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Liquid Silicone Rubber Foamed with Thermoplastic Expandable Microspheres
(2022-05-25)
To reduce the material costs as well as the density of Liquid Silicone Rubber (LSR), LSR foams can be produced in an injection molding process. Expandable thermoplastic microspheres can be used as blowing agents. This publication deals with the analysis of the cell structure of these LSR foams. For this purpose, cylindrical disks are injection molded and examined for their cell structure as a function of different proportions of microspheres using a scanning electron spectroscope. In addition, the density of the ...
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Millimetre scale aeration of the rhizosphere and drilosphere
(2022-06-22)
Soil aeration is a critical factor for oxygen-limited subsoil processes, as transport by diffusion and advection is restricted by the long distance to the free atmosphere. Oxygen transport into the soil matrix is highly dependent on its connectivity to larger pore channels like earthworm and root colonised biopores. Here we hypothesize that the soil matrix around biopores represents different connectivity depending on biopore genesis and actual coloniser. We analysed the soil pore system of undisturbed soil core ...
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Using heuristic worked examples to promote solving of reality-based tasks in mathematics in lower secondary school
(2022-04-19)
This study examined whether learning with heuristic worked examples can improve students’ competency in solving reality-based tasks in mathematics (mathematical modeling competency). We randomly assigned 134 students in Grade 5 and 180 students in Grade 7 to one of three conditions: control condition (students worked on reality-based tasks), worked example condition (students studied worked examples representing a realistic process of problem-solving by fictitious students negotiating solutions to the tasks), and ...
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Gender Representations Elicited by the Gender Star Form
(2022-02-28)
In many languages, masculine language forms are not only used to designate the male gender but also to operate in a generic fashion. This dual function has been found to lead to male biased representations when people encounter the generic masculine. In German, the now predominant substitute is the gender star form (e.g., Athlet*innen). In two experiments, we examined gender representations elicited when reading the gender star form (vs. generic masculine vs. pair forms). We found that, following the generic masculine, ...
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Promoting quality of extended education at primary schools in Sweden and Germany: A comparison of guidelines and children’s perspectives
(2022-05-30)
Internationally, provisions of extended education programs and related research are increasing. Over the past decade, many governments have established quality standards according to their specific goals. The aim of this comparative case study of School-Age Educare Centers in Sweden and all-day schools in Germany is to identify steps to ensure high quality of extended education in line with requirements for future education. We analyze the perspectives of policymakers, reflected in guidelines and quality standards ...
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Adhesion of liquid silicone rubber (LSR) polypropylene (PP) composites after storage tests
(2022-07-15)
The objective of this study is the production of liquid silicone rubber (LSR) polypropylene (PP) composites. To create adhesion between LSR and thermoplastics, self-adhesive LSR types are available on the market. However, these materials are not effective for commodity thermoplastics, such as PP and no adhesion can be achieved between these two components. Therefore, the PP surface was activated by means of silicatization (flame treatment). Subsequently, the LSR was applied on the activated PP by an overmolding ...
Aufsatz
Demonstration of Hybrid Effect in Single Fiber Pull-Out Tests for Glass/Cellulose-Reinforced Polypropylene with Different Fiber–Matrix Adhesions
(2022-06-21)
In hybrid fiber reinforcement, the combination of glass and regenerated cellulose fibers is a promising combination because the different properties of the fibers can be combined. The properties of the regenerated cellulose fiber in combination with the absorption of energy by fiber pull-outs can thus significantly increase the toughness of the composite in the event of failure, while the glass fiber significantly increases the stiffness and strength due to its properties. In this study, the interaction of the two ...
Aufsatz
Socialism Order of Worth and Analytical Adequacy Axiom
(2022-06-15)
Boltanski and Thévenot (On justification. Economies of worth, Princeton University Press, Princeton, 2006) constructed in their seminal work On Justification the Orders of Worth (OW) framework as a research program for further empirical and theoretical development. This article suggests two methodological additions to extend the analytical capacities of the OW framework: The Socialism OW and the analytical adequacy axiom. The polito-philosophical Socialism OW, which acknowledges '(collective) welfare' as its mode of ...
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SDG Performance in Local Organic Food Systems and the Role of Sustainable Public Procurement
(2022-09-14)
Alternative food systems have occupied a steady niche in the food systems transformation discourse as one of the transformative pathways capable of addressing many of the United Nations Sustainable Development Goals (SDGs). Being one of the alternative approaches, organic food systems are often in the spotlight of transformation discussion. While their outcomes and, to a lesser extent, potential to address the SDGs have been documented, the attempts to provide empirical evidence for the latter contribution are largely ...
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Evidence for Electron Transfer from the Bidirectional Hydrogenase to the Photosynthetic Complex I (NDH-1) in the Cyanobacterium Synechocystis sp. PCC 6803
(2022-08-10)
The cyanobacterial bidirectional [NiFe]-hydrogenase is a pentameric enzyme. Apart from the small and large hydrogenase subunits (HoxYH) it contains a diaphorase module (HoxEFU) that interacts with NAD(P)+ and ferredoxin.
HoxEFU shows strong similarity to the outermost subunits (NuoEFG) of canonical respiratory complexes I. Photosynthetic complex I (NDH-1) lacks these three subunits. This led to the idea that HoxEFU might interact with NDH-1 instead. HoxEFUYH utilizes excited electrons from PSI for photohydrogen ...