Evolution of soluble carbohydrates during the development of pea, faba bean and lupin seeds

Seeds of pea (Pisum sativum L. cv. Ergo), faba bean (Vicia faba ssp. minor Harz., cv. Tibo) and yellow pea lupin (Lupinus luteus L. cv. Juno) were sampled at different days after flowering (DAF) and their content of soluble carbohydrates was determined: Analysis of samples showed thatmyo-inositol, fructose, glucose, galactose and sucrose were found in high abundance early in development and their content decreased gradually during maturation. -Galactosides, which includes the content of raffinose, stachyose and verbascose, started to appear later in seed development, at 37 DAF in peas, 40 DAF in faba beans and 45 DAF in lupins. Their accumulation increased considerably during seed growth, and the maximum content was obtained in mature seeds; 3.8% in peas, 4.5% in faba beans and 10.4% in lupins. Results obtained for these sugars during seed development were fitted to modelling curves in order to predict sugar content at different development stages.     

Towards continuous sustainable processes for enzymatic synthesis of biodiesel in hydrophobic ionic liquids/supercritical carbon dioxide biphasic systems

The excellent suitability of immobilized Candida antarctica lipase B (Novozym 435) catalyst to carry out the synthesis of methyl oleate (biodiesel) by methanolysis of triolein in ILs based on imidazolium cations with large alkyl side chain (from C₁₂ to C₁₈) has been demonstrated at 60 and 85 °C. The phase behaviour of IL/triolein/methanol and IL/methyl oleate mixtures were studied at different concentrations and temperatures, the best results (up to 98.6% biodiesel yield after 6 h) being obtained for ILs able to provide monophasic reaction systems, i.e. 1-methyl-3-octadecylimidazolium bis(trifluoromethylsulfonyl)imide). A continuous enzymatic reactor, based on biocatalysts particles coated with hydrophobic ILs, for biodiesel synthesis in supercritical carbon dioxide was studied at 60 °C and 180 bar. The operational stability of the immobilized lipase was improved by its coating with ILs, i.e. 1-methyl-3-octadecylimidazolium hexafluorophosphate, leading to a two-phase systems with respect to the biodiesel product, which showed an excellent catalytic behaviour in continuous operation under supercritical conditions (up to 82% biodiesel yield after 12 cycles of 4 h).     

Factors Affecting the Ambient Physicochemical Properties of Cerium-Containing Particles Generated by Nanoparticle Diesel Fuel Additive Use

Despite the use of cerium oxide nanoparticles (nCe) in some regions as a diesel fuel additive, the physicochemical properties of the resulting exhaust particles in the ambient atmosphere are not well known. The mixing state of ceria with other exhaust particles is one such physicochemical property that has been shown to potentially affect ecosystem/human health. In this study, cerium-containing particles associated with an nCe additive were collected in the laboratory and in Newcastle-upon-Tyne, UK where the local bus fleet uses the Envirox nCe additive. Electron microscopy of laboratory-generated exhaust samples indicated both individual ceria and soot particles (external mixture) and ceria contained within soot agglomerations (internal mixture). Low ambient concentrations prevented quantification of the ceria particle mixing state in the atmosphere; therefore, a multicomponent sectional aerosol dynamic model was used to predict the size, chemical composition, and mixing state of ceria particles as a function of distance from an idealized roadway. Model simulations predicted that most ceria particles remain nonmixed in the ambient atmosphere (300 m downwind from the roadway) due to slow coagulation, with the mixing rate most sensitive to the ceria content of emitted nuclei-mode particles and the particle concentration upwind of the road. Although microscopy analysis showed both external and internal mixtures of ceria and soot in freshly emitted particles, the ambient mass concentration, and size distribution of ceria particles predicted by the model was insensitive to the emitted mixing state.

Copyright 2015 American Association for Aerosol Research     

Probability of Pressure Deficit in On-Demand Branched Networks and Incorporation into Design Decisions

This technical paper presents analytical expressions to estimate the probability function of head losses in any path of an on-demand branched irrigation network. They are developed for estimating the probability of pressure deficit of a given magnitude at any hydrant. They are also useful for examining the probability of a power deficit at a pumping station designed to guarantee service to a hydrant, as well as the head characteristic curve of the distribution system linked to a definite probability. All this quantified information is useful for decision making on network design and performance. The probabilities calculated with the developed expressions can be taken as complementary or alternative concepts to Clément’s classical design flow method, which is taken here as a benchmark for comparisons. Illustrative examples of network designs are presented to validate the proposed expressions. The least cost design solutions using Clément’s design flows are compared with design solutions here obtained to get the same probability of pressure deficit at the most unfavorable hydrants. The new solutions are less expensive because the flow constraint can be avoided.     

Synthesis of a porphyrin–C60 dyad for potential use in solar energy conversion

A convenient procedure for the synthesis of a new porphyrin–C₆₀ dyad via the reaction between 5-(4-aminophenyl)-10,15,20-tris(4-methoxyphenyl) porphyrin and a C₆₀ carboxylic acid is described. The results of preliminary photoelectrochemical studies on nanostructured SnO₂ electrodes coated with the new dyad suggest that the resultant substrate is suitable for solar energy conversion devices.     

An octaethylene glycol monododecyl ether-based mixed micellar assay for determining the lipid acyl hydrolase activity of patatin

Patatin was extracted from potato tubers (Solanum tuberosum L. cv. Spunta) and purified to homogeneity by ammonium sulfate salt fractionation and one sole chromatographic step. A spectrophotometric mixed micellar assay for patatin lipid acyl hydrolase (LAH) activity was designed with the detergent octaethylene glycol monododecyl ether (C₁₂E₈). Patatin LAH used p-nitrophenyl butyrate (PNP-butyrate) as substrate when solubilized in (C₁₂E₈) micelles. In the mixed micellar system, patatin LAH responds to the PNP-butyrate surface concentration expressed as mol% (=[PNP-butyrate]·100/([detergent]-critical micellar concentration)) and not to the molarity of PNP-butyrate. The kinetic parameters were determinined; V _max was independent of the mixed micelle concentration, as was K _m, when expressed as mol%. However, K _m was dependent on C₁₂E₈ concentration when expressed in molar concentration. C₁₂E₈/PNP-butyrate proved to be a reliable system for assaying patatin LAH activity and is superior to the commonly used Triton X-100 and SDS methods. It permits investigation of the substrate requirements of patatin LAH activity because the concentration-independent K _m can be determined both in mol% and as the absolute number of substrate molecules per micelle. In addition, the detergent did not affect the enzyme activity.     

Analytical Relationships for Designing Rectangular Drip Irrigation Units

Approximate analytical expressions were obtained that relate uniformity indices of water distribution in rectangular drip irrigation units as a function of the variables that define that unit: lengths and diameters of laterals and submain, spacing of emitters and laterals, ground slopes, parameters of the emitter discharge equation, and equivalent lengths characterizing local losses. The proposed expressions offer greater precision than might be needed in irrigation practice. They do not require iterative calculations and improve the procedures normally used. They may be useful in the design of drip irrigation units and in their evaluation and management. An example of their application is offered. The proposed relationships simplify studies of the sensitivity of variables involved in optimum hydraulic design. Users are thus allowed a rational understanding of their influence, improving that which can be gained from computer programs. Graphs obtained with the mentioned expressions are also offered. They can be of interest, although their use is not treated specifically in this paper.