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The syntheses of 4,4′-bis(4-dimethylaminophenyl)-6,6′-dimethyl-2,2′-bipyridine (1), 4,4′-bis(4-dimethylaminophenylethynyl)-6,6′-dimethyl-2,2′-bipyridine (2), 4,4′-bis(4-diphenylaminophenyl)-6,6′-dimethyl-2,2′-bipyridine (3), and 4,4′-bis(4-diphenylaminophenylethynyl)-6,6′-dimethyl-2,2′-bipyridine (4) are reported along with the preparations and characterisations of their homoleptic copper(I) complexes [CuL2][PF6] (L = 1–4). The solution absorption spectra of the complexes exhibit ligand-centred absorptions in addition to absorptions in the visible region assigned to a combination of intra-ligand and metal-to-ligand charge-transfer. Heteroleptic [Cu(5)(Lancillary)]+ dyes in which 5 is the anchoring ligand ((6,6′-dimethyl-[2,2′-bipyridine]-4,4′-diyl)bis(4,1-phenylene))bis(phosphonic acid) and Lancillary = 1–4 have been assembled on fluorine-doped tin oxide (FTO)-TiO2 electrodes in dye-sensitized solar cells (DSCs). Performance parameters and external quantum efficiency (EQE) spectra of the DSCs (four fully-masked cells for each dye) reveal that the best performing dyes are [Cu(5)(1)]+ and [Cu(5)(3)]+. The alkynyl spacers are not beneficial, leading to a decrease in the short-circuit current density (JSC), confirmed by lower values of EQEmax. Addition of a co-absorbent (n-decylphosphonic acid) to [Cu(5)(1)]+ lead to no significant enhancement of performance for DSCs sensitized with [Cu(5)(1)]+. Electrochemical impedance spectroscopy (EIS) has been used to investigate the interfaces in DSCs; the analysis shows that more favourable electron injection into TiO2 is observed for sensitizers without the alkynyl spacer and confirms higher JSC values for [Cu(5)(1)]+.

In the transition from linear production systems, unsustainable from the point of view of resources, to a model that finds strength in environmental, social and economic sustainability, the circular economy paradigm is the foundation that facilitates the planetary agro-ecological transition. The European Union has taken a number of steps (including the Circular Economy Package of Directives) shaping circularity as a wide-ranging driver measure involving many sectors. The paper intends to provide a regulatory framework on the current general situation regarding circularity in European Union, in order to extrapolate and give evidence to the aspects that intersect the agri-food sector. This is not only because they are poorly addressed in the literature, but also because there is a lack of regulatory instruments on the circular economy specifically addressing this area of interest. For this purpose, the analysis focuses on waste and residue/scrap management issues, recognized by law as by-products and end-of-waste status, as they are covered by circular economy legislation and as they can be applied to the agri-food sector. The latter allow the implementation of circularity strategies in the agri-food sector and, given the numerousness of production chains and the peculiarities of each of them, various regeneration and/or reuse processes of specific resources may be depicted. The intent is to provide useful knowledge on how to implement sustainable waste management, also proposing a concrete case on a by-product of olive oil processing, through which it is possible to highlight how the correct application of regulations favors the adoption of circular economic and management models in the firms involved, as well as informing the relevant economic operators on the possible profiles of legal liability that may arise from insufficient knowledge. Furthermore, this paper delves into the European Green Deal’s Strategy as it enriches the circular economy paradigm with new facets. NextGenerationEU and the National Recovery and Resilience Plan financially support this strategy in the aftermath of the socioeconomic crisis from COVID-19 in the EU Member States. This is in order to achieve the objective of achieving the agro-ecological transition.

Este estudio evaluó los determinantes de la elección de estrategias indígenas relacionadas con el clima por parte de pequeños agricultores en el norte de Ghana utilizando datos primarios obtenidos a través de discusiones de grupos focales comunitarios y encuestas de hogares, y sujetos al modelo de regresión Multinomial Logit. Los resultados empíricos revelan que la presencia de un mercado, el crédito informal de amigos y familiares, la ubicación del agricultor, la extensión de agricultor a agricultor, notar una disminución de las precipitaciones y notar un aumento de la temperatura influyen en la elección de las estrategias indígenas relacionadas con el clima. Por lo tanto, existe la necesidad de mejorar el acceso de los pequeños agricultores al mercado, los servicios de extensión agrícola y su conocimiento de los cambios en las precipitaciones y la temperatura. Cette étude a évalué les déterminants du choix des stratégies autochtones liées au climat par les petits exploitants agricoles du nord du Ghana à l'aide de données primaires obtenues lors de groupes de discussion communautaires et d'enquêtes auprès des ménages, et soumises au modèle de régression Multinomial Logit. Les résultats empiriques révèlent que la présence d'un marché, le crédit informel d'amis et de parents, l'emplacement de l'agriculteur, l'extension de l'agriculteur à l'agriculteur, la constatation d'une diminution des précipitations et d'une augmentation de la température influencent le choix des stratégies autochtones liées au climat. Il est donc nécessaire d'améliorer l'accès des petits agriculteurs au marché, aux services de vulgarisation agricole et leur sensibilisation aux changements de précipitations et de température. This study assessed the determinants of Choice of Indigenous Climate Related Strategies by Smallholder Farmers in Northern Ghana using primary data obtained through community focus group discussions and household survey, and subjected to the Multinomial Logit regression model. The empirical results reveal that presence of a market, informal credit from friends and relatives, location of farmer, farmer-to-farmer extension, noticing of a decrease in rainfall and noticing an increase in temperature influence the choice of indigenous climate related strategies. There is therefore the need to improve smallholder farmers' access to market, agricultural extension services and their awareness of changes in rainfall and temperature. قيمت هذه الدراسة محددات اختيار الاستراتيجيات المتعلقة بالمناخ للسكان الأصليين من قبل المزارعين أصحاب الحيازات الصغيرة في شمال غانا باستخدام البيانات الأولية التي تم الحصول عليها من خلال مناقشات مجموعات التركيز المجتمعية والمسح الأسري، وتخضع لنموذج انحدار اللوغاريتم متعدد الحدود. تكشف النتائج التجريبية أن وجود سوق، والائتمان غير الرسمي من الأصدقاء والأقارب، وموقع المزارع، والإرشاد من مزارع إلى مزارع، وملاحظة انخفاض في هطول الأمطار وملاحظة زيادة في درجة الحرارة يؤثر على اختيار الاستراتيجيات المتعلقة بالمناخ المحلي. لذلك هناك حاجة إلى تحسين وصول صغار المزارعين إلى الأسواق وخدمات الإرشاد الزراعي ووعيهم بالتغيرات في هطول الأمطار ودرجة الحرارة.

This work has been published in Solar Energy Materials & Solar Cells 215 (2020) 110603 (DOI: 10.1016/j.solmat.2020.110603). Antimony selenide (Sb2Se3) based solar cell technology has experienced rapid development with demonstrated cell efficiency reaching ̴ 9.2% for devices with substrate configuration, hence necessitating more intense research investigation for further progress. Though the effect of crystallographic orientation in this non-cubic material on device performance is now well understood, the influence of composition and intrinsic defects remains debatable. In this work we describe the fabrication and device characteristics of Sb2Se3 solar cells designed in the substrate configuration of (SLG/Mo/Sb2Se3/CdS/i-ZnO+ITO). Notably, Sb2Se3 absorber layers with predominant (hk0) orientation were deposited in a single step by e-beam evaporation of pre synthesized bulk source material. As grown precursor Sb2Se3 thin films were subjected to reactive thermal annealing (RTA) treatment in the presence of Se source at different temperatures for enhancing their crystalline quality and balancing their stoichiometry. Analysis of the completed solar cells indicated improved efficiencies post RTA process, with the best performing devices exhibiting a power conversion efficiency (η) of ~ 4.34% for an absorber annealed at a temperature of 350 °C. The improved efficiency is ascribed to the observed changes in chemical composition of the absorber layer and the possible formation of related beneficial antisite defects. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 712949 (TECNIOspring PLUS)" and the Government of Catalonia's Agency for Business Competitiveness(ACCIÓ). This research was also supported by the Spanish Ministry of Science, Innovation and Universities under the WINCOST (ENE2016-80788-C5-1-R) project, and by the European Regional Development Funds (ERDF, FEDER Programa Competitivitat de Catalunya 2007-2013). Authors from IREC and the University of Barcelona belong to the SEMS (Solar Energy and Materials Systems) Consolidated Research Group of the 'Generalitat de Catalunya' (Ref. 2017 SGR 862). Ministry of New and Renewable Energy (MNRE) is very well acknowledged for funding the research activities at SRM IST through the project "Development of Lithium Ion Batteries and Computational Studies for Solar Absorber Layers, (Grant No. 31/03/2014-15/PVSE-R&D).

Diseño y evaluación de los servicios eléctricos para un hogar energéticamente eficiente: Nigeria se enfrenta a una grave escasez de electricidad Conception et évaluation des services électriques pour une maison écoénergétique - Le Nigeria est confronté à une grave pénurie d' électricité Design and evaluation of electrical services for an energy efficient home - Nigeria is facing an acute shortage of electric تصميم وتقييم الخدمات الكهربائية لمنزل موفر للطاقة - تواجه نيجيريا نقصًا حادًا في الكهرباء

Supercapacitors are common devices in electrical circuits that produce electrical pulses at high power levels in short periods of time. Electrodes for supercapacitors were prepared with activated carbon. Activated carbon was obtained from cassava peels treated by chemical activation with potassium hydroxide (KOH) and phosphoric acid (H3PO4), each at two different concentrations and at one carbonization temperature. Electrochemical performance of the prepared electrodes was obtained by means of cyclic voltammetry and galvanostatic charge-discharge in a 3-electrode system with an electrolytic solution of sulfuric acid (H2SO4) 1 M. Cyclic voltammetry allowed to indentify a behavior of supercapacitors in a potential window of -0.4V to 0.6V. Activated carbon derived from cassava peel with the highest specific surface area (398.46 m2/g) has exhibited the maximum specific capacitance of 64.18 F/g.

Renewable energies will represent an increasing share of the electricity supply, while flue and gasification-derived gases can be a promising CO2 feedstock with a heat load. In this study, microbial electrosynthesis of organic compounds from CO2 at high temperature was proposed as an alternative for valorising energy surplus and decarbonizing the economy. The unremitting fluctuation of renewable energy sources was assessed using two bioreactors at 50 °C, under circumstances of continuous and intermittent power supply (ON-OFF; 8-16 h), simulating an off-grid photovoltaic system. Results highlighted that maximum acetate production rate (43.27 g m-2 d-1) and columbic efficiency (98%) were achieved by working with an intermittent energy supply, while current density was reduced three times. This boosted the production of acetate per unit of electricity provided up to 138 g kWh-1 and reinforced the robustness of the technology by showing resilience to tolerate perturbations and returning to its initial state.