Energy efficiency and waste reuse: A solution for sustainability in poor West African countries? Case study of the shea butter supply chain in Burkina Faso

National audienceIn West African countries, the objective of producer insertion in competitive markets is often associated with the need to modernize and mechanize production processes, i.e., replace labour by machines. This excludes traditional producers who can barely comply with the economic criteria but who must remain competitive to generate higher incomes. The challenge is to improve the efficiency of traditional methods in supply chains rather than imposing modern technologies that producers hardly adopt. Moreover, West African populations suffer from not having cheap and available energy sources. They, therefore, have to be imaginative for more efficient energy use in order to improve the productivity and quality of their products and support sustainable rural development and incomes. Building on the case study of the shea butter supply chain in Burkina Faso, this article proposes an original approach consisting of improved energy use for a more competitive and sustainable activity. The traditional butter production process consumes a great deal of energy from firewood and generates a lot of organic waste that could be used as an energy source. We examined the feasibility of using alternative energy techniques that could be taken on board as they are simple and designed from local resources, whilst using by-products from the shea butter production chain as biofuels to partially replace firewood. We showed that using alternative energy techniques, taken one by one or combined, can lead to lower energy use and thereby increase women's incomes, whilst helping to conserve forests

Role of Hydroxyl Groups in the Basic Reactivity of MgO: a Theoretical and Experimental Study

Clean (i.e., carbonate- and hydroxyl-free) and hydroxylated MgO surfaces of various morphologies were used to study the correlation between thermodynamic Brønsted basicity (evaluated by the deprotonation of methanol and propyne followed by FTIR) and basic reactivity (evaluated by the conversion of 2-methyl-but-3-yn-2-ol (MBOH)). A correlation is evidenced for clean surfaces, but for hydroxylated surfaces, OH groups, though weak Brønsted bases, are much more active than oxide O2- ions. Some of the hydroxyl groups whose VOH infra-red stretching band is included in the narrow high-frequency OH band were shown to be responsible for such activity. In order to identify them, the irregularities of surfaces involving low coordination (LC) ions were modeled by DFT calculations (mono- and di-atomic steps for 4C ions, corners, kinks and divacancies for 3C ions). All of them dissociate water: except for kinks and divancancies where the OH formed can be considered as isolated, in all the other cases, OH groups are H-bonded. The í OH infra-red frequencies obtained by calculations are consistent with the experimental spectrum which exhibits two domains: the broad low-frequency (${\rm V}_{\rm OH} 3700$ cm-1) corresponds to isolated OH (O2CH, O3CH and O4CH in kinks and divacancies) and H-bond acceptor OH groups (O1CH and O2CH). The latter are inferred to be implied in basic reactivity of hydroxylated surfaces toward MBOH

Une économie solidaire peut-elle être féministe ?

Partout dans le monde, des femmes et des hommes se mobilisent pour faire de l’économie autrement, une économie citoyenne qui ne soit pas au service du profit mais de l'intérêt collectif, et fondée sur la solidarité. L'économie solidaire concerne-t-elle un secteur de seconde zone, tout juste bon à panser les plaies de l’économie néolibérale ou pallier les manques d’un service public déliquescent ou inexistant ? Comment expliquer le faible intérêt, dans la littérature sur l'économie sociale et solidaire, pour le genre et les théories féministes ? Pourtant, ces initiatives sont fortement genrées et les femmes y sont souvent surreprésentées. Les activités sont marquées par des valeurs implicites de don de soi ou de sacrifice pour le bien- être de la famille, face à la crise et aux déficiences des systèmes de protection sociale. À quelles conditions trouve-t-on dans ces initiatives une opportunité de réinvention de l'économie, réencastrée dans le social et le politique et au service de la justice sociale et de genre ? Quelles sont les alternatives face à la crise de la reproduction sociale ? Peut-on repenser le politique et la démocratisation de l'économie ? L'économie solidaire peut-elle constituer une source d'émancipation pour les femmes ou est-ce que la solidarité, souvent dans des situations d'exclusion, ne fait que reproduire les mécanismes de leur propre exploitation ? Dans quelle mesure et à quelles conditions l'économie solidaire peut-elle être féministe

Role of Hydroxyl Groups in the Basic Reactivity of MgO : a Theoretical and Experimental Study

International audienceClean (i.e., carbonate- and hydroxyl-free) and hydroxylated MgO surfaces of various morphologies were used to study the correlation between thermodynamic Brønsted basicity (evaluated by the deprotonation of methanol and propyne followed by FTIR) and basic reactivity (evaluated by the conversion of 2-methyl-but-3-yn-2-ol (MBOH)). A correlation is evidenced for clean surfaces, but for hydroxylated surfaces, OH groups, though weak Brønsted bases, are much more active than oxide O2- ions. Some of the hydroxyl groups whose VOH infra-red stretching band is included in the narrow high-frequency OH band were shown to be responsible for such activity. In order to identify them, the irregularities of surfaces involving low coordination (LC) ions were modeled by DFT calculations (mono- and di-atomic steps for 4C ions, corners, kinks and divacancies for 3C ions). All of them dissociate water: except for kinks and divancancies where the OH formed can be considered as isolated, in all the other cases, OH groups are H-bonded. The í OH infra-red frequencies obtained by calculations are consistent with the experimental spectrum which exhibits two domains: the broad low-frequency (${\rm V}_{\rm OH} 3700$ cm-1) corresponds to isolated OH (O2CH, O3CH and O4CH in kinks and divacancies) and H-bond acceptor OH groups (O1CH and O2CH). The latter are inferred to be implied in basic reactivity of hydroxylated surfaces toward MBOH