A collecting expedition has been carried out in the central part of Calabria region, south Italy; it has been concentrated on Reventino, Serre, Occitan and Albanian areas that were covered in certain coinciding sites ...A collecting expedition has been carried out in the central part of Calabria region, south Italy; it has been concentrated on Reventino, Serre, Occitan and Albanian areas that were covered in certain coinciding sites in the past. In totality, 50 accessions belonging to 14 taxa were collected from 8 collecting sites, representing mainly highly variable old landraces of vegetables and cereals and, especially, of pulses; most of them that appear severely threatened by genetic erosion are still cultivated, at certain level, by old farmers and directly used by their families. A comparison of the results of the previous missions that have been carried out in Calabria region that preserve valuable crop genetic resources on farm shows the large degree of genetic erosion for all crops collected. The results stressed the need to conserve a considerable amount of material endangered and the necessity of our ongoing care for their preservation either on farms or ex situ in genebanks. The complementarity of both conservation methods is needed.展开更多
The modelling and optimization for the alkaline sulphide leaching of a complex copper concentrate containing 1.69% Sb and 0.14% Sn were studied.Response surface methodology,in combination with central composite face-c...The modelling and optimization for the alkaline sulphide leaching of a complex copper concentrate containing 1.69% Sb and 0.14% Sn were studied.Response surface methodology,in combination with central composite face-centred design(RSM-CCF),was used to optimise the operating parameters.The leaching temperature,sulphide ion concentration and solid concentration were chosen as the variables,and the response parameters were antimony and tin recovery,and the time required to achieve 90% Sb dissolution.It was confirmed that the leaching process was strongly dependent on the reaction temperature as well as the sulphide ion concentration without any significant dependence on the solid concentration.Furthermore,a mathematical model was constructed to characterise the leaching behaviour.The results from the model allow identification of the most favourable leaching conditions.The model was validated experimentally,and the results show that the model is reliable and accurate in predicting the leaching process.展开更多
文摘A collecting expedition has been carried out in the central part of Calabria region, south Italy; it has been concentrated on Reventino, Serre, Occitan and Albanian areas that were covered in certain coinciding sites in the past. In totality, 50 accessions belonging to 14 taxa were collected from 8 collecting sites, representing mainly highly variable old landraces of vegetables and cereals and, especially, of pulses; most of them that appear severely threatened by genetic erosion are still cultivated, at certain level, by old farmers and directly used by their families. A comparison of the results of the previous missions that have been carried out in Calabria region that preserve valuable crop genetic resources on farm shows the large degree of genetic erosion for all crops collected. The results stressed the need to conserve a considerable amount of material endangered and the necessity of our ongoing care for their preservation either on farms or ex situ in genebanks. The complementarity of both conservation methods is needed.
文摘The modelling and optimization for the alkaline sulphide leaching of a complex copper concentrate containing 1.69% Sb and 0.14% Sn were studied.Response surface methodology,in combination with central composite face-centred design(RSM-CCF),was used to optimise the operating parameters.The leaching temperature,sulphide ion concentration and solid concentration were chosen as the variables,and the response parameters were antimony and tin recovery,and the time required to achieve 90% Sb dissolution.It was confirmed that the leaching process was strongly dependent on the reaction temperature as well as the sulphide ion concentration without any significant dependence on the solid concentration.Furthermore,a mathematical model was constructed to characterise the leaching behaviour.The results from the model allow identification of the most favourable leaching conditions.The model was validated experimentally,and the results show that the model is reliable and accurate in predicting the leaching process.