The chemical ionisation mass spectra of seven naturally occurring depsipeptides and some of their permethylated derivatives have been measured. The primary ionisation process involves an ester group and not an amide or other functionality. It probably occurs randomly when the molecule contains more than one ester link. Unlike electron impact mass spectra, those obtained under chemical ionisatio...

Abstract A least-squares fit of exponential functions to a measured radioactive decay rate curve provides an estimate the half-life and its statistical uncertainty in assumption that all deviations from theoretical are purely random nature. The result may be biased error underestimated as soon experiment suffers instabilities exceed duration individual measurements. Contrary long-term systemati...

Boron neutron capture therapy (BNCT) is a form of chemically targeted radiotherapy that utilises the high neutron capture cross-section of boron-10 isotope to achieve a preferential dose increase in the tumour. The BNCT dosimetry poses a special challenge as the radiation dose absorbed by the irradiated tissues consists of several dose components with different relative biological effectiveness...

Abstract Cyanoacetylene (HC 3 N) is an important trace species in the atmosphere of Titan. We report, for first time, absolute partial electron ionisation cross sections and precursor-specific cyanoacetylene, following experimental computational investigation. Our methodology involves using 2D ion-ion coincidence mass spectrometry to generate relative sections, over energy range 50 – 200 eV. Th...

We investigated the pressure dependence of gas flow and field ion intensity a coaxial source operating at room temperature over wide range, testing various gases ionisation voltages. Flow conductance measurements taking into account different gases' viscosity molecular mass consistently exhibit generic pattern. Three regimes appear with increasing upstream pressure. Since supplies locally, very...