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101.
102.
A convenient laboratory scale preparation of cyanogen has been developed. This new method generates cyanogen from the pyrolysis of diacetyl-glyoxime which can be easily prepared from glyoxime. 相似文献
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We establish a new refinement of the right-hand side of the Hermite–Hadamard inequality for convex functions of several variables defined on simplices. 相似文献
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106.
Alfred Schmidpeter Siegfried Lochschmidt Günther Burget William S. Sheldrick 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):23-26
Abstract Reduction of PCl3 e.g. with trialkyl phosphines produces the well-known but ill-defined insoluble, amorphous, orange material approximating a phosphorus subchloride. In repeating this reduction with Ph3P and with AlCl3 as a third component we now obtained crystalline hexaphenyl triphosphenium tetrachloroaluminate. It may be thought to derive from the four electron cation P+ being complexed by two Ph3P. 相似文献
107.
Satyan Choudhary Alfred J. Crosby 《Journal of polymer science. Part A, Polymer chemistry》2018,56(23):1545-1551
Evaporative self-assembly (ESA), based on the “coffee-ring” effect, is a versatile technique for assembling particle solutions into mesoscale patterns and structures on different substrates. ESA works with a wide variety of organic and inorganic materials, where the solution is a combination of volatile solvent and nonvolatile solute. Modified ESA methods, such as “stop-and-go flow coating,” use a programmed meniscus “stick–slip” motion to create mesoscale assemblies with controlled shape, size, and architecture. However, current methods are not scalable for increased production volumes or patterning large surface areas. We demonstrate a new ESA method, where an oscillating blade controls the meniscus depinning and drives the evaporative assembly of solutes at the pinned meniscus. Results show that oscillation frequency and substrate speed control time/distance intervals between successive meniscus depinning, and the assembly dimensions depend on solution concentration, oscillation frequency, substrate speed, and meniscus height. We report the mechanism of the meniscus depinning and the control over assembly cross-sectional dimensions. This advance provides a scalable ESA method with faster processing times and maintained advantages. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1545–1551 相似文献
108.
Dieter Weber Günther Burget Karl-Heinz Zirzow Hans Georg Von Schnering Alfred Schmidpeter 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4)
Abstract Alkalimetal diphenylphosphinites degrade (Ph-P)5 and P4 to give anions containing a chain of 2, 3 or 4 four- and two-coordinated phosphorus atoms. Representatives of the chain with two four-coordinated and one two-coordinated P atoms became first available from the aminolysis of tris (phosphoryl)phosphides1. 相似文献
109.
Thomas Von Criegern Alfred Schmidpeter 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):305-308
Abstract 2,2′-Dipyridyl ketone 4a, 2-benzoyl pyridine 4b, and pyridine-2-aldehyde 4c coordinate by N and O to the chlorospiro-phosphorane 1, substitute the chloride and give tricycliccations 6 of hexacoordinate phosphorus. Nucleophilic attack of trimethyl phosphite at the carbonyl center and loss of methyl chloride converts them to the neutral sixcoordinate diastereomeric species 7. From the coalescence temperature of their 1H-NMR signals ΔG for the interconversion of the diastereomers is estimated to 18 kcal mol?1. 相似文献
110.
Alfred Schmidpeter Angela Willhalm Jürgen Kroner Roberta O. Day Joan M. Holmes Robert R. Holmes 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):495-498
Abstract Phosphamethincyanines prepared in 1964 by Dimroth and Hoffmann were among the first compounds with two-coordinate phosphorus. They are special cases of 2-phospha-allylic cations. Simple representatives of this type become available from the reaction of imidoyl chlorides with tris(trimethylsily1)phosphane. 相似文献