1000 resultados para photo-switchable


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Panoramic View showing all three campusses.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Publication suspended, July 1932-May 1936

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Thesis (doctoral)--Kgl. Technische Hochschule Munchen.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Title from cover.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Discoloration and mineralization of Reactive Red HE-3B were studied by using a laponite clay-based Fe nanocomposite (Fe-Lap-RD) as a heterogeneous catalyst in the presence of H2O2 and UV light. Our experimental results clearly indicate that Fe-Lap-RD mainly consists of Fe2O3 (meghemite) and Fe2Si4O10(OH)2 (iron silicate hydroxide) which have tetragonal and monoclinic structures, respectively, and has a high specific surface area (472m(2) / g) as well as a high total pore volume (0.547 cm(3)/g). It was observed that discoloration of HE-3B undergoes a much faster kinetics than mineralization of HE-3B. It was also found that initial HE-3B concentration, H2O2 concentration, UV light wavelength and power, and Fe-Lap-RD catalyst loading are the four main factors that can significantly influence the mineralization of HE-3B. At optimal conditions, complete discoloration of 100 mg/L HE-3B can be achieved in 30 min and the total organic carbon removal ratio can attain 76% in 120 min, illustrating that Fe-Lap-RD has a high photo-catalytic activity in the photo-assisted discoloration and mineralization of HE-3B in the presence of UV light (254nm) and H2O2. (C) 2003 Elsevier Science Ltd. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A novel laponite RD clay-based Fe nanocomposite (Fe-Lap-RD) has been successfully synthesized through a reaction between a solution of iron salt and an aqueous dispersion of laponite RD clay. The X-ray diffraction (XRD) results reveal that the Fe-Lap-RD mainly consists of Fe2O3 (maghemite) and Fe2Si4O10(OH)2 (iron silicate hydroxide), which have tetragonal and monoclinic structures, respectively, and has a high specific surface area as well as a high pore volume. The photo-catalytic activity of the Fe-Lap-RD was examined in the photo-assisted degradation of an organic azo dye Orange II. It was found that the mineralization of Orange 11 undergoes a slower kinetics than discoloration, and 70% total organic carbon (TOC) of 0.2 mM Orange 11 can be removed in 90 min, implying that the Fe-Lap-RD exhibited a high photo-catalytic activity in the presence of H2O2 and UV light (254 nm) in the photo-assisted degradation of Orange II. In addition, our experiments also illustrate that the Fe-Lap-RD has a long-term stability but is of low cost. This study illustrates the possibility of photo-assisted degradation of organic compounds without the requirements to remove the Fe ions after reaction. Two possible catalytic reaction mechanisms are also proposed. (C) 2003 Elsevier Science Ltd. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The phenology of 11 diverse accessions of wild mungbean was observed under natural and artificial photoperiod - temperature conditions, in order to examine whether genotypic differences might be attributed to adaptive responses to photo-thermal conditions. There was large variation in phenological response among accessions and across environments, much of which was due to differences in the duration of the pre-flowering phase. Accessions that flowered earlier tended to flower for longer, apart from 2 earlier flowering, inland Australian lines that were also earlier maturing. The patterns of response in time from sowing to flowering over environment were consistent with quantitative short-day photoperiodic adaptation, a conclusion supported by the effects of artificial day-length extension and by 'goodness of fit' of the observed responses to standard models relating rate of development to photoperiod and temperature. The fitted models indicated that rate of development towards flowering was hastened by warmer temperatures, and delayed by longer day lengths, with differential sensitivity between accessions to both factors. The models also suggested that photoperiod was more important for accessions collected closer to the equator, which were generally later flowering as a consequence. Conversely, temperature was relatively more important in lines from higher latitudes. Modelling also suggested that the period from first flowering to maturity was sensitive to photoperiod and temperature. Again, longer days appeared to prolong growth and delay maturity. However, cooler temperatures accelerated rather than slowed maturity, by suppressing further vegetative growth. The variation observed indicated that there is considerable scope for using the wild population to broaden the adaptation of cultivated mungbean. In particular, the unusual response of a late-flowering, photoperiod-insensitive accession warrants further study to establish whether the wild population contains a unique 'long juvenile' trait analogous to that being used for improving phenological adaptation in soybean.