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Aufsatz
Asymptotic model for shape resonance control of diatomics by intense non-resonant light
(2015)
We derive a universal model for atom pairs interacting with non-resonant light via the polarizability
anisotropy, based on the long range properties of the scattering. The corresponding dynamics can be
obtained using a nodal line technique to solve the asymptotic Schrödinger equation. It consists of
imposing physical boundary conditions at long range and vanishing the wavefunction at a position
separating the inner zone and the asymptotic region. We show that nodal lines which depend on the
intensity of the ...
Aufsatz
Femtosecond wavepacket interferometry using the rotational dynamics of a trapped cold molecular ion
(2015)
A Ramsey-type interferometer is suggested, employing a cold trapped ion and two time-delayed offresonant
femtosecond laser pulses. The laser light couples to the molecular polarization anisotropy,
inducing rotational wavepacket dynamics. An interferogram is obtained from the delay dependent
populations of the final field-free rotational states. Current experimental capabilities for cooling and
preparation of the initial state are found to yield an interferogram visibility of more than 80%. The
interferograms can ...
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
Dairy Cows Are Limited in Their Ability to Increase Glucose Availability for Immune Function during Disease
(2023-03-12)
Simple Summary
Both immune defense and milk synthesis require large amounts of energy, particularly from glucose, resulting in competition between these functions if glucose availability is limited. Based on comprehensive data on cow nutrient intake and on cow health records, the magnitudes and dynamics of glucose and energy balances of dairy cows kept on an experimental farm were evaluated in the weeks before, of, and after a production disease was diagnosed. Because dry matter intake (DMI) decreased during the ...
Aufsatz
Improving Prospective Teachers’ Beliefs About a Double Discontinuity Between School Mathematics and University Mathematics
(2022-05-12)
Prospective teachers often perceive a “double discontinuity” between school mathematics and university mathematics. The first discontinuity can be described as the belief that there is no coherence between school mathematics and university mathematics, which forms part of the notoriously problematic transition from school to university. The second discontinuity can be described as a belief about the lack of relevance of university mathematics for the later professional practice of prospective teachers. Beliefs about ...
Aufsatz
Tailoring flow behavior and heat transfer in tempering channels for high-pressure die casting—analysis of potentials of commercial static mixers and prospects of additive manufacturing
(2023-02-16)
Additive manufacturing (AM) opens up manifold possibilities to influence the heat transfer between fluid and die in high-pressure die casting (HPDC), eventually allowing to minimize the total cycle time of the process. AM already has been exploited to establish near-contour temperature control systems in industrial applications. However, AM not only allows to influence the position of tempering channels in dies but it also allows to influence the fluid dynamics itself, e.g., by imprinted static mixers. Up to now, ...
Aufsatz
Numerical simulation of viscoelastic fluid-structure interaction benchmarks and their application to the human eye
(2022-10-11)
We present a numerical solution method for time-dependent viscoelastic fluid–structure interaction employing the arbitrary Lagrangian Eulerian framework. The derived monolithic variational formulation is discretized in time using the shifted Crank–Nicolson scheme and in space using the finite element method. For the linearisation we employ Newton’s method with exact Jacobians. The viscoelastic fluid is modelled either using the Oldroyd-B or a Burgers-type model. The elastic structures are non-linear hyperelastic ...
Aufsatz
Weathering of a Polyurethane-Based Gel Electrolyte
(2023-03-14)
A recently described flexible polyurethane electrolyte was artificially weathered at 25/50 °C and 50% r.h. in air and at 25 °C in a dry nitrogen atmosphere, each with and without UV irradiation. Different formulations and the polymer matrix, used as a reference, were weathered in order to investigate the influence of the amount of conductive lithium salt and the solvent propylene carbonate. The complete loss of the solvent at a standard climate was already observed after a few days, strongly influencing the ...
Aufsatz
Effects of changing water availability on land use in irrigated mountain oases of Al Jabal Al Akhdar, northern Oman
(2014)
In Oman, during the last three decades, agricultural water use and groundwater extraction has dramatically increased to meet the needs of a rapidly growing population and major changes in lifestyle. This has triggered agricultural land-use changes which have been poorly investigated. In view of this our study aimed at analysing patterns of shortterm land-use changes (2007-2009) in the five irrigated mountain oases of Ash Sharayjah, Al’Ayn, Al’Aqr, Qasha’ and Masayrat ar Ruwajah situated in the northern Oman Hajar ...