lower sieve

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• Sieve analysis — A sieve analysis is a practice or procedure used to assess the particle size distribution of a granular material. The size distribution is often of critical importance to the way the material performs in use. A sieve analysis can be performed on… …   Wikipedia

• lower vascular plant — ▪ biology Introduction formerly  pteridophyte,  also called  vascular cryptogam,         any of the spore bearing vascular plants, including the ferns, club mosses, spike mosses, quillworts, horsetails, and whisk ferns. Once considered of the… …   Universalium

• sieve cell — noun : an elongated tapering cell characteristic of the phloem of gymnosperms and lower vascular plants that is basically similar in form, function, and relationships to a sieve tube element but distinguished by rather uniformly distinguished… …   Useful english dictionary

• Legendre sieve — In mathematics, the Legendre sieve is the simplest method in modern sieve theory. It applies the concept of the Sieve of Eratosthenes to find upper or lower bounds on the number of primes within a given set of integers. Because it is a simple… …   Wikipedia

• Parity problem (sieve theory) — In number theory, the parity problem refers to a limitation in sieve theory that prevents sieves from giving good estimates in many kinds of prime counting problems. The problem was identified and named by Atle Selberg in 1949. Beginning around… …   Wikipedia

• Threshing machine — The thrashing machine, or, in modern spelling, threshing machine (or simply thresher), was a machine first invented by Scottish mechanical engineer Andrew Meikle for use in agriculture. It was invented (c.1784) for the separation of grain from… …   Wikipedia

• angiosperm — /an jee euh sperrm /, n. Bot. a plant having its seeds enclosed in an ovary; a flowering plant. Cf. gymnosperm. [ANGIO + SPERM] * * * ▪ plant Introduction       any member of the more than 300,000 species of flowering plants (division Anthophyta) …   Universalium

• petroleum refining — Introduction  conversion of crude oil into useful products. History Distillation of kerosene and naphtha       The refining of crude petroleum owes its origin to the successful drilling of the first oil well in Titusville, Pa., in 1859. Prior to… …   Universalium

• Multiplication algorithm — A multiplication algorithm is an algorithm (or method) to multiply two numbers. Depending on the size of the numbers, different algorithms are in use. Efficient multiplication algorithms have existed since the advent of the decimal system.… …   Wikipedia

• Vacuum swing adsorption — Vacuum Swing Absorption (VSA) is a non cryogenic gas separation technology. Using special solids, or absorbents, VSA segregates certain gases from a gaseous mixture under minimal pressure according to the species molecular characteristics and… …   Wikipedia

• Activated carbon — Activated carbon, also called activated charcoal, activated coal or carbo activatus, is a form of carbon that has been processed to make it extremely porous and thus to have a very large surface area available for adsorption or chemical reactions …   Wikipedia