A spasm is a sudden, involuntary contraction of a muscle, a group of muscles, or a hollow organ such as a heart, or a similarly sudden contraction of an orifice.It most commonly refers to a muscle cramp which is often accompanied by a sudden burst of pain, but is usually harmless and ceases after a few minutes. spasm is a sudden, involuntary contraction of a muscle, a group of muscles, or a hollow organ such as a heart, or a similarly sudden contraction of an orifice.
Top 10 largest Cement Producing Countries in the World. China has the first stage in the list of cement producing countries. They produce more than 2482 million tonnes. It is mainly used for construction and china is highly populated.
Holcim, the third largest global cement producer of 2013, self-reported a cement production capacity of 218Mt/yr via its website, compared with 174Mt/yr from the Global Cement Directory 2013, and 217Mt/yr in the Top 20 global cement companies of 2012.