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skin patch

(Encyclopedia)skin patch, transdermal patch, or transdermal delivery system, adhesive patch used to deliver a controlled dose of a drug through the skin over a period of time. A skin patch uses a special membrane ...

microphone

(Encyclopedia)microphone, device for converting sound into electrical energy, used in radio broadcasting, recording, and sound amplifying systems. Its basic component is a diaphragm that responds to the pressure or...

Monte Albán

(Encyclopedia)Monte Albán mōnˈtā älbänˈ [key], ancient city, c.7 mi (11.3 km) from Oaxaca, SW Mexico, capital of the Zapotec. Monte Albán was built on an artificially leveled, rocky promontory above the Val...

Peabody, George

(Encyclopedia)Peabody, George pēˈbädē, –bədē [key], 1795–1869, American financier and philanthropist, b. South Danvers (now Peabody), Mass. At the age of 11 he was apprenticed to a grocer, and later (1814...

Safdie, Moshe

(Encyclopedia)Safdie, Moshe mōshāˈ säfˈdē [key], 1938–, Israeli-Canadian architect, b. Haifa. He grew up in Israel, moved to Canada with his family at 15, studied architecture at McGill Univ. and with Louis...

Ballard, J. G.

(Encyclopedia)Ballard, J. G. (James Graham Ballard) bălˈərd [key], 1930–2009, English writer, mainly of dystopian science fiction. Born to English parents in Shanghai, he was torn from his affluent surrounding...

silica

(Encyclopedia)silica or silicon dioxide, chemical compound, SiO2. It is insoluble in water, slightly soluble in alkalies, and soluble in dilute hydrofluoric acid. Pure silica is colorless to white. It occurs in sev...

chloropicrin

(Encyclopedia)chloropicrin klōrˌəpĭkˈrĭn [key], colorless oily liquid used as a poison gas. It is a powerful irritant, causing lachrymation, vomiting, bronchitis, and pulmonary edema; lung injury from chlorop...

antidiuretic hormone

(Encyclopedia)antidiuretic hormone ănˌtēdīyo͞orĕtˈĭk [key], polypeptide hormone secreted by the posterior pituitary gland. Its principal action is to regulate the amount of water excreted by the kidneys. An...

fusion

(Encyclopedia)fusion, in physics. 1 The change of a substance from the solid to the liquid state, also known as melting. The heat given up by a unit mass of a substance during fusion is called the latent heat of fu...