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Ionic liquids are well known for their high gas absorption capacity. It is shown that this is not a solvent constant, but can be enhanced by another factor of 10 by pore confinement, here of the ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate (EmimOAc) in the pores of carbon materials. A matrix of four different carbon compounds with micro- and mesopores as well as with and without nitrogen doping is utilized to investigate the influence of the carbons structure on the nitrogen uptake in the pore-confined EmimOAc. In general, the absorption is most improved for IL in micropores and in nitrogen-doped carbon. This effect is so large that it is already seen in TGA and DSC experiments. Due to the low vapor pressure of the IL, standard volumetric sorption experiments can be used to quantify details of this effect. It is reasoned that it is the change of the molecular arrangement of the ions in the restricted space of the pores that creates additional free volume to host molecular nitrogen.
"Deal of the Day" (DoD) platforms have quickly become popular by offering savings on local services, products and vacations. For merchants, these platforms represent a new marketing channel to advertise their products and services and attract new customers. DoD platform providers, however, struggle to maintaining a stable market share and profitability, because entry and switching costs are low. To sustain a competitive market position, DoD providers are looking for ways to build a loyal customer base. However, research examining the determinants of user loyalty in this novel context is scarce. To fill this gap, this study employs Grounded Theory methodology to develop a conceptual model of customer loyalty to a DoD provider. In the next step, qualitative insights are enriched and validated using quantitative data from a survey of 202 DoD users. The authors find that customer loyalty is in large part driven by monetary incentives, but can be eroded if impressions from merchant encounters are below expectations. In addition, enhancing the share of deals relevant for consumers, i.e. signal-to-noise ratio, and mitigating perceived risks of a transaction emerge as challenges. Beyond theoretical value, the results offer practical insights into how customer loyalty to a DoD provider can be promoted.
Driven mostly by the search for chemical syntheses under biocompatible conditions, so called "click" chemistry rapidly became a growing field of research. The resulting simple one-pot reactions are so far only scarcely accompanied by an adequate optimization via comparably straightforward and robust analysis techniques possessing short set-up times. Here, we report on a fast and reliable calibration-free online NMR monitoring approach for technical mixtures. It combines a versatile fluidic system, continuous-flow measurement of H-1 spectra with a time interval of 20 s per spectrum, and a robust, fully automated algorithm to interpret the obtained data. As a proof-of-concept, the thiol-ene coupling between N-boc cysteine methyl ester and ally] alcohol was conducted in a variety of non-deuterated solvents while its time-resolved behaviour was characterized with step tracer experiments. Overlapping signals in online spectra during thiol-ene coupling could be deconvoluted with a spectral model using indirect hard modeling and were subsequently converted to either molar ratios (using a calibration free approach) or absolute concentrations (using 1-point calibration). For various solvents the kinetic constant k for pseudo-first order reaction was estimated to be 3.9 h(-1) at 25 degrees C. The obtained results were compared with direct integration of non-overlapping signals and showed good agreement with the implemented mass balance. (C) 2017 Elsevier Inc. All rights reserved.
Background: There is an increasing awareness of the impact of parental risk perception on the weight course of the child and the parent's readiness to engage in preventive efforts, but only less is known about factors related to the parental perception of the right time for the implementation of preventive activities. The aim of this study was to examine parental perceptions of the appropriate time to engage in child weight management strategies, and the factors associated with different weight points at which mothers recognize the need for preventive actions.
Methods: 352 mothers with children aged 2-10 years took part in the study. We assessed mothers' perceptions of the actual and preferred weight status of their child, their ability to identify overweight and knowledge of its associated health risks, as well as perceptions of the right time for action to prevent overweight in their child. A regression analysis was conducted to examine whether demographic and weight related factors as well as the maternal general risk perception were associated with recognizing the need to implement prevention strategies.
Results: Although most of the parents considered a BMI in the 75th to 90th percentile a valid reason to engage in the prevention of overweight, 19% of the mothers were not willing to engage in prevention until their child reached the 97th percentile. Whereas the child's sex and the identification of an elevated BMI were significant predictors for parents' recognition of the 75th percentile as right point to engage in prevention efforts, an inability to recognize physical health risks associated with overweight silhouettes emerged as a significant factor predicting which parents would delay prevention efforts until a child's BMI reached the 97th percentile.
Conclusion: Parental misperceptions of overweight and associated health risks constitute unfavorable conditions for preventive actions. Feedback on the health risks associated with overweight could help increase maternal readiness for change.
This article provides a survey of the research carried out by Celtic scholars in Germany during the 15 years between 1980 and 1995. It is based on the respective bibliography published in 'Studia Celtica Japonica' 9 (1997). The major research fields covered are IE Studies, Celtic philology, linguistics, literature, archaeology and cultural studies.
An alternative method for the structure tuning of carbon nitride materials by using a supramolecular approach in combination with caffeine as lining-agent is described. The self-assembly of the precursor complex consisting of melamine and cyanuric acid can be controlled by this doping molecule in terms of morphology, electronic, and photophysical properties. Caffeine is proposed to insert as an edge-molecule eventually leading to hollow tube-like carbon nitride structures with improved efficiency of charge formation. Compared to the bulk carbon nitride, the caffeine-doped analogue possesses a higher photocatalytic activity for the degradation of rhodamineB dye. Furthermore, this approach is also shown to be suitable for the modification of carbon nitride electrodes.