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。
[reaction: see text] Nineteen Mn(II) complexes were screened for the catalytic epoxidation of terminal olefins using peracetic acid. Few of these complexes are efficient catalysts at pH < 2, but many are effective at 1 mol % catalyst loading at pH 4. With 0.1 mol % loading, four complexes epoxidize 1-octene in approxi…
Luminescence temperature antiquenching (LTAQ) is observed for water-soluble CdTe quantum dots (QDs) capped with aminoethanethiol (AET). The efficient exciton emission (quantum efficiency of approximately 40% at 300 K) is quenched almost completely as the QD solutions are cooled to below 230 K and is fully recovered ar…
Flat arrays (rafts) of aligned silver nanowires were fabricated by electrodepositing silver in the nanopores of highly ordered anodic alumina templates and then releasing the silver nanowires and depositing them on an oxidized, single-crystal silicon surface. SERS spectra were recorded from Rhodamine 6G molecules adso…
ZnS nanowaveguides with rectangular cross-section (∼50 × 50 nm 2 ) and tens of microns in length have been synthesized by pulsed laser vaporization of ZnS/10% Au targets in a flow of Ar/5% H 2 . The highly crystalline filaments exhibit the wurtzite structure, growing mainly along the [001] or [100] directions. Photolu…
The development of thin films and coatings that control the release of DNA from the surfaces of materials could have a significant impact on localized approaches to gene therapy. Here, we report multilayered polyelectrolyte assemblies that sustain the release of functional plasmid DNA from the surfaces of model substr…
Abstract Air‐filled microballoons of poly(dimethylsiloxane), ie PDMS, have been encapsulated in polyimide. The molecular assembly so formed has shown surface dominance by PDMS while analytical techniques, such as X‐ray photoelectron spectroscopy and infrared spectroscopy, have confirmed a similar distribution in the b…
Abstract Poly(3‐hydroxybutyrate‐ co ‐3‐hydroxyvalerate) (PHBV) was irradiated by 60 Co γ‐rays (doses of 50, 100 and 200 kGy) under vacuum. The thermal analysis of control and irradiated PHBV, under vacuum was carried out by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The tensile prope…
Abstract A new series of segmented copolymers were synthesized from poly(ethylene terephthalate) (PET) oligomers and poly(ethylene glycol) (PEG) by a two‐step solution polymerization reaction. PET oligomers were obtained by glycolysis depolymerization. Structural features were defined by infrared and nuclear magnetic…
(S)-Mandelate dehydrogenase from Pseudomonas putida belongs to a FMN-dependent enzyme family that oxidizes (S)-alpha-hydroxyacids. Despite a high degree of sequence and structural similarity, this family can be divided into three subgroups based on the different oxidants utilized in the second oxidative half-reaction.…
The origin of a deep pseudogap existing at the Fermi level ${E}_{\mathrm{F}}$ in the ${\mathrm{Al}}_{52.5}{\mathrm{Li}}_{32.5}{\mathrm{Cu}}_{15}$ $1∕1\text{\ensuremath{-}}1∕1\text{\ensuremath{-}}1∕1$ approximant was studied from two different points of view of orbital hybridizations and the Fermi surface--Brillouin zo…
The reaction between adsorbed CO molecules and O atoms on epitaxially grown RuO 2 (110) was investigated by scanning tunneling microscopy. Two types of titration experiments were performed at 300 K, in which either CO was dosed on the stoichiometric oxide surface, or O 2 on the CO saturated surface. In both cases, rea…
The dilution effects of the precursor methane atmosphere by three noble gases (Ar, Ne and He) on the mechanical properties and the microstructure of hydrogenated amorphous carbon films deposited by rf-PECVD were studied. The chemical composition and atomic density of the films were determined by ion beam analysis. The…
Amorphous carbons have been prepared by plasma deposition in a vacuum and in the presence of a variety of gases. On subsequent heating in a vacuum, ultraviolet absorption spectra of certain of these materials show the development of a feature centered at 2175 Å (4.6 μm -1 ). We find that the spectrum of amorphous carb…
The synthesis of 4‘-hydroxyphenyl(4-hydroxy-3-allyl)azobenzene is reported. The molecule is mesogenic and it can be used for preparing nematic main-chain segmented polymers. The nematic phase is the result of the effect of the side allyl group which, while it destabilizes the crystalline phase, does not affect the occ…
Polymers are often blended with additives (e.g., polymers, clays) to produce composite materials having desirable physical properties that reflect synergy between the blend constituents. Though polymer blends with small-molecule nematic liquid crystal phases have been investigated (primarily for displays), related mat…
A systematic study based on an ab initio calculation within a local spin density approximation is applied to material design of GaAs- and GaP-base doped by 3 d transition metals. It is found that the ferromagnetic (FM) state is ready to achieve by V-, Cr- and Mn-doped GaP and GaAs. (Ga, Cr)P and (Ga, Cr)As are the mos…
To date, a number of ceramic oxides with the perovskite structure have been proposed as membrane materials for the selective separation of oxygen and the partial oxidation of hydrocarbons due to their high oxygen permeation fluxes. In contrast, their instability under an oxygen pressure gradient and consequent lattice…
Abstract A series of odd‐odd polyamides were prepared through step‐heating melt‐polycondensation of undecanedioic acid with various diamines. The synthesized nylons were characterized comprehensively by means of elemental analysis, fourier‐transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR), Raman…
Abstract Poly(ethylene terephthalate) (PET) and poly(ethylene glycol) (PEG) copolymers crosslinked with glycerol and sulfoisophthalate (SP) were prepared to investigate the feasibility of fabricating smart vibration‐controlling composite laminate. The composition of glycerol and SP was varied to get a copolymer with t…
The hydrogen motion in poly(vinyl ethylene) (1,2-polybutadiene) in the alpha-relaxation regime has been studied by combining neutron spin echo (NSE) measurements on a fully protonated sample and fully atomistic molecular dynamics simulations. The almost perfect agreement between experiment and simulation results valid…