Materials Literature
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We have synthesized and characterized the following four metalloporphyrins: Fe(OEP)(CO)(1-MeIm), Ru(OEP)(CO)(1-MeIm), Os(OEP)(CO)(1-MeIm), and Fe(TPP)(iPrNC)(1-MeIm), where OEP = 2,3,7,8,12,13,17,18-octaethylporphyrinate, TPP = 5,10,15,20-tetraphenylporphyrinate, and 1-MeIm = 1-methylimidazole, using single-crystal X-…
Inelastic x-ray measurements of polybutadiene are reported, performed over a wide temperature range covering both the glass and the liquid phase. At each temperature, the frequency position $\ensuremath{\Omega}$ and the width $\ensuremath{\Gamma}$ of the inelastic peaks of the spectra have been obtained for different…
Summary To examine the role of reactive oxygen species (ROS) in the signal transduction that leads to hypersensitive cell death, we used a previously established system in which a xylanase from Trichoderma viride (TvX) induces an oxidative burst and cell death in a culture of tobacco cells. Diphenylene iodonium and N‐…
A classical relaxor material, PbMg1/3Nb2/3O3 (PMN), has a long history of investigations by Raman and Brillouin spectroscopies. Earlier results on Raman scattering have emphasized a predominant role of disorder and, on the whole, confirmed a model of compositional fluctuations, first suggested by Smolensky and his col…
Anions PF6− and CF3SO3− are trapped by the new radical host [(Cu-dppe)3{hat-(CN)6}]2+, which was synthesized in a one-pot reaction from a copper(I) source, hat-(CN)6, and dppe in acetone. The trapped salts have been characterized both in solution and in the solid state (see picture: A−: PF6−, CF3SO3−). hat-(CN)6=hexaa…
Alkane dehydrogenation catalyzed by the Ir(III) complexes (PCP‘)Ir(H) 2 ( 1 ) [PCP‘ = η 3 -C 6 H 3 (CH 2 PH 2 ) 2 -1,3] and CpIr(PH 3 )(H) + ( 10 ) [Cp = η 5 -C 5 H 5 ] is investigated with density functional theory (DFT). For both systems the theoretical results show that catalytic alkane dehydrogenation to alkene pr…
Macromolecular impurities present in solution have profound effects on the growth and quality of protein crystals used for x-ray structure determinations. We have imaged the three-dimensional distribution of ovotransferrin impurities in crystals of the protein hen egg white lysozyme (HEWL) using two-photon excitation…
Activation of Cdc2-cyclin B (or M phase-promoting factor (MPF)) at the prophase/metaphase transition proceeds in two steps: dephosphorylation of Cdc2 and phosphorylation of cyclin B. We here investigated the regulation of cyclin B phosphorylation using the starfish oocyte model. Cyclin B phosphorylation is not require…
We report here, the first observation of features such as the Olympic Rings on transmission electron micrographs of amorphous BaFe 12 O 19 nanoparticles prepared by a sonochemical decomposition technique. The barium hexaferrite was formed as a colloidal solution without the use of a surfactant. Rings of smaller dimens…
BspA is a basic surface-exposed protein from Lactobacillus fermentum BR11. Sequence comparisons have shown that it is a member of family III of the solute binding proteins. It is 89% identical to the collagen binding protein, Cnb, from Lactobacillus reuteri. Compared with the database of Escherichia coli proteins, Bsp…
Change of electronic and lattice structures upon the orbital and charge-ordering (OO-CO) transition has been investigated for a single-layer manganite crystal of ${\mathrm{La}}_{1/2}{\mathrm{Sr}}_{3/2}{\mathrm{MnO}}_{4}.$ The optical birefringence signal probes the orbital-ordering-induced anisotropy in the originally…
An electromigration model is developed to simulate the reliability of Al and Al–Cu interconnects. A polynomial expression for the free energy of solution by Murray [Int. Met. Rev. 30, 211 (1985)] was used to calculate the chemical potential for Al and Cu while the diffusivities were defined based on a Cu-trapping mode…
The oil resistance behavior of polystyrene thermoplastic vulcanizates (TPVs) such as polypropylene (PP)/polystyrene block copolymer (SBC) systems were investigated using a dynamic mechanical spectrometer (DMS) and transmission electron microscopy (TEM). Testing oils used were paraffinic oil, ASTM oil #3, an automobile…
The (001) surface of natural pure margarite was chemically characterized by angle-resolved Xray photoelectron spectroscopy (ARXPS). The extreme surface sensitivity of ARXPS permits concluding that the chemical composition of the near-surface region differs from the bulk because of the strong anisotropy of the margarit…
We report x-ray photoemission spectra for a CaCO3 filled poly(vinyl chloride) (PVC) polymer with dioctyl pthalate plasticizer. XPS spectra were acquired with a SSI model SSX-100 instrument using monochromated Al Kα x-rays. We present the survey spectrum (binding energy 0–1000 eV) and a narrow spectrum of the C 1s, O 1…
We report x-ray photoemission spectra for a poly(propylene)(PP) homopolymer. XPS spectra were acquired with a SSI model SSX-100 instrument using monochromated Al Kα x-rays. We present the survey spectrum (binding energy 0–1000 eV) and a narrow spectrum of the C 1s photoelectron peak.
Adverse effects from the usage of plasticisers and diluents in the manufacture of flexible poly(vinyl chloride) (PVC) products have recently received increased environmental concern. As a consequence there is a lot of work in progress to find more environmentally friendly systems and/or systems that can reduce the con…
Formation of lead niobate pyrochlores by the reaction of PbO with Nb 2 O 5 in various molar ratios and at various temperatures has been investigated. It has been shown that for a PbO/Nb 2 O 5 molar ratio between 1.5 and 3.0, a pyrochlore solid solution having cubic symmetry is formed at low temperatures (∼500‐600°C).…
Abstract This paper presents a short overview of the background to EP additives and their operating mechanism in relation to temperature activation, in the formulation of water‐miscible metal working fluids. The physical and chemical properties, determined using standard laboratory equipment, and dynamic tests, of dif…
A theory of the central peak line shape in Raman scattering in ferroelectrics above ${T}_{c}$ is developed. Off-center ions are considered as a possible source of the local symmetry breaking. We argue that in order to properly describe the features of the central peak line shape above ${T}_{c}$ one should take into ac…