Eco-efficiency and techno-economic analysis for maleic anhydride manufacturing processes

Clean Technologies and Environmental Policy - Maleic anhydride may be obtained from different technological routes, being the selective oxidation of benzene and oxidation of butane the only ones...     

Fracture toughness of high strength seamless pipe steel from SE(T) and SE(B) specimens evaluated by different standards

Recently released, BS 8571:2014 standard offers an alternative for the experimental determination of fracture toughness and resistance curves of metallic materials from SE(T) specimens. Similar in stress conditions and constraint to cracked tubes, specimens in SE(T) geometry should yield less conservative toughness values than conventional high‐constraint specimens, such as SE(B) geometry. However, the convention to determine the J‐integral fracture toughness proposed in the new BS standard is different from ASTM standards. In this work, SE(T) and SE(B) specimens of similar dimensions of a tough high‐strength seamless pipe steel were tested following the BS 8571:2014 and ASTM E1820‐16 standards, respectively. Because of the different standardized definitions, SE(T) specimens yield lower fracture toughness than SE(B) specimens, which could lead to more conservative results in structural integrity analysis. This investigation also suggests the introduction of the blunting line concept in the BS 8571:2014 standard in order to minimize this problem.     

Grape,apple and pineapple juice characterisation and detection of mixtures

Several multivariate statistical methods (principal component, cluster, stepwise discriminant and multiple linear regression analysis) were applied to analytical data obtained by conventional methods and to analytical data for free amino acids, in an attempt to distinguish between grape, apple and pineapple juice. Analysis for methionine, proline, asparagine, arginine and glutamic acid made it possible to differentiate among the 34 samples of grape, apple and pineapple juices studied. Multiple linear regression analysis of computer-simulated mixtures of grape and apple juices made it possible to detect the proportion of each fruit within the blend.     

A comprehensive study of hazelnut oil composition with comparisons to other vegetable oils,particularly olive oil.

Crude and refined hazelnut oils from different countries were characterised by major and minor compounds. Fatty acids, triacylglycerides, waxes, sterols, methyl-sterols, terpenic and aliphatic alcohols, tocopherols, tocotrienols and hydrocarbons were identified and quantified by gas chromatography and high-performance liquid chromatography. The levels of these chemical compounds in hazelnut oils together with the equivalent carbon numbers and triacylglyceride carbon numbers, were compared with the results of analyses of samples of other vegetable oils. The statistical procedure of cluster analysis was used to characterise hazelnut oils versus other edible oils.     

Isolation and characterization of predominant microorganisms during decomposition of waste materials in a field-scale composter

A self-heating field-scale composter treating agro-industrial wastes within a period of 30 d was analyzed by denaturing gradient gel electrophoresis (DGGE) (Pedro et al., J. Biosci. Bioeng., 91, 159-165, 2001). Three major bands were derived from Propionibacterium acnes, Methylobacterium mesophilicum or M. radiotolerans, and Bacillus thermocloacae. Strains MSP09A and MSP06G with close affiliation to P. acnes and B. thermocloacae, respectively, were successfully isolated. Based on quantitative-PCR results, the relative population of MSP09A increased towards the end of the composting process (mesophilic stage) while MSP06G seemed to predominate during the middle period (thermophilic stage). These results correlated highly with their growth temperatures. MSP09A and MSP06G had different metabolic profiles which were largely affected by culture conditions. MSP09A was able to utilize large complex molecules of lipids and proteins. An interspecies relationship in terms of metabolites such as propionic acid was expected between the two microorganisms.     

Evolution of available lysine and furosine contents in milk‐based infant formulas throughout the shelf‐life storage period

The evolution of the Maillard reaction (MR) by measuring the available lysine and furosine (FUR) contents in adapted and follow‐up powdered milk‐based infant formulas over the shelf‐life storage period, at 20 and 37 °C, was studied. Available lysine and FUR contents were determined by fluorimetry and high‐performance liquid chromatography respectively. Statistically significant differences were found between adapted and follow‐up infant formulas with respect to the available lysine and FUR contents. Available lysine contents decreased significantly throughout the storage time, and the contents at 37 °C were lower than at 20 °C. A statistically significant increase in FUR contents was observed during the storage period, with the contents being high at 37 °C than at 20 °C. A simple regression analysis between the available lysine and FUR contents during (a) the first year (b) the second year and (c) the two storage years was applied. The best correlations were obtained during the first year of storage. The results obtained show a clear MR evolution during the storage of infant formulas. Copyright © 2003 Society of Chemical Industry