Enhanced thermoelectric performance of a chalcopyrite compound CuIn3Se5-xTex (x=0~0.5) through crystal structure engineering

In this work the chalcopyrite CuIn3Se5−xTex (x = 0~0.5) with space group through isoelectronic substitution of Te for Se have been prepared, and the crystal structure dilation has been observed with increasing Te content. This substitution allows the anion position displacement ∆u = 0.25-u to be zero at x ≈ 0.15. However, the material at x = 0.1 (∆u = 0.15 × 10−3), which is the critical Te content, presents the best thermoelectric (TE) performance with dimensionless figure of merit ZT = 0.4 at 930 K. As x value increases from 0.1, the quality factor B, which informs about how large a ZT can be expected for any given material, decreases, and the TE performance degrades gradually due to the reduction in nH and enhancement in κL. Combining with the ZTs from several chalcopyrite compounds, it is believable that the best thermoelectric performance can be achieved at a certain ∆u value (∆u ≠ 0) for a specific space group if their crystal structures can be engineered

Can international health programmes be sustained after the end of international funding? The case of eye care interventions in Ghana

There is general agreement amongst major international policy makers that sustainability is a key component of health interventions in developing countries. However, there is little evidence on the factors enabling or constraining sustainability. Diffusion of innovation theory can help explain how the continuation of activities is related to the attributes of innovations. Innovations are characterised by five attributes: (i) relative advantage; (ii) compatibility; (iii) complexity; (iv) triability; and (v) observability. An eye care programme was selected as a case study. The programme was implemented in the Brong Ahafo region of Ghana and had been funded over a ten-year period by an international organisation

Study of LAS behaviour in sewage using advanced UV spectrophotometry

International audienceLinear alkylbenzenesulphonate( LAS) determination can be an important factor in the control of waste water discharges into natural environment. As it is the main anionic surfactant continuously used world wide it can be used as an indicator of detergents in water. The purpose of this work is the study of LAS behaviour in sewage using directUV absorption spectra deconvolution. This method is applied in order to observe LAS distribution and degradation during biological and physico-chemical sewage treatment up to the discharge into rivers and to assess the effects of sample preservation or pretreatmenton its determinatio

Simple LAS determination in sewage using advanced UV spectrophotometry

International audienc

Logistique de performance dans le transport routier de marchandises : une approche par filière productive,

rapport pour le groupement régional de recherches sur les transport