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Setup and operation of emergency care centres (sometimes also addressed as emergency reception centres) are part of emergency response in the environs of nuclear power plants. The preparation of an exercise scenario for such a centre is very demanding on the responsible agency. Therefore, a computer code has been developed which helps to translate the exercise objectives into instructions for figurants which simulate the affected population. These instructions are intended to steer a determined flow of people through the emergency care centre by providing fictitious radiological readings and by injecting the demand for additional actions of response personnel by statements and questions.

Due to high safety standards at nuclear power plants, no experience exits with nuclear emergencies in Western Europe. Thus, emergency exercises are the only possibility to assure effective protective measures should the very unlikely severe accident occur. The main objectives of exercises are generally the check of response plans for suitability, the test of the equipment's applicability and training of personnel for the unusual task to manage a nuclear emergency. After an introduction into the different types of exercises, this contribution focuses on off-site nuclear emergency exercises, explaining frame conditions to ensure good practice and, finally, reports some experience from exercises.

Off-site nuclear emergency response in Germany is divided into disaster response under the responsibility of the Länder and measures for precautionary radiation protection pursuant to the Precautionary Radiation Protection Act under the lead of federal authorities. Early countermeasures at the regional level require a different management than long-term and comprehensive actions of precautionary radiation protection. As situations may arise in which measures of both approaches overlap with regard to place and time, it is essential to make thorough preparations in order to avoid problems with implementation.

A static analysis of measurements of $^{12}\mathrm{C}$ elastic electron-scattering cross sections demonstrates unambiguously the existence of a form-factor energy dependence beyond that due to Coulomb distortion effects. This energy dependence increases smoothly as a function of momentum transfer and incident energy in the region covered by the experiments (1.0${\mathit{q}}_{\mathrm{eff}}$2.3 ${\mathrm{fm}}^{\mathrm{\ensuremath{-}}1}$, 240${\mathit{E}}_{0}$690 MeV). Outside the first diffraction minimum the discrepancies between the form factors deduced from data obtained at different energies are as large as 5%; in the minimum discrepancies as large as 18% have been observed. Including dispersion corrections which are reasonably compatible with this observed energy dependence in the analysis of the data increases the rms charge radius deduced for $^{12}\mathrm{C}$ by 0.007 to 2.478(9), fm, which is in excellent agreement with the value from muonic x-ray studies.

Urgent protective measures for the possibly affected population in the pre-release and release phase of a nuclear accident are decided upon and implemented by civil protection authorities on regional and local level. The responsible officers of these authorities are experienced in emergency response, but not in radiological questions. Their radiological advisors, on the other hand, mostly coming from surveillance agencies, often lack knowledge about conditions framing practical response measures. Moreover, although the scientific basis of protective measures is unquestionable, implementation policies are widely different in different countries and render co-ordination of response in border areas difficult. Finally, decreasing availability of funds sharpens the already existing problems due to diminishing interest of young scientists in radiation protection. Measures to improve upon the situation and prerequisite conditions will be discussed.

The transition densities of the 0 + → 2 1 + and 0 + → 2 2 + transitions in 34 S have been determined by an inelastic electron-scattering experiment covering a momentum transfer range 0.5 fm −1 q −1 . The cross sections were analysed model-independently by a Fourier-Bessel expansion. The resulting B (E2) values are in good agreement with adopted values from previous experiments. The deduced transition radii follow the systematics of E2 transitions. Shell-model calculations predict the form factor of the first 2 + state reasonably while they do not give the correct position of the diffraction minimum for the 2 2 + state.

Elastic electron scattering has been used to determine the transverse form factor of the /sup 17/O ground state in the effective momentum-transfer range 0.55 < or = q/sub epsilon/ < or = 2.8 fm/sup -1/. The data show considerable deviation from single-particle predictions; in particular, a sizable suppression of the M3 and an enhancement of the high-q side of the M5. Recent shell-model, core-polarization, and meson-exchange calculations are not adequate to explain these effects.

The charge form factors of 17O and 18O have been measured by electron scattering, and the charge-distribution differences between these nuclei and 16O have been extracted. The spherical part of the 17O distribution is very close to that of 16O while the 18O distribution is substantially different.

Our investigation of the energy dependence of dispersive effects in elastic electron scattering from {sup 12}C has been extended to a beam energy of 690 MeV. The cross section observed in the minimum of the form factor is larger than that predicted using a static charge density obtained by fitting lower-energy data with the customary phase-shift analysis. This filling-in'' of the minimum at 690 MeV is even larger than that observed previously at 430 MeV. This indicates an increase in the relative strength of higher-order processes in the minimum with an increase of beam energy; the presence of dispersive effects is the most likely explanation for this effect.

Inelastic electron scattering with high energy resolution (FWHM = 30 keV) has been used to study the states at 6.05(0 + ), 6.13(3 − )and 6.92(2 + ) MeV excitation energy in 16 O for momentum transfers q =0.22–0.49 fm −1 . The experiment yields a new determination of reduced transition probabilities and radiative widths for ground-state transitions.

Elastic electron scattering cross sections for the nucleus $^{12}\mathrm{C}$ have been measured in a momentum transfer range from 0.25 to 2.75 ${\mathrm{fm}}^{\ensuremath{-}1}$. The data were analyzed in a model independent way with a Fourier-Bessel parametrization of the charge distribution. For the rms radius, the value ${〈{r}^{2}〉}^{\frac{1}{2}}=(2.464\ifmmode\pm\else\textpm\fi{}0.012)$ fm (no dispersion corrections applied) has been obtained, and agrees with those of other electron scattering experiments and with muonic atom experiments, but disagrees with data obtained from measurements of muonic x-ray transitions with a crystal spectrometer which show a larger rms radius. The extracted distribution disagrees with Hartree-Fock calculations in both the radial dependence and the rms radius. The behavior of the form factor in the diffraction minimum was investigated in detail. The experimentally determined cross sections in the minimum are always larger than those obtained from the Fourier-Bessel analysis. These deviations amounted to 5% for a primary energy of 320 MeV and to 2% for 240 MeV and may be interpreted as an indication of dispersion effects.NUCLEAR REACTIONS $^{12}\mathrm{C}$; absolute ($e, e$) cross sections measured. Charge distribution and rms radius deduced. Discussion of dispersion effects, comparison with HF calculations.

A significant energy dependence was observed in the region of the first diffraction minimum of the form factor for elastic electron scattering from /sup 12/C between 238 and 419 (and 431) MeV. This effect might be attributed to dispersive (two-step) processes.

The multichannel detector system of the energy-loss electron scattering facility at the Darmstadt linear accelerator is described. The system consists of 36 overlapping plastic scintillators backed up by a large Cerenkov counter. Fast logic circuitry (300 MHz) is used to form a pattern of coincidence and anticoincidence bins defining 69 momentum channels. Each channel has a momentum acceptance of Δp / p = 3 × 10 −4 . The over all energy resolution in the electron scattering spectra is ΔE ≈ 30 keV (fwhm) taken with the targets of typical thickness of about px = 20 mg/cm 2 and is largely independent of bombarding energy. Examples of electron scattering spectra from 14 N, 16 O, 40 Ca and 208 Pb are presented. The complete system has worked successfully first in the summer of 1974 and has since been in operation continously without major breakdown.

Elastic electron scattering experiments on the isotopes 32,34,36 S were performed covering a range in momentum transfer q = 0.5−2.6 fm − . The cross sections were analysed with the Fourier-Bessel method yielding model-independent charge distributions and their differences. The extracted rms radii follow approximately the systematics of even-even nuclei; this also holds for the gross features as expressed in dms radii and skin thicknesses.

Inelastic electron scattering from the low-lying even-parity states of $^{18}\mathrm{O}$ has been performed. The measurements span a range in momentum transfer from 0.6 to 2.7 ${\mathrm{fm}}^{\ensuremath{-}1}$. Form factors have been determined for the two lowest ${0}^{+}$ excitations, the three lowest ${2}^{+}$ excitations, and the three lowest ${4}^{+}$ excitations. Transition densities for the ${2}^{+}$ and ${4}^{+}$ excitations have been obtained from a Fourier-Bessel analysis of these data. Comparisons were made with the predictions of various theoretical calculations and the agreement was found generally to be poor. A coexistence model was used to decompose the measured form factors into their single-particle and collective components, which in turn were compared with their counterparts in $^{16}\mathrm{O}$ and $^{17}\mathrm{O}$. The results indicate that this model provides a useful framework within which to understand the structure of the oxygen isotopes. Transition densities also were obtained within the context of this model.NUCLEAR REACTIONS $^{18}\mathrm{O}$($e$,${e}^{\ensuremath{'}}$) low-lying even-parity excited states; measured form factors at 90\ifmmode^\circ\else\textdegree\fi{} and 160\ifmmode^\circ\else\textdegree\fi{}, $0.6\ensuremath{\le}q\ensuremath{\le}2.7$ ${\mathrm{fm}}^{\ensuremath{-}1}$; comparison to shell and coexistence models; transition densities extracted.

A precise elastic electron scattering experiment on 48 Ca relative to 40 Ca, covering a range in momentum transfer from 0.3 to 3.5 fm −1 , is presented. The charge distribution of 48 Ca and the charge difference distribution with respect to 40 Ca is deduced. Results from proton scattering experiments are used to evaluate the neutron distributions. The experimental findings are compared to former measurements and to HF-calculations. Preliminary results of measurements on the even Germanium-Isotopes are discussed.

The isospin-forbidden electroexcitation of the 1−, T = 0 state at 7.12 MeV in 16O has been studied for momentum transfers q = 0.22 − 0.49 fm−1. The form factor at these momentum transfers is determined by the sum of the isospin T = 0 part and a T = 1 contribution. A single particle-hole harmonic oscillator shell model calculation reproduces the q-dependence of the measured form factor which shows that the isovector contribution interferes destructively with the isoscalar part and has a strength of about 2% of the T = 0 amplitude.

The recession experienced by the tungsten industry all over the world in 1982 continued and worsened further in 1983. The sharp decline in demand and the dramatic price decreases that started in 1982 continued into 1983 and resulted in the production curtailment or shutdown of over one-third of the world mine capacity. However, a healthy recovery in demand is expected in 1984.

A simple model for nuclear surface vibrations in permanently deformed nuclei does well in reproducing electron scattering cross sections of rotational levels built on a K/sup ..pi../= 0/sup -/ intrinsic octupole vibration in /sup 238/U.

Materials are surveyed which meet the exacting demands of builders of high performance road cars and racing cars. Aluminum, magnesium, and alloy steel are the most commonly used materials. Aluminum, with its light weight, high strength-to-weight ratio, and ease of fabrication, is used for engine blocks, transmission and differential housings, body sheet, and numerous other applications. Magnesium, a low-density and relatively durable metal, has found application in crankcases, transmission cases, and wheels for vehicles primarily driven in competition. Components in high performance cars where stresses can only be met by high-strength steels, either simple cast irons or nickel superalloys, include crankshafts, camshafts, connecting rods, exhaust manifolds, valves, turbocharger housings, and suspension components. More exotic materials such as titanium, plastics, and composites have also found use. Porsche has employed titanium connecting rods in its Type 917, 930, and 935 sports cars, titanium rear half-shafts and coil springs in its Type 935 racing Turbo-Carrera. Glass fiber reinforced plastics are extremely attractive materials for high performance cars because they are light, have good strength, and are easy to repair at trackside. The bodywork for competition cars, except those derived from a series-production car, is made of glass-reinforced plastic; this material is also used for air ducts, aerodynamic spoilers, engine fans, and door panels, and for body shells of production sports cars such as the Corvette, Avanti, and Lotus.

There has never been anything like it. Hardly a week passes when the daily press doesn't feature an article on superconductivity. Already, utopian visions of magnetically levitated trains, desktop supercomputers and other devices straight out of "2001" are doled out almost daily. Yet less than a year ago, the word "superconductivity" was relegated to a few esoteric journals found in university libraries. The discovery of the ceramic (oxide) superconductors (yttrium-bariumcopper oxide) is already likened to such milestones as the lightbulb and the transistor. While the new superconductors may some day have far reaching consequences, it may be just a bit premature to make such comparisons. For Japan, however, 2001 may come sooner than anyone has imagined. Frequent press reports point out the seriousness of the Japanese superconductor effort. It is no secret that Japan wants to beat the West in commercializing superconductivity technology. The almost lightning-like speed with which their superconductivity research consortium was formed was somewhat overwhelming. From the U.S. perspective, Japan's determination is frightening, but worthy of much admiration. Hopefully, the current U.S. administration's "Superconductor Initiative" will provide the necessary incentive to build on this new discovery, moving it to commercialization. The discoveries of the new superconductors are considered so fundamental and their potential economic impact so great that President Reagan has ordered the government to implement a coordinated national effort to capitalize on the new discoveries. Nevertheless, a headline in the Wall Street Journal on May 5, 1987, cautioned that "enthusiasm over superconductors is tempered by daunting problem." The article points out, and rightly so, that two significant obstacles must be overcome before the new materials can become commercial reality. These obstacles are fabricability and current-carrying capacity. This advisory was expressed once again in a September 11th article in the same publication. Less than ten years ago, the superconductor industry was a stable, ifnot spectacular, enterprise with prospects of moderate growth. However, as of early 1987, much of this has changed with the discovery of the oxide-based superconductors that show promise of operating at considerably higher temperatures than the liquid-heliumcooled metallic superconductors. At the time of this writing (fall 1987), the superconductivity industry was poised on the brink of a technological revolution as a result of the discovery of a new type of high-temperature superconducting materials. While the predictions suggest a bright future, much will depend on the development of suitable, economic fabrication technologies. . There is every indication that the microelectronic industry will be the first to make use of the high-temperature superconductors in some sort of semiconductor/superconductor hybrid device.