Journal Articles - Engineering Technology - 2023
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PublicationInfluences of diols and nonionic hydrotrope on the aggregation and physico-chemical properties of sodium dodecyl sulfate and polyvinyl alcohol mixture at numerous experimental temperatures( 2023)"This study investigates the interaction between sodium dodecyl sulfate (SDS) and polyvinyl alcohol (PVA) in the presence of additives (ethylene glycol (EG), propylene glycol (PG), 2,3-butanediol (2,3-BD), and resorcinol). The critical micelle concentration (CMC) of the surfactant system was estimated by using the conductometric tech nique. The influence of temperature, concentration, and additive composition on the physicochemical variables (CMC, micelle ionization (α) and counter ion binding (β)) were also investigated. The observed variation in CMC was attributed to several factors, such as the concentration of additives, the nature of hydrophobicity, and the magnitude of the dielectric constant of the mixed solvents. The CMC of the SDS + PVA mixed system was increased with increasing temperature due to the dominance of hydrophobic hydration over the hydrophilic one. The evaluation of thermodynamic parameters, such as change in standard Gibbs free energy (ΔGo m), enthalpy (ΔHo m), and entropy (ΔSo m) and the estimation of β value for the SDS + PVA mixed system indicate the feasibility and viability of the micelle formation. The negative values of ΔGo m observed within the temperature range of 298.15 to 323.15 K suggest a favorable condition for the formation of surfactant micelle. The that the binding forces in the SDS + PVA mixed system are hydrophobic and ion–dipole interactions in nature. The investigation of the intrinsic enthalpy (ΔH0,* m ) determines the stability of the surfactant system, while the compensation temperature (Tc) serves as an indicator of the solute-solvent interaction."
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PublicationEffects of green extraction solvents on phenolic contents and bioactivities of Persicaria odorata (Lour.) Sojak( 2023)Persicaria odorata (Lour.) Sojak is one of the widely consumed herbs in Southeast Asian countries. It is a popular culinary ingredient in many Asian dishes in part due to its unique pungent flavor. This study aimed to determine phenolics, antioxidant, potential anti-inflammatory activities and inhibition of -glucosidase of P. odorata extracts obtained with ethanol (ET), 80% ethanol (EW) and water (AQ). These extractants had influences on the presence of phytochemical groups (i.e., alkaloids, saponins, tannins and triterpenoids), phenolic contents and bioactivities in the extracts obtained. The 80% ethanol extract had the highest total contents of phenolics (207.59 +/- 14.32 mg GAE/g) and flavonoids (126.00 +/- 7.07 mg QE/g). All the phenolics examined were present in ET and EW while half of them were detected in AQ. The extracts prepared with ethanol and 80% ethanol in general exerted higher antioxidant activity. In addition, ET and EW exhibited the stronger inhibitory effect on alpha-glucosidase (2.44 +/- 0.12 and 2.20 +/- 0.08 mmol ACAE/g, respectively). With respect to in vitro anti-inflammatory activity, ET showed an inhibitory effect against albumin denaturation comparable with that of the 200 ug/mL diclofenac solution. The study provides a better understanding of phytochemicals and potential health endorsing properties of P. odorata, which is helpful for design of new naturally occurring agents for disease prevention and treatment.
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PublicationDoes eco-innovation and green investment limit the CO2 emissions in China?( 2023)The continuous upsurge in worldwide economic development and human activities has intensified CO2 emissions that highlighted the significant role of eco-innovation and green investment in curbing CO2 emissions. The study aims to explore the impact of eco-innovation and green investment on CO2 emissions by using the China dataset for time period 1990–2019. The study adopts the ARDL approach. The study used two proxies to determine the impact of eco-innovation, namely environment-related technologies and patents. The empirical estimates of the ARDL approach confirm the negative impact of eco-innovation and green investment on CO2 emissions confirming that these determinants result in limiting CO2 emissions in China. Based on these findings, the study suggests strengthening environmentally friendly policies and the advancement of green investment to mitigate CO2 emissions.
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PublicationImpact of eco-innovation and sustainable tourism growth on the environmental degradation: the case of China( 2023)Climate complexities and global warming have made sustainable development a customary topic in environmental literature. Since then, various diggings have been happening in academia. Amongst them tourism and eco-innovation receives the heap due to its contribution to economic development. The study, thereby, examines the impact of tourism, economic growth and eco-innovation on environmental degradation in China. The secondary data has been extracted from World Development Indicators (WDI) database from 1988 to 2020. The nexus among the variables have been examined using Nonlinear Autoregressive Distributed Lagged (NARDL) model. Findings reveal that international tourism receipts, expenditures and number of tourist arrival, GDP, national income and inflation are positively correlated with environmental degradation, while sustainability- oriented eco-innovation is related negatively in case of China. This study has provided help to the regulators while developing new policies regarding environmental degradation by controlling emissions from economic and tourism development and using sustainability- oriented eco-innovation.