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。
Density functional theory (DFT) calculations of the energetics, molecular structures, and spin density profiles of metalloporphyrin pi-cation radicals suggest that the common practice of describing these radicals in terms of a universal A(1u)/A(2u) dichotomy is often not justified, confirming a possibility first fores…
We have measured the steady drainage of foams of various surfactants, varying the size of the parietal plateau borders from 0.24 to 2.4 mm. We report an evolution of the power laws of drainage with the bubble size, which cannot be explained by the most recent developments of the drainage theory. We believe that one re…
Redox polyelectrolyte multilayers have been assembled with use of the layer-by-layer (LBL) deposition technique with cationic poly(allylamine) modified with Os(bpy)(2)ClPyCHO (PAH-Os) and anionic poly(styrene)sulfonate (PSS) or poly(vinyl)sulfonate (PVS). Different behavior has been observed in the formal redox potent…
The kind and degree of crystalline phase orientation for clathrate s-PS films, obtained by solution-casting procedures, and for semicrystalline films, obtained by suitable treatments on these cast films, are analyzed. Clathrate as well as nanoporous form films can present high degrees of uniplanar orientation, corresp…
TDDFT calculations confirm a controversial proposal by DiMagno and co-workers that ruffling distortions, by themselves, do not bring about sizable red shifts in the electronic absorption spectra of "simple" nontransition-metal porphyrins. We now report that the same also holds for saddling distortions. The situation i…
The photoinduced electron transfer in differently linked zinc porphyrin-fullerene dyads and their free-base porphyrin analogues was studied in polar and nonpolar solvents with femto- to nanosecond absorption and emission spectroscopies. A new intermediate state, different from the locally excited (LE) chromophores and…
The oxidation of (tmeda)Pt(II)(CH(3))(2) (1, tmeda = N,N,N',N'-tetramethylethylenediamine) to (tmeda)Pt(IV)(OH)(OCH(3))(CH(3))(2) (3) by dioxygen in methanol proceeds via a two-step mechanism. The initial reaction between (tmeda)Pt(CH(3))(2) and dioxygen yields a hydroperoxoplatinum(IV) intermediate, (tmeda)Pt(OOH)(OC…
We examine some new DNLS-like equations that arise when considering strongly-coupled electron-vibration systems, where the local oscillator potential is anharmonic. In particular, we focus on a single, rather general nonlinear vibrational impurity and determine its bound state(s) and its dynamical selftrapping propert…
The average time for the onset of macroscopic fractures is analytically and numerically investigated in the fiber-bundle model with quenched disorder and thermal noise under a constant load. We find an implicit exact expression for the failure time in the low-temperature limit that is accurately confirmed by direct si…
Polymer-stabilized tetragonal ZrO(2) nanopowders with average size of ca. 2.0 nm have been prepared by microwave heating in an aqueous solution containing Zr(NO(3))(4) x 5H(2)O, PVA, and NaOH. The photoluminescence of the synthesized ZrO(2) fine particles has been investigated.
An extension of the original Overhauser effect to a more general nonequilibrium state was proposed by G. Feher, and demonstrated by Clark and Feher some forty years ago. It is suggested here that it might be possible to produce excess electron spin polarization by allowing the role of the nuclei to be played by other…
We present atomic and defect structural studies of technologically important gold nanorods synthesized by a wet chemical process. Our surface atomic structural studies and electron nanodiffraction from single nanorods have provided the first direct evidence of the stabilization of the highly unstable (110) surface by…
We present here a first systematic study of substituent effects in metallocorroles, based on electronic absorption, resonance Raman (RR), and infrared (IR) spectroscopic studies and electrochemical measurements on 10 copper(III) meso-triarylcorroles, Cu(III)[beta-Y(8)TArC], where the beta-substituent Y = H or Br and t…
ABSTRACT With the development of waterflooding in an oil field, water breakthroughsare a common problem. Polymer solutions are widely applied to resolve thewater-channeling problem in a deep formation. In practice, polymers are used asagents in deep formation treatment either to block in-depth high permeabilityzones o…
Abstract Interwell partitioning tracer test has been recognized as a reliable method for determining residual oil saturation Sorw between wells. While sophisticated streamline or finite difference simulators have been increasingly used to determine Sorw distribution from the tracer data, simple analytical methods such…
Imaging methods, such as micro-focus X-ray (MFX) imaging and magnetic resonance imaging (MRI), have greatly improved our ability to characterise the highly complex internal structures of porous media. MFX imaging and MRI are now both able to provide maps of the spatial distribution of local average accessible porosity…
The structural changes occurring in a 5.2 mol % 1-octene homogeneous ethylene-1-octene copolymer sample during a cooling and heating cycle at 10 °C/min are described in detail using DSC, AFM, SALLS, and synchrotron WAXD and SAXS. The DSC cooling curve exhibits two exothermic maxima where the high-temperature maximum m…
Abstract A UV‐curable polyurethane (PU)‐coating system containing phosphorus is formulated by the combination of photoinitiator, PU acrylate oligomer, and UV‐reactive phosphazene monomer. PU acrylate oligomer is prepared by the addition of 2‐hydroxyethylmethacrylate (HEMA) to NCO‐terminated PU prepolymer. UV‐reactive…
This paper reports the results of applying a computational method called the quantized elastic deformational model, to the determination of conformational flexibility of the supermolecular complex of human fatty acid synthase. The essence of this method is the ability to model large-scale conformational changes such a…
We have performed density functional calculations of the vibrational modes of three tin-based, cagelike clathrate materials: the pure type-I $({\mathrm{Sn}}_{46})$ and type-II $({\mathrm{Sn}}_{136})$ frameworks, and the donor/acceptor compensated compound ${\mathrm{Cs}}_{8}{\mathrm{Ga}}_{8}{\mathrm{Sn}}_{38}.$ We have…