Anomalous behavior of aminohydroxynaphthalenesulfonic acids during diazo coupling

The effect of pH on the diazo coupling reaction of some commonly used coupling components (J-acid, Gamma acid, H-acid and S-acid) with monosubstituted diazobenzenes has been investigated. The results demonstrate that, contrary to previous reports, selective diazo coupling ortho to an amino group of an aminohydroxynaphthalenesulfonic acid does not occur in weakly acidic (pH 5–6) media. In fact, such media were found to give nearly exclusive diazo coupling ortho or para to the hydroxyl group. The desired amine coupling reactions required a pH of 3.0–3.5 and occurred only with the more reactive diazonium salts. The structures of the dyes obtained were unambiguously determined with the aid of ¹H-NMR spectroscopy.     

Processing,Quality,Safety,and Acceptance of Meat Analogue Products

Rapid global population growth has caused an increasing need for products containing protein.Meat products are the most common high-protein food source,but impa...     

Solar desalination in conjunction with controlled environmental agriculture in Arid zones

There are many factors which favor the juxtaposition of a solar still to a controlled environment agriculture (CEA) greenhouse. A modular, easy on-site construction, low-cost solar still was designed and tested. Its annual average daily productivity and efficiency values were 2.35 l/m² and 30%, respectively. The feasibility of using the CEA greenhouse's hot brackish water reservoir as the still feedstock for enhanced nocturnal production was tested and found to enhance productivity significantly. A total lifecycle cost analysis of the solar still has shown it to be less economical by a factor of 1.25, relative to a small reverse osmosis unit for the CEA farm size considered, in the case of brackish water, whereas, in the case of sea water desalination, the solar still may be more economical.     

Enhanced bioactivity of Zanthoxylum schinifolium fermented extract: Anti-inflammatory,anti-bacterial,and anti-melanogenic activity

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Variation in fatty acid composition of ewes' colostrum and mature milk fat

Temporal content variations of approximately 70 C4–C24 fatty acids (FA) in colostrum and milk of ewes consuming winter diet were determined by gas chromatography. The content of monounsaturated, polyunsaturated and straight-chain saturated FA 14:0–16:0 in colostrum was higher whereas the content of 4:0–12:0, 18:0 and branched-chain saturated FA 15:0–17:0 was lower than that in mature milk. The effect of ewe breed on the FA profiles was not significant. The composition of FA changed most significantly 1–2 days after lambing in agreement with the time schedule of colostrum formation. Nevertheless, the content of FA further successively changed up to approximately the 6th day of lactation, whereas further changes up to the 60th day of lactation were smaller. This is consistent with the recommendation that ewes' milk is suitable for human consumption after six-to-eight days of lactation. The higher contents of palmitic and myristic acids in colostrum compared with mature milk suggest that FA composition in colostrum matches the changing needs of the growing lambs.     

An eco-friendly process: Predictive modelling of copper adsorption from aqueous solution on Spirulina platensis

The adsorption of copper ions on Spirulina platensis was studied as a function of contact time, initial metal ion concentration, and initial pH regimes. Characterization of this adsorbent was confirmed by FTIR spectrum. Modified Gompertz and Logistic models have not been previously applied for the adsorption of copper. Logistic was the best model to describe experimental kinetic data. This adsorption could be explained by the intra-particle diffusion, which was composed of more than one sorption processes. Langmuir, Freundlich, and Redlich–Peterson were fitted to equilibrium data models. According to values of error functions and correlation coefficient, the Langmuir and Redlich–Peterson models were more appropriate to describe the adsorption of copper ions on S. platensis. The monolayer maximum adsorption capacity of copper ions was determined as 67.93 mg g^?1. Results indicated that this adsorbent had a great potential for removing of copper as an eco-friendly process.     

CFD studies on natural convective heating of canned food in conical and cylindrical containers

Enhancing natural convective heat transfer in canned food sterilization is explored through modifications to container geometry and its orientation. A conical geometry, of equal volume and height as that of the cylinder, pointing either vertically up or down was considered. The non-Newtonian fluid, 0.85% w/w sodium carboxy-methyl cellulose (CMC), was taken as the test food material and its laminar flow behavior was investigated using computational fluid dynamics (CFD). The movement of the slowest heating zone (SHZ) temperature was tracked and compared for the three geometries. The SHZ temperature was observed to attain the final sterilization fluid temperature of 100 °C fastest for an upright conical geometry followed by the cylinder and the downward pointing cone. There is scope for enhancing the thermal sterilization process through geometry modifications but without mechanical agitation or rotation. Further, the geometry modification if non-uniform must be complemented by its suitable orientation.