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。
While it is known that the elastic properties of a single-walled carbon nanotube (SWNT) are transversely isotropic, the closed-form solutions for all five independent elastic moduli have not been solved completely. In this paper, an energy approach in the framework of molecular mechanics is used to evaluate the local…
A novel class of thermally responsive supramolecular assemblies is formed from the lipophilic cobalt(II) complexes of 4-alkylated 1,2,4-triazoles. When an ether linkage is introduced in the alkylchain moiety, a blue gel-like phase is formed in chloroform, even at very low concentration (ca. 0.01 wt %, at room temperat…
Ultraviolet (UV) fluorescence of Nd3+ ions induced by multistep laser excitation was investigated in Nd-doped LiYF4 and LiLuF4 crystals using a technique of time-resolved spectroscopy. The observed UV luminescence was due to transitions between the bottom of 4f25d configuration and the 4f3 states of Nd3+ ions. The fir…
A crystalline microporous semiconductor |(|K6(H2O)6| [Sb12O18])3| [Te36] (denoted SBC-1) has been prepared, which consists of 24-ring tubular tellurium units that host 12-ring {Sb12O18} tubular units, which in turn act as hosts for K+ ions and H2O molecules (see picture). An example of a second-order zeoate, it has a…
Thin solid films of hydroxypropylcellulose (HPC) have been investigated using synchrotron X-ray reflectivity. Evidence of preferential alignment of HPC molecules at the substrate surface is obtained. In the surface region the liquid crystalline domains ofHPC are preferentially oriented parallel to the substrate, where…
Abstract Plerospheres, defined here as superfine spherical particles (0.5–5 μm) separated from fly ash (rather than as other solid spherical particles, as some have used the term), are separated from coal fly ash but are dramatically different from it. Plerospheres can be used as polymer fillers to improve the propert…
Raman scattering measurements were made on polycrystalline Mn0.62Zn0.30Fe2.08O4 ferrites with various degrees of stress generated during the polishing process, in the temperature range from 175 to 603 K. Raman spectra were found at energies of 337, 464, and 620 cm−1 in substrates with low stress. The integral intensit…
Abstract The objective was to study the photocationic polymerization of an expanding monomer, 1,5,7,11‐tetraoxaspiro[5.5]undecane (TOSU), and an aromatic dioxirane, bisphenol A diglycidyl ether (BADGE). Both homopolymerizations and binary polymerizations were conducted. The homopolymer, poly(TOSU), was found to be a l…
Within an intense research study concerning the theme “organization and reorganization of solution grown polyethylene single crystals”, the present part is focused on the nucleation and growth behavior of such crystals. Beside the well-known crystallization behavior, several novel features have been observed. Growth r…
Flüssigkristalle aus großen Graphitsegmenten: Diskotische Verbindungen, basierend auf substituierten Superphenalenen, wurden auf einfachem Weg hergestellt und in ungewöhnlicher Weise zu weichen und sehr gut löslichen columnaren flüssigkristallinen Phasen weiterverarbeitet. Die regiospezifische Synthese führt zu einer…
A class of silicon carbide cage clusters with two carbon atoms inside the silicon cage and with high stabilities are presented. The theoretical formalism used is Hartree-Fock theory followed by second-order many-body perturbation theory to account for correlation effects, and geometry optimizations at the second-order…
The interfacial tension σ between two polyisobutylenes (PIB) of dissimilar polydispersity and two polydisperse samples of poly(dimethylsiloxane) (PDMS) was measured as a function of time by means of a pendent drop apparatus at different temperatures ranging from 30 to 110 °C. In addition to three of the four possible…
The electromechanical performance characteristics of electrostrictive 0.9 Pb(Mg1/3Nb2/3)O3–0.1 PbTiO3 and piezoelectric 0.7 Pb(Mg1/3Nb2/3)O3–0.3 PbTiO3 ceramics have been investigated under uniaxial stress (σ). The results demonstrate that the large-signal electromechanical properties of electrostrictive ceramics are…
Pinning down flavoproteins: A designed β-hairpin peptide binds flavin mononucleotide (FMN) in water through noncovalent interactions involving Trp and Lys residues on one face of the β hairpin (see model). Reduction of FMN is disfavored in the complex as a result of favorable π–π stacking interactions between Trp side…
We investigate the role of axial ligands on the near-IR-optical and paramagnetic NMR spectra of the complex [YbL](+3) where L is the stereodefined enantiopure chiral macrocycle (L = hexaazapentacyclo[25.3.1.1(12,24).0(4,9).0(19,24)]dotriaconta-1(31),2,10,12,14,16(32),17,25,27,29-decaene). The conformation in solution…
Abstract Steady shear viscosities of blends of poly(butyl acrylate) and cholesteryl oleyl carbonate were studied under a cone and plate fixture. Unique shear behavior was observed for the polymer/low molar mass liquid crystal mixture. The viscosity of the liquid crystal‐rich phase increases with polymer content until…
The thermoelectric properties, including electrical resistivity (ρ), Seebeck coefficient (S), and thermal conductivity (κ) on binary icosahedral Cd-Yb quasicrystals and Cd6Yb are investigated. The Cd-Yb quasicrystals have a room-temperature (RT) resistivity value of about 200 (μΩ cm), however, the temperature-dependen…
We produced single bubbles in water using a visible pulsed laser and studied the characteristics of the light emitted during the bubble collapse time as a function of the water temperature for different water purity values. The water temperature ranged from freezing point (0 °C) to near boiling. We measured the lumine…
The diameter distribution of the nanotubes produced by electric-arc discharge are measured using Raman spectroscopy at various wavelengths. These measurements agree with the results provided by two other techniques: high-resolution transmission electron microscopy and x-ray diffraction. The mean tube diameter shifts m…
Abstract The reaction of isophorone diisocyanate (IPDI) with poly(hexane neopentyl adipate glycol) (HNA) and dimethylol propionic acid (DMPA) was researched through an analysis of the contents of the NCO groups of the prepolymers through which water‐borne polyurethanes (PUs) could be formed. The reaction activity of D…