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The excitation testing of high temperature superconducting (HTS) coil with Bi2212 cables is examined for development of high energy density superconducting magnetic energy storage (SMES). Findings reveal the confirmation of sufficient thermal stability during the thermal runaway test.

A design of a cryocooler-cooled 19 T superconducting magnet that contains a Bi2223 insert coil composed of 25 double pancake coils, Nb(sub 3)Sn coils using a Nb(sub 3)Sn wire reinforced with nb-Ti-Cu compound is presented. A preliminary experiment is carried out in order to examine the influence of the bending strain upon a maximum permissible hoop stress of Ag-sheathed Bi223 tape conductor.

Research is presented describing the Nb3Sn and NbTi cable-in-conduit conductors used in the International Thermonuclear Experimental Reactor project, and cooled by a supercritical helium forced flow. The design of the conductors, and non-uniform distribution between superconducting strands, are discussed.

The International Thermonuclear Experimental Reactor central solenoid model coil conductors were studied to determine predicted thermohydraulic performance.

Test results of the 460-kA Nb3Sn conductor joint for the ITER model coils are presented.

Development efforts for a quick response type 70 MW class superconducting generator are presented. A double stranded cable of NbTi, CuNi and Cu was employed as the superconductor configuration for the generator's field winding. Intra-strand alternating current losses were reduced by introducing a strand with additional Cu-0.5wt%Mn fins in the Cu sheath. Tests reveal that additional fins in the Cu sheath led to significant decreases in coupling and eddy current losses.

A double-stranded cable for use in the field winding of a 70-MW superconducting generator was characterized. Specifically, measurements of inter-strand resistance and ac losses were carried out on a formvar-insulated cable made of niobium-titanium, copper and copper-nickel wires. The results, which enabled correlations between inter-strand resistance and inter-strand coupling loss, revealed a larger strand deformation at the Z-S contact plane than in the Z-Z level.

OBJECTIVE: To investigate the effects of vibration (Vib) and hyaluronic acid (HA) on 3-dimensional cultured cartilage. METHODS: Chondrocytes were obtained from metatarsophalangeal joints of freshly killed 6-month-old pigs. Twenty-four-well plates containing type I collagen sponge disks were used to culture samples. The frequency and the amplitude of the vibration of the well plate were 100 Hz and 0.5 nm, respectively. We produced 3-dimensional cartilage tissue using HA and vibration with collagen sponge as a carrier. Four different culture conditions were examined: a control HA-Vib- group, an HA-Vib+ group, an HA+Vib- group, and an HA+Vib+ group. Each group was cultured for 2 weeks. After culture days 3, 7, 10, and 14 (every 3.5 days), the levels of chondroitin 4-sulfate (C4S) and chondroitin 6-sulfate (C6S) isomers synthesized in each culture medium were measured. Histologic analysis, immunohistochemical analysis, and electron microscopic examination were performed. RESULTS: Mean C4S and C6S synthesis had increased rapidly after 7 days of culture and continued to increase thereafter. There were significant differences among the 4 groups (P < 0.01). Synthesis of both C4S and C6S was most abundant in the HA+Vib+ group and the lowest in the HA-Vib- group. After 1 and 2 weeks of culture, the chondrocytes had formed stratified structures on the collagen sponges in all groups, although the thickest structure was observed in the HA+Vib+ group and the thinnest in the HA-Vib- group. Under immunofluorescence, the HA+Vib+ group exhibited the strongest chromatic features. Under electron microscopy, the chondrocytes in the HA+Vib+ group exhibited many long and slender prominences on their surface, and extracellular substance could be observed associated with the cells. CONCLUSION: Our results indicate that the combination of vibration and HA activates the production of proteoglycan in 3-dimensional cultured chondrocytes and stimulates MAPK and beta-catenin. This suggests that some mechanoreceptors for vibration exist on the plasma membrane of chondrocytes and activate the intracellular signal transduction system. [ABSTRACT FROM AUTHOR]

Capacitor oil samples (PCBs > 90%wt) were treated in a bench scale experiment to investigate the destruction of PCBs during chemical destruction processes (a catalytic hydrodechlorination treatment with palladium carbon and additional treatment with potassium tert-butyloxide). Using those results, this study confirmed the decrease of PCBs and other undesirable dioxin-like compounds such as PCDD/Fs in treated samples during the treatment. Dioxin-responsive chemical-activated luciferase expression (DR CALUX®) AhR reporter gene bioassay was used to evaluate dioxin-like activity in the samples. During the treatment, the efficiency for PCB capacitor oil was around 99.99% or more in WHO-TEQ and CALUX-TEQ, whereas the sum of PCBs was reduced at a resulting efficiency of >99.9999%. In this study, a new cleanup procedure for separating PCBs from the mineral oil matrix was also developed for DR CALUX. The procedure consists of dimethylsulphoxide partitioning followed by silica gel-44% sulphuric acid reflux treatment and activated carbon chromatography. With the cleanup, CALUX-TEQ values were in good agreement with WHO-TEO, values and were as much as 3.3 times higher than WHO-TEQs for untreated/treated PCB-containing insulating oil samples. The DR CALUX results of mineral oil samples containing various PCB concentrations of 0.5–50 mg/kg (corresponding WHO-TEQs: 0.012–1.2 μg-TEO]g) also correlated well with WHO-TEQs (CALUX-TEQ/WHO-TEQ ratio = 1.0–3.0), which was consistent with the theoretical quantification limit of the CALUX. These results supported the validity of the proposed clean-up method. [ABSTRACT FROM AUTHOR]

To investigate the formation of mobile organic plutonium, we analyzed the plutonium contents of the fulvic (FA) and humic (HA) acids from the soil samples obtained at Nishiyama, Nagasaki, Japan. The percentages of the plutonium bound strongly to HA and to FA vs. the total plutonium in the soil were 5–10% and 1%, respectively, at the depth of 0–0.1 m, much higher values than those of137Cs and uranium. After being weathered for 51 years under a temperate climate, the initial highfired oxides of fallout plutonium have become as chemically reactive plutonium from nuclear fuel reprocessing plants. [ABSTRACT FROM AUTHOR]