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Notes: G-invariant metric compatible linear connections on homogeneous spaces G/H are investigated herein. For certain classes of homogeneous spaces the most general form of G-invariant metric and torsion are found.

Notes: A Geographical Information System (GIS) was combined with a model for simulating leaching and degradation of herbicides. The model uses first–order kinetics to simulate degradation, and a cascade model to simulate transport. This system was tested with data from a 16 km2 research catchment in northern Germany. Geometrical, topological, and soil data of this area were stored in a GIS. For the whole area, divided into small homogeneous sites (ecotopes), model runs were carried out. The system is able to handle data for all ecotopes automatically and to present calculated results on the behaviour of herbicides as distributed over time and depth for the area. An application of ethofumesate made in sugar–beet in spring and recropping of winter wheat after beet harvest was modelled. Degradation/sorption parameters were estimated from similar soils. Simulation results showed slower degradation in the sandy sites of the catchment, compared to the more loamy regions. Residues of herbicide remaining after beet harvest were greater than 20% of the applied dose in the sandy soils after 150 days. Hence, high risk of damage to the following crop of winter wheat was predicted. At the other sites residues remaining were between 2% and 20% of the applied dose. Einbindung eines Simulationsmodells zum Herbizidverhalten in ein Geographisches Informationssystem–Beispiel zur schlagspezifischen AnwendungEin Geographisches Informationssystem (GIS) wurde mit einem Simulationsmodell für Herbizidabbau und –einwaschung kombiniert. Grundlage der Abbausimulation ist eine Kinetik 1. Ordnung, der Transport im Boden wird mit Hilfe eines Kaskadenmodells berechnet. Das System wurde in einem Intensiv–Untersuchungsgebiet (16 km2) in Norddeutschland getestet. Geometrische und topologische Daten der Fläche sowie Bodendaten sind im GIS gespeichert. Für die gesamte Fläche, die in kleine homogene Teilflächen (Ökotope) aufgeteilt wurde, wurden Simulationsberechnungen durchgeführt. Das System ist in der Lage, Daten für alle Ökotope automatisch bereitzustellen und die Ergebnisse zum Einwaschungs– und Abbauverhalten für die gesamte Fläche in ihrer Verteilung über Zeit und Tiefe darzustellen. Als Szenario wurde die Applikation von Ethofumesat in Zuckerrüben im Frühjahr mit einem Nachbau von Winterweizen nach der Rübenemte gewählt. Abbauund Sorptionsparameter waren in ähnlichen Böden ermittelt worden. Die Simulationsergebnisse zeigten einen langsameren Abbau in den sandigen Böden verglichen mit den lehmigen. In den sandigen Böden lagen die Rückstandsgehalte nach 150 Tagen übe 20 % der Ausgangskonzentration, wodurch ein hohes Nachbaurisiko für Winterweizen prognostiziert wurde. Für den Rest der Fläche lagen die Rückstände zwischen 2% und 20% der Ausgangskonzentration.

Notes: Abstract Formalism for the electroproduction of strange particles based on the one photon exchange approximation and the Feynman diagrams representation of hadron current is reviewed. Different photoproduction models are compared with available photo and electroproduction data. New experiments are proposed that may resolve existing uncertainties and inconsistencies. The formation of hypernuclei via kaon electroproduction is investigated theoretically and compared with other reactions involving purely hadronic processes.

Notes: Abstract A detailed theoretical analysis of spin degrees of freedom in carbon isotopes is performed, probing them by electron scattering, pion photoproduction and radiative pion capture from the mesoatomic orbits.

Notes: Abstract It has long been recognized thatμLCR could profitably be done with the high intensity surface beam at LAMPF [1]. A spectrometer has been built that is matched to the LAMPF beam characteristics. The polarization information is obtained from a downstream array of counters while side counters, containing no polarization signal, monitor theμ + beam. Degraders select higher energy e+, thereby reducing rates and required counter segmentation while maintaining information content. We apply a ramped longitudinal field in addition to the static one to average over instabilities in theμ + beam. This field scan allows direct interpretation of data and does not require a prior estimate of the resonance structure of a sample. Flux coils monitor the applied ramp field and eddy-current induced fields. High average rate (2×107 μ +/s). good stability, and the versatile field scan permitted useful data to be collected from Cu, Al(Cu), Al, Si(Al), and polycrystalline Si targets.

Notes: 2 and CO2 concentrations in the system. Besides these biological processes, the contribution of physiochemical dissolution of produced CO2 in soil water to the pressure changes observed is to be considered. The method allows collection of additional information about the contribution of nitrification and denitrification to N2O emission from soil, provided simultaneous measurements of N2O emission are performed. Furthermore, BaPS can be used to quantify the percentage of N2O lost from nitrification. The advantage of BaPS is that disturbance of the soil system is minimized compared with other methods such as the use of gaseous inhibitors (e.g., acetylene) or application of 15N compounds to the soil. We present the theoretical considerations of BaPS, results for nitrification rates, denitrification rates, and identification of soil N2O sources in a well-aerated coniferous forest soil using BaPS. The suitability of BaPS as a method for determination of gross nitrification is demonstrated by validation experiments using the 15N-pool dilution technique.