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 reactions between hexamethylenetetramine (HMTA) and compounds which model novolac resins have been studied by 13C- and 15N-NMR techniques. The dimer and tetramer compounds vary in molecular size and structure and react with HMTA to yield benzylamines and benzoxazine as the major initial-formed intermediates and co…
O crescente interesse em ampliar a previsibilidade dos fenômenos que ocorrem durante a fabricação de materiais cerâmicos por processos coloidais, como a variação da viscosidade de suspensões, tem estimulado a implantação de vários modelos teóricos com tal finalidade. Considerando a concentração de sólidos na suspensão…
Thin films of SrBi2Ta2O9 (SBT) were deposited on Si using Sol-Gel technique. The thicknesses of the films 200 nm (SBT2) and 400 nm (SBT4), respectively. SEM were studies showed most of the grains in the film are smaller than 0.1 μ. FTIR reflectivity measurements of the samples showed bands around 1260, 936(for SBT2),…
This paper presents experimental data on the bonding of CO and NO to vacuum-cleaved MgO(100) and NiO(100) and compares them with theoretical results. In the case of CO and NO on NiO(100) we find that the bonding energies obtained for the vacuum-cleaved single crystals agree well with results of recent studies on thin…
In EXAFS analysis of Rb-doped silicate glasses and of cetyltrimethylammonium bromide (CTAB) adsorbed on carbon black, the spline approximation of the atomic background is inadequate. Instead, a residuum obtained from absorption spectra of Rb and Br ions in aqueous solution after removal of the structural signal is use…
A bleomycin-binding protein, designated BLMT, encoded on the transposon Tn5 was crystallized using the vapour-diffusion method in a form suitable for X-ray diffraction analysis. Crystals were grown at pH 6.5 in 0.1 M sodium cacodylate and 0.2 M calcium acetate, using 25% PEG 6000 as a precipitant. They belong to the o…
Abstract The high-temperature γ -phase of lithium sodium carbonate ( γ -LiNaCO 3 , a = 8.311 Å, c = 3.386 Å, P [unk]) has been studied by X-ray diffraction and computer simulation methods. The results of computer simulation based on the ionic model and the temperature dependence of the superlattice reflection intensit…
A new method to measure the effective charge density responsible for the enhanced particle capture of electret filters is reported. The experimental method relies on the use of ionizing radiation from a Po210 radioactive source combined with measurements of the penetration of particles of known size and charge through…
In the present work, the positive-definite conditions of the elastic constants of two-dimensional (2D) quasicrystals with non-crystallographic symmetries have been derived. These results are necessary for studying elastic and mechanical properties of two-dimensional quasicrystals both in theory and in experiment. Proj…
The point defect structure of a doped oxide, (Mg~_xFex)~.80, was quantitatively determined by in situ high temperature X-ray absorption spectroscopy (1270 K<T<1470 K). Spectra were recorded under defined oxygen activity at the dopanrs K-edge. The degree of oxidation o~ versus T, ao, and x can be consistently described…
Abstract The structure of a compound previously described as Bi 8 Se 9 Cl 6 has been determined and refined to R = 0.040. It is very similar – if not identical – to the structure of a compound described as Bi 11 Se 12 Cl 9 . In contrast to the latter, it accounts for a weak fourfold superstructure and therefore differ…
The ability of digital PD analyzers to process and store specific information concerning discharge activity can be used for various purposes: discharge recognition and condition monitoring. To exploit these possibilities, a specific fingerprint technique has been successfully used in recent years for off-line and on-l…
The fracture characteristics of high‐strength steel ASTM A‐490 under a hydrogen environment were investigated, with special emphasis placed on changes in fracture characteristics due to a tempering treatment at temperatures from 200 to 400 °C. A mechanical test was performed on cathodically charged specimens subjected…
By determining sound pressure using the Ramann-Nath parameter and confirming sound form based on schlieren images, we investigated the effects of ultrasound frequency on the sonochemical luminescence of a luminol solution. Separating the effect into the luminescence threshold of sound energy and the rate of luminescen…
A method for measuring magnetization under high pressure and pulsed high magnetic field was developed for a Drickamer-type cell using diamond anvils and an insulator gasket. As the first test, the magnetization of invar alloy Fe0.65Ni0.35 was measured at room temperature up to 8 GPa in a pulsed field of 10 T with a wi…
The avoidance model introduced by Han and Herzfeld [Mater. Res. Soc. Symp. Proc. 463, 135 (1997)] for parallel, charged spherocylinders is extended to the case of charged spherocylinders with orientational freedom. The accuracy of the theory in the dilute solution limit is checked by comparing the predicted second vir…
Abstract Engine oils today include detergency dispersancy additives to keep the engine clean, hold insolubles in dispersion, and neutralise acidic compounds. This paper describes the synthesis of a type of detergent‐dispersant based on polyisobutenyl succinimides. The type and route of synthesis influence the molecula…
To reveal the interaction of persistent slip bands (PSBs) with grain boundaries (GBs), a specially designed [134]/[18 2 7]copper bicrystal with a tilting GB and a common primary slip plane in its component crystals was prepared. The dislocation patterns within grains and near the GB in the copper bicrystal cyclically…
In this tutorial review magnetostrictive effects useful for sensors and actuators are described and compared with piezoelectric effects. Magnetostrictive materials are surveyed in the context of sensor and actuator applications.
Out paper describes the general principles behind the fabrication of graded composites produced through powder stacking techniques. Both metal and ceramic systems are addressed. The complex interdependence of many processing variables makes production of graded composites challenging. Variables include relative green…