Synthesis of fluorescence poly(N-vinylpyrrolidone) via click chemistry using azide-terminated xanthate mediator (S)-2-(4-azidobutyl propionate)-(O-ethyl xanthate)

Azide-terminated xanthate RAFT agent (S)-2-(4-azidobutyl propionate)-(O-ethyl xanthate) has been synthesized and used for the controlled radical polymerization of N-vinylpyrrolidone (NVP). Kinetics study showed the pesudo first-order kinetics along with gradual increase in molecular weight (M_n) of the resulted polymer up to 69% conversion. Chain-end analysis of the resulted polymer by ¹H NMR showed the presence of the fragments of xanthate mediator at both chain ends. Successful chain extension has also been performed via the click reaction of alkyne-terminated PNVP with azide-terminated PNVP. Moreover, fluorescence pyrene-tagged PNVP has successfully been made via the click reaction of alkyne-functionalized pyrene with azide-terminated PNVP.     

Environmental and power generation implications of efficient electrical appliances for India

We analyse the potentials of selected efficient appliances (EAs) for air pollutant mitigation and reducing the need for rapidly escalating power generation in India from the national, utility and user perspectives. The study shows that about 10.1% of total cumulative generation and about 7.4, 8.7 and 9.8% of total cumulative CO₂, SO₂ and NO_x emissions, respectively, could be avoided between 1997 and 2015 by using EAs. At currently prevailing electricity and appliance prices, cost-effective levels of avoided generation and air pollutant mitigation potentials are significantly lower from the users' viewpoint. The level of air pollutant mitigation would be significantly higher if an efficient electricity pricing policy were adopted and if relatively low interest loans were available for the purchase of EAs.     

Factors affecting transport sector CO2 emissions growth in Latin American and Caribbean countries: An LMDI decomposition analysis

This study determines the factors responsible for the growth of transport sector CO₂ emissions in 20 Latin American and Caribbean (LAC) countries during the 1980–2005 period by decomposing the emissions growth into components associated with changes in fuel mix (FM), modal shift and economic growth, as well as changes in emission coefficients (EC) and transportation energy intensity (EI). The key finding of the study is that economic growth and the changes in transportation EI are the principal factors driving transport sector CO₂ emission growth in the countries considered. While economic growth is responsible for the increasing trend of transport sector CO₂ emissions in Argentina, Brazil, Costa Rica, Peru and Uruguay, the transportation EI effect is driving CO₂ emissions in Bolivia, the Caribbean, Cuba, Ecuador, Guatemala, Honduras, Other Latin America, Panama and Paraguay. Both economic activity (EA) and EI effects are found responsible for transport sector CO₂ emissions growth in the rest of the Latin American countries. In order to limit CO₂ emissions from the transportation sector in LAC countries, decoupling of the growth of CO₂ emissions from economic growth is necessary; this can be done through policy instruments to promote fuel switching, modal shifting and reductions in transport sector EI. Copyright © 2008 John Wiley & Sons, Ltd.     

Photodeposition of AuNPs on metal oxides: Study of SPR effect and photocatalytic activity

Effect of photodeposition of AuNPs (gold nanoparticles) on TiO₂, CeO₂, Cu₂O and Fe₃O₄ supports has been illustrated on sacrificial donor based hydrogen evolution. The synthesized samples were characterized by diffuse reflectance spectroscopy (DRS), and transmission electron microscopy (TEM). Highest photocatalytic activity was exhibited by Au/TiO₂ followed by Au/Fe₃O₄, Au/CeO₂ and Au/Cu₂O. Au/TiO₂ under optimized conditions has shown significantly high photocatalytic activity under both UV–visible and visible radiation. Au/TiO₂ shows hydrogen evolution rate of 920 μmol h⁻¹ and 32.4 μmol h⁻¹ under UV–visible and visible radiation, respectively. Significant enhancement in hydrogen evolution rate under visible light is very encouraging and may be attributed to polydispersed nature of AuNPs wherein larger particles facilitate light absorption and the smaller function as catalytic sites. Further studies are in progress to study the influence of various parameters on photocatalytic activity of Au/TiO_2.     

Photovoltaics literature survey (no. 78)

In order to help keep readers up‐to‐date in the field each issue of Progress in Photovoltaics will contain a list of recently published journal articles most relevant to its aims and scope. This list is drawn from an extremely wide range of journals, including IEEE Transactions on Electron Devices, Journal of Applied Physics, Applied Physics Letters, Progress in Photovoltaics and Solar Energy Materials and Solar Cells. To assist the reader, the list is separated into broad categories, but please note that these classifications are by no means strict. Also note that inclusion in the list is not an endorsement of a paper's quality. If you have any suggestions please email Santosh Shrestha at mailto: s.shrestha@unsw.edu.au .

     

Photovoltaics literature survey (No. 114)

In order to help keep readers up‐to‐date in the field each issue of Progress in Photovoltaics will contain a list of recently published journal articles most relevant to its aims and scope. This list is drawn from an extremely wide range of journals, including IEEE Transactions on Electron Devices, Journal of Applied Physics, Applied Physics Letters, Progress in Photovoltaics and Solar Energy Materials and Solar Cells. To assist the reader, the list is separated into broad categories, but please note that these classifications are by no means strict. Also note that inclusion in the list is not an endorsement of a paper's quality. If you have any suggestions please email Santosh Shrestha at s.shrestha@unsw.edu.au .