Materials Literature
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The electrical resistivity, magnetization, and magnetoresistance effect have been studied on a series of Zn-doped polycrystalline samples Fe1−xZnxCr2S4 (0⩽x⩽1) with a spinel structure over a wide range of composition and temperature. It is found that the magnetism and magnetoresistance ratio are anomalous, which do no…
The atomic structure of the {111} diamond face after oxygen--water-vapor etching is determined using x-ray scattering. We find that a single dangling bond diamond {111} surface model, terminated by a full monolayer of $---\mathrm{OH}$ fits our data best. To explain the measurements it is necessary to add an ordered wa…
The plume generated by a pulsed XeCl laser from a novel nanostructured YBaCuO target (n target) is investigated by methods of optical emission spectroscopy and atomic force microscopy. While the spectral positions of the emission lines are the same, stronger line intensities, pertinent to higher kinetic energy of the…
A simple model of charge ordering is considered. It is explicitly shown that at any deviation from half-filling (n ≠1/2), the system is unstable with respect to the phase separation into the charge ordered regions with n =1/2 and the metallic regions with a smaller electron or hole density. A possible structure of thi…
A recombinant strain of Salmonella enterica serovar Typhimurium (mutant in propionate-activation activity) was metabolically engineered to control the composition of poly(3-hydroxybutyrate-co-3-hydroxy- valerate) (PHBV), a polyhydroxyalkanoate copolymer with commercially desirable properties. A gene (prpE) encoding pr…
Two polycrystalline samples of CoFe 2 O 4 were prepared by slow cooling and quenching and studied using Mössbauer spectroscopy and X-ray diffraction. The crystals were found to have a cubic spinel structure with the lattice constants of the slowly cooled sample being a 0 =8.381 Å and the quenched sample being a 0 =8.3…
Stern–Gerlach magnetic deflection measurements were performed on Nin and NinCO (n=8–18) in a molecular beam experiment. Adsorbed carbon monoxide was found to reduce the magnetic moments of most nickel clusters in this size range. For Ni8, the reduction was ∼5 bohr magnetons, while smaller reductions were observed for…
The complexes (E)- and (Z)-Fe(η5-C5H4CHO)(η5-C5H4CH=CH−C6H4-4-NO2) [2-(E) and 2-(Z), respectively], (E)- and (Z)-Fe(η5-C5H4CHO)(η5-C5H4CH=CH−C6H4-4-CN) [3-(E) and 3-(Z), respectively], (E,E)-, (E,Z)-, and (Z,Z)-Fe(η5-C5H4CH=CHC6H4-4-NO2)2 [4-(E,E), 4-(E,Z), and 4-(Z,Z), respectively], (E,E)-, (E,Z)-, and (Z,Z)-Fe(η5-C…
The mechanical quality factor of Pb(Mg1/3Nb2/3)O3–PbTiO3(PMN–PT) and Pb(Sc1/2Nb1/2)O3–PbTiO3(PSN–PT) ceramics have been investigated for compositions close to the morphotropic phase boundary. Investigations were performed for various types of lower valent substituents on the B-site cation. These investigations have sh…
We propose using the anisotropic molecule dope method for synthesizing a zero-birefringence polymer that showed no orientational birefringence at any orientation degree of polymer chains. In this method a rodlike molecule with polarizability anisotropy was chosen to compensate orientational birefringence. The zero-bir…
Epitaxial crystallization of syndiotactic polypropylene (sPP) on 2-quinoxalinol (2-Quin) yields, in the lower part of the crystallization range, the less common and metastable form II based on the packing of isochiral helices, rather than the stable antichiral form I. The contact plane is (110) II . Form II exits only…
Neutral homo- and heterobinuclear complexes with the general formula [(tmtacn)MA(salox)3MB] where MA (MnIII or FeIII) is facially coordinated to the cyclic amine 1,4,7-trimethyl-1,4,7-triazacyclononane (tmtacn) and MB (MnIII or FeIII) is coordinated to the azomethine nitrogens and phenolate oxygens of the bridging lig…
Wetting dynamics on machined wood surfaces is of great interest for the adhesive bonding technology of wood. In this work, the change of apparent contact angles with time of phenolresorcinol-formaldehyde (PRF), polyvinyl-acetate (PVAc), and a series of probe liquids on sawed, planed, sanded, and razor-blade-cut wood s…
The long service life, often in harsh environmental conditions, and the stringent requirements of lightweight design make surface modification an essential part of materials technology for aerospace applications. Six contemporary developments are described, which are representative of advances in corrosion protection,…
Ten copolymers of ethylene and norbornene, synthesised by a metallocene catalyst, covering the composition range from 31 to 62 mol-% of norbornene, have been studied by stress-strain, microhardness and dynamic mechanical measurements. These copolymers show a single glass transition and the correlation between Tg and t…
Ethylene and butadiene are copolymerized with neodymocene catalysts. In this paper, a complete 1 H and 13 C NMR analysis of ethylene/butadiene copolymers is reported for the first time. The results of this study show that the microstructure of copolymers depends on the cyclopentadienyl ligands of the catalyst. The pre…
Deamination of cytosine to uracil and 5-methylcytosine to thymine represents a major mutagenic threat particularly at high temperatures. In double-stranded DNA, these spontaneous hydrolytic reactions give rise to G.U and G.T mispairs, respectively, that must be restored to G.C pairs prior to the next round of DNA repl…
Templates for helix-structured silica microtubulesare generated by subjecting worm-shaped micelles of cetyltrimethylammonium bromide to so-called Taylor vortex flow conditions between a rotating and a stationary cylinder at controlled speed. Silica deposition from TEOS and template dissolution produce helical tubules…
A two‐step ion‐exchange process that introduces strengthening and multiple cracking into glasses has been developed. The experimental parameters in the second step must be carefully controlled to avoid spontaneous cracking, because the compressive stress is reduced in the surface region. Control of the near‐surface st…
Sexual reproduction is commonly assumed to occur in the vast majority of diatoms due to the intimate association of this process with cell size control. Surprisingly, however, little is known about the impact of sexual events on diatom population dynamics. The Sig1 gene is strongly upregulated during sexual reproducti…