Publications by authors named "V V Postnikov"

Linear conjugated molecules consisting of benzothiadiazole (BTD) and phenyl rings are highly efficient organic luminophores. Crystals based on these compounds have great potential for use as light-emitting elements, in particular, scintillation detectors. This paper compares the peculiarities of growth, structure, and fluorescent properties of crystals based on 4,7-diphenyl-2,1,3-benzothiadiazole () and its organosilicon derivative 4,7-bis(4-(trimethylsilyl)phenyl) BTD ().

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A new linear luminophore consisting of five conjugated units of oxazole, phenylene and a central benzothiadiazole fragment, 4,7-bis[4-(1,3-oxazol-5-yl)phenyl]-2,1,3-benzothiadiazole, has been synthesized and characterized. Needle-like single-crystal samples up to 10 mm in length were obtained by physical vapor transport. The crystal structure was determined at 95 K and 293 K using single-crystal X-ray diffraction.

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The synthesis, growth from solutions and structure of crystals of a new linear thiophene-phenylene co-oligomer with a central benzothiadiazole fragment with a conjugated core, (TMS-2T-Ph)-BTD, are presented. Single-crystal samples in the form of needles with a length of up to 7 mm were grown and their crystal structure was determined at 85 K and 293 K using single-crystal X-ray diffraction. The conformational differences between the crystal structures are insignificant.

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Thiophene-phenylene co-oligomers (TPCOs) are among the most promising materials for organic light emitting devices. Here we report on record high among TPCO single crystals photoluminescence quantum yield reaching 60%. The solution-grown crystals are stronger luminescent than the vapor-grown ones, in contrast to a common believe that the vapor-processed organic electronic materials show the highest performance.

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Objective: The aim of this study was to examine to what extent findings on ultrasonography performed in the emergency department (ED) after hours confirm or alter the referral diagnosis in patients without trauma as reflected in the discharge diagnosis.

Methods: In this prospective study, data from 136 ultrasonographic examinations performed in patients without trauma after hours in the ED during January and February 2002 were evaluated against the suspected preimaging diagnosis of the referring ED physician and the actual discharge diagnosis from the ED or after hospitalization. The rate of preimaging and postimaging concordance was statistically analyzed and compared by calculation of confidence intervals and by the McNemar test.

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