We present new ASCA observations covering the 0.5-10 keV X-ray range of the cooling neutron star candidates PSR 0656ϩ14 and PSR 1055Ϫ52. Previous ROSAT observations had shown that two-component models, either two blackbodies or a blackbody plus a power-law, provided the best spectral fits to their X-ray emission. The combined ASCA and ROSAT spectrum of PSR 0656ϩ14 reveals two blackbody components with T 2 8 ϫ 10 5 K and T 2 1.5 ϫ 10 6 K and shows evidence that a power-law component is needed to account for higher energy photons. This three-component fit gives a reduced 2 that is half the value of a more conventional two component fit (1.3 as compared to 2.4). The fit to the combined spectrum for PSR 1055Ϫ52 yields a two-blackbody fit with T 2 8 ϫ 10 5 K and T 2 3.7 ϫ 10 6 K. Our results favor the existence of a hot polar cap in each of these pulsars with the ratio of the polar cap area to the neutron star surface area being 7 ϫ 10 Ϫ3 and 3 ϫ 10 Ϫ5 for PSR 0656ϩ14 and PSR 1055Ϫ52, respectively. The results are compared to models that make predictions of polar cap heating processes.

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An experimental study of single-particle crushing at slow compression rate was carried out for two kinds of glassy and five kinds of natural materials. The specimens were almost spherical particles of0.5 to 3.0 em in diameter.The relationships between particle size and fracture energy (strain energy) were calculated by using the results of the size effect ranging from about 10 em to 0. 0030 em of single particle crushing, as shown in the previous papers. The experimental results are summarized as follows:1) The fracture energies obtained were larger than the values calculated from the theoretical equations for limestone, marble and gypsum.2) For natural materials, the specific fracture energies rapidly increased with decreasing particle size within the range of particle size smaller than about 500 f.J.m.

In clinical settings, false-positive results are treated as positive until bacterial identification. It may result in the discarding of blood products in blood centers or affect clinical decisions in hospitals or testing facilities. Moreover, the management of these samples is usually time- and labor-consuming. The results of our study may help clinicians and laboratory staff in making a more precise evaluation of positive reactions in BacT/Alert.

A b.st ra c tWe have been developing a Compton scattering type polarimeter which consists of nine unit counters to detect the polarization of hard X-rays from stellar objects such as the Crab Nebula. We constructed one unit counter which consists of one plastic scintillator(7x7x5cm3) and four phoswich scintillators(6.7xl.1x32.2cm3) made of NaI(TI)+CsI(Na). The characteristics of the unit counter were measured in detail to determine the detection efficiency (20.3%) and the modulation factor (27.5%) at 53.4keV. The background spectrum of the unit counter in the laboratory is also measured. Based on the results, the background from the outside of the active collimator is reduced by 50.5% when used with the PSD. On the basis of these results, the performance of the planned polarimeter was estimated by computer simulations. The results showed that the polarimeter can detect the polarization of hard X--rays from the Crab Nebula at a MDP (Minimum Detechble Polarization) of 14.0% with a 3-hour balloon observation.