Similarity+of+crystalline+form
31photoreception — photoreceptive, adj. /foh toh ri sep sheuhn/, n. the physiological perception of light. [1905 10; PHOTO + RECEPTION] * * * Biological responses to stimulation by light, most often referring to the mechanism of vision. In one celled organisms such …
32India — /in dee euh/, n. 1. Hindi, Bharat. a republic in S Asia: a union comprising 25 states and 7 union territories; formerly a British colony; gained independence Aug. 15, 1947; became a republic within the Commonwealth of Nations Jan. 26, 1950.… …
33metallurgy — metallurgic, metallurgical, adj. metallurgically, adv. metallurgist /met l err jist/ or, esp. Brit., /meuh tal euhr jist/, n. /met l err jee/ or, esp. Brit., /meuh tal euhr jee/, n. 1. the technique or science of working or heating metals so as… …
34List of Doctor Who universe creatures and aliens — This is a list of fictional creatures and aliens from the universe of the long running BBC science fiction television series Doctor Who, including Torchwood, The Sarah Jane Adventures and K 9. It covers alien races and other fictional creatures,… …
35plate tectonics — plate tectonic, adj. Geol. a theory of global tectonics in which the lithosphere is divided into a number of crustal plates, each of which moves on the plastic asthenosphere more or less independently to collide with, slide under, or move past… …
36Penrose tiling — A Penrose tiling is a nonperiodic tiling generated by an aperiodic set of prototiles named after Roger Penrose, who investigated these sets in the 1970s.Because all tilings obtained with the Penrose tiles are non periodic, Penrose tilings are… …
37Africa — /af ri keuh/, n. 1. a continent S of Europe and between the Atlantic and Indian oceans. 551,000,000; ab. 11,700,000 sq. mi. (30,303,000 sq. km). adj. 2. African. * * * I Second largest continent on Earth. It is bounded by the Mediterranean Sea,… …
38Yttrium — (pronEng|ˈɪtriəm) is a chemical element with symbol Y and atomic number 39. It is a silvery metallic transition metal chemically similar to the lanthanoids and has historically been classified as a rare earth element. Yttrium is almost always… …
39drug use — Introduction use of drugs for psychotropic rather than medical purposes. Among the most common psychotropic drugs are opiates ( opium, morphine, heroin), hallucinogens (LSD, mescaline, psilocybin), barbiturates, cocaine, amphetamines,… …
40arts, East Asian — Introduction music and visual and performing arts of China, Korea, and Japan. The literatures of these countries are covered in the articles Chinese literature, Korean literature, and Japanese literature. Some studies of East Asia… …
