Materials Literature
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Nonlinear optical dendritic macromolecules, called azobenzene dendrons, were synthesized, and their conformational properties and molecular nonlinear optical properties were clarified by second-order nonlinear optical measurement. The synthesized molecules were modified by introducing 1−15 numbers of azobenzene branch…
Nanocrystals of ZnO have been produced by an alkoxide based synthesis involving diethylzinc, tert -butyl alcohol, ethanol, and water. The resulting ZnO is in the form of a powder made up of zincite crystallites in the size range of 3−5 nm. These crystallites aggregate together to form larger spherical particles. These…
A bulk polycrystalline sample of YBa_(2)Cu_(3)O_(7-δ) (δ\approx 0.1) has been irradiated by γ-rays with ^{60}Co source. Non-monotonic behavior of T_{c} with increasing irradiation dose Φ(up to 220 MR) is observed: T_{c} decreases at low doses (Φ< 50 MR) from initial value (\approx 93 K) by about 2 K and then rises, fo…
Stability constants are reported for the coordination of pyridine and substituted pyridines to the alkylcobalt(III) complexes of octaethylporphyrin (OEP), t-octaethylchlorin (OEC), and ttt-octaethylisobacteriochlorin (OEiBC) in toluene solution. The stability constants correlate with the base strength of the nitrogeno…
The present study examines the relationship between thermal conductivity and planarity in polyimide films. The samples tested were specially prepared to range in orientation from three dimensionally random to highly planar. The molecular structure and orientation of the polyimide film have been characterized by polari…
Electrical resistivities, absorption spectra, and X-ray diffraction of one-dimensional bis(dimethylglyoximato)platinum(II), Pt(dmg) 2, have been studied in detail at high pressures. The resistivity drastically decreases with increasing pressure and reaches the minimum at around 6.5 GPa and then slowly increases with i…
{[oPONit]MnCl(μ-Cl)}2 is a di-chloro-bridged Mn(II) binuclear compound in which each Mn(II) is coordinated by (o-nitronyl nitroxide-phenyl)diphenylphosphine oxide acting as a bidentate ligand via the oxygen atoms of the PO and N−O groups. The spectrum of the low-lying states has been deduced from the magnetic and EPR…
In the present study, a dynamic model is developed for the calculation of the molecular weight and long chain branching distributions in a continuous solution metallocene-catalyzed ethylene polymerization reactor. The model is based on the fractionation of the total polymer chain population into a number of classes, e…
Sr- and Mg-doped LaGaO 3 powders with various dopant concentrations (La 1 - x Sr x Ga 1 - y Mg y O 3 - ( x + y )/2 where 0.02 ≤ x ≤ 0.2 and 0.02 ≤ y ≤ 0.2) were synthesized through a novel solution combustion route. X-ray diffraction patterns indicate orthorhombic structure for compositions 0 ≤ x ≤ 0.075 and 0 ≤ y ≤ 0…
To study the freezing/melting behavior of a confined N 2, CO, and Kr, we performed X-ray diffraction measurements of N 2, CO, and Kr confined inside the cylindrical pores of five kinds of siliceous MCM-41 with different pore radii ( R = 1.45−2.9 nm) as a function of temperature. Freezing and melting of these three mol…
Different sizes of Fréchet-type dendrons with a thiol group at the focal point were synthesized, well characterized, and used as building blocks for the preparation of self-assembled monolayers (SAMs) on metal surfaces. From the studies of the kinetic process of dendron thiol self-assembling on gold, it is shown that…
Nanocrystalline barium hexaaluminate has been successfully synthesized through the use of a reverse microemulsion as a medium for controlled hydrolysis and polycondensation of barium and aluminum alkoxides. The nanoparticles derived were characterized with electron microscopy, X-ray diffraction, and nitrogen adsorptio…
Synchrotron radiation X-ray powder diffraction data (SPDD) have been obtained for Ag[AgF4]2, Au[AuF4]2, Ag[AuF4], and Ag[AuF6]. Ag[AgF4]2 and Au[AuF4]2 are isostructural with Ag[AuF4]2, space group (SG) P2(1)/n, Z = 2, with the following: for Ag[AgF4]2 a = 5.04664(8), b = 11.0542(2), c = 5.44914(9) A, beta = 97.170(2)…
A series of ionic 4-amino-1-methylpyridinium benzenesulfonate salts have been prepared by quaternization reaction of 4-aminopyridine with methyl benzenesulfonates having a substituent of hydroxy, methoxy, methyl, chloro, or bromo group at para position. The X-ray structure analysis has been performed for their single…
Unusual single N-bridging thiocyanato and double pyridazine (pdz) bridges occur in the linear trinuclear nickel(II) complex of formula [Ni3(pdz)6(NCS)6]. The compound exhibits a quasi Curie law behavior, the antiferromagnetic coupling through the double 1,2-diazine links being nearly compensated by the ferromagnetic e…
Poly(vinylidene fluoride) (PVF 2 ) produces thermoreversible gels in diesters. By variation of the number of intermittent carbon atoms ( n = 0−7) of the diesters, the physical properties of the gels are studied. The morphology of the PVF 2 /diethyl oxalate (DEO) gel is spheroidal, but the morphology of PVF 2 −diethyl…
Dielectric behavior was examined for solutions of a styrene-isoprene-styrene (SIIS) triblock and SI diblock copolymers in an I-selective solvent, n -tetradecane (C14). The SI copolymer had noninverted type-A dipoles in the I block while the SIIS copolymer, a head-to-head coupled dimer of SI, had once-inverted dipoles…
Polarized X-ray absorption spectroscopy has been used to study the short-range structure of deposited films of V2O5 xerogel. The material is characterized by a layer of VO5 units with the V-O apical bond perpendicular to the basal (xy) plane. We have focused our attention along the z axis. Experiments were carried out…
This Account focuses on fundamental aspects and applications of the concept of "electron and proton reservoirs". Permethylated electron reservoir iron sandwich complexes, which were known to be excellent reducing agents in their neutral 19e Fe(I) form, have recently been shown to be stable strong oxidants in their dic…
We present a complete study of the Multiparticle Biased Diffusion-Limited Aggregation (MBDLA) model supplemented with surface difussion (SD), focusing on the relevance and effects of the latter transport mechanism. By comparing different algorithms, we show that MBDLA+SD is a very good qualitative model for electrodep…