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161.
Al- and Co-substituted lithium nickel oxide of the nominal composition Li(Ni0.75Al0.17Co0.08)O2 was synthesised by a coprecipitation technique and by several solid state routes. Rietveld analysis of XRD profiles and galvanostatic
cycling in glass cells were performed for structural and electrochemical characterisation. Depending on the reactivity of
the respective precursor, there is in each case a minimal synthesis temperature, at which a single phase of the R
layered structure could be obtained. The coprecipitation technique and solid state routes using pre-substituted nickel hydroxide
are suitable for the synthesis of single phase Al- and Co-substituted lithium nickel oxide, even at rather low synthesis temperatures.
The electrochemical performance of lithium nickel oxide Li(Ni0.75Al0.17Co0.08)O2 synthesised in air is poor due to an enhanced lithium nickel disorder. Synthesis in oxygen atmosphere seems to be required.
Paper presented at the 6th Euroconference on Solid State Ionics, Cetraro, Calabria, Italy, Sept. 12–19, 1999. 相似文献
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163.
Steven Arnold 《Journal of multivariate analysis》1984,15(3):325-335
Fairly general sufficient conditions are given to guarantee that invariant tests about means in the multivariate linear model and the repeated measures model have the correct asymptotic size when the normal assumption under which the tests are derived is relaxed. These conditions are the same as Huber's condition which guarantees asymptotic validity of the size of the F-test for the univariate linear model. 相似文献
164.
The interaction between morphological structure and phase behaviour of a LC side group block copolymer has been investigated using DSC, TEM and small angle X-ray diffraction. All samples of Polystyrene-block-2-(3-cholesteryloxycarbonyloxy)ethyl methacrylate (PS-b-PChEMA) show a phase separation between the two blocks. It was found that in the case of those samples where the liquid crystalline sub-phase is not continuous (spheres), only a nematic phase is seen, whereas in all samples in which there is a continuous liquid crystalline sub-phase, the smectic A phase of the homopolymer is formed. On the other hand, the block copolymer seems to stabilize the LC phase; no dependency of the clearing temperatures on the molecular weight of the LC blocks has been observed. 相似文献
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B. Luk'yanchuk N. Bityurin N. Arnold D. Bäuerle 《Applied Physics A: Materials Science & Processing》1996,62(5):397-401
The role of non-stationary effects in nano-second ultraviolet (UV) excimer-laser ablation of organic polymers is discussed. The model includes reversible changes in absorption related to darkening and bleaching effects. Comparison of calculations and experimental data for polyimide demonstrates that the photophysical model describes the ablation kinetics quite well. 相似文献
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An optimal control problem for a single bulk-service queue is considered. Theorems that characterize the optimal control strategy in some circumstances are proved; they complement earlier results by Deb and Serfozo for a comparable problem. Most of the analysis uses direct probabilistic reasoning rather than specialized methods such as dynamic programming. Some illustrative examples are presented. 相似文献