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A position-sensitive pixel array silicon detector with a junction field effect transistor (JFET) switch structure is studied as a device for the direct illumination of X-ray from synchrotron light source. Considering an absorption length of silicon at an X-ray energy and a required thickness of a silicon, a 525 μ m n-type silicon wafer with high resistivity is chosen as the active volume of the detector and is depleted by applying a negative bias voltage to the junction side. The electron–hole pairs produced in an active volume by an X-ray illumination are collected on the electrodes . All pixels with one row are read in parallel and the next row is selected by the control voltage after one row has finished being read. The field shaper is introduced to produce inter-pixel isolation. We perform the simulation of the pixelated silicon position detector with JFET switch and present the characteristics of the transistor such as the drain current as a function of the voltage between the source and drain for different gate voltages. The fabrication processes of the pixel sensor with JFET switch structure based on the simulation result are also described.

Chitosan-based composite films with different amounts of grapefruit seed extract (GFSE) (0.5, 1.0 and 1.5% v/v) were fabricated via solution casting technique. Experimental results showed that GFSE was uniformly dispersed within all chitosan film matrices. The presence of GFSE made the films more amorphous and tensile strength decreased, while elongation at break values increased as GFSE content increased. Results from the measurement of light transmission revealed that increasing amounts of GFSE (from 0.5 to 1.5% v/v) did not affect transparency of the films. Furthermore, packaging of bread samples with chitosan-based GFSE composite films inhibited the proliferation of fungal growth as compared to control samples. Hence, chitosan-based GFSE composite films have the potential to be a useful material in the area of food technology.

A prototype two-stage MSO (molten salt oxidation) reactor system with a capacity of 10 kg/h was developed based on the test results of lab-scale and bench-scale MSO systems. This study first discusses the features of the prototype MSO reactor system. The second part of the study attempts to identify the proper conditions of the prototype two-stage MSO reactor system, where each reactor performs different functions. The volatility of radioactive elements doped in the spent resins was first investigated to establish the proper operating conditions of the primary MSO reactor. A parametric model study of the secondary MSO reactor for the oxidation of hydrocarbons from the primary reactor and an experimental validation were then performed to establish the optimum conditions for the two-stage MSO reactor system. The retention of cesium was greatly influenced by the pyrolysis temperature. The highest pyrolysis temperature with cesium retention of ≥99.9% was 790 °C and this was established as the optimum primary reactor temperature. The optimum conditions of secondary MSO reactor for the substantial oxidation of hydrocarbons generated from the primary MSO reactor were determined to be λ (the ratio of actual air feed rate per stoichiometric air rate) of 2, and a temperature of 800 °C.

Effect of Cu and powder mixing with Cu-free (Nd, Dy)-Fe-B jet-milled powder on the magnetic properties of sintered magnets was investigated. The coercivity of a magnet prepared from the Cu-free (Nd, Dy)-Fe-B powder was about 10 kOe even though the alloy powder already contained some Dy (3.5 wt%). When small copper powder was blended, however, the coercivity of the magnet increased almost 100%, exhibiting about 20 kOe. On the contrary, the coercivity enhancement was moderate, about 4 kOe, when dysprosium content in the sintered magnet was simply increased to 4.9 wt% by the addition of small 3 powder.

Independent and cumulative production cross-sections for the (nat)Ti(p,x)(48)V, (43,44m,44g,46,47,48)Sc nuclear processes are reported here, for the energy region of 4-38MeV by using a stacked-foil activation technique. Measured data were critically compared with the earlier reported values, and also with the theoretical data from the TALYS and ALICE-IPPE codes. The measured (nat)Ti(p,x)(48)V reaction is important for charged particle beam monitoring purposes, whereas the (43,44,47)Sc radionuclide have various practical applications in nuclear medicine.

Transport and magnetization of MgIn 2− x Mn x O 4 polycrystalline pellets (0 x 2 O 4 with Mn results in an increase in electrical resistivity and a decrease in electron concentration. The electrical resistivity increases with decreasing temperature throughout the temperature range and variable-range hopping is observed at low temperatures. The diamagnetic pure MgIn 2 O 4 changes to paramagnetic after doping. The paramagnetism of the doped samples obeys the Curie–Weiss law. The magnetic-field dependence of the magnetization of the doped samples can be well described by the Brillouin function.

The second amendment to ‘German Rugulations on Consumer Goods’ states that azo dyestuffs, which can release one or more of the listed 20 carcinogenic amines, should no longer be used in dyeing consumer goods. Many acid and direct dyes which liberate harmful amines such as benzidine, o-tolidine and o-dianisidine after reduction are, however, still use. In this study, it was surprising to find that some dyestuffs or dyed substrates released carcinogenic amines such as 4-amino-diphenyl, 2-naphthylamine, 2,4-toluenediamine and 4,4′-diaminodiphenyl-methane, although such amines had not been employed as intermediates in the manufacture of the dyestuffs. Benzidine was also detected from a dyestuff which was not made from benzidine. The 2-naphthylamine residues were sourced as being due to the use of 1-naphthylamine contaminated with 2-naphthylamine. 4-Aminodiphenyl was formed by dediazoniation and a subsequent coupling reaction between the benzenediazonium ion and aniline. Benzidine was derived from dediazoniation and a subsequent self-coupling reaction of the diazonium ion of 4-nitroaniline. 2,4-Toluenediamine and 4,4′-diaminodiphenylmethane arose from the alkaline hydrolysis of the readily accessible moiety of the corresponding base units in PU foams or PU finishing agents.

We measured cross-sections for the formation of 86g,87m,87gY, 88,89gZr, and 90,92mNb radionuclides for proton-induced reactions on natural zirconium by using a conventional stacked-foil activation technique in the energy range between 1 and 40 MeV at the MC-50 cyclotron of the Korea Institute of Radiological and Medical Science. We compared the measured data with the available literature data and the theoretical calculation by the model codes TALYS and ALICE-IPPE. We also deduced the integral yields for thick targets from the measured cross-sections of the produced radionuclides. The optimum production possibility of the medically important 89gZr and 86Y radionuclides were discussed elaborately.

Two plateaux are observed in the desorption isotherm for palladium hydride: a lower plateau pressure for a hydrogen/metal atom ratio (H/M) less than about 0.3 and a slightly higher plateau pressure for H/M greater than about 0.3. This higher pressure corresponds to the reported pressure for palladium hydride. These observations were made for a large surface area palladium powder exposed to both protium and tritium. Helium buildup from tritium decay decreases the lower plateau pressure but does not affect the observations for H/M greater than about 0.3. A multiple-energy hydrogen site occupancy model is proposed to explain qualitatively both the dual plateau and the helium effect in palladium hydride.

The Alpha Magnetic Spectrometer (AMS) was flown on the space shuttle Discovery during flight STS-91 (June 1998) in a 51.7 deg orbit at altitudes between 320 and 390 km. A search for antihelium nuclei in the rigidity range 1–140 GV was performed. No antihelium nuclei were detected at any rigidity. An upper limit on the flux ratio of antihelium to helium of < 1.1×10^−6 was obtained. The high energy proton, electron, positron, helium, antiproton and deuterium spectra were accurately measured. For each particle and nuclei two distinct spectra were observed: a higher energy spectrum and a substantial second spectrum. Positrons in the second spectrum were found to be much more abundant than electrons. Tracing particles from the second spectra shows that most of them travel for an extended period of time in the geomagnetic field, and that the positive particles (p and e+) and negative ones (e−) originate from two complementary geographic regions. The second helium spectrum flux over the energy range 0.1–1.2 GeV/nucleon was measured to be (6.3 ± 0.9) × 10^−3(m^2 s sr)^−1. Over 90 percent of the helium flux was determined to be 3He at the 90% confidence level

Hydrogen (H) absorption by YBa 2 Cu 3 O 7− δ (YBCO) was carried out by exposing the superconducting powders to rf-generated H plasma. We find that both the field-cooled (FC) and zero-field-cooled (ZFC) susceptibilities increase after hydrogenation. The largest enhancement is about 24% for the FC susceptibility at 5K.