Some health aspects of infections in oil and emulsions

A variety of potential health hazards associated with microbial infections of cutting oils have been postulated. This paper deals particularly with the inhalation of infected aerosols from such emulsions. An Andersen sampler detected up to 70000 viable bacteria/m³ of air 0.6m from a grinding machine in a machine shop, but this level decreased substantially further from the machine toolsPseudomonas aeruginosa, an accepted opportunistic pathogen, was present in the emulsions in the sumps and was detected in the air. However, when nasal swabs and sputum samples from 38 men were examined there was no indication that the respiratory tract had been colonised by Pseudomonas spp. It is suggested that the spoilage bacteria in the emulsions rapidly lose viability in an aerosol. The droplets however, are of a respirable size and dead bacteria may evoke respiratory response. Animal experiments indicated that infected emulsions exacerbate lung inflammation, serological responses and skin irritation     

Hybrid manufacturing/remanufacturing lot-sizing and supplier selection with returns,under carbon emission constraint

This paper addresses a lot-sizing problem in manufacturing/remanufacturing systems. The studied system is a single manufacturing line where both regular manufacturing and returns remanufacturing processes are carried out, with different set-up costs for each process. We consider also a returns collection phase from customers/distributors with deterministic returns quantities at each period of the planning horizon. The environmental aspect is assumed in this study by considering a carbon emission constraint for the manufacturing, remanufacturing and transportation activities. A mixed integer programming model to minimise the management cost and meet the customer’s needs under different manufacturing constraints is proposed. Otherwise, An adaptation of the well-known Silver and Meal (SM) heuristic and two hybrid method approaches (HM1 and HM2) providing approximates solutions are developed. The mixed integer model was tested on Cplex (Software optimizer), and the obtained results were compared with the ones provided by the adapted heuristic SM and the hybrid methods. The numerical analyses show that hybrid methods provide good-quality solutions in a moderate computational time. The proposed model establishes a collegial and an integrated process that sets values, goals, decisions and priorities along the considered supply chain while taking into account the environmental aspect.     

Comparative analysis and antibacterial properties of thermally sintered apatites with varied processing conditions

Hydroxyapatite (HA) and biphasic hydroxyapatite/beta-tricalcium phosphate (biphasic HA/β-TCP) were synthesized using thermal sintering. The parameters- sintering temperature (600°C, 900°C, and 1200°C), biological source used (fish bone, egg shells, and fish scales), and soaking time (2, 6, and 10 hours) were permuted to study their effects on the properties of the resultant apatite. Morphological study revealed that the smallest (60 nm) spherical particle and the largest (470 nm) irregular shaped particle were obtained from the fish bone sample sintered at 600°C and at 1200°C respectively. FTIR and XRD results showed that as the sintering temperature is increased, the phase transformation from HA to β-TCP takes place. Only the final products from fishbone sample at 600°C are pure carbonated HA. The crystallinity of synthesized particles ranged from 79% to 98%. Soaking time has no effect on phase composition of the apatite but has significant effect on crystallite size; increase in soaking time increases crystallite size and particle shape becomes more spherical. Interestingly, the fish bone sample sintered at 900°C has higher crystallinity and crystallite size compared to the fish scale sample sintered at the same temperature. EDX confirmed that non-stoichiometric apatite with Ca/P ratio ranging from 1.47 to 1.91 can be obtained by varying the sintering conditions. The antibacterial test revealed that both calcium apatite obtained from fish bones and fish scales have inhibited bacterial growth; apatite from fish bone works faster than fish scales. The in vitro cytotoxicity test ensured that all the calcium apatite except for eggshell are non-cytotoxic. Thus, apatite with excellent microbial activity can be obtained by using fish wastes, and by tuning the sintering parameters, the apatite with desired types and properties can be synthesized for different biomedical applications.     

Reasons for the Fast Growing Seawater Desalination Capacity in Algeria

Seawater/brackish water desalination has been widely adopted by the Algerian Government in the last few years to supply potable water to municipality for various purposes mainly for domestic and industrial uses especially in areas where demand is high due to shortage of fresh water resources, rapid population growth and development of industry and tourism. Ten years ago, desalination was confined to the industrial use only especially in oil and gas industry as the country was relying on rain water and other available sources to supply fresh water to municipalities. Due to chronic drought conditions, the Ministry of Water Resources reviewed the national water strategy and a strong option for desalination was adopted where an ambitious program was thus put into action. Sixteen mega-plants, with capacities ranging from 100,000 to 500,000 m³ per day, primarily based on Reverse Osmosis technology, were launched in the last few years making the Algerian desalination program one of the world’s fastest growing markets. Five desalination plants, including the Africa’s largest seawater reverse osmosis project with a total capacity of 200,000 m³ per day, are already in operation and the remaining projects are either under construction or in commissioning. An integrated water resources management was also adopted as additional option to cuter the increasing water demand as there is also a great potential for water reuse and conventional water treatment. An additional benefit of this would be reducing the volume of treated wastewater disposed into the environment.     

Fast computation of Charlier moments and its inverses using Clenshaw’s recurrence formula for image analysis

Multimedia Tools and Applications - In this paper, we propose a new fast way to compute both the image Charlier moments and its inverses using Clenshaw’s recurrence formula. Firstly, we...     

Image analysis by Meixner moments and a digital filter

Multimedia Tools and Applications - In this paper, we propose a new method for the rapid calculation of Meixner’s discrete orthogonal moments and its inverses. In this method, we have used...     

Synthesis and polymerization of the acrylamide derivatives of fatty compounds

The Ritter reaction of plant oil triglycerides (such as soybean and sunflower oil) with acrylonitrile was used to introduce acrylamide functionality on the triglyceride. Acrylonitrile and triglycerides were reacted in the presence of H₂SO₄, and acrylamide derivatives were obtained in yields of 45 and 50% for sunflower oil and soybean oil, respectively. Radical initiated copolymerization of the acrylamide derivatives of the triglycerides with styrene produced semirigid polymers. Characterization of new monomers and polymers was done by ¹H‐NMR, ¹³C‐NMR, IR, and MS. The swelling behavior of the crosslinked network polymers was determined in different solvents. Glass transiton temperature (T_g) of the cured resin was also determined by differential scanning calorimeter to be 40°C for soybean based polymer and 30°C for sunflower‐based polymer. Homo‐ and copolymerization behavior of acrylamide derivatives of methyl oleate (MOA) and methyl 10‐undecenoate (MUA) were also investigated. The reactivity ratios of these monomers with respect to styrene were determined by the Fineman–Ross method using ¹H‐NMR spectroscopic data. The reactivity ratios were r_sty = 1.776; r_moa = 0512 for MOA, and r_sty = 1.142; r_mua = 0.507 for MUA, respectively. Photopolymerization behaviors of MOA and MUA were also investigated using the photoDSC technique and the rate of polymerization of MUA is higher than that of MOA under the same conditions. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2264–2272, 2005     

Role of organic nitro compounds in selective reduction of NOx with ethanol over different supported silver catalysts

The adsorption of organic nitro compounds such as nitromethane and nitroethane on different supported silver catalysts (Ag/Al₂O₃, Ag/TiO₂, Ag/SiO₂) has been studied using infrared spectroscopy. The adsorbed NCO species formation was strongly influenced by the catalyst support and therefore clearly detected on Ag/Al₂O₃ and Ag/TiO₂ catalysts by thermal decomposition of nitromethane and nitroethane at temperatures higher than 150°C. With the Ag/SiO₂ catalyst, very little NCO formation was observed at 350°C. On the other hand, the catalyst support was found to affect the N₂ formation in the selective reduction of NO_x on supported silver catalysts. On the basis of these findings, the role of adsorbed nitromethane, nitroethane and isocyanate species in the selective reduction of NO_x is discussed with respect to the catalyst support effect and the catalytic activity. This revised version was published online in July 2006 with corrections to the Cover Date.     

Morphology,mechanical, and physical properties of wet-spun cellulose acetate fiber in different solvent-coagulant systems and in-situ crosslinked environment

Wet spinning is a popular fiber manufacturing process where the effects of solvent and coagulant on the wet-spun fiber are significant. In this study, we have explored the effect of solvent-coagulant interaction and in-situ crosslinking on the wet-spun cellulose acetate (CA) fiber. Investigation on 12 different solvent-coagulant systems revealed that variation in the systems resulted in significant variance in morphology and mechanical property of the fiber. Remarkable increase in mechanical property was observed after in-situ crosslinking with citric acid and polyethylene glycol (PEG). Inclusion of sodium hypophosphite (NaH₂PO₂) as catalyst further increased tensile modulus (~407%) and crystallinity index (~46%) compared to CA fiber crosslinked with only citric acid. It was established that fiber from CA-DMSO solution crosslinked with 10% citric acid and 10% PEG extruded in ethanol showed the highest tensile modulus (~30 MPa). This in-depth study found an appropriate combination of solvent-coagulant for forming stable CA fiber, with the addition of crosslinkers and catalyst further increasing the strength and usability of the fiber.     

A multidisciplinary ensemble algorithm for clustering heterogeneous datasets

Neural Computing and Applications - Clustering is a commonly used method for exploring and analysing data where the primary objective is to categorise observations into similar clusters. In recent...