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[en] After several PWSCCs were found in Bugey(France), Ringhals(Sweden), Tihange(Belgium), Oconee, Arkansas, Crystal Fever, Davis-Basse, VC Summer(U.S.A.), Thuruga(Japan), USNRC and PNNL started the research on PWSCC, that is, PINC project. The aim of this project is to fabricate and obtain representative NDE mock-ups with flaws to simulate tight PWSCC cracks, to identify and quantitatively assess NDE methods for accurately detecting, sizing and characterizing tight cracks such as PWSCC, to document the range of locations and crack morphologies associated with PWSCC and observed responses and to incorporate findings from other ongoing PWSCC research programs, as appropriate. By participating in PINC project, Korean morphology technique about PWSCC and NDE technique have improved and become similar lever with other advanced country. Therefore, the evaluation technique of integrity for nickel alloy component has been improved by cooperation with university, research institute and industries.
[en] NiCu alloys have been suggested as potential candidates for catalysts in glucose oxidation. In this study, NiCu alloys with different compositions were prepared on a glassy carbon substrate by changing the electrodeposition potential to examine the effect of Ni/Cu ratios in alloys on catalytic activity toward glucose oxidation. Cyclic voltammetry and chronoamperometry showed that NiCu alloys had higher catalytic activity than pure Ni and Cu catalysts. Especially, Ni59Cu41 had superior catalytic activity, which was about twice that of Ni at a given oxidation potential. X-ray analyses showed that the oxidation state of Ni in NiCu alloys was increased with the content of Cu by lattice expansion. Ni components in alloys with higher oxidation state were more effective in the oxidation of glucose
[en] One of wide-spread method of different materials joint is diffusion welding. It has being brought off at the expense of mutual diffusion of atoms of contacting surfaces under long-duration curing at its heating and compression. Welding regime in dependence from properties of welding details is defining of three parameters: temperature, pressure, time. Problem of diffusion welding optimization concludes in determination less values of these parameters, complying with requirements for quality of welded joint. In the work experiments on diffusion welding for calculated temperature and for given surface's roughness were carried out. Tests conduct on samples of iron and iron-nickel alloy with size 1·1·1 cm3. Optimal regime of diffusion welding of examined samples in vacuum is defined. It includes compression of welding samples, heating, isothermal holding at temperature 650 deg C during 0.5 h and affords the required homogeneity of joint
[en] Self-expanding metallic stent insertion has been widely applied for the palliative treatment of malignant esophageal strictures. Although it is known as an easy, safe, and effective procedure, complications are well known and include things such as stent migration and esophageal stent occlusion caused by tumor in growth. However, metallic stent fractures have been rarely reported in the esophagus, especially for nitinol stents. We report a case of a stent fracture associated with migration in a patient with a malignant esophageal stricture near the gastroesophageal junction. It is highly probable that the stent fracture was due to chemical erosion of the stent caused by gastric juice
[en] The performance of equipment are limited by the materials employed, they are submitted to extreme conditions and safety criteria are very severe. Are more particularly studied: the choice and the fabrication of nickel alloys for steam generator tubes of water reactors, stainless steels used in superphenix and briefly the stainless steel Uranus S1N for reprocessing facilities because of its outstanding resistance to oxidizing media
[fr]Les performances des equipements ont des limites dues aux materiaux qui sont soumis a des conditions extremes et les conditions de securite sont tres severes. On etudie plus particulierement le choix et la fabrication d'alliages de nickel pour les tubes de generateurs de vapeur des reacteurs a eau, les aciers inoxydables utilises pour Superphenix et tres brievement l'acier inoxydable Uranus S1N utilise dans les installations de retraitement grace a sa bonne resistance en milieu tres oxydant
[en] After several damages by PWSCC were found in the world, USNRC and PNNL(Pacific Northwest National Laboratory) started the research on PWSCC under the project name of PINC. The aim of the project was 1) to fabricate representative NDE mock-ups with flaws to simulate PWSCCs, 2) to identify and quantitatively assess NDE methods for accurately detecting, sizing and characterizing PWSCCs, 3) to document the range of locations and morphologies of PWSCCs and 4) to incorporate results with other results of ongoing PWSCC research programs, as appropriate. Korea nuclear industries have also been participating in the project. Thermally and mechanically cracked-four mockups were prepared and phased array and manual ultrasonic testing(UT) techniques were applied. The results and lessons learned from the preliminary RRT are summarized as follows: 1) Korea RRT teams performed the RRT successfully. 2) Crack detection probability of the participating organizations was an average 87%, 80% and 80% respectively. 3) RMS error of the crack sizing showed comparatively good results. 4) The lessons learned may be helpful to perform the PINC RRT and PSI /ISI in Korea in the future.
[en] Methods of contrast and electron-microscope autoradiography were used to study 3H distribution in XH55MBYu alloy. The mathematical treatment of autoradiograms is shown that majority of hydrogen atoms segregate on interphase boundaries. (author). 9 refs, 3 figs
[en] After several PWSCCs were found in Bugey(France), Oconee, Arkansas, Crystal Fever, Davis-Basse(U.S.A.), USNRC and PNNL started the research on PWSCC, that is, PINC project. The aim of this project is to fabricate and obtain representative NDE mock-ups with flaws to simulate tight PWSCC cracks, to identify and quantitatively assess NDE methods for accurately detecting, sizing and characterizing tight cracks such as PWSCC, to document the range of locations and crack morphologies associated with PWSCC and observed responses and to incorporate findings from other ongoing PWSCC research programs, as appropriate For this aim, PINC group was organized by three task groups. Task group 1 is Morphology Atlas (TG-Atlas) group. Task group 2 is NDE Technology Assessment (TG-NDE) group. Task group 3 is Data Analysis group (DAG). USNRC required KINS to participate in PINC project at May 2005. KINS consists Korean consortium which includes KINS, KAERI, KHNP and SKKU at March 2006 and Pre RRT for RVHP and DMW were performed for the preparation of PINC RRT and presented at PINC meeting. PINC DMW RRT has been performed since 2006 August and Japan and Europe finished their RRT. DMW RRT has performed between 2007 June and September in Korea. Korea RRT result was sent to USNRC and PNNL to evaluate result
[en] We wanted to evaluate the long-term results of a dual expandable nitinol stent for the palliative treatment of malignant gastroduodenal strictures. The dual stent consists of two stents; an outer partially nylon covered stent and an inner bare nitinol stent. The outer stent was placed into the stricture and this was followed by coaxial placement of the inner bare stent. Using fluoroscopic guidance, dual expandable stents were placed in 86 patients with inoperable malignant gastroduodenal strictures. The technical and clinical success, the complication, survival and the stent patency were evaluated during the follow-up period. Stent placement was technically successful in 83 of the 86 patients. After stent placement, 74 of the 85 patients showed improvement of their symptoms. During the mean follow-up period of 133 days, 24 patients (28%) developed recurrent symptoms due to incomplete expansion (n=1), stent migration (n=4), food impaction (n=2), granulation tissue formation (n=2), tumor overgrowth (n=6), tumor ingrowth (n=1) and stent collapse (n=8). Eleven of them were successfully treated by means of placing a second stent. The median period of stent patency was 212 days (mean, 299 days). The 30-day, 60-day, 90-day and 180-day patency rates were 93%, 84%, 81% and 53%, respectively. The dual expandable nitinol stent seems to be effective for the palliation of malignant gastroduodenal strictures