Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
Alumina mesophases have been synthesized by reacting aluminum alkoxides and carboxylic acids with controlled amounts of water in low-molecular-weight alcoholic solvents. Calcination of these materials yields aluminas that are thermally stable to 1073 K and contain randomly ordered pores. Specific surface areas as high…
To determine if high-dose gadolinium chelates are less nephrotoxic than iodinated contrast. Records of 342 patients who had received high-dose gadolinium (.2 to .4 mmol/kg) for magnetic resonance imaging were reviewed to identify patients who had also received iodinated contrast for radiographic examinations. Their cl…
Sequential addition of anionic and cationic polyelectrolytes may lead to the formation of multilayers at a solid surface. The buildup of such multilayers is characterized by a stepwise increase of the adsorbed amount and layer thickness and by alternating highly positive and highly negative values for the ζ-potential.…
Alternating current (ac) magnetic susceptibility data are presented for six distorted cubane complexes of the composition [Mn IV Mn III 3 O 3 X]. Each of these complexes has a well isolated S = 9 / 2 ground state. There is zero-field splitting (ZFS) in the ground states where D, the axial ZFS parameter, is found to be…
Electronic and chemical passivation of CdSe nanocrystals (quantum dots) has been achieved with a thin ZnSe overlayer grown in solution from trioctylphosphine selenide and diethylzinc. Layered particles with a [ZnSe/CdSe] ratio ranging from 0 to ∼5.0 were prepared and characterized by optical absorption spectroscopy, p…
The structure, dynamics, and thermodynamics of gold nanocrystallites passivated by alkylthiolate monolayers were investigated, using molecular dynamics simulations, in different environments as isolated gas-phase clusters, when adsorbed on a graphite surface, and when assembled into three-dimensional superlattices. Th…
A template carbonization technique was applied to prepare carbon nanotubes and submicron-tubes in one dimensional channels. An anodic aluminum oxide film that has uniform and straight channels with a diameter at the nanometer level was used as a one-dimensional template. The pyrolytic carbon deposition on the channel…
Very stable organically modified MCMs are prepared by a simple one-step procedure from readily available starting materials.
The reaction between the [Mn(BS)(H 2 O)] + monomeric and [Mn 2 (μ-BS) 2 (H 2 O) 2 ] 2+ dimeric cations and [Fe(CN) 6 ] 3 - gave rise to cation−anion interaction via the formation of [Fe C⋮N Mn] bridges. Depending on the nature of the Schiff base and regardless of the stoichiometry used, either the trimeric anion [{Mn(…
Films of copper(I) oxide can be electrodeposited by reduction of copper(II) lactate in alkaline solution. Rietveld analysis of electrochemically grown films reveals pure copper(I) oxide with no copper(II) oxide or copper metal present in the films and a lattice parameter of a = 0.4266 nm. The cathodic deposition curre…
Strategies for the preparation of zeolite molecular sieve membranes and layers on different substrates are reviewed. Membranes (and continuous thin films) have been synthesized with ZSM-5 (MFI) type molecular sieves and other zeolites, either as free-standing specimens, grown on various supports according to several s…
Covalent attachment of nanometer-scale colloidal Au particles to organosilane-coated substrates is a flexible and general approach to formation of macroscopic Au surfaces that have well-defined nanostructure. Variations in substrate (glass, metal, Al 2 O 3 ), geometry (planar, cylindrical), functional group (−SH, −P(C…
The crystal chemistry of hydrotalcite-like compounds is investigated by powder diffraction methods such as Rietveld structure refinement, radial distribution function analysis, atom-specific radial distribution analysis obtained from anomalous diffraction data, and EXAFS spectroscopy. The topology of the brucite-type…
Poly(methyl methacrylate) (PMMA) was melt mixed 30:70 into polystyrene (PS) with and without symmetric P(S- b -MMA) diblock copolymers. The molecular weight of the components was varied. After 5 min of shear mixing, the PMMA was dispersed into roughly spherical, submicron particles. Particle size was measured by light…
ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication to the EditorNEXTScattering Form Factor of Block Copolymer MicellesJan Skov Pedersen and Michael C. GerstenbergView Author Information Department of Solid State Physics, Risø National Laboratory, DK-4000 Roskilde, DenmarkCite this: Macromolecules 19…
A disordered mesoporous silica material has been prepared using polymerization of silicate anions surrounding surfactant micelles in the presence of organic salts. The local structure of the material has been investigated using a transmission electron micrograph image of platinum wire grown inside the mesopores. This…
Twelve superparamagnetic Magnetite-Dextran (MD) nanoparticles potentially useful as contrast agents for Magnetic Resonance Imaging (MRI), with different sizes, charges and surface natures, were produced and internally labelled with (59)Fe in order to investigate the effect of their physicochemical properties on their…
Temperature-programmed desorption (TPD) and oxygen isotopic labeling studies were used to probe the dissociation of water on the (100) and (110) surfaces of TiO 2 (rutile). Water TPD spectra from these two surfaces were distinctive. Three monolayer desorption states were observed for the (100) surface (at 205, 250, an…
ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication to the EditorNEXTSynthesis of Branched and Hyperbranched PolystyrenesScott G. Gaynor, Shane Edelman, and Krzysztof MatyjaszewskiView Author Information Department of Chemistry, Carnegie Mellon University, Mellon Institute, 4400 Fifth Avenue, Pittsbu…
A series of amorphous azobenzene-containing polymers were cast as thin films and shown to produce both reversible volume diffraction gratings and high-efficiency surface gratings by laser irradiation at an absorbing wavelength. The latter process involves localized mass transport of the polymer chains to a high degree…