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X-ray photoelectron spectroscopy is a chemical analysis technique relying on the photoelectric effect, usually employed in surface science. Radiation implosion is the use of high energy X-rays generated from a fission explosion (an A-bomb) to compress nuclear fuel to the point of fusion ignition (an H-bomb).
Moseley's law is an empirical law concerning the characteristic X-rays emitted by atoms. The law had been discovered and published by the English physicist Henry Moseley in 1913–1914. [1][2] Until Moseley's work, "atomic number" was merely an element's place in the periodic table and was not known to be associated with any measurable physical ...
A replica of an apparatus used by Geiger and Marsden to measure alpha particle scattering in a 1913 experiment. The Rutherford scattering experiments were a landmark series of experiments by which scientists learned that every atom has a nucleus where all of its positive charge and most of its mass is concentrated.
This became the classic means of measuring the charge-to-mass ratio of the electron. (The charge itself was not measured until Robert A. Millikan's oil drop experiment in 1909.) Thomson believed that the corpuscles emerged from the atoms of the trace gas inside his cathode ray tubes. He thus concluded that atoms were divisible, and that the ...
A mass spectrometer in use at NIH in 1975. The history of mass spectrometry has its roots in physical and chemical studies regarding the nature of matter. The study of gas discharges in the mid 19th century led to the discovery of anode and cathode rays, which turned out to be positive ions and electrons. Improved capabilities in the separation ...
He found that for 224 grains of "fixed air" (CO 2) produced, 13 oz (370 g). of ice was melted in the calorimeter. Converting grains to grams and using the energy required to melt 13 oz (370 g). of ice, one can compute that for each gram of CO 2 produced, about 2.02 kcal of energy was produced by the combustion of carbon or by respiration in ...
An X-ray spectrograph consists of a high voltage power supply (50 kV or 100 kV), a broad band X-ray tube, usually with a tungsten anode and a beryllium window, a specimen holder, an analyzing crystal, a goniometer, and an X-ray detector device. These are arranged as shown in Fig. 1. Fig. 1.
In 1895, the German physicist Wilhelm Conrad Röntgen discovered and extensively studied X-rays, which were later used in X-ray spectroscopy. One year later, in 1896, French physicist Antoine Henri Becquerel discovered radioactivity, and Dutch physicist Pieter Zeeman observed spectral lines being split by a magnetic field. [46] [13]