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。
ADVERTISEMENT RETURN TO ISSUEPREVNoteNEXTSynthesis and Aqueous Solution Characterization of Catalytically Active Block Copolymers Containing ImidazoleMartin R. Simmons and Costas S. PatrickiosView Author Information Department of Chemical Engineering, University of Manchester Institute of Science and Technology (UMIST…
Poly(vinylidene flouride) (PVF 2 ) gels in diethyl adipate (DEA) with fibrillar morphology. The gels are transparent. The Wide-angle X-ray scattering pattern and FT-IR spectra of the gel indicate the presence of solvated α-phase PVF 2 crystallites in the gel. The intensities of the X-ray diffraction peaks of the gel a…
A new method for the surface derivatization of gold colloidal particles is reported. The method is based on the aqueous solubilization of aliphatic thiols by α-cyclodextrin, which effectively binds to the aliphatic chains and carries the hydrophobic thiol molecules to the surface of the gold particles, where they unde…
The backbone 15 N− 1 H 1 J values have been measured for oxidized and reduced cytochrome b 5 at 500 and 800 MHz. Their field dependence, due to increasing partial orientation of the molecule in solution at high magnetic fields, provides structural constraints relative to the orientation of the NH bond vector with resp…
The Kolmogorov-Johnson-Mehl-Avrami (KJMA) theory for the time evolution of the order parameter in systems undergoing first-order phase transformations has been extended by Sekimoto to the level of two-point correlation functions. Here, this extended KJMA theory is applied to a kinetic Ising lattice-gas model, in which…
We present a theoretical prediction of a new mechanism for carrier population inversion in semiconductors under an applied electric field. The mechanism is originated from a coherent capture-emission type inelastic scattering of resonant states. We support our theory with concrete calculations for shallow acceptor res…
We consider a tight-binding Hamiltonian defined on the quasiperiodic Ammann-Beenker tiling. Although the density of states (DOS) is rather spiky, the integrated DOS is quite smooth and can be used to perform spectral unfolding. The effect of unfolding on the integrated level-spacing distribution is investigated for va…
The absorptive and emissive behavior of four highly fluorescent bisalkyl-substituted poly( p- phenyleneethynylenes) (R = hexyl, dodecyl, 2-(ethyl)hexyl, and 3,5,5-trimethylhexyl) was examined. Aggregate and excimer formation was seen in solution and in the solid state by a combination of absorption and fluorescence sp…
Sp3-hybridized semiconductors (including InP, GaAs, CdSe, and Si) are remarkable from the perspective of physical chemistry. A single electron created by HOMO-LUMO promotion moves rapidly in response to an applied
Three generations of ester-terminated dendrimers have been constructed from (1 R,2 S )-2-amino-1-phenyl-1,3-propanediol, 1, as the central core. The chiroptical properties of the dendrimers were measured revealing that the molar rotations [Φ] of the dendrimers decreased with increasing dendrimer generation. Comparison…
19 F NMR measurements on lithium perfluorononanoate [LiPFN] in D 2 O and in solutions of D 2 O with poly(vinylpyrrolidone) [PVP] at different molecular weights have been carried out. A careful study of literature data and COSY maps allowed the full assignment of the 19 F resonances as a function of concentration and c…
The ion pair charge-transfer (IPCT) complexes (C(14)H(12)N(2))[Cu(opba)].3H(2)O (1) and Na(2)(C(12)H(12)N(2))[Cu(opba)](2).4H(2)O (2), opba = o-phenylenebis(oxamate), have been isolated. Both compounds crystallize in the triclinic space group P&onemacr;. Crystal data for the compounds 1, a = 7.3216(13) Å, b = 10.1756(…
Hollow microspheres of titanium dioxide have been prepared by spray-drying a colloidal suspension of an exfoliated titanate followed by heating above 400 °C. The individual hollow sphere with a diameter of tens of micrometers is characterized by its extremely thin crust, tens of nanometers thick. Because 99% of the pa…
The structure of AgCl formed in the course of chlorine adsorption on Ag(111) surface was studied by STM. For the first time atomic resolution STM images of silver chloride were obtained. The silver chloride was detected as small (30-60 A in diameter) islands located on the atomic terraces. The upper plane of the islan…
We study the influence of implantation parameters (temperature, implanted dose, and current density) on the microstructure of carbon onions produced by carbon ion implantation into silver substrates held at elevated temperature. Carbon onions are synthesized only for temperatures higher than 400 °C. An increase of the…
We have studied n-type silicon containing gold and gold–hydrogen complexes using high-resolution “Laplace” deep-level transient spectroscopy. This technique has enabled two quite distinct electron emission rates to be observed at temperatures between 240 and 300 K. These are associated with the gold acceptor and the l…
We report an optical reflectivity study of charge and spin ordering in ${\mathrm{Bi}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{MnO}}_{3}$ ( $x\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.74$ and 0.82) single crystals. In the high temperature phase, $T>{T}_{\mathrm{co}}$, which is characterized by ferroma…
The first study of thermal conductivity, $\ensuremath{\kappa}$, in a quasi-two-dimensional organic superconductor of the $\ensuremath{\kappa}\ensuremath{-}(\mathrm{BEDT}\ensuremath{-}\mathrm{TTF}{)}_{2}X$ family reveals features analogous to those already observed in the cuprates. The onset of superconductivity is ass…
When we use a scanning electron microscope-molecular beam epitaxy system with a GaAs (111)A substrate that dramatically improves the flatness of the growing surface, it makes possible detailed observations of the near-equilibrium growth processes of island nucleation, coalescence, and step motion. These observations a…
Semiconductor quantum dots and wires are the subject of great interest, mainly due to their size-dependent electronic structures, in particular increased band gap and therefore optoelectronic properties. We have electrodeposited films of size-quantized CdS (∼4 to 5 nm cross section by 15 nm height) as a buffer layer o…