Efficient photocatalytic activity in the visible range has been achieved with titanium oxide thin films. Doping, induced by oxygen deficiencies, is the key to the increased photodegradation ...properties of the film as both experimental and theoretical studies of the thin films demonstrate. The Figure shows an AFM image of the surface morphology of a TiO2 layer.
Anatase phase of titanium oxide is the most promising photocatalyst material for organic pollutant degradation. However, due to its large band gap energy (3.2
eV) it is not viable to use sunlight as ...an energy source for the photocatalysis activation, and so, ultraviolet (UV) radiation below the wavelength of 380
nm is required.
This paper focuses on the experimental demonstration of the reduction of this large band gap energy by inducing defects in the anatase structure under the form of oxygen sub-stoichiometry. TiO
2 thin films were prepared in a metal organic chemical vapour deposition (MOCVD) reactor. The samples stoichiometry was measured by the Rutherford backscattering spectrometry (RBS) technique. Optical characterisation was also performed and the photodegradation activity in the visible range was tested using nonylphenol, which is one of the most harmful pollutants present in waste waters.
Titanium thin films have been designed to achieve efficient photocatalytic activity in the visible range. Doping induced by oxygen deficiency is the key for the increased photodegradation properties ...of the film, as both experimental and theoretical studies demonstrate. Its effectiveness on a nonylphenol solution has been demonstrated.
Community mapping projects have been studied as important contributions to the field of environmental justice and Public Participation Geographic Information Systems (PPGIS). As a collaborative ...project between the Colectivo Salud y Justicia Ambiental and Red de Ciudadanos por el Mejoramiento de las Comunidades (RECIMEC), the "Mapeo Comunitario de la Zona Alamar" was created as a mechanism for community participation in the urban planning process in Tijuana, México. This paper outlines the project's community mapping process, including planning, data collection, priority identification, and data submission. Results from this community mapping project are analyzed including the (1) particular environmental risks and goods in this border region, (2) the influence that the project data had on the urban planning process, and (3) the impact that the community mapping process had on community organizing capacity. Our findings point to particular environmental challenges in this border city including clandestine trash dumps, and contaminated water runoff points. The mapping project influenced the land use planning process by identifying the key environmental risks and goods to prioritize in the zoning and ground truthing urban planning data. The community mapping project also had a key impact on community organizing through the fomenting of knowledge and relationships between community members and government representatives at the city's urban planning agency.
The anatase phase of TiO2 is the most promising photocatalyst for organic pollutants degradation. However, due to the large anatase band gap energy the possibility of using visible sunlight as energy ...source for the photocalatysis activation is ruled out and ultraviolet (UV) radiation with a wave length below the critical limit is thus required. Inducing defects in the anatase crystalline structure in the form of oxygen substoichiometry may theoretically reduce this large band gap energy.
This paper focuses on the determination of the stoichiometry of TiO2 thin films and its influence on the photodegradation properties.
By canvassing a range of international scientific disputes, including the EC-Biotech and EC-Hormones disputes in the WTO, the case concerning Pulp Mills and the Gabcíkovo–Nagymaros case in the ...International Court of Justice, and the Mox Plant and Land Reclamation cases dealt with under the United Nations Convention on the Law of the Sea, Caroline Foster examines how the precautionary principle can be accommodated within the rules about proof and evidence and advises on the boundary emerging between the roles of experts and tribunals. A new form of reassessment proceedings for use in exceptional cases is proposed. Breaking new ground, this book seeks to advance international adjudicatory practice by contextualising developments in the taking of expert evidence and analysing the justification of and potential techniques for a precautionary reversal of the burden of proof, as well as methods for dealing with important scientific discoveries subsequent to judgements and awards.
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