In the most general sense of the word, a cement is a binder, a substance which sets and hardens independently, and can bind other materials together. The word "cement" traces to the Romans Ancient Rome was a civilization that grew out of a small agricultural community founded on the Italian Peninsula as early as the 10th century BC. Located along the Mediterranean Sea, it became one of the largest empires in the ancient world, who used the term "opus caementicium" to describe masonry which resembled concrete and was made from crushed rock with burnt lime Calcium oxide , commonly known as burnt lime, lime or quicklime, is a widely used chemical compound. It is a white, caustic and alkaline crystalline solid at room temperature. As a commercial product, lime often also contains magnesium oxide, silicon oxide and smaller amounts of aluminium oxide and iron oxide. The name lime (native lime) refers to as binder. The volcanic ash and pulverized brick additives which were added to the burnt lime to obtain a hydraulic binder were later referred to as cementum, cimentum, cäment and cement. Cements used in construction are characterized as hydraulic or non-hydraulic.

The most important use of cement is the production of mortar Mortar is a workable paste used to bind construction blocks together and fill the gaps between them. The blocks may be stone, brick, cinder blocks, etc. Mortar becomes hard when it sets, resulting in a rigid aggregate structure. Modern mortars are typically made from a mixture of sand, a binder such as cement or lime, and water. Mortar can also be and concrete Concrete is a construction material composed of cement as well as other cementitious materials such as fly ash and slag cement, aggregate (generally a coarse aggregate such as gravel, limestone, or granite, plus a fine aggregate such as sand), water, and chemical admixtures. The word concrete comes from the Latin word "concretus" (—the bonding of natural or artificial aggregates to form a strong building material which is durable in the face of normal environmental effects.

Concrete Concrete is a construction material composed of cement as well as other cementitious materials such as fly ash and slag cement, aggregate (generally a coarse aggregate such as gravel, limestone, or granite, plus a fine aggregate such as sand), water, and chemical admixtures. The word concrete comes from the Latin word "concretus" ( should not be confused with cement because the term cement refers only to the dry powder substance used to bind the aggregate materials of concrete. Upon the addition of water and/or additives the cement mixture is referred to as concrete, especially if aggregates have been added.

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N.Korea's Currency Reform 'a Bid to Cement Power' - The Chosun Ilbo
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N.Korea's Currency Reform 'a Bid to Cement Power'

The Chosun Ilbo

The biggest motivation behind North Korea's sudden currency reform Tuesday appears to be Kim Jong-il's intention to throttle the emerging free market, ...



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