Smartphones and other mobile devices have fundamentally changed patterns of Internet use in everyday life by making online access constantly available. The present paper offers a theoretical explication and empirical assessment of the concept of online vigilance, referring to users’ permanent cognitive orientation towards online content and communication as well as their disposition to exploit these options constantly. Based on four studies, a validated and reliable self-report measure of online vigilance was developed. In combination, the results suggest that the Online Vigilance Scale (OVS) shows a stable factor structure in various contexts and user populations and provides future work in communication, psychology, and other social sciences with a new measure of the individual cognitive orientation towards ubiquitous online communication.

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Blubber and liver samples from six striped dolphins (Stenella coeruleoalba) found dead in the Mediterranean sea in 1989-1990 were tested for 37 coplanar and chiral polychlorinated biphenyls (PCBs), including the enantiomeric ratios of 9 chiral PCBs. The method includes a fractionation step using HPLC (PYE column) for separating the PCBs according to the number of chlorine atoms in the ortho positions. HRGC/ECD and HRGC/LRMS with an achiral column (DB-5) were used to determine the PCB congeners. The enantiomeric ratios of nine chiral PCBs were determined by HRGC/LRMS (SIM) with a chiral column (Chirasil-Dex) and by MDGC as the confirmatory technique. The total PCB concentration (sum of 37 congeners) ranged from 7.2 to 89.6 µg/g (wet weight) and from 0.52 to 29.2 µg/g (wet weight) for blubber and liver samples, respectively. PCB profiles were dominated by congeners 138, 153, 170, and 180. The toxic equivalent values (TEQ) ranged from 0.17 to 3.93 ng/g (wet weight) and from 0.02 to 0.73 ng/g (wet weight) for blubber and liver samples, respectively. PCBs 95, 132, 135, 149, and 176 revealed an enantiomeric excess of the second eluted enantiomer in almost all of the samples, whereas PCBs 136 and 174 were racemic or almost racemic. PCBs 88 and 91 were under the detection limits of the methodology used.

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A series of polycondensed aromatic N‐heterocycles (acridine, benzo‐f‐quinoline 1,2,7,8‐dibenzacridine and 3,4,5,6‐dibenzacridine) were adsorbed from the gas phase and from liquid solution on highly dispersed silica gels with very different specific surface areas and pore sizes. The translational mobility of the adsorbed species was quantified by the triplet decay and the delayed fluorescence following bimolecular triplet‐triplet annihilation after pulsed laser irradiation. The decay kinetics were analyzed with conventional second order rate equations and with the fractal approach. The first method is reliable without limitations on adsorbents with large pore diameters. It yields second order annihilation constants of 4 times 1012‐6 times 1011 dm2 mol−1 s−1 depending on the masses and sterical requirements of the adsorbates. For the second method a spectral dimension ds= 4/3 was used. This method is quantitatively applicable to all heterocycles adsorbed on silica gel 60 that have very small pore sizes. An activation energy of 4.9 ± 0.5 kcal mol−1 was obtained for the translational diffusion of acridine on hydroxylated silica gel.