Development of GIS fault location system using pressure wavesensors

This paper describes a series of development tests carried out when developing a GIS (gas insulated substation) fault location system using pressure wave sensors for a GIS with a main bus in which each gas section per bay is connected by gas piping. This paper also refers to the basic construction of the software of the fault location system actually applied to a GIS with a rated voltage of less than 168 kV     

In Situ measurement of effective gas diffusivity through hematite pellets during stepwise reductions

The Wicke-Kallenbach (W-K) method for effective gas diffusivity measurements could only be used in the vicinity of ambient temperatures. However, in the present study, this technique has been extended to temperatures of about 1273 K through use of a high-temperature cement. This newly developed high-temperature W-K method was applied toin situ measurements of the diffusive and viscous fluxes through hematite pellets during stepwise reductions. When the sam-ple (acid and basic pellets) is reduced, it swells significantly. However, a gas-tight seal between the holder and specimen was successfully maintained by use of a high-temperature cement. This cement, composed mainly of Na₂O (20 mass pct) and SiO₂, separates into a solid and liquid phase at elevated temperatures. Thus, it can move in the same direction as the expansion of sample and thereby maintain the gas-tight seal. With this new technique, the structural param-eters of gases based on the “dusty gas model” for D’Arcy’s flow, Knudsen diffusion, and mo-lecular diffusion were obtained. These parameters were compared with those estimated through pore structure models.     

Evaluation of tricuspid regurgitation by the ultrasonic pulsed Doppler technique from a transcutaneous approach (author's transl)

Severity of tricuspid regurgitation was assessed by using a combined system of the ultrasonic pulsed Doppler technique and two-dimensional echocardiography from a transcutaneous approach. The study group comprised 47 patients with various heart diseases, who were clinically presumed to have tricuspid regurgitation, and 10 healthy subjects. 1) Pansystolic abnormal flow signal was detected in an area from the tricuspid valve into the right atrial cavity in 43 patients including 8 patients without definitive signs of tricuspid regurgitation. Such abnormal flow had never been detected in healthy subjects and was considered to represent tricuspid regurgitant flow. Tricuspid regurgitant flow usually exhibited a wide band spectrum of velocity component indicating a disturbed flow. In 4 patients with clinical signs of severe tricuspid regurgitation, a laminar flow was detected in the right atrial cavity, which was considered to indicate a regurgitant jet in the central part of tricuspid regurgitant flow. 2) The area where tricuspid regurgitant flow was detected was interpreted as revealing the main direction and spread of tricuspid regurgitant flow. Based on this finding, severity of TR was classified into 4 grades by the assessment on the basis of the distance reached by tricuspid regurgitant flow in the right atrium. Severity of tricuspid regurgitation was also classified into 4 grades by right ventriculography. The grade of tricuspid regurgitation assessed by Doppler technique was nearly consistent with that assessed by right ventriculography. Severity of tricuspid regurgitation was also classified into 4 grades on the basis of the extent of the area where the regurgitant flow spread, and nearly the same results were obtained as those described above. 3) Thus, the combined use of Doppler flowmetry and two-dimensional echocardiography proved to be useful for detecting tricuspid regurgitant flow and assessing the severity of tricuspid regurgitation.     

Conformational analysis of serricornin: Application of molecular mechanics calculations to stereochemical assignment of serricornin,sex pheromone of cigarette beetle (Lasioderma serricorne F.)

Conformational analysis using molecular mechanics (MM) was performed for a determination of the stereochemistry of serricornin, the sex pheromone of the cigarette beetle (Lasioderma serricorne F.). An exhaustive conformational analysis using MM2 calculations with algorithms for covering torsional energy surfaces of flexible molecules furnishes coordinates and steric energies of all local energy minimum conformers of serricornin, both acyclic and the corresponding cyclic forms. These coordinates gave angles required for the calculation of vicinal H/H coupling constants (³ J _HHs) of each energy minima by Altona's modified Karplus equation. The Boltzmann distributions of all local energy minima were calculated from their steric energies to furnish populations of each energy minimum conformer. Populationweighted averaged³ J _HHs of four enantiomeric pairs, (S ^*,S ^*,S ^*)-, (S ^*,S ^*,R ^*)-, (S ^*,R ^*,S ^*)-, and (R ^*,S ^*,S ^*)-serricornins were calculated from the data above. The observed³ J _HHs of the naturally occurring serricornin, both acyclic and cyclic forms, are fitted best to calcd.³ J _HHs of (4S ^*, 6S ^*, 7S ^*)-acyclic and (3S ^*, 5S ^*, 6S ^*)-cyclic serricornin, respectively, among those of four enantiomeric pairs of serricornin.     

Parameter of local cyclic strain distribution

The local cyclic strain distribution near the crack tip was investigated by the Computer Aided Fine Grid Method. This method makes it possible to measure continuously every in-plane component of local cyclic strain distribution. It was found that the magnitude of the local cyclic strain distribution near the crack tip was varied by the applied cyclic load level and the material, but the shape of the local cyclic strain distribution near the crack tip was experimentally scarcely altered.

The local cyclic strain field near the crack tip could be written as the following equation. Δε_eq(r, θ) = ΔA · f(θ) · r⁻¹ A single parameter ΔA, which characterizes the local cyclic strain field near the crack tip, was newly proposed by authors.     

Immunohistochemical demonstration of carcinogen-DNA adducts in tissues of rats given 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP): detection in paraffin-embedded sections and tissue distribution

A polyclonal antibody against 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-DNA adducts was raised for their immunohistochemical demonstration in paraffin-embedded sections. Specificity of this antibody was confirmed by competitive ELISA. Positive signals were immunohistochemically detected in acetone-fixed but not in formalin- or ethanol-fixed sections from F344 rats treated by gavage with a single dose of PhIP at 37.5-300 mg/kg and killed at 1, 2, and 7 days thereafter. Dose-dependent positive staining was observed in almost all organs of both sexes, including the colon, prostate, and mammary gland but largely independent of the tumor response. Repair activity, judged by disappearance of adducts with time, differed according to the organ or cell type. One exception was hepatocytes, the liver incidentally being a nontarget organ. The results suggest that the generated antibody is applicable for detection of cells targeted by PhIP in paraffin-embedded sections and also for the investigation of the mechanisms of PhIP-carcinogenesis.     

A bio-electrochemical reactor coupled with adsorber for the removal of nitrate and inhibitory pesticide

In this study, the treatment characteristics of nitrate and toxic pesticide by a combined bioelectrochemical reactor (BER)/adsorption process was investigated. Experimental results showed that the disappearance of NO3- in BER was in accordance with the applied current. NO2- was not detected in the effluent, but the production of N2O was increased with increasing IPT loading. In the presence of IPT, up to 30% of the nitrate nitrogen consumed was converted to N2O, while more than 95% converted to N2 in the absence of IPT. In adsorption column, IPT was efficiently removed onto either granular activated carbon or silicone resin so as to meet the guideline value (40 microg/I) and to reduce the N2O accumulation. A simplified kinetic model that considers the sequential reduction of nitrate and inhibition of the N2O reduction step by pesticide as well as Langmuir adsorption isotherm was developed and used to evaluate the process performance. Theoretically predicted effluent concentrations were in good agreement with the observed results for nitrate, nitrite, N2O, N2 and IPT. It was considered that high removal performance of nitrate and pesticide by the combined process is attributable to high affinity of adsorbates for IPT in comparison with relatively large inhibition constant (Ki).     

Aryl Polyenes,a Highly Abundant Class of Bacterial Natural Products,Are Functionally Related to Antioxidative Carotenoids

Bacterial pigments of the aryl polyene type are structurally similar to the well‐known carotenoids with respect to their polyene systems. Their biosynthetic gene cluster is widespread in taxonomically distant bacteria, and four classes of such pigments have been found. Here we report the structure elucidation of the aryl polyene/dialkylresorcinol hybrid pigments of Variovorax paradoxus B4 by HPLC‐UV‐MS, MALDI‐MS and NMR. Furthermore, we show for the first time that this pigment class protects the bacterium from reactive oxygen species, similarly to what is known for carotenoids. An analysis of the distribution of biosynthetic genes for aryl polyenes and carotenoids in bacterial genomes is presented; it shows a complementary distribution of these protective pigments in bacteria.