# regular+arrangement

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**Sphere packing**— In mathematics, sphere packing problems are problems concerning arrangements of non overlapping identical spheres which fill a space. Usually the space involved is three dimensional Euclidean space. However, sphere packing problems can be… …22

**eye, human**— ▪ anatomy Introduction specialized sense organ capable of receiving visual images, which are then carried to the brain. Anatomy of the visual apparatus Structures auxiliary to the eye The orbit The eye is protected from mechanical injury… …23

**Close-packing of spheres**— hcp and fcc close packing of spheres In geometry, close packing of spheres is a dense arrangement of equal spheres in an infinite, regular arrangement (or lattice). Carl Friedrich Gauss proved that the highest average density – that is, the… …24

**transition element**— Chem. any element in any of the series of elements with atomic numbers 21 29, 39 47, 57 79, and 89 107, that in a given inner orbital has less than a full quota of electrons. Also called transition metal. [1920 25] * * * Any chemical element with …25

**Mathematics and Physical Sciences**— ▪ 2003 Introduction Mathematics Mathematics in 2002 was marked by two discoveries in number theory. The first may have practical implications; the second satisfied a 150 year old curiosity. Computer scientist Manindra Agrawal of the… …26

**Collagen**— Tropocollagen triple helix Collagen /ˈkɒlədʒɨn/ is a group of naturally occurring proteins found in animals, especially in the flesh and connective tissues of mammals.[1] It is the main component of connectiv …27

**symmetry**— I (New American Roget s College Thesaurus) Regularity of form Nouns symmetry, proportion, balance, parallelism; uniformity, correspondence, congruity, regularity, regular arrangement; order, harmony, eurythmy; shapeliness, form, beauty,… …28

**lattice**— A regular arrangement of units into an array such that a plane passing through two units of a particular type or in a particular interrelationship will pass through an indefinite number of such units; e.g., the atom arrangement in a crystal. * *… …29

**Crystallization of polymers**— Spherulites viewed between crossed polarizers in an optical microscope. Crystallization of polymers is a process associated with partial alignment of their molecular chains. These chains fold together and form ordered regions called lamellae,… …30

**Cerebellum**— This article is about the smaller region in the lower part of the brain. For the large region of the brain, see Cerebrum. Brain: Cerebellum A human brain, with the cerebellum colored in purple …