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Despite the uncertainties of the energy market impacted by the collapse of oil prices and a sharp increase in domestic energy consumption, Algeria continues to make huge efforts to bring energy access to its people. At the same time, the country is also witnessing a very slow start of the energy transition, which brings into question the energy‐intensive development model accused of contributing both to global warming and to the depletion of fossil resources in the medium and long term. Although quantified targets are set, the National Program for the Development of Renewable Energies (NPDRE) struggles to take off and is lagging behind. There is no doubt that the recent fall in oil prices will further complicate the achievement of this transition; still one may raise the question of whether other barriers to the NPDRE should not be removed. Admittedly, the Algerian State has set up an incentive mechanism based on feed‐in‐tariffs to boost the NPDRE, but this failed to attract potential investors. This paper seeks to analyze the reasons for these failures as well as other issues linked with the energy–water–food trilemma. There are plenty, but the heavily subsidized energy products appear to be the most disabling.

The aim of this work was to formulate and optimize the washing performance of an alkylpolyglucoside-based dishwashing detergent. The liquid detergent was formulated with five ingredients of commercial origin: anionic (linear sodium alkylbenzenesulfonate and sodium laurylethersulfate), nonionic (C 12 -C 14 alkylpolyglucoside) and zwitterionic (a fatty acid amide derivative with a betaine structure) surfactants, and NaCl for viscosity control. In addition to the plate test, other properties were investigated including ''cloud point'', viscosity, and emulsion stability. Statistical analysis software was used to generate a central composite experimental design. Then, a second order design and analysis of experiments approach, known as the Response Surface Methodology, was set up to investigate the effects of the five components of the formulation on the studied properties in the region covering plausible component ranges. The method proved to be efficient for locating the domains of concentrations where the desired properties were met.

Yeast strains were isolated from sugar cane molasses (S1), dates (S2) and figs (S3) and the ethanol production was evaluated in batch condition. A comparison was made with the yeast Saccharomyces cerevisiae. The strains showed tolerant characteristics to stressful conditions like salinity and ethanol. The isolated strains produced ethanol; at 20 h of fermentation ethanol yields were 0.38-0.39 g.g-1 , and the productivities were almost 0.58 g.L-1. S. cerevisiae and S1 tolerated up to 14% (v/v) of ethanol; while interestingly the isolates S2 and S3 were highly tolerant, up to 20% (v/v) ethanol. Thus, S2 and S3 could serve as potential strains for ethanol fermentation, with 0.27 and 0.29 g.g-1 yield of ethanol in the presence of 1.37 mol.L-1 NaCl. These values were higher than the value obtained using the yeast of reference and S1 (0.16 g.g-1). Co-cultures of S2 and S3 enhanced the ethanol production, increasing the yield of ethanol by 12.5% compared with the single culture. The strains were identified as species S.cerevisiae, and S2 and S3 were very similar. For an application in the valorization of biomass such as green macro-algae, some assays were done on a synthetic model medium of hydrolysate of macro-algae and the strains S2 and S3 demonstrated excellent fermentative performances.

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Résumé L’émulsion est une forme très répandue dans les applications pharmaceutiques et cosmétiques, et les tensio‐actifs synthétiques utilisés pour stabiliser ce système dispersé posent un problème écologique. L’émulsion stabilisée par des particules solides (émulsion de Pickering) vient pour régler ce problème. Cette étude vise à réduire la teneur en tensio‐actif dans les formulations des émulsions pharmaceutiques et cosmétiques. La stabilité physique (stabilité au crémage) d'une émulsion de Pickering H/E utilisant des particules solides de bentonite en combinaison avec un tensio‐actif cationique (CTAB) et en présence de sel (NaCl) a été optimisée à l'aide de la méthodologie des surfaces de réponses. Les résultats montrent qu'une teneur de 7 % de particules solides en présence de faibles concentrations en tensio‐actif cationique (CTAB, 0.02 %) et en sel (NaCl, 0.015 mol/L) permet d'obtenir une stabilité physique satisfaisante après 22 mois de vieillissement. En outre, la température qui a une influence directe sur la viscosité du milieu lors de la préparation, est déterminante pour l'obtention d'une émulsion stable. Ainsi, une émulsion de Pickering préparée à 50 °C montre une stabilité comparable à celle d'une émulsion préparée à 20 °C et contenant deux fois plus d'agents stabilisants.

The response surface methodology (RSM) was used to optimize the washing performance, viscosity, (cloud point) and turbidity of a model hand dishwashing (light duty) liquid detergent. Homogeneous mixtures of four ingredients represented typical formulations: an anionic surfactant (sodium linear alkylbenzenesulphonate, LAS, MW ∼350), a nonionic surfactant (C16 – C18 range ethoxylated alcohol with 11–12 EO), a 80/20 v/v glycerol/water mixture and an inorganic electrolyte (NaCl). The Statistica® software, and especially its (Design of Experiments) module, was used to model the above-mentioned properties (response functions) and to find out the best formulation with the help of the desirability profiler. RSM mainly helps to select regions of the experimental design where cloud point values are acceptable. Results show that, at high levels of anionic species, cloud point values are very sensitive to salt addition.

Ultrarapid anodic dissolution of silicon in HF-free solutions is reported. Although the etch rates are insignificant up to a potential of 25 V, when shifting the potential to higher values of 35-55 V the silicon etch rate reached a record value of more than 30 m/min. In addition, surface morphologies are notably affected by the applied potential, modifying the surface from a porous one to a partially polished one.The development of a rapid and relatively inexpensive process for the fabrication of three-dimensional structures from silicon wafers is of great interest. 1,2 One of the most effective techniques for the fabrication of three-dimensional structures is electrochemical etching, 3-5 which offers the following advantages over other etching techniques: wide variations in etch rate and accurate control and monitoring of the etching processing. Here, we demonstrate the use of a rather simple electrochemical route for silicon etching by applying positive ͑anodic͒ potentials during conditions of wet etching in acid-free solutions. The application of anodic bias results in a fast etching rate with a silicon removal rate value of 32 m/min. Silicon anodizing is capable of forming a polished or a textured silicon surface, including porous structures. The combined effects of both high potential and alkaline concentrations are primarily responsible for overcoming silicon passivation ͑formation of an oxide layer͒ and the extreme etching rates.Traditional electrochemical etching is usually associated with anodic polarization; the treated material potential is being positively shifted within the active dissolution potential range, which can be referred to as the active potential window. The wider this potential window is, the higher the etching rate. Considering silicon, a wide potential range of active anodic dissolution occurs only in solutions containing HF. 6 In HF-free aqueous solutions, silicon is either totally passive or active only in a narrow anodic potential window, with an inability to adjust the etching rate, as is the case, for example, in strong alkaline solutions. 7,8 Thus, it may appear that Si electrochemical etching is largely ineffective in solutions other than HF. However, it was established in our previous studies that a significant acceleration of silicon dissolution rate can be achieved in alkaline solutions under the application of extremely negative voltages. 9,10 For example, an etch rate above 4 m/min was obtained in alkaline solution at potentials of Ϫ30 V ͓saturated calomel electrode ͑SCE͔͒ and lower. 10 At first glance, consideration and attempt to accelerate silicon etching using anodic polarization is doomed to fail because in HFfree solutions, silicon is being anodized with the formation of silicon oxide film in a wide potential range. In many acidic and neutral aqueous solutions, silicon breakdown occurs at potentials above 100 V. 11 However, in alkaline solutions, the potential region available for silicon anodization is very limited. For example, in 1 and 2 M KOH, the potential region ...