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361.
Reaction of the stable digermyne BbtGeGeBbt (Bbt = 2,6-[CH(SiMe3)2]2-4-[C(SiMe3)3]-C6H2) with ethylene initially afforded the corresponding 1,2-digermacyclobutene. Depending on the reaction conditions applied, further reaction of this 1,2-digermacyclobutene with ethylene furnished two different reaction products: a 1,4-digermabicyclo[2.2.0]hexane or a bis(germiranyl)ethane. Combined experimental and theoretical results suggested that the 1,4-digermabicyclo[2.2.0]hexane and the bis(germiranyl)ethane are the thermodynamic and kinetic reaction products, respectively. A reaction mechanism in agreement with these results was proposed.  相似文献   
362.
Two‐dimensional (2D) coordination polymers (CPs) have a highly accessible surface area that permits guest molecules to effectively access the micropores in the CPs. Here we report a bottom‐up synthesis of 2D cyano‐bridged Cu–Pt CP nanoflakes using trisodium citrate as a chelating agent, which controls the nucleation rate and the crystal growth. The lateral sizes of the CP nanoflakes are controlled by changing the amount of trisodium citrate used. We strongly believe that our method will be useful for the preparation of other types of 2D CP nanoflakes. The 2D CPs have many active sites for catalytic and electrochemical reactions, and furthermore the assembled CPs can be used as membrane filters.  相似文献   
363.
Treatment of 2,5‐di(3,5‐tert‐butylphenyl)‐1‐lithioferrocene with GeCl2?dioxane afforded the corresponding chlorogermylenoid that exhibited an ambident reactivity in different solvents; it displayed a behavior characteristic for a dichlorogermylene anion in THF, while it exhibited the typical reactivity of a chlorogermylene in toluene. X‐Ray diffraction analysis of a single crystal of this chlorogermylenoid, obtained from recrystallization in THF, revealed a separated‐ion‐pair structure in the solid state.  相似文献   
364.
The signal-to-noise ratio (SNR) in the photochromic super-resolution readout of optical disks was theoretically analyzed. The shot noise limited SNR, such as that in magnetooptical disks, was improved only for the short recorded mark. However, the media noise limited SNR, such as that in phase change disks, was greatly improved for both short and long recorded marks.  相似文献   
365.
Reactions of a sterically crowded 1,3,2-dithiastannetane derivative bearing 2,4,6-tris[bis(trimethylsilyl)methyl]phenyl (=Tbt) and 2,4,6-triisopropylphenyl (=Tip) groups on the tin atom are described. Both thermolysis and photolysis of the 1,3,2-dithiastannetane [Tbt(Tip)SnS2CPh2] resulted in the formation of products derived from the corresponding stannanethione [Tbt(Tip)Sn=S], while the oxidation reaction by m -chloroperbenzoic acid gave a novel tincontaining heterocyclic system, an 1,2,4,5-oxadithiastannolane derivative.  相似文献   
366.
A linear drop of the interfacial tension between polyamide 6 (PA6) and poly(propylene) (PP) upon increasing concentration of the reactive compatibilizer and a leveling-off at higher compatibilizer contents were found in this study. The reduction of the interfacial tension is compared with the reduction of the dispersed phase size of the corresponding blends. As a result, the domain size is not directly proportional to the interfacial tension under the condition that other factors are equal.  相似文献   
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