[en] An electron-curable, acryl-modified, epoxy coating composition having a high electron-curability and well balanced film properties is provided. It is prepared by reacting an acidic unsaturated polyester (A) which an epoxy resin (B) and an α,β-olefine acid (C) and dissolving the resulting product into a vinyl monomer (D). Preferably, (A) contains, in its molecule, the ethylenic units not at random but block-wise which is useful in obtaining a higher electron-curability and a higher impact strength of film. In one example, 1.0 mole of propylene glycol was reacted with 0.5 mole of fumaric acid and the product was reacted with 0.7 mole of phthalic anhydride to give (A). 1 mole of (A) was reacted with 0.3 mole of Epikote 1004, 0.5 mole of Epikote 1001, 0.4 mole of Epikote 828 and 0.3 mole of Epikote 872. The product was reacted with 3.0 moles of methacrylic acid to give an acryl-modified epoxy resin. The latter was dissolved into a mixture of styrene, ethyl acrylate and methyl methacrylate (0.3:0.2:0.5 by wt.). A ground steel board was coated with the resulting composition and irradiated with electron beams (total dose 4 Mrad, conveyer speed 3.4 m/min.). Properties of the cured film were as follows: impact strength, good; resistances to solvents, good; pencil hardness, 2H; Erichsen test, 8 mm; tensile strength 7.7 kg/mm²; elongation 7.8%. (Kaichi, S.)

[en] Purpose: To prevent stress corrosion cracks in reactor structural materials by injecting hydrogen in the reactor water to suppress oxygen produced in the reactor upon usual operation of a BWR type reactor. Constitution: A potential measuring probe for measuring the potential of fluid is provided to the circuit of clean up system by-passing a reactor. When the potential obtained from the potential measuring probe is higher than a predetermined potential of a potential measuring device, the difference is calculated and the calculated signal is given to a flow rate control valve disposed at the inlet of the reactor for feeding hydrogen. Then, hydrogen is injected so as to keep the corrosion potential for the reactor structural materials to less than -300 mV of hydrogen electrode potential reference, whereby grain boundary type stress corrosion cracks can be suppressed in the reactor structural materials. (Aizawa, K.)

[en] The plant of the present invention can suppress the amount of clad in feedwater when drains of a moisture content separation heater or a high pressure feedwater heater are recovered. That is, the moisture content separation heater has ferrite or austenite type stainless steel heat transfer pipes. A chromium-enriched layer is formed on the surface of the heat transfer pipe by chromizing treatment or flame spraying. Then, a stainless steel heat transfer pipe having chromium-enriched layer is incorporated to at least one of the moisture content separation heater or the high pressure feedwater heater. During plant operation, the temperature of heated steams is as high as 235 to 282degC. Accordingly, this is a severe corrosion region for ferrite or austenite stainless steel. However, the chromium-enriched layer of excellent corrosion resistance is formed on the surface of the heat transfer pipe. Accordingly, metal ingredients are less leached. As a result, even if the drains are recovered to feedwater, increase of concentration of the clads in the feedwater can be prevented. (I.S.)

[en] Purpose: To enable to prepare solidified products with no deleterious pores and least free water content as possible while avoiding the problem of secondary wastes treatment. Method: Cement mortar or paste with an addition of a mixing agent for the improvement of fluidity is injected into a vessel containing radioactive incombustible solid wastes and the mortar or paste is filled in the gap of wastes and solidified by applying vibrations to the vessel. Thus, when the radioactive incombustible solid wastes are solidified with cement in accordance with the solidification processes, contained in a drum can or like other vessel can be solidified as they are with no requirement for a mixer, etc. Accordingly, no installation cost is required and there is no problems such as processing of washing water. (Yoshihara, H.)

No abstract available

[en] Applying 3D nonlinear MHD simulation codes, the magnetic island and its interaction with the MHD activities are studied in the Large Helical Device (LHD) experiment. In an experiment, the collapse in the plasma core was observed in a configuration, which has large magnetic island produced by an intrinsic error field. At the collapse, the temperature profile was flattened. This suggests the magnetic island evolved. The magnetic island was observed by the magnetic diagnostics. The magnetic diagnostics also suggests evolving the magnetic island. 3D MHD equilibria are calculated by the 3D MHD equilibrium code then nonlinear MHD are simulated. Since the comparison of observed and calculated results is comparable, the magnetic island in calculated results is similar to one of the experiment. (author)

[en] Three-dimensional computed tomography angiography (3D-CTA) was compared with digital subtraction angiography (DSA) for the delineation of the skull base venous system in presurgical planning of the subtemporal approach in 201 sides of 109 patients. The axial stereoscopic images and multi-projection images were used in 3D-CTA, and the anteroposterior views and lateral views were used in DSA. DSA showed that the vein of Labbe (VL) was the most common venous flow on the lateral or basal surface of the temporal lobe, whereas 3D-CTA demonstrated that the involvement of the temporo-basal vein (TBV) was equal to that of VL in frequency. 3D-CTA showed that the VL flowed into the transverse sinus (TS) on 132 sides, the sigmoid sinus-TS junction on 29 sides, and the lateral tentorial sinus (LTS) on 40 sides. DSA showed that the VL flowed into the TS on 157 sides and into the LTS only on 5 sides. DSA showed that the TBV flowed into the TS on 37 sides but axial 3D-CTA showed that the TBV flowed into the LTS on 48 sides. This inconsistency reflects the difficulty in confirming and identifying these veins on the anteroposterior view of DSA, due to the overlapping of veins and poor delineation. Axial stereo and multi-projection images of 3D-CTA provided practical images of the deep veins of the skull base venous system and showed the relative anatomical relationships of the arteries and bony structures. This information can specify the venous inflow point, and help to determine the direction of approach and working space, and also help to identify intraoperative landmarks for the subtemporal approach. Presurgical examination of the deep venous system with 3D-CTA may help to minimize unexpected injury to veins and venous infarction. (author)

[en] The variations of superficial middle cerebral vein (SMCV) were evaluated by the use of 3D-CTA. 3D-CTA is useful to confirm the situation, inflow point and anatomical relationship with the middle cranual fossa bone structures. It delineated the veins clearly and dramatically to run middle cranial fossa and to flow into sphenoid emissary vein, transverse sinus or superior petrosal sinus. 3D-CTA enabled us to classify the variation of SMCV more clearly and reasonably. (author)

[en] Low-level liquid waste containing sodium nitrate is planned to be transformed to salt block by evaporation with sodium borate in the Low-level Waste Treatment Facility (LWTF), then salt block will be stored temporally. It should be important to investigate the method how to treat these liquid waste suitable to final disposal criteria that will be settled in future. Cement solidification is one of promising candidates because it has been achieved as the solidification material for the shallow land disposal. The research was conducted to evaluate applicability of various cement materials to solidification of sodium nitrate. The following cements were tested. Ordinary Portland Cement (OPC). Portland Blast-furnace Slag Cement; C type (PBFSC). Alkali Activated Slag Cement (AASC, supplied by JGC). The test results are as follows; (1) AASC is characterized by a high sodium nitrate loading (-70 wt%) compared with other types of cement material. High fluidity of the cement paste, high strength after solidification, and minimization of free water on the cement paste are achieved under all test conditions. (2) OOPC and PBFSC produced free water on the cement paste in the early days and delayed the hardening period. 3 or more days are required to harden evan with 30 wt% content of sodium nitrate. (3) Though PBFSC contains blast furnace slag similar to AASC, there is no advantage prior to OPC. To design an ideal cement conditioning system for sodium nitrate liquid waste in the LWTF, the further studies are necessary such as the simulated waste test, Kd test, pilot test, and layout design. (author)

[en] Nonlinear dynamics in Heliotron plasmas using a 3D nonlinear MHD simulation code in heliotron plasmas is studied. In the Large Helical Device (LHD) experiment, many MHD instabilities are observed. Especially, if the peaked pressure profile was sustained by the pellet injection, a collapse event, so-called the core density collapse (CDC), was happen. In nonlinear MHD simulations, it is expected the CDC is driven by the resistive ballooning mode. Recently, a new imaging diagnostics of the two-dimensional soft-X ray arrays is installed in the LHD. Using the new diagnostics, perturbations localized at the outward of the torus. That is a characteristic of the ballooning mode. So, it seems the ballooning mode is observed in the LHD experiments. However, to interpret the experimental observation, we need to know what kind mode patterns should be observed. In this study, we study 3D MHD equilibria with reconstructed pressure profile using a 3D MHD equilibrium code, which does not assume nested flux surfaces. And then, we will study nonlinear MHD simulations based on the 3D MHD equilibrium with the magnetic island. In this study, we note nonlinear saturation to compare with the experimental observation. (author)