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The present investigation aims to evaluate the feasibility of using Persea americana (Avocado) biodiesel in compression ignition engines. Persea americana bio-oil was extracted through a soxhlet extraction process using n-hexane solvent after careful pre-processing of the feedstocks. Since the Free Fatty Acid content was 1.78% estimated through titration, single stage base-catalyzed transesterification technique was adopted using methanol and sodium hydroxide as catalysts in the molar ratio of 1:6. Gas Chromatography-Mass Spectrometry analysis revealed the presence of Oleic acid in major proportions. The Fourier transform Infra-Red analysis confirmed the presence of carbonyl group ester ions between 722.19 cm-1 and 1460 cm-1. The 13C NMR and 1H NMR studies supported the successful transformation of triglycerides into Fatty Acid Methyl Esters with distinct peaks at 3.369 ppm and 48.147 ppm, respectively.

Azo dyes are well known recalcitrant and hazardous pollutants from dyeing industries which are essentially needed to be removed from the industrial effluents before discharged in the environment. Among many dye removal techniques, biosorption has gained attraction due to eco -friendliness and cost effectiveness. Biosorption of pollutant is surface phenomena which is resultant of the physicochemical interactions between biologically originated surfaces and the pollutant molecules. On the other hand, biomass from agro-industrial activities (e.g., rice straw, rice husk, wheat straw etc.) poses significant adversity on the environment, if traditional management practices are adopted. This study integrates the use of biomass for azo dye removal. It focusses on the utilization of rice straw biomass for removal of azo dye in the purview of sustainable environmental management. Biosorption of methylene blue dye (MB) by the use of rice straw and surface modified rice straw was studied. Rice straw powder (RSP) was treated with autoclaved sea water (RSP-ASW) and Sodium dithionite (RSP-SDT) and their characteristics was studied. Proximate analysis suggests the improvement in chemical composition by the treatments. The surface characterization with FTIR, PZC and SEM inferred the effect of modifying agents on RSP. Batch biosorption experiments were conducted to check the effect of operating parameters, viz., solution pH (pH3 -- pH11), temperature (298K-318K), initial dye concentration (50 mg/L-200 mg/L), contact time (0 -- 360 minutes), and adsorbent dosage (0.25 gm -1 gm) on MB removal. The preliminary investigations on sorption equilibrium of MB on pre-treated and untreated rice straw biomass showed the highest congruity with the Langmuir isotherm model, among the four adsorption isotherm models, viz., Freundlich, Langmuir, Temkin and DubininRadushkevich (D-R) isotherm models. The adsorption process follows the pseudo second order kinetics. The MB removal achieved was in the order RSPSDT> RSP-ASW>RSP in all the adsorption experiments conducted. The maximum dye removal efficiency was 181.8 mg of MB / gm of RSP-SDT at neutral pH and room temperature. [ABSTRACT FROM AUTHOR]

A new series of 1-(6-amino-3,5-dicyano-4-(substituted)pyridin-2-yl)-4-methylthiosemicarbazide derivatives 4(a–i) was achieved by the reaction of malononitrile and 4-methyl-3-thiosemicarbazide with various aldehydes. All the newly designed compounds were structurally established by various analytical methods (IR, 1H, 13C NMR, and HRMS). Further, all the entitled derivatives were evaluated for their potential antioxidant activity by DPPH radical method in which standard, ascorbic acid, was used for comparison and results revealed that the derivatives, 4a and 4i exhibited the highest antioxidant effect. [ABSTRACT FROM AUTHOR]

Background: Organophosphorus (OP) and carbamate pesticides are widely used for crop protection. We describe the spectrum of laryngeal abnormalities in patients admitted to the intensive care unit (ICU) with acute OP and carbamate poisoning as there is limited information on it. Materials and methods: Consecutive patients admitted to the ICU with acute OP and carbamate poisoning over 20 months (December 2014-July 2016) were recruited. Patients were followed up post-discharge if they had undergone tracheostomy or developed hoarseness of voice or stridor following extubation. Asymptomatic individuals who consented underwent laryngoscopy after ICU discharge. The primary outcome was the development of laryngeal dysfunction. Other outcomes included length of stay, need for ventilation, mortality, tracheostomy, and time to decannulation of tracheostomy. Results: Of the 136 patients recruited, 71 (52%) underwent laryngoscopy. The overall mortality rate was 9.6%. Of the 71 patients who underwent laryngoscopy, 18 had abnormal findings, which included unilateral or bilateral vocal cord paresis or palsy (n = 14) and/or aspiration (n = 9), subglottic stenosis (n = 1), tracheal stenosis (n = 1), or arytenoid granuloma (n = 1). Laryngeal dysfunction was associated with the ingestion of a dimethyl OP compound (p = 0.04) and quantum consumed (p <0.001). Patients with laryngeal dysfunction had significantly (p = 0.004) longer hospital stay (19.1 ± 10.7 vs 11.8 ± 8.3 days). Conclusion: Laryngeal dysfunction is not uncommon in OP and carbamate poisoning and is associated with the ingestion of larger quantity of a dimethyl OP compound and longer hospital stay. Otorhinolaryngologists could be involved early to help identify these abnormalities and initiate an appropriate treatment to ensure a functional voice and good airway. [ABSTRACT FROM AUTHOR]