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Measurement of Atmospheric Pressure

Authors:
  • University of Guelph-Ontario Canada

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The atmospheric pressure on a given surface is the force exerted per unit area by the weight of the Earth’s atmosphere above. Atmospheric pressure is an important parameter for studying weather of a location and its interaction with the crops. The chapter includes various types of barometers used for the measurement of atmospheric pressure. The relation between atmospheric pressure and weather has been discussed in brief.
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Liquid metals are a class of materials with a millennia‐long history, albeit until 200 years ago, mostly centered on mercury‐based applications. The knowledge of mercury's toxicity and the discovery of it's bioaccumulation and biomagnification in the late 20th century resulted in phasing out mercury for copious application. Lead‐based, bismuth‐based, and sodium‐based technology has partially replaced mercury, but due to toxicity or reactivity issues, replacements for lead and sodium are sought. The discovery of indium and, especially, gallium has allowed for the third generation of alloys with a melting point close to room temperature. This review gives a comprehensive overview of the technological developments of fusible and liquid metals, i. e., metals and alloys with melting points below ca. 250 °C, from the early days to current research and industrial application. Special emphasis is focused on important steppingstones and recent developments of gallium‐based alloys as well as how they could be used for future applications.
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Agricultural hydrology as evaluated by monolith lysimeters 1944-1955
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Harrold, L.L. and Dreibelbis, F.R. (1967). Agricultural hydrology as evaluated by monolith lysimeters 1944-1955. USDA Technical Bulletin, (1367).
Decision support system for agrotechnology
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