Region

Urban spheres of influence and rural urban fringe

Urban spheres of influence and rural urban fringe Urban spheres of influence Urban spheres of influence reflect centre-to-hinterland relationship, compared with the non-central region, the centre assumes more complex economic functions, and provides more economic activities. Famous theoretical contributions to this research field are the Central Place Theory (Christaller, 1933), the extension to the Central … Read more

Non Metals

Non Metals As far as elements are concerned, a nonmetal is simply an element that does not display the properties of a metal. It is not defined by what it is, but by what it is not. It doesn’t look metallic, can’t be drawn into a wire or pounded into shape or bent, doesn’t conduct … Read more

Properties of soaps and detergents

Properties of soaps and detergents Soap – Characteristics And Uses Soaps are excellent cleansing agents and have good biodegradability. A serious drawback which reduces their general use, is the tendency for the carboxylate ion to react with Ca+ and Mg+ ions in hard water. The result is a water insoluble salt which can be deposited on … Read more