Materials Literature
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The electrochemical behavior of poly(ferrocenyldimethylsilane-b-dimethylsiloxane) (PFDMS-b-PDMS) films deposited on a glassy carbon electrode was investigated by means of cyclic voltammetry (CV). The influences of the solvent, film thickness, temperature, and PDMS block length in PFDMS-b-PDMS on the electrode process…
Gold porphyrins are often used as electron-accepting chromophores in donor-acceptor complexes for the study of photoinduced electron transfer, and they can also be involved in triplet-triplet energy-transfer interactions with other chromophores. Since the lowest excited singlet state is very short-lived (240 fs), the…
Abstract The fracture behavior of biodegradable fiber–reinforced composites as a function of fiber content under different loading conditions was investigated. Composites with different fiber content, ranging from 5 to 20 wt%, were prepared using commercial starch‐based polymer and short sisal fibers. Quasistatic frac…
Surface-enhanced Raman spectra of a single Fe-protoporphyrin IX molecule display drastic fluctuations in frequency and intensity. When analyzed in their temporal evolution, the vibrational modes of the molecule undergo an on-off switching behavior that is shown to follow a Lévy statistics. Such a time dependent proces…
Abstract A series of water‐soluble N‐substituted poly(alkylanilines) (PNAAs) have been enzymatically synthesized with a variety of groups, from methyl to n‐butyl, such as poly( N ‐methylaniline), poly( N ‐ethylaniline), poly( N ‐butylaniline) and poly( N ‐phenylethanolamine). The syntheses were made in the presence of…
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Abstract The crystal structure of γ -P 4 , one of three modifications hitherto reported on white phosphorus, was determined from X-ray powder diffraction data collected at T = 123 K on a Guinier-Simon camera equipped with a cold gas blower and an image plate detector. Crystallographic data at T = 123 K are: space grou…
Direct, in-fluid observation of the surface morphology and nanomechanical properties of the mixed brushes composed of Y-shaped binary molecules PS-PAA revealed nanoscale network-like surface topography formed by coexisting stretched soluble PAA arms and collapsed insoluble PS chains in water. Placement of Y-shaped bru…
Oxygen (nonstoichiometry) re‐equilibration kinetics was examined, via a conductivity relaxation method, on 1 m/o donor (La)‐doped BaTiO 3 (nominal composition, Ba 0.99 La 0.01 Ti 0.9975 O 3 ) against oxygen partial pressure in the range of −16<log ( P O2 / atm)≤ 0 at 1200°C. The kinetics has been found to be onefol…
Reaction of the complex [{CpMo(CO)2}2(mu,eta2-P2)] (1) with CuI halides leads to the quantitative formation of the novel one-dimensional linear polymers [CuX{Cp2Mo2(CO)4(mu,eta2:eta1:eta1-P2)}](infinity) (X=Cl (4), Br (5), I (6)). The same products 4 and 5 were obtained when 1 was treated with CuCl2 and CuBr2, respect…
Abstract Powder samples of β -Ni(OH) 2 and doped variants of the α -Ni(OH) 2 structure type were prepared by a coprecipitation method. Chemical composition was analysed by ICP. Samples were measured by X-ray powder diffraction (XRD). Single peak profiles were analysed by fitting a splitted Pearson VII funktion to the…
Abstract Synthesis and properties of sulfur‐containing linear polythioesters derived from bis(4,4′‐mercaptophenyl)sulfide (MPS) and various acid dichlorides (AC) have been studied to evaluate the effect of the thioester group in comparison with corresponding linear polyesters. Polycondensations between MPS and azelaoy…
The hardness of nanocomposite (nc) films developed recently appears to reach the hardness of diamond. High hardness is commonly attributed to the granular structure of nanocomposites (Hall–Petch effect) [E. O. Hall, Proc. Phys. Soc. Lond. B 64, 747 (1951); N. J. Petch, J. Iron Steel Inst. 174, 25 (1953)]. However, gra…
Abstract Alkali metal decahydro- closo -decaborates M 2 [B 10 H 10 ] (M = Na, Rb, Cs) were synthesised by ion-exchange and characterised via infrared and 11 B-NMR spectroscopy. The crystal structures of Na 2 [B 10 H 10 ], K 2 [B 10 H 10 ], and Rb 2 [B 10 H 10 ] were determined from X-ray powder diffraction data using…
Abstract Regioregular poly(3‐octylthiophene)s were synthesized through a palladium‐catalyzed Suzuki polycondensation of 2‐(5‐iodo‐4‐octyl‐2‐thienyl)‐4,4,5,5‐tetramethyl‐1,3,2‐dioxaborolane. The effects of the palladium catalyst {tetrakis(triphenylphosphine)palladium(0) [Pd(PPh 3 ) 4 ], palladium(II) acetate [Pd(OAc) 2…
Human porphobilinogen synthase (PBGS) can exist in two dramatically different quaternary structure isoforms, which have been proposed to be in dynamic equilibrium. The quaternary structure isoforms of PBGS result from two alternative conformations of the monomer; one monomer structure assembles into a high activity oc…
Abstract Film grade ethylene vinyl acetate (EVA), low density polyethylene (LDPE), and high density polyethylene (HDPE) were melt compounded with an organically modified montmorillonite, then blown into films. The morphology studies showed that all three types of film involve intercalated clay particles. The dependenc…
Abstract The use of hydroxyl‐functionalized hyperbranched polymers (HBPs) (Boltorn ® H20, H30 and H40) was investigated with respect to a UV‐cured epoxy system. Their presence induced an increase of the final epoxy conversion, which was interpreted on the basis of a chain‐transfer reaction. A decrease of the T g value…
Two types of intercalated and exfoliated silicate platelets were allowed to disperse in phenol-cured epoxy matrixes. The different dispersing forms of these silicate platelets in the composites may alter their hardness, transparency, thermal stability, and coefficient of thermal expansion (CTE). In particular, the pre…
Local structure of NaCl-type crystalline Ge2Sb2Te5 has been studied by the atomic pair distribution function analysis of pulsed neutron powder diffraction data. We have found the large displacement of germanium atoms in this crystalline phase. Usually, such a large lattice distortion has disadvantages for the electric…