Ductile iron （DI） is a preferred material for use in various structural, automotive, and engineering fields because of its excellent combination of strength, toughness, and ductility. In the current investigation, w...Ductile iron （DI） is a preferred material for use in various structural, automotive, and engineering fields because of its excellent combination of strength, toughness, and ductility. In the current investigation, we elucidate the relationship between the morphological and mechanical properties of DI intended for use in safety applications in the nuclear industry. DI specimens with various alloying elements were subjected to annealing and austempering heat treatment processes. A faster cooling rate appeared to increase the nodule count in austempered specimens, compensating for their nodularity value and subsequently decreasing their ductility and impact strength. The ductility and impact energy values of annealed specimens increased with increasing ferrite area fraction and nodularity, whereas an increase in the amounts of Ni and Cr resulted in an increase of hardness via solid solution strengthening. Austempered specimens were observed to be stronger than an- nealed specimens and failed in a somewhat brittle manner characterized by a river pattern, whereas the ductile failure mode was character- ized by the presence of dimples.展开更多
The environmental fate, global warming effect and human health risk from mono aromatic VOCs are of major concerns among many consequences of their anthropogenic emission. In more than a yearlong study (November 2003 t...The environmental fate, global warming effect and human health risk from mono aromatic VOCs are of major concerns among many consequences of their anthropogenic emission. In more than a yearlong study (November 2003 to February 2005) of the city air in Kolkata, India at different seasons in three different sites, the seasonal mean benzene and toluene concentrations varied between 13.8–72.0 μg/m3 and 21.0–83.2 μg/m3 respectively along all the sites. The environmental distribution and load of BTEX (Benzene, Toluene, Ethylbenzene and isomers of Xylene) in different environmental compartment was estimated using a multimedia mass balance model, TaPL3. The total environmental load of BTEX together was estimated to be 9.7 × 104 kg. Contribution of Kolkata metropolitan city towards global warming due to environmental emission of BTEX has been estimated as 1.9 × 105 tons of carbon dioxide equivalent per year which is about 1.1% of yearly direct CO2 emission the city. The consequence of BTEX emission towards human health has been estimated in terms of non-cancer and cancer risk in population due to their inhalation exposure. The cumulative lifetime cancer risk for benzene and ethylbenzene was found to be higher than the acceptable value and range between 3.0 × 105 and 8.9 × 106 in three sites, although the non-cancer health risk was found to be within acceptable limit.展开更多
基金the Board of Research in Nuclear Science (Project Grant No. 2011/36/18-BRNS), India for carrying out this investigation
文摘Ductile iron （DI） is a preferred material for use in various structural, automotive, and engineering fields because of its excellent combination of strength, toughness, and ductility. In the current investigation, we elucidate the relationship between the morphological and mechanical properties of DI intended for use in safety applications in the nuclear industry. DI specimens with various alloying elements were subjected to annealing and austempering heat treatment processes. A faster cooling rate appeared to increase the nodule count in austempered specimens, compensating for their nodularity value and subsequently decreasing their ductility and impact strength. The ductility and impact energy values of annealed specimens increased with increasing ferrite area fraction and nodularity, whereas an increase in the amounts of Ni and Cr resulted in an increase of hardness via solid solution strengthening. Austempered specimens were observed to be stronger than an- nealed specimens and failed in a somewhat brittle manner characterized by a river pattern, whereas the ductile failure mode was character- ized by the presence of dimples.
文摘The environmental fate, global warming effect and human health risk from mono aromatic VOCs are of major concerns among many consequences of their anthropogenic emission. In more than a yearlong study (November 2003 to February 2005) of the city air in Kolkata, India at different seasons in three different sites, the seasonal mean benzene and toluene concentrations varied between 13.8–72.0 μg/m3 and 21.0–83.2 μg/m3 respectively along all the sites. The environmental distribution and load of BTEX (Benzene, Toluene, Ethylbenzene and isomers of Xylene) in different environmental compartment was estimated using a multimedia mass balance model, TaPL3. The total environmental load of BTEX together was estimated to be 9.7 × 104 kg. Contribution of Kolkata metropolitan city towards global warming due to environmental emission of BTEX has been estimated as 1.9 × 105 tons of carbon dioxide equivalent per year which is about 1.1% of yearly direct CO2 emission the city. The consequence of BTEX emission towards human health has been estimated in terms of non-cancer and cancer risk in population due to their inhalation exposure. The cumulative lifetime cancer risk for benzene and ethylbenzene was found to be higher than the acceptable value and range between 3.0 × 105 and 8.9 × 106 in three sites, although the non-cancer health risk was found to be within acceptable limit.
