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。
The long-range correction (LC) scheme for the exchange functional of density-functional theory (DFT) was combined with the coupled-perturbed Kohn-Sham (CPKS) method to calculate nonlinear optical response properties. By using this LC-CPKS method, we calculated the hyperpolarizabilities of typical molecules and the dip…
Fiber-shaped H-aggregates with lengths of up to 300 microm are synthesized by self-assembly of thiacyanine (TC) dye molecules in solution. Photoluminescence (PL) images and spatially resolved PL spectra of the fibers that are transferred onto a glass substrate reveal that the fibers act as single-mode optical waveguid…
Reversible addition−fragmentation chain transfer polymerization (RAFT) was used to prepare polymer brushes grafted onto silica nanoparticles. Novel RAFT-silane agents were prepared that contained both an active RAFT moiety and a silane coupling agent. RAFT agents were anchored to silica nanoparticles by the functional…
Current knowledge of toughening mechanisms in zirconia ceramics is reviewed, with particular emphasis on the transformation toughening of yttria-stabilised polycrystalline tetragonal zirconia (Y-TZP). The physics and mechanics of transformation toughening are discussed, but the main aim is to provide a comprehensive u…
We have measured nonresonant and resonant Raman-scattering spectra from ZnO nanocrystals with an average diameter of 20nm. Based on our experimental data and comparison with the recently developed theory, we show that the observed shifts of the polar optical-phonon peaks in the resonant Raman spectra are not related t…
Prior studies suggested that nanoparticle drug delivery might improve the therapeutic response to anticancer drugs and allow the simultaneous monitoring of drug uptake by tumors. We employed modified PAMAM dendritic polymers <5 nm in diameter as carriers. Acetylated dendrimers were conjugated to folic acid as a target…
The ability of several water models to predict the properties of ices is discussed. The emphasis is put on the results for the densities and the coexistence curves between the different ice forms. It is concluded that none of the most commonly used rigid models is satisfactory. A new model specifically designed to cop…
Following our previous study on the stereoselective cocrystallization of linear and cyclic dicarboxylic acid residues in copolyamides 12.6/12.1,4-cyclohexanedicarboxylic acid (12.6/12.1,4-CHDA, Vanhaecht et al., Macromolecules 2004, 37, 421), we have now investigated a series of copolyamides containing trans or cis is…
Precipitation of magnesium hydroxide using narrow channel reactors has been studied. Effects of channel dimensions (two square cross-sectional area channels with areas 1 and 2 mm 2 ), type of mixer (Y and cross mixer), flow rate of the reaction mixture, and reaction parameters on the particle size and particle size di…
Recently, synchrotron-based soft X-ray spectromicroscopy techniques have been applied to studies of polymer microstructure at the ~50 nm spatial scale. Functional group based chemical speciation and quantitative mapping is provided by near edge X-ray absorption fine structure spectral (NEXAFS) contrast. The techniques…
Abstract Structural, thermal, magnetic and solvent‐exchange properties of the spin crossover compound [Fe(bpp) 2 ][Cr(bpy)(ox) 2 ] 2 containing paramagnetic anions are given. This complex salt 1 crystallises as a dihydrate with two inequivalent (high‐spin and low‐spin) Fe II sites. The dehydrated compound is a spin‐cr…
„Anschmiegsam“: Goldnanostäbchen ordnen sich an mehrwandigen Kohlenstoffnanoröhren (MWNTs) aufgrund elektrostatischer Wechselwirkungen einheitlich in Form von Strängen aus Enden-verknüpften Stäbchen an (siehe Bild, PSS=Polystyrolsulfonat, PDDA=Poly(diallyldimethyl)ammoniumchlorid). Es resultiert eine einachsige Plasmo…
We consider the motion of a charged particle near the surface of a single-walled cylindrical nanotube of radius $R$. We formulate the problem by considering the case when the charged particle moves parallel to the axis of the nanotube. We calculate the frictional force on the particle due to the electrostatic interact…
The depth profile of the counterion concentration within thin polyelectrolyte films was measured in situ using contrast variant specular neutron reflectivity to characterize the initial swelling stage of the film dissolution. We find substantial counterion depletion near the substrate and enrichment near the periphery…
Crystalline solids are characterized by long-range positional and orientational order in three dimensions, whereas amorphous liquids lack long-range order in any dimension. Liquid crystals (mesophases) show structural, mechanical and optical properties intermediate to those of crystalline solids and the amorphous, liq…
The synthesis of amphiphilic macromolecules by amidation of hyperbranched polyethylenimine was studied. Amidation with palmitic acid or the methyl ester proceeds up to 84% degree of amidation (140 °C, vacuum). The primary amine end groups react preferentially. With carbonyldiimidazole (CDI)-activated acids nearly comp…
We have calculated the effect of hydrogen adsorption on the work function and surface relaxation of Ti (0001). Calculations were performed for 100% and 25% coverage of the fcc and hcp adsorption sites as well as 100% coverage of both sites. The average of the relaxations obtained with 100% occupation of the fcc or hcp…
Abstract The surface chemistry of hexagonal boron nitride powder is examined. Surface functional groups are found to consist of a mixture of primary and secondary amine groups as well as hydroxyl groups. The surface has a net basic character indicating that the amine contribution to the overall surface chemistry is gr…
Abstract The molecular structures and the spin ground‐state of the iron( ii/iii ) complexes Fe1 , Fe2 and Fe3 , which contain dianionic macrocyclic [N 4 ] ligands derived from substituted acetylacetaldehydes and 1,2‐diamines, have been investigated by X‐ray analysis and temperature‐dependent susceptibility measurement…
This manuscript reports the synthesis and the self-assembly of (4-3,4,5-3,5)nG2-CH2-Boc-l-Tyr-l-Ala-OMe dendritic dipeptides (n = 12, 16). These dendritic dipeptides self-assemble both in solution and in solid states into helical porous supramolecular columns that mimic porous transmembrane proteins. These supramolecu…