Materials Literature
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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…
A continuum field theory approach is presented for modeling elastic and plastic deformation, free surfaces, and multiple crystal orientations in nonequilibrium processing phenomena. Many basic properties of the model are calculated analytically, and numerical simulations are presented for a number of important applica…
Abstract A series of poly(butylene terephthalate) copolyesters containing 5‐ tert ‐butyl isophthalate units up to 50 mol %, as well as the homopolyester entirely made of these units, were prepared by polycondensation from a melt. The microstructure of the copolymers was determined by NMR to be random for the whole ran…
Abstract For Abstract see ChemInform Abstract in Full Text.
Spiral alumina nanowires, doped with Cr and Si, are directly and reliably produced in bulk quantities via annealing of high entropy alloys.
YfiT, a 19-kDa polypeptide from Bacillus subtilis, belongs to a small sequence family with members predominantly from Gram positive bacteria. We have determined the crystal structure of YfiT in complex with Ni(2+) to a resolution of 1.7 A. YfiT exists as a dimer and binds Ni(2+) in a 1:1 stoichiometry. The protein has…
One common method of illicit methamphetamine manufacture utilizes an alkali metal, typically lithium, and liquid ammonia to chemically reduce ephedrine or pseudoephedrine to form methamphetamine. This method is often referred to as the lithium-ammonia reduction method or the Birch reduction method. While the hydroxyl…
The synthesis and structural characterisation of a thermally stable novel three-dimensional microporous copper silicate open-framework are described; the material is capable of undergoing reversible zeolitic water removal without destruction of the framework.
Abstract Glass transition, cold crystallization, and melting of freeze‐dried poly(L‐lactide) (PLLA) prepared from dilute 1,4‐dioxane solutions were investigated by differential scanning calorimetry (DSC). Conventional DSC measurements of heating scans revealed that freeze‐dried PLLA prepared from a 0.07 wt % solution…