Materials Literature
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We demonstrate a magnifying superlens that can be integrated into a conventional far-field optical microscope. Our design is based on a multilayer photonic metamaterial consisting of alternating layers of positive and negative refractive index, as originally proposed by Narimanov and Engheta. We achieved a resolution…
The diffraction limit of light, which is causd by the loss of evanescent waves in the far field that carry high spatial frequency information, limits the resolution of optical lenses to the order of the wavelength of light. We report experimental demonstration of the optical hyperlens for sub-diffraction-limited imagi…
Structural proteomics is an emerging scientific field aiming to obtain one or more representative 3D structures for every structural domain family in nature by application of high throughput structure determination techniques. These structures, and the corresponding protein production vectors and resonance assignments…
The low-temperature heat capacity of perovskite-type PrGaO 3 has been measured in the temperature range from 2 to 320 K. Thermodynamic standard values at 298.15 K are reported. An initial Debye temperature θ D (0) = (480 ± 10) K was determined by fitting the calculated lattice heat capacity. The entropy of the derived…
Abstract We calculated and analyzed the effects of temperature and crystallite size on the Raman properties of nanocrystalline anatase TiO 2 by using the related models mentioned previously [Tang and Herman, Phys. Rev. B 43 , 2299 (1991); Richter et al., Solid State Commun. 39 , 625 (1981)]. The temperature dependence…
Mesoporous SiO2-P2O5 films were synthesized from the vapor phase onto a silicon substrate. First, a precursor solution of cetyltrimethylammonium bromide (C16TAB), H3PO4, ethanol, and water was deposited on a silicon substrate by a spin-coating method. Then, the C16TAB-H3PO4 composite film was treated with tetraethoxys…
As part of a programme to study structural phase transitions in strontium tellurite, SrTeO3, (STO), the structure of the β-form has been determined at 473 K using single-crystal analysis. Both the structural and non-linear optical measurements indicate an α–β first-order phase-transition temperature that is close to 3…
Three Surirella taxa described by O.Muller from material collected at the beginning of the 20(th) century in Lakes Malawi and Malombe were re-evaluated, and lectotypes are assigned from the original material. One infraspecific taxon, S. nyassae var. sagitta, was synonymized with the nominate variety of S. nyassae and…
We report a study of the ultrafast single particle dynamics in quasi-one-dimensional ${\mathrm{NbSe}}_{3}$ whisker crystals using a two-color pump-probe measurement. A selective enhancement of the relaxation dynamics connected with one of the two charge-density-wave (CDW) phases was realized by tuning the probe energy…
Select members of a series of structurally characterized calcium aryloxides (Ca(OAr) 2 ) were found to influence the morphologies and phases of the final calcium ceramic nanomaterials produced, independent of the process route investigated. The Ca(OAr) 2 were synthesized using an amide alcohol exchange route between […
Gallium-doped boehmite nanostructures with varying Ga content have been prepared at low temperatures via a soft-chemistry route in the presence of poly(ethylene oxide) (PEO) surfactant. The effect of Ga content, hydrothermal temperature, and mixing procedures on the growth of boehmite nanostructures was systematically…
The use of hydrofluoroether liquid wetted wipes for the decontamination of sensitive equipment is attracting great interest. Contacting the contaminated equipment with such wipes results in the rapid removal of surface contaminants. Because adsorption from the liquid phase involves larger molecules than those found in…
The dinuclear complex [[Tl(eta6-toluene)][Au(C6Cl5)2]] (1) displays very intense blue phosphorescence and a rigidochromic behavior in the solid state. The photophysical measurements in a glassy solution display an oligomerization process via metal-metal interactions. Density functional theory calculations show a disto…
Two symmetric triblock polystyrene−butadiene−polystyrene (SBS) copolymers with different initial morphologies were grafted with varying amounts of isobutyl-substituted polyhedral oligomeric silsesquioxane (POSS) molecules. The POSS octamers, R‘R 7 Si 8 O 12, were designed to contain a single silane functional group, R…
Abstract Manganese and copper doped ZnO films and nanowire arrays were prepared by cathodic electrodeposition from aqueous solution. The electrochemical process was examined by linear voltammetry and the morphology and the composition of obtained semiconductor were observed by SEM and EDX measurements. Optical absorpt…
Ag/NiO composite nanofibers have been synthesized and assembled by electrospinning. The prepared nanofibers have a high electrical conductivity of 0.5 × 105 S/cm. Because of its high conductivity and simple synthetic method, electrospun Ag/NiO nanofiber can be potentially used as interconnects for future nanoelectroni…
Fluorescent dyes rhodamine 6G (R6G) and rhodamine B (RhB) were simultaneously introduced to mesoporous MCM-41, SBA-15, and MCM-48 molecular sieves. XRD, N 2 adsorption−desorption isotherm, atomic absorption analysis, and fluorescence emission and lifetime were employed to investigate these composite systems. Photolumi…
A gradient-driven methodology has been developed to manipulate the movement of dendritic macromolecules. Poly(propyleneimine) dendrimers, labeled with rhodamine B, are attached to glass substrates via multiple imine bonds. The dendrimers are able to move on the surface by the hydrolysis and re-formation of these imine…
The structural and magnetic properties of the hexagonal four-layer form of $\mathrm{Sr}\mathrm{Mn}{\mathrm{O}}_{3}$ have been investigated by combining magnetization measurements, electron diffraction, and high-resolution synchrotron x-ray and neutron powder diffraction. Below $350\phantom{\rule{0.3em}{0ex}}\mathrm{K}…
Quantum criticality of metal-insulator transitions in correlated electron systems is shown to belong to an unconventional universality class with violation of the Ginzburg-Landau-Wilson (GLW) scheme formulated for symmetry breaking transitions. This unconventionality arises from an emergent character of the quantum cr…