Eur J Mass Spectrom (Chichester)
February 2018
The main advantages of laser sampling are associated with following features: sample preparations as well as consumables are not needed, low risk of sample contamination, good spatial resolution. In mass spectrometry, high laser irradiance can be used for both ablation and ionization processes. The method is especially profitable in time-of-flight mass spectrometry.
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August 2017
This article offers a new approach to computer modeling of time-of-flight analyzers of mass spectrometers. The main feature of the model is comprehensive tracking of the processes from the laser plasma generation until the final stage, on which the isotopic or elemental composition is determined for the analyzed solid sample. Apart from usual models based on SIMION-8 3D or similar software, this article proposes fundamentally new modeling stages.
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August 2017
It is shown that the main reason affecting the accuracy and reproducibility of the elemental analysis of solids with a laser source of ions is the difference in the ionization cross sections of different elements in the generation of laser plasma. Computer modeling was carried out for the evaporation of the sample and generation of laser plasma at different values of laser power density. The aim of modelling was to determine the cause of the low accuracy of analysis by direct selection of ions from the plasma.
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June 2017
An ion mobility time-of-flight mass spectrometry (IM-TOFMS)-based method has been preliminarily investigated for the identification of triphenylmethane ballpoint pen dyes on paper. The dyes were sampled from one-year-old ballpoint pen ink entries. The entries were written on paper documents stored in the dark in a bookcase.
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June 2017
The new ion-optical system of the laser time-of-flight (TOF) mass spectrometer on the basis of two tandem wedge-shape reflectors has been offered and implemented. A new method of correcting chromatic aberration by the ion energy was proposed that used a wire electrode unit with adjustable potentials. This unit allows one to adjust the local TOF of the ions in a narrow energy range ± (1-2)% within the total ion packet with an energy spread of ± 20%.
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February 2016
Aspects of a new type of laser time-of-flight mass spectrometer are described in this letter. It is based on a wedge-shaped reflecting mirror and is used as an ion analyzer. The analyzer provides time focusing by both energy and a divergence angle of ions.
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August 2015
A new approach to the formation of ultrashort laser ion packages in the ion source of time-of-flight (TOF) mass spectrometer for elemental analysis is described. This is achieved by installing a wedge-shaped reflector with special correcting plates. The reflector provides time and space focusing of the ion packages.
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June 2014
Characteristic ion mobility mass spectrometry data, reduced mobility, and limits of detection (signal-to-noise ratio = 3) were determined for six synthetic drugs and cocaine by ion mobility time-of-flight mass spectrometry (IM-TOF-MS) with electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI). The studied synthetic illicit drugs recently appeared on the recreational drug market as designer drugs and were methylone, 4-MEC (4'-methylethcathinone), 3,4-MDPV (3,4-methylenedioxypyrovalerone), JWH-210 [4-ethylnaphthalen-1-yl-(1-pentylindol-3-yl)methanone], JWH-250 [2-(2-methoxyphenyl)-1-(1-pentyl-1H-indol-3-yl)ethanone], and JWH-203 [1-pentyl-3-(2'-chlorophenylacetyl) indole]. Absolute reduced mobilities in nitrogen were 1.
View Article and Find Full Text PDFThe present review covers the main research in the area of mass spectrometry from the 1990s which was about the same time as the Russian Federation emerged from the collapse of the Soviet Union (USSR). It consists of two main parts-application of mass spectrometry to chemistry and related fields and creation and development of mass spectrometric technique. Both traditional and comparatively new mass spectrometric methods were used to solve various problems in organic chemistry (reactivity of gas-phase ions, structure elucidation and problems of identification, quantitative and trace analysis, differentiation of stereoisomers, derivatization approaches etc.
View Article and Find Full Text PDFRecently developed ion mobility mass spectrometer is described. The instrument is based on a drift tube ion mobility spectrometer and an orthogonal acceleration electrostatic sector time-of-flight mass analyzer. Data collection is performed using a specially developed fast ADC-based recorder that allows real-time data integration in an interval between 3 and 100 s.
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