Mass spectrometry was used to sequence peptides for the first time in 1959 when K. Biemann described an innovative method based on the reduction of small peptides to polyamino alcohols with characteristic EI spectra. [https://doi.org/10.1021/ja01518a069]
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]
The particle carries one elementary charge, the value of which is 1.602 176 634 × 10−19 C (exactly).
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 resolution can be expressed as (m/z)/Δ(m/z), where Δ (m/z) is the peak width at 50 % of its maximum. For a resolution of 50,000 at m/z 500, the value of Δ(m/z) is 0.01. If the Δ(m/z) is to correspond to 1 mm, then the total width of the spectral record equals 1000/0.01 mm, which is 100,000 mm, which is 100 m.
The solution of differential equations of this type came from the French mathematician Émile Léonard Mathieu (1835-1890), who studied the mechanical vibrations of the elliptical drumheads.
The International Prototype of the Kilogram was a cylinder with a height and diameter of 39 mm made of an alloy of 90% platinum and 10% iridium.
His father, Joseph James Thomson, ran an antiquarian bookshop founded by Thomson’s great-grandfather. [Wikipedia]
Aston is a 44-kilometer lunar impact crater located along the northwestern limb of the Moon. The crater was named in honor of Francis W. Aston.
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