634 research outputs found
Control over the Self-Assembly Modes of Pt<sup>II</sup> Complexes by Alkyl Chain Variation: From Slipped to Parallel π-Stacks
We report the self-assembly of a new family of hydrophobic, bis(pyridyl) PtII complexes featuring an extended oligophenyleneethynylene-derived π-surface appended with six long (dodecyloxy (2)) or short (methoxy (3)) side groups. Complex 2, containing dodecyloxy chains, forms fibrous assemblies with a slipped arrangement of the monomer units (dPt⋯Pt≈14 Å) in both nonpolar solvents and the solid state. Dispersion-corrected PM6 calculations suggest that this organization is driven by cooperative π-π, C-H⋯Cl and π-Pt interactions, which is supported by EXAFS and 2D NMR spectroscopic analysis. In contrast, nearly parallel π-stacks (dPt⋯Pt≈4.4 Å) stabilized by multiple π-π and C-H⋯Cl contacts are obtained in the crystalline state for 3 lacking long side chains, as shown by X-ray analysis and PM6 calculations. Our results reveal not only the key role of alkyl chain length in controlling self-assembly modes but also show the relevance of Pt-bound chlorine ligands as new supramolecular synthons. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Мобильное приложение для онлайн продажи билетов на основе мессенджера Telegram
Объектом исследования является деятельность ООО "Меридиан" по онлайн продаже билетов в кинотеатры. Цель работы – проектирование мобильного приложения для онлайн продажи билетов на основе мессенджера Telegram. В процессе исследования была изучена специфика онлайн продаж с помощью мобильных приложений, был проведен теоретический анализ, обзор аналогов, проектирование и разработка мобильного приложения, анализ проявлений вредных и опасных факторов. В результате разработано мобильное приложение, реализующее основные функции: учет продажи билетов; информирование клиентов; анализ продаж и взаимосвязей с клиентами. Область применения: онлайн продажа билетов.The object of study is the activity of LLC "Meridian" in online sales of movie tickets. Purpose – to design mobile applications for online sale of tickets on the basis of the messenger Telegram. In the process of the study examined the specificity of online sales via mobile applications was the theoretical analysis, a review of analogues, the design and development of mobile applications, analysis of the manifestations of harmful and dangerous factors. The developed mobile application that implements the basic functions: accounting for the sale of tickets; informing customers; analysis of sales and relationship with customers. Scope: the online sale of tickets
Self-sorted photoconductive xerogels
We show that a perylene bisimide (PBI)-based gelator forms self-sorted mixtures with a stilbene-based gelator. To form the self-sorted gels, we use a slow pH change induced by the hydrolysis of glucono-δ-lactone (GdL) to gluconic acid. We prove that self-sorting occurs using NMR spectroscopy, UV-Vis spectroscopy, rheology, and viscometry. The corresponding xerogels are photoconductive. Importantly, the wavelength dependence of the photoconductive films is different to that of the films formed from the perylene bisimide alone. Transient absorption spectroscopy of the xerogels reveals changes in the spectrum of the PBI on the picosecond timescale in the presence of stilbene with a PBI radical anion being formed within 10 ps when the stilbene is present. The ability to form the PBI radical anion under visible light leads to the enhanced spectral response of the multicomponent gels. These systems therefore have potential as useful visible-active optoelectronics
Direct oxidative arylation via rhodium-catalyzed C–C bond cleavage of secondary alcohols with arylsilanes
Extrusion of CO from Aryl Ketones: Rhodium(I)-Catalyzed CC Bond Cleavage Directed by a Pyridine Group
Scope and Mechanistic Investigations on the Solvent-Controlled Regio- and Stereoselective Formation of Enol Esters from the Ruthenium-Catalyzed Coupling Reaction of Terminal Alkynes and Carboxylic Acids
Excited-State Dynamics of Hybrid Multichromophoric Systems: Toward an Excitation Wavelength Control of the Charge Separation Pathways
Synthesis and Characterization of Long Perylenediimide Polymer Fibers: From Bulk to the Single-Molecule Level
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