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In the present study, the effects of feeding 450 g/day of rumen-protected fish oil (FO) compared to sunflower oil (SO) to Angus heifers (60 g/kg total intake) were quantified. Animal performance was not affected whereas the physico-chemical meat quality, assessed in three muscles, was slightly affected by diet. The oxidative shelf life of the perirenal fat declined with FO compared to SO. Despite the formerly shown increased n –3 fatty acid proportions of meat due to FO supplementation, a trained sensory panel identified an only slightly more intense fishy flavour in grilled steaks and beef patties from the FO compared to the SO group. In FO compared to SO patties, flavour intensity was more pronounced. The perception of off-flavours was negligible and differences between muscles were larger than between diets. In conclusion, supplementing ruminants with FO containing nutritionally beneficial n –3 fatty acids results in few side-effects on meat quality, restricted to quite faint off-flavours and a shorter fat shelf life. • Exchange of rumen-protected sunflower oil for fish oil was tested in beef heifers. • Effects on performance and physico-chemical quality of the beef were small. • The use of fish oil reduced the oxidative stability of the body fat by one third. • Grilled steaks and beef patties were perceived slightly more fishy with fish oil. • Sensory attributes differed more between muscles than between oil types. [ABSTRACT FROM AUTHOR]

The organo-acid-activated bentonite (OAB) was prepared and characterized by SEM, XRD, FTIR, pHPZC and BET. Then the OAB was employed as adsorbent for the removal of bisphenol A (BPA) and 2,4,5-trichlorophenol (TCP) from aqueous solutions. The adsorption performances of OAB were investigated by batch mode experiments with respect to pH, temperature, initial concentration, contact time and competitive adsorption. The Langmuir model describes better the results of BPA adsorption while the results of TCP are best fitted to Freundlich model. The maximum adsorption capacities are found to be 127.7 and 244.6 mg/g for BPA and TCP, respectively. The kinetic properties were well described by the pseudo-second-order equation.Thermodynamic parameters suggest that the adsorption process of BPA and TCP onto organoclay (OAB) are physisorption, spontaneous and exothermic. In binary solutions, BPA and TCP show competitive adsorption. Hydrophobic interaction play an important role during the sorption process. In addition, OAB could be regenerated and reused for adsorption of BPA/TCP again. [ABSTRACT FROM AUTHOR]

The study of the reliability of PV systems, although they are answered in the world, is rare. In Algeria we have recorded any university research laboratory on the subject, despite the government gives great importance to the development of PV systems from us. It is therefore important to know the reliability, availability and sustainability of these systems. This will help to objectively determine the lifetime of a PV system before the costs become more important than the gains from the system. The objective of this work is to calculate the reliability of the MPPT of PV system and simulate the combination of a photovoltaic panel with a DC/DC converter controlled by the technical Disrupts & Regards. Two choppers are available for study parallel (three conduction modes and three powers), and the chopper Cuk (for the same power). [ABSTRACT FROM AUTHOR]

Abstract: A potential solution for stand-alone power generation is to use a hybrid energy system in parallel with some hydrogen energy storage. Renewable energy sources (solar, wind, etc) are attracting more attention as alternative energy sources to conventional fossil fuel energy sources. This is being used widely for substitution of oil-produced energy and will help to minimize atmospheric degradation. One third of the world population does not have access to clean water sources and most of these people are not connected to the electrical grid at the same time. In this paper, a hybrid Photovoltaic (PV)-fuel cell generation system employing an electrolyzer for hydrogen generation is designed and simulated. The system is applicable for a desalination plant loads. Reverse osmosis (RO) is an electrically driven technology characterized by significantly low specific power requirements. In the meantime, coastal arid areas are blessed with exceptionally high solar radiation most of the year. Normally, those areas have no access to municipal water network and the local power grid. Thus, the water problem can also be seen as an energy problem since seawater, brackish water or freshwater of unknown quality are abundantly available but significant amounts of energy are required in order to make it suitable for drinking. Photovoltaic (PV) powered water purification is an opportunity to solve this issue. It can provide potable water and on top, small independent minigrids that supply people with electricity, too. The proposed configuration, even if it is not entirely autonomous still requires a smaller area of solar panel to operate. By cons, there remains the problem of the source of hydrogen. If hydrogen is not produced by electrolysis but by reforming hydrocarbons, this means CO2 emissions, with resources that are not inexhaustible. Moreover, 95% of the hydrogen currently produced using this method. For a massive use of hydrogen consumption, it will consider new production methods, such as the construction of nuclear power plants dedicated to hydrogen production with such high-temperature electrolysis. [Copyright &y& Elsevier]

Abstract: We studied the blend formed by electrochemical polymerization of bithiophene monomer (BTh) on electrolytic manganese dioxide (γ-MnO2). The composite material (PBTh/γ-MnO2) has been synthesised in 0.01M PBTh/0.1M LiClO4/CH3CN by chronoamperometry test at oxidation potential 1.1V vs. saturated calomel electrode during 20min, and then characterized by different methods including cyclic voltammetry, impedance spectroscopy, FTIR spectroscopy, and magnetic measurements. These blends have been tested as positive electrode in Zn//γ-MnO2 cells. Good discharge performance was obtained with the modified MnO2, which exhibits better active material; increasing cell capacity is observed. [Copyright &y& Elsevier]

A one-dimensional simulator Analysis of Microelectronic and Photonic Structures in 1 Dimension (AMPS-1D) has been used so as to investigate cadmium telluride (CdTe) based solar cells properties. The aim of the current study is to explore the possibility of improving the efficiency of the solar cells. For that purpose, a novel back surface field (BSF) SnS layer has been inserted after the back contact (Ni) in CdTe solar cells constituted by a pile of thin layers that contains in particular a fine layer called buffer layer (CdS) between the absorber layer CdTe and the windows layer ZnO-Al. The optimal values ​that​ give the maximum performance of the structure ZnO/CdS/CdTe/SnS/Ni, with and without a BSF layer (SnS) has been determined. Our results show an improvement of the efficiency of the solar cell when using the BSF. The proposed cell with SnS layer is found to give an efficiency of 21.83% using only thicknesses of 0.6 μm and 0.4 μm for CdTe and SnS, respectively. However, the efficiency of the cell reference (without BSF) is 17.40% with a thickness of 1 μm for the absorber layer CdTe. Moreover, the normalized efficiency of the proposed cells with BSF layer decreases linearly with increasing the temperature, suggesting a better stability of the ultra thin cells. [ABSTRACT FROM AUTHOR]

Abstract: The proton diffusion coefficient for both fresh and heat-treated (140 and 230°C, respectively) α and β-PbO2 electrodes was estimated at room temperature using Galvanostatic Intermittent Titration Technique (GITT). PbO2 samples were prepared by electroformation of cured plates. HSbO3·xH2O with a conductivity of 3.29×10−3 Ω−1 cm−1, was used as solid protonic conductor (SPC) electrolyte. It was found that when structural water is removed, the capacity of both α and β-PbO2 electrodes decreases and the ohmic drop increases. The departure of structural water affects considerably the value of proton diffusion coefficient. [Copyright &y& Elsevier]

The study used 81 young bulls, half of which were disbudded at 7 weeks of age. The effects of horn status during rearing and of acute physical and emotional stress just before slaughter on the physiological status at slaughter and subsequent meat quality were investigated. Bulls were reared in groups containing i) only bulls with horns, ii) only bulls without horns, or iii) mixed (half with, and half without horns). Bulls of each rearing condition were assigned to one of two slaughter conditions: with limited (LS) or with supplementary stress (SS). LS resulted in lower heart rates, stress hormone concentrations and carcass temperature, whereas SS resulted in faster post mortem pH decline and lower juiciness. Horned bulls from unmixed rearing groups had lower early pm temperature, shorter sarcomeres, and lower tenderness compared to disbudded bulls. Correlations and regression analysis revealed relationships between physiological indicators, mainly heart rate before slaughter, and meat quality, including water-holding capacity and indicators of proteolysis. • Pre-slaughter animal stress reduced beef juiciness. • Relationships between pre-slaughter physiological status and meat quality • In homogenous rearing groups: tougher meat in horned than disbudded bulls • Bulls of mixed rearing groups: less reactive to pre-slaughter stress [ABSTRACT FROM AUTHOR]