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。
Phosphate glasses are of technological interest for electrochemical devices, as bioactive materials, and also for the electronic industry. Solid-state NMR, chiefly coupled with magic angle sample spinning (MAS), is a valuable technique to obtain information on short-range order and connectivity in phosphate glasses. I…
The cycloadditions of 3,4-dihydro-2H-pyrrole 1-oxide, 3,4,5,6teuahydropyridine 1-oxide, and (S)-3,4-dihydro-2-hydroxymethyl-2H-pyrrolc 1oxide to a,P-unsaturated acid derivatives have been reviewed.As Z-olefins, several five, six, and seven membered lactones with different functionalization at the y-position were emplo…
It is well known that a cloud cavitation is one of the most destructive forms of cavitation. The set of equations for the motion of a spherical bubble cloud is formulated. Behavior of bubble clouds are simulated numerically when the surrounding pressure is decreased from 50 kPa to a 10 kPa and then increased to 50 kPa…
The majority of knitted fabric composites reported in the literature are based on rigid matrix materials, either thermoset or thermoplastic polymers. This paper describes the fabrication and characterization of a knitted fabric reinforced elastomer composite. The composite was made from a combination of weft knitted p…
Abstract Kaolin (dickite and/or kaolinite) cement occurs locally in the Chalk Group (Upper Cretaceous-Lower Tertiary) in the North Sea and the Derbyhaven Beds (Lower Carboniferous) on the Isle of Man, United Kingdom. Stable-isotope and petrographic data indicate that the kaolin cements in both the Chalk Group and Derb…
Methyl protopyropheophorbides-a/d were prepared by modification of readily available chlorophyll-a. The key step was oxidation of 13 1 -oxo-chlorin to the corresponding porphyrin, and 2,3-dichloro-5,6-dicyano-p-benzoquinone was effective for 17,18-dehydrogenation. A reduction in oxidation potential of the chlorin was…
A soft X-ray beam-position monitor based on a thin CVD diamond photodetector has been developed for use on third-generation synchrotron radiation facilities, and has been tested on beamlines ID26 and ID12 at the European Synchrotron Radiation Facility. Since diamond exhibits a low absorption to low-energy X-ray photon…
As semiconductor devices shrink, the minimum interconnect dimensions become comparable to the mean free path (mfp) of electrons in the interconnect metal. The resistivity of thin films rises above the bulk value around the mfp, due to the dominating effects of surface scattering of electrons. We explored the resistivi…
Three new cobalt porphyrins, two of which are coordinated by a nitrosyl group have been synthesized and characterized by spectral and electrochemical methods. The investigated compounds are represented as (TPPBr4)Co(NO), (TPPBr4NO2)Co and (TPPBr4NO2)Co(NO) where TPPBr4 and TPPBr4NO2 are the dianions of 7,8,17,18-tetra…
The reaction of meso-octaethylporphyrinogen–lanthanide complexes, [{(η5∶η1∶η5∶η1-Et8N4)M}Na(thf)2] [M = Pr, Nd], with NaC10H8 in an ethylene or acetylene atmosphere leads to the isolation of dimeric species, where the metals are bridged by the [C2H4]2– and [C2]2– anions.
We present the results of variable temperature neutron powder diffraction studies of three low thermal expansion materials belonging to the NZP family; K 0.5 Nb 0.5 Ti 1.5 (PO 4 ) 3 , Ba 0.5 Ti 2 (PO 4 ) 3 and Ca 0.25 Sr 0.25 Zr 2 (PO 4 ) 3 . Each of these structures has half occupancy of the crystallographic site for…
Polycaprolactone/poly(ethylene oxide)/polylactide tri-component copolymers (PCEL) with different compositions were synthesized by copolymerization of epsilon-caprolactone and L-lactide in the presence of poly(ethylene glycol) using stannous octoate as a catalyst. The copolymers were purified and characterized by vario…
Rheological properties of cellulose fibrous suspensions were measured with a cone-plate type rheometer. Effect of particle concentrations, c, and salt concentrations of the systems on the properties were studied. The flow curve of the fully dialyzed system showed Newtonian flow at a particle concentration of 0.1 wt%.…
The effect of a magnetic field on the formation of structural domains at martensitic transition in the intermetallic system Ni/sub 2+x/Mn/sub 1-x/Ga was studied. For the compositions x whose temperatures of structural and magnetic transitions are close this effect is most pronounced. In the field of 0.2 to 1 T the inc…
Because retinyl palmitate was reported to be more stable to oxidation than retinol, we wondered if retinyl palmitate was also more resistant to photolysis as compared to free alcohol. We investigated the resistance of ethanolic solutions of retinol, retinyl palmitate, or both to air oxidation and (or) photolysis using…
Abstract The oriented association of two or more polytypes of the same compound enters neither in the Friedel's definition of twinning nor in that of epitaxy/syntaxy; for it the term allotwinning is here introduced and the relevant laws of formation are established. The appearance of allotwins is in principle recogniz…
The ferroelastic symmetry changes of the lead-based complex perovskite PbFeY 0.5 Ta 0.5 O 3 are investigated by means of single crystal x-ray diffraction and observations in polarized light microscopy at different temperatures. The position of the 400 and 222 cubic reflections is followed between 80 K and 300 K. Resul…
CeVO 4 prepared via the sol‐gel route with a tetragonal ( I 4 1 / amd ) crystal structure was found to act as an ion‐storage material. The structure of powders and films having different Ce / V molar ratios was determined using X‐ray diffractometry. Cyclic voltammograms of films allowed for distinguishing between the…
Raman spectra of molten ThCl4–ACl (A = Li, Na, K or Cs) mixtures have been measured. The complete composition range has been studied for all systems at temperatures up to 960 °C. The spectral changes upon melting the binary compounds A2ThCl6, A3ThCl7 and the pure crystalline ThCl4 were also measured. The data indicate…
This article examines the effects of dispersed phase concentration, processing apparatus, viscosity ratio, and interfacial compatibilization using an SAN–amine compatibilizer on the morphology of blends of bisphenol A–polycarbonate (PC) with styrene–acrylonitrile (SAN) copolymers. For uncompatibilized blends, the disp…