of 1 eV varies from 1% for hydrogen and elements of th…
Using half-metallic ferromagnets in spin-dependent devices, like spin valves and ferromagnetic tunnel junctions, is expected to increase the device performance. However, using the half-metallic ferromagnet NiMnSb in such devices led to much less than ideal results. One of the possible sources for this behavior is atom…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTSelf-Assembly of a Polypeptide Multi-Block Copolymer Modeled on Dragline Silk ProteinsYun Qu, Sonha C. Payne, Robert P. Apkarian, and Vincent P. ConticelloView Author Information Department of Chemistry, Oglethorpe University Atlanta, Georgia 30319 Integrated Microscop…
We describe polarizing films formed from the lyotropic liquid crystalline phases of dyes dissolved in water. The dye polarizers possess a high dichroic ratio close to that of conventional polarizers. In addition, the dried dye films provide a uniform homogeneous orientation for thermotropic nematic materials. Therefor…
Environmental conditions under which localized corrosion of carbon steel could take place in simulated groundwater were examined. Using specimens with crevices, it was determined that at potentials above the repassivation potential, the ratio of the chloride concentration to the total carbonate concentration, solution…
The synthesis of aluminum nitride (AlN) via self‐propagating high‐temperature synthesis (SHS) was attempted, using aluminum powder that was mixed with AlN powder as a diluent. The AlN content in the reactant was varied over a range of 30%–70%, and the nitrogen pressure was varied over a range of 0.1–1.0 MPa. The SHS r…
A mathematical model based on Frenkel's theory for charged defect segregation at interfaces is used to calculate the equilibrium grain boundary depletion layer widths and conductivity profiles in acceptor‐doped SrTiO 3 ceramics. The calculations examine the effect of oxygen vacancy equilibration during annealing at mo…
Glasses in the system xFeCl3–10Fe2O3–(90–x)P2O5 have been prepared by the normal quenching method over a wide range of composition (x = 15 up to 50 mol%). The glass structure has been investigated using IR spectral analyses which shows that the intermediate range order is affected by substitution of FeCl3 for P2O5. Th…
We have measured the photoconductivity of insulative SrTiO 3 single crystal whose band-gap is 3.2 eV. We have found that the dependence of resistivity on temperature shows metallic conduction under white light irradiation and the resistivity drops rapidly below 105 K. This temperature at which a giant photoconductivit…
The absolute detection efficiency (ADE) of microchannel plates for neutral sodium and potassium atoms is measured in the low keV energy range. It is shown that ADE is primarily a function of the particle energy. This result is compared to measurements made by other authors for ionic particles.
A new technique for measuring the electro-optic coefficient of nonlinear optical polymer is described. In an attenuated-total-reflection experiment the refractive index of the poled polymer is changed because of the Pockels effect. This change causes a shift of the angular position of the surface plasmon modes that co…
Samples of rapeseed oils were oxidized at isothermal conditions in the cell of a pressure differential scanning calorimeter (PDSC). The experiments were carried out under 1400 kPa oxygen pressure at a temperature in the range of 113—144 °C. From resulting PDSC exotherms the times to reach the peak maximum (τmax) were…
Abstract Methods for the incorporation of phosphate and phosphonate units into the side groups of phosphazenes, at both the high polymeric and cyclic trimer levels, are described and evaluated. Halogenated organophosphates were used as the phosphorylating agents and were allowed to react with hydroxyl‐ or lithio‐funct…
Infrared-to-visible upconversion emission enhancement through thermal effects in Yb3+-sensitized Pr3+-doped fluoroindate glasses excited at 1.064 μm is investigated. A twentyfold increase in the 485 nm blue emission intensity as the sample temperature was varied from 20 to 260 °C was observed. The visible upconversion…