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31.
The effects of gamma irradiation on crystallization kinetics and microhardness properties of the Li2O–Al2O3–SiO2 (LAS) glass–ceramic sample have been investigated. The glass–ceramic was irradiated to γ-source 60Co of 0.7 MGy. The crystallization kinetics of the irradiated and non-irradiated samples were characterized using differential scanning calorimetry. The crystallization kinetics and microhardness properties of the glass–ceramic changed the gamma irradiation, and the high dose of gamma irradiation affects significantly the crystallization kinetics and microhardness properties of the Li2O–Al2O3–SiO2 glass–ceramic sample.  相似文献   
32.
Apatite type rare earth silicates are being extensively studied as electrolyte material for intermediate temperature solid oxide fuel cells (SOFC). In this paper we presents results on synthesis of Al and/or Fe-doped ATLS, the design of compatible anode materials, thermal expansion properties and co-sintering of half-cells from expansion matched materials using the advanced pulsed electric current sintering (PECS) technique. The issues related to the co-sintering of half cells have been addressed successfully by the combined use of nano powders and PECS.  相似文献   
33.
This work addresses a basic question by Kunen: how many normal measures can there be on the least measurable cardinal? Starting with a measurable cardinal κ of Mitchell order less than two () we define a Prikry type forcing which turns the number of normal measures over κ to any while making κ the first measurable.  相似文献   
34.
A specially designed process for the continuous production of a chiral alcohol by immobilized Rhodotorula glutinis was prepared and is reported. The performance of the process with immobilized cells was also investigated. The run time of the immobilized cells, the flow rates of the substrate, and tris buffer containing 4% glucose in the process were optimized. The immobilized R. glutinis biocatalyst could be used for 15 days with maximum reaction activity. Under the optimized conditions, the continuous production process was operated for 30 days and resulted in 10.8 mL (S)-1-phenylethanol [(S)-1-PE]. The process has been demonstrated on a multigram scale in 75% overall yield with a purity of >99%.  相似文献   
35.
36.
We present a quantitative form of the result of Bai and Yin from [2], and use to show that the section of ℓ 1 (1+δ)n spanned byn random independent sign vectors is with high probability isomorphic to euclidean with isomorphism constant polynomial in δ−1. Partially supported by BSF grant 2002-006. Supported by the National Science Foundation under agreement No. DMS-0111298. Supported in part by the Israel Science Academy.  相似文献   
37.
A survey of redox aminations of indoline with aliphatic ketones using bismuth nitrate as catalyst is described. A reaction of an equivalent amount of indoline and aliphatic cyclic and acyclic ketones provides a mixture of excessive alkylated indole derivatives over typically redox isomerization and reductive alkylation pathways while using of the five equivalent of indoline provides N‐alkylated indolines as a reductive alkylation product. The desired N‐alkyl indoles from the oxidation of N‐alkyl indolines were obtained in excellent yields.  相似文献   
38.
Bi(NO3)3·5H2O‐Catalyzed redox amination scope and mechanistic insights of benzylic ketones with indoline are discussed. The experimental results demonstrate that the formation of N‐alkyl‐substituted indole/indoline derivatives over typically competitive redox and reductive amination processes is depending upon the reaction condition for the benzylic ketones.  相似文献   
39.
A novel route for the synthesis of poly(ethylene glycol)‐b‐polystyrene copolymer, starting from commercially available poly(ethylene glycol) methyl ether and azido terminated polystyrene prepared by atom transfer radical polymerization and subsequent nucleophilic substitution, is applied with simplicity and high efficiency. The combination of photoinduced copper (I)‐catalyzed alkyne‐azide cycloaddition (CuAAC) and ketene chemistry reactions proceeds either simultaneously or sequentially in a one‐pot procedure under near‐visible light irradiation. In both cases, excellent block copolymer formations are achieved, with an average molecular weight of around 7000 g mo1−1 and a polydispersity index of 1.20.

  相似文献   

40.
We compute the homology of random ?ech complexes over a homogeneous Poisson process on the d‐dimensional torus, and show that there are, coarsely, two phase transitions. The first transition is analogous to the Erd?s ‐Rényi phase transition, where the ?ech complex becomes connected. The second transition is where all the other homology groups are computed correctly (almost simultaneously). Our calculations also suggest a finer measurement of scales, where there is a further refinement to this picture and separation between different homology groups. © 2016 Wiley Periodicals, Inc. Random Struct. Alg., 51, 14–51, 2017  相似文献   
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