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N1,N2-diphenylacenaphthylene-1,2-diimines (BIANs) have been used to reduce the undesired high viscosity of alkyl magnesium solutions, which are known to form polymeric structures. In order to understand the mechanisms, analyses of the BIAN alkyl magnesium solutions have been carried out under inert conditions with SEC-MS, NMR, and FTIR and were compared to the structures obtained from HPLC-MS, FTIR, and NMR after aqueous workup. While viscosity reduction was shown for all BIAN derivatives used, only the bis (diisopropyl)-substituted BIAN could be clearly assigned to a single reaction product, which also could be reused without loss of efficiency or decomposition. All other derivatives have been shown to behave differently, even under inert conditions, and decompose upon contact with acidic solvents. While the chemical reactions observed after the workup of the used BIANs are dominated by (multiple) alkylation, mainly on the C = N double bond, the observation of viscosity reduction cannot be assigned to this reaction alone, but to the interaction of the nitrogen atoms of BIANs with the Mg of the alkyl magnesium polymers, as could be shown by FTIR and NMR measurements under inert conditions. [ABSTRACT FROM AUTHOR]

Accurate dietary analysis of energy, nutrient intake, and meal timing in human studies using traditional dietary assessment methods (e.g., food records) is challenging and time-consuming. The widespread use of smartphones, tablets, and nutrition applications (apps) can overcome some of these problems. The objective of this study was to evaluate the validity of an FDDB smartphone app and food database compared with PRODI®—a professional platform for nutritional counselling using the German Nutrient Database. Dietary records were collected from 10 subjects participating in the crossover intermittent fasting trial for 2 weeks at baseline and during the eating timeframe of 8 h (early or late in the course of the day). The FDDB app and database enabled a quicker and less sophisticated analysis of food composition and timing than the PRODI® software. Good agreement between the methods was found for energy and macronutrient intakes, while the FDDB data on most micronutrients and saturated/unsaturated fat intake were unreliable. In contrast to PRODI®, FDDB provided effective assessment of timely compliance, making it a promising tool for chrononutritional studies. Thus, the FDDB app is comparable to the traditional PRODI® dietary assessment method, and can be effectively used in human dietary trials and medical practice for specific goals. [ABSTRACT FROM AUTHOR]

Magnesium alkyls such as butyl octyl magnesium and butyl ethyl magnesium are used as precursors for highly active and water-free magnesium chloride support materials for Ziegler–Natta catalysts. These alkyls show a high viscosity in hydrocarbon solvents which negatively affect their industrial application. Density functional theory (DFT) calculations supported the hypothesis that magnesium alkyls can form oligomeric chain structures responsible for the high viscosity. Heterocumulenes such as isocyanates, isothiocyanates and carbodiimides were studied as additives reducing the viscosity, supported by DFT calculations. The modified alkyls have further been tested in catalyst synthesis and in the polymerization of ethylene. The polymerization results showed high activities and similar polymer properties compared with a catalyst prepared without modified magnesium alkyl. [ABSTRACT FROM AUTHOR]

Mild non-ionic sucrose ester surfactants can be employed to produce lipid-based drug delivery systems for dermal application. Moreover, sucrose esters of intermediate lipophilicity such as sucrose stearate S-970 possess a peculiar rheological behavior which can be employed to create highly viscous semi-solid formulations without any further additives. Interestingly, it was possible to develop both viscous macroemulsions and fluid nanoemulsions with the same chemical composition merely by slight alteration of the production process. Optical light microscopy and cryo transmission electron microscopy (TEM) revealed that the sucrose ester led to the formation of an astonishing hydrophilic network at a concentration of only 5% w/w in the macroemulsion system. A small number of more finely structured aggregates composed of surplus surfactant were likewise detected in the nanoemulsions. These discoveries offer interesting possibilities to adapt the low viscosity of fluid O/W nanoemulsions for a more convenient application. Moreover, a simple and rapid production method for skin-friendly creamy O/W emulsions with excellent visual long-term stability is presented. It could be shown by franz-cell diffusion studies and in vitro tape stripping that the microviscosity within the semi-solid formulations was apparently not influenced by their increased macroviscosity: the release of three model drugs was not impaired by the complex network-like internal structure of the macroemulsions. These results indicate that the developed semi-solid emulsions with advantageous application properties are highly suitable for the unhindered delivery of lipophilic drugs despite their comparatively large particle size and high viscosity. [ABSTRACT FROM AUTHOR]