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Aufsatz
Characterization of charcoal and firewood ash for use in African peri-urban agriculture
(2020-03-05)
Background
Ample quantities of ashes generated from domestic biomass energy combustion in Ghanaian kitchens are currently disposed of despite their potential agricultural value. This study aimed to investigate the potential agricultural value of charcoal and firewood ashes in terms of differences in the chemical and mineralogical compositions, and to identify the suitability of aqua regia, H2SO4, vinegar and distilled water to extract plant nutrients (Ca, Mg, K, Na, and P). The chemical compositions were determined ...
Aufsatz
Mineralisation of distinct biogas digestate qualities directly after application to soil
(2020-11-02)
Biogas is an important energy source produced by the anaerobic fermentation of raw faecal slurries and plant residues. Separation of the total digestate increases the fertilizer quality of the liquid fraction and the carbon sequestration potential of the solid fraction. A 12-day incubation study was carried out to investigate the relationships between the chemical composition of different digestate qualities and the immediate response of soil microbial activity and biomass indices. The highest cumulative (Σ) CO2-C ...
Aufsatz
Effect of Surfactants on the Flow Patterns of Horizontal Tube Bundles with a Falling Film
(2020-03-24)
The influence of two alcoholic surfactants on the flow patterns of falling film tube bundles is investigated. The flow patterns are measured in a single‐stage absorption chiller in the absence of surfactants. The surface tension of H2O/aqueous LiBr solution with different concentrations of 1‐octanol and 2‐ethylhexanol is measured at low pressure in a saturated atmosphere. Small quantities of surfactants in the aqueous solution do not have an influence on the flow patterns of the condenser and evaporator, while a shift ...
Aufsatz
A structural topic model approach to scientific reorientation of economics and chemistry after German reunification
(2020-08-05)
The detection of differences or similarities in large numbers of scientific publications is an open problem in scientometric research. In this paper we therefore develop and apply a machine learning approach based on structural topic modelling in combination with cosine similarity and a linear regression framework in order to identify differences in dissertation titles written at East and West German universities before and after German reunification. German reunification and its surrounding time period is used because ...
Aufsatz
Exploration of production conditions: a step towards the development of a community-based breeding program for Butana cattle
(2020-11-17)
In Sudan, many Butana cattle farmers practice indiscriminate crossbreeding to improve the milk yield performance of cows, as organized breeding programs are lacking. Objectives of this study were to identify the current production conditions of Butana cattle and to determine farmers’ production objectives and trait preferences using a field survey. The overall aim was to explore the possibility of establishing a community-based breeding program for the genetic improvement of the breed. A semi-structured questionnaire ...
Aufsatz
Combined leaching and plant uptake simulations of PFOA and PFOS under field conditions
(2020-08-31)
Per- and polyfluoroalkyl substances (PFASs) are used in industrial production and manufacturing but were repeatedly detected in agricultural soils and therefore in cash crops in recent years. Dissipation of perfluoroalkyl acids (PFAAs), a sub-group of PFASs, in the environment was rather attributed to the formation of non-extractable residues (NER) than to degradation or transformation. Currently, there are no models describing the fate of PFAAs in the soil-plant continuum under field conditions, which hampers an ...
Aufsatz
Editorial
(2020-12-21)
Der „Blickpunkt“ dieser Ausgabe widmet sich unter dem Titel „Zusammenhalt | diferença“ also Fragen, die die Möglichkeiten, gesellschaftlichen Zusammenhalt herzustellen, unter Beachtung sozialer Ungleichheiten und Differenz diskutieren. Dabei wird der Blick gerichtet auf Brasilien und eine Praxis, die sich wesentlich
dokumentiert in den dortigen sozialen Bewegungen und den über diese initiierten Formen der Herstellung von sozialen Kontexten.
Aufsatz
Consumers’ Emotion Attitudes towards Organic and Conventional Food: A Comparison Study of Emotional Profiling and Self-Reported Method
(2020-01-10)
Emotions represent a major driver behind a consumption behavior. It may provide more important information beyond consumers’ preferences. This study contributes to a better understanding of the discrepancy in emotion attitudes towards organic versus conventional food using a cognitive survey and real food consumption experience. An emotional profiling under informed and uninformed condition, a cognitive survey, and a rapid forced-choice test were carried out with 46 consumers. Our work detected a yawning gap in ...
Aufsatz
Spatial and Temporal Dynamics of Urban Wetlands in an Indian Megacity over the Past 50 Years
(2020-02-17)
Asian megacities have attracted much scientific attention in the context of global urbanization, but few quantitative studies analyze wetland transformation in the rural–urban interface. With its rampant growth and transformation from a tree-lined “Garden City” to a busy megalopolis with often-blocked highways and large built-up areas, Bengaluru (Karnataka, S-India) is a good example for assessing how urbanization has led to the acute degradation of wetlands. We therefore investigated long-term land cover and wetland ...
Aufsatz
Cross-π-conjugated enediyne with multioptic metal binding sites
(2020-10-20)
The synthesis of an enediyne molecule functionlized with different metal coordination sites in a cross-pconjugated fashion is reported. Using Pd-mediated cross-coupling reactions, 2,20-bipyridine units were attached at the periphery of diazafluorenemethylidene to obtain a multitopic ligand. UV-vis spectrosopic investigations along with electrochemical analyses reveal electronic communication along the conjugated path reflected in red-shifted absorption spectra and shifts of reduction potentials. The properties of the ...