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Aufsatz
Coinage Metal Complexes of the Carbenic Tautomer of a Conjugated Mesomeric Betaine Akin to Nitron
(2017-07-07)
This study was motivated by our recent observation that the analytical reagent Nitron (2) is an “instant carbene”, whose reaction with coinage metal salts MX afforded complexes of its carbenic tautomer 1,4-diphenyl-3-phenylamino-1,2,4-triazol-5-ylidene (2′). Our aim was to establish an alkyl homologue of 2 in order to achieve a carbenic tautomer of higher donicity. For this purpose 1-tert-butyl-4-methyl-1,2,4-triazol-4-ium-3-tert-butylaminide (6) was synthesized. Its reactions with MX afforded complexes of the carbenic ...
Aufsatz
Adoption of Organic Farming as an Opportunity for Syrian Farmers of Fresh Fruit and Vegetables: An Application of the Theory of Planned Behaviour and Structural Equation Modelling
(2017-11-04)
Exporting organic fresh fruit and vegetables (FFV) to the European Union could represent a great opportunity for Syrian farmers and exporters. Yet, the organic sector in Syria is comparatively young and only a very small area of FFV is organically managed. To date, little is known about Syrian farmers’ attitudes towards organic FFV production. Therefore, the aim of this study was to explore the intentions and attitudes of Syrian farmers of FFV towards organic farming and how likely they are to convert their farms to ...
Aufsatz
Heavy Metals and Polycyclic Aromatic Hydrocarbons in Urban Leaf Litter Designated for Combustion
(2017-03-03)
Vast amounts of leaf litter have to be disposed of by city administrations. This biomass has the potential for energy conversion, but contamination with pollutants can adversely affect this usage. We investigated leaf litter samples from the city of Kassel by analyzing their heavy metal and polycyclic aromatic hydrocarbon (PAH) concentrations. Leaf samples were indeed contaminated with heavy metals and PAHs and contamination was influenced by provenience and collection technique. A simple cleaning system of washing ...
Aufsatz
Crack path predictions in fiber reinforced composites
(2017-09-06)
Composite materials exhibit beneficial features compared to conventional engineering material, e.g. a comparable strength and a reduced weight at the same time. To fully exploit these beneficial properties within technical structures, fracture mechanical concepts must be taken into account. The global fracture behavior in composite materials is related to the local delamination at interfaces between matrix and inclusion as well as the local fracture behaviors of the constituents. Because of their structure, the global ...
Aufsatz
Die Welt in Karten. Umbrüche und Kontinuitäten im Mittelalter
(2017-06-28)
This paper addresses the changes and continuities within the wide range of cartographic practices that existed in the Middle Ages. Following introductory thoughts on methodological issues, the text focuses on three different types of maps, all of which represent the world in its entirety: schematic maps, world maps and nautical charts. Within different texts, as independent artifacts or as atlases, these maps were employed for diverse purposes, such as the representation of fundamental principles, of encyclopaedic ...
Aufsatz
Las tradiciones discursivas, la pragmalingüística y la lingüística del discurso
(2017)
El concepto de tradición discursiva desarrollado por la lingüística románica es central para una lingüística de enfoque cultural. Este concepto se basa en el modelo coseriano de la competencia lingüística, del cual se deduce la definición de las tradiciones discursivas. Una cuestión central de la lingüística con enfoque cultural es saber según qué principios, reglas y tradiciones se rigen los hablantes al realizar tareas comunicativas. El modelo de Coseriu abarca la sistematicidad lingüística de estas reglas y ...
Aufsatz
Fusion of Ultrasonic and Spectral Sensor Data for Improving the Estimation of Biomass in Grasslands with Heterogeneous Sward Structure
(2017-01-21)
An accurate estimation of biomass is needed to understand the spatio-temporal changes of forage resources in pasture ecosystems and to support grazing management decisions. A timely evaluation of biomass is challenging, as it requires efficient means such as technical sensing methods to assess numerous data and create continuous maps. In order to calibrate ultrasonic and spectral sensors, a field experiment with heterogeneous pastures continuously stocked by cows at three grazing intensities was conducted. Sensor ...
Aufsatz
Social Loafing in the Refugee Crisis: Information about Existing Initiatives Decreases Willingness to Help
(2017-05-11)
In light of the European refugee situation, we investigate how information about others’ support influences individuals’ willingness to help. When individuals see information about other people supporting refugees, they may either be influenced by a descriptive norm, and act accordingly. Alternatively, they may perceive that others are already doing the job, and thus engage in social loafing. In an experiment (N = 132), we tested these competing predictions. Specifically, participants were exposed to a map of Germany ...
Aufsatz
Phenotypic diversity, major genes and production potential of local chickens and guinea fowl in Tamale, northern Ghana
(2017-06-26)
Objective:
Our study provides information on phenotypes of local chickens and guinea fowl and their body measures as well as on major genes in local chickens in northern Ghana.
Methods:
Qualitative and morphometric traits were recorded on 788 local chickens and 394 guinea fowl in urban households in Tamale, Ghana.
Results:
The results showed considerable variation of color traits and numerous major genes in local chickens, while color variations and related genotypes in guinea fowl were limited. In local chickens, ...
Aufsatz
The Positive Facet of Self-compassion Predicts Self-reported Use of and Attitudes toward Desirable Difficulties in Learning
(2017-08-09)
Previous research found that introducing difficulties and challenges during learning has desirable outcomes. With the present work, we investigated the question how the use of and the attitudes toward such learning strategies (so-called desirable difficulties) are related to self-compassion, a concept that describes the tendency to be understanding and kind to oneself when confronted with negative experiences. Evidence suggests self-compassion to be linked to less fear of failing, and further to higher control beliefs ...