[en] On July 25, 2006, a short circuit in the switchgear of the 400 kV high-voltage grid near Forsmark caused a failure of 2 out of 4 redundances of the emergency power system of Forsmark-1 within one minute. Immediately after the accident, only incomplete and partly contradictory information about the precise course of events and its causes was available. In the meantime, the complex pattern of events has been reconstructed in detail, resulting in a conclusive picture which differs in important respects from the descriptions in the media over the first few days. A chain of malfunctions is now becoming apparent as the cause of the partial failure of the emergency power supply system. (orig.)

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[en] The present paper gives a method to calculate the pressure waves which arise from a body penetrating into water. A model to determine the generation of the pressure wave during the penetration process of the body is developed, and the propagation of the wave is calculated. The results are applied to the crash of an airplane into the water in front of an intake structure leading to short and intense shocks to the building and its components. (orig.)

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[en] Whilst international safeguarding of fissile materials against abuse has been the subject of extensive debate, little public attention has so far been devoted to the internal security of these materials. All countries using nuclear energy for peaceful purposes have laid down appropriate regulations. In the Federal Republic of Germany safeguards are required, for instance, by the Atomic Energy Act, and are therefore a prerequisite for licensing. The aims and methods of national nuclear materials management are contrasted with viewpoints on international safeguards

[en] Whilst international safeguards of fissile materials to protect against abuse has long been the subject of extensive debate, little public attention has so far been devoted to the internal security of these materials. All countries using nuclear energy for peaceful purposes have corresponding rules and regulations. In the Federal Republic of Germany, for instance, this security is required also under the Atomic Energy Act and thus constitutes a licensing criterion. Internal security is distinguished from international safeguards also by the fact that actions of security forces are possible in cases of infringement, which means that much shorter detection times are necessary and appropriate while, on the other hand, the government proper and the organization operating the facility in question must be regarded as being above suspicion. International safeguards control, by contrast, is directed against governments as potential diverters of fissile material. (orig.)

[en] The scattering processes of slow electrons in high-resolution electron-energy-loss spectroscopy (HREELS) at the surface of organic solids have been studied, both theoretically and experimentally. We used selectively deuterated molecules which were prepared in highly ordered films by the Langmuir-Blodgett (LB) technique. In the framework of a microscopic approach the intensity ratios for CD- and CH-stretching vibrations in the dipolar and impact limit were estimated. The broad angular distribution of elastically reflected electrons scattered at organic surfaces as well as the anisotropy of the films were taken into account. In a first set of experiments the influence of the substitution of hydrogen by deuterium on the intensity of the corresponding methyl and methylene stretching vibrations was measured. Comparison of the results with the theoretical considerations supports a dipolar-dominated scattering at around 5 eV with an increase of the impact contribution at lower energies. Second, the information depth and its dependence on the impact energy of the electrons was studied. The strong increase in the information depth towards lower electron energies can be correlated with a decrease of the dipolar scattering intensity and an enhancement of short-range interaction. (orig.)