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Aufsatz
Accurate Hartree-Fock-Slater calculations on small diatomic molecules with the finite-element method
(1988)
We report on the self-consistent field solution of the Hartree-Fock-Slater equations using the finite-element method for the three small diatomic molecules N_2, BH and CO as examples. The quality of the results is not only better by two orders of magnitude than the fully numerical finite difference method of Laaksonen et al. but the method also requires a smaller number of grid points.
Aufsatz
Solution of the time dependent Dirac-Fock-Slater equation for many-electron collisions systems using a time window method
(1994)
We present a new scheme to solve the time dependent Dirac-Fock-Slater equation (TDDFS) for heavy many electron ion-atom collision systems. Up to now time independent self consistent molecular orbitals have been used to expand the time dependent wavefunction and rather complicated potential coupling matrix elements have been neglected. Our idea is to
minimize the potential coupling by using the time dependent electronic density to generate molecular basis functions. We present the first results for 16 MeV S{^16+} on Ar.
Aufsatz
Ground state correlation energy of the Be-sequence for Z = 4-20 in MCDF approximation
(1989)
The ground state (J = 0) electronic correlation energy of the 4-electron Be-sequence is calculated in the Multi-Configuration Dirac-Fock approximation for Z = 4-20. The 4 electrons were distributed over the configurations arising from the 1s, 2s, 2p, 3s, 3p and 3d orbitals. Theoretical values obtained here are in good agreement with experimental correlation energies.
Aufsatz
Self-energy corrections in heavy muonic atoms
(1978)
Self-energy corrections for ls_1/2 levels of heavy muonic atoms are calculated to all orders in the external field using numerical techniques to evaluate the bound-muon propagator. The resulting values of the selfenergy are about 10% larger than previous estimates.
Dissertation
Untersuchungen zum Leistungspotenzial des Einsatzes von Arbeitspferden und moderner pferdegezogener Technik im Ökologischen Landbau am Beispiel der Mahd im Grünland
(2017-06-13)
Während der landwirtschaftliche Einsatz von Zugtieren im weltweiten Maßstab nach wie vor eine erhebliche Rolle spielt, wurden die Zugtiere in Deutschland in den 1950er und 1960er Jahren nahezu vollständig vom Schlepper verdrängt. Mit Beginn der 1990er Jahre ist eine langsame Zunahme des
Einsatzes von Arbeitspferden vor allem im Ökologischen Landbau zu beobachten. Aussagekräftige Daten zu Leistungsfähigkeit und Einsatzvoraussetzungen moderner Pferdetechnik fehlen bisher weitgehend, sind jedoch Voraussetzung sowohl ...
Dissertation
Diversity, local uses and availability of medicinal plants and wild yams in the Mahafaly region of south-western Madagascar
(2015-08-31)
Short summary:
This study was undertaken to assess the diversity of plant resources utilized by the local population in south-western Madagascar, the social, ecological and biophysical conditions that drive their uses and availability, and possible alternative strategies for their sustainable use in the region. The study region, ‘Mahafaly region’, located in south-western Madagascar, is one of the country’s most economically, educationally and climatically disadvantaged regions. With an arid steppe climate, the ...
Dissertation
Microbial response to restoration of tantalite mine soils in western Rwanda
(2016-05-04)
Artisanal columbite-tantalite (coltan) mining has had negative effects on the rural economy in the great Lakes region of Africa through labor deficits, degradation and loss of farmland, food insecurity, high cost of living, and reduced traditional export crop production alongside secondary impacts that remotely affect the quality of air, water, soil, plants, animals, and human wellbeing. The situation is multifaceted and calls for a holistic approach for short and long-term mitigation of such negative effects. This ...
Dissertation
Diversity and nutritional properties of Pakistani dates: implications for sustainable value chain and decent living perspectives of rural households
(2016-02-09)
Date palm (Phoenix dactylifera L.) occupies almost three percent of the total worldwide cultivated area, with an annual production of seven million tonnes (t). Pakistan is an ideal place for the cultivation of date palm due to its sandy loam soil and semi-arid climate. In 2012, Pakistan produced 600,000 t of dates, on an area of 95,000 ha. Baluchistan province is the country’s top date producer, followed by Sindh, Punjab and Khyber Pakhtunkhwa (KPK) provinces. More than 300 date varieties are known to exist in Pakistan ...