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31.
Research on Chemical Intermediates - In the current work, an acidic ionic liquid ([{(IMC)-4-OMBH}BIM][HSO4]3) has been utilized as an effective and recyclable catalyst for the synthesis of...  相似文献   
32.
In this paper, we first establish a Schwarz?CPick type theorem for pluriharmonic mappings and then we apply it to discuss the equivalent norms on Lipschitz-type spaces. Finally, we obtain several Landau??s and Bloch??s type theorems for pluriharmonic mappings.  相似文献   
33.
-Eucryptite solid solution (LAS) Li2O : Al 2O3 : 3SiO2(113) was prepared via a sol-gel route. Complex solutions of lithium or aluminum salts in ethanol/water mixtures were catalysed by inorganic acids (catalyst/alkoxide ratio 0.1). Different ratios of H2SO4 catalyst were also used.TGA showed that the maximum % yield of LAS 113 occurred using H2SO4 catalyst. Above 400°C exothermic peaks occurred in DSC followed by the glass transition. XRD and IR showed a high crystallinity of -eucryptite solid solution using all acids at the 0.1 ratio with the highest crystallinity for the 0.05 H2SO4 ratio. SEM revealed similar grain sizes in spite of higher acid concentrations. XRD data indicated a change to a tetragonal modification with higher catalyst ratio.  相似文献   
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Li X  Kyne RE  Ovaska TV 《Organic letters》2006,8(22):5153-5156
A straightforward approach toward the total synthesis of frondosin C is described. This strategy involves a key one-pot, microwave-assisted 5-exo cyclization-Claisen rearrangement sequence that was used for the expedient assembly of the frondosic C scaffold. Subsequent manipulation of the tetracyclic core allowed the synthesis of an advanced intermediate bearing the characteristic diene moiety in the B ring. [reaction: see text]  相似文献   
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A tagged particle interacting with a finite but unbounded number of particles is considered. Some examples of asymptotic completeness are given which are uniform in the number of particles.  相似文献   
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In this paper we show that each factorization structure on a small category , satisfying certain conditions, yields a presheaf on and a morphism of presheaves . We then give connections, and set up one to one correspondences, between subclasses of the following classes: (a) closure operators on (b) subobjects of (c) morphisms from to (d) weak Lawvere–Tierney topologies (e) weak Grothendieck topologies (f) closure operators on .  相似文献   
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A variety of 1-allenyl-2-propargyl-substituted cyclopentanol derivatives were found to undergo facile intramolecular microwave-assisted [2+2] allenyne cycloaddition reactions to generate tricyclic 5-6-4 ring systems present in the sterpurenes.  相似文献   
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