A series of experiments were conducted along with the calculation of hydrogen distribution within the specimen, in order to define the microscopical critical condition for initiation of disbonding in the austenitic stainless weld overlaid 21/4Cr-1 Mo steel. The experiments consist of observation of acoustic emission, analysis of hydrogen concentration in the interface zone, electrolytical charging o f hydrogen while major experiments were run by gas charging in autoclaves, and utilization of large-sized test blocks.Resultant major conclusions were that (1) disbonding is caused only by the effect of accumulated hydrogen on the cladding near the interface between cladding and the base metal under coexistence o f residual thermal stress, i.e., holding a specimen in high temperature hydrogen is not a necessary condition for disbonding, and (2) the microscopical critical condition for initiation of disbonding for a standard type of weld overlaid specimen is the calculated hydrogen concentration in cladding about 50μm apart from the interface to reach about 170ppm.
An 82-year-old male patient was admitted for liver dysfunction. Laboratory test showed the following data; aspartate aminotransferase (AST) 79 IU/l, alanine aminotransferase (ALT) 28 IU/l, total bilirubin (T. Bil) 0.9 U, zinc sulfate turbidity test (ZTT) 48.9 U, gamma-globulin 4.9 g/dl, immunoglobulin G (IgG) 5,046 mg/dl, anti-nuclear antibodies x 320, anti-mitochondrial antibodies (-), hepatitis B virus surface antigen (HBsAg) (-), HBcAb (-), anti-hepatitis C virus (anti-HCV) (-), hepatitis C virus (HCV-RNA) (-), anti-hepatitis G virus (anti-HGV) (-), alpha-fetoprotein 306.8 ng/ml, carcinoembryonic antigen (CEA) 2.3 ng/ml, carbohydrate antigen (CA) 19-9 77.2 U/ml. Abdominal ultrasonography and computed tomography showed a large mass occupying most of the right lobe and portal thrombosis in the liver. Liver biopsy revealed cirrhosis with inactive hepatitis in the nontumorous lesion and well-differentiated hepatocellular carcinoma in the tumorous lesion. We report a rare case of an aged male patient with autoimmune hepatitis complicated by hepatocellular carcinoma.
