Materials Literature
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The Raman spectra of Sandia Octahedral Molecular Sieves Na 2 Nb 2 - x M x O 6 - x (OH) x •H 2 O (M = Ti, Hf; x ≤ 0.2) (SOMS−Ti and SOMS−Hf) and their parent compound Na 2 Nb 2 O 6 •H 2 O (SOMS) were measured between 24 °C and 600 °C. The spectra of all three materials as well their variations with temperature are almo…
Treating the relaxation dynamics of an ensemble of random hyperbranched macromolecules in dilute solution represents a challenge even in the framework of Rouse-type approaches, which focus on generalized Gaussian structures (GGSs). The problem is that one has to average over a large class of realizations of molecular…
In this work, we report the results obtained during the condensation of various benzaldehydes with ethyl acetoacetate and urea or thiourea, in the presence of a bentonitic clay as catalyst. These reactions were performed under solventless conditions with infrared radiation as the energy source. Both Biginelli and Hant…
Abstract The influence of lignin (L) on the thermal properties and kinetics of crystallization of isotactic polypropylene (PP) is reported in this article. PP blends containing 5 and 15 wt % of L were prepared by mixing the components in a screw mixer. An increase of the thermal degradation temperature of the blends w…
Abstract In Y 2 SiO 5 :Pr 3+ crystals (0.1 at%, 0.3 at%, 0.6 at% , and 1.8 at% Pr 3+ ) characterized by the existence of two types of Pr 3+ optical centers, the energy transfer has been investigated using time‐resolved site‐selective spectroscopy techniques. The results obtained show that at certain conditions there a…
Supercritical fluid decomposition of copper precursors in the presence of hexagonal mesoporous silica matrices are used to prepare ordered copper metal nanowire and nanotube arrays. Evidence is presented which shows that the pore-filling process is accompanied by large expansions of the pore-to-pore distance induced b…
Abstract Solubility and diffusion data are presented for methane and carbon dioxide gases in high‐density polyethylene. The polymer was cut from extruded piping intended for use in offshore oil and gas applications. The measurements were carried out with a high‐pressure microbalance. The properties were determined fro…
Crowning Glory: Twelve μ2-sulfur donors are located above and below an Ni6 ring to form a double crown cluster (see picture). This [12]metallacrown-6 nickel(II) cluster was synthesized by spontaneous self-assembly from 2-sulfanylethanol, carbon bisulfide, NaOH, and NiSO4. The hydroxy groups of 2-sulfanylethanol form s…
Composite organosilicon/porogen thin films were deposited via pulsed-plasma chemical vapor deposition. The organosilicon monomer was polymerized using water as the oxidant, allowing incorporation of silanol (Si–OH) moieties for subsequent condensation reactions and crosslinking for enhanced mechanical properties. The…
Facile generation of naked-metal particles by stripping the ligands from transition-metal–carbonyl clusters for gas-phase studies by FTICR–MS is achieved by using ESI combined with collision induced dissociation (see picture).
The multilayers of poly(amido amine) dendrimer (fourth generation amine-terminated, G4NH 2 ) and conducting sulfonated polyaniline (SPANI) were successfully deposited onto solid substrates by alternatively dipping in SPANI and G4NH 2 solutions. Multilayer growth was monitored by ultraviolet−visible absorption spectros…
The structure of the catabolic alanine racemase, DadX, from the pathogenic bacterium Pseudomonas aeruginosa, reported here at 1.45 A resolution, is a dimer in which each monomer is comprised of two domains, an eight-stranded alpha/beta barrel containing the PLP cofactor and a second domain primarily composed of beta-s…
A dual direct current and radio frequency (DC-RF) plasma system was used to deposit hydrogenated diamond-like carbon (DLC) films from methane plasma. It has the advantages of separately controlling ion density and ion energy by RF power and DC bias, respectively, over conventional simply capacitive-coupled radio frequ…
We present a streamlined limiting case of the theory of Oritz & Repetto for crystals with microstructure in which the crystals are assumed to exhibit infinitely strong latent hardening. We take this property to signify that the crystal must necessarily deform in single slip at all material points. This requirement int…
The aim of this study was to show that multilayer fractal Brunauer−Emmett−Teller (mfBET) theory can be used as a tool to obtain information about the distribution of water in cellulose powder particles of varying crystallinity. Microcrystalline cellulose, agglomerated micronized cellulose, low-crystallinity cellulose,…
We analyze the temporal fluctuations of the flow field associated with a shear-induced transition in a lyotropic lamellar phase: the layering transition of the onion texture. In the first part of this work [Salmon et al., Phys. Rev. E 68, 051503 (2003)], we have evidenced banded flows at the onset of this shear-induce…
Porphyrin macrocycles composed of five and six units of m-gable imidazolylporphyrinatozinc (1-Zn) were synthesized by self-assembled cyclization followed by ring-closing metathesis linkings. Each porphyrin macrocycle was isolated by GPC chromatography, and their molecular weights were determined by MALDI-TOF mass spec…
Strong photoluminescence bands range from 300 to 600 nm at room temperature have been observed in anodic alumina membranes (AAM). It was found that the photoluminescence (PL) intensity and peak position of AAM depend strongly on the excitation wavelength, and the PL intensity of AAM prepared in C 2 H 2 O 4 is much hig…
We use a density-functional based tight-binding method to study diamond growth by ${\mathrm{C}}_{2}$ on a nonhydrogenated diamond $(100)\ensuremath{-}(2\ifmmode\times\else\texttimes\fi{}1)$ surface. The study is motivated by advances in the growth of ultrananocrystalline diamond (UNCD) films under hydrogen-poor condit…
Photoinduced effect in a ferromagnetic perovskite ${\mathrm{La}}_{0.6}{\mathrm{Sr}}_{0.4}{\mathrm{MnO}}_{3}$ was investigated by femtosecond pump-probe spectroscopy. By utilizing magneto-optical Kerr rotation as a probe, the photoinduced dynamics of the spins was observed independently of the quasiparticle relaxation…