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Ultraviolet Light

( Article Type: Explanation )

Ultraviolet (UV) radiation is between visible light and X-rays on the spectrum (4 x 10-7 to 5 x 10-9). The UV spectrum is further divided by wavelengths into A, B and C bands.

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Urban Agriculture

( Article Type: Explanation )

Cities and towns are not the places where one would usually think that agriculture should be undertaken, but urban agriculture can be a valuable contribution to the development of sustainable cities.

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Urban Greening

( Article Type: Explanation )

Urban greening describes the varied initiatives that are being undertaken within the urban areas to ‘green’ and soften the urban landscape and make it more ‘people friendly’.

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( Article Type: Explanation )

The term ‘Urbanisation’ describes the growing trend of populations to gravitate toward living in city or urban environments. The towns and cities of the world are growing at ever increasing rates.

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Used Oil

( Article Type: Explanation )

In South Africa, about 82 million litres of used oil is collected per annum. Unless recovered, this used oil poses a serious hazard to the environment and to the country's groundwater resources in particular.

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