Occurrence and removal of estrogenic short-chain ethoxy nonylphenolic compounds and their halogenated derivatives during drinking water production

The elimination of nonylphenol (NP), nonylphenol mono- and diethoxylates (NP1EO and NP2EO), nonylphenol carboxylates (NP1EC and NP2EC) and their brominated and chlorinated derivatives during drinking water treatment process in Sant Joan Despf waterworks in Barcelona was investigated utilizing a recently developed, highly sensitive LC-MS-MS method. The concentration of these potentially estrogenic compounds in raw water entering waterworks (taken from the Llobregat River, NE Spain) ranged from 8.3 to 22 microg/L, with NP2EC being the most abundant compound. Prechlorination reduced the concentration of short-chain ethoxy NPECs and NPEOs by about 25-35% and of NP by almost 90%. However, this reduction of concentrations was partially due to their transformation to halogenated derivatives. After prechlorination, halogenated nonylphenolic compounds represented approximately 13% of the total metabolite pool, of which 97% were in the form of brominated acidic metabolites. The efficiency of further treatment steps to eliminate nonylphenolic compounds (calculated for the sum of all short-chain ethoxy metabolites including halogenated derivatives) was as follows: settling and flocculation followed by rapid sand filtration (7%), ozonation (87%), GAC filtration (73%), and final disinfection with chlorine (43%), resulting in overall elimination ranging from 96 to 99% (mean 98% for four sampling dates). A few of the nonylphenolic compounds (NP, NP1EC, and NP2EC) were also identified in drinking water; however, the residues detected were generally below 100 ng/L, with one exception for NP2EC in November 2001 when a concentration of 215 ng/L was detected.     

Genetic and chemical assessment of Arbequina olive cultivar grown in Córdoba province,Argentina

BACKGROUND: Thirty‐eight accessions of olive (Olea europaea L.) originating from Córdoba province (Argentina) and preliminarily identified as belonging to the Arbequina variety were genotyped using AFLP (amplified fragment length polymorphism) DNA markers. Also, the oil chemical composition was studied during three consecutive crop years. The objectives of the work were (a) to investigate genetic intra‐cultivar diversity and (b) to evaluate the oil chemical composition and compare it with that of Arbequina oil produced in Spain. RESULTS: The 19 primer combinations employed to perform the AFLP analysis produced 98 polymorphic bands. A reduced genetic heterogeneity was obtained, confirming that (a) the selected accessions belong to the Arbequina variety and (b) the traditional vegetative propagation practice has caused low genetic erosion in this variety cultivated in Córdoba. The main features that characterise the Argentinian Arbequina oils studied are the lower content of oleic acid and higher levels of phenolics and high‐molecular‐weight volatile compounds compared with those found in Spanish Arbequina oils. CONCLUSION: In spite of the small proportion of intra‐cultivar variability, the Arbequina variety grown in Argentina produces oils with different chemical traits from those obtained in the original Spanish growing region. These differences can be attributed mainly to the particular environmental conditions of the olive‐growing areas in these countries. Copyright © 2008 Society of Chemical Industry     

Mode II interlaminar fracture behavior of carbon bead‐filled epoxy/glass fiber hybrid composite

To investigate the effect of including carbon beads on the mechanical properties of epoxy resin, the fracture toughness of carbon bead‐filled epoxy was earlier evaluated using a CT (compact tension) specimens and Mode I fracture toughness was observed. Based on those results, in this study, the Mode II interlaminar fracture toughness of carbon bead filled epoxy/glass fiber hybrid composites was evaluated using end notch flexure (ENF) specimens. The hybrid composites showed increased Mode II interlaminar fracture toughness. The optimal bead volume fraction was around 15%.     

Characterization and DC electrical conductivity of the composite films containing polyaniline‐carboxymethyl cellulose

New polymer composites containing polyaniline‐carboxymethyl cellulose (PANI‐CMC) were prepared via the polymerization of aniline hydrochloride using different concentration (wt%) of sodium CMC using ammonium persulfate as an oxidant. The thermal stability and embedded crystallinity of the composites were investigated using thermogravimetric and X‐ray diffraction analysis method, respectively. The electrical properties of the composites were examined using temperature‐dependent DC conductivity within 300–500 K. As compared to pure polyaniline the composites with increasing CMC in the PANI‐CMC composites shows the enhancement in the higher crystallinity and thermal stability, and higher electrical conductivities under equivalent conditions. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers