Materials Literature
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Abstract A multiple charge‐transfer second‐order nonlinear optical (NLO) chromophore 2,3‐bis(4‐aminophenyl)‐5,6‐dicyanopyrazine (BAPDCP) was successfully designed and synthesized. It was characterized by 1 H NMR, mass spectrometry, Fourier transform infrared spectroscopy, and elemental analysis. The first hyperpolariz…
Abstract The colourless title compound scandium(III) oxoselenate‐(IV) Sc 2 Se 3 O 9 (≡Sc 2 [SeO 3 ] 3 ) was obtained by reacting a 1:3‐molar mixture of Sc 2 O 3 and SeO 2 at 830°C for seven days in an evacuated torch‐sealed silica vessel as needle‐shaped single crystals. It crystallizes hexagonally (space group: P6 3…
RATIONALE AND OBJECTIVES: To evaluate 4 doses of gadobenate dimeglumine (Gd-BOPTA) for contrast-enhanced magnetic resonance angiography (CE-MRA) of the pelvic arteries and to compare CE-MRA with unenhanced time-of-flight MRA (2D-TOF-MRA). METHODS: A multicenter Phase II dose-finding study was performed in 136 patients…
There has been recent interest in photoinduced chirality in azo polymers upon irradiation with circularly polarized light. The mechanism of ordering is thought to involve successive twisting of the achiral photoactive azo-containing side chains in response to the handedness of the pump polarization. In this study, a t…
We found that mannitol-1-phosphate dehydrogenase (MtlD), a component of the mannitol-specific phosphotransferase system, is required for glucitol assimilation in addition to GutR, GutB, and GutP in Bacillus subtilis. Northern hybridization of total RNA and microarray studies of RNA from cells cultured on glucose, mann…
In situ Raman spectra measurements have been employed to reveal the crystallization process of sol-gel derived Bi 4- x La x Ti 3 O 12 (BLT) thin films. The Raman spectra of BLT films with a La composition x of 0.75 were measured with increasing temperature up to 800°C in air and N 2 ambient. It is demonstrated that Bi…
The objective of this research was to determine whether grain boundary deformation plays a direct role in intergranular stress corrosion cracking (IGSCC) of Ni-16Cr-9Fe in high-temperature water. The difference in deformation and cracking behavior between special grain boundaries, or coincident site lattice boundaries…
A simple, inexpensive, and rapid electrophoresis technique was developed for use as a routine tool for evaluating purity of polyamidoamine (PAMAM) dendrimers. A variety of factors influencing migration of generations 0-7 dendrimers on nongradient polyacrylamide gels were evaluated. The low generation dendrimers were f…
This article deals with different aspects of photo-induced processes in dendrimers, such as site isolation, energy and electron transfer processes, and photo-isomerisation of peripheral groups. By discussing several examples, from our own work, we intend to give some more insight with respect to these topics.
The absolute specific heat capacity of poly(α-methyl styrene) and mixtures with its pentamer were found to be independent of concentration at temperatures from 240 to 480 K. Extrapolation to 100% polymer yielded the equilibrium specific heat capacity for the polymer at temperatures as much as 180 K below the glass tem…
The optical absorption spectrum of the as-grown ${\mathrm{PWO}}_{4}$ crystal mainly exhibits a weak band peaking at 350 nm, overlapping with the absorption edge of the crystal. The ultraviolet-irradiated crystal emits a strong band peaking at 420 nm and a broad band in the range of 500--700 nm almost in pairs along wi…
Two commercially available additive‐containing silicon nitride materials were exposed in four environments which ranged in severity from dry oxygen at 1 atm pressure, and low gas velocity, to an actual turbine engine. Oxidation and volatilization kinetics were monitored at temperatures ranging from 1066° to 1400°C. Th…
Friction between fibers inside yarns is generally important for determining the physical behavior of textiles. The tendency of cellulosic fibers to slide in a yarn directly influences the extent of fuzz formation during abrasive treatment. This paper presents a test method to determine the slipping behavior of fibers…
Doubly doped YVO4:Pb2+, Eu3+ red phosphor materials with fixed Eu3+ concentration (5 mol%) and varying Pb2+ concentration were prepared via a self-propagating (combustion) synthesis. This consisted of bringing a saturated aqueous solution of the desired metal salts and a suitable organic fuel to the boil, until the mi…
The structure of (NH 4 ) 0.5 V 2 O 5 · m H 2 O ( m ≈ 0.9), a representative member of the family of intercalated solids with reduced V 2 O 5 xerogel framework, has been successfully determined using the atomic pair distribution function (PDF) technique. We show that at the atomic scale (NH 4 ) 0.5 V 2 O 5 · m H 2 O is…
Recovery stresses generated by neat shape memory wires under different constraint conditions have been studied in detail. The thermomechanical conditions applied in the experiments were very close to the biasing conditions in polymer composites with embedded shape memory wires. The parameters of the present experiment…
We have succeeded to grow chemical-vapor-deposited diamond films at reasonably high growth rates using high microwave power of 3.8 kW and high methane concentration ratios (CH4/H2) of ≥4.0%. Growth rates of ≥2 μm/h have been attained for (100) homoepitaxial growth by utilizing high-density microwave plasma. These homo…
Isolated single-walled carbon nanotubes (CNTs) were grown by chemical vapor deposition methods on Fe/Mo/Al 2 O 3 catalysts, which were patterned by microcontact printing. The pattern allowed us to trace back and investigate the same isolated CNT by atomic-force (AFM) and confocal Raman microscopy with different excita…
Optical properties of Eu3+ ions in oxyfluoride glasses and glass ceramics doped with two different concentrations, 0.1 and 1 mol %, have been analyzed and compared with previous results for higher concentrated samples, 2.5 mol %. The Eu3+ ions in the 0.1 mol % doped glass ceramics are diluted into like crystalline env…
The fluctuation-dissipation relation (FDR) is measured on the dielectric properties of a polymer glass (polycarbonate) in the range 20 mHz–100 Hz. It is found that after a quench below the glass transition temperature, the fluctuation-dissipation theorem is strongly violated. The amplitude and the persistence time of…