The monoisotopic mass of an ion or molecule is defined as an exact mass and is determined by summing each mass of the most abundant isotope (e.g. 1H=1.00782, 12C=12.00000, 16O=15.99491, 14N=14.00307) present in the chemical formula. ...
Relative isotopic mass,英文定义如下: The relative isotopic mass of an atom is the ratio of its atomic mass to the atomic mass of a reference isotope of the same element. It is used to account for the different masses of atoms that have different isotopes....
Spectroscopy of a narrow-line optical pumping transition in atomic dysprosium We present measurements of the hyperfine coefficients and isotope shifts of the Dy I 683.731 nm transition, using saturated absorption spectroscopy on an a... M Schmitt,EAL Henn,J Billy,... - 《Optics Letters》 被引量...
Isotope-selective non-dispersive infrared spectrometry for detection of Helicobacter pylori infection with 13C-urea breath test. 13C-urea breath tests were sampled in 51 subjects with an isotope-selective non-dispersive infrared spectrometer (NDIRS) and compared with the results of conventional isotope...
The Kendrick mass defect (KMD) analysis of multiply charged polymeric distributions has recently revealed a surprising isotopic split in their KMD plots—namely a 1/z difference between KMDs of isotopes of an oligomer at charge state z. Relying on the KMD analysis of actual and simulated distribut...
In the field of isotope ratio mass spectrometry, the introduction of an interface allowing the connection of liquid chromatography (LC) and isotope ratio mass spectrometry (IRMS) has opened a range of new perspectives. The LC interface is based on a chemical oxidation, producing CO2 from organic...
We describe an efficient, precise and fast beam pulsing system for accelerator mass spectrometry. Precision of isotope ratio measurements for carbon are on the order of 1%. Thus the δ 13C values needed for radiocarbon age calculation co... M Suter,R Balzer,G Bonani,... - 《Nuclear Inst ...
The general-purpose averagine-based deconvolution procedure can be called by using the high level API function deconvolute_peaks, which takes a sequence of peaks, an averagine model, and a isotopic goodness-of-fit scorer:import ms_deisotope deconvoluted_peaks, _ = ms_deisotope.deconvolute_peaks...
The isotope tritium has a short half-life of 12.3 years and a low endpoint of 18.6 keV, both of which are favourable properties to achieve high count rates near the endpoint. Moreover, the theoretical calculation of the super-allowed decay of tritium is well understood25,26,27. The...
Long storage of gaseous samples also is difficult. Extended respiration studies are most easily conducted by trapping CO2 in alkali and conversion to an insoluble carbonate. Thermal decomposition of the carbonate in an online ANCA allows consistent and optimal CO2 sample mass to be obtained. The ...