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Simultaneous impact modified and chain extended glass fiber reinforced poly(lactic acid) composites: Mechanical, thermal, crystallization, and dynamic mechanical performance
(2021-02-05)
Herein, glass fiber (GF) reinforced binary, ternary, and quaternary poly(lactic acid) (PLA) composites were prepared. Toughening, and chain extension of PLA was achieved through the incorporation of impact modifier and chain extender and their concurrent effects on the spectroscopic, crystallization, mechanical, thermal, and thermomechanical properties of the composites were investigated. High mechanical properties of GF influenced the mechanical performance of the composites. However, GF alone could not restrict the ...
Aufsatz
Performance comparison of a fixed-bed solar grain dryer with and without latent heat storage
(2024-04-21)
Latent heat storage has gained attention as an energy storage method for solar drying due to its high storage density. However, its overall impact in drying performance has not been sufficiently investigated. This study presents detailed, validated mathematical models necessary for the transient simulation of a solar dryer with latent heat storage with the aim of assessing the effect that such storage has on the deep bed drying of wheat. Computer simulations were run with weather data from Germany. A fixed bed dryer ...
Aufsatz
Boundary Work Tactics and Their Effects on Information and Communication Technology Use After Hours and Recovery
(2023-10-16)
With an increasing use of work-related technologies after hours and mobile working, boundaries between work and personal life domains blur more and more, impairing recovery. Qualitative studies have shown that individuals use various boundary work tactics to actively manage their work–nonwork boundaries. However, it remains largely unknown how the use of such tactics contributes to recovery. This research differentiates types of availability-related boundary work tactics and organizes them according to their underlying ...
Aufsatz
Improving acid-stressed anaerobic digestion processes with biochar towards a combined biomass and carbon management system
(2024-03-06)
Interest in biochar as an additive to enhance anaerobic digestion (AD) has grown in the context of biomass cascading use and the 2050 net-zero goal. However, few studies have investigated the effects of biochar on AD from a biochar production perspective, including biomass feedstocks and pyrolysis temperatures. To valorise biomass and better understand the mechanisms and environmental implications of using biochar in AD, this study investigated the effects of distinct biochar types on AD under acid stress-induced ...
Aufsatz
Development and Process Integration of an Alternative Demoulding System for High-Pressure Die Casting Using a Contoured Vacuum Mask
(2024-06-11)
This study presents the development and process integration of an alternative demoulding system for high-pressure die casting. The system is aimed at the removal of large structural castings, which are becoming increasingly popular in the industry under the terms mega- and gigacasting. The development differs from conventional systems in the fact that it completely avoids ejectors and realises the demoulding via the principle of vacuum suction cups. Preliminary tests were carried out in which various established ...
Aufsatz
Investigations of lightweight concrete by in situ compression tests using high-resolution computed tomography (μ-CT)
(2024-02-24)
The fracture behaviour of concrete is studied in various micro- and macrodamage models. This is important for estimating serviceability and stability of concrete structures. However, a detailed understanding of the material behaviour under load is often not available. In order to better interpret the fracture behaviour and pattern, images of lightweight concrete were taken using a highresolution computed tomography (μ-CT) scanner. The samples were loaded between the taken images and the load was kept constant during ...
Aufsatz
Effect of full-sib and S2-selection on a sweet corn population (Zea mays convar. saccharata)
(2024-04-26)
Sweet corn breeding goals differ from grain or silage corn. Sweet corn goals focus on marketable yield including several quality traits. This study explores the effect of a single cycle of full-sib selection and S2 selection on improving the marketable yield of an open-pollinated sweet corn population. The selected populations were subsequently compared in four environments for several plant-, yield- and quality traits relative to the original population. Analysis of variance was used to detect selection progress and ...
Aufsatz
Fluoropyrimidines trigger decay of hypomodified tRNA in yeast
(2024-06-10)
Therapeutic fluoropyrimidines 5-fluorouracil (5-FU) and 5-fluorocytosine (5-FC) are in long use for treatment of human cancers and severe invasive fungal infections, respectively. 5-Fluorouridine triphosphate represents a bioactive metabolite of both drugs and is incorporated into target cells’ RNA. Here we use the model fungus Saccharomyces cerevisiae to define fluorinated tRNA as a key mediator of 5-FU and 5-FC cytotoxicity when specific tRNA methylations are absent. tRNA methylation deficiency caused by loss of ...
Aufsatz
Optimal photoelectron circular dichroism of a model chiral system
(2024-06-03)
We optimize the internuclear geometry and electronic structure of a model chiral system to achieve a maximal photoelectron circular dichroism (PECD) in its one-photon ionization by circularly polarized light. The electronic structure calculations are performed by the single center method, while the optimization is done using quantum alchemy employing a Taylor series expansion. Thereby, the effect of bond lengths and uncompensated charge distributions on the chiral response of the model is investigated theoretically ...
Aufsatz
At the limits of bisphosphonio-substituted stannylenes
(2023-12-13)
Donor stabilization of Sn(II) and Pb(II) halides with 1,1’-ferrocenylene bridged bisphosphanes has been explored for Fe(C₅H₄P(C6H₅)₂)₂ (dppf), and Fe(C₅H₄PH(C₄H9))₂. These bisphosphanes are reacted with SnBr₂ and PbCl₂ with and without additional Lewis acid (AlCl₃) forming acyclic and cyclic donor adducts from which the latter represent bisphosphoniotetrylenes. Since dynamic exchange in solution is observed, characterization includes solution and solid-state NMR in addition to SC-XRD, amended by DFT calculations.