Humidity Sensor Characteristics of Woodceramics

The humidity sensor characteristics of Woodceramics were investigated. The Woodceramics used in this experiment were prepared at 650–900°C. The size of specimens selected was 1 × 1 × 10 mm . One was used as-cut and the other was polished. Above 700°C, the resistance of the specimen was below 50 and the decrease of resistance with increasing relative humidity was small. The specimen prepared at 650°C had a resistance of about 1 k. The resistance of as-cut specimens decreased with increase in relative humidity, but that of the polished specimen did not change significantly. The difference between as-cut and polished samples was explained by the differences in surface micro-structure.     

High oleic acid oil suppresses lung tumorigenesis in mice through the modulation of extracellular signal-regulated kinase cascade

This study was undertaken to estimate the effect of dietary high oleic acid oil (OA) on 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced lung tumorigenesis in mice. Diet containing 10% oil was fed to mice through experimental periods. On day 30 after NNK injection (100 mg/kg body weight, i.p.), the treatment increased the level of prostaglandin E₂ (PGE₂) as well as proliferating cell nuclear antigen, a marker of cell proliferation in a high linoleic acid oil (LA)-fed group but not in an OA-fed group. The NNK treatment also induced the activation of an extracellular signal-regulated kinase (Erk) cascade (Erk, Mek and Raf-1) in an LA-fed group. On the other hand, OA feeding abolished the NNK-induced activation of the Erk cascade. In conjugation with these events, OA feeding reduced lung tumor incidence and tumor multiplicity (percentage of mice with tumors) in mice compared with LA feeding at the 20th experimental week. These results suggest that OA suppresses lung tumorigenesis and that this suppression is correlated with the inhibition of PGE₂ production and inactivation of the Erk cascade.     

Fractal analysis of the surface cracks on continuously cast steel slabs

Data concerning the length of longitudinal cracks on the surface of continuously cast steel slabs were collected from two plants. The data were analyzed to find the relation between crack length and crack frequency. The analysis revealed the following.

Combustion Characteristics of High Burn Rate Azide Polymer Propellant

The combustion characteristics of high burn rate azide polymer composite propellant were examined by using a chimney type strand burner, a Ø 80 mm × 140 mm small rocket motor and a L/D = 16 of Ø 70 mm heavy-wall rocket motor. The propellant, BAMO/NMMO copolymer was used as a fuel binder and AP as an oxidizer, burned approximately 29 mm/s at a pressure range of 7 MPa to 20 MPa with a plateau-mesa burning behavior. However, the pressure exponent rapidly increased at above the pressure of 20 MPa and was 0.52 between 20 MPa and 25 MPa. The low pressure exponent and high burn rate of the azide polymer propellant are suitable to the short burn time at the maximum expected operating pressure range of 15 MPa to 20 MPa. The high L/D heavywall rocket motor with volumeric mass fraction of 83% showed stable combustion without any pressure oscillation and severe erosive burning. The average burn rate in the high L/D motor was 10% larger than that estimated from the strand data. The theoretically calculated pressure-vs-time and thrust-vs-time curves were well consistent with the measured data. α = 20 and β = 180 for the Lenoir-Robillard equation were used to estimate the burn rate.     

Detection of aluminium by energy dispersive X-ray microanalysis at high accelerating voltages with semi-thin sections of biological sample

Aluminium (Al) was detected in semi-thin sections of three organs, the duodenum, liver and kidney, of ddY strain mouse by energy dispersive X-ray microanalysis at high accelerating voltages around 300 kV. Firstly, to determine the conditions best for detecting Al, several adult ddY mice were injected intraperitoneally with aluminium chloride (AlCl3) and the duodenums were fixed, embedded and sectioned at various thicknesses and subjected to energy dispersive X-ray microanalysis at various accelerating voltages from 100 to 400 kV. From the results obtained, 1.0 microm-thick sections observed at 300 kV resulted in the highest peak-counts/background ratios and were shown to be the most suitable for X-ray microanalysis. Secondly, ddY mice aged four weeks were administered orally with 2% AlCl3 at pH 2.5 for two weeks and the three organs (duodenum, liver and kidney) were subjected to X-ray microanalysis under the same condition found above. The results were compared with light microscopic Al staining of the same tissues. Aluminium was detected in lysosomes of the three kinds of tissues with higher sensitivity by energy dispersive X-ray microanalysis by light microscopic observation. From the results, it was suggested that Al dissolved in acidic water was absorbed in the duodenum and accumulated in the liver and kidney.     

Automatic electron beam alignment adjustment system and automatic filament current adjustment system for electron beam welder

Recently, the electron beam welders with high acceleration voltage (more than 100 kV) and high electrical power (more than 15 kW) have been reviewed the role of the high-energy electron beam density again, due to space or aircraft development or automobile industry desired high productivity and high accurate welding for saving energy. NEC group have supplied these electron beam welders. This time, the automatic alignment adjustment system of the electron beam orbit and the automatic adjustment system of filament current were developed and put to a practical use. As a result, the great effectiveness for the stability of welding quality was apparent.     

High intergrain critical current density in fine-grain (Ba0.6K0.4)Fe2As2 wires and bulks

The K- and Co-doped BaFe(2)As(2) (Ba-122) superconducting compounds are potentially useful for applications because they have upper critical fields (H(c2)) of well over 50?T, H(c2) anisotropy γ < 2and thin-film critical current densities J(c) exceeding 1?MA?cm(-2) (refs 1-4) at 4.2?K. However, thin-film bicrystals of Co-doped Ba-122 clearly exhibit weak link behaviour for [001] tilt misorientations of more than about 5°, suggesting that textured substrates would be needed for applications, as in the cuprates. Here we present a contrary and very much more positive result in which untextured polycrystalline (Ba(0.6)K(0.4))Fe(2)As(2) bulks and round wires with high grain boundary density have transport critical current densities well over 0.1?MA?cm(-2) (self-field, 4.2?K), more than 10 times higher than that of any other round untextured ferropnictide wire and 4-5 times higher than the best textured flat wire. The enhanced grain connectivity is ascribed to their much improved phase purity and to the enhanced vortex stiffness of this low-anisotropy compound (γ~1-2) when compared with YBa(2)Cu(3)O(7-x) (γ~5).