parts-per-billion-level

См. также в других словарях:

• Parts-per notation — One part per trillion (1 ppt) is a proportion equivalent to one twentieth of a drop of water diluted into an Olympic size swimming pool. In science and engineering, the parts per notation is a set of pseudo units to describe small values of… …   Wikipedia

• Current sea level rise — This article is about the current and future rise in sea level associated with global warming. For sea level changes in Earth s history, see Sea level#Changes through geologic time. Sea level measurements from 23 long tide gauge records in… …   Wikipedia

• environment — environmental, adj. environmentally, adv. /en vuy reuhn meuhnt, vuy euhrn /, n. 1. the aggregate of surrounding things, conditions, or influences; surroundings; milieu. 2. Ecol. the air, water, minerals, organisms, and all other external factors… …   Universalium

• Perfluorooctanoic acid — IUPAC name pentadecafluorooctanoic acid …   Wikipedia

• dating — I In geology and archaeology, the process of determining an object s or event s place within a chronological scheme. Scientists may use either relative dating, in which items are sequenced on the basis of stratigraphic clues (see stratigraphy) or …   Universalium

• Kilogram — Kg redirects here. For other uses, see Kg (disambiguation). Kilogram A computer generated image of the international prototype kilogram (IPK). The IPK is the kilogram. The IPK, which is roughly the size of a golf ball, sits here alongside a ruler …   Wikipedia

• global warming — an increase in the earth s average atmospheric temperature that causes corresponding changes in climate and that may result from the greenhouse effect. [1975 80] * * * Potential increase in global average surface temperatures resulting from… …   Universalium

• Vermont — This article is about the U.S. state of Vermont. For other uses, see Vermont (disambiguation). State of Vermont …   Wikipedia

• Physical Sciences — ▪ 2009 Introduction Scientists discovered a new family of superconducting materials and obtained unique images of individual hydrogen atoms and of a multiple exoplanet system. Europe completed the Large Hadron Collider, and China and India took… …   Universalium

• spectroscopy — spectroscopist /spek tros keuh pist/, n. /spek tros keuh pee, spek treuh skoh pee/, n. the science that deals with the use of the spectroscope and with spectrum analysis. [1865 70; SPECTRO + SCOPY] * * * Branch of analysis devoted to identifying… …   Universalium

• Drinking water quality in the United States — is a source of concern about pollutants in certain localities. In 2006, 89.3 percent of the nation s community water systems were in compliance with all of more than 90 U.S. Environmental Protection Agency (EPA) standards.[1]:220 Most of the… …   Wikipedia