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Reduction Behavior of Anisyl-substituted P-Ferrocenyl Phospholes
(2023-05-26)
P-Ferrocenylphospholes with differing substituents in α-position have been synthesized and their identity and purity was confirmed using multinuclear NMR spectroscopy, MS, elemental analysis and single crystal X-ray diffraction. Furthermore, the redox properties have been explored with electrochemical measurements. Transferring the reduction to a preparative scale using lithium leads to reductive P−C bond cleavage furnishing the corresponding phospholide which has been transformed to P-tert-butyl substituted phosphole. ...
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Attitude maneuvers avoiding forbidden directions
(2023-06-16)
Many space missions require the execution of large-angle attitude slews during which stringent pointing constraints must be satisfied. For example, the pointing direction of a space telescope must be kept away from directions to bright objects, maintaining a prescribed safety margin. In this paper we propose an open-loop attitude control algorithm which determines a rest-to-rest maneuver between prescribed attitudes while ensuring that any of an arbitrary number of body-fixed directions of light-sensitive instruments ...
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Wahrheit in Wittgensteins Spätphilosophie
(2023-06-21)
Truth in Wittgenstein′s Later Philosophy. In this paper I attempt to examine Wittgenstein′s understanding of truth in his later period. In doing so, I orient myself primarily on the remarks published as Philosophical Investigations and On Certainty. My primary aim in the destructive part is to show that his later philosophy neither espouses a redundancy and deflationary, nor an epistemic and anti-realist conception of truth. Both strands of interpretation are strongly represented in the debate. An examination of ...
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Pollen metabarcoding of museum specimens and recently collected bumblebees (Bombus) indicates foraging shifts
(2023-07-05)
Landscape changes, over time, lead to changes of floral resources available to pollinators, which in turn may result in the disappearance of ecologically specialized species. Here, we use pollen metabarcoding to infer historic and recent interactions between plants and bumblebees (Bombus). Bumblebees from Cuxhaven (Germany) were sampled from historical museum collections (1968/69) and in the field (2019). Pollen attached to their bodies was barcoded using multiple plant markers (ITS1, ITS2 and trnL-P6 loop). Our ...
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Critical evaluation of biochar effects on methane production and process stability in anaerobic digestion
(2023-07-18)
Biochar is an emerging biomaterial for managing residual biomass while simultaneously sequestering carbon. To extend the biochar value chain, applying biochar to enhance anaerobic digestion (AD) processes is gaining attention in the context of a circular economy and cascading use of biomass. However, the comparative effects of various biochar dosages under normal and severe AD conditions are still unclear. To further our understanding of its potential application, this work investigated the impact of adding various ...
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Increased heat stress reduces future yields of three major crops in Pakistan’s Punjab region despite intensification of irrigation.
(2023-02-27)
Climate change and variability threaten the sustainability of future food production, especially in semi-arid regions where water resources are limited and irrigated agriculture is widespread. Increasing temperatures will exacerbate evaporative losses and increase plant water needs. In this regard, higher irrigation intensities have been posited as a solution to mitigate climate change impacts in these regions. Here, using the agrohydrological model SWAT and the biophysical crop model APSIM, we show that this mitigation ...
Aufsatz
The relationship between accuracy in numerosity estimation, math achievement, and math interest in primary school students
(2023-07-10)
Estimation is a primary activity in everyday life, so getting it “right” in primary school provides a foundational basis in mathematical reasoning. This study focuses on numerosity estimation in primary mathematics, which is one of four types of estimation reported in literature. In numerosity estimation, a non-numerical quantitative representation is typically translated into a number. While it is assumed that fostering numerosity estimation has a great impact on the development of mathematical skills, research ...
Aufsatz
Biodynamic compost effects on soil parameters in a 27-year long-term field experiment
(2022-10-27)
Background
Soil samples were taken after 27 years from a long-term field experiment to study the effects of composted pure cattle farmyard manure (FYM) and two FYM treatments with biodynamic preparations on soil chemical and microbiological properties.
Methods
Soil organic carbon (SOC), total nitrogen, basal respiration, fungal ergosterol, microbial biomass C (MBC) and nitrogen (MBN) were analyzed in a 6-field crop rotation system, conducted as a randomized block design with six replicates. The multi-substrate-induced ...
Aufsatz
Mean girls, queen bees and iron maidens? Female leadership and accusations of workplace bullying
(2022-10-11)
We examined whether female leaders would be evaluated less favorably compared to male leaders regarding workplace bullying. Previous research has demonstrated that women violating prescriptive gender norms of communality experience backlash, and that female leaders are stereotyped of having a communality deficit. Building on that, we hypothesized (1) more moral outrage against and (2) more intentions to punish a female leader compared to a male leader. We further hypothesized (3) the accusations of ...
Aufsatz
The combined application of nitrogen and biochar reduced microbial carbon limitation in irrigated soils of West African urban horticulture
(2022-07-16)
Background:
Intensive wastewater irrigated urban horticulture in sub-Saharan West Africa receives high nutrient inputs, which lead to large gaseous and leaching losses. The addition of biochar to the usually sandy soils may reduce these losses and improve the habitat conditions for soil microorganisms. Two similar experiments focused on crop yields and nutrient balances have been carried out over a 2-year period in semi-arid Ouagadougou, Burkina Faso, and in sub-humid Tamale, Ghana, representing to some extent ...