Materials Literature
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Characteristic photostimulated luminescence (fluorescence) in the visible range is reported from theta transition alumina prepared by using a variety of methods. The luminescence is associated with trace concentrations of chromium and can be intensified by intentional chromium doping. The luminescence from theta‐alumi…
Abstract Gas phase selective oxidation of propylene to propylene oxide (PO) or propionaldehyde (PA) in the presence of H2 and O2has been carried out with a propylene conversion in the range of 0.5-3.7% over gold deposited on titanosilicates by deposition-precipitation (DP) method; PO was obtained with a selectivity ab…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTSubstrate Binding to the α-Ketoglutarate-Dependent Non-Heme Iron Enzyme Clavaminate Synthase 2: Coupling Mechanism of Oxidative Decarboxylation and HydroxylationJing Zhou, Michele Gunsior, Brian O. Bachmann, Craig A. Townsend, and Edward I. SolomonView Author Informati…
We present a detailed study of the activated resistivity of ${\mathrm{La}}_{0.67}{\mathrm{Ca}}_{0.33}{\mathrm{MnO}}_{3}$ films up to 600 K under the influence of high magnetic fields. Data in zero field can be explained by small polaron hopping as treated in the Friedman-Holstein theory. Based on the spin orientation…
The synthesis of dendrimers including P N−P S linkages specifically placed at some generations within the dendrimeric architecture allows the grafting of several types of functional groups at site- and depth-specific locations in the internal layers. The synthesis is carried out up to the fourth generation starting fr…
Continuous highly-ordered mesostructured lamellar-phase thin films are formed by a rapid dip-coating method. The films are made by a dip-coating process from a sol consisting of tetraethoxysilane and the surfactant sodium dodecyl sulfate (SDS). XRD patterns give sharp peaks extending to 14 orders, indicative of a high…
We have studied the molecular mobility of the water and carbohydrate protons in maltose samples as a function of water content and temperature using 1 H NMR. In the NMR signal, slow decaying and fast decaying fractions of protons are distinguished as arising from mobile and immobile (τ c > 3 μs) protons, respectively.…
Electronic and magnetic properties of the perovskitelike compounds of $({\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Dy}}_{x}{)}_{0.7}{\mathrm{Ca}}_{0.3}{\mathrm{MnO}}_{3} (0<~x<~0.5)$ have been studied by measuring electrical resistivity, magnetic susceptibility, magnetization, and magnetoresistance. All the compou…
Measurements of both components of the complex ac conductivity ${\ensuremath{\sigma}}_{m}^{*}(\ensuremath{\varphi},\ensuremath{\omega})$ on continuum percolation systems, based on graphite and boron nitride (G-BN), between 30 Hz and 100 MHz are reported. The results for the real part of ${\ensuremath{\sigma}}_{m}^{*}(…
One-dimensional (1D) structures with nanometer diameter are expected to have remarkable properties that are in principle tunable by varying the diameter and chirality. Most previous research on 1D materials concentrated on carbon-based nanomaterials and require extreme preparation conditions. Here the authors report a…
The molecular adsorption of some probe molecules (CO, H 2 O, and H 2 S) on a 5-fold-coordinated Ti Lewis acid site of the TiO 2 rutile (110) surface is studied within the density functional theory. The substrate is modeled with a small Ti 7 O 9 cluster terminated with pseudo-hydrogens. This is found to describe the el…
A sensitive technique for detecting interstitial ${\mathrm{O}}_{2}$ molecules in ${\mathrm{SiO}}_{2}$ is demonstrated by measuring their infrared $\stackrel{\ensuremath{\rightarrow}}{a}X$ luminescence at 1272.2 nm under a Ti-sapphire laser excitation into the ${\mathrm{O}}_{2}\stackrel{\ensuremath{\rightarrow}}{X}b$ a…
Self-assembly of block copolymers with incompatible segments is known to generate a variety of different morphologies, and provides an attractive, alternative route to nanostructures. The authors describe some of their recent collaborative work on novel organometallic nanostructures made possible by the recent synthet…
The dilatational rheology of the poly(vinylacetate) monolayer onto an aqueous subphase with $p\mathrm{H}=2.0$ has been studied between 1 \ifmmode^\circ\else\textdegree\fi{}C and 25 \ifmmode^\circ\else\textdegree\fi{}C. The combination of several techniques, relaxation after a step compression, oscillatory barrier expe…
Treatment of the silanol ( c -C 5 H 9 ) 7 Si 8 O 12 (OH) with Cp‘‘Ti(CH 2 Ph) 3 (Cp‘‘ = 1,3-C 5 H 3 (SiMe 3 ) 2 ) or TiCl 4 selectively affords the mono(silsesquioxane) complexes Cp‘‘[( c -C 5 H 9 ) 7 Si 8 O 13 ]Ti(CH 2 Ph) 2 ( 1 ) and [( c -C 5 H 9 ) 7 Si 8 O 13 ]TiCl 3 ( 2 ), respectively, while with M(CH 2 Ph) 4 (M…
Light-induced color change of cholesteric copolymers containing a menthone derivative is reported here. In addition, solutions of these copolymers in low molecular mass liquid crystal mixtures to allow local changes of the reflection color are investigated. The ability to reflect visible light makes cholesteric liquid…
The power of genetic engineering methods, along with increasing genomic information, makes heterologous expression of proteins an extremely important biochemical tool. Unfortunately, proteins obtained in this way often are not in their native form, and folding becomes a crucial step in protein production. We have rece…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTA Convergent Route to Novel Aliphatic Polyether DendrimersManikandan Jayaraman and Jean M. J. FréchetView Author Information Department of Chemistry, University of California Berkeley, California 94720-1460 Cite this: J. Am. Chem. Soc. 1998, 120, 49, 12996–12997Publica…
The title compound has been synthesized by slow diffusion of aqueous solutions containing K 4 [Mo(CN) 7 ]·2H 2 O and [Mn(H 2 O) 6 ](NO 3 ) 2, respectively. The compound crystallizes in the monoclinic system, space group P 2 1 / c . The Mo site is surrounded by seven −C−N−Mn linkages in a distorted pentagonal bipyramid…
Abstract Crystal structure is the arrangement of atoms or molecules in the solid state that involves consideration of defects, or abnormalities, in idealized atomic/molecular arrangements. The three-dimensional aggregation of unit cells in the crystal forms a space lattice or Bravais lattice. This article provides a b…