Materials Literature
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Abstract To investigate the intramolecular van der Waals interactions between two divalent selenium centers in the solid state and in solution, we have prepared methyl 2‐(methylselenyl)benzyl selenide ( 1 ), ethynyl 2‐(methylselenyl)benzyl selenide ( 2 ), and 2‐(methylselenyl)benzyl selenocyanate ( 3 ). By means of NM…
Using electron diffraction, we show that free-electron metals, such as sodium and potassium, form a highly regular quasiperiodic monolayer on the fivefold surface of icosahedral Al-Pd-Mn and that the quasiperiodicity propagates up to the second layer in sodium. Our photoelectron spectroscopy results show that the quas…
A two-probe system of the heterojunction formed by an (8, 0) carbon nanotube (CNT) and an (8, 0) silicon carbide nanotube (SiCNT) was established based on its optimized structure. By using a method combining nonequilibrium Green's function (NEGF) with density functional theory (DFT), the transport properties of the he…
Chiral non-racemic perazamacrocyles containing three or more nitrogen atoms in the form of different functions (amine, amide, imine) are prepared from optically active amines, diamines, α-aminoacids, and their derivatives, by properly selected methodologies. The many applications of these optically pure perazamacrocyc…
CdTe nanocrystalline thin films have been prepared on glass, Si and Al2O3 substrates by radio-frequency magnetron sputtering at liquid nitrogen temperature. The crystal structure and morphology of the films were characterized by X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM). The XRD e…
A prismatic layer is present in both freshwater-cultured pearls and seawater-cultured pearls. The phase structure of the prismatic layer of freshwater-cultured pearls is investigated for the first time and novel findings are reported in this paper. X-ray diffraction (XRD), optical microscopy (OM) and micro-infrared (I…
A new family of polynuclear clusters containing the Fe(III)(3)M(II) cores [(Tp(4Bo))(6)Fe(6)(CN)(18)M(2)Na(2)(H(2)O)(16)] x 4 H(2)O (M = Cu, Co, Mn; 1-3) and [(Tp(4Bo))(6)Fe(6)(CN)(18)M(2)Na(2)(H(2)O)(12)(DMF)(4)] x H(2)O (M = Cu, Co, Mn; 4-6) have been synthesized and structurally characterized. Complexes 1-3 crystal…
Chitosan has received considerable attention for biomedical applications in recent years because of its biocompatibility and biodegradability. In this paper, angle-resolved x-ray photoelectron spectroscopy (ARXPS) was carried out to investigate the chemical groups' spatial orientation on the chitosan membrane surface.…
A series of silica-supported Co−Mo samples prepared by the sol−gel method has been compared as catalysts for the synthesis of single-walled carbon nanotubes (SWNT). The concentration ratio of ammonium hydroxide to the silica precursor tetraethoxysilane (TEOS) has an important effect on the resulting morphology of the…
Abstract A hybrid nonlinear optimal control design is experimentally implemented on a magnetostrictive Terfenol-D actuator to illustrate enhanced tracking control at relatively high speed. The control design employs a homogenized energy model to quantify rate-dependent nonlinear and hysteretic ferromagnetic switching…
We have investigated the ultrafast electric and magnetic response of multiferroic ${\text{GaFeO}}_{3}$ induced by irradiation of a femtosecond laser pulse. By using the polarization selection rules of crystallographic and magnetic second-harmonic generation, the dynamics of electric polarization $P$ and toroidal momen…
High-pressure shear viscosity measurements of polymer/supercritical fluid systems are numerous, but most involve pressure-gradient equipment such as a capillary or slit die with pressure drops exceeding 10%. Pressure change across the measurement region introduces some errors when quantifying the effect of blowing age…
Abstract The bonding characteristics, first hyperpolarizabilities, and origin of the nonlinear optical (NLO) properties of aryloxido and salicylaldehydo derivatives of [XW 5 O 18 ] 3– (X = Zr or Ti) have been investigated using density functional theory (DFT). The flexible bonding behavior of the linkage oxygen (O L )…
${\text{Sr}}_{1\ensuremath{-}x}{\text{Pr}}_{x}{\text{TiO}}_{3}$ has recently been shown to exhibit ferroelectricity at room temperature. In this paper powder x-ray and neutron-diffraction patterns of this system at room temperature have been analyzed to show that the system exhibits cubic (Pm-3m) structure for $x\ensu…
Absorption energies of hydrogen in Mg and Ti as a function of the hydrogen concentration were calculated using density functional theory. We investigated hydrogen absorbed in metal hosts with different structures (fcc, hcp, and bct for Mg; hcp and fcc for Ti). The most stable configurations were determined for differe…
The Zr(0.5-0.5x)Y(0.5+0.25x)Nb(0.25x)O(1.75) solid solution possesses an anion-deficient fluorite structure across the entire 0≤x≤1 range. The relationship between the disorder within the crystalline lattice and the preferred anion diffusion mechanism has been studied as a function of x, using impedance spectroscopy m…
We follow the diffusive motion of colloidal particles of diameter d in soap films of varying thickness h with fluorescence microscopy. Diffusion constants are obtained both from one- and two-particle microrheological measurements of particle motion in these films. These diffusion constants are related to the surface v…
A series of shape memory polyurethane (SMPU) attached by pendant naphthalenes along the polyurethane (PU) chains was prepared. The SMPU chain was composed of 4,4'-methylenebis(phenylisocyanate) (MDI), poly(tetramethyleneglycol)-2000, 1,4-butanediol (BD) as a chain extender, and glycerol. The naphthalene was connected…
Photoinduced intramolecular electron-transfer (ET) and energy-transfer (EnT) processes in two rotaxanes, one containing both zinc porphyrin and C(60) fullerene moieties incorporated around the Cu(I) bisphenanthroline core [(ZnP)(2)-Cu(I)(phen)(2)-C(60)] and a second complex lacking the fullerene [(ZnP)(2)-Cu(I)(phen)(…
Abstract The kinetic behavior of the urethane dimethacrylate (UDMA) copolymerized and reinforced by different concentrations of polyhedral oligomeric silsesquioxane (POSS) with methacrylic groups was studied through Raman spectroscopy. UDMA‐POSS networks have been synthesized with three different types of POSS, two mo…