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In this work, seven copolymers possessing thienothiophene and mesitylboron units were prepared. Incorporation of triphenylamine (TPA) and tetraphenylethene (TPE) into TT unit was probed to enhance their light-emitting efficiencies. Density functional theory investigations of the model compounds revealed the presence of an intramolecular charge transfer transition between the donor TT units and the boron acceptor atom. Among the seven TT-boron copolymers, four of them were used for the fabrication of polymer light emitting diodes 9PLEDs) and two of the devices exhibited pure white color according to the CIE. Although the efficiencies of the devices are low, as this study is the first example of thienothiophene inverted perpendicular inverted perpendicular-boron copolymers emitting white color, they are promising examples for future studies.

Synthesis of comonomer, possessing 4,4'-dinonyl-2,2'-bithiazole and 3,5-diphenyldithieno[3,2-b;2',3'-d] thiophene (T-NBT-Ph2DTT-NBT-T) units, was achieved using Stille cross coupling reaction. Its electropolymerization was conducted in acetonitrile, containing 0.1 M NaCLO4 + 0.1 M LiCIO4 (MCIO4). Properties of the polymer film, obtained P[T-NBT-Ph2DTT-NBT-T], were characterized by electrochemical techniques. Effect of the polymerization charge on the redox behavior of the polymer film was investigated, and the film was further characterized by UV-visible spectrophotometric measurements. Corresponding electrical equivalent circuit was applied to the experimental electrochemical impedance spectroscopy (EIS) data to explain the parameters Of each element and the interface of the Pt/P[T-NBT-Ph2DTF-NBT-T]/MCIO4 system. The band gap of the polymer was obtained as 1.86 eV by in situ spectroelectrochemical measurements. Good stability in the oxidized state was verified experimentally. Molecular orbitals and electropolymerization of the comonomer were investigated at OFT level. (C) 2016 Elsevier Ltd. All rights reserved.

Two novel D-A (donor-acceptor) and one D-A-D small molecules containing mesitylborane as an acceptor and triphenylamine as a donor, linked through a thieno[3,2-b]thiophene p-conjugated spacer, are synthesized and characterized. Their photo- and electrochemical properties were investigated by experimental and computational studies. The emission quantum efficiencies were determined to be between 46% and 68% in THF. Their solid-state quantum yields were recorded up to 42%. The fabricated electroluminescent devices as emitting materials showed sky-blue to yellowish green emissions. Their devices exhibit high performance with a turn-on voltage, maximal brightness, and highest luminescence efficiency of up to 4.0 V, 1200 cd m(-2) and 1.13 cd A(-1), respectively. These results pave new avenues for the future molecules possessing D and A units connected via fused thiophenes.

Synthesis of comonomer possessing 4,4'-dinonyl-2,2'-bithiazole and 3-phenylthieno[3,2-b] thiophene units (PhTT-NBT-PhTT) was performed under Stille cross coupling condition. Its electropolymerization was conducted in the presence of trifluroborate-diethyl ether (BF3 center dot DEE) to lower the electrochemical polymerization potential through a complex formation between heteroaromatic monomers and boron trifluoride. Electrochemical properties of obtained P[PhTT] and P[PhTT-NBT-PhTT] films, such as effect of electrolyte, polymerization charge, potential limits on the redox behaviour were investigated. They were further characterized by UV-visible spectrophotometric measurements. Corresponding electrical equivalent circuit was applied to the experimental electrochemical impedance spectroscopy (EIS) data to explain the parameters of each element and the interface between the Pt/P[PhTT]/BF3 center dot DEE and Pt/P[PhTT-NBT-PhTT]/BF3 center dot DEE systems. The band gap of P[PhTT-NBT-PhTT was obtained as 2.04 eV by insitu spectroelectrochemical measurements. Frontier molecular orbitals and electropolymerization of the comonomer were assessed computationally. (C) 2016 Elsevier Ltd. All rights reserved.

The disproportionately low presence of marine species in the list of invasive alien species (IAS) of Union concern of the European Union (EU) Regulation 1143/2014 does not fully acknowledge the threat they pose to the EU marine environment. In this study, the first EU-scale Horizon Scanning (HS) focusing on marine alien species was performed, aiming to deliver a ranked list of species that should be of high priority for risk assessment (Article 5 of the EU IAS Regulation). Species absent from or with a limited distribution in EU marine waters were targeted. In total, 363 alien species were initially screened for HS by a panel of experts, including a broad range of taxonomic groups. Species were scored for their likelihood of arrival, establishment, spread, and impact in EU waters. A consensus workshop ranked 267 species, including a subset of 26 prioritized species. These species are considered to be mainly introduced by shipping (fouling and ballast water), via the Suez Canal, and aquaculture activities. The 26 priority species were also scrutinized in terms of feasibility of their management; 18 of them were suggested for performing risk assessments on the basis of the EU IAS Regulation. Since biological invasions are dynamic and connected with accelerated globalization and diversified human activities, we recommend HS to be repeated periodically to review the species already listed and assess new ones.

The present paper deals with the description of specimens of a new species of Pseudobranchiomma Jones, 1962 collected from the Sea of Marmara between 50 and 100 m depths, a genus that, up to now, is represented within the Mediterranean area by only one species. The new species is mainly characterized by having radioles without serrations, well-developed paired compound eyes on radioles, absence of dorsal pinnular appendages, minute interramal eyespots appearing after chaetiger 5, and pointed ventral sacs and lappets. The morphological features of the new species are compared to those of the most similar species.