• Energy Research
• 2021-2025close
• 13. Climate action close
• Hyper Article en Ligne close

Once previous industrial activity has ceased, brownfields are found in urban and suburban environments and managed in different ways ranging from being left untouched to total reconversion. These situations apply to large surface areas often impacted by residual diffuse pollution. Though significant and preventing any sensitive use, residual contamination does not necessarily require treatment. Moreover, conventional treatments show their technical and economic limits in these situations and gentle remediation options such as phytomanagement might appear more relevant to the management of those sites. Thus, these sites face up two major issues: managing moderate contamination levels and providing an alternative use of economic interest. This work proposes to assess a management strategy associating the phytoremediation of organic pollution along with the production of biomass for energy generation production. A 16-week controlled growth experiment was conducted on a soil substrate moderately impacted by multiple pollution (trace elements, mainly Zn and Pb, and hydrocarbons), by associating rhizodegradation with Medicago sativa or biomass production with Robinia pseudoacacia or Alnus incana in monocultures. The effect of a microbial inoculum amendment on the performances of these treatments was also evaluated. Results showed total hydrocarbons (TH), and to a lesser extent polycyclic aromatic hydrocarbons (PAH), concentrations decreased over time, whatever the plant cover. Good biomass production yields were achieved for both tree species in comparison with the control sample, even though R. pseudoacacia seemed to perform better. Furthermore, the quality of the biomass produced was in conformity with the thresholds set by the legislation concerning its use as a renewable energy source.

Once previous industrial activity has ceased, brownfields are found in urban and suburban environments and managed in different ways ranging from being left untouched to total reconversion. These situations apply to large surface areas often impacted by residual diffuse pollution. Though significant and preventing any sensitive use, residual contamination does not necessarily require treatment. Moreover, conventional treatments show their technical and economic limits in these situations and gentle remediation options such as phytomanagement might appear more relevant to the management of those sites. Thus, these sites face up two major issues: managing moderate contamination levels and providing an alternative use of economic interest. This work proposes to assess a management strategy associating the phytoremediation of organic pollution along with the production of biomass for energy generation production. A 16-week controlled growth experiment was conducted on a soil substrate moderately impacted by multiple pollution (trace elements, mainly Zn and Pb, and hydrocarbons), by associating rhizodegradation with Medicago sativa or biomass production with Robinia pseudoacacia or Alnus incana in monocultures. The effect of a microbial inoculum amendment on the performances of these treatments was also evaluated. Results showed total hydrocarbons (TH), and to a lesser extent polycyclic aromatic hydrocarbons (PAH), concentrations decreased over time, whatever the plant cover. Good biomass production yields were achieved for both tree species in comparison with the control sample, even though R. pseudoacacia seemed to perform better. Furthermore, the quality of the biomass produced was in conformity with the thresholds set by the legislation concerning its use as a renewable energy source.

AbstractMid‐infrared lasers have important applications in infrared countermeasures, sensing, environmental monitoring, biomedicine, and many military and civilian fields. In this work, an intense emission at 2.9 μm from Yb3+/Ho3+ co‐doped TeO2‐Ga2O3‐ZnO (TGZ) glass was reported. The 2 μm, 1.2 μm and visible emissions were also performed to understand the competitive luminescent mechanism. With the increase in Yb3+ concentration, all the emissions of Ho3+ increased, whereas the emission of Yb3+ decreased due to the phonon‐assisted energy transfer from Yb3+ to Ho3+. The lifetimes of optimized 3 mol% Yb2O3 and 1 mol% Ho2O3 co‐doped TGZ glass, which has the maximum emission intensity, are 548 μs and 1.7 ms at 2.9 and 2 μm, respectively. The Judd–Ofelt intensity parameters, absorption, and emission cross sections were calculated to evaluate the mid‐infrared fluorescence properties of this new glass matrix material. The gain coefficients show that the 2 and 2.9 μm laser gain can be realized by small pump energy, indicating that this glass is a promising medium for the mid‐infrared optical fiber laser.

AbstractMid‐infrared lasers have important applications in infrared countermeasures, sensing, environmental monitoring, biomedicine, and many military and civilian fields. In this work, an intense emission at 2.9 μm from Yb3+/Ho3+ co‐doped TeO2‐Ga2O3‐ZnO (TGZ) glass was reported. The 2 μm, 1.2 μm and visible emissions were also performed to understand the competitive luminescent mechanism. With the increase in Yb3+ concentration, all the emissions of Ho3+ increased, whereas the emission of Yb3+ decreased due to the phonon‐assisted energy transfer from Yb3+ to Ho3+. The lifetimes of optimized 3 mol% Yb2O3 and 1 mol% Ho2O3 co‐doped TGZ glass, which has the maximum emission intensity, are 548 μs and 1.7 ms at 2.9 and 2 μm, respectively. The Judd–Ofelt intensity parameters, absorption, and emission cross sections were calculated to evaluate the mid‐infrared fluorescence properties of this new glass matrix material. The gain coefficients show that the 2 and 2.9 μm laser gain can be realized by small pump energy, indicating that this glass is a promising medium for the mid‐infrared optical fiber laser.

AbstractShifting from a linear to a circular bio‐economy requires new business models. The objective was getting insights into the uncharted research field of business model innovation for a circular and sustainable bio‐economy within the agrifood sector. Eight European cases valorising agricultural waste and by‐products by closing loops or cascading were studied regarding their innovation drivers and elements, via interviews, on‐site visits and secondary data. In this domain, the findings highlight that business model innovations are depending on the (i) macro‐environmental institutional‐legal conditions and market trends, (ii) driven by internal economic, environmental and/or social objectives, but especially strongly linked to (iii) other actors often from different sectors seeking synergies and (iv) value co‐creation via combined organisational and technological innovations. Business models for a circular bio‐economy thus depend on various action levels and need radical combined organisational and technological innovations for a most efficient usage of agricultural waste and by‐products. This also means new business configurations instead of linear innovation strategies currently still being dominant due to economic viability.

AbstractShifting from a linear to a circular bio‐economy requires new business models. The objective was getting insights into the uncharted research field of business model innovation for a circular and sustainable bio‐economy within the agrifood sector. Eight European cases valorising agricultural waste and by‐products by closing loops or cascading were studied regarding their innovation drivers and elements, via interviews, on‐site visits and secondary data. In this domain, the findings highlight that business model innovations are depending on the (i) macro‐environmental institutional‐legal conditions and market trends, (ii) driven by internal economic, environmental and/or social objectives, but especially strongly linked to (iii) other actors often from different sectors seeking synergies and (iv) value co‐creation via combined organisational and technological innovations. Business models for a circular bio‐economy thus depend on various action levels and need radical combined organisational and technological innovations for a most efficient usage of agricultural waste and by‐products. This also means new business configurations instead of linear innovation strategies currently still being dominant due to economic viability.