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1NRX — For the NRX series of nuclear thermal rocket designs, see NERVA. NRX was a heavy water moderated, light water cooled, nuclear research reactor at the Canadian Chalk River Laboratories, which came into operation in 1947 at a design power rating of …
2Earth Sciences — ▪ 2009 Introduction Geology and Geochemistry The theme of the 33rd International Geological Congress, which was held in Norway in August 2008, was “Earth System Science: Foundation for Sustainable Development.” It was attended by nearly… …
3arts, 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… …
4Sedimentary rock — Middle Triassic marginal marine sequence of siltstones (below) and limestones (above), Virgin Formation, southwestern Utah, USA Sedimentary rock are types of rock that are formed by the deposition of material at the Earth s surface and within… …
5agricultural technology — Introduction application of techniques to control the growth and harvesting of animal and vegetable products. Soil preparation Mechanical processing of soil so that it is in the proper physical condition for planting is usually… …
6Drilling fluid — This article is about fluids used when drilling a well. For fluids used with drill bits during metal working, see cutting fluid. Driller pouring a foaming agent down the rod string on a drilling rig In geotechnical engineering, drilling fluid is… …
