Materials Literature
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The novel morphology of BN nanotubes with a collapsed structure has been discovered by a metal-catalyzed treatment. The collapse causes the dramatic enlargement of a specific surface area of BN nanotubes and remarkably enhances the hydrogen storage capacity of BN nanotubes.
High solubility of SWNTs and MWNTs in water is obtained by organic functionalisation; derivatisation with N-protected glycine is also easily achieved.
An extension to the Steinmetz equation is proposed, to enable estimation of hysteresis losses in magnetic core materials with nonsinusoidal flux waveforms. The new formulation is shown to avoid anomalies present in previous modified-Steinmetz-equation calculations of loss with nonsinusoidal waveforms. Comparison with…
Gold-based catalysts have been of intense interests in recent years, being regarded as a new generation of catalysts due to their unusually high catalytic performance. For example, CO oxidation on Au/TiO(2) has been found to occur at a temperature as low as 200 K. Despite extensive studies in the field, the microscopi…
A new program has been developed for ab initio crystal structure determination from powder diffraction data (X-ray and neutron). It uses global-optimization algorithms to solve the structure by performing trials in direct space. It is a modular program, capable of using several criteria for evaluating each trial confi…
A kind of amphiphilic polymer, ES-1, is transferred onto solid substrates as so-called “reversed duckweed” polymeric Langmuir−Blodgett (LB) films. Their orientations, structures, and phase-transition behaviors were studied in detail by infrared (IR) transmission and reflection−absorption (RA) spectroscopy. The IR stud…
Crystal and magnetic structures of complex manganese oxides ${\mathrm{Sr}}_{2}{\mathrm{GaMnO}}_{5+\ensuremath{\delta}}$ $(\ensuremath{\delta}\ensuremath{\simeq}0.01,0.52)$ and ${\mathrm{Ca}}_{2}{\mathrm{GaMnO}}_{5+\ensuremath{\delta}}$ $(\ensuremath{\delta}\ensuremath{\simeq}0.05)$ were studied by neutron powder diffr…
Abstract The effect of siloxane chain length on surface segregation of poly(methyl methacrylate)‐grafted poly(dimethyl siloxane) (PMMA‐ g ‐PDMS)/poly(2‐ethylhexyl acrylate‐ co ‐acrylic acid‐ co ‐vinyl acetate) [P(2EHA‐AA‐VAc)] blends was investigated. The blends of PMMA‐ g ‐PDMS with P(2EHA‐AA‐VAc) showed surface segr…
Abstract Polyurethane prepolymers prepared from toluene 2,4‐diisocyanate, toluene 2,6‐diisocyanate, and polypropylene glycol with a ratio between the isocyanate and hydroxyl groups equal to 2 were analyzed by 1 H nuclear magnetic resonance (NMR) spectroscopy in acetone‐d 6 . Different temperatures and concentrations w…
Changes upon oxidization of carbon nanotubes (CNTs) in structure and Raman spectra are investigated using geometry optimizations and frequency calculations with density functional theory and ONIOM(MO:MO) methods. Macrocycles consisting of six and 12 fused C 6 hexagon units, C 24 H 12 and C 48 H 24 or [6]- and [12]-cyc…
Abstract Poly( L ‐lactide), that is, poly( L ‐lactic acid) (PLLA), poly(ε‐caprolactone) (PCL), and their blend (50/50) films containing different amounts of poly( L ‐lactide‐ co ‐ε‐caprolactone) (PLLA‐CL), were prepared by solution casting. The effects of added PLLA‐CL on the enzymatic hydrolysis of the films were inv…
Water-processable molecular complexes between dextran sulfate (DSA) and polyaniline derivatives (PANIs) have been synthesized by chemical polymerization of corresponding achiral monomer in the presence of DSA. The formation of the macromolecular complex was proved by the FTIR and UV−vis spectra. Interestingly, chiral…
X-ray crystal structures, solid-state photoluminescence, and Kurtz−Perry powder second harmonic generation (SHG) efficiencies of two novel noncentrosymmetric polymeric adducts of CuI with 4-acetylpyridine, a double-stranded “stair” and a single-stranded “chain”, are reported, the latter being a rare example of a [CuX(…
Epitaxial films of cuprous oxide, Cu 2 O, are electrodeposited from aqueous solution onto single-crystalline Si(001). The epitaxial growth of Cu 2 O onto Si is an unexpected result, because there is a strong driving force for the oxidation of Si to form a native amorphous SiO 2 layer. The Cu 2 O films are single-cryst…
Zinc(II) complexes of antipodal beta-tetrasubstituted meso-tetraphenylporphyrin with trifluoromethyl (Zn(TPP(CF(3))(4)) (1a)), bromine (Zn(TPPBr(4)) (2a)), and methyl groups (Zn(TPP(CH(3))(4)) (3a)) were synthesized in order to examine the steric and the electronic effects of trifluoromethyl groups on the macrocycle.…
An extensive search for stable chemisorbed SO 2 configurations on the Pt(111) surface has been performed using first-principles DFT−GGA calculations. The most energetically stable configurations, η 2 -S b,O a and η 3 -S a,O a,O a at fcc sites, where η 2 and η 3 mean that the number of atoms of the adsorbate coordinate…
Abstract Facile syntheses of hyperbranched polyimides were realized by the polymerization of A 2 + BB ′ 2 monomers, 2,2‐bis(3,4‐dicarboxylphenyl) hexafluoropropane dianhydride (6FDA) + 2,4,6‐triaminopyrimidine (TAP), performed by mixing the monomers together in N ‐methylpyrrolidone at 17% w/v concentrations with molar…
We show that the occurrence of pure photoorientation by photoisomerization of azo dye in polymers is influenced by the polymer molecular structure, as well as by the photoisomerization quantum yields and the cis → trans thermal isomerization rate. These findings are rationalized by the study of the photoorientation of…
An efficient and simple method of modification of "inverted" porphyrin is provided by reactions of 5,10,15,20-tetraaryl-2-aza-21-carbaporphyrinatonickel(II) 2 with dihalogenalkanes under basic conditions. The substituents are bound to the internal carbon or external nitrogen of the inverted pyrrole depending on dihalo…
Abstract Epoxy resins containing both phosphorous and silicon were prepared via the fusion process of reacting a phosphorous diol and a silicon diol with a bisphenol‐A‐type epoxy. With various feeding ratios of the reactants, epoxy resins with different phosphorous and silicon contents were obtained. Through curing th…