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The HELIOS experiment has measured inclusivep⊥ spectra of negative particles in the rapidity region 1.0⊥ spectra in p +W, O+W and S+W is similar, but cannot be described by a single exponential. Compared to p+p collisions, an excess is observed for low and highp⊥. This effect increases with the projectile mass. Except for very lowE⊥, the average transverse momentum ⊥> is found to be approximately constant up to the highest accessible values ofE⊥.

Transverse-energy distributions have been measured in the pseudorapidity region -0.1lab<2.9 for oxygen-nucleus collisions at incident energies of 60 and 200 GeV per nucleon for Al, Ag, and W target nuclei. The cross-section for the heaviest target nuclei at the highest incident energy is measured over 5 orders of magnitude and out to a maximumET of 200 GeV. Measurements of the differential densitydET/d?lab as a function of?lab are presented. In the pseudorapidity region -0.1lab<2.9 the transverse energy for an average central collision is proportional to ˜A0.5, while the fraction of the total transverse energy measured in an extended region of?lab>2.9 decreases with increasingA. The distributions are compared with the predictions of a dual parton model. Finally the question of the energy density is addressed.

Transverse-energy distributions have been measured in the pseudo-rapidity region -0.1 >?lab <2.9 for oxygen-nucleus collisions of incident energies of 60 and 200 GeV per nucleon for Al, Ag, and W target nuclei. We present a summary of the results and a comparison to theoretical model descriptions.

The biodegradation of 14C-labeled poly(ethylene-co-vinyl alcohol) (EVOH), 14C-labeled LDPE mixed with starch and a metal salt and 14C-labeled LDPE was studied. A comparison was made between samples exposed to UVirradiation for 60 h before inoculation and those that were not pre-aged. The samples were inoculated with a mixture of Penicillium simplicissimum and Fusarium redolens. The amount of evolved 14CO2 was measured by liquid scintillation counting (LSC). The changes in molar mass, crystallinity and amount of carbonyls were determined. After 498 days the pre-aged EVOH samples exposed to the fungi had the largest amount of evolved 14CO2. Pure LDPE was the least degraded of the three materials compared. The EVOH samples did not, however, show any changes in molar mass, crystallinity or number of functional groups as compared to an unaged sample. The pure LDPE and LDPE/MB samples showed a difference between the pre-aged samples and the non pre-aged samples. A small increase in number average molar mass (M¯n) was seen for the inoculated samples as compared to the sterile samples, indicating that the low molar mass part of the polymer had been assimilated by microorganisms.

Abstract: The results of a one-year study of the total air-borne14C effluents from two Swedish light-water reactors, one boiling water reactor (BWR) at Forsmark and one pressurized water reactor (PWR) at Ringhals, are presented. Air emitted from the stacks has been collected continuously over two-week periods and the14C content in the samples has been analysed using accelerator mass spectrometry (AMS). The14C activity concentration in the air issuing from the stack of the PWR varied between 2 and 1132 Bq/m3 with a mean value of 200 Bq/m3, while from the BWR the activity concentration varied between 4 and 146 Bq/m3, with a mean value of 95 Bq/m3. The corresponding14C release rate was 0.27 TBq/GWel·year for the PWR and 0.48 TBq/GWel·year for the BWR. During the same period of time, for comparison, the14C activity in continuously collected air from the stack of the PWR was also measured by liquid scintillation counting. In most cases the results of these measurements were in fair agreement with the corresponding AMS results.

A miniaturized earborne sound level duration time meter is described which utilizes photographic film as the storage element. It measures the time during which the sound pressure has exceeded two preset levels. In addition it records the running time of the device. The running time can be preset to either one day or one week. The microphone is placed at the entrance of the ear to measure just the sound that might damage the ear. It has been possible to make the meter so small that it can be worn under ear muffs. The weight of the complete device is 15 gram.

The hearing thresholds of shipyard workers have been measured with a Békésy sweep audiometer. The number of employees at different workplaces is so large that it is possible to select groups of workers of specified ages who have been employed by the shipyard for many years. These workers have used either earplugs of earmuffs for 5-10 years and have also been working all the time in almost the same noise environment. Three ways of investigation have been used to observe differences in the hearing levels between 'plug-men' and 'muff-men'. All three show a greater hearing impairment for 'muff-men' than for 'plug-men'. Under certain conditions earplugs provide the most effective protection although the attenuation is higher for earmuffs than for earplugs.

The64Ni(p, ?)65Cu reaction has been studied in the proton energy rangeEp=2.05–2.55 MeV. The gamma-ray spectra were recorded with a three-crystal pair spectrometer at proton energy differences of 19 keV covering the proton energy range. An average gamma-ray spectrum was formed by adding all the individual spectra after proper adjustment as a result of the alterations in proton energy. The intensities of the gamma rays to final states with knownJp-values were tested against theoretical calculations based on the Hauser-Feshbach theory. The gamma-ray strength function for energies lower than 9 MeV has been extracted from the experiment.

The yield curve for the54Fe(p, γ)55Co reaction in the energy regionEp=1.5–2.9 MeV has been recorded and the decay of ten resonances has been investigated. For six of the resonances the strengths have been determined. The angular distributions of the gamma rays have been recorded for four resonances to obtain spins or spin limitations for excited levels. In addition the lifetimes of 10 bound levels were determined with the Doppler Shift Attenuation Method. The isobaric analogues of the ground state and five excited states in55Fe are discussed.

The59Co(p, γ)60Ni reaction has been investigated in the proton energy regionEp=1365–2150 keV. Decay schemes and branching ratios have been determined for ten resonances, five of which have been identified as possible analogues or fragments of analogues of the ground state (5+) and the 58.6 keV (2+), 277.1 keV (4+), 288.4 keV (3+), and 435.7 keV (5+) levels in60Co. At eight of the resonances most of the decay seems to go via a group of states with an excitation energy of 5–9 MeV. The investigated analogue states give a Coulomb displacement energy of 9118±7 keV.

The hearing thresholds of a total of 58 workers aged 20 to 65 years were measured annually over a period of 4 years using Békésy sweep-frequency audiometry. Using these data, accurate values of the yearly rate of change of hearing threshold level were calculated. The rate of change of hearing threshold level due to presbyacusis was obtained from several data sets, and the rate of change of hearing threshold level due to noise was calculated. When the average hearing threshold level over the frequency range 2-8 kHz was considered, it was found to be possible to establish a significant rate of threshold shift caused by exposure to noise for yearly changes as small as ∼ 2 dB. In the cases investigated about 30% of the ears showed a significant deterioration in hearing ability due to noise. When comparing the permanent threshold shift caused by noise in groups of younger and older workers, it was found that the younger workers exhibited less threshold shift than expected, whereas the older workers showed a greater threshold shift than expected.

A miniaturized earborne sound level duration time meter is described which utilizes photographic film as the storage element. It measures the time during which the sound pressure has exceeded two preset levels. In addition it records the running time of the device. The running time can be preset to either one day or one week. The microphone is placed at the entrance of the ear to measure just the sound that might damage the ear. It has been possible to make the meter so small that it can be worn under ear muffs. The weight of the complete device is 15 gram.

The hearing thresholds of a total of 58 workers aged 20 to 65 years were measured annually over a period of 4 years using Bekesy sweep-frequency audiometry. Using these data, accurate values of the yearly rate of change of hearing threshold level were calculated. The rate of change of hearing threshold level due to presbyacusis was obtained from several data sets, and the rate of change of hearing threshold level due to noise was calculated. When the average hearing threshold level over the frequency range 2-8 kHz was considered, it was found to be possible to establish a significant rate of threshold shift caused by exposure to noise for yearly changes as small as ∼ 2 dB. In the cases investigated about 30% of the ears showed a significant deterioration in hearing ability due to noise. When comparing the permanent threshold shift caused by noise in groups of younger and older workers, it was found that the younger workers exhibited less threshold shift than expected, whereas the older workers showed a greater threshold shift than expected.