Africa is the most affected continent with energy poverty. Wood fuel is the main source of energy for remote and rural populations. At the same time, most parts of Africa are endowed with abundant solar energy. Togeth...Africa is the most affected continent with energy poverty. Wood fuel is the main source of energy for remote and rural populations. At the same time, most parts of Africa are endowed with abundant solar energy. Together with a highly developed global solar industry and ever declining cost of solar systems, solar has unprecedented potential to combat energy poverty in Africa. However, dissemination of solar systems is faced with a number of barriers and challenges amongst where sustainable financing and lack of technological support for installation, maintenance and repair of systems are the most significant. This paper discusses the cases of Botswana and Namibia where financing schemes based on different partnership models have been successfully implemented. These schemes have the potential for success and adaptation by countries with similar socio-economic conditions. We conclude with recommendations on training programs for different levels of intervention to overcome the lack of technological support.展开更多
BaFe10A12O19/poly（m-toluidine） （BFA/PMT） composites were synthesized by in-situ polymerization of m-toluidine in the presence of BaFe10Al2O19 particles. The structure, composition and morphology of the obtained sa...BaFe10A12O19/poly（m-toluidine） （BFA/PMT） composites were synthesized by in-situ polymerization of m-toluidine in the presence of BaFe10Al2O19 particles. The structure, composition and morphology of the obtained samples were characterized by using XRD, FT-IR, UV-visible spectroscopy, SEM and TEM techniques. Their electrical conductivity, magnetic property and microwave absorbing property were measured by the four-probe meter, the vibrating sample magnetometer and the vector network analyzer, respectively. The results indicated that BFA particles were coated effectively by PMT polymer and some interactions between PMT and BFA particles existing in the composites. The conductivity of BFA/PMT composite is smaller than that of pure polymers and its saturation magnetization is a little smaller than that of pure BFA. The influence of the constitution and film thickness of absorbent on its microwave absorbing property is evident. The microwave absorbing properties of the BFA/PMT composites are better than those of pure BFA and PMT. When optimizing the mass rate of BFA/PMT to 0.3, the absorbent with 2 mm film thickness has the minimum reflection loss of -28.26 dB at approximate 14.24 GHz, and the maximum available bandwidth of 8.8 GHz, respectively. The results show that these composites can be used as advancing absorption and shielding materials due to their favorable microwave absorbing property.展开更多
文摘Africa is the most affected continent with energy poverty. Wood fuel is the main source of energy for remote and rural populations. At the same time, most parts of Africa are endowed with abundant solar energy. Together with a highly developed global solar industry and ever declining cost of solar systems, solar has unprecedented potential to combat energy poverty in Africa. However, dissemination of solar systems is faced with a number of barriers and challenges amongst where sustainable financing and lack of technological support for installation, maintenance and repair of systems are the most significant. This paper discusses the cases of Botswana and Namibia where financing schemes based on different partnership models have been successfully implemented. These schemes have the potential for success and adaptation by countries with similar socio-economic conditions. We conclude with recommendations on training programs for different levels of intervention to overcome the lack of technological support.
基金supported by the National Nature Science Foundation of China (21071125)the Natural Science Foundation of Zhejiang Province(Y4100022,Y4090636)the Science and Technology Key Project of Zhejiang Province (2010C11053)
文摘BaFe10A12O19/poly（m-toluidine） （BFA/PMT） composites were synthesized by in-situ polymerization of m-toluidine in the presence of BaFe10Al2O19 particles. The structure, composition and morphology of the obtained samples were characterized by using XRD, FT-IR, UV-visible spectroscopy, SEM and TEM techniques. Their electrical conductivity, magnetic property and microwave absorbing property were measured by the four-probe meter, the vibrating sample magnetometer and the vector network analyzer, respectively. The results indicated that BFA particles were coated effectively by PMT polymer and some interactions between PMT and BFA particles existing in the composites. The conductivity of BFA/PMT composite is smaller than that of pure polymers and its saturation magnetization is a little smaller than that of pure BFA. The influence of the constitution and film thickness of absorbent on its microwave absorbing property is evident. The microwave absorbing properties of the BFA/PMT composites are better than those of pure BFA and PMT. When optimizing the mass rate of BFA/PMT to 0.3, the absorbent with 2 mm film thickness has the minimum reflection loss of -28.26 dB at approximate 14.24 GHz, and the maximum available bandwidth of 8.8 GHz, respectively. The results show that these composites can be used as advancing absorption and shielding materials due to their favorable microwave absorbing property.
