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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]

An ion optical design of a high resolution multi-turn time-of-flight mass analyzer (MT-TOF MA) is presented. The analyzer has rotationally symmetric main electrodes with additional mirror symmetry about a mid-plane orthogonal to the axis of symmetry. Rotational symmetry allows a higher density of turns in the azimuthal (drift) direction compared to MT-TOF MAs that are linearly extended in the drift direction. Mirror symmetry about a mid-plane helps to achieve a high spatial isochronicity of the ions' motion. The analyzer comprises a pair of polar-toroidal sectors S1 and S3, a pair of polar (trans-axial) lenses, and a pair of conical lenses for longitudinal and lateral focusing. A toroidal sector S2 located at the mid-plane of the analyzer has a set of embedded drift focusing segments providing focusing and spatial isochronicity in the drift direction. The ions' drift in the azimuthal direction can be reversed by using dedicated reversing deflectors. This gives the possibility of several operational modes with different numbers of turns and passes in the drift direction. According to numerical simulations, the mass resolving power of the analyzer ranges from ∼ 40 k (fwhm) at small (typically below ten) numbers of turns to ∼ 450 k (fwhm) at 96 turns. [ABSTRACT FROM AUTHOR]

An ion-optical design of a new sector field multi-turn time-of-flight analyzer is proposed. The analyzer forms oval-type spiral ion trajectories and possesses second order time-of-flight focusing with respect to both energy and spatial (coordinate and angular) spreads in ion packets. The analyzer is based on a combination of cylindrical electrostatic sectors and a periodic array of 2D lenses. The energy and spatial acceptances of the analyzer are compatible with the acceptances of existing multi-reflection analyzers based on planar ion mirrors, while, according to simulations, the space charge capacity of the sector field analyzer is essentially larger than of the mirror-type ones. Image 1 [ABSTRACT FROM AUTHOR]

Based on the analysis of the results of the study of various designs of multi-electrode harmonized Kingdon traps, we propose a new type of trap with two merged internal electrodes that has the ability to capture and accumulate ions formed inside. We also investigated the influence of inaccuracies in the manufacture of the electrodes on the field inside such trap. The four-electrode trap, which actually degenerates into a two-electrode device with traces of two other electrodes present at the ends of the internal electrodes (their splitting) has been found as the less sensitive to inaccuracies caused by manufacturing and cutting the ends of trap electrodes. We show that a mass spectrometer with a relatively high resolving power can be created on the basis of such a trap. The creation of the traps requires the manufacture of complex electrodes with demanded accuracy of their surfaces. This becomes possible with the advent of 3D printers.Multi electrode harmonize Kingdon trap with fused elctrode pares [ABSTRACT FROM AUTHOR]

The paper summarizes original developments of gridless ion mirrors for high-resolution multi-reflection time-of-flight mass spectrometers (MR TOF MS). Optimized mirror geometries and electrostatic field distributions reach up to the 5th order isochronicity with respect to the energy spread and up to the 3rd order full isochronicity per energy, spatial and angular spreads of ion packets. Using a retarding focusing field at the mirror entrance doubles the ion transport energy at limited highest voltages. In planar analyzers with a zig-zag ion path, quasi-planar mirrors eliminate the 2nd order dependence of the flight time on the ion packet width in the drift direction. Improved MR TOF analyzers of 1 m size provide well over one million aberration limit at realistic ion packets parameters past orthogonal accelerators. Because of high order isochronicity the aberration limit rapidly grows with the analyzer size or when using narrower ion packets. In experiments, improved analyzers with one meter size demonstrate up to 300 000 mass resolving power at the full mass range and 500 000 at the restricted mass range. Improved ion mirrors with two-dimensional electrostatic fields are applicable for TOF MS, electrostatic traps and open electrostatic traps in planar and hollow cylindrical geometries. [ABSTRACT FROM AUTHOR]

A novel three-dimensional square ion trap is reported as a mass analyzer or an ion transfer device. The square ion trap was constructed with six square planar electrodes while the electric field was optimized by changing their relative positions to arrange the strength of higher-order fields. Ion trajectory simulations demonstrate the square ion trap efficiently operates with radial and axial excitation. Additionally, ions ejected from the radial direction contained lower kinetic energies and their energy distribution were more centralized. These properties may improve the ion transfer efficiency. [ABSTRACT FROM PUBLISHER]

Ion capture from an external nano-electrospray ionization source in an electrostatic linear ion trap has been effected by in-trap potential lift so as to avoid a time-dependent frequency drift of trapped ions. This phenomenon was observed when using mirror switching for capturing ions and compromised the mass resolution when using Fourier transform techniques for mass determination. A dual image charge detection approach was also implemented to compensate for losses in mass resolution associated with increasing the length of the electrostatic trap to accommodate the lift region. The potential lift approach for ion capture led to no detectable frequency shifts, thereby enabling the achievement of pressure-limited theoretical resolutions. For example, a resolution of roughly 11,000 M/ΔM FWHM was observed for a carborane anion population of average m / z = 520 at a transient length of 125 ms. The use of the dual detector approach led to an increase (∼12%) in the ion frequencies used for mass analysis, which more than compensated for the effect of increasing the length of the electrostatic trap. Although the implementation of the potential lift approach and dual detectors were successful in their objectives, these changes resulted in a narrower m / z range for a single ion injection event relative to mirror switching. Furthermore, the dual detector approach resulted in a higher noise floor and a more complicated frequency spectrum due to asymmetries in the electric fields of the ion trap. [ABSTRACT FROM AUTHOR]

Some atomic collision experiments lead to ions having identical q/m ratio, as well as average velocity, so that standard electric and magnetic analyzers are not able to identify them separately. This situation occurs, for instance, in electron interaction with molecular monocations (A2+) producing A22+ (direct ionization) and A+ (dissociation or dissociative ionization). Due to the transfer of internal energy to the kinetic energy of the fragments, they usually have a wider angular and energy distribution in the laboratory frame, compared to direct ionization. By use of a specially designed animated crossed beams apparatus, we are able to separate ionization and dissociation fragments. Here the preliminary results of cross sections measurements for electron impact on the nitrogen monocation, producing N22+ and N+ ions, is reported.

Some atomic collision experiments lead to ions having identical q/m ratio, as well as average velocity, so that standard electric and magnetic analyzers are not able to identify them separately. This situation occurs, for instance, in electron interaction with molecular monocations (A2+) producing A22+ (direct ionization) and A+ (dissociation or dissociative ionization). Due to the transfer of internal energy to the kinetic energy of the fragments, they usually have a wider angular and energy distribution in the laboratory frame, compared to direct ionization. By use of a specially designed animated crossed beams apparatus, we are able to separate ionization and dissociation fragments. Here the preliminary results of cross sections measurements for electron impact on the nitrogen monocation, producing N22+ and N+ ions, is reported.

A novel linear ion trap mass analyzer featuring half round rod electrodes (HreLIT) has been built. It is mainly composed of two pairs of stainless steel electrodes which have a cross-section of half round rod and a pair of end electrodes. The HreLIT has a simple structure and so it could be assembled by hand with relatively high mechanical accuracy. The external dimension of HreLIT is 50 mm × 29.5 mm × 28 mm (length × width × height) and its internal volume is about 3.8 cm. A home-made HreLIT mass spectrometer with three-stage vacuum system was built and the performance of HreLIT was characterized using reserpine solution and PPG standard solution. When the scan rate was 254 u/s, mass peak with FWHM of 0.14 u was achieved for ions with m/z 609, which corresponds to a mass resolution of 4350. The HreLIT was also operated at a low q value of 0.28 to extend its mass range. The experiment result showed a mass range of over 2800 u and the amplitude of radio frequency (rf) signal was only 1560 V (0-p). Three-stage tandem mass spectrometry was successfully performed in the HreLIT, and the collision-induced dissociation (CID) efficiencies of MS (CID of ions with m/z 609) and MS (CID of ions with m/z 448) were 78% and 59%, respectively. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]