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。
Abstract Polyaluminocarbosilane (PACS) as the precursor of high‐temperature resistant SiC fibers was synthesized by reacting polycarbosilane (PCS) with aluminum(III)acetylacetonate [Al(AcAc) 3 ] at 310°C in N 2 under ambient pressure. The reaction mechanism and the structure of PACS were investigated in detail by FTIR…
Abstract Conducting polymers such as polyaniline and polypyrrole exhibit novel sensoric properties and are able to interact chemically or electrochemically with the species of interest for detection. In the current investigation, construction of a sensor based on an electrochemical reaction between Cr VI and a thin la…
The adsorption properties of a rake-type siloxane surfactant (consisting of a poly(dimethylsiloxane) backbone with grafted polyether) on carbon black (CB) nanoparticles have been investigated. The CB particles have fractal structure according to transmission electron microscopy and small-angle neutron scattering (SANS…
The unusually broad diameter distribution of single wall carbon nanotubes (SWCNTs) in a HiPCO derived sample made it possible to observe for the first time a selective loss of Raman resonances corresponding to large diameter tubes upon both p- (FeCl3) and n-type (K) doping.
We present coupled electronic oscillator calculations on conjugated dendrimers that can be used in organic light-emitting diodes. The results indicate that the nature of the excited state in these materials can be strongly influenced by electronic coherences. We use the collective electronic oscillator model approach…
Abstract Branched poly(ether sulfone)s were prepared from 1,1,1‐tris(4‐hydroxyphenyl) ethane and 4,4′‐difluorodiphenyl sulfone (DFDPS) either by polycondensation in dimethyl sulfoxide with the elimination of water or via the silyl method in N ‐methylpyrrolidone. With an exact 1/1 stoichiometry, crosslinking was avoida…
A series of well-defined dumbbell copolymers of (PBd) 32 PS(PBd) 32 type, with the same polystyrene (PS) connector (10 600 g/mol) and 32 polybutadiene (PBd) branches of varying molecular weight (1200, 5000, 15 000, 43 000 g/mol) on each end, were synthesized, and their viscoelastic properties were investigated. For th…
Abstract The electrical resistivity of low‐density polyethylene/carbon black composites irradiated by 60 Co γ‐rays was investigated as a function of temperature. The experimental results obtained by scanning electron microscopy, solvent extraction techniques, and pressure‐specific volume‐temperature analysis technique…
The influence of structured organic surfaces on the oriented overgrowth of inorganic crystals is a fundamental aspect of biomineralization. This paper describes the dramatic changes in the crystallization of calcium carbonate within thermally evaporated stearic acid films by varying the pH of the electrolyte solution.…
Polymeric functional thin films have been deposited from plasmas of allyl alcohol, acrylic acid, allylamine and octa-1,7-diene onto polystyrene microwells and aluminium foil, and analysed by X-ray photoelectron spectroscopy (XPS) and water contact angle measurement. The films were found to be conformal and pin-hole fr…
Questions surrounding the spatial disposition of particles in various condensed-matter systems continue to pose many theoretical challenges. This paper explores the geometric availability of amorphous many-particle configurations that conform to a given pair correlation function g ( r ). Such a study is required to ob…
The use of cyclen (1,4,7,10-tetraazacyclododecane) as a blocking ligand enables assembly of the mixed-valence square complex [(cyclen)4Ru4(pz)4]9+ (pz = pyrazine). A crystal structure determination shows the molecule to possess a regular square geometry wherein each Ru atom has an equivalent coordination environment.…
Dinuclear manganese(II), cobalt(II), nickel(II), and copper(II) complexes bridged by pyrimidine and pyrazine derivatives, L[M(hfac)2]2 [L = 4,6-di(2-pyridyl)pyrimidine (DPPM), 2,3-di(2-pyridyl)pyrazine (DPPZ); M = Mn, Co, Ni, Cu; hfac = 1,1,1,5,5,5-hexafluoropentane-2,4-dionate], were synthesized and their magnetic pr…
Two novel A−B−A type amphiphilic triblock copolymers, namely poly( N -(2-hydroxypropyl)methacrylamide)- block -poly(ε-caprolactone)- block -poly( N -(2-hydroxypropyl)methacrylamide) (PHPMA- b -PCL- b -PHPMA) and poly( N -vinyl-2-pyrrolidone)- block -poly(ε-caprolactone)- block -poly( N -vinyl-2-pyrrolidone) (PVP- b -P…
The influence of gravity on the capillary forces and stabilities of pendular liquid bridges between spherical bodies is examined including the special case of a sphere and a flat surface. Previously, this has only been possible by measurement or calculation for a particular bridge system. In the current work, it is sh…
A novel type of hollow zeolite capsules has been fabricated through a facile route involving the vapor-phase transport (VPT) treatment of the silicalite-1 seeds precoated mesoporous silica (MS) spheres. The properties of the capsule interiors can be easily tailored by encapsulating desired guest species that have been…
We study the properties of heterostructures formed by two layers of diluted magnetic semiconductor separated by a nonmagnetic semiconductor layer. We find that there is a RKKY-type exchange coupling between the magnetic layers that oscilles between ferromagnetic and antiferromagnetic as a function of the different par…
LiBC, a semiconducting ternary borocarbide constituted of the lightest elements only, has been synthesized and characterized by x-ray powder diffraction, dielectric spectroscopy, and conductivity measurements. Utilizing an infrared microscope the phonon spectrum has been investigated in single crystals. The in-plane B…
Quantum computation in molecular magnets is studied by solving the time-dependent Schr\"odinger equation numerically. Following Leuenberger and Loss [Nature (London) $410,$ 789 (2001)], an external alternating magnetic field is applied to populate and manipulate a superposition of single-spin states in molecular magne…
The adsorption on silica wafers of a hyperbranched, high molecular weight polyethylenimine (PEI) was investigated using reflectometry. The pH and ionic strength dependence of PEI adsorption kinetics and that of the adsorbed amount were interpreted according to the complex balance of segment/segment and segment/surface…