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- إدغار بكنغهام (بالإنجليزية: Edgar Buckingham) هو كيميائي ورياضياتي وفيزيائي أمريكي، ولد في 8 يوليو 1867 في فيلادلفيا في الولايات المتحدة، وتوفي في 29 أبريل 1940 في واشنطن العاصمة في الولايات المتحدة. (ar)
- Edgar Buckingham (* 8. Juli 1867 in Philadelphia; † 29. April 1940 in Washington, D.C.) war ein US-amerikanischer Physiker und Bodenmechaniker. (de)
- Edgar Buckingham (July 8, 1867 in Philadelphia, Pennsylvania – April 29, 1940 in Washington DC) was an American physicist. He graduated from Harvard University with a bachelor's degree in physics in 1887. He did graduate work at Strasbourg and then studied under the chemist Wilhelm Ostwald at Leipzig, from which he was granted a PhD in 1893. He worked at the USDA Bureau of Soils from 1902 to 1906 as a soil physicist. He worked at the (US) National Bureau of Standards (now the National Institute of Standards and Technology, or NIST) 1906–1937. His fields of expertise included soil physics, gas properties, acoustics, fluid mechanics, and blackbody radiation. He is also the originator of the Buckingham π theorem in the field of dimensional analysis. In 1923, Buckingham published a report which voiced skepticism that jet propulsion would be economically competitive with prop driven aircraft at low altitudes and at the speeds of that period. Buckingham's first work on soil physics is on soil aeration, particularly the loss of carbon dioxide from the soil and its subsequent replacement by oxygen. From his experiments he found that the rate of gas diffusion in soil was not dependent significantly on the soil structure, compactness or water content of the soil. Using an empirical formula based on his data, Buckingham was able to give the diffusion coefficient as a function of air content. This relation is still commonly cited in many modern textbooks and used in modern research. The outcomes of his research on gas transport were to conclude that the exchange of gases in soil aeration takes place by diffusion and is sensibly independent of the variations of the outside barometric pressure. Buckingham then worked on soil water, research for which he is now renowned. Buckingham's work on soil water is published in Bulletin 38 USDA Bureau of Soils: Studies on the movement of soil moisture, which was released in 1907. This document contained three sections, the first of which looked at evaporation of water from below a layer of soil. He found that soils of various textures could strongly inhibit evaporation, particularly where capillary flow through the uppermost layers was prevented. The second section of Bulletin 38 looked at the drying of soils under arid and humid conditions. Buckingham found evaporative losses were initially higher from the arid soil, then after three days the evaporation under arid conditions became less than under humid conditions, with the total loss ending up greater from the humid soil. Buckingham believed this occurred due to the self-mulching behaviour (he referred to it as the soil forming a natural mulch) exhibited by the soil under arid conditions. The third section of Bulletin 38 contains the work on unsaturated flow and capillary action for which Buckingham is famous. He firstly recognized the importance of the potential of the forces arising from interactions between soil and water. He called this the capillary potential, this is now known as the moisture or water potential (matric potential). He combined capillary theory and an energy potential in soil physics theory, and was the first to expound the dependence of soil hydraulic conductivity on capillary potential. This dependence later came to be known as relative permeability in petroleum engineering. He also applied a formula equivalent to Darcy's law to unsaturated flow. (en)
- Edgar Buckingham (8 de julio de 1867 en Filadelfia, Estados Unidos — 29 de abril de 1940 en Washington D.C., EE. UU.) fue un físico estadounidense. Se graduó en física en la Universidad de Harvard en el año 1887, formación que continuó en la Universidad de Estrasburgo y en la Universidad de Leipzig, donde estudió bajo la tutela del químico Wilhelm Ostwald y donde finalmente se doctoró en 1893. Trabajó en la Oficina de Suelos del Departamento de Agricultura de los Estados Unidos (USDA Bureau of Soils) entre 1902 y 1906 como físico del suelo. Asimismo, trabajó en la National Bureau of Standards, actual Instituto Nacional de Estándares y Tecnología de EE. UU., entre 1906 y 1937. Sus especialidades incluían la física del suelo, los gases y sus propiedades, la acústica, la mecánica de fluidos y la radiación de cuerpos negros. En el campo del análisis dimensional, fue el autor del teorema pi, llamado también teorema π de Vaschy-Buckingham en su honor. Sus estudios acerca de la física del suelo tuvieron como temas principales la aireación del suelo y la hidratación del suelo. En cuanto al primero, se centró en la pérdida de dióxido de carbono en los suelos y en su sustitución por oxígeno. Dedujo que la difusión de los gases en el suelo no dependía de manera significativa de la estructura ni de la composición del terreno, ni tampoco de su contenido en agua. Sus investigaciones acerca del agua del suelo son más conocidas y le otorgaron mayor relevancia. Su trabajo Studies on the movement of soil moisture, publicado en 1907, se divide en tres partes, en las que trata la evaporación de agua desde el inferior de una capa de terreno, la desecación de suelos en condiciones secas y húmedas y, por último, los flujos insaturados y los efectos de la capilaridad y las interacciones moleculares entre agua y suelo. En esta última parte tiene su origen el concepto de potencial hídrico. (es)
- Edgar Buckingham, né le 8 juillet 1867 à Philadelphie, Pennsylvanie et mort le 29 avril 1940 à Washington DC, est un physicien-expert du National Bureau of Standards, passé à la postérité pour ses contributions à l'analyse dimensionnelle. (fr)
- Edgar Buckingham (Filadelfia, 8 luglio 1867 – Washington, 29 aprile 1940) è stato un fisico, matematico e chimico statunitense. Si è laureato in fisica ad Harvard nel 1887. Continuò gli studi presso l'università di Strasburgo e quella di Lipsia dove ebbe come professore il chimico Premio Nobel Wilhelm Ostwald. Ottenne il PhD a Lipsia nel 1893. Ha lavorato presso il USDA Bureau of Soils dal 1902 al 1906 come fisico del suolo. Durante gli anni 1906-1937 ha lavorato presso il (USgo) National Bureau of Standards (attualmente National Institute of Standards and Technology, o NIST). I suoi campi di applicazione hanno riguardato la fisica del suolo, le proprietà dei gas, l'acustica, la fluidodinamica e la radiazione del corpo nero. A lui si deve il Teorema di Buckingham detto anche teorema del pi greco. (it)
- Эдгар Букингем (англ. Edgar Buckingham; 8 июля 1867, Филадельфия, Пенсильвания, США — 29 апреля 1940, Вашингтон, США) — американский учёный-физик. (ru)
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- إدغار بكنغهام (بالإنجليزية: Edgar Buckingham) هو كيميائي ورياضياتي وفيزيائي أمريكي، ولد في 8 يوليو 1867 في فيلادلفيا في الولايات المتحدة، وتوفي في 29 أبريل 1940 في واشنطن العاصمة في الولايات المتحدة. (ar)
- Edgar Buckingham (* 8. Juli 1867 in Philadelphia; † 29. April 1940 in Washington, D.C.) war ein US-amerikanischer Physiker und Bodenmechaniker. (de)
- Edgar Buckingham, né le 8 juillet 1867 à Philadelphie, Pennsylvanie et mort le 29 avril 1940 à Washington DC, est un physicien-expert du National Bureau of Standards, passé à la postérité pour ses contributions à l'analyse dimensionnelle. (fr)
- Эдгар Букингем (англ. Edgar Buckingham; 8 июля 1867, Филадельфия, Пенсильвания, США — 29 апреля 1940, Вашингтон, США) — американский учёный-физик. (ru)
- Edgar Buckingham (July 8, 1867 in Philadelphia, Pennsylvania – April 29, 1940 in Washington DC) was an American physicist. He graduated from Harvard University with a bachelor's degree in physics in 1887. He did graduate work at Strasbourg and then studied under the chemist Wilhelm Ostwald at Leipzig, from which he was granted a PhD in 1893. He worked at the USDA Bureau of Soils from 1902 to 1906 as a soil physicist. He worked at the (US) National Bureau of Standards (now the National Institute of Standards and Technology, or NIST) 1906–1937. His fields of expertise included soil physics, gas properties, acoustics, fluid mechanics, and blackbody radiation. He is also the originator of the Buckingham π theorem in the field of dimensional analysis. (en)
- Edgar Buckingham (8 de julio de 1867 en Filadelfia, Estados Unidos — 29 de abril de 1940 en Washington D.C., EE. UU.) fue un físico estadounidense. Se graduó en física en la Universidad de Harvard en el año 1887, formación que continuó en la Universidad de Estrasburgo y en la Universidad de Leipzig, donde estudió bajo la tutela del químico Wilhelm Ostwald y donde finalmente se doctoró en 1893. Trabajó en la Oficina de Suelos del Departamento de Agricultura de los Estados Unidos (USDA Bureau of Soils) entre 1902 y 1906 como físico del suelo. Asimismo, trabajó en la National Bureau of Standards, actual Instituto Nacional de Estándares y Tecnología de EE. UU., entre 1906 y 1937. Sus especialidades incluían la física del suelo, los gases y sus propiedades, la acústica, la mecánica de fluidos y (es)
- Edgar Buckingham (Filadelfia, 8 luglio 1867 – Washington, 29 aprile 1940) è stato un fisico, matematico e chimico statunitense. Si è laureato in fisica ad Harvard nel 1887. Continuò gli studi presso l'università di Strasburgo e quella di Lipsia dove ebbe come professore il chimico Premio Nobel Wilhelm Ostwald. Ottenne il PhD a Lipsia nel 1893. Ha lavorato presso il USDA Bureau of Soils dal 1902 al 1906 come fisico del suolo. Durante gli anni 1906-1937 ha lavorato presso il (USgo) National Bureau of Standards (attualmente National Institute of Standards and Technology, o NIST). (it)
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