TY - JOUR A1 - Hardt, Arno A1 - Martin, S. A1 - Meißburger, J. A1 - Retz, R. A1 - Wimmer, J. T1 - The cryopump system of the QQDDQ magnet spectrometer BIG KARL JF - Vacuum N2 - Cryopumps without liquid nitrogen shielding are used to provide a vacuum of 10−6 torr in the spectrometer. The vacuum system is subdivided in three sections that can be separated by valves. The first section (scattering chamber) has a volume of 60 l, two rotation transmissions with 35 cm dia and a sliding seal that allows a rotation of 160° without deteriorating the vacuum. The second section includes the vacuum chambers inside the magnets with 6 × 80 cm cross-section and a length of 1200 cm. The third section (detector box) has a volume of 4300 l and contains a moveable detector system. The gas inside the detector with a pressure of 760 torr is separated from the vacuum by a 15 μm mylar foil with an area of 300 cm2. The detector box can be valved off by a valve with the dimension of 10 × 100 cm. The layout of system is given. The instrumentation and the interlock system are described. First experiences with this system are presented. Y1 - 1978 U6 - http://dx.doi.org/10.1016/S0042-207X(78)80026-8 SN - 1879-2715 (E-Journal); 0042-207X (Print) VL - 28 IS - 10-11 SP - 483 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Helsper, Christoph A1 - Fissan, H. J. A1 - Franzen, H. ED - Benarie, Michel M. T1 - Particle Size Distributions of Combustion Aerosols T2 - Atmospheric Pollution 1978 : Proceedings of the 13th International Colloquium; 25-28 April 1978; Paris, France; Edited by Michel M. Benarie N2 - It has been observed that carcinogenic polycyclic aromatic hydrocarbons (PAH) are present in the atmosphere. Combustion processes are considered the most important sources for PAH. Among these, the burning of coal produces the highest emission, but in cities with high traffic density and low meteorological exchange activities, vehicle emissions determine the immission situation, especially in narrow streets. For estimating the potential health effects caused by PAH, it is sufficient to characterize the emission of PAH with respect to their physical state, concentrations, and, as far as the particulate phase is concerned, size distribution. The size distribution is important for transport phenomena, inhalation, and deposition in the respiratory tract. These parameters mainly depend on the combustion system, on system operating conditions, on the exhaust system, and on exhaust cooling conditions. At exhaust-gas temperatures in the range of ambient air temperatures, almost the whole emission of PAH is made up of particulate matter. Y1 - 1978 SN - 0-444-41691-9 U6 - http://dx.doi.org/10.1016/S0166-1116(08)71583-8 SP - 263 EP - 266 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Meißen, Ralf A1 - Krischer, C. T1 - Elektronische Fernsehlesehilfe für hochgradig sehbehinderte JF - Biomedical Engineering / Biomedizinische Technik Y1 - 1978 U6 - http://dx.doi.org/10.1515/bmte.1978.23.s1.220 VL - 23 IS - s1 SP - 220 EP - 221 PB - De Gruyter CY - Berlin ER -