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Improvements of car safety focused first on frontal, then on side protection during the 90's. The ongoing next step is rollover protection. Existing hardware like seat belts with pretensioners and side airbags are able to protect vehicle occupants in rollover crashes as well. In the future some enhanced protection equipment will supplement these protection systems.For the integration of rollover protection into a vehicle safety system, the trigger philosophy is a key point. Full-scale rollover crash tests give basic information about how sensors and algorithms trigger the relevant protection devices. Several test procedures are established and in use. The FMVSS-208 rollover procedure is supplemented by some other tests like corkscrew, embankment, curb trip and sandpit rollover.The article gives an overview of rollover tests conducted by DEKRA by request of OEMs and suppliers. Purposes, advantages and disadvantages of the tests are being discussed.Additional real-world accident example and statistics are included. Information about rollover protection hardware and trigger strategies will be presented.

The separation and recovery of volatile hydrocarbon vapors from gasoline tank farm off-gases can in Europe be considered to be a state-of-the-art technology (1). A new application in the treatment of gasoline vapors is the installation of a membrane module in vapor return lines from petrol dispensers to storage tanks at gasoline stations to enhance the vapor recovery efficiency of this system. For solvent vapor recovery, some membrane systems have been installed in the chemical and pharmaceutical industry (2). This paper deals with design features and operating experience.

The aim of this article is to show the importance of concentration polarization effects in the separation of gas–vapor mixtures using membranes. In the experimental part of this work, gas mixture measurements are conducted with a specially designed test cell. The experimental data are analyzed using a two-resistance model for the transport through the membrane, which is derived in the theoretical part of this work. The two resistances considered are the transport through the boundary layer on the feed side of the membrane and through the separation layer. For the transport through the separation layer an extended free volume model is derived. This model considers not only the feed side but also the influence of the permeate side on the separation properties of the membrane. The results of the measurements show the influence of concentration polarization effects and their dependencies on feed pressure, membrane thickness, and feed flow rate.

We report here the biologically active conformation of acetylcholine when bound to the high-affinity state of the receptor from Torpedo californica. The acetylcholine conformation was determined in the free and bound states by proton NMR two-dimensional nuclear Overhauser effects. In agreement with x-ray crystallographic data, acetylcholine in solution has an extended conformation with an average distance between the acetyl methyl and choline methyl protons of approximately equal to 5 A. When bound to the acetylcholine receptor, acetylcholine adopts a conformation where the acetyl methyl group is close (3.3 A) to the methyl groups of the choline moiety. This bent conformation places the oxygens adjacent to one another and allows the methyl groups to form an uninterrupted hydrophobic surface over the rest of the acetylcholine molecule. The significant difference between the free- and bound-state conformations implies that structure-activity studies based solely on molecular modeling strategies must be approached with caution.

Many industrial processes which handle volatile hydrocarbons produce organic vapors. These vapors which are generated during storage, trans- portation and the handling of hydrocarbons cause environmental problems. The contaminants dispersed in the air are contributing factors to the development of photochemical smog. In addition they represent valuable resources which should be recovered, GKSS has developed a membrane and a membrane process for the recovery of off gases from gasoline storage and handling [1, 2]. A 300 m3/h vapor recovery unit for the treatment of off gases from a gasoline tank farm started operation in October 1989.

The paper deals with engineering aspects of the design of membrane systems for the separation and recovery of volatile hydrocarbons from off-gases. The membrane which is used for this application is a thin film composite membrane with an elastomeric selective top layer. This membrane has a high permeability for various hydrocarbon vapors and a low permeability for oxygen and nitrogen. The membrane configuration is a flat sheet membrane manufactured to an envelope with a round shape which is installed in the so-called GS module. The energy impact in accordance with the condensation mode and operating pressures is shown. Case studies on the influence of different process parameters, e.g., plant capacity, recovery rate, pressure ratio, stage cut and retentate concentration were carried out on the basis of given feed compressor and vacuum pump capacities. Finally, the investment costs of vapor recovery units in gasoline tank farms are discussed.

The effect of the timing of treatment with the ATP-regulated potassium channel agonist BMS-180448 was evaluated in isolated rat heart and ferret models of ischemia and reperfusion. In rat hearts, 10 microM BMS-180448, given before and after global ischemia as well as only during reflow, improved reperfusion contractile function and attenuated lactic dehydrogenase release, although reperfusion-only treatment was less effective. Cromakalim (10 microM) and bimakalim (10 microM) treatment before and after global ischemia afforded a degree of protection similar to that of BMS-180448, although they were not cardioprotective when given only during reperfusion. Pre- and post-treatment cardioprotection were abolished by glyburide. Ischemia/reperfusion significantly increased cytosolic calcium concentration ([Ca++]i) and BMS-180448 given only during reperfusion attenuated this change. In anesthetized ferrets, BMS-180448 (2 mg/kg) or vehicle was infused i.v. during a 40-min interval beginning 1) 10 min before coronary occlusion, 2) at the 45th min of ischemia or 3) at the 5th min of reperfusion. Preocclusion administration of BMS-180448 was associated with a 35% reduction in infarct damage from that recorded in vehicle-treated control ferrets. Drug administered at the midpoint of ischemia reduced infarct size approximately 44%, whereas delaying BMS-180448 infusion until the 5th min of reperfusion reduced, but still provided a significant (17%) level of salvage. The favorable effects of BMS-180448 in the ferret were not associated with changes in either collateral blood flow or peripheral hemodynamics. Thus BMS-180448 shows some protective effects when given only during reperfusion. Cromakalim and bimakalim did not exert similar actions and the difference may be secondary to the faster penetration of BMS-180448.