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Fluorescence Microscopic Investigations of the Retarding Effect of Superplasticizers in Cementitious Systems of UHPC
(2020-02-27)
The adsorption of superplasticizer molecules to particle surfaces in cementitious systems is a very important aspect for the desired liquefaction of pastes and concretes. This way, the comb shaped polymers shield attractive forces between the particles and induce a well-dispersed, homogeneous suspension. These admixtures allow the usage of fine fillers even in combination with low amounts of mixing water, and thus, are the basis for modern high performance concretes. However, the adsorption does not cause beneficial ...
Aufsatz
Review of Flux Interaction of Differently Aligned Magnetic Fields in Inductors and Transformers
(2020-12-24)
Magnetic devices are used in the majority of power electronic applications, e.g. power electronic converters, mains filters or burst/surge protection. Typically, they are the bulkiest and most cost-intensive components. Flux interaction of differently aligned magnetic fields in inductors and transformers can be one opportunity for size and cost reduction. It enables controllable magnetic devices through an additional manipulated variable to improve application design. The presented article gives an overview about ...
Aufsatz
Adoption and utilisation of Zai pits for improved farm productivity in drier upper Eastern Kenya
(2020-03-06)
Inadequate and poorly distributed rainfall and declining soil fertility have led to low crop productivity in most smallholder farms in sub-Saharan Africa. As a result, there has been a renewed quest for sustainable and resource-use efficient agricultural production practices. Zai pit technology is a practice that has the potential to alleviate water stress and enhance soil fertility. We assessed the factors that influence farmers' adoption and utilisation of Zai pits in Tharaka-Nithi County in upper Eastern Kenya. ...
Aufsatz
The Impact of Missing Values on PLS, ML and FIML Model Fit
(2020)
Structural equation modelling has become widespread in the marketing research domain due to the possibility of creating and investigating latent constructs. Today, several estimation methods are available, each with strengths and drawbacks. This study investigates how the established estimation methods of partial-least-squares (PLS), maximum likelihood (ML) and full-information maximum likelihood (FIML) perform with an increasing percentage of missing values (MVs). The research was conducted by investigating an adapted ...
Aufsatz
On the Influence of Microstructure on the Corrosion Behavior of Fe–Mn–Al–Ni Shape Memory Alloy in 5.0 wt% NaCl Solution
(2020-10-03)
Herein the corrosion behavior of Fe–Mn–Al–Ni shape memory alloys characterized by different microstructures in a 5.0 wt% NaCl solution is investigated. Open circuit potential and potentiodynamic polarisation tests are conducted. Generally, Fe–Mn–Al–Ni shows corrosion properties being similar to pure iron. However, the polarization curves of single crystals indicate the presence of an unstable passive system. The corrosion damage is analyzed by means of optical microscopy and electron microscopy. It is revealed that ...
Aufsatz
Investigation of residual stresses in polypropylene using hot plate welding
(2020-08-05)
During the cooling process of the molten material, residual stresses appear because the reduced volume of the cooled material cannot fully fill the space formerly occupied by the molten material. The morphology in and around the weld is formed by different factors depending on the material and process parameters. Different morphological structures relate to different mechanical properties. The process parameters and the welding results including morphology and residual stress are linked together. In this article, ...
Aufsatz
Engaging stakeholders in traditional food products through dissemination of knowledge and innovation based in digital platforms
(2020-11-29)
The agrofood sector has a great sectorial and business dispersion, constituting, in parallel, a relevant space of the European and national economy. In addition to the economic and social impact, the growth of the sector is also an opportunity for the development of rural areas and agriculture, particularly in view of Europe's shortages in food raw materials. The need for continuous improvement, and market developments of this sector, require that innovation processes occur. This process has been facilitated by the ...
Aufsatz
An Exploration on Factors Influencing Certified and Farm-Saved Seed Use: A Case Study in Turkish Wheat Farming
(2020-11-29)
Seeds are an important input for wheat-growing, as is the case for all crop production. The type and quality of seed in crop production are the first condition for productivity and accordingly certified wheat seed use is being encouraged by the government since 2005 in Turkey. This study examined the factors affecting the certified seed and farmer (farm)-saved seed use in wheat farming in Turkey. The result of the analyses showed that there is a significant difference between farmers using certified seed and farm-saved ...
Aufsatz
Das ‚effiziente Museum‘ im Widerstand gegen die ‚Diktatur der Wand‘
(2020-05-12)
Der vorliegende Beitrag geht von der Annahme aus, dass es sich bei der innovativen Ausstellungspraxis der Nachkriegszeit um eine ‚zweite Museumsreform‘ handelt, einen theoretischen Neuansatz, der die gegenüber der Vorkriegszeit abweichende Ausstellungspraxis der Epoche erst verständlich werden lässt. Zur Überprüfung dieser These liegt der folgenden Studie eine systematische Erfassung von museumstheoretischen Stellungnahmen in den Kulturzeitschriften der Nachkriegszeit in mehreren westeuropäischen Ländern zugrunde, ...
Aufsatz
Influence of the degree of crystallinity and the surface free energy on the adhesion properties of different PLA/PBS blends in multicomponent injection molding
(2020-01-10)
Biocomposites made of biodegradable polymers have grown in interest due to their environmentally friendliness, considering that non-biodegradable polymers waste conduces to pollution, displaying high environmental impact in climatic changes. Therefore, in the presented study, biodegradable Poly (lactic acid) (PLA) and poly (butylene succinate) (PBS) were investigated as a series of PLA/PBS melt-blending compounds with the weight ratios of 50/50, 60/40, 70/30, 80/20 and 90/10. In a two-component injection molding ...