Search

Der Buchbeitrag gibt eine theoretische Übersicht zur Kommunikation mit Kampagnen und deren Wirkungen

Einige grundlegende Transformationen im soziokulturellen, politischen und massenmedialen Umfeld politischen Handelns legen es nahe, von einer sukzessiven Modernisierung der politischen Kommunikation zu sprechen. Als deren Kern kann die Medialisierung des Politischen identifiziert werden. Gemeint sind damit zunehmende Anpassungs- und Induktionsleistungen politischer Akteure gegenüber der System- und Handlungslogik der Massen- und Onlinemedien, die sich aus deren gesamtgesellschaftlichen Relevanzgewinn ergeben (Vowe 2006; Reinemann 2010; Strömbäck & Esser 2014).

Mit Öffentlichkeitsarbeit bzw. Public Relations (PR) wird, ähnlich wie im Journalismus, ein vielfältiges, heterogenes Tätigkeitsfeld bezeichnet, das sich zudem im historischen Prozess kontinuierlich gewandelt hat. Das PR-Verständnis wurde über lange Zeit von reflektierenden Einzelpersönlichkeiten aus dem Berufsfeld beeinflusst, d. h. vor allem von Praktikern und nicht von Wissenschaftlern.

As part of the European ACTRIS project, the first large Quadrupole Aerosol Chemical Speciation Monitor (Q-ACSM) intercomparison study was conducted in the region of Paris for 3 weeks during the late-fall - early-winter period (November-December 2013). The first week was dedicated to the tuning and calibration of each instrument, whereas the second and third were dedicated to side-by-side comparison in ambient conditions with co-located instruments providing independent information on submicron aerosol optical, physical, and chemical properties. Near real-time measurements of the major chemical species (organic matter, sulfate, nitrate, ammonium, and chloride) in the non-refractory submicron aerosols (NR-PM) were obtained here from 13 Q-ACSM. The results show that these instruments can produce highly comparable and robust measurements of the NR-PM total mass and its major components. Taking the median of the 13 Q-ACSM as a reference for this study, strong correlations (r > 0.9) were observed systematically for each individual Q-ACSM across all chemical families except for chloride for which three Q-ACSMs showing weak correlations partly due to the very low concentrations during the study. Reproducibility expanded uncertainties of Q-ACSM concentration measurements were determined using appropriate methodologies defined by the International Standard Organization (ISO 17025, 1999) and were found to be 9, 15, 19, 28, and 36 % for NR-PM, nitrate, organic matter, sulfate, and ammonium, respectively. However, discrepancies were observed in the relative concentrations of the constituent mass fragments for each chemical component. In particular, significant differences were observed for the organic fragment at mass-to-charge ratio 44, which is a key parameter describing the oxidation state of organic aerosol. Following this first major intercomparison exercise of a large number of Q-ACSMs, detailed intercomparison results are presented, along with a discussion of some recomme

© Author(s) 2015. Chemically resolved atmospheric aerosol data sets from the largest intercomparison of the Aerodyne aerosol chemical speciation monitors (ACSMs) performed to date were collected at the French atmospheric supersite SIRTA. In total 13 quadrupole ACSMs (Q-ACSM) from the European ACTRIS ACSM network, one time-of-flight ACSM (ToF-ACSM), and one high-resolution ToF aerosol mass spectrometer (AMS) were operated in parallel for about 3 weeks in November and December∼2013. Part 1 of this study reports on the accuracy and precision of the instruments for all the measured species. In this work we report on the intercomparison of organic components and the results from factor analysis source apportionment by positive matrix factorisation (PMF) utilising the multilinear engine 2 (ME-2). Except for the organic contribution of mass-to-charge ratio m/z 44 to the total organics (f44), which varied by factors between 0.6 and 1.3 compared to the mean, the peaks in the organic mass spectra were similar among instruments. The m/z 44 differences in the spectra resulted in a variable f44 in the source profiles extracted by ME-2, but had only a minor influence on the extracted mass contributions of the sources. The presented source apportionment yielded four factors for all 15 instruments: hydrocarbon-like organic aerosol (HOA), cooking-related organic aerosol (COA), biomass burning-related organic aerosol (BBOA) and secondary oxygenated organic aerosol (OOA). ME-2 boundary conditions (profile constraints) were optimised individually by means of correlation to external data in order to achieve equivalent / comparable solutions for all ACSM instruments and the results are discussed together with the investigation of the influence of alternative anchors (reference profiles). A comparison of the ME-2 source apportionment output of all 15 instruments resulted in relative standard deviations (SD) from the mean between 13.7 and 22.7 % of the source's averag

The paper describes examples of net diastereotopic-group-selective radical processes having the unusual feature that a single product is formed even though the key reaction of the two diastereotopic radical precursors is nonselective. For example, reaction of (R)-N-(cyclohex-2-en-1-yl)-N-(2,6-diiodo-4- methylphenyl)acetamide with tributyltin hydride produces 1-((4aR,9aR)-6-methyl- 2,3,4,4a-tetrahydro-1H-carbazol-9(9aH)-yl)ethanone with high product selectivity and in high yield. Analysis of the concentration profiles of the closed-shell intermediates at the halfway point of the reaction shows that nonselective abstraction of diastereotopic iodides by tin radicals occurs, leading to diastereomeric aryl radicals. These isomeric intermediates evolve via two nonintersecting reaction pathways, cyclization and bimolecular trapping or vice versa, into the same final product. Origins of the selectivity are suggested on the basis of conformational analysis of the products using both X-ray crystallography and density functional theory calculations. © 2011 American Chemical Society.

The rate constant for phosphanylation of an aryl radical with trimethylstannyl diphenylphosphane (Me3SnPPh2) has been measured as kphos ≈ 9 × 108 M-1 s -1. Aryl radicals derived from several axially chiral o-haloanilides are trapped by Me3SnPPh2 with complete retention of axial chirality as shown by oxidation of the phosphanes to give stable, easily analyzed phosphane oxides or sulfides. Double phosphanylations of o,o′-dihaloanilides followed by treatment with H2O2 or S8 in either order give enantiomers of a mixed diphosphane oxide sulfide. Chemodivergent trapping of diastereomers of an N-(cyclohex-2-enyl) anilide anilide is observed. For one isomer, the cyclization precedes the Me3SnPPh2 trapping, while for the other isomer direct trapping with Me3SnPPh2 supersedes the cyclization. The products are chiral triaryl phosphanes, oxides, and sulfides that are potentially interesting ligands in asymmetric catalysis. © 2010 American Chemical Society.

The title compounds were generated by deprotonation of different benzyl-type carbamates with sec-butyllithium in the presence of chiral diamines (-)-sparteine or diisopropyl and di-tert-butyl bis(oxazoline)s. These lithiated species exhibit configurational lability at -78 8C. In the case of the chiral di-tert-butyl bis(oxazoline), the equilibrium of the epimeric complexes can be used synthetically to obtain highly enantioenriched secondary benzyl carbamates. The enantiodetermining step was proven to be a dynamic thermodynamic resolution. The absolute configurations of the products were determined, and the stereochemical pathways of selected substitution reactions were thus elucidated. High level quantum chemical investigations were performed to gain insight into the experimentally investigated system. To obtain an accuracy for the energy difference (DDH) between two epimeric complexes of about 0.5 kcalmol-1 as well as the correct sign, a theoretical procedure was established. It included geometry optimization at the dispersion-corrected DFT level, computation of zero-point vibrational energies, and single-point SCS-MP2 energy calculations with large atomic-orbital basis sets.

Association constants for the interaction of almost insoluble substrates with triphenylene ketal-based receptors in toluene have been determined by means of an extraction method employing the corresponding radio-labelled substrates. Flexible and more polar receptors tend to aggregate and exhibit inferior extraction qualities. Binding constants in toluene were found to be in the range 105–107M-1 which is significantly higher than in dichloromethane. X-ray analyses indicate the direct participation of a water molecule in the binding process, which may account for the surprisingly small effect of moisture in the solvent on the stability of the complexes.

Stereoselective addition of aldehydes 4 to metallated 1-(1-cycloalkenyl) methyl N,N-diisopropylcarbamates 1 gave cyclic homoaldol adducts 6. By applying the (-)-sparteine method, enantiomerically enriched products were obtained. These were oxidatively cyclized to diastereomerically pure ¿-lactones 8 via the ¿-lactol ethers 7. After deprotonation of ¿-lactones 8 with lithium hexamethyldisilazide, a further substitution was achieved. By trapping the lactone enolates 11 with ß-naphthylmethyl bromide, single diastereomers of ¿-lactones 12 were produced.

Several (cycloalk-1-enyl)methyl N,N-diisopropylcarbamates 11 were synthesised by three different methods and their asymmetric deprotonation by butyllithium/(-)-sparteine was investigated. The ratios of epimeric ion pairs 18·4/epi-18·4 were determined by (stereospecific) trimethylsilylation, forming the products 19/ent-19. Lithiated 2-unsubstituted (cyclopent-1-enyl) methyl carbamates, such as 11a or 11h, epimerise rapidly at -78 °C and the thermodynamically controlled ratio is opposite to the kinetically achieved ratio. High configurational stability was found for the 2-methylcycloalk-1-enyl derivatives 11d, 11e and 11j. These turned out to be valuable reagents for enantioselective homoaldol reaction; er values of up to 96:4 could be achieved. X-ray crystal structure analyses with anomalous diffraction, obtained from the heavy atom containing products 22, 23b, 27d, and 27e derived from (2-methylcyclopentenyl)methyl and (2-methyl-cyclohexenyl)methyl reagents, established the (1S) configuration of the major lithium compound. Thus, the kinetically controlled deprotonation of the corresponding allyl carbamates removes the (pro-S) proton. Overall, a simple method for the enantioselective synthesis of cyclic homoaldol adducts from achiral precursors is reported.