Materials Literature
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A chemical route to single-walled carbon nanotubes (SWCNTs) under ambient conditions has been developed. Silica powder was immersed in a mixture solution of ferrocene and p-xylene. After sonication at atmospheric pressure and room temperature, we obtained high-purity SWCNTs. Sonochemical effects may lead to producing…
The single-step synthesis of silver nanoparticles by the reduction of silver ions present in the subphase under alkaline conditions by 3-pentadecylphenol (3-PDP) Langmuir monolayer and their assembly into ordered two-dimensional structures is described. The reduction of the silver ions occurs by electron transfer from…
The adsorption and reactivity of methanol on TiO 2 anatase(101) surfaces are studied through first-principles total energy calculations and Car−Parrinello molecular dynamics simulations. The effects of different methanol coverages up to one monolayer and different surface oxidation states are investigated. The most st…
Single-crystal nanoparticles of silicon, several tens of nanometres in diameter, may be suitable as building blocks for single-nanoparticle electronic devices. Previous studies of nanoparticles produced in low-pressure plasmas have demonstrated the synthesis of nanocrystals 2–10 nm diameter but larger particles were a…
Polymer-clay nanocomposites are a newer class of flame retardant materials of interest due to their balance of mechanical, thermal and flammability properties. Much more work has been done with natural clays than with synthetic clays for nanocomposite flammability applications. There are advantages and disadvantages t…
The new compound [Ag(2)(bptz)(3)][AsF(6)](2), prepared from the reaction of bptz with Ag[AsF(6)] in CH(3)CN, is stable in solution as well as the solid-state and exhibits an unprecedented propeller arrangement of three bptz ligands spanning two Ag(i) ions with [AsF(6)](-) anions located in the folds of the cation.
The crystallization kinetics of each constituent of poly(p-dioxanone)-b-poly(epsilon-caprolactone) diblock copolymers (PPDX-b-PCL) has been determined in a wide composition range by differential scanning calorimetry and compared to that of the equivalent homopolymers. Spherulitic growth rates were also measured by pol…
A series of molecules, based on the smallest carbon cluster with one planar tetracoordinate carbon atom, C5(2-), are presented. To gain a better understanding about which electronic factors contribute to their stabilization, several global reactivity indexes, molecular scalar fields, and magnetic responses were calcul…
Abstract New polyamides, containing a benzimidazole side group and ethylene oxide moieties in the structural repeat unit, were synthesized by low‐temperature polycondensation. The aim of this design was to obtain polyamides that were more soluble in common organic solvents and hence had better processability than benz…
A calix[4]pyrrole incorporating four appended tetrathiafulvalene (TTF) units has been synthesized, and its receptor abilities toward neutral electron-deficient guests, such as 1,3,5-trinitrobenzene, tetrafluoro-p-benzoquinone, and tetrachloro-p-benzoquinone, have been studied in solution by UV-vis and 1H NMR spectrosc…
The electronic structures of carbon (C) and boron nitride (BN) nanotubes under a transverse electric field were investigated through the first-principles pseudopotential density-functional theory (DFT) calculations. It was found that band gap modifications occur both in the semiconducting C and BN nanotubes under an e…
We have developed a technology to reproducibly make gaps with distance control on the single atom scale. The gold contacts are flat on the nanometre scale and are fabricated on an oxidized aluminium film that serves as a gate. We show that these contacts are clean and can be stabilized via chemical functionalization.…
Spatially resolved neutron diffraction as a function of crystal depth in $\mathrm{Pb}({\mathrm{Mg}}_{1∕3}{\mathrm{Nb}}_{2∕3}){\mathrm{O}}_{3}$ reveals the presence of a distinct near-surface region where a strong distortion in the lattice exists. A dramatic change in both the lattice constant and the Bragg peak intens…
By following the trajectories of quantum particles inside a periodic lattice and preserving their classical probabilities for reflection, transmission and absorption at each lattice plane, classical scattering outcomes are obtained. Diffraction phenomena in crystals are reproducible after assigning probability amplitu…
Ultra-precise lattice parameter measurements in single crystals are achievable, in principle, by X-ray multiple diffraction (XMD) experiments. Tiny sample misalignments have hindered the systematic usage of XMD in studies where accuracy is an important issue. In this work, theoretical basement and methods for correcti…
The first-order reversal curve (FORC) method is applied to the two-dimensional kinetic Ising model. For the system size and magnetic field chosen, the system reverses by the homogeneous nucleation and growth of many droplets. This makes the dynamics of reversal nearly deterministic, in contrast to the strongly disorde…
We demonstrate how the Rashba spin-orbit coupling in semiconductor heterostructures can produce and control a spin-polarized current without ferromagnetic leads. Key idea is to use spin-double refraction of an electronic beam with a nonzero incidence angle. A region where the spin-orbit coupling is present separates t…
Following the theoretical predictions of ferromagnetism in Mn- and Co-doped ZnO, several workers reported ferromagnetism in thin films as well as in bulk samples of these materials. While some observe room-temperature ferromagnetism, others find magnetization at low temperatures. Some of the reports, however, cast con…
Abstract An overview is presented of the literature on the flame retardancy of thermoplastic polyesters, especially poly(ethylene terephthalate) (PET) and poly(butylene terephthalate) (PBT). The main focus is on publications of the last fifteen years; however, some earlier work of major importance is discussed as well…
Porphyrin nanotubes are made by ionic self-assembly of two oppositely charged synthetic porphyrin molecules. The diameter of the nanotubes can be altered by modifying the structure of one of the porphyrin tectons. The nanotubes are photocatalytically active, mechanically responsive to light, and are composed of J-aggr…