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Notes: Fe-Cr-Co ductile alloys produce magnetic properties comparable to those of Alnico permanent magnets family, up to (BH)max=91.2 kJ/m3(11.4 MGOe). It is technologically known that the addition of Ti to the Fe-Cr-Co alloys extends the α-phase region of system and improves the magnetic properties. The purpose of this work is to study the effect of Ti on microstructures and magnetic properties of Fe-Cr-Co alloys. The microstructures of Fe-25 wt.% Cr-12 wt.% Co alloys with or without Ti melted in air or in vacuum, were studied by optical microscopy, electron probe microanalysis (EPMA), and transmission electron microscopy (TEM). The alloys without Ti exhibit the precipitates of Cr23C6 carbide and Cr2N nitride a along the grain boundary or inside grain. These carbides and nitrides form the Cr-depleted zone around them. However, the addition of Ti suppressed the formation of Cr-depleted zone, in forming the Ti(C,N), and the magnetic properties are improved.

Notes: The effective permeability ( μeff) of the ring Sendust alloys (Fe-9–10 wt. % Si-5–7 wt. %Al), molded with Epoxy resin, was measured in the temperature range of −10 to 70 °C. The μeff of the alloys in molded condition measured at 20 °C is smaller than that in unmolded condition. The high values of the μeff at 20 °C of the molded alloys were obtained from the alloys in which magnetostriction constants (λs) were close to zero. The temperature dependencies of the μeff for the studied alloys in the unmolded condition are very similar, but after molding they are classified into four variations depending on the value of λs. When the alloys have large positive or negative values of λs, the μeff increases or decreases monotonically with increasing temperatures, but for the alloy with λs (approximately-equal-to)0, the μeff temperature dependence is complex. These behaviors of the μeff with temperature are interpreted on the basis of the induced stress, initiating from the differences in thermal expansion between alloys and Epoxy resin. The μeff of the molded alloys was mainly dominated by the induced uniaxial magnetic anisotropy (Ku) by the tangential and axial compressive stresses in the molded ring alloys.

Notes: Infrared absorption, electron paramagnetic resonance (EPR) spectra, and the electrical resistivity of semi-insulating liquid encapsulated Czochralski GaP crystals irradiated by fast neutrons with a dose of 7.6×1018 n cm−2 have been studied. The electrical resistivity decreases with irradiation from 106 Ω cm to 1.5 kΩ cm. The temperature dependence of resistivity at low temperature is fitted to exp(b/T1/4). The strong continuous optical absorption extends to 0.32 eV and its tail spreads until 0.12 eV. The EPR spectrum exhibits a broad singlet at 77 K and a doublet with five line structures at room temperature, which is attributed to antisite defects PGa. The strong infrared absorption begins to be annealed at 150 °C, and the EPR broad singlet decreases with anneals in the same temperature range. The strong infrared absorption is assumed to arise from interstitial phosphorus clusters. A discussion is given concerning the species responsible for the EPR singlet.

Notes: The authors report the functional analysis of the purified mouse factor H allotypes H. 1 and H.2, which were clearly distinguished from each other by an immunodiffusion test. Both allotypes acted as a co-factor for factor I in cleaving mouse C3b and we found no significant difference between their activities. The results strongly suggest that the function of mouse factor H for the co-factor activity has been well conserved between two allotypes.

Notes: This paper deals with the effect of anisotropy on fracture processes of a directionally solidified superalloy, Mar-M247, under a push–pull creep-fatigue condition at high-temperature. Three kinds of specimen were cut from a cast plate such that their axes possess angles of 0°, 45° and 90° with respect to the 〈001〉 orientation that is aligned parallel to the solidification direction (also to the grain boundaries and primary dendrite axis); these specimens being denoted the 0° specimen, the 45° specimen, and the 90° specimen, respectively. The tests were conducted at 1273 K (1000 °C) in air under equal magnitudes of the range of a ΔJ-related parameter, ΔWc , which represents the driving force for crack growth in creep-fatigue. Although the grain boundaries are macroscopically parallel to the solidification direction, they are wavy or serrated microscopically. Small cracks nucleate along parts of the grain boundaries perpendicular to the stress axis in all specimens. The 90° specimen has the shortest crack initiation life and the 0° specimen has the longest. In the 90° and 45° specimens, intergranular cracks continue to nucleate and a main crack is formed along the grain boundary due to the frequent coalescence of small cracks. In the 0° specimen, cracks grow into the grain, and transgranular cracks coalesce along the primary dendrite or grain boundary. The 0° specimen exhibits the slowest crack growth rate and the 90° specimen the fastest. These differences in the initiation and growth behaviour of small cracks cause the longest failure life in the 0° specimen and the shortest in the 90° specimen.

Notes: This paper deals with the initiation and growth of small cracks in a directionally solidified superalloy, Mar-M247.

Notes: : There have been no reports concerning the efficacy and safety of a 1-week quadruple therapy regimen of omeprazole, amoxycillin, roxithromycin and metronidazole for Helicobacter pylori infections and the impact of primary resistance on the eradication rate.〈section xml:id="abs1-2"〉〈title type="main"〉Methods: One hundred and sixty-nine consecutive patients with peptic ulcer disease as well as gastritis with biopsy-proven H. pylori infection were entered into an open study of omeprazole 20 mg o.m., amoxycillin 500 mg t.d.s., roxithromycin 150 mg b.d., and metronidazole 250 mg t.d.s. Helicobacter pylori status was determined by urease test, histology and culture. Susceptibility to amoxycillin, metronidazole and roxithromycin was determined by the E-test.〈section xml:id="abs1-3"〉〈title type="main"〉Results: H. pylori was eradicated in 155 out of 169 (92%; 95% CI 88–96%) by intention-to-treat analysis, and in 155 out of 163 (95%; 95% CI 92–98%) by per protocol analysis. The prevalence of primary resistance against amoxycillin, roxithromycin and metronidazole was 2 out of 166 (1%), 16 out of 166 (10%) and 27 out of 166 (16%), respectively. H. pylori was eradicated in 25 out of 27 (93%) patients with metronidazole-resistant strains compared with 130 out of 136 (96%) in patients with metronidazole-sensitive strains of H. pylori. It was eradicated in 15 out of 16 (94%) patients with roxithromycin-resistant strains while in 140 out of 147 (95%) patients with roxithromycin-sensitive strains of H. pylori, and in two out of two (100%) patients with amoxycillin-resistant stains compared with 153 out of 161 (95%) in patients with amoxycillin-sensitive strains. H. pylori was eradicated in three out of four (75%) patients with double resistance against metronidazole and roxithromycin compared with 152 out of 159 (96%) patients with sensitive strains to metronidazole and or roxithromycin. None of these differences were statistically significant. Severe side-effects were found in only one out of 169 patients—anaphylaxis due to penicillin.〈section xml:id="abs1-4"〉〈title type="main"〉Conclusions: The 1-week quadruple therapy with omeprazole, amoxycillin, metronidazole and roxithromycin was found to eradicate H. pylori in over 90% of all patients. This regimen was also found to be beneficial for patients with pre-treatment resistant strains to metronidazole, roxithromycin or amoxycillin, and was observed to be safe and well-tolerated.