The monoisotopic masses of these compounds are 31.989829 Da (oxygen), 32.026215 Da (methanol), and 32.037448 Da (hydrazine).
In the spectrographs used by Thomson until 1910, the rays of positive electricity were detected by the phosphorescence they produced on a willemite screen. The screen was made by grinding rare zinc mineral willemite into a fine powder. After shaking in alcohol, the suspension was allowed to deposit slowly on a glass plate. Later, a photographic plate inside the spectrograph was used for more sensitive detection.
The first mass spectrometer in the country was built in the Laboratory of Physical Chemistry of the Czechoslovak Academy of Sciences. Four young scientists, Vladimír Čermák, Vladimír Hanuš, Čestmír Jech and Josef Cabicar, took part in its construction. At the time of the post-war shortage, it was very difficult to find the necessary components; some parts originated from captured German military equipment. The mass spectrometer was of the Nier type with simple focusing and 60° magnetic field, pumped by a mercury diffusion pump. The device was completed after two years, in 1953. The construction of this instrument was an extraordinary achievement awarded a year later by the State Prize. [Z. Herman, Chem. Listy 104, 955, 2010]
During the war, copper was preferably used for the production of brass shell casings and it was not available for the construction of calutrons. The designers came up with the idea of replacing copper with silver. They borrowed about 13,300 tons of silver from the West Point Bullion Depository in West Point, NY. After the war, the silver was returned to the Treasury with virtually no loss.
Chemical ionization was discovered in the laboratories of the Humble Oil and Refining Company in Baytown, TX. Munson and Field’s seminal paper on chemical ionization was published in 1966. [https://doi.org/10.1021/ja00964a001]
The magnetic force is perpendicular to the velocity so that it does no work on the charged particle. The particle’s kinetic energy and speed thus remain constant. The direction of motion is affected but not the speed.
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