Influence of temperature on thermo physical properties of non-prototype material (CaO-Fe2O3, 21:79 by wt. %) for nuclear reactor

165-173In severe accident management, the integrity of the containment structure is a key point to focus the study related to severe accident scenarios that need knowledge of thermo-physical properties of material composition. In the present nuclear accident scenario, nuclear severe accident management is one of the challenging tasks to mitigate the phenomena occurring inside the reactor pressure vessel (RPV). Numerous studies have been done in the past to predict the severe accident phenomena and tried to explore the incidence by using different prototype and non-prototype (simulant) materials. In this context, an initial effort has been made to study the actual phenomena during an accident scenario with non-prototype material CaO-Fe2O3. Initially, the present work involved the study of the material CaO-Fe2O3 powder for thermo-physical property analysis and later, the study will be carried out via melt cool ability of this material in a hypothetical nuclear reactor for analysis and mitigation of nuclear severe accident phenomena. The non-eutectic binary powder mixture of CaO and Fe2O3 has prepared manually by mixing in a mortar for 40 minutes in the ratio of 21:79 by wt. % (21C79F; C refers to CaO and F refers to Fe2O3) which has been confirmed by the phase diagram. Further, pallets were prepared of the non-eutectic binary mixture and heat-treated at 1000°C, 1100°C, and 1200°C for 3 hours in a programmable furnace. The powder form of heat-treated pellets was characterized to analyze thermo-physical properties and to validate as a simulant material (non-prototype) used for the predictive study of a nuclear severe accident. The thermal properties, phase analysis, and morphological studies of the CaO-Fe2O3 (21:79 by wt. %) have been reported in the current research work and analyzed accordingly

Prevalence and pattern of congenital heart diseases in Karimnagar, Andhra Pradesh, India: diagnosed clinically and by trans-thoracic-two-dimensional echocardiography

Background: To find the prevalence and pattern of congenital heart diseases (CHD) at a Semi-Urban teaching hospital in Karimnagar, Andhra Pradesh, India.Methods: A thorough history, clinical examination and Trans-Thoracic-Two-Dimensional Echocardiography (TTE) was done for all the live birth, children up to 18years of age and patients between 18 to 25 years, who were referred or presented to the Department of Medicine, Chalmeda Anand Rao Institute of Medical Sciences, Bommakal, Karimnagar (AP), over a period of 5 years from July 2008 through June 2013. Those suspected to having a CHD or referred in our department, were further evaluated with: Clinically, Twelve-Lead-Surface Electrocardiography, Chest Radiography and the diagnosis was confirmed by TTE. Trans-Thoracic-Two-Dimensional Echocardiography, M-Mode, Color flow doppler and Spectral doppler echocardiography was done in all patients in the various views.Results: Total 13,554 patients were examined and underwent TTE. Out of 13,554 patients 116 were identified as having congenital heart diseases, thus giving a prevalence of 8.55 per 1,000 live births. Isolated Ventricular septal defect (28.44%), isolated atrial septal defect (18.10%), Patent ductus arteriosus (10.34%), isolated congenital pulmonary stenosis (6.03%) and tetralogy of Fallot’s (6.03%), were the commonest defects observed and confirmed by TTE. TOF was the main cyanotic CHD (6.03%), with the prevalence of 0.51% per 1,000 live births. VSD, ASD and PDA were more prevalent in males. TOF and Complete A.V. Canal defect was prevalent in females. All small size muscular and perimembranous VSD was closed spontaneously. Spontaneous closure rate of 75.00% in Muscular VSD and 52.17% in perimembranous VSD was observed. Spontaneous closure rate of Ostium secundum type ASD was 53.33%. Conclusions: The prevalence of CHD at a tertiary teaching hospital (CAIMS, Bommakal, Karimnagar, AP, India), is 8.55 per 1,000 live births. VSD, ASD, PDA are the most common acyanotic and TOF was the commonest cyanotic congenital heart defects respectively. Non-Invasive Cardiac diagnostic technique (like TTE) plays major in the diagnosis of CHD. When clinical evidences lead to suspicion of congenital heart defect, an echocardiography should be performed immediately.