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[en] High-Tc copper oxides of the La2-xSrxCuO4 family show a very clear case of competition between antiferromagnetic order and superconductivity. Magnetic order can, however, coexist with superconductivity, and the experimental evidence for frozen magnetic moments in superconducting samples is reviewed here. The primary characteristics of the magnetic order are summarized and some open questions are outlined, particularly concerning the intrinsic or extrinsic nature of this order around x=0.12
Journal
[en] The criteria governing the choice of materials for the steam generators of sodium-cooled fast reactors concern: the mechanical properties at high temperatures, creep resistance and ductility at these temperatures and their variation with structural changes in the alloy; the possibilities of making and welding the various components (tubes, plates); corrosion resistance under normal conditions (clean water, steam and sodium) or in the event of accident (polluted media). Incoloy 800 has already been used to build prototypes including one of 45 MWth, installed on the Renardieres C.G.V.S.-E.D.F. Station. These prototypes, built with industrial products, have given satisfactory results after several thousand running hours. Research undertaken in particular by the Fives-Cail-Babcock Company and within the E.D.F./C.E.A. work program on fast reactor materials has led to recommended chemical composition and heat treatment limits and a manufacturing range giving optimum mechanical properties in service. The chemical composition chosen, the mechanical characteristics at room and high temperatures and results of welding and shaping experiments and of corrosion tests in various polluted media are presented
[fr]
Les differents criteres permettant le choix des materiaux destines aux generateurs de vapeur des reacteurs rapides refroidis au sodium portent sur: les caracteristiques mecaniques a chaud, resistance au fluage et ductibilite a chaud ainsi que leur variation en fonction de l'evolution structurale de l'alliage; la faisabilite des differents composants (tubes, plaques) ainsi que leur soudabilite; la resistance a la corrosion dans les conditions normales (eau, vapeur et sodium propres) ou accidentelles (milieux pollues). L'Incoloy 800 a deja ete utilise pour la realisation de prototypes dont un de 45 MW th, installe sur la Station du C.G.V.S. - E.D.F. Renardieres. Ces prototypes, realises a l'aide de produits industriels, ont donne des resultats satisfaisants apres plusieurs milliers d'heures de fonctionnement. Les etudes entreprises notamment par la Ste Fives-Cail-Babcook et dans le cadre du groupe de travail E.D.F./C.E.A. sur les materiaux des reacteurs rapides, ont conduit a preconiser des fourchettes de compositions chimiques et de traitement thermique, ainsi qu'une gamme de fabrication conduisant a une optimisation des caracteristiques mecaniques en service. La composition chimique retenue, les caracteristiques mecaniques a l'ambiante et a chaud, les realisations dans le domaine du soudage et du formage et les resultats de corrosion en divers milieux pollues sont presentesSource
Institut National des Sciences et Techniques Nucleaires (INSTN), Centre d'Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France); CEA Centre d'Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Dept. de Technologie; p. 535-554; ISBN 2727200072; 
; 1976; Institut National des Sciences et Techniques Nucleaires; Saclay, France; 18. Colloquium on metallurgy. Ni and its specific properties in certain types of alloys; Saclay, France; 23 Jun 1975
; 1976; Institut National des Sciences et Techniques Nucleaires; Saclay, France; 18. Colloquium on metallurgy. Ni and its specific properties in certain types of alloys; Saclay, France; 23 Jun 1975
[en] The study of pressure vessel accidents and degradation processes that lead to rupture is very useful to improve the reliability of vessels and accordingly that of nuclear boilers. The accident statistics are very insufficient in France, nevertheless it is possible to classify the accidents in categories and to determine the accident probability in each category. Some cases of accidents and ruptures are analyzed and two of them are particularly discussed
[fr]
L'etude des accidents des appareils a pression, et du processus de degradation qui mene a la rupture, est fort utile pour ameliorer la fiabilite de ces appareils et aussi, par voie de consequence, celle des chaudieres nucleaires. Bien que les statistiques d'accidents soient tres insuffisantes, surtout en France, on peut classer les accidents par categorie et avoir un ordre de grandeur du taux de probabilite de chaque categorie. Apres avoir analyse les accidents qui ont ete publies, ainsi que divers cas de rupture, la communication analyse plus en detail deux d'entre euxSource
Institut National des Sciences et Techniques Nucleaires (INSTN), Centre d'Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France); CEA Centre d'Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Dept. de Technologie; p. 11-57; ISBN 272720003X; ; 1975; Institut National des Sciences et Techniques Nucleaires; Saclay, France; 17. Colloquium on metallurgy. Mechanical and metallurgical factors of fracture, particularly in nuclear industry; Saclay, France; 24 Jun 1974
; 1975; Institut National des Sciences et Techniques Nucleaires; Saclay, France; 17. Colloquium on metallurgy. Mechanical and metallurgical factors of fracture, particularly in nuclear industry; Saclay, France; 24 Jun 1974
[en] Twenty-five patients with invasive adenocarcinoma of the rectum were treated by preoperative external irradiation (35 Gy), local excision, and peroperative placement of a plastic tube loop in the tumor bed for perioperative brachytherapy (20 or 25 Gy). Patients treated were too frail for radical resection (14 patients) or had refused a permanent colostomy (11 patients). With a mean follow-up of 40.5 months, there have been 5 patients with local relapse, 3 of whom had salvage abdominoperineal resections: 2 have no evidence of disease and 1 has developed distant metastatic disease. The 20 patients with local control have normally functioning sphincters; 1 has developed distant metastatic disease. This combined approach was designed to expand the curative role of local resection in carcinoma of the rectum. The surgical techniques are thoroughly described and the potential role and indications of this approach are discussed
Journal
[en] A total of 166 patients with large breast cancers (95 T2 and 71 T3) received pre-surgical external beam radiation therapy (45 Gy) with the goal of shrinking the tumor to a size that would allow tumor-ectomy. This goal was achieved in 45 % (75/166) of cases overall, 52% (49/95) of T2 tumors, and 37 % (26/71) of T3 tumors. In eight cases the tumor-ectomy specimen was free of residual tumor. No significant post-surgical complications were recorded. Eight patients (11%) had a local recurrence. The cosmetic result was acceptable in 96 % of cases. Pre-surgical radiation therapy allows to expand the indications of tumor-ectomy to many T2 and T3 breast cancers. (authors)
Journal
[en] The Superphenix steam generator is made of Alloy 800 tubing. The chemical composition of material is kept within narrow limits in order to obtain adequate corrosion behaviour, good mechanical properties and also good weldability. An automatic TIG orbital process has been adopted for the butt welds of the steam generator tubes using Inconel 82 filler metal and fabrication of butt welds is now in progress with the commercial process for Superphenix. (author)
Source
British Nuclear Energy Society, London; p. 51-54; ISBN 0 7277 0083 9; ; 1979; p. 51-54; British Nuclear Energy Society; London; Conference on welding and fabrication in the nuclear industry; London, UK; 3 - 5 Apr 1979
; 1979; p. 51-54; British Nuclear Energy Society; London; Conference on welding and fabrication in the nuclear industry; London, UK; 3 - 5 Apr 1979
[en] 44 patients with large tumors of the breast were treated with primary irradiation followed by various therapeutic modalities. Twenty-one patients received conventionally fractionated irradiation (CF) at 45 Gy and 23 low-dose rate radiotherapy (LDR), 12 patients at 45 Gy and 11 at 35 Gy. Tumor regression was estimated 3 months after beginning radiotherapy, whereas reactions in healthy tissue were observed at 6 months. In the CF group, tumor regression was complete in 19%, partial in 19% and poor in 62% of cases and the corresponding findings in the LD group were respectively 70, 30 and 0%. During the same follow-up period the pathological specimens obtained by incision biopsy were negative in 25% and positive in 75% of cases, whereas the corresponding results for LDR were respectively 64 and 36%. Cosmetic results in the CF group were good in almost all cases and no poor cases were found. In the LDR group, cosmetic results at 45 Gy were mediocre or poor in the majority of cases but good in all cases at 35 Gy. It is concluded that irradiation permits conservative treatment of large tumors of the breast in almost all cases. 35 Gy appears to be the optimal dose to obtain high tumor control with good cosmetic results
[fr]
Nous avons traite 44 cancers du sein evolues par teleradiotherapie premiere (suivie d'un complement therapeutique) dont 21 par fractionnement classique (FC) a la dose de 45 Gy et 23 cas par faible debit (FD) avec 12 cas a la dose de 45 Gy, puis 11 cas a la dose de 35 Gy. Le but de cette comparaison etait d'apprecier l'importance de la regression tumorale 3 mois apres le debut du traitement d'une part, d'observer les effets sur les tissus sains 6 mois apres le debut du traitement d'autre part. Avec le FC la regression tumorale etait totale dans 19% des cas, partielle dans 19% et nulle dans 62%; pour le FD les taux respectifs etaient de 70%, 30% et 0%. Histologiquement le controle biopsique dans le meme delai etait pour le FC negatif dans 25% des cas, positif dans 75%; pour le FD les taux respectifs etaient de 64% et de 36%. Sur le plan esthetique les resultats etaient pour le FC bons dans la majorite des cas et sans mauvais resultat; pour le FD les resultats a 45 Gy etaient mediocres ou mauvais dans la majorite des cas, bons dans la totalite des cas a 35 Gy. En conclusion, l'irradiation a faible debit permet de traiter les cancers du sein evolues de facon conservative dans la quasi-totalite des cas; la dose de 35 Gy par FD parait etre la dose optimale tant pour la tumeur (sterilisation) que pour les tissus sains (pas d'effet inesthetique)Journal
[en] Two heat treatment were studied for the prevention of structural retraction produced under service conditions with conventional tempering and revealed by an increase in stress during the relaxation tests. The observed results are discussed
[fr]
On a etudie deux traitements thermiques permettant d'eviter le retrait structural qui se produit en service avec le revenu habituel et qui se manifeste par une augmentation de la contrainte au cours de l'essai de relaxation. Les resultats observes sont interpretesJournal
Memoires Scientifiques de la Revue de Metallurgie; ISSN 0025-9128; ; v. 76(4); p. 241-252
; v. 76(4); p. 241-252
[en] Between 1980 and 1987, 25 patients with rectal cancer were treated with a combination of preoperative external irradiation of 35 Gy in 15 fractions over 3 weeks which was followed, 6 to 8 weeks later, by a tumorectomy and peroperative placement of a plastic tube loop for post-operative interstitial therapy by iridium-192. This boost dose was 20 Gy (Paris System) for submucosal lesions (seven patients) and 25 Gy for intramural (eight patients) and extramural (ten patients) lesions. With a mean follow-up of 40.5 months, there have been five local recurrences, the latest occurring 16 months post-tumorectomy. Two of these five patients are alive and disease-free 1 year post salvage abdominoperineal resection. The 20 patients with local control have preserved a full functional sphincter and 19 of them are disease-free; there were few complications. This sphincter preserving combined approach seems promising for patients with tumors of the middle and lower rectum who cannot undergo major surgery and for selected patients who refuse abdominoperineal resection
Journal
International Journal of Radiation Oncology, Biology and Physics; ISSN 0360-3016; ; CODEN IOBPD; v. 17(3); p. 539-545
; CODEN IOBPD; v. 17(3); p. 539-545
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