• Energy Research
• medical and health sciences close
• EU close
• FR close
• English close

Observations with imaging atmospheric Cherenkov telescopes (IACTs) have enhanced our knowledge of nearby supernova (SN) remnants with ages younger than 500 yr by establishing Cassiopeia A and the remnant of Tycho’s SN as very-high-energy (VHE) γ-ray sources. The remnant of Kepler’s SN, which is the product of the most recent naked-eye SN in our Galaxy, is comparable in age to the other two, but is significantly more distant. If the γ-ray luminosities of the remnants of Tycho’s and Kepler’s SNe are similar, then the latter is expected to be one of the faintest γ-ray sources within reach of the current generation IACT arrays. Here we report evidence at a statistical level of 4.6σ for a VHE signal from the remnant of Kepler’s SN based on deep observations by the High Energy Stereoscopic System (H.E.S.S.) with an exposure of 152 h. The measured integral flux above an energy of 226 GeV is ∼0.3% of the flux of the Crab Nebula. The spectral energy distribution (SED) reveals a γ-ray emitting component connecting the VHE emission observed with H.E.S.S. to the emission observed at GeV energies with Fermi-LAT. The overall SED is similar to that of the remnant of Tycho’s SN, possibly indicating the same nonthermal emission processes acting in both these young remnants of thermonuclear SNe. Astronomy and astrophysics 662, A65 (2022). doi:10.1051/0004-6361/202243096 Published by EDP Sciences, Les Ulis

Description of the subject. Extracellular enzymes from filamentous fungi are increasingly used in eco-friendly biotransformation processes. Their relevant technological role and their stability towards extreme process conditions make of them the first sustainable solution for the elaboration of bio-based products from biomass conversion. Objectives. This paper describes the isolation of filamentous fungi from decaying plant material in the region of Meknes (northern central Morocco) and the assessment of their ability to breakdown lignocellulose. The objective is to select performant fungi with enzymatic machinery adapted to local environment and with potential for the breakdown of the regional specific lignocellulosic by-products into potentially high-value molecules. Method. Cereals, decaying wood, olive-pomace and -pulp and their composts were used to isolate lignocellulolytic fungi. One hundred twenty-seven pure strains were isolated and screened at 25 °C on selective media with cellulose or lignin as the sole carbon source. Performant strains were validated for the production of ligno-cellulolytic enzymes and identified using molecular technique. Results. Twenty-eight fungi had mycelial diameter on cellulose ≥ 6 cm and cellulolytic index ≥ 0.9. Twenty-two strains had the same profile on lignin medium. The production of endoglucanase, lignin peroxidase and manganese peroxidase enzymes was confirmed in performant strains using qualitative assay and molecular identification revealed that the best performing fungi were Mucor circinelloides, Mucor racemosus, Penicillium brasilianum, Penicillium crustosum, Paecilomyces sp., Fusarium oxysporum, Fusarium solani, Aspergillus fischeri, Curvularia spicifera, Humicola grisea, Trichoderma atroviride and Cosmospora viridescens. Measurement of ligno-cellulolytic activities revealed that Penicillium and Fusarium strains mainly from wood decay and compost had the best profiles among performing strains. Conclusions. Isolated fungi are high decomposers of biomass and represent a prominent solution to develop green bioprocesses in the region.

In this paper we present an optical characterization for quantum dot intermediate band solar cells (QDIBSCs). The cells were developed by growing a stack of ten InAs/GaAs QDs layers between p and n doped GaAs conventional emitters. Electroluminescence, EL, photoreflectance, PR, and transmission electron microscopy, TEM, were applied to the samples in order to test and characterize them optically. The results, derived from the application of the different techniques, showed a good correlation. TEM images revealed a very good structural quality of the QDs, which seem to evolve in shape-strain from the bottom to the top of the stack. Corresponding to the quality observed by TEM, strong signals from EL and PR resolved unambiguously the energy band diagram of the QDIBSCs. By fitting PR data we were able to indentify the coexistence of bands and discrete energy levels coming from the IB material. The PR data evidenced also a strong electric field over the dots, attributed to the space charge region created between the p-n emitters sandwiching the IB material. From EL results, we identified the predominantly radiative nature of the IB material related energy transitions. 23rd European Photovoltaic Solar Energy Conference and Exhibition, 1-5 September 2008, Valencia, Spain; 298-301

The landscape of supply chain and logistics is changing at the fast past than ever due to digitalization. Everyday, new technologies are emerging and having impact on how logistics activities will be carried out. Furthermore, the acceptance of these technologies depends on the initial perception of stakeholders in logistics. This presentation outlines impact of nine various emerging technologies on future of logistics as perceived by experts in supply chain and logistics. - Results were presented during the 13th ITS European Congress special session.

The objective of this study was to evaluate the feasibility of an aqueous process for the biorefinery of sunflower whole plant using a twin-screw extruder. Aqueous extraction of oil was chosen as an environment-friendly alternative to the solvent extraction. The extruder was used to carry out three essential unit operations: grinding, liquid/solid extraction, and liquid/solid separation. Wringing out the mixing was effective. However, drying of the cake meal was not optimal. Lixiviation of cotyledon cells was also incomplete. Extraction efficiency depended on operating conditions: screw rotation speed, and input flow rates of whole plant and water. In the best conditions, oil yield was 57%. Residual oil content in the cake meal was 14%. These conditions leaded to the co-extraction of proteins, pectins, and hemicelluloses. The corresponding protein yield was 44%. Oil was extracted in the form of two oil-in-water emulsions. These hydrophobic phases were stabilized by phospholipids and proteins at interface. An aqueous extract containing part of the water-soluble constituents, mainly proteins and pectins, was also generated. As a mixture of fibers and proteins, the cake meal was molded by thermo-pressing. Panels produced had interesting mechanical properties in bending. The obtained fractions may have applications as bases for industrial products. Proceedings of the 18th European Biomass Conference and Exhibition, 3-7 May 2010, Lyon, France, pp. 1481-1489

We consider next generation solar cells concepts those that have the potential to exceed the limiting efficiency calculated by Shockley and Queisser for single gap solar cells (40.7 %) and still have not been commercialized. Among these concepts, this paper deals with the multiple exciton generation (or impact ionization or multiple carrier generation) solar cell, the intermediate band solar cell and the hot carrier solar cell. These concepts were proposed theoretically more than ten years ago. In the last years, the number of experiments supporting the theories behind and paving the way towards their practical implementation has leaped forward. This work reviews these experimental advances. 25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 4-9

The ButaNexT project aims to demonstrate the techno-economic feasibility of the conversion of two sustainable lignocellulosic feedstocks (wheat straw and miscanthus) available at EU level, into biobutanol through the integration of different technology developments. The project has ended recently and the main achievements of the consortium have been the following: (1) design, construction and operation of a micronizing pilot prototype for controlled biomass particle size production up to 0.5 mm with a more reduced energy consumption and able to be scalable to industrial size; (2) development of a flexible and easy to adapt two-step fractionation process based on the combination of the micronizing prototype with a continuous thermochemical pretreatment; (3) development of tailored enzyme cocktails (MetZyme® SUNO™) that address harsh process-specific conditions and facilitate improved hydrolysis of pretreated biomass to monosaccharides; (4) development of a Clostridial strain able to ferment cellulosic sugars effectively (target butanol yield > 0.25 g/g pure sugar) and having 20% higher butanol tolerance than baseline strain; (5) development of a patent-pending “In situ product recovery process” based on improved pervaporation fluxes obtained during fermentation that allows continuous operation; (6) validation of the technical performance of the individual stages cited above in a pilot facility using wheat straw as feedstock from handling to product recovery in a 100 L bioreactor; (7) testing of properties and performance of butanol as a blend component in both diesel and gasoline fuels and (8) calculation of GHG emissions of biobutanol in a number of different scenarios based on the use of wheat straw and miscanthus as feedstocks and for the provision of heat, electricity and waste water treatment. Proceedings of the 26th European Biomass Conference and Exhibition, 14-17 May 2018, Copenhagen, Denmark, pp. 984-990

This work, carried out at Research Centre for Industrial Crops of CREA in Rovigo, aimed at assessing the performance of a modified combine header and seed losses during late harvest of 5 hemp varieties. The renewed interest in Italy for hemp cultivation is aimed at seed production unlike the traditional cultivation aimed at fibre. However, it must face the lack of monoecious varieties suitable for Italian environment. In the case of dioecious varieties, traditionally cultivated in Italy for fibre production, the high crop height makes it difficult the mechanical harvesting with conventional combines. Similarly, the uneven height recorded in the case of imported varieties for seed production, requires adjusting continuously the height of the combine header. So, modified combine headers capable of be moved upwards and downwards by a lift have been developed. The aim is to avoid the risk of possible clogging of threshing apparatus introducing big pieces of stalks. Moreover, in this way, the stalks can be harvested separately in order to increase the income for farmers. In view of valorise the whole plant, as multipurpose crop, the right harvest time should be a trade-off between seed yield and fibre quality. Early harvesting guaranties a good fibre quality but causes also the harvest of seed not completely ripened. On the contrary delaying the harvest reduces the seed yield due to seed loss for dehiscence. In addition to losses for dehiscence prior to harvest, the trials aimed at distinguishing the loss incurred during harvest attributable both to crop disturbance by combine header and to the setting of the combine’s threshing and separation elements. Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 197-200