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A device for catching insects, using a high voltage electrical discharge, called KAHRATRAP, is designed and build up by the first author of this paper. The aim of this paper is to describe the electrical operation mode of this apparatus such as the high voltage supply and the electrical discharge which this supply produces for the elimination of insects. We determined in this paper the most optimal color of the lamps of the device which give the best results. Moreover, we analyze the influence of climatic parameters such as temperature and humidity on the efficiency of the process. This apparatus was used during 4 months in a vegetable field, operating during the night from 18h to 6h to capture harmful insects. The reading of insect numbers is done according to a procedure using a binocular magnifying glass, an entomologist tool and boxes for the collection of insects.

In order to find the electrical size which determined the critical condition of flashover, the authors have examined the propagation of the discharge on surface under dc voltage in a new laboratory model which has a continuous and radial current distribution. This model is a vat having a circular sector form of variable angles, radiuses and depths filled by an electrolyte. The obtained results on this model show that for a given resistivity of electrolyte: --If the current distribution in the horizontal plane is uniform according to the sector angle, the applied critical voltage and the critical current per unit of angle (1[degrees]) are constant for all sectors of various angles. --If the current distribution in the vertical plane is uniform according to the depth, the critical flashover voltage and the critical current per unit of the electrolyte depth (1mm) are constant for all the depths. These results lead to the critical conditions of flashover to be determined by the current per unit of angle and per unit of electrolyte depth (A/[degrees]/mm). Index Terms--Flashover, insulator, discharge, electrolyte, current distribution.

Global energy consumption is projected to increase, even in the face of substantial declines in fossil energy intensity, at least 2-fold by midcentury relative to the present because of population and economic growth. Currently the world's growing thirst for oil amounts to almost 1000 barrels a second. The ever increasing world energy demand cannot be satisfied much longer with fossil fuels. Achieving solutions to energy problem that we face today requires long-term potential actions for sustainable development. In this regard, renewable energy (RE) resources appear to be crucial and the one of the most efficient and effective solutions for sustainable development. That is why a shift to a more sustainable mix by means of the use of RE sources, an increase of the energy efficiency, energy sobriety and greenhouse gas mitigation measures is needed. The development of technological innovation in the energy fields is central to the success of the energy paradigm shift worldwide. Among RE resources, solar energy is by far the largest untapped resource and major primary energy exploitable resource. Algeria has the highest average solar radiation per square meter of any country in the world and is an interesting case study in that it had quite a slow start in this field but is now forging ahead with RE -at least at the utilities level, boosted by government policy. Progress at residential level is not as fast, though. This has to be rectified for the country to meet the targets set in its National Development Plan. A broad range of intensive and promising research and development is being conducted, under the Sahara Solar Breeder (SSB) project concept, in order to produce technological options that can allow energy security, climate stabilisation and economic development from solar energy. In view of the intermittency of insolation, SSB project provides an especially attractive approach in which solar energy must be dispatched on demand to the end user using High Critical Temperature Supra Conductor (HTcSC) cables. The magnitude of such implied infrastructure transition suggests the need for massive investments in innovative energy research. Anticipated patterns of future energy use and consequent environmental impacts are comprehensively discussed in this article. Also, potential solutions to current problems are identified along with the adoption of the SSB project plan and activities. The relations between RE and sustainable development are described with practical cases of SSB energy policy and its portfolio directed towards continental and global clean energy supply with existing solar grade Silicon production from Sahara sand and diatoms technologies making photovoltaic (PV) a significant contributor within a portfolio of energy sources in the coming 10 to 50 years. An illustrative example of some developed SSB key innovative technologies is presented and more should be challenged together, Algerian and Japanese SSB research teams, to seek the paradigm shift in global energy production and transport system. In both cases, the research is emanating from the University of Sciences and Technology of Oran (USTO-MB) in line with Saida University. [ABSTRACT FROM AUTHOR]

The growing demands for improved fire safety, source material sustainability, environment friendliness, and asset life extension have driven the research and development efforts of synthetic esters, less-flammable fluids. However the relatively limited number of work on these esters and their cost still limit their uses to specific applications. This contribution reports some investigations onto the Electrostatic Charging Tendency (ECT) of a commercially available ester fluid. Comparison is made with mineral oil, as this is a fluid we are familiar with. Fresh (unaged) and aged fluid samples were investigated in a spinning disk system under laboratory controlled conditions. Changes in static electrification were compared to some aging indexes (interfacial tension, turbidity, relative dissolved decay products). This contribution is not only intended to provide a fresh review in this domain of research, but also contains a substantial amount of new material with a view of closing some gaps in the present state of knowledge of oil streaming electrification. The obtained results show that static electrification currents are affected by fluid motion velocity, type of paper, moisture content and the aging byproducts. It was also found that the removal of dissolved oxygen by nitrogen blanketing contributed to the reduction in static electrification. [ABSTRACT FROM AUTHOR]