Treatment of paper and pulp wastewater and removal of odorous compounds by a Fenton‐like process at the pilot scale

A Fenton‐like process, involving oxidation and coagulation, was evaluated for the removal of odorous compounds and treatment of a pulp and paper wastewater. The main parameters that govern the complex reactive system [pH and Fe(III) and hydrogen peroxide concentrations] were studied. Concentrations of Fe(III) between 100 and 1000 mg L^?1 and of H₂O₂ between 0 and 2000 mg L^?1 were chosen. The main mechanism for color removal was coagulation. The maximum COD, color and aromatic compound removals were 75, 98 and 95%, respectively, under optimal operating conditions ([Fe(III)] = 400 mg L^?1; [H₂O₂] = 500–1000 mg L^?1; pH = 2.5; followed by coagulation at pH 5.0). The biodegradability of the wastewater treated increased from 0.4 to 0.7 under optimal conditions and no residual hydrogen peroxide was found after treatment. However, partially or non‐oxidized compounds present in the treated wastewater presented higher acute toxicity to Artemia salina than the untreated wastewater. Based on the optimum conditions, pilot‐scale experiments were conducted and revealed a high efficiency in relation to the mineralization of organic compounds. Terpenes [(1S)‐α‐pinene, β‐pinene, (1R)‐α‐pinene and limonene] were identified in the wastewater and were completely eliminated by the Fenton‐like treatment. Copyright © 2006 Society of Chemical Industry     

Modeling the adversary and success in competition.

Competition has been studied as something to be averted, yet rarely has it been asked what processes may be involved in successful competition. The authors tested whether more accurate modeling of an adversary can assist competitive success. Pairs played a zero-sum game with no specific skill component over 40 trials. The authors measured the relative accuracy of the players' second-order model (i.e., what I think about my opponent: R2MA) and third-order model (i.e., what I think my opponent thinks of me: R3MA), using responses to adjectives indicating personality traits. Performance correlated with both R3MA and having a better strategy (i.e., a better distribution of responses), but these variables contributed separately to performance variance. However, R2MA did not correlate with performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Continuous Fabrication of Silicon Carbide Fiber Tows by Chemical Vapor Deposition

The feasibility of preparing small-diameter, high-strength, thermally stable silicon carbide fiber tows by the continuous chemical vapor deposition (CVD) of SiC onto carbon fiber tows was experimentally evaluated. Calculations of bending stresses and stresses caused by thermal expansion mismatch between the substrate and coating were used to evaluate the influence of coating thickness and substrate fiber diameter and type. Statistically designed and analyzed processing studies quantitatively showed the influence of key CVD process variables (temperature, pressure, and flow rates of CH₃SiCl₃ and H₂) on fiber attributes such as coating thickness and uniformity, surface roughness, percent agglomeration, and strength. Emphasis was given to conceiving and evaluating various fiber spreading devices in order to enhance coating uniformity and to minimize filament agglomeration within a tow. Uniform coatings and fiber tensile strengths as high as 4 GPa were achieved.     

Detection of GMO in food products in Brazil: the INCQS experience

Regulations for the use and labeling of genetically modified organism products and derived ingredients are being implemented worldwide, what demands reliable and accurate methods to detect genetically modified organisms (GMO) in raw materials and food products. This study aimed at monitoring products derived from GMO in the Brazilian market using detection methods for the presence of Roundup Ready soybean, Bt176 and MON 810 maize. The results demonstrate for the first time the presence of GM-soy in Brazilian food products, reinforcing the need for the development of accurate quantitative methods in routine analyses.     

Relationship of cocaine-induced c-Fos expression to behaviors and the role of serotonin 5-HT2A receptors in cocaine-induced c-Fos expression.

Serotonin 5-HT2A receptor antagonists have been shown to attenuate the locomotor stimulant effects of cocaine in rats. The present study used the expression of c-Fos protein as a marker to identify brain areas through which 5-HT2A receptors may modulate cocaine-induced behaviors. Significant correlations were observed between cocaine-induced hyperactivity and c-Fos expression in the nucleus accumbens core (NAcC), caudate-putamen (CPu), and subthalamic nucleus. In a separate experiment, a low, behaviorally relevant dose of cocaine was found to increase c-Fos immunoreactivity in the medial CPu, NAcC, and nucleus accumbens shell (NAcSh). The selective 5-HT2A receptor antagonist M100907 significantly attenuated cocaine-induced c-Fos expression in the medial CPu and in the NAcSh. These data suggest that 5-HT2A receptors in the NAcSh and CPu or in afferents to these regions may contribute to genomic responses to cocaine in the brain as well as to cocaine-induced locomotor activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Monitoring multivariate aviation safety data by data depth: control charts and threshold systems

Aviation safety analysis is increasingly needed in regulating air traffic and safety, in light of the rapid growth in air traffic density. With the recent advances in computer technology, large amounts of multivariate aviation safety data are now routinely collected in databases. Many existing analysis methods prescribed in those databases and corresponding safety indictors are based on classical statistical analysis, and their applicability are considerably restricted by the requirement of normality. An alternative nonparametric methodology based on data depth is pursued in this paper. For a given multivariate sample, a data depth can be used to measure their depth or outlyingness with respect to the underlying distribution. The measure of depth leads to a center-outward ordering of the sample points. Derived from this ordering, Liu (1995) introduced a simple, yet effective, control chart for monitoring multivariate observations. The control chart is combined here with properly chosen false alarm rates to develop meaningful threshold systems for multivariate aviation safety data for both regulating and monitoring purposes. The developed procedure is applied to the aviation inspection results collected by the Federal Aviation Administration (FAA) inspection system. The threshold system serves as a standard for evaluating the performance of aircraft operators, and provides clear guidelines for identifying unexpected performances and for assigning appropriate corrective actions.     

Online communication, compulsive internet use, and psychosocial well-being among adolescents: A longitudinal study.

The present study investigated the relationships between adolescents' online communication and compulsive Internet use, depression, and loneliness. The study had a 2-wave longitudinal design with an interval of 6 months. The sample consisted of 663 students, 318 male and 345 female, ages 12 to 15 years. Questionnaires were administered in a classroom setting. The results showed that instant messenger use and chatting in chat rooms were positively related to compulsive Internet use 6 months later. Moreover, in agreement with the well-known HomeNet study (R. Kraut et al., 1998), instant messenger use was positively associated with depression 6 months later. Finally, loneliness was negatively related to instant messenger use 6 months later. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Synthesis, Characterization, and Processing of Cordierite-Glass Particles Modified by Coating with an Alumina Precursor

The surfaces of cordierite and glass particles were modified by coating them with an alumina precursor using a precipitation process in the presence of urea. Scanning electron microscopy (SEM), high-resolution transmission electron microscopy, X-ray diffraction, electrophoresis, and rheological measurements were used to characterize the coated powders. SEM and transmission electron microscopy morphologies of the coated powders revealed that amorphous and homogeneous coatings have been formed around the particles. The morphology of the coated powders showed a coiled wormlike surface. The coating Al₂O₃ layer dominated the surface properties of the coated glass and cordierite powders. The influence of the coating layer on the processing ability of cordierite-based glass-ceramics substrates by tape casting was studied in aqueous media. It could be concluded that the coating of the powders facilitates the processing and yields green and sintered tapes with denser, more homogeneous microstructures compared with the uncoated powders.     

Trapping of soursop (Annona muricata) juice volatiles on porapak Q by suction

The trapping technique of Singleton and Pattee, in which the volatiles are swept to a Porapak Q trap by suction rather than by a sweeping gas, was modified and used to isolate soursop juice volatiles. Using fixed, low vacuum and operating conditions determined specifically for soursop volatiles, very high reproducibility was obtained. The majority of the peaks had a coefficient of variation less than 0.10. The relative amounts of the volatile components obtained by direct headspace sampling was fairly well maintained in the Porapak Q concentrate. The chromatograms showed distinct differences between two commercial brands or between lots of the same brand of soursop juice. The trapping technique appear to have wide applicability provided that the operating conditions are adapted to each product studied.