Catalytic transesterification of corn oil and tristearin using immobilized lipases from Thermomyces lanuginosa

Thermomyces lanuginosa lipase was employed to catalyze the interesterification reaction between corn oil and tristearin at 45°C in a solvent-free system. HPLC and GC analyses were used to monitor both the distribution of TAG and the concentrations of MAG, DAG, and TAG as the reaction progressed. The positional distribution of the FA residues in the interesterified product was also determined for comparison to that of the original corn oil. Two different weight ratios of corn oil to tristearin were studied. Addition of molecular sieves to the reaction medium reduced the percentage of hydrolysis from 15 to 7. In order to improve the results obtained with Lipozyme TL IM, an immobilization of T. lanuginosa lipase was carried out. At a solids loading of 10% (w/w), the new immobilized lipase reduced the concentration of tristearin from 6 to 0.5% in only 30 min.     

Hybrid System for Robust Faces Detection

The automatic detection of faces is a very important problem. The effectiveness of biometric authentication based on face mainly depends on the method used to locate the face in the image. This paper presents a hybrid system for faces detection in unconstrained cases in which the illumination, pose, occlusion, and size of the face are uncontrolled. To do this, the new method of detection proposed in this paper is based primarily on a technique of automatic learning by using the decision of three neural networks, a technique of energy compaction by using the discrete cosine transform, and a technique of segmentation by the color of human skin. A whole of pictures （faces and no faces） are transformed to vectors of data which will be used for learning the neural networks to separate between the two classes. Discrete cosine transform is used to reduce the dimension of the vectors, to eliminate the redundancies of information, and to store only the useful information in a minimum number of coefficients while the segmentation is used to reduce the space of research in the image. The experimental results have shown that this hybridization of methods will give a very significant improvement of the rate of the recognition, quality of detection, and the time of execution.     

Viscoelastic,thermo-mechanical and environmental properties of composites based on polypropylene/poly(lactic acid) blend and copper modified nanoclay

Poly(lactic acid) (PLA)/polypropylene (PP) blends composites were prepared by incorporating 3 wt.% of copper modified montmorillonite (MMT-Cu²⁺), obtained using cation exchange in a CuSO₄ solution, and 10 wt.% of polypropylene-graft-maleic anhydride (PP-g-MA) as a compatibilizer then varying the PLA content until 50 wt.%. These materials were subjected to several investigations such as X-rays diffraction, dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and tensile and environmental tests. The DMTA analysis showed that the glassy PLA high stiffness and the PP crystalline phase compensate the decrease in the storage modulus occurring during the PP and PLA glass transitions, respectively. The variations of tan δ revealed no changes on the PP and PLA phases glass transitions temperatures which indicate the immiscibility of the two polymers, as supported by DSC analysis. Blends composites SEM micrographs stated the immiscibility of the system resulting in the poor adhesion of the PLA droplets to the PP matrix. Also, the blends composites exhibited intermediate tensile properties between those of PP and PLA. The incorporation of MMT-Cu²⁺ to the (50/50) PP/PLA blend accentuated its aptitude to water absorption and ensured an efficient antimicrobial activity over a satisfactorily long period of around six months.     

Trace element level in infant hair and diet, and in the local environment of the Moroccan city of Marrakech

A sample of 573 infants (aged 0 to 12 months) from the Moroccan city of Marrakech was studied in order to determine the level of Pb and Al contaminations. Mean values of Pb and Al in children's hair were 6.6 and 9.5 microg/l, respectively. Age, gender, and parents' occupation influenced significantly Pb content but not Al content. Larger mean values were measured for Al compared with Pb. This finding can be explained by a higher level of Al available in both the infant diet (complementary feeding) and the local environmental factors (soil and drinking water). During weaning, beverages like tea, widely used in Morocco, represent an important source of Pb and Al contamination. Al content in drinking water is above the international standard.     

Impulsive fractional differential equations with variable times

In this paper, we establish sufficient conditions for the existence of solutions for a class of initial value problem for impulsive fractional differential equations with variable times involving the Caputo fractional derivative.     

Housing and the Creation of Home for Refugees in Western Australia

Safe, appropriate housing is vital for the successful settlement of refugees, since establishing a home is part of the process of redeveloping a sense of ontological security. However humanitarian entrants in Australia have a far greater likelihood of moving multiple times in the early years of settlement and are far less likely to be purchasing their homes compared to other migrants. Using data from interviews, focus groups and a photovoice exercise, positive home-building experiences of refugees are illustrated, while factors leading to negative outcomes are also identified. The more positive story came from the photovoice exercise with images of the remaking of home as a place of connection with others, of personal pride, of comfort and leisure, of family and commensality. Interview and focus group data focused on structural issues including the cost of housing, limited choice in the rental market, lack of public housing, poor quality, negative attitudes of real estate agents, lack of access to services, and complex tenancy procedures which are key factors influencing insecurity of tenure. The effects on refugees’ sense of ontological security are discsused.     

Extraction of naphthalene. Optimization and application to an industrial rejected fuel oil

The extraction efficiency of naphthalene from an organic phase depends essentially on the choice of extractant. It can be enhanced through the optimization of operating parameters. The organic phase studied was a fuel oil rejected at the process end of the coke gas treatment in an industrial plant of Annaba (Algeria). The mixture of methanol–phenol has been selected as extractant for its best efficiency. The amount of naphthalene in the oil phase was analyzed by refractometry and verified by infrared spectroscopy. The temperature, the density of methanol–phenol mixture and the quantity of extractant, were considered as the main parameters which affect the performance of extraction. Response surface methodology was applied to investigate the yield of extraction. A Box-Behnken design was used to produce models for objective responses based on parameters that have significant probabilities. It was developed by using these three main parameters at three levels. Analysis of variance showed that temperature and the volume ratio are the most affecting parameters on extraction yield. The developed regression equations described interdependencies between the input parameters and yield of extraction as responses. The results that were treated statistically were very interesting and allowed to deduce the optimum conditions for the best extraction efficiency which was in order to 80.38%. The application of extraction in these conditions has permitted to regenerate the fuel oil rejected by the industrial unit for other uses. The phenol–methanol mixture containing naphthalene can also be regenerated (91.8% of methanol and 94.2% of phenol) and more than 1 ton of pure naphthalene per day can be recovered. This could be very important for the industrial unit on decreasing the cost of the fuel consumption and more profits by producing pure naphthalene.     

Augmented reality HUD vs. conventional HUD to perform a navigation task in a complex driving situation

Cognition, Technology & Work - This study aims at investigating the added value of an augmented reality head-up display (AR-HUD) in relation to a conventional head-up display (C-HUD) to perform...     

Factors influencing the ignition of flames from air-fired swirl pf burners retrofitted to oxy-fuel

Combustion tests were undertaken in a vertical pilot-scale furnace (1.2 MWt) at the IHI test facility in Aioi, Japan, to compare the performance of an air fired swirl burner retrofitted to oxy fired pf coal combustion with the oxy fired feed conditions established to match the furnace heat transfer for the air fired case. A turn down test at a reduced load was also conducted to study the impact on flame stability and furnace performance.Experimental results include gas temperature measurements using pyrometry to infer the ignition location of the flames, flue gas composition analysis, and residence time and carbon burnout. Theoretical computational fluid dynamics (CFD) modelling studies using the Fluent 6.2 code were made to infer mechanisms for flame ignition changes.Previous research has identified that differences in the gas compositions of air and oxy systems increase particle ignition times and reduce flame propagation velocity in laminar systems. The current study also suggests changes in jet aerodynamics, due to burner primary and secondary velocity differences (and hence the momentum flux ratio of the flows) also influence flame shape and type.For the oxy fuel retrofit considered, the higher momentum flux of the primary stream of the oxy-fuel burner causes the predicted ignition to be delayed and occur further distant from the burner nozzle, with the difference being accentuated at low load. However, the study was limited to experimental flames being all Type-0 (low swirl with no internal recirculation), and therefore future work consider higher swirl flames (with internal recirculation) more common in industry.