New layered perovskites, KSr2Nb3O10 and two new protonated niobates HSr2 Nb3O10·1.2H2O and HSr2Nb3O10,were synthesized by solid state reaction and ion-exchange reaction. These new compounds -were characterized by...
详细信息
New layered perovskites, KSr2Nb3O10 and two new protonated niobates HSr2 Nb3O10·1.2H2O and HSr2Nb3O10,were synthesized by solid state reaction and ion-exchange reaction. These new compounds -were characterized by EPMA, AAS, XRD, IR, DTA and so on. The structure may be described as treble perovskite sheets [Sr2Nb3O10]- interleaved with K+ ,H3O + or H+. These new compounds are new members of the Dion-Jacob-sonseries with n=3 for the general formula M[An-1 NbnO3n+1], and their indexed X-ray powder diffraction data were first reported in the paper.
b Department of Chemistry, Wuhan University, Wuhan, Hubei 430072, China The action of β ( N selenomorpholine) ethyl phenyl ketone hydrochloride and 4 ( N selenomorpholine) 2 butanone hydro chl...
详细信息
b Department of Chemistry, Wuhan University, Wuhan, Hubei 430072, China The action of β ( N selenomorpholine) ethyl phenyl ketone hydrochloride and 4 ( N selenomorpholine) 2 butanone hydro chloride on Escherichia coli and Staphylococcus aureus was studied by microcalorimetry. Differences in their capacities to affect the metabolism of this bacterium were observed. The kinetics shows that the selenomorpholine compounds had action on the metabolism process of Escherichia coli and Staphylococcus aureus. The rate constant ( k ) of the studied bacterium in the presence of the drugs are concentration dependant. The growth rate constants decrease with an increase in the mass of the selenomorpholine compounds, but their relationship is different. As deduced from the rate constant ( k ) of the studied bacterium (in log phase) and the half inhibitory concentration (IC 50 ), the experimental results reveal that the studied selenomorpholine compounds all have good antibiotic activity and better antibacterial activity on Staphylococcus aureus than on Escherichia coli.
The solid solutions of Al2(1.x)MgxTi 1+xO5 (x=0,0.01,0.05,0.1) were fabricated by the solid phase reaction method, and they were sintered under normal pressure. The thermal performance of Al2(1-x)MgxTi1+xO 5 was mainl...
详细信息
The solid solutions of Al2(1.x)MgxTi 1+xO5 (x=0,0.01,0.05,0.1) were fabricated by the solid phase reaction method, and they were sintered under normal pressure. The thermal performance of Al2(1-x)MgxTi1+xO 5 was mainly investigated. The results show that, the additive MgTi2O5 can not only restrain the decomposition of Al 2TiO5, but also greatly improve the densification of the solid solutions. With increasing mole percent of x, the thermal stability of Al2(1-x)MgxTi1+xO5 increases and the expansion coefficient decreases.
In contrast to the commonly used arc melting method, samples in the present paper were prepared by the solid-state reaction from element powders at 1173K under a flowing argon atmosphere for 4-7 days. The constituent ...
详细信息
In contrast to the commonly used arc melting method, samples in the present paper were prepared by the solid-state reaction from element powders at 1173K under a flowing argon atmosphere for 4-7 days. The constituent phases and the element compositions were determined and showing that samples were of single phase and stoichiometric. ZrNiSn powder was then consolidated by using the spark plasma sintering technique. The effect of sintering temperature and holding time on the density was discussed. It is found that, dense ZrNiSn compounds with fine grain size and homogeneous microstructure were achieved under the condition of 1123K-40MPa-25min.
Millimeter wave processing of materials is a method which has wide application prospect for improving material characteristics. In this paper, the investigated results of millimeter wave processing of materials in IEC...
详细信息
ISBN:
(纸本)0780374231
Millimeter wave processing of materials is a method which has wide application prospect for improving material characteristics. In this paper, the investigated results of millimeter wave processing of materials in IECAS, such as millimeter wave sintering of Al/sub 2/O/sub 3/, ZnO, Nd/sub 2/Ti/sub 3/O/sub 9/, and chemical syntheses of spinels LiMn/sub 2/O/sub 4/ and LiCo/sub 0.1/Mn/sub 1.99/O/sub 3.92/S/sub 0.08/, as cathode materials of Li-ion batteries, with millimeter wave heating are presented.
A kind of W/W-Mo/Mo system layered flier-plate material (LFP) was fabricated in this study by the methods of powder metallurgy and bonding together. Such LFP had high parallelism,planeness and densification and its de...
详细信息
A kind of W/W-Mo/Mo system layered flier-plate material (LFP) was fabricated in this study by the methods of powder metallurgy and bonding together. Such LFP had high parallelism,planeness and densification and its density varied from 17.25x103 kg/m3 to 10.22x103 kg/m3 through a total thickness of 3.0 mm. The W-Mo interlayer of this LFP was obtained by hot-press sintering and its densification at 1573 K was studied. Then by using additives 4Ni-3Cu (in wt pct), the LFP was fabricated under 1573 K-30 MPa-60 min. The mechanism of the interfacial bonding of the W/W-Mo/Mo system LFP was also mainly investigated.
Al/Al2O3 composites of different ratios were hot-press sintered at 575～640℃ under a pressure of 30 MPa for 2 h in a vacuum furnace. It was found that the relative density of the Al/Al2O3composites could be increased...
详细信息
Al/Al2O3 composites of different ratios were hot-press sintered at 575～640℃ under a pressure of 30 MPa for 2 h in a vacuum furnace. It was found that the relative density of the Al/Al2O3composites could be increased evidently with the rise of sinter temperature. No reaction occurred between Al and Al2O3 at the sinter temperatures. Under 640℃-30 MPa-2 h experimental condition, Al/Al2O3 system FGM was successfully fabricated, and its density range changed quasi-continuously from 2.887x103 kg/m3 to 3.1909x103 kg/m3 within the middle 1.0 mmthickness range.
(PEO)xMoO3·nH2O(x=0～2) nanocomposite films were prepared by ion exchange method and polymer solution direct intercalation in sol-gel route. The synthesis and structure of the films were investigated by XRD, DSC,...
详细信息
(PEO)xMoO3·nH2O(x=0～2) nanocomposite films were prepared by ion exchange method and polymer solution direct intercalation in sol-gel route. The synthesis and structure of the films were investigated by XRD, DSC, FTIR, etc. The results show that MoO3 xerogel has a layered structure, which arranges in b-direction. The interlayer distance of MoO3 xerogel increases from 0.690 nm at x=0 to 1.308 nm at x=2 after heat treatment. PEO can be completely intercalated into the interlayer at x=0.5～1 and has strong interaction with MoO3 host.
The dislocation structure in magnetron sputtered c-textured YBCO films deposited on (100)SrTiO3 substrates consists of vertical (//c axis) screw dislocation forests together with layered horizontal (|caxis) edge dislo...
详细信息
The dislocation structure in magnetron sputtered c-textured YBCO films deposited on (100)SrTiO3 substrates consists of vertical (//c axis) screw dislocation forests together with layered horizontal (|caxis) edge dislocation net-works. It is found that in the oxygenation process in YBCO films, oxygen diffusion is enhanced greatly by the short circuit paths which we suggest to be the horizontally ( c axis) layered edge dislocation net-works. Diffusion equation for oxygenation was solved with the help of Fishers theory of grain boundary diffusion, and an active energy 1.16 ev.``
Filled skutterudite NaFe/sub 4/P/sub 12/ single crystal nanowires were synthesized by using a hydrothermal-reduction-alloying method. X-ray diffraction (XRD), Electron diffraction (ED), Raman scattering, as well as el...
详细信息
Filled skutterudite NaFe/sub 4/P/sub 12/ single crystal nanowires were synthesized by using a hydrothermal-reduction-alloying method. X-ray diffraction (XRD), Electron diffraction (ED), Raman scattering, as well as elemental analysis were used to characterize the product. High-resolution transmission electron microscope (HRTEM) was used to investigate the microstructure of the nanowire. A growth mechanism of NaFe/sub 4/P/sub 12/ nanowire was proposed.
暂无评论