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Aufsatz
Flow and fiber orientation of fresh fiber reinforced concrete
(2021-12-14)
The orientation of the fibers in UHPC is decisive for the tensile strength and failure of the components. The mold filling strategy during casting of structural components dictates the flow routing and thus the fiber orientation. In addition, the orientation of the fibers also affects the flow behavior of the suspension. In measurements of rheological properties in concrete rheometers, strongly scattering measurements often occur. In this paper, a novel fiber orientation model for viscoplastic fluids is investigated ...
Aufsatz
Spiritual values shape taxonomic diversity, vegetation composition, and conservation status in woodlands of the Northern Zagros, Iran
(2021)
Sacred groves are under-researched in Muslim countries so that their overall contribution to biodiversity conservation remains unknown. We studied 22 sacred groves and 45 surrounding woodlands in Northern Zagros, Iran, to compare taxonomic diversity, vegetation composition, and the conservation status of plant species. Sacred groves had higher taxonomic diversity and a more valuable species pool by sheltering numerous endangered plant species. Multivariate analysis indicated a substantial difference in the vegetation ...
Aufsatz
Extended life cycle assessment reveals the spatially-explicit water scarcity footprint of a lithium-ion battery storage
(2021-01-12)
The life cycle water scarcity footprint is a tool to evaluate anthropogenic contributions to regional water scarcity along global supply chains. Here, we complement it by a classification of the risk from human water use, a comprehensive conceptualisation of water use and a spatially-explicit impact assessment to a midpoint approach that assesses the risk of on-site and remote freshwater scarcity. For a 2 MWh Lithium-ion battery storage, the quantitative Water Scarcity Footprint, comprising physically used water, ...
Aufsatz
Modelling stress‐state dependent nonlocal damage and failure of ductile metals
(2021-01-25)
Damage and failure of ductile metals is highly influenced by the stress state. In fact, void growth takes place under hydrostatic tensile loading and void coalescence leads eventually to ductile failure. A completely different damage mechanism occurs for shear dominated loading that results in void elongation within a narrow shear band. In order to account for both failure mechanisms, a stress state dependent damage model is proposed. The model is based on a continuum damage mechanics approach, whereby nonlinear ...
Aufsatz
The impact of livestock grazing and canopy gaps on species pool and functional diversity of ground flora in the Caspian beech forests of Iran
(2021-06-05)
Questions
Livestock grazing is an important disturbance in many forest ecosystems. While several studies have addressed the general impact of different grazing and light intensities on temperate forest ecosystems, little is known about how the combination of these two factors can affect the species pool and functional diversity of temperate forests.
Location
Oriental beech forests of northern Iran.
Methods
Vegetation and environmental data of 104 relevés were collected. These were assigned to four groups based ...
Aufsatz
The effect of biodynamic preparations on growth and fruit quality of giant pumpkin (Cucurbita maxima D.)
(2021-11-25)
Background
Food quality of agricultural crops depends on environmental conditions, production system and cultivation method. A plant-based nutrition with food rich in vitamins, minerals and secondary plant compounds with antioxidative properties promotes human health. This investigation was inspired by an increasing global issue on how to improve product quality while using alternative preparations. The main aim of a 3-year study was to investigate the influence of fermented manure and silica products on yield and ...
Aufsatz
A Comparative Analysis of Residential Care: A Five-Country Multiple Case-Design Study
(2021-12-13)
Background
Despite a global policy push toward the advancement of family- and community-based care, residential care for children and youth remains a relevant and highly utilized out-of-home care option in many countries, fulfilling functions of care and accommodation as well as education and treatment.
Objective
As part of a larger project involving five European countries (Finland, Germany, Italy, Lithuania, and Spain), the objective was “to map” the context and content of residential care in each country, thereby ...
Aufsatz
Net-mineralization of organic matter and greenhouse gas emissions from Quebracho tannin-enriched manure applied to acidic and alkaline soils
(2021-07-09)
Background
Mitigation strategies to reduce greenhouse gas emissions, ammonia volatilization, and nitrate leaching from agriculture are important for the management of environmental pollution and climate change. Tannins, which are water-soluble polyphenolic compounds, were found to reduce emissions in animal husbandry systems when supplemented to ruminant diets.
Aim
Two laboratory incubation experiments were conducted to investigate the effects of Quebracho tannin-enriched manure on carbon (C) and nitrogen (N) ...
Aufsatz
A monolithic approach toward coupled electrodynamic–thermomechanical problems with regard to weak formulations
(2021-11-11)
Weak formulations of boundary value problems are the basis of various numerical discretization schemes. They are classically derived applying the method of weighted residuals or a variational principle. For electrodynamical and caloric problems, variational approaches are not straightforwardly obtained from physical principles like in mechanics. Weak formulations of Maxwell’s equations and of energy or charge balances thus are frequently derived from the method of weighted residuals or tailored variational approaches. ...
Aufsatz
Measurement and analysis of residual stresses and warpage in fiber reinforced plastic and hybrid components
(2021-02-16)
Glass/carbon fiber reinforced plastic (GFRP/CFRP) and hybrid components have attracted increasing attention in lightweight applications. However, residual stresses induced in the manufacturing process of these components can result in warpage and, eventually, negatively affect the mechanical performance of the composite structures. In the present work, GFRP, CFRP, GFRP/steel and CFRP/steel hybrid components were manufactured through the prepreg-press-technology always employing the same process parameters. The residual ...