Search results for "Ologen"

Electron Accumulative Molecules.

2018

With the goal to produce molecules with high electron accepting capacity and low reorganization energy upon gaining one or more electrons, a synthesis procedure leading to the formation of a B–N(aromatic) bond in a cluster has been developed. The research was focused on the development of a molecular structure able to accept and release a specific number of electrons without decomposing or change in its structural arrangement. The synthetic procedure consists of a parallel decomposition reaction to generate a reactive electrophile and a synthesis reaction to generate the B–N(aromatic) bond. This procedure has paved the way to produce the metallacarboranylviologen [M(C2B9H11)(C2B9H10)-NC5H4-…

A robust viologen and Mn-based porous coordination polymer with two types of Lewis acid sites providing high affinity for H 2 O, CO 2 and NH 3

2017

A novel porous coordination polymer [Mn(pc3)(H2O)2]·xH2O (3 < x < 4) is synthesized in water at pH = 7 using the anionic viologen-carboxylate ligand 4,4′-bipyridinium,1,1′-bis-(2,4-dicarboxyphenyl) (pc32−). Dehydration of the material results in the formation of open pores containing two types of accessible Lewis acid sites: exposed Mn2+ cations and N+ atoms of viologen units. Due to this property the PCP shows high affinity and capacity in the adsorption of H2O, CO2 and NH3. Despite the presence of strong adsorption sites this material is stable in liquid water and in gaseous NH3.

Drosophila Evolution over Space and Time (DEST) - A New Population Genomics Resource

2021

Abstract Drosophila melanogaster is a leading model in population genetics and genomics, and a growing number of whole-genome datasets from natural populations of this species have been published over the last 20 years. A major challenge is the integration of these disparate datasets, often generated using different sequencing technologies and bioinformatic pipelines, which hampers our ability to address questions about the evolution and population structure of this species. Here we address these issues by developing a bioinformatics pipeline that maps pooled sequencing (Pool-Seq) reads from D. melanogaster to a hologenome consisting of fly and symbiont genomes and estimates allele frequenc…

Ionic liquid crystals based on viologen dimers: tuning the mesomorphism by varying the conformational freedom of the ionic layer

2016

ABSTRACTWe investigated the liquid crystal behaviour of newly synthesised bistriflimide salts of symmetric viologen dimers. A smectic A phase was observed for intermediate spacer lengths and for relatively long lateral alkyl chains. The systems were characterised by thermal analysis, polarised optical microscopy, X-ray scattering and solid-state NMR. An intermediate ordered smectic phase was also exhibited by the compounds (except for systems with very short lateral chains) consisting of molten layers of alkyl chains and partially ordered ionic layers. These results, relating to the mesomorphic behaviour of viologen salts, are qualitatively compared to those of the more common imidazolium s…

Solubilization control by redox-switching of polysoaps

2008

Reversible changes in the self-organization of polysoaps may be induced by controlling their charge numbers via covalently bound redox moieties. This is illustrated with two viologen polysoaps, which in response to an electrochemical stimulus, change their solubility and aggregation in water, leading from homogeneously dissolved and aggregated molecules to collapsed ones and vice verse. Using the electrochemical quartz crystal microbalance (EQCM), it could be shown that the reversibility of this process is better than 95% in 16 cycles.

Thermal behaviour and electrochemical properties of bis(trifluoromethanesulfonyl)amide and dodecatungstosilicate viologen dimers

2012

We report the synthesis and characterization of dimeric viologen salts (1',1''-(alkane-1,n-diyl)bis(1-ethyl-4,4'-bipyridinium) with n = 4-10) with bis(trifluoromethanesulfonyl)amide (bistriflimide, Tf(2)N(-)) as a counteranion. For n = 4, 5 and 6, and for the nonylviologen cation (1,1'-dinonyl-4,4'-bipyridinium) we also prepared salts with the totally inorganic dodecatungstosilicate anion, SiW(12)O(40)(4-), featuring a poly-charged surface and nanosized dimensions. The materials have been characterized by means of calorimetric techniques, X-ray diffraction and solid state NMR and a comparison is made with analogous monomeric viologen salts exhibiting smectic mesophases. A strong odd-even ef…

Probing DNA conductivity with photoinduced electron transfer and scanning tunneling microscopy.

2012

Abstract The possibility that the stacked DNA bases can mediate vectorial electron transfer has been examined using two different approaches. Experiments on photoinduced electron transfer with intercalated donors and acceptors (either randomly bound or linked dyads of ruthenium complex and viologen) indicate that while DNA may be a better medium than acetonitrile for electron transfer over short distances (2-3-base pair, equivalent to 10-14Å centre-to-centre separation), it is a poor medium for transport over larger separations. Attempts to measure conductivity of individual DNA molecules using scanning tunneling microscopy to image mixed monolayers of mercaptohexanol (MCH) and 30-mer or 10…

Photoinduced DNA damage efficiency and cytotoxicity of novel viologen linked pyrene conjugates.

2010

Novel viologen linked pyrene conjugates permeate cells efficiently and exhibit spacer length dependent DNA damage and cytotoxicity upon photoexcitation.

Sicurezza ed Efficacia dell’ Inserto Ologen™ Nella Chirurgia Del Glaucoma: Risultati Di Uno Studio Prospettico Di Fase II.

2009

Flexible vs Rigid Networks of Two Isoreticular Viologen-Carboxylate based PCPs: the Ligand Size Effect

2018

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