Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
The mechanism of material removal of {001} diamond surfaces etched in a flow of 10% oxygen in argon at atmospheric pressure has been studied using ex situ and in situ differential interference contrast microscopy, atomic force microscopy and scanning electron microscopy. It is shown that shallow, square etch pits are…
Abstract Selected hydrazides and thiosemicarbazides of fatty acids with 11, 12, and 18 carbon atoms were synthesized and evaluated as corrosion inhibitors on mild steel and oil‐well steel (N‐80) in boiling 15% hydrochloric acid solution, by weight loss method. Potentiodynamic polarization studies carried out on mild s…
FePO4 is a quartz analogue that presents also an α−β phase transition from a P622 to a P32 phase. We describe in this paper the works done in view of obtaining single crystals, and discuss results showing that an incommensurate phase takes place in between α and β phases in a range of 17 C. The main α−β transition app…
International audience
The resistivity, magnetoresistance, and thermoelectric power (TEP) of ${R}_{1.4}({\mathrm{Sr}}_{1\ensuremath{-}y}{\mathrm{Ca}}_{y}{)}_{1.6}{\mathrm{Mn}}_{2}{\mathrm{O}}_{7}$ and $R({\mathrm{Sr}}_{1\ensuremath{-}y}{\mathrm{Ca}}_{y}{)}_{2}{\mathrm{Mn}}_{2}{\mathrm{O}}_{7}(R=\mathrm{L}\mathrm{a},\mathrm{}\mathrm{E}\mathr…
To identify hepatoprotective agents from plant sources we use primary cultures of rat hepatocytes injured by CCl4. The hepatoprotective agents are the compounds that mitigate the injury caused by CCl4. Using this system we have investigated the biochemical mechanisms involved in the hepatoprotective activity of cynand…
The optical properties of the heavy‐metal oxide glasses 70PbO . 30TiO 2 ,70PbO . 30CdO, and 70PbO . 30TeO 2 doped with Pr 3+ ,Nd 3+ ,and Eu 3+ ions have been investigated. The transition energies of the absorption spectra of Pr 3+ and Nd 3+ ions are analyzed for the Racah parameters, configuration interaction terms, a…
The kinetics of curing for a modified bismaleimide (BMI) has been investigated to ascertain a suitable cure model for the material. The experimental data for characterizing the curing kinetics for a modified bismaleimide resin were determined using a DSC isothermal scan method and indicated a curing mechanism involvin…
Mineralogical, chemical, and isotopic characteristics of clays from Ocean Drilling Program (ODP) sites 1035, 856, 1036, and 858, drilled in Middle Valley at the northern end of the Juan de Fuca Ridge during Legs 139 and 169, were studied using X-ray powder diffraction, differential thermal analysis, infrared spectrosc…
Medium-chain-length (mcl) poly(3-hydroxyalkanoates) (PHAs) are storage polymers that are produced from various substrates and accumulate in Pseudomonas strains belonging to rRNA homology group I. In experiments aimed at increasing PHA production in Pseudomonas strains, we generated an mcl PHA-overproducing mutant of P…
D-Glucose and 19 glucose derivatives were investigated by positive and negative ion matrix assisted laser desorption/ionization time-of-flight mass spectrometry using 2,5-dihydroxybenzoic acid (DHB) as the matrix. The set of substrates includes oligomers of amylose and cellulose, native alpha-, beta-, and gamma-cyclod…
A systematic study of the structural, magnetic and electrical properties of the manganites Pr1-x Sr x MnO3(0≤ x ≤ 0.5) has been carried out. X-ray diffraction investigation shows a structural change with composition, from orthorhombic (0 ≤ x ≤ 0.2) to rhombohedral (0.25 ≤ x ≤ 0.5). The magnetic properties of Pr1-x Sr…
We have performed a theoretical study of the atomic and electronic structure of the four compounds Sr2TiO4, Sr3Ti2O7, Sr4Ti3O10 and SrTiO3, by a total energy semiempirical Hartree-Fock method. We show that the intercalation of SrO3 layers in the perovskite structure of SrTiO3 induces lattice distortions modifications…
Porous microspheres of polyester–polyether block copolymer based on polycaprolactone/polylactide/poly(ethylene oxide) (PCEL) were prepared by an emulsification–solvent evaporation technique. The effect of hydrophilicity/hydrophobicity of the polymer on the morphology of the PCEL microspheres was studied and compared w…
The electro-optic and dielectric properties of organic–inorganic 2-amino-5-nitropyridium dihydrogen phosphate crystals were measured near room temperature at a wavelength of 632.8 nm and as a function of an electric-field frequency that varied from 1 kHz to 40 MHz. The frequency dispersion of the electro-optic coeffic…
We consider a general Fibonacci quasicrystal (FQC) in which both the masses and the elastic constants are aperiodically arranged. Making use of a suitable decimation scheme, inspired by real-space renormalization-group concepts, we obtain closed analytical expressions for the global transfer matrix and transmission co…
We report dc magnetization, M\"ossbauer spectroscopy, and x-ray-diffraction measurements on ${\mathrm{Fe}}_{1\ensuremath{-}x}{\mathrm{V}}_{x}$ alloys, quenched or heat treated, with single phase bcc structure in the whole concetration range. It is well known that the saturation magnetization of these alloys decreases…
The atomic structure of iron phosphate glasses containing uranium has been studied by complementary neutron and x-ray scattering techniques. By combining x-ray and neutron structure factors, detailed information about different pair interactions has been obtained. Most of the basic structural features such as coordina…
Titanium porphyrin hydrazido complexes (TTP)Ti = NNR2 (TTP = meso-tetra-p-tolylporphyrinato dianion; R = Me (1), Ph (2)) were synthesized by treatment of (TTP)TiCl2 with 1,1-disubstituted hydrazines H2NNR2 (R = Me, Ph) in the presence of piperdine. The nucleophilic character of the hydrazido moiety was demonstrated in…
Thin films of poly(vinylcinnamate) and poly(7-methacryloyloxycoumarin) have been exposed to linearly polarized UV light. The resulting anisotropic films have been characterized by using UV, conventional and polarization modulation FTIR spectroscopies. In particular, several internal vibrational modes have been used as…