Effect of zirconium oxide nanoparticles on thermal, optical, and radiation shielding properties of Bi2O3-B2O3-MnO2 glasses.

This study has explored the DSC, UV-Vis absorption spectroscopy, gamma ray and neutron shielding properties of Bi2O3-B2O3-MnO2: ZrO2 glasses. It demonstrates a unique approach to photon shielding analysis using JENDL/PD-2016 photonuclear data and employs a validated spherical neutron model for neutron shielding. Five transparent glasses were prepared with the chemical composition (in mol%) of 29Bi2O3-70B2O3-(1-x)MnO2: xZrO2, and labeled as MZ0.00 (for x = 0), MZ0.25 (for x = 0.25), MZ0.50 (for x = 0.5), MZ0.75 (for x = 0.75) and MZ1.00 (for x = 1). The glass ceramic nature of the samples has been characterized by DTA thermograms. The glass forming ability parameters (Kgl, S & H) were found to be highest for the sample MZ1.00. The UV-Visible optical absorption spectra have been interpreted, and hence the cut-off wavelength (λcut-off) and optical band gap (Eo) were evaluated. The absorption spectra have revealed the co-existence of manganese ions in three stable valence states Mn4+, Mn3+ and Mn2+ in the samples. When ZrO2 nanoparticles were added in the composition up to x = 0.50 mol%, the red shift in the cut-off wavelength (λcut-off) with gradual shrinkage in optical band gap (Eo) has been observed. Also, the linear and non-linear optical parameters viz., refractive index (no), non-linear refractive index (n2), linear optical susceptibility (χ(1)) and non-linear optical susceptibility (χ(3)) have been evaluated. These parameters showcased that B-O, Bi-O, Mn-O, Zr-O, etc. bonds could be strengthened by subsequent reduction of polarization of the trivalent ions (B3+ ions, Bi3+ ions and Mn3+ ions) in the glass system at higher concentrations of ZrO2. Photoatomic and photonuclear attenuation studies portrayed that the sample MZ0.50 has the lowest photon shielding capability. The fast neutron effective removal cross section (ΣR) was observed to be the highest for the sample MZ1.00. Thus, these glasses can be used to design the thermally stable transparent glasses, tunable optical elements, and radiation shielding materials.

Fatal re-expansion pulmonary oedema in a mechanically ventilated patient.

Fatal course of re-expansion pulmonary oedema (REPO) is infrequent and very rarely documented in mechanically ventilated patients. We report a case of fatal REPO following tube thoracostomy for a right-sided pneumothorax in an elderly patient of chronic obstructive pulmonary disease (COPD) with respiratory failure on mechanical ventilation.

Efficacy and tolerability of fixed-dose combination of simvastatin plus ezetimibe in patients with primary hypercholesterolemia: Results of a multicentric trial from India.

OBJECTIVE: To compare the efficacy and safety of fixed-dose combination (FDC) of simvastatin and ezetimibe vs simvastatin monotherapy in Indian patients with primary hypercholesterolemia. METHODS: This multicentric, double-blind, comparative, study conducted in India enrolled 230 patients with hypercholesterolemia (baseline low-density lipoprotein cholesterol [LDL-C] >120 mg/dL for patients on previous hypolipidemic drugs or >135 mg/dL for naïve subjects) were randomly assigned to receive either simvastatin (10 mg/day) or simvastatin (10 mg) plus ezetimibe (10 mg) FDC for 12 weeks. The primary efficacy endpoint was the mean percentage change in LDL-C from baseline to 12 weeks of therapy for simvastatin monotherapy vs simvastatin plus ezetimibe FDC. Secondary efficacy endpoints were mean percentage of changes in total cholesterol (TC), triglycerides (TG), and high-density lipoprotein cholesterol (HDL-C) from baseline to end of treatment, as well as proportion of patients achieving National Cholesterol Education Program Adult Treatment Panel III target LDL-C levels in each risk category. RESULTS: At the end of 12 weeks, the mean percentage reduction from baseline in LDL-C (-33.7%) was significantly greater with simvastatin and ezetimibe FDC compared to simvastatin alone (-26.28%, P < 0.05). Significantly greater percentage of patients (88%, P < 0.001) attained National Cholesterol Education Program Adult Treatment Panel III LDL-C target levels following ezetimibe/simvastatin treatment compared to simvastatin monotherapy (71%). Reductions in TG were significantly greater with ezetimibe/simvastatin than simvastatin (P < 0.001). Increases in HDL-C, and reduction in TC were similar between treatment groups. Safety and tolerability profiles were comparable for both treatments. CONCLUSION: Fixed-dose combination of simvastatin and ezetimibe provides a more effective means for reducing LDL cholesterol levels in Indian patients with hypercholesterolemia than simvastatin monotherapy without compromising the safety and tolerability profile.

Modeling the energy content of combustible ship-scrapping waste at Alang-Sosiya, India, using multiple regression analysis.

Alang-Sosiya is the largest ship-scrapping yard in the world, established in 1982. Every year an average of 171 ships having a mean weight of 2.10 x 10(6)(+/-7.82 x 10(5)) of light dead weight tonnage (LDT) being scrapped. Apart from scrapped metals, this yard generates a massive amount of combustible solid waste in the form of waste wood, plastic, insulation material, paper, glass wool, thermocol pieces (polyurethane foam material), sponge, oiled rope, cotton waste, rubber, etc. In this study multiple regression analysis was used to develop predictive models for energy content of combustible ship-scrapping solid wastes. The scope of work comprised qualitative and quantitative estimation of solid waste samples and performing a sequential selection procedure for isolating variables. Three regression models were developed to correlate the energy content (net calorific values (LHV)) with variables derived from material composition, proximate and ultimate analyses. The performance of these models for this particular waste complies well with the equations developed by other researchers (Dulong, Steuer, Scheurer-Kestner and Bento's) for estimating energy content of municipal solid waste.

Evaluation of the emission characteristics of trace metals from coal and fuel oil fired power plants and their fate during combustion.

Coal as well as fuel oil combustion generates emissions of potentially toxic trace pollutants including organic and inorganic chemical compounds besides major pollutants. A study on As, Cd, Co, Cr, Cu, Hg, Fe, Mn, Ni, Pb, Se, and Zn emissions from a 220 MW coal-fired power plant equipped with a electrostatic precipitators (ESPs) and 6 MW oil fired-power plant was carried out, using stack monitoring kit, Envirotech APM 620, which is similar to EPA Method 29. Simultaneous sampling of coal, fuel oil, oil waste, bottom ash, fly ash, flue gases, and particles associated with the gas phase has been performed. This sampling method was used for trace metal sampling. The content of all these metals in coal, oil, oil waste, bottom ash, fly ash have been determined by XRF, whereas their contents in the flue gases, and particles associated with the gas phase has been analyzed with ICP-AES. The mass balances obtained for trace elements were satisfactory in case of fuel oil based power plant, whereas in case of coal fired power plant, the mass balance for all the trace elements were below 50% except for the As, Se, and Hg. The enrichment factors for all trace metals was <1 in both cases. The above sampling method is moderately adequate method for trace element sampling in coal as well as oil fired power plants except for Hg. The results indicate that trace metals emissions were higher in coal-based power plant than the fuel oil-fired power plant.

Distribution, enrichment and accumulation of heavy metals in coastal sediments of Alang-Sosiya ship scrapping yard, India.

Since its inception in 1982, the Alang-Sosiya yard has become the largest ship scrapping works in the world. Several hundreds of ships arrive every year. The degree of heavy metal contamination has been studied in bulk and fine sediments from the intertidal zone of this ship scrapping yard, two stations, one on either side at 5 km distance and one reference station 60 km distance near Mahuva, towards the south. The samples have been subjected to a total digestion technique and analysed for elements: Cd, Co, Cu, Cr, Fe, Mn, Ni, Pb, Zn and Al, and %TOC. The absolute metal concentrations reflected variations in BF and FF sediment samples with organic matter content. Enrichment factors (EF) and geoaccumulation indices (Igeo) have been calculated and the relative contamination levels are assessed at these sites. At Alang-Sosiya, the enrichment of heavy metals has been observed to be relatively high.