Search

The concurrent utilization of electric and magnetic fields in static mass analyzers proves highly effective in sparticle separation solely based on their masses, thereby ensuring remarkable analytical capabilities. Highresolution mass analyzers employ an achromatizing electrostatic system to precisely focus ion radiation by energy. Devices featuring zero energy dispersion are created through the collaborative action of electric achromatizing systems and the magnetic field within the analyzer, resulting in ion separation based solely on mass. Expanding the ion beam prior to its magnetic field exposure enhances the overall quality of static mass analyzers. This article delves into a static mass analyzer with dual ion beam focusing, elucidating the ion acceleration and deceleration processes at electrode boundaries, their focalization via a transaxial lens, and the impact of the electrostatic prism's refractive surface on the mass analyzer's "quality" parameter. Additionally, the transition from a sector homogeneous magnetic field to the fields generated by a two-dimensional magnetic prism and a three-electrode transaxial focusing lens is explored to augment the mass analyzer's linear dispersion. To refine ion beam focus pre-magnetic field entry, the proposed adoption of a two-dimensional electrostatic prism promises heightened linear dispersion in the mass analyzer while expanding the beam pre-magnetic field entry. This study also examines the impact of a two-dimensional electric prism on the charged particle beam, presenting an approximate expression for its angular energy dispersion. It is demonstrated that a prism-based mass analyzer integrating two-dimensional electric and magnetic prisms enables energy-focused operations alongside enhanced linear dispersion and reduced linear dimensions. [ABSTRACT FROM AUTHOR]

A double potential well flat ion trap was designed as an ion accumulating and focusing device for multi-reflection time-of-flight mass analyzer. Two potential wells of the trap were severally used for accumulation of injected ions, controlled cooling and ejection of trapped ions, which had features to accumulate ions continuously and cool ion for almost one period. While a flat ion trap with only one potential well is a traditional and excellent ion accumulating and focusing device, which has an intermittent ion accumulation and an ion cooling around half period. Compared with the single potential well flat ion trap, the double potential well flat ion trap had better performance on ion accumulation and focusing in principle. Four steps to run the trap were simulated and researched by an ion optics simulator of SIMION 8.1. The first step was ion accumulation, ions were successively injected into the trap, and then stored and accumulated in the first potential well. The second step was ion transfer, the trapped ions were transferred from the first potential well to the second potential well. The third step was ion cooling, the trapped ions were confined in the second potential well, and were simultaneously cooled by collisions with 0.5 Pa He. The fourth step was ion ejection, the trapped ions were ejected from the trap and focused into the next device. Ion optics simulations indicated that the trap had a period from 1 ms to above 10 ms, a total ion transmission efficiency of 83%, and an ion flux of at most 1.6×106 ions. In addition, ion packets ejected from the trap had thermalized with radial diameters of 1.0 and 1.0 mm, angular standard deviations of 24 mrad and 16 mrad, and an energy standard deviation of 15 eV. This trap can be coupled with and provide high-flux and full-focusing ion packets for multi-reflection time-of-flight mass analyzers, due to an excellent suitability between the operation of the analyzer and the period, the ion transmission efficiency, the ion flux, and ejected ion packets of the trap.

Mass spectrometers are essential instruments for in situ analysis of planetary materials. Ideally, a space flight mass spectrometer would have a mass range from ∼10 u to at least 500 u to enable analysis of organic molecules to aid in searching for the requirements for life; capability for high precision isotope ratios of carbon, nitrogen, oxygen, sulfur, and noble gases to understand solar system evolution and functioning; and ability to resolve isobaric interferences at low m/z such as CO and N 2 to study planetary atmospheres. Despite the considerable progress in flight mass spectrometry since the 1970s, no single flight mass spectrometer has all these ideal characteristics. In this paper, we present a proof-of-concept super-resolution coded aperture cycloidal miniature mass spectrometer (SR-CAMMS) for planetary science. Design considerations and preliminary results are presented including: a mass range of 10–260 u with resolution of 0.5 u or better; the ability to resolve the isobaric interference between CO and N 2 at m/z = 28 u using sampling-super resolution; and the ability to acquire isotope ratios with Poisson statistics limited precision. Thus, the instrument met all design considerations except mass range, which was expected to be 10–500 u; reasons for this discrepancy are discussed in the paper. [Display omitted] • Super-resolution coded aperture miniature mass spectrometer: (SR-CAMMS). • Combines cycloidal mass analyzers, coded apertures, super-resolution, array detectors. • SR-CAMMS demonstrates mass range of 10–270 with 0.5 u or better resolution. • SR-CAMMS demonstrates isobaric separation of N 2 and CO using super-resolution. • SR-CAMMS demonstrates Poisson statistics limited isotope ratio precision with N 2. [ABSTRACT FROM AUTHOR]

A double potential well flat ion trap was designed as an ion accumulating and focusing device for multi-reflection time-of-flight mass analyzer. Two potential wells of the trap were severally used for accumulation of injected ions, controlled cooling and ejection of trapped ions, which had features to accumulate ions continuously and cool ion for almost one period. While a flat ion trap with only one potential well is a traditional and excellent ion accumulating and focusing device, which has an intermittent ion accumulation and an ion cooling around half period. Compared with the single potential well flat ion trap, the double potential well flat ion trap had better performance on ion accumulation and focusing in principle. Four steps to run the trap were simulated and researched by an ion optics simulator of SIMION 8.1. The first step was ion accumulation, ions were successively injected into the trap, and then stored and accumulated in the first potential well. The second step was ion transfer, the trapped ions were transferred from the first potential well to the second potential well. The third step was ion cooling, the trapped ions were confined in the second potential well, and were simultaneously cooled by collisions with 0.5 Pa He. The fourth step was ion ejection, the trapped ions were ejected from the trap and focused into the next device. Ion optics simulations indicated that the trap had a period from 1 ms to above 10 ms, a total ion transmission efficiency of 83%, and an ion flux of at most 1.6×106 ions. In addition, ion packets ejected from the trap had thermalized with radial diameters of 1.0 and 1.0 mm, angular standard deviations of 24 mrad and 16 mrad, and an energy standard deviation of 15 eV. This trap can be coupled with and provide high-flux and full-focusing ion packets for multi-reflection time-of-flight mass analyzers, due to an excellent suitability between the operation of the analyzer and the period, the ion transmission efficiency, the ion flux, and ejected ion packets of the trap. [ABSTRACT FROM AUTHOR]

This review describes the importance of UHPLC-MS in different fields and highlights the advancement in this hyphenated technique. The hyphenation of UHPLC-MS provides a standard modernized platform for many applications in pharmaceutics, environmental analysis, food industry and forensic science. The features of UHPLC-MS are higher degree of automation, shorter analysis time, better reproducibility and higher sensitivity which make this technique superior to other hyphenated techniques. [ABSTRACT FROM AUTHOR]

We report the effect of N2 gas‐mixing in the xenon electron cyclotron resonance (ECR) plasma, and abundance‐dependent novel, exciting and unusual trends of the isotope anomaly. The xenon plasma was produced using a 10 GHz all‐permanent‐magnet NANOGAN ECR ion source, and the charge state distributions of naturally abundant six stable xenon isotopes with and without N2 gas‐mixing (at 25%, 50%, and 75%) were recorded. The intensity ratio of the heavier to lighter isotope, where the heavier isotope is less abundant, showed a clear signature of the isotope anomaly as explained by the linear Landau wave damping theory. Contrary to the theoretical prediction that the isotope anomaly should vanish with a relatively large fraction of the heavier isotope in mixed plasmas, the trends of intensity ratios observed in such cases are very unusual and have almost the mirror‐symmetrical shapes of those trends recorded with less abundant heavier isotope. Further, the effect of relative mass difference on the isotope anomaly was also evidenced. The N2 gas‐mixing of the xenon plasma at 25% and 50% shifted the entire charge state distribution toward the higher intensity side owing to the supply of additional electrons that caused high ionization efficiency. However, a prominent gas‐mixing effect was observed at 75% of N2 mixing in the xenon plasma beyond the +7 charge state. The abundance‐dependent unusual trends in isotope anomaly have been explained by considering different ionic temperatures, ion heating by the wave damping, and Coulomb scattering in the core of the plasma. [ABSTRACT FROM AUTHOR]

With the advent of technologies such as ion array detectors and high energy permanent magnet materials, there is renewed interest in the unique focusing properties of the cycloidal mass analyzer and its ability to enable small, high‐resolution, and high‐sensitivity instruments. However, most literature dealing with the design of cycloidal mass analyzers assumes a single channel detector because at the time of those publications, compatible multichannel detectors were not available. This manuscript introduces and discusses considerations and a procedure for designing cycloidal mass analyzers coupled with focal plane ion array detectors. To arrive at a set of relevant design considerations, we first review the unique focusing properties of the cycloidal mass analyzer and then present calculations detailing how the dimensions and position of the focal plane array detector relative to the ion source determine the possible mass ranges and resolutions of a cycloidal mass analyzer. We present derivations and calculations used to determine the volume of homogeneous electric and magnetic fields needed to contain the ion trajectories and explore the relationship between electric and magnetic field homogeneity on resolving power using finite element analysis (FEA) simulations. A set of equations relating the electric field homogeneity to the geometry of the electric sector electrodes was developed by fitting homogeneity values from 78 different FEA models. Finally, a sequence of steps is suggested for designing a cycloidal mass analyzer employing an array detector. [ABSTRACT FROM AUTHOR]