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The main objective of this research is to investigate, experimentally, the effects of biodiesel blends on the performance and emissions of a Diesel engine. Measurements were carried out on a single-cylinder, four-stroke, and air-cooled compression-ignition engine, under half and full load conditions. Engine speed was varied from 1000-3000 rpm. Biodiesel was produced by transesterification process of sunflower oil with ethanol, using microwave-assisted heating reactor. Three biodiesel-diesel mixtures: containing 5%, 10%, and 20% by volume of biodiesel, respectively, have been tested and compared to pure diesel fuel. The effects of these biodiesel blends on the engine operating characteristics such as brake specific fuel consumption, brake power, brake thermal efficiency, brake mean effective pressure, and on carbon CO, CO2, and NOx emissions, have been investigated. It was noticed that, at full load, the specific fuel consumptions of biodiesel blends were higher compared to the pure diesel fuel, but no change was observed under ½ load. An improvement in the brake thermal efficiency, under ½ load, was obtained, but at full load, for medium and high speed, the thermal efficiencies of all biodiesel blends showed a decrease compared to pure diesel fuel. Concerning pollutants emissions, a decrease in CO emissions of all biodiesel blends was noticed. The best result in CO emissions was achieved by the mixture containing 10% by volume of biodiesel with an average reduction value close to 40%. In addition, a significant reduction in NOx emissions was observed for the three biodiesel blends. [ABSTRACT FROM AUTHOR]

3-hydroxy-3-methylglutaryl-CoA reductase (HMGR), as the rate-limiting enzyme in the mevalonate pathway, is essential for the biosynthesis of shikonin in Lithospermum erythrorhizon. However, in the absence of sufficient data, the principles of a genome-wide in-depth evolutionary exploration of HMGR family members in plants, as well as key members related to shikonin biosynthesis, remain unidentified. In this study, 124 HMGRs were identified and characterized from 36 representative plants, including L. erythrorhizon. Vascular plants were found to have more HMGR family genes than nonvascular plants. The phylogenetic tree revealed that during lineage and species diversification, the HMGRs evolved independently and intronless LerHMGRs emerged from multi-intron HMGR in land plants. Among them, Pinus tabuliformis and L. erythrorhizon had the most HMGR gene duplications, with 11 LerHMGRs most likely expanded through WGD/segmental and tandem duplications. In seedling roots and M9 cultured cells/hairy roots, where shikonin biosynthesis occurs, LerHMGR1 and LerHMGR2 were expressed significantly more than other genes. The enzymatic activities of LerHMGR1 and LerHMGR2 further supported their roles in catalyzing the conversion of HMG-CoA to mevalonate. Our findings provide insight into the molecular evolutionary properties and function of the HMGR family in plants and a basis for the genetic improvement of efficiently produced secondary metabolites in L. erythrorhizon. [ABSTRACT FROM AUTHOR]

Methyl orange (MO) is mutagenic, poisonous, and carcinogenic in nature, hence, effective methods are required for its degradation. We have synthesized pure ZrO2, Ag-doped ZrO2, and Ag-doped ZrO2/rGO as hybrid photocatalysts by facile hydrothermal method. These photocatalysts were characterized by powder XRD, scanning electron microscopy, EDX, FTIR, photoluminescence, UV–Vis diffuse reflectance (DRS), and Raman spectroscopy. The photodegradation of MO (10 ppm) was studied with pure ZrO2, Ag-doped ZrO2, and Ag-doped ZrO2/rGO (10 mg/100 mL catalyst dosage) photocatalysts at 100 min irradiation time under UV–Visible light. The pH effect and catalyst dosage on photodegradation of MO was investigated. Ag0.04ZrO2/rGO photocatalyst exhibited the maximum photocatalytic degradation of MO (87%) as compared to Ag0.04ZrO2 (60%) and pure ZrO2 (26%). Reusability experiments ensured the excellent stability of photocatalyst after five consecutive experiments. To the best of our knowledge, this is the first report on the facile hydrothermal synthesis of Ag0.04ZrO2/rGO photocatalyst for photocatalytic degradation of methyl orange. [ABSTRACT FROM AUTHOR]

Environment friendly and cost-effective structure-directing agents (SDAs) are highly desirable for the development of purposely designed functional nanomaterials. To comply, we aimed to explore vegetable waste extracts as potential SDAs for the synthesis of ZnO–CuO nanocomposites. Extracts of wastes of three different vegetables (cauliflowers, potatoes, and peas) were used, and their impact upon crystal structure, morphology, optical-band-gap (Eg), and photocatalytic efficiency of ZnO–CuO was explored. XRD and SEM revealed that the crystallite size and morphology varied with the vegetable waste extract. Similarly, the wide Eg of n-type ZnO narrowed upon coupling with p-type CuO, and also varied significantly with the vegetable waste extract. The resulting ZnO–CuO nanocomposites were used as photocatalysts for the degradation of model environmental pollutant (an organic dye) under visible light, and it was found that 95.6%, 93%, and 91.3% of the dye decomposes in 120 min under ZnO–CuO photocatalysts synthesized using cauliflower, peas, and potatoes waste extracts, respectively. [ABSTRACT FROM AUTHOR]

Toxicity of heavy metals to higher life forms is ascribed to mobility and accumulation in water reservoir. Adsorption offers a promising alternative to treat wastewater. This article proposes green and economically viable options for the replacement of expensive commercial adsorbent. The spentCamelia sinensis(black tea) andGallus domesticus(hen egg shell) powder under identical experimental conditions possesses better sorbing potential for cadmium (Cd) and lead (Pb). The adsorbents can be conveniently regenerated with HCl solution. The proposed adsorbents were found successful in situ remediation of textile, pharmaceutical, and leather industry effluents. Cost benefit and batch sorption analysis strongly recommends the present experimental endeavor for commercial scale up. [ABSTRACT FROM PUBLISHER]