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。
We recently designed and produced a family of new swelling-type materials that are potentially capable of self-fixation in bone. These materials are designed to absorb body fluids and swell by small amounts, which will allow the implants made from these materials to achieve self-fixation by an expansion-fit mechanism.…
FTIR spectroscopy of CO adsorbed at liquid-nitrogen temperature on zeolite K-L revealed two main IR absorption bands at 2161 and at 2150 cm -1 , respectively. These bands were assigned to the C–O-stretching mode of carbon monoxide interacting, through the carbon atom, with K + ions present in the main channel of the z…
SummaryIn order to reduce corrosion rates, zinc plated parts are usually chromated. Recently Chromates have caused increasingly environmental concern, for both allergic effects among workers touching chromated parts and toxic effects on fish, plants and bacteria.A molybdate based alternative has been developed to repl…
Our investigation is focused on the understanding of high-field phenomena in polymers. In highly insulating materials such as polyethylene, space charge has a strong influence on both the short and long term breakdown strengths. The aim of this report is to demonstrate and discuss the importance of the dynamics of vol…
A series of ruthenium–copper bimetallic catalysts on silica were prepared by the co-impregnation method. The amount of ruthenium was maintained constant at 1 wt.%. Copper loadings varied from 0.01 to 0.1 wt.%. Catalysts were characterized using surface area measurements (BET), CO adsorption followed by temperature-pro…
The topology of the microstructure and the grain growth kinetics of Nd-Fe-B magnets have been examined after sintering-time intervals between 0.5 and 19 h by metallographic analysis. In dense magnets about 80% of the grains have 5 to 7 corners. The fraction of grains with >8 corners increases with sintering-time and t…
The electronic structures of the µ 4 -chalcogenido silver(I) complexes [Ag 4 (µ-dppm) 4 (µ 4 -E)] [O 3 SCF 3 ] 2 (E = S 1, Se 2 or Te 3; dppm = Ph 2 PCH 2 PPh 2 ) have been calculated by use of the Fenske–Hall molecular orbital method. The results indicate that complexes 1–3 show similar electronic structures, with th…
Dimethyl[2,4-dioxo(1 H,3 H)pyrimido]tetrathiafulvalene (1) and dimethyl-[2-amino-4-oxo(3 H)pyrimido]tetrathiafulvalene (4) form unusual inner salts by oxidation in the presence of bases. The insoluble black-green betaines 2 and 5 react with acids to form cation radical salts. Betaine 2 in the presence of acid and bis-…
Abstract In this work, short carbon fibers were blended with poly(vinyl chloride) (PVC) plastisol forming a conductive network of the fibers in the composite. The effects of concentration and initial length of the carbon fibers on the conductivity of the network were studied. For an initial fiber length of 3 mm (L/D =…
We have identified a novel cardiac steroid, 11,19-epoxy-19-methoxytelocinobufagin, named marinosin (1), in the skin of the toad, Bufo marinus (L.) Schneider. The treatment of compound 1 with 50% CH3CN containing 0.1% trifluoroacetic acid yielded a 11 alpha-hydroxyhellebrigenin (2), which has not previously been isolat…
Organosilicon hydrides are oxidized to the corresponding silanols in high yield in a homogenous phase in the presence of a small amount of water and a catalytic amount of a rhodium complex.
Nanophase SiC/Si3N4 composite powders were synthesized by the carbothermal nitridation of SiO2. These powders have desirable characteristics of high quality with oxygen contents on the order of 1.5 to 2 wt. %, surface area of ∼ 10 m2/g, submicron α-Si3N4, low metallic impurity levels, and a homogeneous distribution of…
New linearly extended π-electron donors based on bridged dithienylethylene (DTE) end-capped with diversely substituted 1,3-dithiol-2-ylidene electron-releasing groups have been synthesized by Wittig–Horner olefination of appropriate aldehydes. Cyclic voltammetry shows that whereas the unbridged analogues are directly…
The reaction of the Group 2 metal hydroxides, oxides or carbonates in 95% ethanol in the presence of a suitable glyme ligand L–L [i.e. Me(OCH 2 CH 2 ) n OMe, n = 3, 4 or 7] and a β-diketone, has yielded either [M(β-diket) 2 (L–L)] or [{M(β-diket) 2 } 2 (L–L)] [M = Mg–Ba; β-diket = Htmhd (2,2,6,6-tetramethylheptane-3,5…
Novel fluoroarylporphyrins bearing electron donor dimethylamino groups in the meso-aryl positions and an electron acceptor nitro group on one of the pyrrole carbons exhibit significant solvent dependent fluorescence spectra and time-resolved emission properties. These effects are suggestive of intramolecular charge tr…
Symmetrically tetrasubstituted metal-free and metal phthalocyanines (M = 2H, Cu, Ni, Co, Zn or Fe) with four 15-membered heteroatom (N, O, S)-containing donor sites attached have been synthesized and characterized by elemental analysis, IR, NMR, UV/VIS spectroscopy and thermogravimetric analysis.
Composite materials reinforced with braided, woven, knit, and stitched fibrous preforms are emerging as potential alternatives to unidirectional prepreg tape. A variety of these material forms are currently being evaluated by major airframe manufacturers.
Abstract The structural properties of alumina as well as its fluoride and sodium modifications were characterized by X‐ray diffraction, infrared spectroscopy and differential thermal analysis. We have shown, that fluoride ions interact with hydroxyls type Ia of γ‐Al 2 O 3 forming Al–F species, which then react at 400…
Luminescence of Eu 3+ and Tb 3+ intercalated in K 2-x H x Ti 2 O 5 layered oxides is observed by exciting the layered titanate host indicating that the energy transfer via electron–hole trapping from the layered host to the guest in the interlayers occurred.
This work evaluates the sorption potential of an hydrotalcite compound [Mg3Al(OH)8]2CO3H2O, HT, and its calcined product Mg3AlO4(OH), HT500, for sodium dodecylbenzenesulfonate, DBS, in water. The results obtained by spectrophotometric measurements show that the adsorption of DBS in HT was low, while in the HT500 the a…