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Proteomic analysis and interactions network in leaves of mycorrhizal and nonmycorrhizal sorghum plants under water deficit
Get PDFFor understanding the water deficit stress mechanism in sorghum, we conducted a physiological and proteomic analysis in the leaves of Sorghum bicolor L. Moench (a drought tolerant crop model) of non-colonized and colonized plants with a consortium of arbuscular mycorrhizal fungi. Physiological results indicate that mycorrhizal fungi association enhances growth and photosynthesis in plants, under normal and wáter deficit conditions. 2D-electrophoresis profiles revealed 51 differentially accumulated proteins in response to water deficit, of which HPLC/MS successfully identified 49. Bioinformatics analysis of protein protein interactions revealed the participation of different metabolic pathways in nonmycorrhizal compared to mycorrhizal sorghum plants under water deficit. In noninoculated plants, the altered proteins are related to protein synthesis and folding (50S ribosomal protein L1, 30S ribosomal protein S10, Nascent polypeptide-associated complex subunit alpha), coupled with multiple signal transduction pathways, guanine nucleotide-binding beta subunit (Rack1) and peptidylprolyl- cis-trans isomerase (ROC4). In contrast, in mycorrhizal plants, proteins related to energy metabolism (ATP synthase-24kDa, ATP synthase), carbon metabolism (malate dehydrogenase, triosephosphate isomerase, sucrose-phosphatase), oxidative phosphorylation (mitochondrial-processing peptidase) and sulfur metabolism (thiosulfate/3-mercaptopyruvate sulfurtransferase) were found. Our results provide a set of proteins of different metabolic pathways involved in water deficit produced by sorghum plants alone or associated with a consortium of arbuscular mycorrhizal fungi isolated from the tropical rain forest Los Tuxtlas Veracruz, México
Analysis of intensified sustainable schemes for biobutanol purification
Get PDFButanol is an alternative fuel with characteristics competitive to petroleum-based fuels. Compared with ethanol, butanol shows less miscibility, flammability, and corrosion; while potentially replacing gasoline in car engines without modifications. However, the production cost of butanol from renewables feedstock, i.e. bio-butanol (which also contains acetone and ethanol) through fermentation remains high. This is mainly due to the low yield of butanol in fermentation. The conventional recovery of butanol by distillation is an energy-intensive
operation that has greatly restricted the industrial production of bio-butanol. This work studies ten hybrid and intensified configurations, based on the liquid-liquid extraction and dividing wall columns, to purify the butanol to the fuel grade. The study analyzes sustainability based on green metrics, including the inherent safety and control properties using singular value decomposition analysis. The results indicate that as long as the process is highly intensified, the sustainability and the inherent safety are improved and not necessarily the control properties. This is primarily due to the loss in the degrees of freedom in intensified processes
Uso de CLAR en fase inversa para la determinación del contenido de formaldehído libre en esmaltes de uñas
Get PDFSe determinó el contenido de formaldehído libre en 50 muestras de esmaltes para uñas de diversas marcas comercializadas en León, Guanajuato, México. El tratamiento de muestras se realizó de acuerdo con el método iso 17226-1:2003, con ligeras modificaciones: se pesaron 2±0,1 g de esmaltes en matraces Erlenmeyer de 100 ml, se adicionaron 40 ml de dodecil sulfonato de sodio al 0,1 %. Las muestras fueron entonces tapadas y se dejaron en baño María a 40 °c con agitación constante durante 60 minutos; posteriormente se filtraron y se tomaron alícuotas de cada muestra para su derivatización con 2,4-dinitrofenilhidracina al 0,3 % durante 60 minutos. La determinación analítica se realizó por CLAR en fase inversa con detección por arreglo de diodos. Resultados: se obtuvo como resultado que todas las muestras de esmaltes para uñas analizadas estuvieron por debajo del límite normativo de contenido de formaldehído libre en cosméticos de 0,2 %. Conclusiones: se obtuvo información de relevancia toxicológica sobre el formaldehído libre en los esmaltes de uñas, además de comprobar la versatilidad y robustez del método de prueba
Improving Mechanical Properties and Reaction to Fire of EVA/LLDPE Blends for Cable Applications with Melamine Triazine and Bentonite Clay
Get PDFThe high flame-retardant loading required for ethylene-vinyl acetate copolymer blends with polyethylene (EVA-PE) employed for insulation and sheathing of electric cables represents a significant limitation in processability and final mechanical properties. In this work, melamine triazine (TRZ) and modified bentonite clay have been investigated in combination with aluminum trihydroxide (ATH) for the production of EVA-PE composites with excellent fire safety and improved mechanical properties. Optimized formulations with only 120 parts per hundred resin (phr) of ATH can achieve self-extinguishing behavior according to the UL94 classification (V0 rating), as well as reduced combustion kinetics and smoke production. Mechanical property evaluation shows reduced sti_ness and improved elongation at break with respect to commonly employed EVA-PE/ATH composites. The reduction in filler content also provides improved processability and cost reductions.
The results presented here allow for a viable and halogen-free strategy for the preparation of highperforming EVA-PE composites
The influence of Al2O3 content on Al2O3-ZrO2 composite-textural structural and morphological studies
Get PDFIn this work binary Al2O3-ZrO2 composites with 25, 50, and 75%,w/wAl2O3 were synthesized by the sol-gel method, to find out the better Al2O3 amount that improve the texture, structure, and morphology. The composites presented high surface area, porosity and microcrystalline structure due to high cations dispersion induced by a good intermingling of the components.Wefound that structure of Al2O3-ZrO2 composites include AlO4 (tetrahedral), AlO5 (pentahedral) AlO6 (octahedral) polyhedral units. An increment of AlO4 and AlO6 species for low Al2O3 amount in the composites was observed. This was possibly related with segregated particles caused by progressive removal of hydroxyl groups. Otherwise, for high Al2O3 amount the fraction of AlO5 species was high, this behaviour was associated with an appropriate distribution of cations within the network of the composites as derived from condensation reactions. Asuitable distribution of the Al3+ and Zr4+ cations in the network of the composites is observable by Z-contrast where for high Al2O3 concentrations an homogeneous arrangement was observed. Besides, for low Al2O3 concentrations rods of ZrO2 with an average length at∼250nmare observable. Finally, by XPS analysis the non-lattice and lattice oxygen ratio presented similar values for Al50Zr50 composite, associated with the same available vacancies where Al3+ and Zr4+ cations have mayor mobility in the bulk and the superficial of the composite
Natural Keratin and Coconut Fibres from Industrial Wastes in Flame Retarded Thermoplastic Starch Biocomposites
Get PDFNatural keratin fibres derived from Mexican tannery waste and coconut fibres from coconut processing waste were used as fillers in commercially available, biodegradable thermoplastic starch-polyester blend to obtain sustainable biocomposites. The morphology, rheological and mechanical properties as well as pyrolysis, flammability and forced flaming combustion behaviour of those biocomposites were investigated. In order to open up new application areas for these kinds of biocomposites, ammonium polyphosphate (APP) was added as a flame retardant. Extensive flammability and cone calorimeter studies revealed a good flame retardance effect with natural fibres alone and improved effectiveness with the addition of APP. In fact, it was shown that replacing 20 of 30 wt. % of APP with keratin fibres achieved the same effectiveness. In the case of coconut fibres, a synergistic effect led to an even lower heat release rate and total heat evolved due to reinforced char residue. This was confirmed via scanning electron microscopy of the char structure. All in all, these results constitute a good approach towards sustainable and biodegradable fibre reinforced biocomposites with improved flame retardant propertie
Cross-flow filtration for the recovery of lipids from microalgae aqueous extracts: membrane selection and performances
Get PDFThe biore_nery of microalgae necessitates innovative choices of soft and energy-e_cient processes to guarantee the integrity of fragile molecules and develop eco-friendly production. A wet processing of biomass is proposed, which avoids expensive drying steps. It includes harvesting, cell dis- 5 ruption, and fractionation of the target compounds. Membrane _ltration is a promising clean fractionation step. In this paper, the recovery of lipids from starving Parachlorella kessleri aqueous extracts by cross-ow _ltration was studied. A model solution was formulated to test four membranes of di_erent materials (PVDF, PES, PAN) and cut-o_s (200 kDa - 1.5 μm). The 10 hydrophilic PAN 500 kDa membrane presented the best performance (ux stability, permeate ux, lipid retention, and cleanability) and was therfore selected for _ltrating real aqueous extracts. Similar permeation uxes were obtained with model and real products: 34 - 41 L h1 m2 respectively. The coalescence of lipid droplets was observed with model solutions but not 15 with real products, less concentrated. The lipids from the real products were wholly retained by the PAN membrane, whereas some of the polysaccharides and proteins were able to permeate. An optimization of the coupling between culture, cell disruption, clari_cation, and _ltration would allow a good concentration and puri_cation of the lipids from microalgae
Pollutant Removal from Wastewater at Different Stages of the Tanning Process by Electrocoagulation
Get PDFThe removal of chemical oxygen demand (COD), total organic carbon (TOC), turbidity, and chromium content from tannery wastewater at different stages of the process was experimentally investigated using electrocoagulation (EC) with iron and aluminium electrodes. In the EC of the beamhouse wastewater (S1), the effects of initial pH and current density were analyzed and electrical energy consumption was determined. 2e COD and TOC in the solution were effectively removed, with an initial pH 7.0, using either metallic electrode. With a current density of 28 mA/cm2 for an electrolysis procedure of 60 minutes, the removal efficiency of COD and TOC was 72% and 57% with aluminium electrodes and 69% and 60% with iron electrodes, respectively. 2e minimum energy consumption for the highest COD and TOC removal was 0.37 and 0.69 kWh/m3 when employing iron or aluminium electrodes, respectively. At the optimal conditions, removal efficiencies close to 100% for turbidity and chromium content for wastewaters S1-beamhouse, S2-tanning, S3-retanning, and S4-a mixture 1 :1 :1 (v/v/v) were achieved. Results show that a pseudosecond-order rate equation provides a good correlation for the removal rate of the parameters. Finally, the results indicate that for tannery wastewater, the EC process does not depend noticeably on the electrode material, but that the stage of the tanning process of wastewater sample has the principal effect on treatment efficiency
Curtido con extracto de acacia para valorar propiedades físicas del cuero para calzado
Get PDFEl presente proyecto surge por la propuesta de conocer las propiedades físicas y atributos propios que proporciona el extracto de acacia en el curtido así como las variables descritas (Tensión, elongación y ruptura de flor) para aplicaciones de empeine, se establecieron los objetivos con los que se manejó y se determinó por un diseño de experimentos para este proyecto, así como los resultados obtenidos en pruebas objetivas (pruebas físicas) y pruebas subjetivas (atributos del cuero para calzado) concluyendo con 2 pruebas positivas