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Purpose: Dyeing and printing are important steps in textile manufacturing. After the process completion, these dyes are released in the effluent. These dyes impart an unacceptable appearance but are also toxic to the soil and water bodies. The present research has been carried out to study the rate of photocatalytic degradation of an azo dye, namely, CI Direct Green 26, using titania nanoparticles under ultra violet (UV) irradiation as a function of temperature and time. Azo dyes account for the majority of all dyestuffs are produced and extensively used in the textile, paper, food, leather, cosmetics and pharmaceutical industries. Titania nanoparticles have been found to successfully degrade these dyes in the presence of UV light. The purpose of the present paper was to study the photodegradation of azo dyes using titania nanoparticles at different temperatures and time periods. Design/methodology/approach: Titania nanoparticle concentration of 0.1% (w/v) was dispersed in distilled water by sonication for 1 h in sonication bath. The of rate of degradation of Direct Green 26 dye in the titania nanoparticle dispersion, under UV-A exposure was studied at different temperatures ranging from 25°C to 65 °C for time periods ranging from 1 h to 6 h. Photocatalytic degradation tests were performed in a specially designed UV reactor chamber. Raman spectroscopy of Titania nanoparticles, dye and titania/dye mixture before and after UV exposure was carried out using Confocal Laser Dispersion Raman Microscope (Renishaw, UK) with 785 nm excitation laser. Findings: Titanium dioxide is an efficient photocatalyst for decolourisation of direct dye. The photodegradation of the direct Green dye was found to follow the pseudo first-order reaction. The Arrhenius activation energy was found to be 24.8 kJ/mol with A value of 0.0013 for the photocatalytic degradation of the dye. Raman spectroscopy also confirmed the adsorption of dye on titania nanoparticle and its complete degradation on exposure to UV light. Practical implications: This research highlights the application of titania nanoparticles for the effective degradation of dye in the effluent from textiles, clothing, paper and any kind of dyeing process. Azo dyes account for the majority of all dyestuffs are produced and extensively used in the textile, paper, food, leather, cosmetics and pharmaceutical industries. Titania nanoparticles have been found to successfully degrade these dyes in the presence of UV light which can be very beneficial for the effluent treatment plants in textile and other industries. Originality/value: Azo dyes are one of the harmful pollutants released in textile waste water. The degradation and removal of the coloured waste in the textile effluent is an important environmental concern and needs to be investigated. The research is one of the first to investigate and understand the mechanism of the degradation of an azo dye in the presence of titania nanoparticles by Raman spectroscopy. [ABSTRACT FROM AUTHOR]

Pedestrian crossing warrants are guidelines used around the world for safe pedestrian crossing movements. Pedestrian volume (P) and vehicular volume (V) are the most widely used parameters in crossing warrants. PV2-based pedestrian crossing warrants are used in India, Iran, and UK. These warrants were first reported in UK in 1987 and adopted in India in 1988. The registered vehicles in India have increased 10 times since then. Moreover, the pedestrian crossing warrants recommended in India by IRC 103:2012 do not identify the type of crossing facility to be installed in case, the warrant criteria is satisfied. To re-examine the existing warrants, the maximum hourly pedestrian and vehicular flows estimated from the data are used as the upper bounds for developing the PV2 matrices. K-means clustering was used to obtain the new PV2 threshold values. The proposed warrant charts can be used to identify the type of crossing facility that is suitable for a location based on the observed peak hour pedestrian and vehicular volume. [ABSTRACT FROM AUTHOR]

Non-ordinary experience forms the essence of tourism phenomenon. For western tourists non-ordinary settings of excellence are provided by Oriental cultures, which are markedly different from their own culture. Thus the western culture with its obsession for efficiency and emphasis on material consumption may influence, humiliate or even absorb the local culture. The global economic significance of tourism and the fact that tourism is developing fast and constantly to new places has made tourism a highly socio-cultural and a political activity. Whether globalization will succeed and consequently lead to the disintegration of local identity of a tourist destination depends on how tourism and its global connections can create well-being. Keeping the above idea in mind an International Symposium was organized by the University of Brighton, Eastbourne, Great Britain during September11-12, 2003. The conference included keynote addresses that were presented by distinguished tourism scholars from all over the world.