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。
[reaction: see text] A new poly(ethylene glycol)-supported porphyrin has been prepared and its ability as a promoter in photooxidation reactions has been studied. The PEG-supported catalyst exhibits high activity, comparable to that of a nonanchored sensitizer, and it is easily removable by filtration from the reactio…
Structural studies and stability of cluster-like particles of Ru x and Ru x Se y were performed in situ via X-ray diffraction at wide angles (WAXS). Both materials have a similar particle size (1.4−1.6 nm) in the reduced state. Whereas Ru x particles are rather sensitive to oxygen from air, the chemical stabilization,…
An introduction to X-ray Intensity Fluctuation Spectroscopy (XIFS) is given by describing its relationship to speckle from coherent sources. A brief description of the relationship of XIFS measurements to the underlying equations of motion is given. Preliminary results for the charge density wave (CDW) system NbSe 3 a…
The distribution of cations over the positions in the structures of labuntsovite-group minerals was studied by X-ray diffraction analysis and IR spectroscopy. Several types of cation order over the five key positions are established depending on cation composition and their force characteristics.
Abstract The B–Co system is investigated via thermodynamic modeling and experiments. In the modeling section, all of the experimental phase diagram and thermodynamic data available from the literature were critically reviewed and assessed by using thermodynamic models for the Gibbs energies of individual phases. In th…
β‐Bi 2 O 3 compositions were prepared to evaluate the effect on properties of using mixed dopants. Baseline compositions containing 28 mol% of the alkaline‐earth oxides CaO, SrO, or BaO were used for comparison. When the alkaline earths were combined in pairs to dope the bismuth oxide, the resulting properties were in…
AgI nanoparticles with zincblende structure are promising materials for laser based optical communication systems and therefore deserve to be optimally synthesized. We have explored ambient iodization as a strategy for controlled AgI nanoparticle growth on (a) mesoporous Ag foils, (b) Ag-Cu quasi-amorphous thin films…
A layered double-hydroxide intercalation compound was synthesized to measure the uniaxial stress the host layers exert on the intercalants. To measure the uniaxial stress, we employed the photoluminescence (PL) from the intercalated species, the Sm ion complex, as it is sensitive to the deformation of the intercalants…
Abstract The coalescence rate in immiscible polymer blends predicted by all existing models is two or three orders of magnitude lower than that observed experimentally. The model developed in this study considers for the first time that coarsening is driven by van der Waals forces and there is slippage at the interfac…
We report here our preliminary results of pliitonium corrosion studied using photoelectron spectroscopy and secondary ion mass spectrometry. Plutonium surfaces were cleaned by Ar ion bombardment, and examined using X-ray and ultraviolet photoelectron spectroscopy, Auger electron spectroscopy and secondary ion mass spe…
It is important to stress that XRD must not be used as a &s;black box&s; to characterize cementitious materials. Ordinary Portland cement (OPC) is not made from pure minerals but from quarries that generally contain substantial amounts of impurities. Thus, the alite component of Portland cement is not pure C^S but is…
Abstract The crystal structure of Cu 4 Bi 4 Se 9 , synthesized at 400 °C, was determined from single crystal X-ray diffraction data and refined to the R 1 value of 0.05. The compound is orthorhombic, with a = 32.692 Å, b = 4.120 Å, and c = 12.202 Å, space group Pnma . The structure contains three square pyramidal Bi s…
This is an electronic version of the revised U.S. Air Force Damage Tolerant Design Handbook. The technical content of the 2002 edition is enhanced by the addition of new developments in the areas of corrosion, widespread fatigue damage, and probabilistic methods. New sample problems are included which illustrate the s…
Fluorescence quantum yields and luminescence spectra for solid samples are presented and interpreted. Re-absorption of the emitted light is very important in these systems causing a decrease in the observed luminescence quantum yield as well as distortions in emission spectra (usually a shift to longer wavelengths). T…
Dislocation motion in short-range-ordered solid solutions under stress are investigated in situ by transmission electron microscopy. For the first time, local reordering created by the back slip of mobile dislocations is proven to exist. Dislocation movement within pile-ups produces local disordering by forward slip d…
The effect of rim structure formation and external restraint pressure on fission gas release at transient conditions has been examined by using an out-of-pile high pressure heating technique for high burnup UO2 fuels (60, 74 and 90 GWd/t), which had been irradiated in test reactors. The latter two fuels bore a develop…
Abstract Blends of 75/25 poly(ethylene terephthalate) (PET)/high density polyethylene (HDPE) containing poly(ethylene‐co‐methacrylic acid) partially neutralized with lithium (PEMA‐Li) were obtained by direct injection molding in an attempt (i) to ameliorate the poor performance of the binary blend and (ii) to find the…
Impedance spectroscopy was used to study the temperature dependence of the resistance and capacitance of niobium‐doped strontium titanate ceramics and also to identify the main contributions determining potential applications. Nyquist plots ( Z ″ versus Z ′) show a main contribution in the intermediate‐frequency range…
We report on the transport characteristics of individual multiwalled carbon nanotube/nanofibers (MWCNTs) grown by plasma-enhanced chemical vapor deposition (PECVD). The measurements were performed on individual MWCNT nanobridges suspended by sputtered Nb contacts. Temperature dependent measurements of conductance reve…
Abstract A reinforced trouser tear test was developed to evaluate the tear resistance of thin ductile films. Tests with blown film of linear low‐density polyethylene blended with up to 30 wt% of a high melt strength polypropylene (hmsPP) demonstrated that the test differentiated among films based on composition and th…