A cement is a binder, a substance that sets and hardens and can bind other materials together. The word "cement" can be traced back to the Roman term opus caementicium, used to describe masonry resembling modern concrete that was made from crushed rock with burnt lime as binder. The volcanic ash and pulverized brick supplements that 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 can be characterized as being either hydraulic or non-hydraulic, depending upon the ability of the cement to set in the presence of water (see hydraulic and non-hydraulic lime plaster).
Non-hydraulic cement will not set in wet conditions or underwater; rather, it sets as it dries and reacts with carbon dioxide in the air. It can be attacked by some aggressive chemicals after setting.
Hydraulic cements (e.g., Portland cement) set and become adhesive due to a chemical reaction between the dry ingredients and water. The chemical reaction results in mineral hydrates that are not very water-soluble and so are quite durable in water and safe from chemical attack. This allows setting in wet condition or underwater and further protects the hardened material from chemical attack. The chemical process for hydraulic cement found by ancient Romans used volcanic ash (activated aluminium silicates) with lime (calcium oxide).
Cement (Russian: Цемент) is a Russian novel by Fyodor Gladkov (1883–1958). Published in 1925, the book is arguably the first in Soviet Socialist Realist literature to depict the struggles of post-Revolutionary reconstruction in the Soviet Union.
The protagonist, Gleb Chumalov, is a returning Red Army soldier hero who after the Russian Civil War comes back to a hometown in painful transition and to its cement factory being reorganized for the massive new Soviet effort. His wife, Dasha, plays the role of the Soviet "new woman," and Gleb finds he cannot easily pick up the threads of their old relationship. The novel is Gladkov's best known work because of its portrayal of the sociological effects of early Communism, especially after the sexes are suddenly decreed equal in the labor force of the local cement factory.
A Red Soldier returns home from the war victorious, eager to return to his wife, comrades, and factory, only to find out that the Revolution is in shambles, and that the country is in famine despite food rations. When he left three years earlier, Revolution was in the air. Now his wife's heart has hardened, his comrades no longer recognize him, and the factory is deserted, stripped bare by the starving citizens. Nearly everyone has abandoned the Revolution, and icons of the revolution collect dust, neglected. Only a few have remained loyal to the Revolutionary ideals. These few serve as examples of the ideal socialist citizen, but there are too few of them and a socialist state requires the masses to operate the machine of the socialist cause.
Cement is a material for bonding stone or brick.
Cement may also refer to:
Crying is the shedding of tears in response to an emotional state. The act of crying has been defined as "a complex secretomotor phenomenon characterized by the shedding of tears from the lacrimal apparatus, without any irritation of the ocular structures". A related medical term is lacrimation, which also refers to non-emotional shedding of tears. Crying is also known as weeping, wailing, whimpering, and bawling.
For crying to be described as sobbing, it usually has to be accompanied by a set of other symptoms, such as slow but erratic inhalation, occasional instances of breath holding and muscular tremor.
A neuronal connection between the lacrimal gland (tear duct) and the areas of the human brain involved with emotion has been established. There is debate among scientists over whether or not humans are the only animals that produce tears in response to emotional states.Charles Darwin wrote in The Expression of the Emotions in Man and Animals that the keepers of Indian elephants in the London Zoo told him that their charges shed tears in sorrow.
Crying is an album released in 1962 by Roy Orbison. It was his second album on the Monument Record label. The album name comes from the 1961 hit song of the same name that in 2002 was honored with a Grammy Hall of Fame Award. In 2004, the song ranked #69 on Rolling Stone Magazine's "500 Greatest Songs of All Time".
All tracks composed by Roy Orbison and Joe Melson, except where indicated.
Crying is the human production of tears in response to an emotional state.
Crying may also refer to: