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Introduction: The challenge in restorative dentistry is related to changes in the colour of composite over time when exposed to a variety of common beverages, which necessitates additional expenses for the patients. Aim: To compare the colour changes of various composites currently available on the market after exposure to commonly consumed beverages. Materials and Methods: This in-vitro study was conducted from May 2022 to December 2022 in the Department of Conservative Dentistry and Endodontics at Karnavati School of Dentistry in Gandhinagar, Gujarat, India. A total of 120 disc-shaped composite pellets, with 40 specimens for each type of composite (nanohybrid, nanofilled, and microhybrid), measuring 6×2 mm, were prepared and divided into four subgroups based on the beverages used (Distilled water, coca-cola, Tea, and Coffee). The samples were submerged in the respective beverages and kept at 37°C for seven days. Colour assessment was performed using a spectrophotometer before and after immersion. The obtained Commission International de l Eclairage (CIE) ΔE values were recorded after measuring the CIE L*a*b* values. Data analysis was conducted using Statistical Package for Social Sciences (SPSS) software version 20.0, utilising a paired t-test, post hoc Tukey's test, and one-way Analysis of Variance (ANOVA). A significance level of p<0.05 was used. Result: Among all the beverages, the nanofilled composite showed the highest mean colour change, while the nanohybrid composite exhibited the lowest. Overall, the greatest colour change was observed with tea, followed by coffee, coca-cola, and the least with distilled water. In tea, coffee, and cocacola, the nanohybrid composite and nanofilled composite showed a statistically significant difference in mean colour change: 16.74 (p<0.001), -7.29 (p<0.001), and -1.02 (p=0.018), respectively. However, the difference between the nanohybrid and microhybrid composite was statistically insignificant. Conclusion: The nanohybrid composite demonstrated the least mean colour change, followed by the microhybrid composite, while the nanofilled composite exhibited the highest colour change. [ABSTRACT FROM AUTHOR]

To deal with the rising demand of fossil fuels and their associated untoward environmental and economic effects, the feasibility of Indian government's green move towards blending of 20% fuel grade ethanol with gasoline has been studied by performing techno-economic-environmental analysis of second generation lignocellulose biomass as feedstock. An optimized supply chain network (SCN) has been designed with four layers of structure starting from raw material suppliers to the retailers through the layers of the manufacturers and the distributors aiming at the net present value (NPV) maximization. The cost calculation includes operating expenditure (OPEX) and capital expenditure (CAPEX) components involving transport, storage, production and import decisions as linear variables and decisions on connections between two nodes between two consecutive layers as binary variables. The distribution layer of the mixed integer linear programming (MILP) model has been uniquely designed for the imported ethanol to serve the twin purposes of meeting the unmet demand as well as enhancing the bio-ethanol product quality in terms of research octane number. The revenue generation is calculated not only from selling the final product but also from the carbon credits calculated using greenhouse gas emission (GHGe) during project life cycle assessment. Further, sensitivity analysis has been performed to show the effect of various parameters such as modes of transport, transport distance limitation on feedstock and product, number of zones, international fuel price fluctuations, feedstock availability on NPV. With ∼80% increase in demand over the 9-year planning horizon, a dynamically changing supply chain (SC) structure shows a ∼36% increase in the newly added locations. Feed availability, critical for Indian scenario, to the tune of at least 40% of the capacity is needed to meet the projected demands. Image 1 • MILP frame work for NPV using newly implemented goods and service tax (GST). • Decentralized model zones based on population data and feed type availability. • Blending indigenous bioethanol and imported ethanol for desired RON quality. • Revenue generation from greenhouse gas emission (GHGe) savings as carbon credits. • Sensitivity analysis of distance, international price and feed availability on NPV. [ABSTRACT FROM AUTHOR]

Utility and industrial steam generators in India are designed to burn coal for generating electricity, due to coal availability and economy. Rapid increase in coal-fired power projects increased the gap in demand and supply and therefore necessitated using available coals rather than plant design coal. Studies in different capacity boilers using coals of varying properties like gross calorific value, fixed carbon, volatile, moisture and mineral matter up to 100% in gross calorific value and 200% in mineral matter more than that of designed coal has been conducted. Performances of boilers were different than predicted due to variations in the fuel characteristics. [ABSTRACT FROM PUBLISHER]