Materials Literature
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The simulation study on Frenkel pair creation in vanadium by L.A. Zepeda-Ruiz et al. (Phys. Rev. B 67, 134114, 2003) is criticized for its lack of reference to existing experimental work and for generally inadequate treatment of literature data. Hence, the validity of the ensuing discussion of various results (e.g. th…
From a multiple scale analysis, we find an analytic solution of spherical and cylindrical Poisson-Boltzmann theory for both a 1:2 (monovalent co-ions, divalent counter-ions) and a 2:1 (reversed situation) electrolyte. Our approach consists in an expansion in powers of rescaled curvature $1/(κa)$, where $a$ is the coll…
We report here the first synthesis of pure boron single-wall nanotubes by reaction of BCl 3 with H 2 over an Mg−MCM-41 catalyst with parallel, uniform diameter (36 ± 1 Å) cylindrical pores. The composition of the tubular structures observed in TEM was confirmed by electron energy loss spectroscopy, and the tubular geo…
Isotopic tracer and kinetic studies are used to probe the identity and reversibility of elementary steps required for H 2 O and CO 2 reforming of CH 4 on supported Pt clusters and to demonstrate a rigorous kinetic and mechanistic equivalence for CO 2 and H 2 O reforming, CH 4 decomposition, and water-gas shift reactio…
The flowerlike ZnO nanostructures, which consisted of swordlike ZnO nanorods, have been prepared by a cetyltrimethylammonium bromide (CTAB)-assisted hydrothermal process at low temperature (120 °C). The XRD pattern indicated that the flowerlike ZnO nanostructures were hexagonal. Furthermore, the SAED and HRTEM reveale…
A new circular position sensor based on giant magnetoresistances has been developed. The sensing film is an AgCo nanogranular thin film patterned in a circular Wheatstone bridge configuration. This alloy shows a high magnetoresistance (8%) at room temperature within the field generated by an NdFeB permanent magnet tha…
Multilayers of alternately adsorbing poly(allylamine) (PAH) and poly(acrylic acid) (PAA) of opposite charges on silica have been studied by the spin labeling technique, as a function of pH. The two polyelectrolytes have been labeled independently by a nitroxide free radical. Its electron paramagnetic resonance spectru…
A new carbon-13 NMR method is presented for the quantitative determination of monomer sequence distributions and average sequence lengths in propylene−1-butene copolymers. Complete carbon-13 NMR chemical shift assignment was finalized: the peaks corresponding to comonomeric sequence distributions are assigned in terms…
The local and intermediate structure of a simulated metal−metalloid glass-forming alloy is reported. The model, due to Kob and Andersen, has been the subject of considerable study in the context of the glass transition. In the A 75 B 25 mixture the low-temperature coordination polyhedra about the B (“metalloid”) parti…
We investigate, using small-angle neutron scattering (SANS), the polymer concentration fluctuations in a particular type of end-linked polystyrene gels, in the swollen state. These gels are obtained from the cross-linking of well-defined end-capped low-polydispersity chains end-linked through a trifunctional cross-lin…
Silica monoliths with ordered arrays of micrometer-scale columns were fabricated from polyacrylamide gel templates. The preparation of the template involves the charged comonomer, N-acryloyl glycine, and is controlled by an externally applied electric field. This approach gives rise to the self-organization of columna…
Abstract The thermal degradation and flame retardancy of poly(butylene terephthalate) (PBT) were studied with a focus on the effect of phosphorous compounds. Thermogravimetric analysis, pyrolysis/gas chromatography/mass spectrometry (Py/GC/MS), and elemental analysis were used to analyze the flame retardancy, which we…
Aerogels with the nominal composition ZrW 2 O 8 have been prepared by pore solvent exchange with liquid CO 2 followed by supercritical drying. These aerogels are amorphous and can be tailored to have extremely high surface areas. Thermal expansion is measured for the amorphous aerogel as well as the aerogel post therm…
Rohr oder Röhrchen? Entgegen früheren theoretischen Untersuchungen ergaben Dichtefunktionalrechnungen (B3LYP/6-31G*) an unterschiedlichen Nanoröhrenmodellen, dass SWCNTs mit O-, NH-, CH2- und SiH2-Addenden offene Strukturen gegenüber Dreiringen bevorzugen. Ferner sind in (8,0)-Zickzack-Nanoröhren die diagonalen C-C-Bi…
The effects of intermolecular interaction on dipole moment (μ), the mean (α) and anisotropy (Δα) of the polarizability, and the first and second hyperpolarizabilities (β and γ, respectively) for four hydrogen bond dimers between two π-systems (HCN···HCN, HNC···HCN, HCN···HNC, and HNC···HNC) have been calculated in the…
The crystallization of calcite in the form of spheroaggregates in aqueous foam stabilized by the surfactant sodium bis-2-ethylhexyl-sulfosuccinate (aerosol OT, AOT) by a method of ion entrapment is described. Reaction of Na 2 CO 3 with Ca 2+ ions electrostatically entrapped in the foam results in the formation of flat…
Material probe analysis for plasma facing surface in the Large Helical Device, T. Hino, A. Sagara, Y. Nobuta, N. Inoue, Y. Hirohata, Y. Yamauchi, S. Masuzaki, N. Noda, H. Suzuki, A. Komori, N. Ohyabu, O. Motojima, LHD Experimental Group
Abstract Two new ketone‐type derivatives were synthesized by the dehydrodecarboxylation of levopimaric acid acrylic acid adduct and of levopimaric acid maleic anhydride adduct in the presence of sulfonic catalysts. The two compounds were also synthesized by coupling of acrylic acid or maleic anhydride with dipimaryl k…
Abstract A salicylic acid–guanadine–formaldehyde (SGF) tercopolymer was synthesized by the condensation of salicylic acid with guanidine carbonate and formaldehyde in 1 : 1 : 2 molar proportions in the presence of 2 M HCl as a catalyst. The SGF tercopolymer was characterized on the basis of elemental analysis and ultr…
The layered cerium iodates Ce 2 (IO 3 ) 6 (OH x ) [ x ≈ 0 ( 1 ) and 0.44 ( 2 )] have been prepared from the reaction of (NH 4 ) 2 Ce(NO 3 ) 6 with I 2 O 5 at 180 °C in aqueous media. The structure of these compounds consists of square antiprismatic Ce centers that are bound by bridging iodate anions and one bridging o…