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A new wiki encyclopedia project—and more! We aim at reliability and quality, not just quantity. We welcome collaboration with everyone who has knowledge, broad or narrow, about any of the world's innumerable subjects. We write under our real names—and are both collegial and congenial. We now have [[:Category:CZ Live|Template:Articles number+ articles]] and are gathering speed. Eduzendium participants write for academic credit. See what Nature wrote about us. Write for the Citizendium—knowledge is fun! Sign up—we need both authors and editors (you might be both!) Then, get a quick start. Remember, we are an open, young project—it's easy to get involved! Wikipedians are very welcome! Learn about us Why Citizendium? For readers: About | FAQ For contributors: Authors | Editors | How to collaborate For the press Important new community pages WatchKnow will be a free, non-profit, K-12 educational video contest, currently under planning and development. Myths and Facts: Citizendium may be different from what you think! We are organizing Workgroup Weeks—our biggest initiative yet. Citizens, get involved, and watch our numbers multiply! Cleanup—helps to develop, keep and maintain a coherent structure for entries in Citizendium. Support us Our mission is educational, non-profit, global, and free. Shop at our Amazon.com and Barnes & Noble links and we'll get donations at no cost to you. Link to us so search engines can better find us.   (CC) Photo: Tanya Puntti Each sentence you add is another drop in an expanding sea of words.

Some of our finest [ about ] Approved Articles Developed Articles (over 900) "The ink of the learned is equal in merit to the blood of the martyrs." —Father Kristoforos, Birds Without Wings, by Louis de Bernieres (b. 1954) Article of the Week [ about ] (PD) Photo: U. S. Environmental Protection Agency Large, shallow ground-level trickle filters in a municipal wastewater treatment plant Large-scale trickle filters are wastewater treatment facilities for biochemically oxidizing biodegradable substances present in wastewaters. They consist of a fixed bed of rocks, gravel, slag, polyurethane foam or plastic media over which sewage or other biodegradable wastewater percolates downward and is contacted with a layer or film of microbial slime covering the bed media. Aerobic conditions are maintained by air flowing through the bed. The terms trickling biofilter, biofilter, biofilm reactor, biological filter, biological trickling filter and biotower are often used to refer to a trickle filter. These systems have also been described as an attached growth process , a fixed film process, packed media bed filters, roughing filters and percolating filters. [more...] New Draft of the Week [ about ] Joseph Black (1728-1799), was a Scottish chemist and physicist, known for the concepts of latent heat and specific heat, and for the discovery of carbon dioxide. He was a founder of thermochemistry, and was the mentor of James Watt. Black was a member of the Poker Club and friend of David Hume, Adam Smith, James Hutton and other leading figures of the Scottish Enlightenment. Joseph Black was one of fifteen children (8 sons and 5 daughters surviving). His father, John Black, was a wine merchant; his mother, Margaret, was from Aberdeenshire. At the age of twelve, he was sent to a grammar school in Belfast to learn Latin and Greek. In 1744 he enrolled at Glasgow University to study arts, subsequently changing, to study medicine. There, William Cullen was his instructor in chemistry, and the relation between the two soon became that of professor and assistant rather than of master and pupil. [more...]