Corrosion characteristics of reduced activation ferritic steel, JLF-1 (8.92Cr–2W) in molten salts Flibe and Flinak

Static corrosion tests were performed in molten salts, LiF–BeF₂ (Flibe) and LiF–NaF–KF (Flinak), at 500 °C and 600 °C for 1000 h. The purpose is to investigate the corrosion characteristics of reduced activation ferritic steels, JLF-1 (8.92Cr–2W) in the fluids. The concentration of hydrogen fluoride (HF) in the fluids was measured by slurry pH titration method before and after the exposure. The HF concentration determined the fluoridation potential. The corrosion was mainly caused by dissolution of Fe and Cr into the fluids due to fluoridation and/or electrochemical corrosion. Carbon on the surface might be dissolved into the fluids due to the corrosion, and this resulted to the decrease of carbide on the surface. The corrosion depth of the JLF-1 specimen, which was obtained from the weight losses, was 0.637 μm in Flibe at 600 °C and 6.73 μm in Flinak at 600 °C.     

LiErO2 formation on Er2O3 in static and natural convection lithium

Er₂O₃ is candidate material for insulating coating to prevent the magnetohydrodynamic (MHD) pressure drop in the self-cooled liquid Li blanket system. Although Er₂O₃ is stable material, detailed chemical behavior in liquid Li is not clear. Corrosion behavior of bulk Er₂O₃ in Li is investigated in static and flowing condition in the present study. After these tests, good compatibility of Er₂O₃ was confirmed and slight formation of LiErO₂ was detected by XRD analysis. This chemical behavior did not change in a static and flowing tests, however some of the corrosion product of LiErO₂ was removed easily by the Li flow. Intensity of LiErO₂ peaks in XRD spectrum suggests that the temperature gradient may affect the reaction rate in the natural convection loop. Since corrosion rate of Er₂O₃ is very small, slight change in state will be important information to evaluate lifetime of coating.     

Susceptibilities of bacteria isolated from patients with lower respiratory infectious diseases to antibiotics (1996)

The bacteria isolated from the patients with lower respiratory tract infections were collected by institutions located throughout Japan, since 1981. Ikemoto et al. have been investigating susceptibilities of these isolates to various antibacterial agents and antibiotics, and characteristics of the patients and isolates from them each year. Results obtained from these investigations are discussed. In 16 institutions around the entire Japan, 557 strains of presumably etiological bacteria were isolated mainly from the sputa of 449 patients with lower respiratory tract infections during the period from October 1996 to September 1997. MICs of various antibacterial agents and antibiotics were determined against 98 strains of Staphylococcus aureus, 93 strains of Streptococcus pneumoniae, 84 strains of Haemophilus influenzae, 84 strains of Pseudomonas aeruginosa (non-mucoid strains), 17 strains of Pseudomonas aeruginosa (mucoid strains), 31 strains of Moraxella subgenus Branhamella catarrhalis, 21 strains of Klebsiella pneumoniae etc., and the drug susceptibilities of these strains were assessed except for those strains that died during transportation. 1) S. aureus S. aureus strains for which MICs of oxacillin (MPIPC) were higher than 4 micrograms/ml (methicillin-resistant S. aureus) accounted for 67.3%. The frequency of the drug resistant bacteria increased comparing to the previous year's 52.7%. Arbekacin (ABK) and vancomycin (VCM) showed the highest activities against both S. aureus and MRSA with MIC80s of 1 microgram/ml. 2) S. pneumoniae Imipenem (IPM) and panipenem (PAPM) of carbapenems showed the most potent activities with MIC80s of 0.063 microgram/ml. Faropenem (FRPM) showed the next potent activity with MIC80 of 0.125 microgram/ml. The other drugs except erythromycin (EM), clindamycin (CLDM) and tetracycline (TC) were active against S. pneumoniae tested with MIC80s of 8 micrograms/ml or below. 3) H. influenzae The activities of all drugs were potent against H. influenzae tested with MIC80s of 4 micrograms/ml or below. Cefotiam (CTM), cefmenoxime (CMX), cefditoren (CDTR) and ofloxacin (OFLX) showed the most potent activities with MIC80s of 0.063 microgram/ml. 4) P. aeruginosa (mucoid strains) Tobramycin (TOB) showed the most potent activity against P. aeruginosa (mucoid strains) with MIC80 of 1 microgram/ml. Ceftazidime (CAZ), cefsulodin (CFS), IPM, gentamicin (GM), ABK and ciprofloxacin (CPFX) showed the next potent activities, with MIC80s of 2 micrograms/ml. The MIC80s of the other drugs ranged from 4 micrograms/ml to 16 micrograms/ml. 5) P. aeruginosa (non-mucoid strains) TOB and CPFX showed the most potent activities against P. aeruginosa (non-mucoid strains) with MIC80s of 1 microgram/ml. The MIC80s of piperacillin (PIPC) and cefoperazone (CPZ) were 16 micrograms/ml in 1995, and they were 64 micrograms/ml in 1996. 6) K. pneumoniae All drugs except ampicillin (ABPC) were active against K. pneumoniae. CMX, cefpirome (CPR), cefozopran (CZOP) and carumonam (CRMN) showed the most potent activities against K. pneumoniae with MIC80s of 0.125 microgram/ml. The MIC80s of the other drugs ranged from 0.25 microgram/ml to 2 micrograms/ml. 7) M.(B) catarrhalis Against M.(B.) catarrhalis, all drugs showed good activities with MICs of 4 micrograms/ml or below. IPM and minocycline (MINO) showed the most potent activities with MICs of 0.063 microgram/ml. Also, we investigated year to year changes in the characteristics of patients, their respiratory infectious diseases, and the etiology. Patients' backgrounds were examined for 557 isolates from 449 cases. The examination of age distribution indicated that the proportion of patients with ages over 60 years was 71.0% of all the patients showing a slight increase over that in 1994. Proportions of diagnosed diseases were as follows: Bacterial pneumonia and chronic bronchitis were the most frequent with 35.9% and 30.3% respectively. They were followed by bronchiectasis with a proportion of 10.     

Growth of β-FeSi2 thin films on β-FeSi2 (110) substrates by molecular beam epitaxy

We have investigated the preparation of β-FeSi₂ substrate and growth condition of β-FeSi₂ thin film on β-FeSi₂ (110) substrate by molecular beam epitaxy. The surface of the substrate was prepared by a wet-etching using HF(50%):HNO₃(60%):H₂O = 1:1:5 solution at 25 °C. It is clear that the optimal etching period to obtain a flat surface was 3 min. The β-FeSi₂ thin film with streak RHEED pattern was obtained at Si/Fe flux ratio of 2.9. Average surface roughness (Ra) of the β-FeSi₂ film was about 0.5 nm in 5 × 5 μm² area.     

Microstructure Control of Sintered Porous Yttria-Stabilized Zirconia as a Durable Thermal Shielding Material

The microstructure of a thermal shielding material affects its thermal conductivity and mechanical property. In this study, the effects of the sintering temperature and the polymethyl methacrylate powder as a pore-former on the microstructure of a sintered porous yttria-stabilized zirconia (YSZ), which is used as a durable thermal shielding material, were investigated. It became clear that the microstructure of the sintered YSZ could be controlled by the particle size and the amount of the pore-former and the sintering temperature. The effect of the yttria amount in the YSZ on the microstructure was also clarified.     

One-Step Oxidation of Benzene to Phenol over Cu/Ti/HZSM-5 Catalysts

The gas-phase catalytic oxidation of benzene over copper supported on HZSM-5 added with titanium (Cu/Ti/HZSM-5) was carried out by using molecular oxygen as an oxidant. Phenol was effectively produced by the titanium addition to Cu/HZSM-5. The titanium addition to Cu/HZSM-5 induces the easy reduction of Cu²⁺ species to Cu⁺ species in the catalysts, and the produced Cu⁺ species seems to produce the phenol effectively.     

Highly reliable oxide‐semiconductor TFT for AMOLED displays

Abstract— The stability and reliability of oxide‐semiconductor TFTs were investigated. The contact material to the oxide semiconductor affected the thermal stability of the TFT, and a molybdenum‐contact source/drain showed good stability. And the passivating film and TFT structure affected the stability against bias stress and humidity stress, and dc‐sputtered Al²O³ passivation and fully covered channel structure with an etching stopper or source/drain showed good reliability. Moreover, high photo‐stability was confirmed by the bias‐enhanced photo‐irradiation stress test. An 11.7‐in.‐diagonal qHD AMOLED display was demonstrated to provide an applicable solution for a large‐sized OLED and an ultra‐high‐definition LCD‐TV mass production.