Materials Literature
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We analyze Ge-related defects in Ge-doped SiO_2 using first-principles density functional techniques. Ge is incorporated at the level of ~ 1 mol % and above. The growth conditions of Ge:SiO_2 naturally set up oxygen deficiency, with vacancy concentration increasing by a factor 10^5 over undoped SiO_2, and O vacancies…
We report direct first-principles density-functional calculations of the piezoelectric tensor $\tensor{d}$ relating polarization to applied stress for the binary compounds AlN, GaN, and InN. The values of $\tensor{d}$ are rather sensitive to the choice of the exchange-correlation functional, and results are presented…
Because the physical interpretation of the spin-polarization of a ferromagnet determined by point-contact Andreev reflection (PCAR) is non-trivial, we have carried out parameter-free calculations of PCAR spectra based upon a scattering-theory formulation of Andreev reflection generalized to spin-polarized systems and…
We introduce a fiber bundle model where the interaction among fibers is modeled by an adjustable stress-transfer function which can interpolate between the two limiting cases of load redistribution, the global and the local load sharing schemes. By varying the range of interaction several features of the model are num…
We identify the W center in self-implanted crystalline Si with the three-membered self-interstitial cluster I_3 on the basis of first-principles density-functional-theory calculations matching all the known experimental signatures of the center (emission energy, extrinsic energy levels, activation energy and dissociat…
Mössbauer spectra of [LFe(II)X](0) (L = beta-diketiminate; X = Cl(-), CH(3)(-), NHTol(-), NHtBu(-)), 1.X, were recorded between 4.2 and 200 K in applied magnetic fields up to 8.0 T. A spin Hamiltonian analysis of these data revealed a spin S = 2 system with uniaxial magnetization properties, arising from a quasi-degen…
MS-325 is a novel blood pool contrast agent for magnetic resonance imaging currently undergoing clinical trials to assess blockage in arteries. MS-325 functions by binding to human serum albumin (HSA) in plasma. Binding to HSA serves to prolong plasma half-life, retain the agent in the blood pool, and increase the rel…
The angular and energy dependencies of the exchange interaction between the electrons in an itinerant ferromagnetic surface can be mapped out by exciting two interacting spin-polarized electrons into the vacuum and resolving at the same time the energies and emission angles of the two electrons. From a tensorial symme…
Two different types of three-generation hyperbranched graft surfaces with parent chain (stem), daughter chain (branch chain), and granddaughter chain (twig chain) were sequentially prepared by iniferter ( ini tiator−trans fer agent− ter minator)-based quasi-living radical graft copolymerization using photolysis of the…
The previously unknown crystal structure of the local anaesthetic tetracaine hydrochloride (C15H25N2O2+Cl−) has been solved from synchrotron X-ray powder diffraction data using a direct-space global optimisation method in which the position and conformation of a structural model is adjusted. The C15H25N2O2+ moiety and…
Abstract This article describes the synthesis and characterization of polyisobutylene (PIB) carrying one primary hydroxyl head group and a tertiary chloride end group, [PhC(CH 3 )(CH 2 OH)–PIB–CH 2 C(CH 3 ) 2 Cl] prepared with direct functionalization via initiation. The polymerization of isobutylene was initiated w…
Low-temperature luminescence measurements under high pressures in diamond-anvil cell of nonstoichiometric lanthanum lutetium gallium garnet (LLGG) doped with ${\mathrm{Cr}}^{3+}$ ions and nonintentionally with ${\mathrm{Nd}}^{3+}$ ions are reported. Three nonequivalent ${\mathrm{Cr}}^{3+}$ centers were found in the cr…
Carrier transits and photoconductivity in hexaalkoxytriphenylene- (HAT) based liquid crystals and their binary 1:1 mixtures with hexaalkylphenyltriphenylene (PTP) are analyzed using time-dependent diffusion theory. The HAT6 derivatives, which show the best transits, can be modeled with a homogeneously distributed sing…
ePTFE membranes were modified by poly(ethylene glycol) having a molecular weight of 600 (PEG-600) in atmospheric pressure glow discharge (APG) plasma treatment. ePTFE membranes were immersed in 1%, 3%, or 5% (w/v) PEG-600 in dehydrated ethanol. PEG-600-penetrated ePTFE membranes were dried in a vacuum to immediately r…
Nanometer-sized europium-doped calcium sulfide (CaS–Eu) particles were synthesized for the first time for potential use in bioassays, in particular, in biochip-based analysis. The CaS–Eu nanoparticles were prepared through a wet chemical process in ethanol. The average diameter of the nanoparticles was about 15 nm. Th…
Highly periodic hexagonal honeycombs of platinum-germanium chalcogenide and platinum-tin selenide frameworks were prepared by linking corresponding [Ge(4)Q(10)](4)(-) (Q = S, Se) and [Sn(4)Se(10)](4)(-) clusters with Pt(2+) ions. The non-oxidic honeycombs designated as C(n)PyPtGeQ and C(n)PyPtSnSe were templated by th…
Abstract A new diamine monomer, 4,4″‐bis(aminophenoxy)‐3,3″‐trifluoromethyl terphenyl (ATFT) was synthesized that led to a number of novel fluorinated polyimides by solution as well as thermal imidization routes when reacted with different commercially available dianhydrides like pyromellatic dianhydride (PMDA), benzo…
The effect of acetylacetone (acac) complexing ligand on the formation and growth of tin oxide-based nanoparticles during thermohydrolysis at 70 °C of a tin precursor SnCl 4 - n (acac) n (0≤ n ≤ 2) solution was analyzed by in situ small-angle X-ray scattering. A transparent and stable sol was obtained after 2 h of ther…
This letter describes the preparation and characterization of a novel porous ceramic material via the burning of the polylactide/layered silicate nanocomposite. WAXD patterns indicate that an amorphous structure was developed in the porous ceramic material after sintering the nanocomposite. SEM observation revealed a…
The conjugation of nanoparticles (NPs) typically yields supramolecular materials which are fairly rigid, and the electronic coupling between the NP and other structural units of these compounds is fixed by covalent bonds. Here, we report on a novel bichromophor system constructed from a quantum dot tethered to a semic…