maintain contamination
51Water purification — This article is about large scale, municipal water purification. For portable/emergency water purification, see portable water purification. For industrial water purification, see deionized water. For distilled water, see distilled water. Water… …
52Freshwater — is a word that refers to bodies of water such as ponds, lakes, rivers and streams containing low concentrations of dissolved salts and other total dissolved solids. In other words, the term excludes seawater and brackish water.Freshwater is an… …
53Brazing — This article is about the metal joining process. For the cooking technique, see braising. Brazing practice Brazing is a metal joining process whereby a filler metal is heated above and distributed between two or more close fitting parts by… …
54Water supply — is the process of self provision or provision by third parties of water of various qualities to different users. Irrigation is covered separately. Global access to waterIn 2004 about 3.5 billion people worldwide (54% of the global population) had …
55Pease Air Force Base — Infobox Military Structure name = Pease Air National Guard Base partof = New Hampshire Air National Guard (ANG) location = Located near Portsmouth, New Hampshire coordinates = coord|43|04|41|N|070|49|24|W|region:US type:airport caption = USGS… …
56Nuclear safety — covers the actions taken to prevent nuclear and radiation accidents or to limit their consequences. This covers nuclear power plants as well as all other nuclear facilities, the transportation of nuclear materials, and the use and storage of… …
57United States — a republic in the N Western Hemisphere comprising 48 conterminous states, the District of Columbia, and Alaska in North America, and Hawaii in the N Pacific. 267,954,767; conterminous United States, 3,022,387 sq. mi. (7,827,982 sq. km); with… …
58Hygrometer — Not to be confused with hydrometer. A hygrometer (UK: /haɪˈɡrɒmɪtə/) is an instrument used for measuring the moisture content in the environmental air, or humidity. Most measurement devices usually rely on measurements of some other quantity …
59Bas-Lag — is the fictional world in which several of China Miéville s novels are set. Bas Lag is a world where both magic (referred to as thaumaturgy ) and steampunk technology exist, and is home to many intelligent races. It is influenced by the themes… …
60Hand pump — This article is about water and air pumps. For the beer dispensing device, see Beer engine. A rural handpump in Belgium. Hand pumps are manually operated pumps; they use human power and mechanical advantage to move fluids or air from one place to …
