Vol.9,

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A Glauber multiple scattering theory in terms of partons and nucleons is applied to study productions of kaon, lambda and antilambda in 50 GeV proton-nuclcus scatterings at JHF (the Japan Hadron Facility). The ratios of the differential cross sections of nucleon-tungsten to nucleon-beryllium are calculated versus the transverse momentum at central rapidity. The cancellation between the single and double scattering amplitudes leads to nuclear enhancement of strangeness production at central rapidity.

489

Using an aspect of rapidity bins with finite sizes the short-range and long-range behaviors of two-particle correlation, the connection of two particle correlation function with factorial moment and factorial correlator are investigated; and experimental data for ¹⁶O+Em interactions at 14.6, 60 and 200 A GeV and ³²S+¹⁹⁷ Au interactions at 200A GeV are analyzed. It is shown that the bin-average of two-particle correlation function can naturally give a coordinate description of dynamical fluctuation such as the second order factorial moment〈F₂〉 and 1+1 order factorial correlator 〈F_1,1〉.

309

The absolute reaction rates in Be, Pb and Fe have been measured hy using the activation foil technique with different reaction energy thresholds. Thicknesses of Be, Pb and Fe spheres were 5.3, 19.1 and 31.9 cm, respectively. Eight kinds of activation foils were used for Fe, and four kinds each for Be and Pb. The total experimental error was about 5〜7%. The measured results were compared to the values calculated with the 1-D ANISN code and the ENDF/B-VI library data. The average ratio of the experimental to the calculational is less than 7% for Be and Pb, about 5-30% for Fe.

533

A corrective factor (Ψ(E,ρ) ≤1) dependent on ion energy and mass density of material for energy loss has been introduced into Bethe-Bloch formula, so that the energy deposition process of fast ion penetrating through the allotropic solid films are well discussed with the two-component assumption. An analysis expression of electronic stopping power for different phase structures has been derived from the contribution of "valence" and "core" electrons. The two thirds of inelastic scattering arisen from valence electron was revealed by comparing the theoretical calculation and experimental results on both random and oriented lattice site. The corrective factor representative to the role of inner electrons increases with the projectile energy but decreases with mass density of solids.

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The developed track detector consists of two parts: a small drift region to obtain a good tracking and a relatively large multiplication region for getting an enough high gain at low pressure. All the track detector can be moved in the direction perpendicular to the beam by means of a micrometric screw. An automatic system allows the counting gas to flow continuously at constant pressure through the detector during the measurements. The system can measure ionization distributions at a few nanometer range.

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The results of optical absorption analysis of the synthetic diamonds (type Ib) which were implanted with 40 keV molecular hydrogen ions at doses of 10¹⁵〜10¹⁷ H/cm² (at 100 K), showed that the increase of optical density (OD) of modified layer (〜140 nm) in UV-VIS region was dependent upon the damage level caused by ion implantation process. The range of relative optical band gap (E_{r, opt}) around 2.0 eV suggested that an amorphous carbon network structure like a-C film, which probably contains some localized subtetrahedral-coordinated clusters embedded in the fourfold (sp³) sites, was tentatively found in this layer, basing on the optical gap of carbon materials. The evolution of E_r,opt with ion fluence indicated that no more hydrogenated carbon compositions were produced in as-implanted samples, while the increase of E_r,opt with annealing temperature was very similar to that of hydrogen content dependence of E_opt in hydrogenately amorphous carbon (a-C:H). In addition the optical inhomogeneity of type Ib diamond has been revealed by a 2-dimension topograph in transmission mode at λ=430nm.

327

Correction factors of both Rem-meters, the 10 inch diameter single-sphere Remmeter and the standard A-B Rem-meter, were estimated for measuring high energy neutron dose equivalent outside a concrete shielding wall and the effects that the emitted neutron spectra become remarkably "harder" penetrated through a concrete shielding wall, and the energy response of the Rem-meter were taken in account. The estimated results could be applied in the measurement of neutron dose equivalent for the intermediate energy heavy ion reactions to avoid the difficulty induced by the energy response of the Rem-meters.

561

Sipping test device is used to identify the tightness of the irradiated fuel assembly during refuelling campaign. The gas is selected as the medium and the xenon-133 as the indicating nuclide. The device consists of the gas system, the γ-activity detection and measurement system, the power supply and signal system, the mechanical components and parts. The device has satisfactory functions, e.g. easy operation, indication in instrumentation, chart record and acoustic alarm, which can meet the operation demand of the nuclear reactor.

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The BMPPT (4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione) was synthesized from BMPP. Its m.p. is 106-108℃. The results of the element analysis are as follows: C, 68.51%, H, 4.51%, N, 9.26%, S, 11.47%, which are in conformity with the theoretical value (C, 69.15%, H, 4.76%, N, 9.52%, S, 10.90%). The solvent extraction of Th⁴⁺ from nitric acid solution by BMPPT in benzene was studied. The extraction ability of BMPPT is not so high as that of its parent (BMPP). The Th⁴⁺ distribution ratio (D_Th) increases with the increasing pH of the aqueous phase, and pH_1/2 for Th⁴⁺was 3.2 ([BMPPT]=0.10 mol/L). When the pH increases, the distribution ratio of Th⁴⁺ increases linearly with the slope of 1.59. When the concentration of BMPPT increases, the distribution ratio of Th⁴⁺ increases rapidly. The lgD_Th-lg[BMPPT] is linear with the slope of 1.42 and the extraction mechanism is the cation ion-exchange.

313

The protective ability of ascorbic acid (Vc) on stannous ion and the influence of light irradiation on the stability of stannous ion in diphosphonate medium at pH=5 have been examined in order to attain minimal loss of stannous ion during the production of lyophilized radiopharmaceutical kits. The sum of stannous ion and Vc was determined with iodometric method. It was shown that the protective ability of Vc was still strong at Vc concentration much lower than that of stannous ion and the illumination by fluorescent lamp was unfavorable to the stability of stannous ion. The change of pH in the range 3〜9 did not affect the action of Vc significantly.

267

Animals' regional femur blood (F) alteration was studied under an inadequate decompression by using the inhaled isotope ¹³³Xe washout method. Results showed that the average F on left and right side of minipigs' femur decreased from 15.4±1.8 and 16.9±2.0ml/ (100g•min) (before exposure) to 10±1.8 and 11.1±1.6ml/ (100mg•min) (after expposure for 1.5 h under the pressure of 0.5 MPa and then decompression to normal with the rate of 0.03〜0.04 MPa/min) , respectively; the blood flow of hematopoietic marrow tissues (f₁) on both sides also decreased from 19.3±2.0 and 22.1±1.9ml/ (100mg•min) to 13.9±1.4 and 13.8±1.0ml/(100mg·min) . The exact same alteration also happened in the experiment on New Zealand rabbits. It indicates that inadequate decompression in hyperbaric exposure can give rise to decrease animals' bone blood flow and insufficient bone blood supply serves as one of the reasons for causing decompressive osteonecrosis.

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