Ion-neutral transport through quadrupole interfaces of mass-spectrometer systems

International Nuclear Information System (INIS)

Jugroot, M.; Groth, C.P.T.; Thomson, B.A.; Baranov, V.; Collings, B.A.; French, J.B.

2004-01-01

The transport of free ions through highly under-expanded jet flows of neutral gases and in the presence of applied electric fields is investigated by continuum-based numerical simulations. In particular, numerical results are described which are relevant to ion flows occurring in quadrupole interfaces of mass spectrometer systems. A five-moment mathematical model and parallel multi-block numerical solution procedure is developed for predicting the ion transport. The model incorporates the effects of ion-neutral collision processes and is used in conjunction with a Navier-Stokes model and flow solver for the neutral gas to examine the key influences controlling the ion motion. The effects of the neutral gas flow, electric fields (both dc and rf), and flow field geometry on ion mobility are carefully assessed. The capability of controlling the charged particle motions through a combination of directed neutral flow and applied electric field is demonstrated for these high-speed, hypersonic, jet flows. (author)

Long-term changes in the sensitivity of quadrupole mass spectrometers

International Nuclear Information System (INIS)

Blanchard, W.R.; McCarthy, P.J.; Dylla, H.F.; LaMarche, P.H.; Simpkins, J.E.

1986-02-01

We routinely use quadrupole mass spectrometers (QMS) to monitor vacuum conditions, gas purity, and plasma-wall interactions in the Tokamak Fusion Test Reactor (TFTR) at Princeton. Two QMS systems have been operating on TFTR continuously for a two-year period. Both QMS systems are absolutely calibrated at weekly intervals using a six-part standard gas mixture. The calibration procedure is based on the use of transfer standards (ion gauge and capacitance manometer) that are calibrated against a primary standard (spinning rotor gauge) on an external vacuum system. We have identified variations in the efficiency of the QMS ionizer and drifts in the sensitivity of the electron multiplier ion detector to be the major reasons for the observed changes in overall OMS sensitivity. Weekly variations in sensitivity greater than 100% have been observed following system bakeout at 150 0 C and with the use of rhenium filaments which were initially in the QMS ionizer. Operation of the QMS systems with tungsten filaments and at constant temperature has yielded more stable operation with weekly sensitivity changes generally being less than 10%. 7 refs., 7 figs

Performance optimisation of a new-generation orthogonal-acceleration quadrupole-time-of-flight mass spectrometer.

Science.gov (United States)

Bristow, Tony; Constantine, Jill; Harrison, Mark; Cavoit, Fabien

2008-04-01

Orthogonal-acceleration quadrupole time-of-flight (oa-QTOF) mass spectrometers, employed for accurate mass measurement, have been commercially available for well over a decade. A limitation of the early instruments of this type was the narrow ion abundance range over which accurate mass measurements could be made with a high degree of certainty. Recently, a new generation of oa-QTOF mass spectrometers has been developed and these allow accurate mass measurements to be recorded over a much greater range of ion abundances. This development has resulted from new ion detection technology and improved electronic stability or by accurate control of the number of ions reaching the detector. In this report we describe the results from experiments performed to evaluate the mass measurement performance of the Bruker micrOTOF-Q, a member of the new-generation oa-QTOFs. The relationship between mass accuracy and ion abundance has been extensively evaluated and mass measurement accuracy remained stable (+/-1.5 m m/z units) over approximately 3-4 orders of magnitude of ion abundance. The second feature of the Bruker micrOTOF-Q that was evaluated was the SigmaFit function of the software. This isotope pattern-matching algorithm provides an exact numerical comparison of the theoretical and measured isotope patterns as an additional identification tool to accurate mass measurement. The smaller the value, the closer the match between theoretical and measured isotope patterns. This information is then employed to reduce the number of potential elemental formulae produced from the mass measurements. A relationship between the SigmaFit value and ion abundance has been established. The results from the study for both mass accuracy and SigmaFit were employed to define the performance criteria for the micrOTOF-Q. This provided increased confidence in the selection of elemental formulae resulting from accurate mass measurements.

Effect of ion entry acceptance conditions on the performance of a quadrupole mass spectrometer operated in upper and lower stability regions

International Nuclear Information System (INIS)

Turner, P.; Taylor, S.; Gibson, J.R.

2005-01-01

Computer simulation of ion motion in a quadrupole mass spectrometer has been used to examine the effect of initial ion conditions on performance when operated in the first and third zones of the Mathieu stability diagram. Commercial instruments frequently use round electrodes instead of the better-performing hyperbolic electrodes because the cost of manufacturing is lower. However, adverse features are seen when using round electrodes. Here further insight is provided and a possible method of correction is suggested. For the first time, ion origin for the first stability region for a round electrode quadrupole has been reported

Behaviour of quadrupole mass spectrometer towards noble gases

International Nuclear Information System (INIS)

Hasibullah

1980-01-01

This paper describes a quadrupole mass spectrometric set-up for noble gas analysis with its potential application to material accountancy at the input accountability tank of a reprocessing facility. Linear dependence of ion source pressure on the inlet pressure was considered to be practicable criterion for the functionality of the instrument. Short term and long term sensitivity variations have also been discussed. No memory effect was observed under the experimental conditions. (author)

SIMS device with quadrupole mass spectrometer

International Nuclear Information System (INIS)

Szigethy, D.; Riedel, M.

1980-01-01

A versatile secondary ion mass spectrometer (SIMS) has been designed and constructed. The device is applicable for dinamic and static SIMS investigations. The sputtering and ionisation can be studied simultaneously. Oil diffusion pumps and an auxiliary ion-getter pump are used. A commercial ion gun is used in the working chamber. The secondary ion optics assures the preliminary filtering of fast ions, and the collection of sputtered ions for a separate microprobe analysis. The performance of the apparatus is illustrated with examples. (R.J.)

Implementation of dipolar direct current (DDC) collision-induced dissociation in storage and transmission modes on a quadrupole/time-of-flight tandem mass spectrometer.

Science.gov (United States)

Webb, Ian K; Londry, Frank A; McLuckey, Scott A

2011-09-15

Means for effecting dipolar direct current collision-induced dissociation (DDC CID) on a quadrupole/time-of-flight in a mass spectrometer have been implemented for the broadband dissociation of a wide range of analyte ions. The DDC fragmentation method in electrodynamic storage and transmission devices provides a means for inducing fragmentation of ions over a large mass-to-charge range simultaneously. It can be effected within an ion storage step in a quadrupole collision cell that is operated as a linear ion trap or as ions are continuously transmitted through the collision cell. A DDC potential is applied across one pair of rods in the quadrupole collision cell of a QqTOF hybrid mass spectrometer to effect fragmentation. In this study, ions derived from a small drug molecule, a model peptide, a small protein, and an oligonucleotide were subjected to the DDC CID method in either an ion trapping or an ion transmission mode (or both). Several key experimental parameters that affect DDC CID results, such as time, voltage, low mass cutoff, and bath gas pressure, are illustrated with protonated leucine enkephalin. The DDC CID dissociation method gives a readily tunable, broadband tool for probing the primary structures of a wide range of analyte ions. The method provides an alternative to the narrow resonance conditions of conventional ion trap CID and it can access more extensive sequential fragmentation, depending upon conditions. The DDC CID approach constitutes a collision analog to infrared multiphoton dissociation (IRMPD). Copyright © 2011 John Wiley & Sons, Ltd.

RADIO-FREQUENCY MASS SPECTROMETERS AND THEIR APPLICATIONS IN SPACE

Energy Technology Data Exchange (ETDEWEB)

Gilmour, Jr., A. S.

1963-08-15

The operation of three common radio-frequency mass spectrometers is described, and their performances are compared. Their limitations are pointed out. It is concluded that the quadrupole spectrometer has fewer limitations and is more generally useful in space probes than the other devices. Some present and proposed uses of spectrometers in space are discussed, and the problem of contamination of the atmosphere being sampled by the spectrometer is reviewed. (auth)

Ultrasensitive leak detection during ultrahigh vacuum evacuation by quadrupole mass spectrometer

International Nuclear Information System (INIS)

Chen Xu; Huang Tianbin; Wang Ligong; Jin Qiji; Cha Liangzhen

2006-01-01

One must do ultrasensitive leak detection during ultrahigh-vacuum (UHV) evacuation, especially just before the device is sealed off from the vacuum system, to guarantee the longevity of the sealed high-vacuum or even UHV devices with small volume. A quadrupole mass spectrometer (QMS) with an UHV evacuation system can be used under accumulation mode to do the testing. Possible accumulate modes, as well as their advantages and shortcomings, are studied experimentally and discussed in this paper. We found that the opening action of the metal valve during accumulation mode always severely affects the height of the peak indicated by QMS and causes considerable errors. If we determine the leak rate by the peak area instead of the peak height, the situation is much improved. This method has proven quite useful in ensuring the tightness quality for complex sealed UHV devices with small volumes. Ultrasensitive leak detection has been carried out for such real evacuating devices, and a leak rate of 2x10 -14 Pa·m 3 /s was detected, which is far lower than its dynamic mode and the detection limit of the current advanced commercial leak detectors

Hydrogen isotope analysis by quadrupole mass spectrometry

International Nuclear Information System (INIS)

Ellefson, R.E.; Moddeman, W.E.; Dylla, H.F.

1981-03-01

The analysis of isotopes of hydrogen (H, D, T) and helium ( 3 He, 4 He) and selected impurities using a quadrupole mass spectrometer (QMS) has been investigated as a method of measuring the purity of tritium gas for injection into the Tokamak Fusion Test Reactor (TFTR). A QMS was used at low resolution, m/Δm 3 He, and 4 He in HT/D 2

High-throughput shotgun lipidomics by quadrupole time-of-flight mass spectrometry

DEFF Research Database (Denmark)

Ståhlman, Marcus; Ejsing, Christer S.; Tarasov, Kirill

2009-01-01

Technological advances in mass spectrometry and meticulous method development have produced several shotgun lipidomic approaches capable of characterizing lipid species by direct analysis of total lipid extracts. Shotgun lipidomics by hybrid quadrupole time-of-flight mass spectrometry allows...... the absolute quantification of hundreds of molecular glycerophospholipid species, glycerolipid species, sphingolipid species and sterol lipids. Future applications in clinical cohort studies demand detailed lipid molecule information and the application of high-throughput lipidomics platforms. In this review...... we describe a novel high-throughput shotgun lipidomic platform based on 96-well robot-assisted lipid extraction, automated sample infusion by mircofluidic-based nanoelectrospray ionization, and quantitative multiple precursor ion scanning analysis on a quadrupole time-of-flight mass spectrometer...

The calculus and the design of a miniature quadrupole mass filter: a selected solution from different types of mass analyzers

International Nuclear Information System (INIS)

Cuna, C.; Ioanoviciu, D.; Lupsa, N.; Chis, A.

2002-01-01

The mass spectrometers are very precise tools used in chemical and isotopic analysis for environmental surveillance. Traditionally environmental analysis is done by sampling the soil, air or water and taking the sample back to the laboratory for analysis. To avoid the difficulties related with the sample alteration during the sampling process and the transport the analysis 'in situ' is to be preferred. This type of analysis combines the sampling and analysis and produces an analytical result almost instantly. Fast-response detection methods are highly desirable in cases where relatively short-lived species are to be examined. Theoretically, any type of mass analyzers can be miniaturized, but some are better suited for miniaturization than others. We studied comparatively different types of mass analyzers that can be miniaturized, especially quadrupole, magnetic sector and time of flight types, in view to select from all these, the best solution for our purpose, the application to the 'in situ' environmental monitoring and inspection, analytical process control. We investigated and calculated the properties of some geometrical arrangements that we reported, one of these being a double focusing mass analyzer with electric deflector and magnetic deflector combined in a reversed geometry. From the different calculated versions we selected the following one, with the characteristic parameters: n = 62, f = 2 MHz, L = 0.07 m, r 0 = 2.616 x 10 -3 m, E z = 5 V, R housing = 3.5 r 0 , V m = 1000 V, R max = 200, M max = 200 u. Starting from these mechanical and electrical parameters we calculated and designed a miniature quadrupole mass spectrometer. A theoretical study of the ion trajectories in the quadrupole analyzer by matrix formalism as well as by using Mathieu functions was made. Using the program SIMION 6, the trajectories inside the quadrupole filter were also simulated. The calculus of the ion trajectories starts by numerically solving of the Mathieu type equation

Modification of an achromatic mass spectrometer to include transverse focusing

Energy Technology Data Exchange (ETDEWEB)

Baril, M; Noel, M

1987-08-15

Modification has been made to a magnetic mass spectrometer, comprising a magnetic prism and a parallel plane mirror, to increase its transmission and to obtain a stigmatic image. This has been done by adding two quadrupole lenses, one between the magnetic prism and the mirror to add some focusing in the transverse direction, the other after the mirror to correct the astigmatism created by the first quadrupole lens. In this paper, we derive all the parameters of the quadrupole lenses needed to ensure this objective.

Sensitive helium leak detection in a deuterium atmosphere using a high-resolution quadrupole mass spectrometer

International Nuclear Information System (INIS)

Hiroki, S.; Abe, T.; Murakami, Y.

1996-01-01

In fusion machines, realizing a high-purity plasma is a key to improving the plasma parameters. Thus, leak detection is a necessary part of reducing the leak rate to a tolerable level. However, a conventional helium ( 4 He) leak detector is useless in fusion machines with a deuterium (D 2 ) plasma, because retained D particles on the first walls release D 2 for a long period and the released D 2 interferes with the signals from the leaked 4 He due to the near identical masses of 4.0026 u ( 4 He) and 4.0282 u (D 2 ). A high-resolution quadrupole mass spectrometer (HR-QMS) that we have recently developed, can detect a 4 He + population as small as 10 -4 peak in a D 2 atmosphere. Thus, the HR-QMS has been applied to detect 4 He leaks. To improve the minimum detectable limit of 4 He leak, a differentially pumped HR-QMS analyzer was attached to a chamber of the 4 He leak detector. In conclusion, the improved 4 He leak detector could detect 4 He leaks of the order of 10 -10 Pa · m 3 /s in a D 2 atmosphere. (Author)

High-throughput analysis of amino acids in plant materials by single quadrupole mass spectrometry

DEFF Research Database (Denmark)

Dahl-Lassen, Rasmus; van Hecke, Jan Julien Josef; Jørgensen, Henning

2018-01-01

that it is very time consuming with typical chromatographic run times of 70 min or more. Results: We have here developed a high-throughput method for analysis of amino acid profiles in plant materials. The method combines classical protein hydrolysis and derivatization with fast separation by UHPLC and detection...... reducing the overall analytical costs compared to methods based on more advanced mass spectrometers....... by a single quadrupole (QDa) mass spectrometer. The chromatographic run time is reduced to 10 min and the precision, accuracy and sensitivity of the method are in line with other recent methods utilizing advanced and more expensive mass spectrometers. The sensitivity of the method is at least a factor 10...

Indigenous instrumentation for mass spectrometry: Part II - development of plasma source mass spectrometers. PD-5-3

International Nuclear Information System (INIS)

Nataraju, V.

2007-01-01

The growing demands from analytical community, for a precise isotope ratio and ultra trace concentration measurements, has lead to significant improvement in mass spectrometer instrumentation development with respect to sensitivity, detection limits, precision and accuracy. Among the many analytical techniques available, plasma source mass spectrometers like Inductively Coupled Plasma Mass Spectrometry (ICPMS), multi collector (MC) ICPMS and Glow Discharge Mass Spectrometry (GDMS), have matured into reliable tools for the above applications. Where as ICPMS is by far the most successful method for aqueous solutions, GDMS is being applied for bulk and impurity analysis of conducting as well non-conducting solids. VPID, BARC has been developing mass spectrometers for different inorganic applications of DAE users. Over the years expertise has been developed in all the aspects of mass spectrometry instrumentation. Part 1 of this indigenous instrumentation on mass spectrometry gives details of magnetic sector instruments with either EI or TI source for isotopic ratio analysis. The present paper is a continuation of that on plasma source and quadrupole mass spectrometers. This paper covers i) ICP-QMS, ii) MC-ICPMS, iii) GDMS and iv) QMS

Gas-phase ion-molecule reactions and high-pressure mass spectrometer, 1

International Nuclear Information System (INIS)

Hiraoka, Kenzo

1977-01-01

The reasons for the fact that the research in gas-phase ion-molecule reactions, to which wide interest is shown, have greatly contributed to the physical and chemical fields are that, first it is essential in understanding general phenomena concerning ions, second, it can furnish many unique informations in the dynamics of chemical reactions, and third, usefulness of '' chemical ionization'' methods has been established as its application to chemical analysis. In this review, the history and trend of studies and equipments in gas-phase ion-molecule reactions are surveyed. The survey includes the chemical ionization mass spectrometer for simultaneously measuring the positive and negative ions utilizing a quadrupole mass spectrometer presented by Hunt and others, flowing afterglow method derived from the flowing method which traces neutral chemical species mainly optically, ion cyclotron resonance mass spectrometer, trapped ion mass spectrometer and others. Number of reports referred to ion-molecule reactions issued during the last one year well exceeds the total number of reports concerning mass spectrometers presented before 1955. This truly shows how active the research and development are in this field. (Wakatsuki, Y.)

Ion trajectories quadrupole mass filters

International Nuclear Information System (INIS)

Ursu, D.; Lupsa, N.; Muntean, F.

1994-01-01

The present paper aims at bringing some contributions to the understanding of ion motion in quadrupole mass filters. The theoretical treatment of quadrupole mass filter is intended to be a concise derivation of the important physical relationships using Mathieu functions. A simple iterative method of numerical computation has been used to simulate ion trajectories in an ideal quadrupole field. Finally, some examples of calculation are presented with the aid of computer graphics. (Author) 14 Figs., 1 Tab., 20 Refs

Rapid Quadrupole-Time-of-Flight Mass Spectrometry Method Quantifies Oxygen-Rich Lignin Compound in Complex Mixtures

Science.gov (United States)

Boes, Kelsey S.; Roberts, Michael S.; Vinueza, Nelson R.

2018-03-01

Complex mixture analysis is a costly and time-consuming task facing researchers with foci as varied as food science and fuel analysis. When faced with the task of quantifying oxygen-rich bio-oil molecules in a complex diesel mixture, we asked whether complex mixtures could be qualitatively and quantitatively analyzed on a single mass spectrometer with mid-range resolving power without the use of lengthy separations. To answer this question, we developed and evaluated a quantitation method that eliminated chromatography steps and expanded the use of quadrupole-time-of-flight mass spectrometry from primarily qualitative to quantitative as well. To account for mixture complexity, the method employed an ionization dopant, targeted tandem mass spectrometry, and an internal standard. This combination of three techniques achieved reliable quantitation of oxygen-rich eugenol in diesel from 300 to 2500 ng/mL with sufficient linearity (R2 = 0.97 ± 0.01) and excellent accuracy (percent error = 0% ± 5). To understand the limitations of the method, it was compared to quantitation attained on a triple quadrupole mass spectrometer, the gold standard for quantitation. The triple quadrupole quantified eugenol from 50 to 2500 ng/mL with stronger linearity (R2 = 0.996 ± 0.003) than the quadrupole-time-of-flight and comparable accuracy (percent error = 4% ± 5). This demonstrates that a quadrupole-time-of-flight can be used for not only qualitative analysis but also targeted quantitation of oxygen-rich lignin molecules in complex mixtures without extensive sample preparation. The rapid and cost-effective method presented here offers new possibilities for bio-oil research, including: (1) allowing for bio-oil studies that demand repetitive analysis as process parameters are changed and (2) making this research accessible to more laboratories. [Figure not available: see fulltext.

Rapid determination of 18 glucocorticoids in serum using reusable on-line SPE polymeric monolithic column coupled with LC-quadrupole/orbitrap high-resolution mass spectrometer.

Science.gov (United States)

Li, Hui; Ai, Lianfeng; Fan, Sufang; Wang, Yan; Sun, Dianxing

2017-10-15

A simple, rapid and sensitive method for the simultaneous determination of 18 glucocorticoids in serum was developed by coupling on-line solid-phase extraction (SPE) polymeric monolithic column to a liquid chromatography-quadrupole/orbitrap high-resolution mass spectrometer. A simple poly(ethylene glycol dimethacrylate) monolith column (10mm×2.1mm i.d.) was fabricated, and the morphology, surface area and extraction performance of the monolithic column were characterized. Serum samples were extracted by acetonitrile (ACN). Then, online SPE was achieved on the synthesized monolithic column using a 10mmol/L ammonium acetate solution as the loading solvent. After the transfer from the monolith into analytical column (Capcell Pak ADME column) using ACN, the adsorbed analytes were separated on the analytical column and detected with a high-resolution hybrid quadrupole/orbitrap mass spectrometer with full scan/ddMS 2 scan mode Under optimized conditions, the method was linear with target linear correlation coefficient (R 2 ) higher than 0.995. Detection limits were in range of 0.1-0.6ng/mL, and the quantification limits were 0.3-1.5ng/mL. The recovery was between 71.9% and 89.2% in three spike levels with precision (n=5) of 5.40-12.1%. The serum sample was directly analyzed after a simple extraction procedure, and the on-line SPE and determination were achieved within only 16min. The method was used to analyze the dynamic contents variation of cortisone and hydrocortisone in serum before and after the surgery. Copyright © 2017 Elsevier B.V. All rights reserved.

Charged-particle magnetic-quadrupole spectrometer for neutron induced reactions

International Nuclear Information System (INIS)

Haight, R.C.; Grimes, S.M.; Tuckey, B.J.; Anderson, J.D.

1975-01-01

A spectrometer has been developed for measuring the charged particle production cross sections and spectra in neutron-induced reactions. The spectrometer consists of a magnetic quadrupole doublet which focuses the charged particles onto a silicon surface barrier detector telescope which is 2 meters or more from the irradiated sample. Collimators, shielding, and the large source-to-detector distance reduce the background enough to use the spectrometer with a 14-MeV neutron source producing 4 . 10 12 n/s. The spectrometer has been used in investigations of proton, deuteron, and alpha particle production by 14-MeV neutrons incident on various materials. Protons with energies as low as 1.1 MeV have been measured. The good resolution of the detectors has also made possible an improved measurement of the neutron- neutron scattering length from the 0 0 proton spectrum from deuteron breakup by 14-MeV neutrons

Ion-storage in radiofrequency electric quadrupole field

International Nuclear Information System (INIS)

Gheorghe, V.

1976-01-01

The confinement of charged particles in a quadrupole radiofrequency electric field are presented. The stability diagrams and phase space trajectories for the quadrupole mass spectrometer and for the ion trap are represented and their main characteristics are discussed. (author)

Transistor regenerative spectrometer for 14N nuclear quadrupole resonance study

International Nuclear Information System (INIS)

Anferov, V.P.; Mikhal'kov, V.M.

1981-01-01

Improvement of the Robinson transducer for investigations of nuclear quadrupole resonance (NQR) in 14 N is described. Amplifier of the suggested transducer is made using p-n field effect transistor and small-noise SHF bipolar transistor. Such a circuit permits to obtain optimal relation between input resistance, low-frequency noises and transconductance which provides uniform gain of the transducer in the frequency range of 0.6-12 MHz and permits to construct a transistor spectrometer of NQR not yielding to a lamp spectrometer in sensitivity [ru

Simultaneous ion detection in a mass spectrometer with variable mass dispersion

International Nuclear Information System (INIS)

Tuithof, H.H.

1977-01-01

This thesis mainly describes the ion-optics of a magnetic mass spectrometer system, especially applied to the projection of a significant part of the mass spectrum onto a flat ion-detector. The complete detector consists of a channeltron electron multiplier array with phosphor screen and a Vidicon-multichannel analyzer combination for simultaneous read-out. In order to optimise the spectral range projected onto the channelplate, by varying the mass dispersion and to rotate the oblique angle of the mass focal plane with respect to the detector surface, the sector magnet has been combined with electrostatic and magnetic quadrupole lenses. This detector will find wide application in the analysis of minute sample quantities, in the recording of extremely short ion events (large molecules) and at collision activation mass-spectrometry studies

Feasibility of coupling a thermal/optical carbon analyzer to a quadrupole mass spectrometer for enhanced PM2.5 speciation.

Science.gov (United States)

Riggio, Gustavo M; Chow, Judith C; Cropper, Paul M; Wang, Xiaoliang; Yatavelli, Reddy L N; Yang, Xufei; Watson, John G

2018-05-01

A thermal/optical carbon analyzer (TOA), normally used for quantification of organic carbon (OC) and elemental carbon (EC) in PM 2.5 (fine particulate matter) speciation networks, was adapted to direct thermally evolved gases to an electron impact quadrupole mass spectrometer (QMS), creating a TOA-QMS. This approach produces spectra similar to those obtained by the Aerodyne aerosol mass spectrometer (AMS), but the ratios of the mass to charge (m/z) signals differ and must be remeasured using laboratory-generated standards. Linear relationships are found between TOA-QMS signals and ammonium (NH 4 + ), nitrate (NO 3 - ), and sulfate (SO 4 2- ) standards. For ambient samples, however, positive deviations are found for SO 4 2- , compensated by negative deviations for NO 3 - , at higher concentrations. This indicates the utility of mixed-compound standards for calibration or separate calibration curves for low and high ion concentrations. The sum of the QMS signals across all m/z after removal of the NH 4 + , NO 3 - , and SO 4 2- signals was highly correlated with the carbon content of oxalic acid (C₂H₂O₄) standards. For ambient samples, the OC derived from the TOA-QMS method was the same as the OC derived from the standard IMPROVE_A TOA method. This method has the potential to reduce complexity and costs for speciation networks, especially for highly polluted urban areas such as those in Asia and Africa. Ammonium, nitrate, and sulfate can be quantified by the same thermal evolution analysis applied to organic and elemental carbon. This holds the potential to replace multiple parallel filter samples and separate laboratory analyses with a single filter and a single analysis to account for a large portion of the PM 2.5 mass concentration.

Novel control modes to improve the performance of rectilinear ion trap mass spectrometer with dual pressure chambers

Science.gov (United States)

Huo, Xinming; Tang, Fei; Zhang, Xiaohua; Chen, Jin; Zhang, Yan; Guo, Cheng'an; Wang, Xiaohao

2016-10-01

The rectilinear ion trap (RIT) has gradually become one of the preferred mass analyzers for portable mass spectrometers because of its simple configuration. In order to enhance the performance, including sensitivity, quantitation capability, throughput, and resolution, a novel RIT mass spectrometer with dual pressure chambers was designed and characterized. The studied system constituted a quadrupole linear ion trap (QLIT) in the first chamber and a RIT in the second chamber. Two control modes are hereby proposed: Storage Quadrupole Linear Ion Trap-Rectilinear Ion Trap (SQLIT-RIT) mode, in which the QLIT was used at high pressure for ion storage and isolation, and the RIT was used for analysis; and Analysis Quadrupole Linear Ion Trap-Rectilinear Ion Trap (AQLIT-RIT) mode, in which the QLIT was used for ion storage and cooling. Subsequently, synchronous scanning and analysis were carried out by QLIT and RIT. In SQLIT-RIT mode, signal intensity was improved by a factor of 30; the limit of quantitation was reduced more than tenfold to 50 ng mL-1, and an optimal duty cycle of 96.4% was achieved. In AQLIT-RIT mode, the number of ions coexisting in the RIT was reduced, which weakened the space-charge effect and reduced the mass shift. Furthermore, the mass resolution was enhanced by a factor of 3. The results indicate that the novel control modes achieve satisfactory performance without adding any system complexity, which provides a viable pathway to guarantee good analytical performance in miniaturization of the mass spectrometer.

A homemade high-resolution orthogonal-injection time-of-flight mass spectrometer with a heated capillary inlet

International Nuclear Information System (INIS)

Guo Changjuan; Huang Zhengxu; Gao Wei; Nian Huiqing; Chen Huayong; Dong Junguo; Shen Guoying; Fu Jiamo; Zhou Zhen

2008-01-01

We describe a homemade high-resolution orthogonal-injection time-of-flight (O-TOF) mass spectrometer combing a heated capillary inlet. The O-TOF uses a heated capillary tube combined with a radio-frequency only quadrupole (rf-only quadrupole) as an interface to help the ion transmission from the atmospheric pressure to the low-pressure regions. The principle, configuration of the O-TOF, and the performance of the instrument are introduced in this paper. With electrospray ion source, the performances of the mass resolution, the sensitivity, the mass range, and the mass accuracy are described. We also include our results obtained by coupling atmospheric pressure matrix-assisted laser deporption ionization with this instrument

A high efficiency thermal ionization source adapted to mass spectrometers

International Nuclear Information System (INIS)

Chamberlin, E.P.; Olivares, J.A.

1996-01-01

A tungsten crucible thermal ionization source mounted on a quadrupole mass spectrometer is described. The crucible is a disposable rod with a fine hole bored in one end; it is heated by electron bombardment. The schematic design of the assembly, including water cooling, is described and depicted. Historically, the design is derived from that of ion sources used on ion separators at Los Alamos and Dubna, but the crucible is made smaller and simplified. 10 refs., 4 figs

Studies on reducing the scale of a double focusing mass spectrometer

International Nuclear Information System (INIS)

Chambers, D.M.; Gregg, H.R.; Andresen, B.D.

1993-05-01

Several groups have developed miniaturized sector mass spectrometers with the goal of remote sensing in confined spaces or portability. However, these achievements have been overshadowed by more successful development of man-portable quadrupole and ion trap mass spectrometers. Despite these accomplishments the development of a reduced-scale sector mass spectrometer remains attractive as a potentially low-cost, robust instrument requiring very simple electronics and low power. Previous studies on miniaturizing sector instruments include the use of a Mattauch-Herzog design for a portable mass spectrograph weighing less than 10 kg. Other work has included the use of a Nier-Johnson design in spacecraft-mountable gas chromatography mass spectrometers for the Viking spacecraft as well as miniature sector-based MS/MS instrument. Although theory for designing an optimized system with high resolution and mass accuracy is well understood, such specifications have not yet been achieved in a miniaturized instrument. To proceed further toward the development of a miniaturized sector mass spectrometer, experiments were conducted to understand and optimize a practical, yet nonideal instrument configuration. The sector mass spectrometer studied in this work is similar to the ones developed for the Viking project, but was further modified to be low cost, simple and robust. Characteristics of this instrument that highlight its simplicity include the use of a modified Varian leak detector ion source, source ion optics that use one extraction voltage, and an unshunted fixed nonhomogeneous magnetic sector. The effects of these design simplifications on ion trajectory were studied by manipulating the ion beam along with the magnetic sector position. This latter feature served as an aid to study ion focusing amidst fringing fields as well as nonhomogeneous forces and permitted empirical realignment of the instrument

[Qualitative and quantitative analysis of amygdalin and its metabolite prunasin in plasma by ultra-high performance liquid chromatography-tandem quadrupole time of flight mass spectrometry and ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry].

Science.gov (United States)

Gao, Meng; Wang, Yuesheng; Wei, Huizhen; Ouyang, Hui; He, Mingzhen; Zeng, Lianqing; Shen, Fengyun; Guo, Qiang; Rao, Yi

2014-06-01

A method was developed for the determination of amygdalin and its metabolite prunasin in rat plasma after intragastric administration of Maxing shigan decoction. The analytes were identified by ultra-high performance liquid chromatography-tandem quadrupole time of flight mass spectrometry and quantitatively determined by ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry. After purified by liquid-liquid extraction, the qualitative analysis of amygdalin and prunasin in the plasma sample was performed on a Shim-pack XR-ODS III HPLC column (75 mm x 2.0 mm, 1.6 microm), using acetonitrile-0.1% (v/v) formic acid aqueous solution. The detection was performed on a Triple TOF 5600 quadrupole time of flight mass spectrometer. The quantitative analysis of amygdalin and prunasin in the plasma sample was performed by separation on an Agilent C18 HPLC column (50 mm x 2.1 mm, 1.7 microm), using acetonitrile-0.1% (v/v) formic acid aqueous solution. The detection was performed on an AB Q-TRAP 4500 triple quadrupole mass spectrometer utilizing electrospray ionization (ESI) interface operated in negative ion mode and multiple-reaction monitoring (MRM) mode. The qualitative analysis results showed that amygdalin and its metabolite prunasin were detected in the plasma sample. The quantitative analysis results showed that the linear range of amygdalin was 1.05-4 200 ng/mL with the correlation coefficient of 0.999 0 and the linear range of prunasin was 1.25-2 490 ng/mL with the correlation coefficient of 0.997 0. The method had a good precision with the relative standard deviations (RSDs) lower than 9.20% and the overall recoveries varied from 82.33% to 95.25%. The limits of detection (LODs) of amygdalin and prunasin were 0.50 ng/mL. With good reproducibility, the method is simple, fast and effective for the qualitative and quantitative analysis of the amygdalin and prunasin in plasma sample of rats which were administered by Maxing shigan decoction.

Application of artificial intelligence to triple quadrupole mass spectrometry (TQMS)

International Nuclear Information System (INIS)

Wong, C.M.; Crawford, R.W.; Kehler, T.P.; Kunz, J.C.

1984-01-01

At Lawrence Livermore National Laboratory the authors have designed a totally computerized triple quadrupole mass spectrometer with the ultimate goal of using it as a prototype for ''knowledge-based'' instrument control. As an ''intelligent'' instrument, with its computer-based data acquisition and control system, it has the ability to learn and respond quickly. The intelligence is encoded in the system using the representation and rule-based reasoning heuristic techniques of Artificial Intelligence. These techniques are used to encode heuristic knowledge, or the intuition, formal and informal rules, and experiential knowledge that the human expert normally uses to make decisions and arrive at solutions in a specific domain problem. In this specific case, the knowledge the authors are encoding is a tuning procedure for the spectrometer, including heuristics to describe a self-adaptive, feedback control process for real-time optimization or tuning of the data acquisition procedure throughout the entire data collection process

Mass measurements on radioactive isotopes using the ISOLTRAP spectrometer

CERN Document Server

Dilling, J; Kluge, H J; Kohl, A; Lamour, E; Marx, G; Schwarz, S C; Bollen, G; Kellerbauer, A G; Moore, R B; Henry, S

2000-01-01

ISOLTRAP is a Penning trap mass spectrometer installed at the on line isotope separator ISOLDE at CERN. Direct measurements of the masses of short lived radio isotopes are performed using the existing triple trap system. This consists of three electromagnetic traps in tandem: a Paul trap to accumulate and bunch the 60 keV dc beam, a Penning trap for cooling and isobar separation, and a precision Penning trap for the determination of the masses by cyclotron resonance. Measurements of masses of unknown mercury isotopes and in the vicinity of doubly magic /sup 208/Pb are presented, all with an accuracy of delta m/m approximately=1*10/sup -7/. Developments to replace the Paul trap by a radiofrequency quadrupole ion guide system to increase the collection efficiency are presently under way and the status is presented. (10 refs).

Recent Advances in Water Analysis with Gas Chromatograph Mass Spectrometers

Science.gov (United States)

MacAskill, John A.; Tsikata, Edem

2014-01-01

We report on progress made in developing a water sampling system for detection and analysis of volatile organic compounds in water with a gas chromatograph mass spectrometer (GCMS). Two approaches are described herein. The first approach uses a custom water pre-concentrator for performing trap and purge of VOCs from water. The second approach uses a custom micro-volume, split-splitless injector that is compatible with air and water. These water sampling systems will enable a single GC-based instrument to analyze air and water samples for VOC content. As reduced mass, volume, and power is crucial for long-duration, manned space-exploration, these water sampling systems will demonstrate the ability of a GCMS to monitor both air and water quality of the astronaut environment, thereby reducing the amount of required instrumentation for long duration habitation. Laboratory prototypes of these water sampling systems have been constructed and tested with a quadrupole ion trap mass spectrometer as well as a thermal conductivity detector. Presented herein are details of these water sampling system with preliminary test results.

High-Precision Mass Measurements of Exotic Nuclei with the Triple-Trap Mass Spectrometer Isoltrap

CERN Multimedia

Blaum, K; Zuber, K T; Stanja, J

2002-01-01

The masses of close to 200 short-lived nuclides have already been measured with the mass spectrometer ISOLTRAP with a relative precision between 1$\\times$10$^{-7}$ and 1$\\times$10^{-8}$. The installatin of a radio-frequency quadrupole trap increased the overall efficiency by two orders of magnitude which is at present about 1%. In a recent upgrade, we installed a carbon cluster laser ion source, which will allow us to use carbon clusters as mass references for absolute mass measurements. Due to these improvements and the high reliability of ISOLTRAP we are now able to perform accurate high-precision mass measurements all over the nuclear chart. We propose therefore mass measurements on light, medium and heavy nuclides on both sides of the valley of stability in the coming four years. ISOLTRAP is presently the only instrument capable of the high precision required for many of the proposed studies.

Performance and application of a fourfold monopole mass spectrometer

International Nuclear Information System (INIS)

Richards, J.A.; Huey, R.M.

1978-01-01

Some preliminary tests with an experimental fourfold monopole mass spectrometer described, illustrating that the device performs acceptably (at the low resolutions used) despite the fact that the field-forming surfaces of the driven electrodes are only one quadrant of a cylinder. Coupling between adjacent channels is shown not to be a problem so that applications requiring simultaneous measurements using two or more of the monopole channels can be entertained. Owing to its parellel structure the instrument is suggested as being suited particularly to isotope ratio measurements with precisions which could be significantly better than would be possible with a quadrupole device. (Auth.)

Scanning mass spectrometer setup for spatially resolved reactivity studies on model catalysts

Energy Technology Data Exchange (ETDEWEB)

Roos, Matthias; Schirling, Christian; Kielbassa, Stefan; Bansmann, Joachim; Behm, Juergen [Institut fuer Oberflaechenchemie und Katalyse, Universitaet Ulm, D-89069 Ulm (Germany)

2007-07-01

A scanning mass spectrometer with micrometer-scale resolution was developed for investigations on the catalytic activity of microstructured planar model catalysts. Products of local surface reactions can be detected via a fine capillary orifice in a differentially pumped quadrupole mass spectrometer. The position of the sample with respect to the capillary is controlled by three piezo-driven translators. The surface reactivity of a resistive heated sample can be depicted in a spatially resolved topogram, taking into account the influence of the distance between sample and capillary on the magnitude of the QMS signal and the lateral resolution. Photolithographic structured reactive patterns on top of an inactive substrate enable investigations of mesoscopic transport effects such as coupling between catalytically active areas and of (reverse) spillover phenomena on one sample by varying the size and the distances of the active areas.

Optimization of the isotopic analysis of UF6 by quadrupole mass spectrometry technique

International Nuclear Information System (INIS)

Porto, Peterson

2006-01-01

In the present work a procedure for determination of the isotopic ratio 238 U/ 235 U in UF 6 samples was established using a quadrupole mass spectrometer with ionization by electron impact and ion detection by Faraday cup or electron multiplier. For this, the following items were optimized in the spectrometer: the parameters in the ion source that provided the most intense peak, with good shape, for the corresponding mass of the most abundant isotope; the resolution that reduced the non linear effects and the number of analytic cycles that reduced the uncertainty in the results. The measurement process was characterized with respect to the effects of mass discrimination, linearity and memory effect. The mass discrimination showed to be linearly dependent of the sample pressure in the batch volume, for the pressure ranges from 0.15 to 0.30 mbar and from 0.30 to 0.40 mbar. The spectrometer was shown linear in the measurement of isotopic ratios between 0.005 and 0.045. The memory factor for the ion source and for the introduction system were, respectively, 1.000 ± 0.001 and 1.003 ± 0.003; the first one can be ignored, the second one can be eliminated by washing the batch volume with the new sample. A methodology for routine analysis of UF 6 samples and the determination of the uncertainties were set up in details as well. (author)

An integrated ion trap and time-of-flight mass spectrometer for chemical and photo- reaction dynamics studies

International Nuclear Information System (INIS)

Schowalter, Steven J.; Chen Kuang; Rellergert, Wade G.; Sullivan, Scott T.; Hudson, Eric R.

2012-01-01

We demonstrate the integration of a linear quadrupole trap with a simple time-of-flight mass spectrometer with medium-mass resolution (m/Δm∼ 50) geared towards the demands of atomic, molecular, and chemical physics experiments. By utilizing a novel radial ion extraction scheme from the linear quadrupole trap into the mass analyzer, a device with large trap capacity and high optical access is realized without sacrificing mass resolution. This provides the ability to address trapped ions with laser light and facilitates interactions with neutral background gases prior to analyzing the trapped ions. Here, we describe the construction and implementation of the device as well as present representative ToF spectra. We conclude by demonstrating the flexibility of the device with proof-of-principle experiments that include the observation of molecular-ion photodissociation and the measurement of trapped-ion chemical reaction rates.

Chemical characterization of microparticles by laser ablation in an ion trap mass spectrometer

International Nuclear Information System (INIS)

Dale, J.M.; Whitten, W.B.; Ramsey, J.M.

1991-01-01

We are developing a new technique for the chemical characterization of microparticles based upon the use of electrodynamic traps. The electrodynamic trap has achieved widespread use in the mass spectrometry community in the form of the ion trap mass spectrometer or quadrupole ion trap. Small macroscopic particles can be confined or levitated within the electrode structure of a three-dimensional quadrupole electrodynamic trap in the same way as fundamental charges or molecular ions by using a combination of ac and dc potentials. Our concept is to use the same electrode structure to perform both microparticle levitation and ion trapping/mass analysis. The microparticle will first be trapped and spatially stabilized within the trap for characterization by optical probes, i.e., absorption, fluorescence, or Raman spectroscopy. After the particle has been optically characterized, it is further characterized using mass spectrometry. Ions are generated from the particle surface using laser ablation or desorption. The characteristics of the applied voltages are changed to trap the ions formed by the laser with the ions subsequently mass analyzed. The work described in this paper focuses on the ability to perform laser desorption experiments on microparticles contained within the ion trap

Quadrupole Time-of-Flight Mass Spectrometer

Data.gov (United States)

Federal Laboratory Consortium — FUNCTION: The system generates superior quality mass spectrometry (MS) and tandem mass spectrometry (MS/MS) data from both atmospheric pressure ionization (API) and...

Acquisition of HPLC-Mass Spectrometer

Science.gov (United States)

2015-08-18

31-Jan-2015 Approved for Public Release; Distribution Unlimited Final Report: Acquisition of HPLC -Mass Spectrometer The views, opinions and/or findings...published in peer-reviewed journals: Final Report: Acquisition of HPLC -Mass Spectrometer Report Title The acquisition of the mass spectrometer has been a

Atom-probe field-ion-microscope mass spectrometer

International Nuclear Information System (INIS)

Nishikawa, Osamu

1983-01-01

The titled analyzer, called simply atom-probe, has been developed by combining a field ion microscope (FIM) and a mass spectrometer, and is divided into the time-of-flight type, magnetic sector type, and quadrupole type depending on the types of mass spectrometers. In this paper, the author first describes on the principle and construction of a high resolution, time-of-flight atom-probe developed and fabricated in his laboratory. The feature of the atom-probe lies in the analysis of atoms and molecules in hyper-fine structure region one by one utilizing the high resolution of FIM. It also has the advantages of directly determining the composition by a ratio of the numbers of respective ions because of a constant detection sensitivity regardless of mass numbers, of the resolution as high as single atom layer in depth direction, and of detecting the positional relationship among detected ions by the order of detection in a sample. To determine the composition in a hyperfine structure region, the limited small number of atoms and molecules in the region must be identified distinctly one by one. In the analyzed result of Ni-silicide formed by heating Si evaporated on a Ni tip at 1000 K for 5 minutes, each isotope was not only clearly separated, but also their abundance ratio was very close to the natural abundance ratio. The second half of the paper reports on the analysis of TiC promising for a cold cathode material, adsorption of CO and alcohol, and the composition and structure of silicides, as a few application examples. (Wakatsuki, Y.)

An integrated ion trap and time-of-flight mass spectrometer for chemical and photo- reaction dynamics studies.

Science.gov (United States)

Schowalter, Steven J; Chen, Kuang; Rellergert, Wade G; Sullivan, Scott T; Hudson, Eric R

2012-04-01

We demonstrate the integration of a linear quadrupole trap with a simple time-of-flight mass spectrometer with medium-mass resolution (m/Δm ∼ 50) geared towards the demands of atomic, molecular, and chemical physics experiments. By utilizing a novel radial ion extraction scheme from the linear quadrupole trap into the mass analyzer, a device with large trap capacity and high optical access is realized without sacrificing mass resolution. This provides the ability to address trapped ions with laser light and facilitates interactions with neutral background gases prior to analyzing the trapped ions. Here, we describe the construction and implementation of the device as well as present representative ToF spectra. We conclude by demonstrating the flexibility of the device with proof-of-principle experiments that include the observation of molecular-ion photodissociation and the measurement of trapped-ion chemical reaction rates. © 2012 American Institute of Physics

DC superconducting quantum interference device usable in nuclear quadrupole resonance and zero field nuclear magnetic spectrometers

Science.gov (United States)

Fan, Non Q.; Clarke, John

1993-01-01

A spectrometer for measuring the nuclear quadrupole resonance spectra or the zero-field nuclear magnetic resonance spectra generated by a sample is disclosed. The spectrometer uses an amplifier having a dc SQUID operating in a flux-locked loop for generating an amplified output as a function of the intensity of the signal generated by the sample. The flux-locked loop circuit includes an integrator. The amplifier also includes means for preventing the integrator from being driven into saturation. As a result, the time for the flux-locked loop to recover from the excitation pulses generated by the spectrometer is reduced.

Applicability of hybrid linear ion trap-high resolution mass spectrometry and quadrupole-linear ion trap-mass spectrometry for mycotoxin analysis in baby food.

Science.gov (United States)

Rubert, Josep; James, Kevin J; Mañes, Jordi; Soler, Carla

2012-02-03

Recent developments in mass spectrometers have created a paradoxical situation; different mass spectrometers are available, each of them with their specific strengths and drawbacks. Hybrid instruments try to unify several advantages in one instrument. In this study two of wide-used hybrid instruments were compared: hybrid quadrupole-linear ion trap-mass spectrometry (QTRAP®) and the hybrid linear ion trap-high resolution mass spectrometry (LTQ-Orbitrap®). Both instruments were applied to detect the presence of 18 selected mycotoxins in baby food. Analytical parameters were validated according to 2002/657/CE. Limits of quantification (LOQs) obtained by QTRAP® instrument ranged from 0.45 to 45 μg kg⁻¹ while lower limits of quantification (LLOQs) values were obtained by LTQ-Orbitrap®: 7-70 μg kg⁻¹. The correlation coefficients (r) in both cases were upper than 0.989. These values highlighted that both instruments were complementary for the analysis of mycotoxin in baby food; while QTRAP® reached best sensitivity and selectivity, LTQ-Orbitrap® allowed the identification of non-target and unknowns compounds. Copyright © 2011 Elsevier B.V. All rights reserved.

Determination of the isotopic ratio 235U/238U in UF6 using quadrupole mass spectrometry

International Nuclear Information System (INIS)

Kusahara, Helena Sueco

1979-01-01

In this work measurements of isotope ratios 235 U / 23 '8U in uranium hexafluoride are carried out using a quadrupole mass spectrometer. The operational parameters, which affect the final precision of the results, are standardized. Optimized procedures for the preparation of uranium hexafluoride samples by fluorination of uranium oxides using cobalt trifluoride method are established. Careful attention is given to the process of purification of uranium hexafluoride samples by fractional distillation. Adequate statistical methods for analysing the results obtained for single ratio measurements as well as the ratio ' of isotopic ratios of sample and standard ar.e developed. A precision of about 10 -4 for single ratio measurements and accuracy of about 0,3% for the ratio of sample and standard ratios are obtained. These results agree with the values which have been obtained using magnetic mass spectrometers. The procedures and methods established in this work can be employed in the systematic uranium isotope analysis in UF 6 form. (author)

Mass spectrometers in medicine

International Nuclear Information System (INIS)

Bushman, J.A.

1975-01-01

This paper describes how the mass spectrometer enables true lung function, namely the exchange of gases between the environment and the organism, to be measured. This has greatly improved the understanding of respiratory disease and the latest generation of respiratory mass spectrometers will do much to increase the application of the technique. (author)

Inductively coupled plasma mass spectrometry with a twin quadrupole instrument using laser ablation sample introduction and monodisperse dried microparticulate injection

Energy Technology Data Exchange (ETDEWEB)

Allen, Lloyd A. [Iowa State Univ., Ames, IA (United States)

1996-10-17

The focus of this dissertation is the use of a twin quadrupole inductively coupled plasma mass spectrometer (ICP-MS) for the simultaneous detection of two m/z values. The twin quadrupole ICP-MS is used with laser ablation sample introduction in both the steady state (10 Hz) and single pulse modes. Steady state signals are highly correlated and the majority of flicker noise cancels when the ratio is calculated. Using a copper sample, the isotope ratio ⁶³Cu⁺/⁶⁵Cu⁺ is measured with a relative standard deviation (RSD) of 0.26%. Transient signals for single laser pulses are also obtained. Copper isotope ratio measurements for several laser pulses are measured with an RSD of 0.85%. Laser ablation (LA) is used with steel samples to assess the ability of the twin quadrupole ICP-MS to eliminate flicker noise of minor components of steel samples. Isotopic and internal standard ratios are measured in the first part of this work. The isotope ratio ⁵²Cr⁺/⁵³Cr⁺ (Cr present at 1.31 %) can be measured with an RSD of 0.06 % to 0.1 %. For internal standard elements, RSDs improve from 1.9 % in the Cr⁺ signal to 0.12% for the ratio of ⁵¹V⁺ to ⁵²Cr⁺. In the second part of this work, one mass spectrometer is scanned while the second channel measures an individual m/z value. When the ratio of these two signals is calculated, the peak shapes in the mass spectrum are improved significantly. Pulses of analyte and matrix ions from individual drops are measured simultaneously using the twin quadrupole ICP-MS with monodisperse dried microparticulate injection (MDMI). At modest Pb concentrations (500 ppm), a shoulder on the leading edge of the Li⁺ signal becomes apparent. Space charge effects are consistent with the disturbances seen.

Comprehensive analysis of a multidimensional liquid chromatography mass spectrometry dataset acquired on a quadrupole selecting, quadrupole collision cell, time-of-flight mass spectrometer: I. How much of the data is theoretically interpretable by search engines?

Science.gov (United States)

Chalkley, Robert J; Baker, Peter R; Hansen, Kirk C; Medzihradszky, Katalin F; Allen, Nadia P; Rexach, Michael; Burlingame, Alma L

2005-08-01

An in-depth analysis of a multidimensional chromatography-mass spectrometry dataset acquired on a quadrupole selecting, quadrupole collision cell, time-of-flight (QqTOF) geometry instrument was carried out. A total of 3269 CID spectra were acquired. Through manual verification of database search results and de novo interpretation of spectra 2368 spectra could be confidently determined as predicted tryptic peptides. A detailed analysis of the non-matching spectra was also carried out, highlighting what the non-matching spectra in a database search typically are composed of. The results of this comprehensive dataset study demonstrate that QqTOF instruments produce information-rich data of which a high percentage of the data is readily interpretable.

Software for mass spectrometer control

International Nuclear Information System (INIS)

Curuia, Marian; Culcer, Mihai; Anghel, Mihai; Iliescu, Mariana; Trancota, Dan; Kaucsar, Martin; Oprea, Cristiana

2004-01-01

The paper describes a software application for the MAT 250 mass spectrometer control, which was refurbished. The spectrometer was bring-up-to-date using a hardware structure on its support where the software application for mass spectrometer control was developed . The software application is composed of dedicated modules that perform given operations. The instructions that these modules have to perform are generated by a principal module. This module makes possible the change of information between the modules that compose the software application. The use of a modal structure is useful for adding new functions in the future. The developed application in our institute made possible the transformation of the mass spectrometer MAT 250 into a device endowed with other new generation tools. (authors)

Recent ion optics and mass spectrometers

International Nuclear Information System (INIS)

Matsuda, Hisashi

1976-01-01

The establishment of the third order approximation method for computing the orbit of the ion optical system for mass spectrometers and the completion of its computer program are reported. A feature of this orbit computation is in that the effect of the fringing field can be considered with the accuracy of third order approximation. Several new ion optical systems for mass spectrometers have been proposed by using such orbit computing programs. Brief explanation and the description on the future prospect and problems are made on the following items: the vertual image double focusing mass spectrometer, the second order double focusing mass spectrometer, the E x B superposed field mass spectrometer, and the apparatus with a cylindrical electric field and Q-lens. In the E x B superposed field with Matsuda plates, if the magnetic field is generated by an electromagnet instead of a permanent magnet, the dispersion of mass and energy can be changed at will. The Matsuda plates are known as the auxiliary electrodes positioned at the top and bottom of a cylindrical capacitor. Utilizing those characteristics, a zoom spectrometer can be made, with which only a necessary part of mass spectra can be investigated in detail, but the whole spectra are investigated roughly. In addition, the distribution of energy can be investigated simultaneously after the separation of ionic mass similarly to the parabola apparatus. (Iwakiri, K.)

Ion beam properties after mass filtering with a linear radiofrequency quadrupole

International Nuclear Information System (INIS)

Ferrer, R.; Kwiatkowski, A.A.; Bollen, G.; Lincoln, D.L.; Morrissey, D.J.; Pang, G.K.; Ringle, R.; Savory, J.; Schwarz, S.

2014-01-01

The properties of ion beams passing through a linear radiofrequency quadrupole mass filter were investigated with special attention to their dependence on the mass resolving power. Experimentally, an increase of the transverse emittance was observed as the mass-to-charge selectivity of the mass filter was raised. The experimental behavior was confirmed by beam transport simulations. -- Highlights: • The ion-optical properties of a Quadrupole Mass Filter (QMF) are presented. • Measured beam emittances follow a trend to larger values for smaller A/Q ratios and increasing mass resolution. • The experimental behavior was confirmed by beam transport simulations. • The use of a QMF for mass filtering comes at the cost of emittance growth of the ion beam

Mini ion trap mass spectrometer

Science.gov (United States)

Dietrich, D.D.; Keville, R.F.

1995-09-19

An ion trap is described which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10{sup 9} and commercial mass spectrometers requiring 10{sup 4} ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products. 10 figs.

Use of microextraction by packed sorbent directly coupled to an electron ionization single quadrupole mass spectrometer as an alternative for non-separative determinations.

Science.gov (United States)

Casas Ferreira, Ana María; Moreno Cordero, Bernardo; Pérez Pavón, José Luis

2017-02-01

Sometimes it is not necessary to separate the individual compounds of a sample to resolve an analytical problem, it is enough to obtain a signal profile of the sample formed by all the components integrating it. Within this strategy, electronic noses based on the direct coupling of a headspace sampler with a mass spectrometer (HS-MS) have been proposed. Nevertheless, this coupling is not suitable for the analysis of non-volatile compounds. In order to propose an alternative to HS-MS determinations for non-volatile compounds, here we present the first 'proof of concept' use of the direct coupling of microextraction by packed sorbents (MEPS) to a mass spectrometer device using an electron ionization (EI) and a single quadrupole as ionization source and analyzer, respectively. As target compounds, a set of analytes with different physic-chemical properties were evaluated (2-ethyl-1-hexanol, styrene, 2-heptanone, among others). The use of MEPS extraction present many advantages, such as it is fast, simple, easy to automate and requires small volumes of sample and organic solvents. Moreover, MEPS cartridges are re-usable as samples can be extracted more than 100 times using the same syringe. In order to introduce into the system all the elution volume from the MEPS extraction, a programmable temperature vaporizer (PTV) is proposed as the injector device. Results obtained with the proposed methodology (MEPS-PTV/MS) were compared with the ones obtained based on the separative scheme, i.e. using gas chromatography separation (MEPS-PTV-GC/MS), and both methods provided similar results. Limits of detection were found to be between 3.26 and 146.6μgL -1 in the non-separative scheme and between 0.02 and 1.72μgL -1 when the separative methodology was used. Repeatability and reproducibility were evaluated with values below 17% in all cases. Copyright © 2016 Elsevier B.V. All rights reserved.

Gas-dust-impact mass spectrometer

CERN Document Server

Semkin, N D; Myasnikov, S V; Pomelnikov, R A

2002-01-01

Paper describes design of a mass spectrometer to study element composition of micro meteorite and man-made particles in space. Paper describes a way to improve resolution of mass spectrometer based on variation of parameters of accelerating electric field in time. The advantage of the given design of mass spectrometer in comparison with similar ones is its large operating area and higher resolution at the comparable weight and dimensions. Application of a combined design both for particles and for gas enables to remove space vehicle degassing products from the spectrum and, thus, to improve reliability of the acquired information, as well as, to acquire information on a gas component of the external atmosphere of a space vehicle

Aerosol quantification with the Aerodyne Aerosol Mass Spectrometer: detection limits and ionizer background effects

Directory of Open Access Journals (Sweden)

S. Borrmann

2009-02-01

Full Text Available Systematic laboratory experiments were performed to investigate quantification of various species with two versions of the Aerodyne Aerosol Mass Spectrometer, a Quadrupole Aerosol Mass Spectrometer (Q-AMS and a compact Time-of-Flight Aerosol Mass Spectrometer (c-ToF-AMS. Here we present a new method to continuously determine the detection limits of the AMS analyzers during regular measurements, yielding detection limit (DL information under various measurement conditions. Minimum detection limits range from 0.03 μg m⁻³ (nitrate, sulfate, and chloride up to 0.5 μg m⁻³ (organics for the Q-AMS. Those of the c-ToF-AMS are found between 0.003 μg m⁻³ (nitrate, sulfate and 0.03 μg m⁻³ (ammonium, organics. The DL values found for the c-ToF-AMS were ~10 times lower than those of the Q-AMS, mainly due to differences in ion duty cycle. Effects causing an increase of the detection limits include long-term instrument contamination, measurement of high aerosol mass concentrations and short-term instrument history. The self-cleaning processes which reduce the instrument background after measurement of large aerosol concentrations as well as the influences of increased instrument background on mass concentration measurements are discussed. Finally, improvement of detection limits by extension of averaging time intervals, selected or reduced ion monitoring, and variation of particle-to-background measurement ratio are investigated.

Multiple and sequential data acquisition method: an improved method for fragmentation and detection of cross-linked peptides on a hybrid linear trap quadrupole Orbitrap Velos mass spectrometer.

Science.gov (United States)

Rudashevskaya, Elena L; Breitwieser, Florian P; Huber, Marie L; Colinge, Jacques; Müller, André C; Bennett, Keiryn L

2013-02-05

The identification and validation of cross-linked peptides by mass spectrometry remains a daunting challenge for protein-protein cross-linking approaches when investigating protein interactions. This includes the fragmentation of cross-linked peptides in the mass spectrometer per se and following database searching, the matching of the molecular masses of the fragment ions to the correct cross-linked peptides. The hybrid linear trap quadrupole (LTQ) Orbitrap Velos combines the speed of the tandem mass spectrometry (MS/MS) duty circle with high mass accuracy, and these features were utilized in the current study to substantially improve the confidence in the identification of cross-linked peptides. An MS/MS method termed multiple and sequential data acquisition method (MSDAM) was developed. Preliminary optimization of the MS/MS settings was performed with a synthetic peptide (TP1) cross-linked with bis[sulfosuccinimidyl] suberate (BS(3)). On the basis of these results, MSDAM was created and assessed on the BS(3)-cross-linked bovine serum albumin (BSA) homodimer. MSDAM applies a series of multiple sequential fragmentation events with a range of different normalized collision energies (NCE) to the same precursor ion. The combination of a series of NCE enabled a considerable improvement in the quality of the fragmentation spectra for cross-linked peptides, and ultimately aided in the identification of the sequences of the cross-linked peptides. Concurrently, MSDAM provides confirmatory evidence from the formation of reporter ions fragments, which reduces the false positive rate of incorrectly assigned cross-linked peptides.

Charged particle scintillation mass spectrometer

International Nuclear Information System (INIS)

Baranov, P.S.; Zhuravlev, E.E.; Nafikov, A.A.; Osadchi , A.I.; Raevskij, V.G.; Smirnov, P.A.; Cherepnya, S.N.; Yanulis, Yu.P.

1982-01-01

A scintillation mass-spectrometer for charged particle identification by the measured values of time-of-flight and energy operating on line with the D-116 computer is described. Original time detectors with 100x100x2 mm 3 and 200x2 mm 2 scintillators located on the 1- or 2 m path length are used in the spectrometer. The 200x200x200 mm 3 scintillation unit is used as a E-counter. Time-of-flight spectra of the detected particles on the 2 m path length obtained in spectrometer test in the beam of charged particles escaping from the carbon target at the angle of 130 deg under 1.2 GeV bremsstrahlung beam of the ''Pakhra'' PIAS synchrotron are presented. Proton and deuteron energy spectra as well as mass spectrum of all the particles detected by the spectrometer are given. Mass resolution obtained on the 2 m path length for π-mesons is +-25%, for protons is +-5%, for deuterons is +-3%

Introduction of a 20 kHz Nd:YVO4 laser into a hybrid quadrupole time-of-flight mass spectrometer for MALDI-MS imaging.

Science.gov (United States)

Trim, Paul J; Djidja, Marie-Claude; Atkinson, Sally J; Oakes, Keith; Cole, Laura M; Anderson, David M G; Hart, Philippa J; Francese, Simona; Clench, Malcolm R

2010-08-01

A commercial hybrid quadrupole time-of-flight mass spectrometer has been modified for high-speed matrix-assisted laser desorption ionisation (MALDI) imaging using a short-pulse optical technology Nd:YVO(4) laser. The laser operating in frequency-tripled mode (lambda = 355 nm) is capable of delivering 1.5-ns pulses of energy at up to 8 microJ at 5-10 kHz and 3 microJ at 20 kHz. Experiments to improve beam homogeneity and reduce laser speckle by mechanical vibration of the fibre-optic laser delivery system are reported along with data from trial and tissue imaging experiments using the modified instrument. The laser appeared to yield best results for MALDI-MS imaging experiments when operating at repetition rates 5-10 kHz. Combining this with raster imaging allowed images of rat brain sections to be recorded in 37 min. Similarly, images of the distribution of peptides in "on-tissue" digest experiments from tumour tissues were recorded in 1 h and 30 min rather than the 8-h acquisition time previously used. A brief investigation of targeted protein analysis/imaging by multiple reaction monitoring experiments "on-tissue" is reported. A total of 26 transitions were recorded over a 3-s cycle time and images of abundant proteins were successfully recorded.

A molecular beam/quadrupole mass spectrometer system with synchronized beam modulation and digital waveform analysis

Science.gov (United States)

Pellett, G. L.; Adams, B. R.

1983-01-01

A performance evaluation is conducted for a molecular beam/mass spectrometer (MB/MS) system, as applied to a 1-30 torr microwave-discharge flow reactor (MWFR) used in the formation of the methylperoxy radical and a study of its subsequent destruction in the presence or absence of NO(x). The modulated MB/MS system is four-staged and differentially pumped. The results obtained by the MWFR study is illustrative of overall system performance, including digital waveform analysis; significant improvements over previous designs are noted in attainable S/N ratio, detection limit, and accuracy.

Use of liquid chromatography hybrid triple-quadrupole mass spectrometry for the detection of emodin metabolites in rat bile and urine.

Science.gov (United States)

Wu, Songyan; Zhang, Yaqing; Zhang, Zunjian; Song, Rui

2017-10-01

Emodin is the representative form of rhubarb, which is widely used in traditional Chinese medicine for the treatment of purgative, anti-inflammatory, antioxidative and antiviral, etc. Previous reports demonstrated that emodin glucuronide was the major metabolite in plasma. Owing to the extensive conjugation reactions of polyphenols, the aim of this study was to identify the metabolites of emodin in rat bile and urine. Neutral loss and precursor ion scan methods of triple-quadrupole mass spectrometer revealed 13 conjugated metabolites in rat bile and 22 metabolites in rat urine, which included four phase I and 18 phase II metabolites. The major metabolites in rat biosamples were emodin glucuronoconjugates. Moreover, rhein monoglucuronide, chrysophanol monoglucuronide and rhein sulfate were proposed for the first time after oral administration of emodin. Overall, liquid chromatography hybrid triple-quadrupole mass spectrometry analysis leads to the discovery of several novel emodin metabolites in rat bile and urine and underscores that conjugated with glucuronic acid is the main metabolic pathway. Copyright © 2017 John Wiley & Sons, Ltd.

Ion mobility spectrometer / mass spectrometer (IMS-MS).

Energy Technology Data Exchange (ETDEWEB)

Hunka Deborah Elaine; Austin, Daniel E.

2005-07-01

The use of Ion Mobility Spectrometry (IMS) in the Detection of Contraband Sandia researchers use ion mobility spectrometers for trace chemical detection and analysis in a variety of projects and applications. Products developed in recent years based on IMS-technology include explosives detection personnel portals, the Material Area Access (MAA) checkpoint of the future, an explosives detection vehicle portal, hand-held detection systems such as the Hound and Hound II (all 6400), micro-IMS sensors (1700), ordnance detection (2500), and Fourier Transform IMS technology (8700). The emphasis to date has been on explosives detection, but the detection of chemical agents has also been pursued (8100 and 6400). Combining Ion Mobility Spectrometry (IMS) with Mass Spectrometry (MS) is described. The IMS-MS combination overcomes several limitations present in simple IMS systems. Ion mobility alone is insufficient to identify an unknown chemical agent. Collision cross section, upon which mobility is based, is not sufficiently unique or predictable a priori to be able to make a confident peak assignment unless the compounds present are already identified. Molecular mass, on the other hand, is much more readily interpreted and related to compounds. For a given compound, the molecular mass can be determined using a pocket calculator (or in one's head) while a reasonable value of the cross-section might require hours of computation time. Thus a mass spectrum provides chemical specificity and identity not accessible in the mobility spectrum alone. In addition, several advanced mass spectrometric methods, such as tandem MS, have been extensively developed for the purpose of molecular identification. With an appropriate mass spectrometer connected to an ion mobility spectrometer, these advanced identification methods become available, providing greater characterization capability.

Quadrupole magnetic mapping of the high resolution spectrometers of Thomas Jefferson National Accelerator Laboratory, Hall A. (Q.M.M. project: Quadrupole Magnetic Measurement)

International Nuclear Information System (INIS)

Quemener, Gilles

1997-01-01

This thesis describes the magnetic measurements that have been performed on the superconducting quadrupoles of the High Resolution Spectrometers of TJNAF, Hall A (USA), which are designed to measure particle momentum up to 4 GeV.c -1 with a σp/p = 10 -4 resolution. The mapping method is based on rotating coil technique, the originality being a segmentation of the probe along the quad axis. Together with an accurate magnet modelling, the measurement of the flux variations through the set of rotating coils allows to determine the magnetic field at each point. We use the 3D field formalism, i.e., the Fourier-Bessel expansion of the field obtained by solving the Laplace equation. We describe the QMM method and then the apparatus consisting in two probes of length 1.6 m and 3.2 m built to map the three quadrupoles Q1, Q2, Q3. Data processing uses Fourier analysis. The mapping of the Electron Arm took place in situ in 1996. A first set of results concerns integral measurements including the properties of excitation cycle of the magnets (saturation and hysteresis). Second set of results in terms of local field yields the 3D field maps of the quadrupoles. After having applied corrections to the data we obtain a local field accuracy of 5 Gauss on each component, i.e. an uncertainty of 5.10 -4 relative to the quadrupole central field. We use SNAKE ray-tracing code with the implementation of QMM field maps and obtain preliminary results on HRS optics. (author)

QQDDQ magnet spectrometer 'BIG KARL'

Energy Technology Data Exchange (ETDEWEB)

Martin, S A; Hardt, A; Meissburger, J; Berg, G P.A.; Hacker, U; Huerlimann, W; Roemer, J G.M.; Sagefka, T; Retz, A; Schult, O W.B.

1983-09-01

A magnet spectrometer consisting of two quadrupoles, two dipole magnets and another larger quadrupole in front of the detector was designed and installed at the nuclear research institute of the KFA Juelich. It has been used for charged-particle spectroscopy at the isochronous cyclotron since early 1979. Special features of the spectrometer are variable and high dispersion, coils for higher order field corrections in the dipole magnets and a focal plane perpendicular to the optical axis. A large mass-energy product of mE/q/sup 2/ < 540 u x MeV, an angular acceptance of d..cap omega..<12.5 msr, a high resolving power of p/..delta..p up to 3 x 10/sup 4/ and the possibility of kinematical corrections up to K=0.8 make the instrument a very versatile tool for many experiments in the fields of nuclear and atomic physics. 51 references.

Cyclotrons as mass spectrometers

International Nuclear Information System (INIS)

Clark, D.J.

1984-04-01

The principles and design choices for cyclotrons as mass spectrometers are described. They are illustrated by examples of cyclotrons developed by various groups for this purpose. The use of present high energy cyclotrons for mass spectrometry is also described. 28 references, 12 figures

Chemical characterization of microparticles by laser ablation in an ion trap mass spectrometer

International Nuclear Information System (INIS)

Dale, J.M.; Whitten, W.B.; Ramsey, J.M.

1991-01-01

We are developing a new technique for the chemical characterization of microparticles based upon the use of electrodynamic traps. The electrodynamic trap has achieved widespread use in the mass spectrometry community in the form of the ion trap mass spectrometer or quadrupole ion trap. Small macroscopic particles can be confined or leviated within the electrode structure of a three-dimensional quadrupole electrodynamic trap in the same way as fundamental charges or molecular ions by using a combination of ac and dc potentials. Our concept is to use the same electrode structure to perform both microparticle levitation and ion trapping/mass analysis. The microparticle will first be trapped and spatially stabilized within the trap for characterization by optical probes, i.e., absorption, fluorescence, or Raman spectroscopy. After the particle has been optically characterized, it is further characterized using mass spectrometry. Ions are generated from the particle surface using laser ablation or desorption. The characteristics of the applied voltages are changed to trap the ions formed by the laser with the ions subsequently mass analyzed. The work described in this paper focuses on the ability to perform laser desorption experiments on microparticles contained within the ion trap. Laser desorption has previously been demonstrated in ion trap devices by applying the sample to a probe which is inserted so as to place the sample at the surface of the ring electrode. Our technique requires the placement of a microparticle in the center of the trap. Our initial experiments have been performed on falling microparticles rather than levitated particles to eliminate voltage switching requirements when changing from particle to ion trapping modes

Dynamical interplay between pairing and quadrupole correlations in odd-mass nuclei

International Nuclear Information System (INIS)

Kaneko, Kazunari; Takada, Kenjiro; Sakata, Fumihiko; Tazaki, Shigeru.

1982-01-01

Study of the dynamical interplay between pairing and quadrupole correlations in odd-mass nuclei has been developed. One of the purposes of this paper is to predict that the new collective excited states may exist system-atically in odd-mass nuclei. Other purpose is to discuss a new collective band structure on the top of a unique-parity one-quasiparticle state. Through the numerical calculations, it has been clarified that the dynamical mutual interplay between the pairing and the quadrupole degrees of freedom played an important role in the odd-mass transitional nuclei to bring about the new type of collective states. The results of calculation were compared with the experimental data. (Kato, T.)

Series fabrication of the main quadrupole cold masses for the LHC begins

CERN Multimedia

2003-01-01

Three hundred and sixty main quadrupole (MQ) magnets will perform the principal beam focusing around the 27 km LHC ring. CERN and CEA-Saclay began collaborating on the development and prototyping of these magnets in 1989. This resulted in five highly successful quadrupole units - also known as short straight sections - one of which was integrated for testing in String 1, and two others of the final design in String 2. Once the tests had confirmed the validity of the design and realization, the fabrication of the 360 cold masses had to be transferred to industry.The German firm ACCEL Instruments was entrusted both with the construction of the quadrupole magnets themselves, and with their assembly into the cold masses together with various combinations of corrector magnets produced by other European manufacturers. Here we see the first of the cold masses containing the MQ magnet of the machine arcs together with two types of corrector magnet ready for shipping to CERN. Pictured with this first unit, delivered o...

Efficient mass calibration of magnetic sector mass spectrometers

International Nuclear Information System (INIS)

Roddick, J.C.

1996-01-01

Magnetic sector mass spectrometers used for automatic acquisition of precise isotopic data are usually controlled with Hall probes and software that uses polynomial equations to define and calibrate the mass-field relations required for mass focusing. This procedure requires a number of reference masses and careful tuning to define and maintain an accurate mass calibration. A simplified equation is presented and applied to several different magnetically controlled mass spectrometers. The equation accounts for nonlinearity in typical Hall probe controlled mass-field relations, reduces calibration to a linear fitting procedure, and is sufficiently accurate to permit calibration over a mass range of 2 to 200 amu with only two defining masses. Procedures developed can quickly correct for normal drift in calibrations and compensate for drift during isotopic analysis over a limited mass range such as a single element. The equation is: Field A·Mass 1/2 + B·(Mass) p where A, B, and p are constants. The power value p has a characteristic value for a Hall probe/controller and is insensitive to changing conditions, thus reducing calibration to a linear regression to determine optimum A and B. (author). 1 ref., 1 tab., 6 figs

Indigenously built resonance ionization mass spectrometer

International Nuclear Information System (INIS)

Razvi, M.A.N.; Jayasekharan, T.; Thankarajan, K.; Guhagarkar, M.B.; Dixit, M.N.; Bhale, G.L.

2000-04-01

Design, fabrication and performance testing of an indigenously built Resonance Ionization Mass Spectrometer (RIMS) is presented in this report. The instrument is totally indigenous, but for the laser components consisting of the excimer laser and tunable dye lasers. Constructional details of atomic beam source and linear time-of-flight mass spectrometer are included. Finally, commissioning and performance testing of the instrument is described. Mass resolving power of 400 and a detection limit of 100 atoms has been achieved using this RIMS set-up. (author)

The Neutral Mass Spectrometer on the Lunar Atmosphere and Dust Environment Explorer Mission

Science.gov (United States)

Mahaffy, Paul R.; Hodges, R. Richard; Benna, Mehdi; King, Todd; Arvey, Robert; Barciniak, Michael; Bendt, Mirl; Carigan, Daniel; Errigo, Therese; Harpold, Daniel N.;

Comprehensive two-dimensional gas chromatography in combination with rapid scanning quadrupole mass spectrometry in perfume analysis.

Science.gov (United States)

Mondello, Luigi; Casillia, Alessandro; Tranchida, Peter Quinto; Dugo, Giovanni; Dugo, Paola

2005-03-04

Single column gas chromatography (GC) in combination with a flame ionization detector (FID) and/or a mass spectrometer is routinely employed in the determination of perfume profiles. The latter are to be considered medium to highly complex matrices and, as such, can only be partially separated even on long capillaries. Inevitably, several monodimensional peaks are the result of two or more overlapping components, often hindering reliable identification and quantitation. The present investigation is based on the use of a comprehensive GC (GC x GC) method, in vacuum outlet conditions, for the near to complete resolution of a complex perfume sample. A rapid scanning quadrupole mass spectrometry (qMS) system, employed for the assignment of GC x GC peaks, supplied high quality mass spectra. The validity of the three-dimensional (3D) GC x GC-qMS application was measured and compared to that of GC-qMS analysis on the same matrix. Peak identification, in all applications, was achieved through MS spectra library matching and the interactive use of linear retention indices (LRI).

Efficient mass calibration of magnetic sector mass spectrometers

Energy Technology Data Exchange (ETDEWEB)

Roddick, J C

1997-12-31

Magnetic sector mass spectrometers used for automatic acquisition of precise isotopic data are usually controlled with Hall probes and software that uses polynomial equations to define and calibrate the mass-field relations required for mass focusing. This procedure requires a number of reference masses and careful tuning to define and maintain an accurate mass calibration. A simplified equation is presented and applied to several different magnetically controlled mass spectrometers. The equation accounts for nonlinearity in typical Hall probe controlled mass-field relations, reduces calibration to a linear fitting procedure, and is sufficiently accurate to permit calibration over a mass range of 2 to 200 amu with only two defining masses. Procedures developed can quickly correct for normal drift in calibrations and compensate for drift during isotopic analysis over a limited mass range such as a single element. The equation is: Field A{center_dot}Mass{sup 1/2} + B{center_dot}(Mass){sup p} where A, B, and p are constants. The power value p has a characteristic value for a Hall probe/controller and is insensitive to changing conditions, thus reducing calibration to a linear regression to determine optimum A and B. (author). 1 ref., 1 tab., 6 figs.

Series fabrication of the main quadrupole cold masses for the LHC begins

CERN Multimedia

2003-01-01

Three hundred and sixty main quadrupole (MQ) magnets will perform the principal beam focusing around the 27 km LHC ring. CERN and CEA-Saclay began collaborating on the development and prototyping of these magnets in 1989. This resulted in five highly successful quadrupole units - also known as short straight sections - one of which was integrated for testing in String 1, and two others of the final design in String 2. Once the tests had confirmed the validity of the design and realization, the fabrication of the 360 cold masses had to be transferred to industry.The German firm ACCEL Instruments was entrusted both with the construction of the quadrupole magnets themselves, and with their assembly into the cold masses together with various combinations of corrector magnets produced by other European manufacturers. Here we see the first of the cold masses containing the MQ magnet of the machine arcs together with two types of corrector magnet ready for shipping to CERN. This first unit was delivered on 12 Februa...

An Automated High Performance Capillary Liquid Chromatography Fourier Transform Ion Cyclotron Resonance Mass Spectrometer for High-Throughput Proteomics

International Nuclear Information System (INIS)

Belov, Mikhail E.; Anderson, Gordon A.; Wingerd, Mark A.; Udseth, Harold R.; Tang, Keqi; Prior, David C.; Swanson, Kenneth R.; Buschbach, Michael A.; Strittmatter, Eric F.; Moore, Ronald J.; Smith, Richard D.

2004-01-01

We report on a fully automated 9.4 tesla Fourier transform ion resonance cyclotron (FTICR) mass spectrometer coupled to reverse-phase chromatography for high-throughput proteomic studies. Modifications made to the front-end of a commercial FTICR instrument--a dual-ESI-emitter ion source; dual-channel electrodynamic ion funnel; and collisional-cooling, selection and accumulation quadrupoles--significantly improved the sensitivity, dynamic range and mass measurement accuracy of the mass spectrometer. A high-pressure capillary liquid chromatography (LC) system was incorporated with an autosampler that enabled 24 h/day operation. A novel method for accumulating ions in the ICR cell was also developed. Unattended operation of the instrument revealed the exceptional reproducibility (1-5% deviation in elution times for peptides from a bacterial proteome), repeatability (10-20% deviation in detected abundances for peptides from the same aliquot analyzed a few weeks apart) and robustness (high-throughput operation for 5 months without downtime) of the LC/FTICR system. When combined with modulated-ion-energy gated trapping, the internal calibration of FTICR mass spectra decreased dispersion of mass measurement errors for peptide identifications in conjunction with high resolution capillary LC separations to < 5 ppm over a dynamic range for each spectrum of 10 3

Digitally synthesized high purity, high-voltage radio frequency drive electronics for mass spectrometry

Science.gov (United States)

Schaefer, R. T.; MacAskill, J. A.; Mojarradi, M.; Chutjian, A.; Darrach, M. R.; Madzunkov, S. M.; Shortt, B. J.

2008-09-01

Reported herein is development of a quadrupole mass spectrometer controller (MSC) with integrated radio frequency (rf) power supply and mass spectrometer drive electronics. Advances have been made in terms of the physical size and power consumption of the MSC, while simultaneously making improvements in frequency stability, total harmonic distortion, and spectral purity. The rf power supply portion of the MSC is based on a series-resonant LC tank, where the capacitive load is the mass spectrometer itself, and the inductor is a solenoid or toroid, with various core materials. The MSC drive electronics is based on a field programmable gate array (FPGA), with serial peripheral interface for analog-to-digital and digital-to-analog converter support, and RS232/RS422 communications interfaces. The MSC offers spectral quality comparable to, or exceeding, that of conventional rf power supplies used in commercially available mass spectrometers; and as well an inherent flexibility, via the FPGA implementation, for a variety of tasks that includes proportional-integral derivative closed-loop feedback and control of rf, rf amplitude, and mass spectrometer sensitivity. Also provided are dc offsets and resonant dipole excitation for mass selective accumulation in applications involving quadrupole ion traps; rf phase locking and phase shifting for external loading of a quadrupole ion trap; and multichannel scaling of acquired mass spectra. The functionality of the MSC is task specific, and is easily modified by simply loading FPGA registers or reprogramming FPGA firmware.

Digitally synthesized high purity, high-voltage radio frequency drive electronics for mass spectrometry.

Science.gov (United States)

Schaefer, R T; MacAskill, J A; Mojarradi, M; Chutjian, A; Darrach, M R; Madzunkov, S M; Shortt, B J

2008-09-01

Reported herein is development of a quadrupole mass spectrometer controller (MSC) with integrated radio frequency (rf) power supply and mass spectrometer drive electronics. Advances have been made in terms of the physical size and power consumption of the MSC, while simultaneously making improvements in frequency stability, total harmonic distortion, and spectral purity. The rf power supply portion of the MSC is based on a series-resonant LC tank, where the capacitive load is the mass spectrometer itself, and the inductor is a solenoid or toroid, with various core materials. The MSC drive electronics is based on a field programmable gate array (FPGA), with serial peripheral interface for analog-to-digital and digital-to-analog converter support, and RS232/RS422 communications interfaces. The MSC offers spectral quality comparable to, or exceeding, that of conventional rf power supplies used in commercially available mass spectrometers; and as well an inherent flexibility, via the FPGA implementation, for a variety of tasks that includes proportional-integral derivative closed-loop feedback and control of rf, rf amplitude, and mass spectrometer sensitivity. Also provided are dc offsets and resonant dipole excitation for mass selective accumulation in applications involving quadrupole ion traps; rf phase locking and phase shifting for external loading of a quadrupole ion trap; and multichannel scaling of acquired mass spectra. The functionality of the MSC is task specific, and is easily modified by simply loading FPGA registers or reprogramming FPGA firmware.

High-performance multiple-reflection time-of-flight mass spectrometers for research with exotic nuclei and for analytical mass spectrometry

Science.gov (United States)

Plaß, Wolfgang R.; Dickel, Timo; Ayet San Andres, Samuel; Ebert, Jens; Greiner, Florian; Hornung, Christine; Jesch, Christian; Lang, Johannes; Lippert, Wayne; Majoros, Tamas; Short, Devin; Geissel, Hans; Haettner, Emma; Reiter, Moritz P.; Rink, Ann-Kathrin; Scheidenberger, Christoph; Yavor, Mikhail I.

2015-11-01

A class of multiple-reflection time-of-flight mass spectrometers (MR-TOF-MSs) has been developed for research with exotic nuclei at present and future accelerator facilities such as GSI and FAIR (Darmstadt), and TRIUMF (Vancouver). They can perform highly accurate mass measurements of exotic nuclei, serve as high-resolution, high-capacity mass separators and be employed as diagnostics devices to monitor the production, separation and manipulation of beams of exotic nuclei. In addition, a mobile high-resolution MR-TOF-MS has been developed for in situ applications in analytical mass spectrometry ranging from environmental research to medicine. Recently, the MR-TOF-MS for GSI and FAIR has been further developed. A novel RF quadrupole-based ion beam switchyard has been developed that allows merging and splitting of ion beams as well as transport of ions into different directions. It efficiently connects a test and reference ion source and an auxiliary detector to the system. Due to an increase in the kinetic energy of the ions in the time-of-flight analyzer of the MR-TOF-MS, a given mass resolving power is now achieved in less than half the time-of-flight. Conversely, depending on the time-of-flight, the mass resolving power has been increased by a factor of more than two.

Application of the mass-spectrometer MASHA for mass-spectrometry and laser-spectroscopy

Science.gov (United States)

Rodin, A. M.; Belozerov, A. V.; Dmitriev, S. N.; Oganessian, Yu. Ts.; Sagaidak, R. N.; Salamatin, V. S.; Stepantsov, S. V.; Vanin, D. V.

2010-02-01

We report the present status of the mass-spectrometer MASHA (Mass-Analyzer of Supper Heavy Atoms) designed for determination of the masses of superheavy elements. The mass-spectrometer is connected to the U-400M cyclotron of the Flerov Laboratory for Nuclear Reactions (FLNR) JINR, Dubna. The first experiments on mass-measurements for 112 and 114 elements will be performed in the upcoming 2010. For this purpose a hot catcher, based on a graphite stopper, is constructed. The α-decay of the superheavy nuclides or spontaneous fission products will be detected with a silicon 192 strips detector. The experimental program of future investigations using the technique of a gas catcher is discussed. It should be regarded as an alternative of the classical ISOL technique. The possibilities are considered for using this mass-spectrometer for laser spectroscopy of nuclei far off-stability.

Application of the mass-spectrometer MASHA for mass-spectrometry and laser-spectroscopy

International Nuclear Information System (INIS)

Rodin, A. M.; Belozerov, A. V.; Dmitriev, S. N.; Oganessian, Yu. Ts.; Sagaidak, R. N.; Salamatin, V. S.; Stepantsov, S. V.; Vanin, D. V.

2010-01-01

We report the present status of the mass-spectrometer MASHA (Mass-Analyzer of Supper Heavy Atoms) designed for determination of the masses of superheavy elements. The mass-spectrometer is connected to the U-400M cyclotron of the Flerov Laboratory for Nuclear Reactions (FLNR) JINR, Dubna. The first experiments on mass-measurements for 112 and 114 elements will be performed in the upcoming 2010. For this purpose a hot catcher, based on a graphite stopper, is constructed. The α-decay of the superheavy nuclides or spontaneous fission products will be detected with a silicon 192 strips detector. The experimental program of future investigations using the technique of a gas catcher is discussed. It should be regarded as an alternative of the classical ISOL technique. The possibilities are considered for using this mass-spectrometer for laser spectroscopy of nuclei far off-stability.

Application of the mass-spectrometer MASHA for mass-spectrometry and laser-spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Rodin, A. M., E-mail: rodin@nrmail.jinr.ru; Belozerov, A. V.; Dmitriev, S. N.; Oganessian, Yu. Ts.; Sagaidak, R. N.; Salamatin, V. S.; Stepantsov, S. V.; Vanin, D. V. [JINR, Flerov Laboratory of Nuclear Reactions (Russian Federation)

2010-02-15

We report the present status of the mass-spectrometer MASHA (Mass-Analyzer of Supper Heavy Atoms) designed for determination of the masses of superheavy elements. The mass-spectrometer is connected to the U-400M cyclotron of the Flerov Laboratory for Nuclear Reactions (FLNR) JINR, Dubna. The first experiments on mass-measurements for 112 and 114 elements will be performed in the upcoming 2010. For this purpose a hot catcher, based on a graphite stopper, is constructed. The {alpha}-decay of the superheavy nuclides or spontaneous fission products will be detected with a silicon 192 strips detector. The experimental program of future investigations using the technique of a gas catcher is discussed. It should be regarded as an alternative of the classical ISOL technique. The possibilities are considered for using this mass-spectrometer for laser spectroscopy of nuclei far off-stability.

LADEE Neutral Mass Spectrometer Data

Data.gov (United States)

National Aeronautics and Space Administration — This bundle contains the data collected by the Neutral Mass Spectrometer (NMS) instrument aboard the Lunar Atmosphere and Dust Environment Explorer (LADEE)...

A Shuttle Upper Atmosphere Mass Spectrometer /SUMS/ experiment

Science.gov (United States)

Blanchard, R. C.; Duckett, R. J.; Hinson, E. W.

1982-01-01

A magnetic mass spectrometer is currently being adapted to the Space Shuttle Orbiter to provide repeated high altitude atmosphere data to support in situ rarefied flow aerodynamics research, i.e., in the high velocity, low density flight regime. The experiment, called Shuttle Upper Atmosphere Mass Spectrometer (SUMS), is the first attempt to design mass spectrometer equipment for flight vehicle aerodynamic data extraction. The SUMS experiment will provide total freestream atmospheric quantitites, principally total mass density, above altitudes at which conventional pressure measurements are valid. Experiment concepts, the expected flight profile, tradeoffs in the design of the total system and flight data reduction plans are discussed. Development plans are based upon a SUMS first flight after the Orbiter initial development flights.

Triple Quadrupole Versus High Resolution Quadrupole-Time-of-Flight Mass Spectrometry for Quantitative LC-MS/MS Analysis of 25-Hydroxyvitamin D in Human Serum

Science.gov (United States)

Geib, Timon; Sleno, Lekha; Hall, Rabea A.; Stokes, Caroline S.; Volmer, Dietrich A.

2016-08-01

We describe a systematic comparison of high and low resolution LC-MS/MS assays for quantification of 25-hydroxyvitamin D3 in human serum. Identical sample preparation, chromatography separations, electrospray ionization sources, precursor ion selection, and ion activation were used; the two assays differed only in the implemented final mass analyzer stage; viz. high resolution quadrupole-quadrupole-time-of-flight (QqTOF) versus low resolution triple quadrupole instruments. The results were assessed against measured concentration levels from a routine clinical chemiluminescence immunoassay. Isobaric interferences prevented the simple use of TOF-MS spectra for extraction of accurate masses and necessitated the application of collision-induced dissociation on the QqTOF platform. The two mass spectrometry assays provided very similar analytical figures of merit, reflecting the lack of relevant isobaric interferences in the MS/MS domain, and were successfully applied to determine the levels of 25-hydroxyvitamin D for patients with chronic liver disease.

Polymer and Additive Mass Spectrometry Literature Review

Energy Technology Data Exchange (ETDEWEB)

Shear, Trevor Allan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-06-06

The use of mass spectrometry in fields related to polymers has increased significantly over the past three decades and will be explored in this literature review. The importance of this technique is highlighted when exploring how polymers degrade, verifying purchased materials, and as internal requirements change. The primary focus will be on four ionization techniques and the triple quadrupole and quadrupole / time-of-flight mass spectrometers. The advantages and limitations of each will also be explored.

Extending The Useful Life Of Older Mass Spectrometers

International Nuclear Information System (INIS)

Johnson, S.; Cordaro, J.; Holland, M.; Jones, V.

2010-01-01

Thermal ionization and gas mass spectrometers are widely used across the Department of Energy (DOE) Complex and contractor laboratories. These instruments support critical missions, where high reliability and low measurement uncertainty are essential. A growing number of these mass spectrometers are significantly older than their original design life. The reality is that manufacturers have declared many of the instrument models obsolete, with direct replacement parts and service no longer available. Some of these obsolete models do not have a next generation, commercially available replacement. Today's budget conscious economy demands for the use of creative funds management. Therefore, the ability to refurbish (or upgrade) these valuable analytical tools and extending their useful life is a cost effective option. The Savannah River Site (SRS) has the proven expertise to breathe new life into older mass spectrometers, at a significant cost savings compared to the purchase and installation of new instruments. A twenty-seven year old Finnigan MAT-261(trademark) Thermal Ionization Mass Spectrometer (TIMS), located at the SRS F/H Area Production Support Laboratory, has been successfully refurbished. Engineers from the Savannah River National Laboratory (SRNL) fabricated and installed the new electronics. These engineers also provide continued instrument maintenance services. With electronic component drawings being DOE Property, other DOE Complex laboratories have the option to extend the life of their aged Mass Spectrometers.

Multi-elemental analysis of aqueous geochemical samples by quadrupole inductively coupled plasma-mass spectrometry (ICP-MS)

Science.gov (United States)

Wolf, Ruth E.; Adams, Monique

2015-01-01

Typically, quadrupole inductively coupled plasma-mass spectrometry (ICP-MS) is used to determine as many as 57 major, minor, and trace elements in aqueous geochemical samples, including natural surface water and groundwater, acid mine drainage water, and extracts or leachates from geological samples. The sample solution is aspirated into the inductively coupled plasma (ICP) which is an electrodeless discharge of ionized argon gas at a temperature of approximately 6,000 degrees Celsius. The elements in the sample solution are subsequently volatilized, atomized, and ionized by the ICP. The ions generated are then focused and introduced into a quadrupole mass filter which only allows one mass to reach the detector at a given moment in time. As the settings of the mass analyzer change, subsequent masses are allowed to impact the detector. Although the typical quadrupole ICP-MS system is a sequential scanning instrument (determining each mass separately), the scan speed of modern instruments is on the order of several thousand masses per second. Consequently, typical total sample analysis times of 2–3 minutes are readily achievable for up to 57 elements.

Theoretical resolving power of a radiofrequency mass spectrometer

International Nuclear Information System (INIS)

Coc, A.; Le Gac, R.; Saint Simon, M. de; Thibault, C.; Touchard, F.

1988-01-01

Radiofrequency mass spectrometers of L.G. Smith's type can reach a resolving power of 10 6 -10 7 and a precision of 10 -9 -10 -10 . The resolving power, shape of peaks and limitations are described. As an example, the spectrometer to be used in an experiment aimed at measuring the anti p/p mass ratio is considered. (orig.)

Automation of a thermal ionisation mass spectrometer

International Nuclear Information System (INIS)

Pamula, A.; Leuca, M.; Albert, S.; Benta, Adriana

2001-01-01

A thermal ionization mass spectrometer was upgraded in order to be monitored by a PC. A PC-LMP-16 National Instruments data acquisition board was used for the ion current channel and the Hall signal channel. A dedicated interface was built to allow commands from the computer to the current supply of the analyzing magnet and to the high voltage unit of the mass spectrometer. A software application was worked out to perform the adjustment of the spectrometer, magnetic scanning and mass spectra acquisition, data processing and isotope ratio determination. The apparatus is used for isotope ratio 235 U/ 238 U determination near the natural abundance. A peak jumping technique is applied to choose between the 235 U and 238 U signal, by switching the high voltage applied to the ion source between two preset values. This avoids the delay between the acquisition of the peaks of interest, a delay that would appear in the case of a 'pure' magnetic scanning. Corrections are applied for the mass discrimination effects and a statistical treatment of the data is achieved. (authors)

Mass-spectrometer of knock-on nuclei for reactor 'Pik'

International Nuclear Information System (INIS)

Begzhanov, P.B.; Nazarov, A.G.; Petrov, G.A.; Pikul', V.P.

1999-01-01

For reactor 'Pik' (that is being built in St. Petersburg Institute of Nuclear Physics) there was designed a universal two shoulder mass-spectrometer for non-decelerated fission products (FP) of nuclei. The spectrometer helps to obtain different values of linear magnification, dispersion, aberration coefficients and transmission without making structural changes in the device. To separate FP for one shoulder of spectrometer we chose ion-optical scheme (IOS) consisting of three electrostatic analyzers and three-sectional magnet 'JOSEF' that had high dispersion by masses at small deflection radius. IOS calculations of mass-spectrometer were performed with the help of program TRANSVOL (transfer of phase volume) designed basing on TRIO program. The program allows calculating of complete IOS transmission with taking into account elements aperture and beam officering

Comparison of ion coupling strategies for a microengineered quadrupole mass filter.

Science.gov (United States)

Wright, Steven; Syms, Richard R A; O'Prey, Shane; Hong, Guodong; Holmes, Andrew S

2009-01-01

The limitations of conventional machining and assembly techniques require that designs for quadrupole mass analyzers with rod diameters less than a millimeter are not merely scale versions of larger instruments. We show how silicon planar processing techniques and microelectromechanical systems (MEMS) design concepts can be used to incorporate complex features into the construction of a miniature quadrupole mass filter chip that could not easily be achieved using other microengineering approaches. Three designs for the entrance and exit to the filter consistent with the chosen materials and techniques have been evaluated. The differences between these seemingly similar structures have a significant effect on the performance. Although one of the designs results in severe attenuation of transmission with increasing mass, the other two can be scanned to m/z = 400 without any corruption of the mass spectrum. At m/z = 219, the variation in the transmission of the three designs was found to be approximately four orders of magnitude. A maximum resolution of M/DeltaM = 87 at 10% peak height has been achieved at m/z = 219 with a filter operated at 6 MHz and constructed using rods measuring (508 +/- 5) microm in diameter.

Mass-spectrometer MASHA - testing results on heavy ion beam

International Nuclear Information System (INIS)

Rodin, A.M.; Belozerov, A.V.; Vanin, D.V.; Dmitriev, S.N.; Itkis, M.G.; Kliman, J.; Krupa, L.; Lebedev, A.N.; Oganesyan, Yu.Ts.; Salamatin, V.S.; Sivachek, I.; Chernysheva, E.V.; Yukhimchuk, S.A.

2011-01-01

Description of mass-spectrometer MASHA, developed for the mass identification of superheavy elements, is given. The efficiency and operation speed in the off-line mode were measured with four calibrated leakages of noble gases. The total efficiency and operation speed of mass-spectrometer with hot catcher and ECR ion source were determined using the 40 Ar beam. The test experiment was carried out by measuring the alpha decay of Hg and Rn isotopes, produced in fusion reactions 40 Ar+ nat Sm→ nat-xn Hg+xn and 40 Ar+ 166 Er→ 206-xn Rn+xn, in the focal plane of mass-spectrometer. The operation speed of the given technique and relative yields of isotopes in the test reactions were determined

Inficon Transpector MPH Mass Spectrometer Random Vibration Test Report

Science.gov (United States)

Santiago-Bond, Jo; Captain, Janine

2015-01-01

The purpose of this test report is to summarize results from the vibration testing of the INFICON Transpector MPH100M model Mass Spectrometer. It also identifies requirements satisfied, and procedures used in the test. As a payload of Resource Prospector, it is necessary to determine the survivability of the mass spectrometer to proto-qualification level random vibration. Changes in sensitivity of the mass spectrometer can be interpreted as a change in alignment of the instrument. The results of this test will be used to determine any necessary design changes as the team moves forward with flight design.

Precise mass measurements of exotic nuclei--the SHIPTRAP Penning trap mass spectrometer

International Nuclear Information System (INIS)

Herfurth, F.; Ackermann, D.; Block, M.; Dworschak, M.; Eliseev, S.; Hessberger, F.; Hofmann, S.; Kluge, H.-J.; Maero, G.; Martin, A.; Mazzocco, M.; Rauth, C.; Vorobjev, G.; Blaum, K.; Ferrer, R.; Neidherr, D.; Chaudhuri, A.; Marx, G.; Schweikhard, L.; Neumayr, J.

2007-01-01

The SHIPTRAP Penning trap mass spectrometer has been designed and constructed to measure the mass of short-lived, radioactive nuclei. The radioactive nuclei are produced in fusion-evaporation reactions and separated in flight with the velocity filter SHIP at GSI in Darmstadt. They are captured in a gas cell and transfered to a double Penning trap mass spectrometer. There, the cyclotron frequencies of the radioactive ions are determined and yield mass values with uncertainties ≥4.5·10 -8 . More than 50 nuclei have been investigated so far with the present overall efficiency of about 0.5 to 2%

Advanced mass spectrometers for hydrogen-isotope analyses

International Nuclear Information System (INIS)

Chastagner, P.; Daves, H.L.; Hess, W.B.

1982-01-01

Two advanced mass spectrometers for the accurate analysis of mixtures of the hydrogen isotopes were evaluated by Du Pont personnel at the Savannah River Laboratory. One is a large double-focusing instrument with a resolution of 2000 at mass 4 and an abundance sensitivity of >100,000 for the HT-D 2 doublet. The second is a smaller, simpler, stigmatic focusing instrument with exceptionally high ion intensities (>1 x 10 - 9 A at 600 resolution and about 1 x 10 - 10 A at 1300 resolution) for high signal-to-noise ratios. Both instruments are computer controlled. Once a scan is started, peak switching, scanning, mass discrimination control, data collection, and data reduction are done without operator intervention. Utility routines control hysteresis effects and instrument calibration. A containment facility, with dual inlet systems and a standard distribution system, permits testing with tritium mixtures. Helium flow standards and tritium activity meters provide independent verification of the mass spectrometer calibrations. A recovery system prevents the release of tritium to the environment. The performance of the mass spectrometers was essentially equal under simulated process control conditions. Precision and accuracy for the D/T ratio was <0.5% (rel 2sigma limits). Performance factors were: sample equilibration <300 ppM; linearity within +-0.3%; and gas interference <0.1%. Mass discrimination was controlled reliably by the computers

A radio frequency quadrupole ion beam buncher for ISOLTRAP

CERN Document Server

Bollen, G; Dezfuli, A M G; Henry, S; Herfurth, F; Kellerbauer, A G; Kim, T; Kluge, H J; Kohl, A; Lamour, E; Lunney, M D; Moore, R B; Quint, W; Schwarz, S; Varfalvy, P; Vermeeren, L

1998-01-01

ISOLTRAP is a Penning trap spectrometer at the on-line mass separator ISOLDE at CERN for the mass determination of radioisotopes. It consists of three electromagnetic traps in tandem; a Paul trap for ISOLDE beam collection, a Penning trap for cooling and purification and a high-precision Penning trap for the measurement of masses by cyclotron resonance. The Paul trap, which collects radionuclide ions using only electric fields and a noble buffer gas, has been essential for the masses of radionuclides that cannot be surface ionized. The success with this system has led to the present program to increase the collection efficiency by replacing the Paul trap by a radiofrequency quadrupole ion guide operating as a buncher. This system would also provide a DC ISOLDE beam of emittance approaching 1$\\pi$ -mm-mrad. (3 refs).

High-Resolution Mass Spectrometers

Science.gov (United States)

Marshall, Alan G.; Hendrickson, Christopher L.

2008-07-01

Over the past decade, mass spectrometry has been revolutionized by access to instruments of increasingly high mass-resolving power. For small molecules up to ˜400 Da (e.g., drugs, metabolites, and various natural organic mixtures ranging from foods to petroleum), it is possible to determine elemental compositions (CcHhNnOoSsPp…) of thousands of chemical components simultaneously from accurate mass measurements (the same can be done up to 1000 Da if additional information is included). At higher mass, it becomes possible to identify proteins (including posttranslational modifications) from proteolytic peptides, as well as lipids, glycoconjugates, and other biological components. At even higher mass (˜100,000 Da or higher), it is possible to characterize posttranslational modifications of intact proteins and to map the binding surfaces of large biomolecule complexes. Here we review the principles and techniques of the highest-resolution analytical mass spectrometers (time-of-flight and Fourier transform ion cyclotron resonance and orbitrap mass analyzers) and describe some representative high-resolution applications.

High-efficiency thermal ionization sources for mass spectrometry

International Nuclear Information System (INIS)

Olivares, Jose A.

1996-01-01

A version of the thermal ionization cavity (TIC) source developed specifically for use in mass spectrometry is presented. The performance of this ion source has been characterized extensively both with the use of an isotope separator and a quadrupole mass spectrometer. A detailed description of the TIC source for mass spectrometry is given along with the performance characteristics observed

The role of vacuum in the quality of TOF mass spectrometer

International Nuclear Information System (INIS)

Bhowmick, A.; Gadkari, S.C.; Yakhmi, J.V.; Sahni, V.C.

2005-01-01

The art in the designing of time-of-flight mass spectrometers has come across a long course of development. The present day state-of-the-art machines are essentially the outcome of knowledge from the advances in different other areas of technology. This article discusses exclusively the role of UHV to enhance the quality of the TOF mass spectrometers and its application to the recently developed high resolution TOF mass spectrometer at TP and PED-BARC. (author)

Direct mass measurements of neutron-deficient xenon isotopes using the ISOLTRAP mass spectrometer

CERN Document Server

Dilling, J; Beck, D; Bollen, G; Herfurth, F; Kellerbauer, A G; Kluge, H J; Moore, R B; Scheidenberger, C; Schwarz, S; Sikler, G

2004-01-01

The masses of the noble-gas Xe isotopes with 114 $\\leq$ A $\\leq$ 123 have been directly measured for the first time. The experiments were carried out with the ISOLTRAP triple trap spectrometer at the online mass separator ISOLDE/CERN. A mass resolving power of the Penning trap spectrometer of $m/\\Delta m$ of close to a million was chosen resulting in an accuracy of $\\delta m \\leq 13$ keV for all investigated isotopes. Conflicts with existing, indirectly obtained, mass data by several standard deviations were found and are discussed. An atomic mass evaluation has been performed and the results are compared to information from laser spectroscopy experiments and to recent calculations employing an interacting boson model.

A liquid chromatography method with single quadrupole mass spectrometry for quantitative determination of indomethacin in maternal plasma and urine of pregnant patients

Science.gov (United States)

Wang, Xiaoming; Vernikovskaya, Daria I.; Nanovskaya, Tatiana N.; Rytting, Erik; Hankins, Gary D.V.; Ahmed, Mahmoud S.

2013-01-01

A liquid chromatography with single quadrupole mass spectrometry method was developed for the quantitative determination of indomethacin in the maternal plasma and urine of pregnant patients under treatment. A deuterium-labeled isotope of indomethacin (d4-indomethacin) was used as an internal standard. The maternal plasma and urine samples were acidified with 1.0 MHCl then extracted with chloroform to achieve the extraction recovery range of 94% to 104% with variation less than 11%. Chromatographic separation was achieved by a Waters Symmetry C18 column with isocratic elution of 0.05% (v/v) formic acid aqueous solution and acetonitrile (47:53, v/v). An in-source fragmentation was applied on the single quadrupole mass spectrometer equipped with an electrospray ionization source at positive mode. The LC-ESI-MS quantification was performed in the selected ion monitoring mode targeting ions at m/z 139 for indomethacin and m/z 143 for its internal standard. The calibration curves were linear in the concentration ranges between 14.8 and 2.97×103 ng/mL for plasma samples and between 10.5 and 4.21×103 ng/mL for urine samples. The relative standard deviation of this method was less than 8% for intra- and inter-day assays, and the accuracy ranged between 90% and 108%. PMID:23474812

MOMA and other next-generation ion trap mass spectrometers for planetary exploration

Science.gov (United States)

Arevalo, R. D., Jr.; Brinckerhoff, W. B.; Getty, S.; Mahaffy, P. R.; van Amerom, F. H. W.; Danell, R.; Pinnick, V. T.; Li, X.; Grubisic, A.; Southard, A. E.; Hovmand, L.; Cottin, H.; Makarov, A.

2016-12-01

Since the 1970's, quadrupole mass spectrometer (QMS) systems have served as low-risk, cost-efficient means to explore the inner and outer reaches of the solar system. These legacy instruments have interrogated the compositions of the lunar exosphere (LADEE), surface materials on Mars (MSL), and the atmospheres of Venus (Pioneer Venus), Mars (MAVEN) and outer planets (Galileo and Cassini-Huygens). However, the in situ detection of organic compounds on Mars and Titan, coupled with ground-based measurements of amino acids in meteorites and a variety of organics in comets, has underlined the importance of molecular disambiguation in the characterization of high-priority planetary environments. The Mars Organic Molecule Analyzer (MOMA) flight instrument, centered on a linear ion trap, enables the in situ detection of volatile and non-volatile organics, but also the characterization of molecular structures through SWIFT ion isolation/excitation and tandem mass spectrometry (MSn). Like the SAM instrument on MSL, the MOMA investigation also includes a gas chromatograph (GC), thereby enabling the chemical separation of potential isobaric interferences based on retention times. The Linear Ion Trap Mass Spectrometer (LITMS; PI: William Brinckerhoff), developed to TRL 6 via the ROSES MatISSE Program, augments the core MOMA design and adds: expanded mass range (from 20 - 2000 Da); high-temperature evolved gas analysis (up to 1300°C); and, dual polarity detector assemblies (supporting the measurement of negative ions). The LITMS instrument will be tested in the field in 2017 through the Atacama Rover Astrobiology Drilling Studies (ARADS; PI: Brian Glass) ROSES PSTAR award. Following on these advancements, the Advanced Resolution Organic Molecule Analyzer (AROMA; PI: Ricardo Arevalo Jr.), supported through the ROSES PICASSO Program, combines a highly capable MOMA/LITMS-like linear ion trap and the ultrahigh resolution CosmOrbitrap mass analyzer developed by a consortium of five

Quantitation of isobaric phosphatidylcholine species in human plasma using a hybrid quadrupole linear ion-trap mass spectrometer

Czech Academy of Sciences Publication Activity Database

Žáček, Petr; Bukowski, M.; Rosenberger, T. A.; Picklo, M.

2016-01-01

Roč. 57, č. 12 (2016), s. 2225-2234 ISSN 0022-2275 Institutional support: RVO:61388963 Keywords : shotgun lipidomics * triple quadrupole/ion-trap * human blood plasma * phosphatidylcholines Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 4.810, year: 2016 http://www.jlr.org/content/57/12/2225.full

Determination of low concentrations of iron, arsenic, selenium, cadmium, and other trace elements in natural samples using an octopole collision/reaction cell equipped quadrupole-inductively coupled plasma mass spectrometer.

Science.gov (United States)

Dial, Angela R; Misra, Sambuddha; Landing, William M

2015-04-30

Accurate determination of trace metals has many applications in environmental and life sciences, such as constraining the cycling of essential micronutrients in biological production and employing trace metals as tracers for anthropogenic pollution. Analysis of elements such as Fe, As, Se, and Cd is challenged by the formation of polyatomic mass spectrometric interferences, which are overcome in this study. We utilized an Octopole Collision/Reaction Cell (CRC)-equipped Quadrupole-Inductively Coupled Plasma Mass Spectrometer for the rapid analysis of small volume samples (~250 μL) in a variety of matrices containing HNO3 and/or HCl. Efficient elimination of polyatomic interferences was demonstrated by the use of the CRC in Reaction Mode (RM; H2 gas) and in Collision-Reaction Mode (CRM; H2 and He gas), in addition to hot plasma (RF power 1500 W) and cool plasma (600 W) conditions. It was found that cool plasma conditions with RM achieved the greatest signal sensitivity while maintaining low detection limits (i.e. (56) Fe in 0.44 M HNO3 has a sensitivity of 160,000 counts per second (cps)-per-1 µg L(-1) and a limit of detection (LoD) of 0.86 ng L(-1) ). The average external precision was ≤ ~10% for minor (≤10 µg L(-1) ) elements measured in a 1:100 dilution of NIST 1643e and for iron in rainwater samples under all instrumental operating conditions. An improved method has been demonstrated for the rapid multi-element analysis of trace metals that are challenged by polyatomic mass spectrometric interferences, with a focus on (56) Fe, (75) As, (78) Se and (111) Cd. This method can contribute to aqueous environmental geochemistry and chemical oceanography, as well as other fields such as forensic chemistry, agriculture, food chemistry, and pharmaceutical sciences. Copyright © 2015 John Wiley & Sons, Ltd.

Generalized Kerr spacetime with an arbitrary mass quadrupole moment: geometric properties versus particle motion

International Nuclear Information System (INIS)

Bini, Donato; Geralico, Andrea; Luongo, Orlando; Quevedo, Hernando

2009-01-01

An exact solution of Einstein's field equations in empty space first found in 1985 by Quevedo and Mashhoon is analyzed in detail. This solution generalizes Kerr spacetime to include the case of matter with an arbitrary mass quadrupole moment and is specified by three parameters, the mass M, the angular momentum per unit mass a and the quadrupole parameter q. It reduces to the Kerr spacetime in the limiting case q = 0 and to the Erez-Rosen spacetime when the specific angular momentum a vanishes. The geometrical properties of such a solution are investigated. Causality violations, directional singularities and repulsive effects occur in the region close to the source. Geodesic motion and accelerated motion are studied on the equatorial plane which, due to the reflection symmetry property of the solution, also turns out to be a geodesic plane.

Determination of triacylglycerol regioisomers using electrospray ionization-quadrupole ion trap mass spectrometry with a kinetic method.

Science.gov (United States)

Leveque, Nathalie L; Acheampong, Akwasi; Heron, Sylvie; Tchapla, Alain

2012-04-13

The kinetic method was applied to differentiate and quantify mixtures of regioisomeric triacylglycerols (TAGs) by generating and mass selecting alkali ion bound metal dimeric clusters with a TAG chosen as reference (ref) and examining their competitive dissociations in a quadrupole ion trap mass spectrometer. This methodology readily distinguished pairs of regioisomers (AAB/ABA) such as LLO/LOL, OOP/OPO and SSP/SPS and consequently distinguished sn-1/sn-3, sn-2 substituents on the glycerol backbone. The dimeric complex ions [ref, Li, TAG((AAB and/or ABA))](+) generated by electrospray ionization mass spectrometry were subjected to collision induced dissociation causing competitive loss of either the neutral TAG reference (ref) leading to [Li(AAB and/or ABA)](+) or the neutral TAG molecule (TAG((AAB and/or ABA))) leading to [ref, Li](+). The ratio of the two competitive dissociation rates, defined by the product ion branching ratio (R(iso)), was related via the kinetic method to the regioisomeric composition of the investigated TAG mixture. In this work, a linear correlation was established between composition of the mixture of each TAG regioisomer and the logarithm of the branching ratio for competitive fragmentation. Depending on the availability of at least one TAG regioisomer as standard, the kinetic method and the standard additions method led to the quantitative analysis of natural TAG mixtures. Copyright © 2012 Elsevier B.V. All rights reserved.

Mass Spectrometry Instrumentation in Proteomics

DEFF Research Database (Denmark)

Sprenger, Richard Remko; Roepstorff, Peter

2012-01-01

Mass spectrometry has evolved into a crucial technology for the field of proteomics, enabling the comprehensive study of proteins in biological systems. Innovative developments have yielded flexible and versatile mass spectrometric tools, including quadrupole time-of-flight, linear ion trap......, Orbitrap and ion mobility instruments. Together they offer various and complementary capabilities in terms of ionization, sensitivity, speed, resolution, mass accuracy, dynamic range and methods of fragmentation. Mass spectrometers can acquire qualitative and quantitative information on a large scale...

Fabrication and testing of the recoil mass spectrometer at Bombay ...

Indian Academy of Sciences (India)

A recoil mass spectrometer (RMS) has been designed, fabricated and installed ... first order and only mass dispersion is obtained at the focal plane of the ... more details, like, the specifications and a typical beam profile through the ... Further experiments are now in progress to characterize the spectrometer, i.e., to measure.

Proton Transfer Time-of-Flight Mass Spectrometer

Energy Technology Data Exchange (ETDEWEB)

Watson, Thomas B. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2016-03-01

The Proton Transfer Reaction Mass Spectrometer (PTRMS) measures gas-phase compounds in ambient air and headspace samples before using chemical ionization to produce positively charged molecules, which are detected with a time-of-flight (TOF) mass spectrometer. This ionization method uses a gentle proton transfer reaction method between the molecule of interest and protonated water, or hydronium ion (H₃O⁺), to produce limited fragmentation of the parent molecule. The ions produced are primarily positively charged with the mass of the parent ion, plus an additional proton. Ion concentration is determined by adding the number of ions counted at the molecular ion’s mass-to-charge ratio to the number of air molecules in the reaction chamber, which can be identified according to the pressure levels in the reaction chamber. The PTRMS allows many volatile organic compounds in ambient air to be detected at levels from 10–100 parts per trillion by volume (pptv). The response time is 1 to 10 seconds.

A compact time-of-flight mass spectrometer for ion source characterization

International Nuclear Information System (INIS)

Chen, L.; Wan, X.; Jin, D. Z.; Tan, X. H.; Huang, Z. X.; Tan, G. B.

2015-01-01

A compact time-of-flight mass spectrometer with overall dimension of about 413 × 250 × 414 mm based on orthogonal injection and angle reflection has been developed for ion source characterization. Configuration and principle of the time-of-flight mass spectrometer are introduced in this paper. The mass resolution is optimized to be about 1690 (FWHM), and the ion energy detection range is tested to be between about 3 and 163 eV with the help of electron impact ion source. High mass resolution and compact configuration make this spectrometer useful to provide a valuable diagnostic for ion spectra fundamental research and study the mass to charge composition of plasma with wide range of parameters

Design of a new focused multipassage mass spectrometer

Energy Technology Data Exchange (ETDEWEB)

Boulanger, P [National Research Council of Canada, Ottawa, ON (Canada). Photonic and Sensors Section; Baril, M [Laval Univ., Quebec City (Canada). Dept. de Physique

1990-12-01

This paper descirbes a new type of multipassage mass spectrometer using tricylindrical mirrors as reflexive elements and a symmetric quadrupolar lens triplet as focusing element. We study the first order optics and then emphasize on beam transport problems as well as on conditions for maximum mass resolution. The effect of first and second order aberrations on the ultimate resolution of the spectrometer and the procedure for minimizing them by selecting proper operating conditions are discussed. The contributions of the third order aberration terms and of space charge are not considered. (orig.).

UV Photodissociation Action Spectroscopy of Haloanilinium Ions in a Linear Quadrupole Ion Trap Mass Spectrometer

Science.gov (United States)

Hansen, Christopher S.; Kirk, Benjamin B.; Blanksby, Stephen J.; O'Hair, Richard. A. J.; Trevitt, Adam J.

2013-06-01

UV-vis photodissociation action spectroscopy is becoming increasingly prevalent because of advances in, and commercial availability of, ion trapping technologies and tunable laser sources. This study outlines in detail an instrumental arrangement, combining a commercial ion-trap mass spectrometer and tunable nanosecond pulsed laser source, for performing fully automated photodissociation action spectroscopy on gas-phase ions. The components of the instrumentation are outlined, including the optical and electronic interfacing, in addition to the control software for automating the experiment and performing online analysis of the spectra. To demonstrate the utility of this ensemble, the photodissociation action spectra of 4-chloroanilinium, 4-bromoanilinium, and 4-iodoanilinium cations are presented and discussed. Multiple photoproducts are detected in each case and the photoproduct yields are followed as a function of laser wavelength. It is shown that the wavelength-dependent partitioning of the halide loss, H loss, and NH3 loss channels can be broadly rationalized in terms of the relative carbon-halide bond dissociation energies and processes of energy redistribution. The photodissociation action spectrum of (phenyl)Ag2 + is compared with a literature spectrum as a further benchmark.

A compact E × B filter: A multi-collector cycloidal focusing mass spectrometer

Energy Technology Data Exchange (ETDEWEB)

Blase, Ryan C., E-mail: rblase@swri.edu; Miller, Greg; Brockwell, Tim; Waite, J. Hunter [Southwest Research Institute, 6220 Culebra Road, San Antonio, Texas 78238 (United States); Westlake, Joseph [The Johns Hopkins University Applied Physics Laboratory LLC, 11100 Johns Hopkins Road, Laurel, Maryland 20723 (United States); Ostrom, Nathaniel; Ostrom, Peggy H. [Department of Integrative Biology, Michigan State University, 288 Farm Lane RM 203, East Lansing, Michigan 48824 (United States)

2015-10-15

A compact E × B mass spectrometer is presented. The mass spectrometer presented is termed a “perfect focus” mass spectrometer as the resolution of the device is independent of both the initial direction and energy of the ions (spatial and energy independent). The mass spectrometer is small in size (∼10.7 in.{sup 3}) and weight (∼2 kg), making it an attractive candidate for portability when using small, permanent magnets. A multi-collector Faraday cup design allows for the detection of multiple ion beams in discrete collectors simultaneously; providing the opportunity for isotope ratio monitoring. The mass resolution of the device is around 400 through narrow collector slits and the sensitivity of the device follows expected theoretical calculations of the ion current produced in the electron impact ion source. Example mass spectra obtained from the cycloidal focusing mass spectrometer are presented as well as information on mass discrimination based on instrumental parameters and isotope ratio monitoring of certain ion signals in separate Faraday cups.

Targeted analysis with benchtop quadrupole–orbitrap hybrid mass spectrometer: Application to determination of synthetic hormones in animal urine

International Nuclear Information System (INIS)

Kumar, Praveen; Rúbies, Antoni; Centrich, Francesc; Granados, Mercè; Cortés-Francisco, Nuria; Caixach, Josep; Companyó, Ramon

2013-01-01

Graphical abstract: -- Highlights: •The quadrupole in Q Exactive acts as a powerful filter to reduce ion suppression. •Reducing mass range using quadrupole in targeted modes increases the S/N ratio. •Targeted SIM data dependent scan modes are the most suitable for residue analysis. •A HRMS confirmatory method for synthetic hormones in urine has been developed. •The Q Exactive provides similar sensitivity and enhanced selectivity compared to QqQ. -- Abstract: Sensitive and unequivocal determination of analytes/contaminants in complex matrices is a challenge in the field of food safety control. In this study, various acquisition modes (Full MS/AIF, Full MS + tMS/MS, Full MS/dd MS/MS and tSIM/ddMS/MS) and parameters of a quadrupole–orbitrap hybrid mass spectrometer (Q Exactive) were studied in detail. One of the main conclusions has been that, reducing the scan range for Full MS (using the quadrupole) and targeted modes give higher signal-to-noise (S/N) ratios and thereby better detection limits for analytes in matrix. The use of Q Exactive in a complex case, for the confirmatory analysis of hormones in animal urine is presented. A targeted SIM data dependent MS/MS (tSIM/ddMS/MS) acquisition method for determination of eight synthetic hormones (trenbolone, 17α ethinylestradiol, zeranol, stanozolol, dienestrol, diethylstilbestrol, hexestrol, taleranol) and a naturally occurring hormone (zearalenone) in animal urine were optimized to have sensitive precursors from targeted SIM mode and trigger MS/MS scans over the entire chromatograph peak. The method was validated according to EC/657/2002. CCα (decision limit) for the analytes ranged between 0.11 μg L −1 and 0.69 μg L −1 and CCβ (detection capability) ranged between 0.29 μg L −1 and 0.90 μg L −1

Targeted analysis with benchtop quadrupole–orbitrap hybrid mass spectrometer: Application to determination of synthetic hormones in animal urine

Energy Technology Data Exchange (ETDEWEB)

Kumar, Praveen [Departament de Química Analítica, Universitat de Barcelona, Barcelona (Spain); Rúbies, Antoni; Centrich, Francesc [Laboratori Agència Salut Pública de Barcelona, Barcelona (Spain); CIBER of Epidemiology and Public Health (CIBERESP), Madrid (Spain); Granados, Mercè [Departament de Química Analítica, Universitat de Barcelona, Barcelona (Spain); Cortés-Francisco, Nuria; Caixach, Josep [Mass Spectrometry Laboratory-Organic Pollutants, IDAEA-CSIC, Barcelona (Spain); Companyó, Ramon, E-mail: compano@ub.edu [Departament de Química Analítica, Universitat de Barcelona, Barcelona (Spain)

2013-05-30

Graphical abstract: -- Highlights: •The quadrupole in Q Exactive acts as a powerful filter to reduce ion suppression. •Reducing mass range using quadrupole in targeted modes increases the S/N ratio. •Targeted SIM data dependent scan modes are the most suitable for residue analysis. •A HRMS confirmatory method for synthetic hormones in urine has been developed. •The Q Exactive provides similar sensitivity and enhanced selectivity compared to QqQ. -- Abstract: Sensitive and unequivocal determination of analytes/contaminants in complex matrices is a challenge in the field of food safety control. In this study, various acquisition modes (Full MS/AIF, Full MS + tMS/MS, Full MS/dd MS/MS and tSIM/ddMS/MS) and parameters of a quadrupole–orbitrap hybrid mass spectrometer (Q Exactive) were studied in detail. One of the main conclusions has been that, reducing the scan range for Full MS (using the quadrupole) and targeted modes give higher signal-to-noise (S/N) ratios and thereby better detection limits for analytes in matrix. The use of Q Exactive in a complex case, for the confirmatory analysis of hormones in animal urine is presented. A targeted SIM data dependent MS/MS (tSIM/ddMS/MS) acquisition method for determination of eight synthetic hormones (trenbolone, 17α ethinylestradiol, zeranol, stanozolol, dienestrol, diethylstilbestrol, hexestrol, taleranol) and a naturally occurring hormone (zearalenone) in animal urine were optimized to have sensitive precursors from targeted SIM mode and trigger MS/MS scans over the entire chromatograph peak. The method was validated according to EC/657/2002. CCα (decision limit) for the analytes ranged between 0.11 μg L{sup −1} and 0.69 μg L{sup −1} and CCβ (detection capability) ranged between 0.29 μg L{sup −1} and 0.90 μg L{sup −1}.

Electron attachment mass spectrometry as a diagnostics for electronegative gases and plasmas

NARCIS (Netherlands)

Stoffels - Adamowicz, E.; Stoffels, W.W.; Tachibana, K.

1998-01-01

Electron attachment mass spectrometry (EAMS) has been developed to study mixtures of electronegative gases and plasmas. A quadrupole mass spectrometer (QMS) has been used to detect negative ions, formed from sampled species by attachment of low energy electrons. Varying the electron energy allows to

Standard test method for analysis of isotopic composition of uranium in nuclear-grade fuel material by quadrupole inductively coupled plasma-mass spectrometry

CERN Document Server

American Society for Testing and Materials. Philadelphia

2000-01-01

1.1 This test method is applicable to the determination of the isotopic composition of uranium (U) in nuclear-grade fuel material. The following isotopic weight percentages are determined using a quadrupole inductively coupled plasma-mass spectrometer (Q-ICP-MS): 233U, 234U, 235U, 236U, and 238U. The analysis can be performed on various material matrices after acid dissolution and sample dilution into water or dilute nitric (HNO3) acid. These materials include: fuel product, uranium oxide, uranium oxide alloys, uranyl nitrate (UNH) crystals, and solutions. The sample preparation discussed in this test method focuses on fuel product material but may be used for uranium oxide or a uranium oxide alloy. Other preparation techniques may be used and some references are given. Purification of the uranium by anion-exchange extraction is not required for this test method, as it is required by other test methods such as radiochemistry and thermal ionization mass spectroscopy (TIMS). This test method is also described i...

New mass spectrometers for hydrogen isotope analyses

International Nuclear Information System (INIS)

Chastagner, P.; Daves, H.L.; Hess, W.B.

1981-01-01

Two advanced mass spectrometers for the accurate analysis of mixtures of the hydrogen isotopes are being evaluated by Du Pont personnel at the Savannah River Laboratory. One is a large double-focusing instrument with a resolution of 2000 at mass 4, an abundance sensitivity of > 100,000 for the HT-D 2 doublet, and a sophisticated electronic control and data collection system. The second is a smaller, simpler, stigmatic-focusing instrument in which exceptionally high ion intensities (> 1 x 10 -9 A) result in high signal to noise ratios. A containment facility with sample inlet systems and a standard distribution system was built to permit testing with tritium mixtures. The characteristics of the mass spectrometers under a variety of operating conditions will be presented. Factors to be discussed include: sample equilibration and its elimination; linearity; trimer formation; gas interference; stability; signal to noise ratio; mass discrimination; and anticipated precision and accu sublimed molybdenum collector of Converter No. 262; and (3) demonstration of tungsten CVD onto molybdenum flange using a reuseable graphite mandrel

Calcium Atom Trap for Atom Trap Mass Spectrometer

Energy Technology Data Exchange (ETDEWEB)

Ko, Kwang Hoon; Park, Hyun Min; Han, Jae Min; Kim, Taek Soo; Cha, Yong Ho; Lim, Gwon; Jeong, Do Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2012-05-15

Trace isotope analysis has been an important role in science, archaeological dating, geology, biology and nuclear industry. Artificially produced fission products such as Sr-90, Cs-135 and Kr-85 can be released to the environment when nuclear accident occurs and the reprocessing factory operates. Thus, the analysis of them has been of interest in nuclear industry. But it is difficult to detect them due to low natural abundance less then 10-10. The ultra-trace radio isotopes have been analyzed by the radio-chemical method, accelerator mass spectrometer, and laser based method. The radiochemical method has been used in the nuclear industry. But this method has disadvantages of long measurement time for long lived radioisotopes and toxic chemical process for the purification. The accelerator mass spectrometer has high isotope selectivity, but the system is huge and it has the isobar effects. The laser based method, such as RIMS (Resonance Ionization Mass Spectrometry) is a basically isobar-effect free method. Recently, ATTA (Atom Trap Trace Analysis), one of the laser based method, has been successfully demonstrated sufficient isotope selectivity with small system size. It has been applied for the detection of Kr-81 and Kr-85. However, it is not suitable for real sample detection, because it requires steady atomic beam generation during detection and is not allowed simultaneous detection of other isotopes. Therefore, we proposed the coupled method of Atom Trap and Mass Spectrometer. It consists of three parts, neutral atom trap, ionization and mass spectrometer. In this paper, we present the demonstration of the magneto-optical trap of neutral calcium. We discuss the isotope selective characteristics of the MOT (Magneto Optical Trap) of calcium by the fluorescence measurement. In addition, the frequency stabilization of the trap beam will be presented

Miniature and micro mass spectrometry for nanoscale sensing applications

International Nuclear Information System (INIS)

Taylor, S; France, N

2009-01-01

In recent years the use of miniature and/or microscale versions of the more popular mass spectrometers have been realised. This has led to the development of portable analytical devices for a range of 'in the field' sensing applications in aerospace, environmental monitoring, medical diagnosis and process control. In this paper the principles underpinning the development of miniature quadrupole mass spectrometers are reviewed. Two different microfabrication methods are compared with a conventional QMS used for residual gas analysis in the range 1-100 Da.

Metabolomic approaches for orange origin discrimination by ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry.

Science.gov (United States)

Díaz, Ramon; Pozo, Oscar J; Sancho, Juan V; Hernández, Félix

2014-08-15

In this work, hybrid quadrupole time-of-flight mass spectrometer (QTOF MS) coupled to ultra high performance liquid chromatography (UHPLC) has been used for biomarkers identification for correct authentication of Valencia (Spain) oranges. Differentiation from foreign Argentinean, Brazilian and South African oranges has been carried out using XCMS application and multivariate analysis to UHPLC-(Q)TOF MS data acquired in both, positive and negative ionisation modes. Several markers have been found and corroborated by analysing two seasons samples. A seasonal independent marker was found and its structure elucidated using accurate mass data and MS(E) fragmentation spectrum information. Empirical formula was searched in Reaxys database applying sub-structure filtering from the fragments obtained. Three possible structures were found and citrusin D, a compound present in sweet oranges, has been identified as the most plausible as it fits better with the product ion scan performed for this compound. As a result of data obtained in this work, citrusin D is suggested as a potential marker to distinguish the geographic origin of oranges. Copyright © 2014 Elsevier Ltd. All rights reserved.

Assessment of benzophenone-4 reactivity with free chlorine by liquid chromatography quadrupole time-of-flight mass spectrometry.

Science.gov (United States)

Negreira, N; Rodríguez, I; Rodil, R; Cela, R

2012-09-19

The stability of the UV filter benzophenone-4 (BP-4) in free chlorine-containing water was investigated, for the first time, by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QqTOF-MS). High mass accuracy and resolution capabilities of this hybrid mass spectrometer were used for the reliable assignation of empirical formulae and chemical structures of BP-4 derivatives. Time-course profiles of the parent compound and its by-products were simultaneously recorded by direct injection of sample aliquots, after quenching the excess of chlorine, in the LC-QqTOF-MS system. At neutral pHs, in excess of chlorine, BP-4 showed a limited stability fitting a pseudo-first-order degradation kinetics. A noticeable reduction in the half-lives of BP-4 was observed when increasing the sample pH between 6 and 8 units and also in presence of bromide traces. The reaction pathway of this UV filter involved a first electrophilic substitution of hydrogen per chlorine (or bromide) in the phenolic ring, followed by oxidation of the carbonyl moiety to an ester group, which induced a further electrophilic substitution in the same aromatic ring. Above reactions were also noticed when mixing a BP-4 containing personal care product with chlorinated tap water and in chlorinated swimming pool and sewage water, previously spiked with a BP-4 standard. Copyright © 2012 Elsevier B.V. All rights reserved.

Double-arm time-of-flight mass-spectrometer of nuclear fragments

International Nuclear Information System (INIS)

Ajvazian, G.M.; Astabatyan, R.A.

1995-01-01

A double-arm time-of-flight spectrometer of nuclear fragments for the investigation of heavy nuclei photofission in the intermediate energy range is described. The calibration results and working characteristics of the spectrometer, obtained using 252 Cf as a source of spontaneous fission, are presented. A mass resolution of σ m ∼2-3 a.m.u. was obtained within the registered fragments mass range of 80-160 a.m.u. The spectrometer was tested in the experiment on the investigation of 238 U nuclei fission by Bremsstahlung photons with Eγ max=1.75 GeV

Inhomogeneous oscillatory electric field time-of-flight mass spectrometer

International Nuclear Information System (INIS)

Carrico, J.P.

1977-01-01

The mass-to-charge ratio of an ion can be determined from the measurement of its flight time in an inhomogeneous, oscillatory electric field produced by the potential distribution V(x, y, t) = Vsub(DC) + Vsub(AC) cos ωt) (αsub(x)X 2 + αsub(y)Y 2 + αsub(z)Z 2 ). The governing equation of motion is the Mathieu equation. The principle of operation of this novel mass spectrometer is described and results of computer calculations of the flight time and resolution are reported. An experimental apparatus and results and results demonstrating the feasibility of this mass spectrometer principle are described. (author)

Silicon Microleaks for Inlets of Mass Spectrometers

Science.gov (United States)

Harpold, Dan; Hasso, Niemann; Jamieson, Brian G.; Lynch, Bernard A.

2009-01-01

Microleaks for inlets of mass spectrometers used to analyze atmospheric gases can be fabricated in silicon wafers by means of photolithography, etching, and other techniques that are commonly used in the manufacture of integrated circuits and microelectromechanical systems. The microleaks serve to limit the flows of the gases into the mass-spectrometer vacuums to specified very small flow rates consistent with the capacities of the spectrometer vacuum pumps. There is a need to be able to precisely tailor the dimensions of each microleak so as to tailor its conductance to a precise low value. (As used here, "conductance" signifies the ratio between the rate of flow in the leak and the pressure drop from the upstream to the downstream end of the leak.) To date, microleaks have been made, variously, of crimped metal tubes, pulled glass tubes, or frits. Crimped-metal and pulled-glass-tube microleaks cannot readily be fabricated repeatably to precise dimensions and are susceptible to clogging with droplets or particles. Frits tend to be differentially chemically reactive with various gas constituents and, hence, to distort the gas mixtures to be analyzed. The present approach involving microfabrication in silicon largely overcomes the disadvantages of the prior approaches.

Direct mass measurements of neutron-deficient xenon isotopes with the ISOLTRAP mass spectrometer

International Nuclear Information System (INIS)

Dilling, J.; Audi, G.; Beck, D.; Bollen, G.; Henry, S.; Herfurth, F.; Kellerbauer, A.; Kluge, H.-J.; Lunney, D.; Moore, R.B.; Scheidenberger, C.; Schwarz, S.; Sikler, G.; Szerypo, J.

2002-01-01

The masses of Xe isotopes with 124≥A≥114 have been measured using the ISOLTRAP spectrometer at the on-line mass separator ISOLDE/CERN. A mass resolving power of 500 000 was chosen resulting in an accuracy of δm∼12 keV for all isotopes investigated. Conflicts with existing mass data of several standard deviations were found

SSC collider quadrupole cold mass design and development

International Nuclear Information System (INIS)

Farrell, R.A.; Murray, F.S.; Jonas, P.A.; Mischler, W.R.; Blecher, L.

1992-01-01

Approximately 1,664 focussing and defocussing superconducting quadrupoles are required for the two SSC collider rings. Collider quadruple magnets (CQMS) must satisfy stringent performance, reliability, life and low cost criteria. Performance requirements include field uniformity, training, quench, tracking, thermal cycling and alignment. The CQM cold mass design presented incorporates lessons IGC and Alsthom Intermagnetics S.A. (AISA), our joint venture with GEC-Alsthom, learned in the design, development and manufacture of 500 MRI, 160 high-field custom and 126 HERA quadruple superconducting magnets. This baseline design reflects careful quantitative assessment of coil winding placement and collar material, evaluation of field uniformity and mechanical performance of the magnet coil ends using 3-D modeling and analysis, and considers tolerance and process variability. Selected CQM cold mass design highlights and a proposed prototype development program that allows incorporation of test feedback into the design to minimize risk are detailed in this paper. This information may be helpful to SSCL in the design and development of prototype CQM'S

A First Step in the Quest for the Active Constituents in Filipendula ulmaria (Meadowsweet): Comprehensive Phytochemical Identification by Liquid Chromatography Coupled to Quadrupole-Orbitrap Mass Spectrometry.

Science.gov (United States)

Bijttebier, Sebastiaan; Van der Auwera, Anastasia; Voorspoels, Stefan; Noten, Bart; Hermans, Nina; Pieters, Luc; Apers, Sandra

2016-04-01

Filipendula ulmaria (meadowsweet) is traditionally used for the treatment of inflammatory diseases and as a diuretic and antirheumatic. Extracts of Filipendulae herba are on the market in the European Union as food supplements. Nevertheless, its active constituents remain to be revealed. During this study, the phytochemical composition of Filipendulae Ulmariae Herba was comprehensively characterised for the first time with two complementary generic ultrahigh-performance liquid chromatography-photodiode array-accurate mass mass spectrometry methods. Selective ion fragmentation experiments with a hybrid quadrupole-orbital trap mass spectrometer significantly contributed to compound identification: a total of 119 compounds were tentatively identified, 69 new to F. ulmaria. A rich diversity of phenolic constituents was detected and only a few non-phenolic phytochemicals were observed. Metabolisation and pharmacological studies should be conducted to investigate which of these constituents or metabolites there of contribute to the activity of F. ulmaria after oral intake. Georg Thieme Verlag KG Stuttgart · New York.

Laser ablation synthesis of arsenic-phosphide Asm Pn clusters from As-P mixtures. Laser desorption ionisation with quadrupole ion trap time-of-flight mass spectrometry: The mass spectrometer as a synthesizer.

Science.gov (United States)

Kubáček, Pavel; Prokeš, Lubomír; Pamreddy, Annapurna; Peña-Méndez, Eladia María; Conde, José Elias; Alberti, Milan; Havel, Josef

2018-05-30

Only a few arsenic phosphides are known. A high potential for the generation of new compounds is offered by Laser Ablation Synthesis (LAS) and when Laser Desorption Ionization (LDI) is coupled with simultaneous Time-Of-Flight Mass Spectrometry (TOFMS), immediate identification of the clusters can be achieved. LAS was used for the generation of arsenic phosphides via laser ablation of phosphorus-arsenic mixtures while quadrupole ion trap time-of-flight mass spectrometry (QIT-TOFMS) was used to acquire the mass spectra. Many new As m P n ± clusters (479 binary and 369 mono-elemental) not yet described in the literature were generated in the gas phase and their stoichiometry determined. The likely structures for some of the observed clusters arbitrary selected (20) were computed by density functional theory (DFT) optimization. LAS is an advantageous approach for the generation of new As m P n clusters, while mass spectrometry was found to be an efficient technique for the determination of cluster stoichiometry. The results achieved might inspire the synthesis of new materials. Copyright © 2018 John Wiley & Sons, Ltd.

Respiratory mass spectrometer

Energy Technology Data Exchange (ETDEWEB)

Mostert, J.W. (Pretoria Univ. (South Africa). Dept. of Anesthesiology)

1983-06-01

The high degree of technical perfection of the respiratory mass spectrometer has rendered the instrument feasible for routine monitoring of anesthetized patients. It is proposed that the difference between inspired and expired oxygen tension in mm Hg be equated with whole body oxygen consumption in ml/min/M/sup 2/ body-surface area at STPD, by the expedient of multiplying tension-differences by a factor of 2. Years of experience have confirmed the value of promptly recognizing sudden drops in this l/E tension difference below 50 mm Hg indicative of metabolic injury from hypovolemia or respiratory depression. Rises in l/E tension-differences were associated with shivering as well as voluntary muscle activity. Tension differences of less than 25 mm Hg (equated with a whole-body O/sub 2/ consumption of less than 50 ml O/sub 2//min/M/sup 2/) occurred in a patient in the sitting position for posterior fossa exploration without acidosis, hypoxia or hypotension for several hours prior to irreversible cardiac arrest. The value of clinical monitoring by mass spectrometry is especially impressive in open-heart surgery.

Eddy covariance emission and deposition flux measurements using proton transfer reaction – time of flight – mass spectrometry (PTR-TOF-MS): comparison with PTR-MS measured vertical gradients and fluxes

NARCIS (Netherlands)

Park, J.H.; Goldstein, A.H.; Timkovsky, J|info:eu-repo/dai/nl/330541676; Fares, S.; Weber, R.; Karlik, J.; Holzinger, R.|info:eu-repo/dai/nl/337989338

2013-01-01

During summer 2010, a proton transfer reaction – time of flight – mass spectrometer (PTR-TOF-MS) and a quadrupole proton transfer reaction mass spectrometer (PTR-MS) were deployed simultaneously for one month in an orange orchard in the Central Valley of California to collect continuous data

Evaluating the accuracy of uranium isotope amount ratio measurements performed by a quadrupole and a multi-collector magnetic sector inductively coupled plasma mass spectrometers for nuclear safeguards

International Nuclear Information System (INIS)

Pereira de Oliveira, O. Jr.; Sarkis, J.E.S.; Ponzevera, E.; Alonso, A.; De Bolle, W.; Quetel, C.

2008-01-01

The n(U 235 )/n(U 238 ) isotope amount ratio in a set of samples was measured using two modern analytical techniques: quadrupole inductively coupled plasma mass spectrometry (ICP-QMS) and multi-collector magnetic sector inductively coupled plasma mass spectrometry (MC-ICPMS). The measured ratios were compared to the certified ratios provided by the high accuracy gas source mass spectrometry (GSMS). The components of the uncertainty were identified and their contribution to the combined standard uncertainty was estimated using the recommendations of the ISO-GUM guide. The values of the measurement uncertainty and bias were determined and then compared to the International Target Values for Measurement Uncertainties in Safeguarding Nuclear Materials. It appears that only the measurements performed by MC-ICPMS can meet the stringent requirements of international nuclear safeguards. (authors)

Mass spectrometer with two ion sources

International Nuclear Information System (INIS)

Glickman, L.G.; Mit', A.G.

2002-01-01

Static mass spectrometer with mid-plane near which ions are moving is considered in this article. Two ion sources are used, their exit slits are perpendicular to the mid-plane. The simple method of the replacement of source is offered. Two concave two-electrode transaxial mirrors with two-plate electrodes are used for this aim. The mid-plane of these mirrors coincides with the mid-plane of the device. The exit slit of each source is located in the principal plane of the object space. The principal planes of the image space of the both mirrors coincide. The images of the exit slits of the sources are in these planes and coincide too. We used the mirrors making stigmatic images with the magnification one to one, in which the dispersion on energy and spherical aberrations of the second order are equal to zero. These images are the objects on which the ion-optical system of the mass spectrometer is tuned. When you choose one from two ion sources it is enough to switch the corresponding mirror

Gas Chromatic Mass Spectrometer

Science.gov (United States)

Wey, Chowen

1995-01-01

Gas chromatograph/mass spectrometer (GC/MS) used to measure and identify combustion species present in trace concentration. Advanced extractive diagnostic method measures to parts per billion (PPB), as well as differentiates between different types of hydrocarbons. Applicable for petrochemical, waste incinerator, diesel transporation, and electric utility companies in accurately monitoring types of hydrocarbon emissions generated by fuel combustion, in order to meet stricter environmental requirements. Other potential applications include manufacturing processes requiring precise detection of toxic gaseous chemicals, biomedical applications requiring precise identification of accumulative gaseous species, and gas utility operations requiring high-sensitivity leak detection.

21 Tesla Fourier Transform Ion Cyclotron Resonance Mass Spectrometer Greatly Expands Mass Spectrometry Toolbox

Energy Technology Data Exchange (ETDEWEB)

Shaw, Jared B.; Lin, Tzu-Yung; Leach, Franklin E.; Tolmachev, Aleksey V.; Tolić, Nikola; Robinson, Errol W.; Koppenaal, David W.; Paša-Tolić, Ljiljana

2016-10-12

We provide the initial performance evaluation of a 21 Tesla Fourier transform ion cyclotron resonance mass spectrometer operating at the Environmental Molecular Sciences Laboratory at Pacific Northwest National Laboratory. The spectrometer constructed for the 21T system employs a commercial dual linear ion trap mass spectrometer coupled to a FTICR spectrometer designed and built in-house. Performance gains from moving to higher magnetic field strength are exemplified by the measurement of peptide isotopic fine structure, complex natural organic matter mixtures, and large proteins. Accurate determination of isotopic fine structure was demonstrated for doubly charged substance P with minimal spectral averaging, and 8,158 molecular formulas assigned to Suwannee River Fulvic Acid standard with RMS error of 10 ppb. We also demonstrated superior performance for intact proteins; namely, broadband isotopic resolution of the entire charge state distribution of apotransferrin (78 kDa) and facile isotopic resolution of monoclonal antibody under a variety of acquisition parameters (e.g. 6 s time-domains with absorption mode processing yielded resolution of approximately 1M at m/z =2,700).

Characterisation of nuclear fuel samples by quadrupole and multi-collector inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Wernli, Beath; Guenther-Leopold, Ines; Kobler Waldis, Judith; Kopajtic, Zlatan

2003-01-01

The characterisation of nuclear fuel cycle materials for trace and minor metallic constituents is of great interest for the nuclear industry and safeguard officials. The main objective of various international programmes dealing with postirradiation examinations is to improve the knowledge of the inventories of actinides, fission and spallation products in spent nuclear fuels. The low detection limits for a large number of elements combined with the ability to analyse the isotopic composition of the elements have established inductively coupled plasma mass spectrometry (ICP-MS) as a powerful multi-element technique in diverse analytical applications for the characterisation of nuclear materials. Because numerous isobaric overlaps restrict the direct determination of many fission products by mass spectrometry, extensive chemical separations are required for these elements. In order to simplify this sample preparation procedure, a high performance liquid chromatography system (HPLC) was online coupled to the mass spectrometer. Since about 10 years a quadrupole based ICP-MS (Q-ICP-MS) combined with an HPLC is used within the Hot Laboratory of the Paul Scherrer Institut for different applications on nuclear fuel samples. Since May 2003 also a new multi-collector ICP-MS (MC-ICP-MS) is used for the mass spectrometric characterisation of nuclear fuel samples, especially for the precise determination of the isotopic vectors of fission products and actinides. Therefore, two complementary analytical systems are now available in the group of 'Isotope and Wet Analytical Chemistry'. A comparison of the analytical performance of both systems (with and without an online coupled HPLC system) for the determination of the isotopic composition and the elemental concentration of different nuclides in nuclear fuel samples, the advantages and limitations of both techniques, the accuracy and precision of the results and typical applications for both methods will be discussed in the

Development and testing of a double-focusing, static, axisymmetric mass spectrometer

International Nuclear Information System (INIS)

Ritter, G.

1979-04-01

The developed mass spectrometer affords very high acceptance (cm 2 sr) compared with conventional mass spectrometers owing to its large solid angle of 0.178 sr. The ion optical properties of the instrument were tested by bombarding various targets (Al, Ni, Ti, Cu, Si) with potassium or caesium ions from a thermionic ion source with energies of 1, 2 and 3 keV and recording mass spectra of positive and negative sputtered ions. The ion optical beam path was calculated analytically (magnet system) in part and numerically in part (energy analyzer, einzel lenses and detector system) and represented in graph form. The results obtained from the mass spectra showed that the magnet system with its twelve permanent magnets is too irregular to produce mass linses with good resolution. Furthermore, it was found that the maximum primary energy of the alkali ions that was possible in this mass spectrometer owing to the breakdown strength was not sufficient to record surface-specific mass spectra since the target surface was covered within a very short time with an at least monatomic layer of alkali ions from the thermionic ion source. (orig./HP) [de

The Laser Ablation Ion Funnel: Sampling for in situ Mass Spectrometry on Mars

Science.gov (United States)

Johnson, Paul V.; Hodyss, Robert; Tang, Keqi; Brinckerhoff, William B.; Smith, Richard D.

2011-01-01

A considerable investment has been made by NASA and other space agencies to develop instrumentation suitable for in situ analytical investigation of extra terrestrial bodies including various mass spectrometers (time-of-flight, quadrupole ion trap, quadrupole mass filters, etc.). However, the front-end sample handling that is needed to collect and prepare samples for interrogation by such instrumentation remains underdeveloped. Here we describe a novel approach tailored to the exploration of Mars where ions are created in the ambient atmosphere via laser ablation and then efficiently transported into a mass spectrometer for in situ analysis using an electrodynamic ion funnel. This concept would enable elemental and isotopic analysis of geological samples with the analysis of desorbed organic material a possibility as well. Such an instrument would be suitable for inclusion on all potential missions currently being considered such as the Mid-Range Rover, the Astrobiology Field Laboratory, and Mars Sample Return (i.e., as a sample pre-selection triage instrument), among others.

Lead isotope ratio analysis of bullet samples by using quadrupole ICP-MS

International Nuclear Information System (INIS)

Tamura, Shu-ichi; Hokura, Akiko; Nakai, Izumi; Oishi, Masahiro

2006-01-01

The measurement conditions for the precise analysis of the lead stable isotope ratio by using an ICP-MS equipped with a quadrupole mass spectrometer were studied in order to apply the technique to the forensic identification of bullet samples. The values of the relative standard deviation obtained for the ratio of 208 Pb/ 206 Pb, 207 Pb/ 206 Pb and 204 Pb/ 206 Pb were lower than 0.2% after optimization of the analytical conditions, including the optimum lead concentration of the sample solution to be about 70 ppb and an integration time for 1 m/s of 15 s. This method was applied to an analysis of lead in bullets for rifles and handguns; a stable isotope ratio of lead was found to be suitable for the identification of bullets. This study has demonstrated that the lead isotope ratio measured by using a quadrupole ICP-MS was useful for a practical analysis of bullet samples in forensic science. (author)

Performance results of a mobile high-resolution MR-TOF mass spectrometer for in-situ analytical mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Lippert, Wayne; Lang, Johannes [Justus-Liebig-Universitaet Giessen (Germany); Ayet San Andres, Samuel [GSI, Darmstadt (Germany); Dickel, Timo; Geissel, Hans; Plass, Wolfgang; Scheidenberger, Christoph [Justus-Liebig-Universitaet Giessen (Germany); GSI, Darmstadt (Germany); Yavor, Mikhail [RAS St. Petersburg (Russian Federation)

2014-07-01

A mobile multiple-reflection time-of-flight mass spectrometer (MR-TOF-MS) has been developed which provides a mass resolving power exceeding 250,000 and sub-ppm mass accuracy in a transportable format. Thus it allows resolving isobars and enables accurate determination of the composition and structure of biomolecules. Furthermore the device offers high mass resolving MS/MS capability via selective ion re-trapping and collisional-induced dissociation (CID). An atmospheric pressure interface (API) provides for routine measurements with various atmospheric ion sources. All supply electronics, DAQ and control system are mounted with the spectrometer into a single frame with a total volume of only 0.8 m{sup 3}. With the current system many applications like waste water monitoring at hot spots, mass-based classification of biomolecules and breath analysis are possible. In addition the mass spectrometer is readily scalable and can be adopted and simplified for even more specific use like in space science for instance. A characterization and first performance results are shown, and the implementation of MS/MS in combination with CID is discussed.

An improved data acquisition system for isotopic ratio mass spectrometers

International Nuclear Information System (INIS)

Saha, T.K.; Reddy, B.; Nazare, C.K.; Handu, V.K.

1999-01-01

Isotopic ratio mass spectrometers designed and fabricated to measure the isotopic ratios with a precision of better than 0.05%. In order to achieve this precision, the measurement system consisting of ion signal to voltage converters, analog to digital converters, and data acquisition electronics should be at least one order better than the overall precision of measurement. Using state of the art components and techniques, a data acquisition system, which is an improved version of the earlier system, has been designed and developed for use with multi-collector isotopic ratio mass spectrometers

Quantitative determination of carbonaceous particle mixing state in Paris using single particle mass spectrometer and aerosol mass spectrometer measurements

Science.gov (United States)

Healy, R. M.; Sciare, J.; Poulain, L.; Crippa, M.; Wiedensohler, A.; Prévôt, A. S. H.; Baltensperger, U.; Sarda-Estève, R.; McGuire, M. L.; Jeong, C.-H.; McGillicuddy, E.; O'Connor, I. P.; Sodeau, J. R.; Evans, G. J.; Wenger, J. C.

2013-04-01

Single particle mixing state information can be a powerful tool for assessing the relative impact of local and regional sources of ambient particulate matter in urban environments. However, quantitative mixing state data are challenging to obtain using single particle mass spectrometers. In this study, the quantitative chemical composition of carbonaceous single particles has been estimated using an aerosol time-of-flight mass spectrometer (ATOFMS) as part of the MEGAPOLI 2010 winter campaign in Paris, France. Relative peak areas of marker ions for elemental carbon (EC), organic aerosol (OA), ammonium, nitrate, sulphate and potassium were compared with concurrent measurements from an Aerodyne high resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS), a thermal/optical OCEC analyser and a particle into liquid sampler coupled with ion chromatography (PILS-IC). ATOFMS-derived mass concentrations reproduced the variability of these species well (R2 = 0.67-0.78), and ten discrete mixing states for carbonaceous particles were identified and quantified. Potassium content was used to identify particles associated with biomass combustion. The chemical mixing state of HR-ToF-AMS organic aerosol factors, resolved using positive matrix factorization, was also investigated through comparison with the ATOFMS dataset. The results indicate that hydrocarbon-like OA (HOA) detected in Paris is associated with two EC-rich mixing states which differ in their relative sulphate content, while fresh biomass burning OA (BBOA) is associated with two mixing states which differ significantly in their OA/EC ratios. Aged biomass burning OA (OOA2-BBOA) was found to be significantly internally mixed with nitrate, while secondary, oxidized OA (OOA) was associated with five particle mixing states, each exhibiting different relative secondary inorganic ion content. Externally mixed secondary organic aerosol was not observed. These findings demonstrate the heterogeneity of primary and

Quantitative determination of carbonaceous particle mixing state in Paris using single-particle mass spectrometer and aerosol mass spectrometer measurements

Directory of Open Access Journals (Sweden)

R. M. Healy

2013-09-01

Full Text Available Single-particle mixing state information can be a powerful tool for assessing the relative impact of local and regional sources of ambient particulate matter in urban environments. However, quantitative mixing state data are challenging to obtain using single-particle mass spectrometers. In this study, the quantitative chemical composition of carbonaceous single particles has been determined using an aerosol time-of-flight mass spectrometer (ATOFMS as part of the MEGAPOLI 2010 winter campaign in Paris, France. Relative peak areas of marker ions for elemental carbon (EC, organic aerosol (OA, ammonium, nitrate, sulfate and potassium were compared with concurrent measurements from an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS, a thermal–optical OCEC analyser and a particle into liquid sampler coupled with ion chromatography (PILS-IC. ATOFMS-derived estimated mass concentrations reproduced the variability of these species well (R2 = 0.67–0.78, and 10 discrete mixing states for carbonaceous particles were identified and quantified. The chemical mixing state of HR-ToF-AMS organic aerosol factors, resolved using positive matrix factorisation, was also investigated through comparison with the ATOFMS dataset. The results indicate that hydrocarbon-like OA (HOA detected in Paris is associated with two EC-rich mixing states which differ in their relative sulfate content, while fresh biomass burning OA (BBOA is associated with two mixing states which differ significantly in their OA / EC ratios. Aged biomass burning OA (OOA2-BBOA was found to be significantly internally mixed with nitrate, while secondary, oxidised OA (OOA was associated with five particle mixing states, each exhibiting different relative secondary inorganic ion content. Externally mixed secondary organic aerosol was not observed. These findings demonstrate the range of primary and secondary organic aerosol mixing states in Paris. Examination of the

Quantitative determination of carbonaceous particle mixing state in Paris using single-particle mass spectrometer and aerosol mass spectrometer measurements

Science.gov (United States)

Healy, R. M.; Sciare, J.; Poulain, L.; Crippa, M.; Wiedensohler, A.; Prévôt, A. S. H.; Baltensperger, U.; Sarda-Estève, R.; McGuire, M. L.; Jeong, C.-H.; McGillicuddy, E.; O'Connor, I. P.; Sodeau, J. R.; Evans, G. J.; Wenger, J. C.

2013-09-01

Single-particle mixing state information can be a powerful tool for assessing the relative impact of local and regional sources of ambient particulate matter in urban environments. However, quantitative mixing state data are challenging to obtain using single-particle mass spectrometers. In this study, the quantitative chemical composition of carbonaceous single particles has been determined using an aerosol time-of-flight mass spectrometer (ATOFMS) as part of the MEGAPOLI 2010 winter campaign in Paris, France. Relative peak areas of marker ions for elemental carbon (EC), organic aerosol (OA), ammonium, nitrate, sulfate and potassium were compared with concurrent measurements from an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS), a thermal-optical OCEC analyser and a particle into liquid sampler coupled with ion chromatography (PILS-IC). ATOFMS-derived estimated mass concentrations reproduced the variability of these species well (R2 = 0.67-0.78), and 10 discrete mixing states for carbonaceous particles were identified and quantified. The chemical mixing state of HR-ToF-AMS organic aerosol factors, resolved using positive matrix factorisation, was also investigated through comparison with the ATOFMS dataset. The results indicate that hydrocarbon-like OA (HOA) detected in Paris is associated with two EC-rich mixing states which differ in their relative sulfate content, while fresh biomass burning OA (BBOA) is associated with two mixing states which differ significantly in their OA / EC ratios. Aged biomass burning OA (OOA2-BBOA) was found to be significantly internally mixed with nitrate, while secondary, oxidised OA (OOA) was associated with five particle mixing states, each exhibiting different relative secondary inorganic ion content. Externally mixed secondary organic aerosol was not observed. These findings demonstrate the range of primary and secondary organic aerosol mixing states in Paris. Examination of the temporal

Mass-spectrometric measurements for nuclear safeguards

International Nuclear Information System (INIS)

Carter, J.A.; Smith, D.H.; Walker, R.L.

1982-01-01

The need of an on-site inspection device to provide isotopic ratio measurements led to the development of a quadrupole mass spectrometer mounted in a van. This mobile laboratory has the ability, through the use of the resin bead technique, to acquire, prepare, and analyze samples of interest to nuclear safeguards. Precision of the measurements is about 1 to 2%

Matrix-assisted laser desorption/ionization coupled with quadrupole/orthogonal acceleration time-of-flight mass spectrometry for protein discovery, identification, and structural analysis.

Science.gov (United States)

Baldwin, M A; Medzihradszky, K F; Lock, C M; Fisher, B; Settineri, T A; Burlingame, A L

2001-04-15

The design and operation of a novel UV-MALDI ionization source on a commercial QqoaTOF mass spectrometer (Applied Biosystem/MDS Sciex QSTAR Pulsar) is described. Samples are loaded on a 96-well target plate, the movement of which is under software control and can be readily automated. Unlike conventional high-energy MALDI-TOF, the ions are produced with low energies (5-10 eV) in a region of relatively low vacuum (8 mTorr). Thus, they are cooled by extensive low-energy collisions before selection in the quadrupole mass analyzer (Q1), potentially giving a quasi-continuous ion beam ideally suited to the oaTOF used for mass analysis of the fragment ions, although ion yields from individual laser shots may vary widely. Ion dissociation is induced by collisions with argon in an rf-only quadrupole cell, giving typical low-energy CID spectra for protonated peptide ions. Ions separated in the oaTOF are registered by a four-anode detector and time-to-digital converter and accumulated in "bins" that are 625 ps wide. Peak shapes depend upon the number of ion counts in adjacent bins. As expected, the accuracy of mass measurement is shown to be dependent upon the number of ions recorded for a particular peak. With internal calibration, mass accuracy better than 10 ppm is attainable for peaks that contain sufficient ions to give well-defined Gaussian profiles. By virtue of its high resolution, capability for accurate mass measurements, and sensitivity in the low-femotomole range, this instrument is ideally suited to protein identification for proteomic applications by generation of peptide tags, manual sequence interpretation, identification of modifications such as phosphorylation, and protein structural elucidation. Unlike the multiply charged ions typical of electrospray ionization, the singly charged MALDI-generated peptide ions show a linear dependence of optimal collision energy upon molecular mass, which is advantageous for automated operation. It is shown that the novel

Photoionization mass spectrometer for studies of flame chemistry with a synchrotron light source

International Nuclear Information System (INIS)

Cool, Terrill A.; McIlroy, Andrew; Qi, Fei; Westmoreland, Phillip R.; Poisson, Lionel; Peterka, Darcy S.; Ahmed, Musahid

2005-01-01

A flame-sampling molecular-beam photoionization mass spectrometer, recently designed and constructed for use with a synchrotron-radiation light source, provides significant improvements over previous molecular-beam mass spectrometers that have employed either electron-impact ionization or vacuum ultraviolet laser photoionization. These include superior signal-to-noise ratio, soft ionization, and photon energies easily and precisely tunable [E/ΔE(FWHM)≅250-400] over the 7.8-17-eV range required for quantitative measurements of the concentrations and isomeric compositions of flame species. Mass resolution of the time-of-flight mass spectrometer is m/Δm=400 and sensitivity reaches ppm levels. The design of the instrument and its advantages for studies of flame chemistry are discussed

Study of extraterrestrial material by means of a high sensitive mass spectrometer, 1

International Nuclear Information System (INIS)

Arai, O.; Kaneko, K.; Kobayashi, K.; Shimamura, T.

1975-01-01

In this report it is described about a high sensitive mass spectrometer for measurement of isotopic abundance of extraterrestrial material. Detecting isotopic anomalies in extraterrestrial matter induced by cosmic ray or solar wind irradiation, we can obtain many informations about interplanetary and/or intersteller space. For this purpose we reform the mass spectrometer of Low Energy Physics Division of INS to improve the sensitivity and the resolution. In section I--VI some improvements of the mass spectrometer (vacuum system, ion source, collector etc.) are described. In section VII--X newly developed ion counting system is discussed. (auth.)

Highly informative multiclass profiling of lipids by ultra-high performance liquid chromatography - Low resolution (quadrupole) mass spectrometry by using electrospray ionization and atmospheric pressure chemical ionization interfaces.

Science.gov (United States)

Beccaria, Marco; Inferrera, Veronica; Rigano, Francesca; Gorynski, Krzysztof; Purcaro, Giorgia; Pawliszyn, Janusz; Dugo, Paola; Mondello, Luigi

2017-08-04

A simple, fast, and versatile method, using an ultra-high performance liquid chromatography system coupled with a low resolution (single quadrupole) mass spectrometer was optimized to perform multiclass lipid profiling of human plasma. Particular attention was made to develop a method suitable for both electrospray ionization and atmospheric pressure chemical ionization interfaces (sequentially in positive- and negative-ion mode), without any modification of the chromatographic conditions (mobile phase, flow-rate, gradient, etc.). Emphasis was given to the extrapolation of the structural information based on the fragmentation pattern obtained using atmospheric pressure chemical ionization interface, under each different ionization condition, highlighting the complementary information obtained using the electrospray ionization interface, of support for related molecule ions identification. Furthermore, mass spectra of phosphatidylserine and phosphatidylinositol obtained using the atmospheric pressure chemical ionization interface are reported and discussed for the first time. Copyright © 2017 Elsevier B.V. All rights reserved.

Analysis of psychoactive substances in water by information dependent acquisition on a hybrid quadrupole time-of-flight mass spectrometer.

Science.gov (United States)

Andrés-Costa, María Jesús; Andreu, Vicente; Picó, Yolanda

2016-08-26

Emerging drugs of abuse, belonging to many different chemical classes, are attracting users with promises of "legal" highs and easy access via internet. Prevalence of their consumption and abuse through wastewater-based epidemiology can only be realized if a suitable analytical screening procedure exists to detect and quantify them in water. Solid-phase extraction and ultra-high performance liquid chromatography quadrupole time-of-flight-mass spectrometry (UHPLC-QqTOF-MS/MS) was applied for rapid suspect screening as well as for the quantitative determination of 42 illicit drugs and metabolites in water. Using this platform, we were able to identify amphetamines, tryptamines, piperazines, pyrrolidinophenones, arylcyclohexylamines, cocainics, opioids and cannabinoids. Additionally, paracetamol, carbamazepine, ibersartan, valsartan, sulfamethoxazole, terbumeton, diuron, etc. (including degradation products as 3-hydroxy carbamazepine or deethylterbuthylazine) were detected. This method encompasses easy sample preparation and rapid identification of psychoactive drugs against a database that cover more than 2000 compounds that ionized in positive mode, and possibility to identify metabolites and degradation products as well as unknown compounds. The method for river water, influent and effluents samples was fully validated for the target psychoactive substances including assessment of matrix effects (-88-67.8%), recovery (42-115%), precision (psychoactive drugs biomarkers and other water contaminants is demonstrated. Copyright © 2016 Elsevier B.V. All rights reserved.

Quantification of 2'-deoxy-2'-β-fluoro-4'-azidocytidine in rat and dog plasma using liquid chromatography-quadrupole time-of-flight and liquid chromatography-triple quadrupole mass spectrometry: Application to bioavailability and pharmacokinetic studies.

Science.gov (United States)

Peng, Youmei; Cheng, Tiefeng; Dong, Lihong; Zhang, Yuhai; Chen, Xiaojing; Jiang, Jinhua; Zhang, Jingmin; Guo, Xiaohe; Guo, Mintong; Chang, Junbiao; Wang, Qingduan

2014-09-01

2'-Deoxy-2'-β-fluoro-4'-azidocytidine (FNC) is a novel pyrimidine analog that inhibits not only the replication of the hepatitis B virus (HBV), hepatitis C virus (HCV) and HIV but also the replication of lamivudine-resistant HBV, 4'-azidocytidine or 2'-β-methylcytidine-resistant HCV, and nucleoside reverse-transcriptase inhibitor-resistant HIV variants. The present study was undertaken to evaluate the absolute oral bioavailability of FNC in rats and the pharmacokinetic properties of FNC after intragastric administration of single and multiple doses in rats and dogs. A sensitive high-performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (HPLC/Q-TOF MS) method and a reliable high-performance liquid chromatography tandem triple quadrupole mass spectrometry (HPLC/QqQ MS/MS) method were established for the determination of FNC in the rat and dog plasmas, respectively. The sample preparation involved a protein-precipitation method with methanol after the addition of lamivudine as an internal standard. FNC was analyzed by LC using a YMC-Pack Pro C18 column (150mm×4.6mm, 3μm) with methanol (containing 0.3% formic acid): 10mM ammonium acetate (containing 0.3% formic acid, pH 2.8) (35:65, v/v) as the mobile phase. Both mass spectrometers were equipped with an electrospray ionization interface in the positive-ion mode. The linear range was from 2.00 to 2000.00ngmL(-1) in rat plasma and 0.50 to 400.00ngmL(-1) in dog plasma. The intraday and interday precision were less than 10.55%, and the accuracy was in the range of -5.86 to 5.13%. The mean recoveries were greater than 82.70% and 82.97% for FNC and IS, respectively. The HPLC/Q-TOF MS and HPLC/QqQ MS/MS methods were both successfully applied in the pharmacokinetic studies of FNC in rats and dogs. Copyright © 2014 Elsevier B.V. All rights reserved.

Data acquisition and processing system for a mass-spectrometer's site

International Nuclear Information System (INIS)

Kiselev, A.V.; Loginov, N.D.; Marusev, V.I.; Sviridova, Yu.F.; Temnoeva, T.A.; Fedorov, Yu.D.

1986-01-01

A two-level measuring-calculating system (MCS) has been developed; BESM-6 computer is used as a central computer at the upper level, at the lower - a terminal computer of the RPT type (Videoton, Hungary). MCS is designed for: the experimental data acquisition in the RPT immediate memory from several (up to five) mass spectrometers; communication of data accumulated in BESM-6 through a communication link; mathematical processing by BESM-6 and obtaining results at the mass spectrometer region. Simultaneous and independent recording of data from a mass spectrometer group as well as communication of data accumulated in BESM-6 without disturbance of RPT operating mode are provided with specially developed programs executed in RPT under OC RPS control. BESM-6 software is based on basic possibilities of OC RPS with respect to work with terminals. Received data is entered the archive in the form of variable length files by means of direct access programs; such archive organization permits to use the data for subsequent analysis and processing with the help of programs using any level languages

A field portable mass spectrometer for monitoring organic vapors.

Science.gov (United States)

Meier, R W

1978-03-01

A portable mass spectrometer has been designed and built under the sponsorship of the US Army for the purpose of monitoring low concentrations of specified organics in the ambient atmosphere. The goals of the development were discrimination, sensitivity, portability, simplicity of operation, economy and convenience. These objectives were met in a system consisting of a computer operated mass spectrometer with a Llewellyn membrane separator inlet system housed in two 26 x 18 x 9 inch aluminum cases with a total weight less than 150 pounds. This system has shown the capability for field detection of hundreds of specific organic vapors at the parts per billion level in the ambient and workplace environments.

SIEMENS ADVANCED QUANTRA FTICR MASS SPECTROMETER FOR ULTRA HIGH RESOLUTION AT LOW MASS

Energy Technology Data Exchange (ETDEWEB)

Spencer, W; Laura Tovo, L

2008-07-08

The Siemens Advanced Quantra Fourier Transform Ion Cyclotron Resonance (FTICR) mass spectrometer was evaluated as an alternative instrument to large double focusing mass spectrometers for gas analysis. High resolution mass spectrometers capable of resolving the common mass isomers of the hydrogen isotopes are used to provide data for accurate loading of reservoirs and to monitor separation of tritium, deuterium, and helium. Conventional double focusing magnetic sector instruments have a resolution that is limited to about 5000. The Siemens FTICR instrument achieves resolution beyond 400,000 and could possibly resolve the tritium ion from the helium-3 ion, which differ by the weight of an electron, 0.00549 amu. Working with Y-12 and LANL, SRNL requested Siemens to modify their commercial Quantra system for low mass analysis. To achieve the required performance, Siemens had to increase the available waveform operating frequency from 5 MHz to 40 MHz and completely redesign the control electronics and software. However, they were able to use the previous ion trap, magnet, passive pump, and piezo-electric pulsed inlet valve design. NNSA invested $1M in this project and acquired four systems, two for Y-12 and one each for SRNL and LANL. Siemens claimed a $10M investment in the Quantra systems. The new Siemens Advanced Quantra demonstrated phenomenal resolution in the low mass range. Resolution greater than 400,000 was achieved for mass 2. The new spectrometer had a useful working mass range to 500 Daltons. However, experiments found that a continuous single scan from low mass to high was not possible. Two useful working ranges were established covering masses 1 to 6 and masses 12 to 500 for our studies. A compromise performance condition enabled masses 1 to 45 to be surveyed. The instrument was found to have a dynamic range of about three orders of magnitude and quantitative analysis is expected to be limited to around 5 percent without using complex fitting algorithms

AI mass spectrometers for space shuttle health monitoring

Science.gov (United States)

Adams, F. W.

1991-01-01

The facility Hazardous Gas Detection System (HGDS) at Kennedy Space Center (KSC) is a mass spectrometer based gas analyzer. Two instruments make up the HGDS, which is installed in a prime/backup arrangement, with the option of using both analyzers on the same sample line, or on two different lines simultaneously. It is used for monitoring the Shuttle during fuel loading, countdown, and drainback, if necessary. The use of complex instruments, operated over many shifts, has caused problems in tracking the status of the ground support equipment (GSE) and the vehicle. A requirement for overall system reliability has been a major force in the development of Shuttle GSE, and is the ultimate driver in the choice to pursue artificial intelligence (AI) techniques for Shuttle and Advanced Launch System (ALS) mass spectrometer systems. Shuttle applications of AI are detailed.

The application of headspace gas chromatography coupled to tandem quadrupole mass spectrometry for the analysis of furan in baby food samples.

Science.gov (United States)

Pugajeva, Iveta; Rozentale, Irina; Viksna, Arturs; Bartkiene, Elena; Bartkevics, Vadims

2016-12-01

Selective methodology employing a tandem quadrupole mass spectrometer coupled to a gas chromatograph with headspace autosampler (HS-GC-MS/MS) was elaborated in this study. Application of the elaborated procedure resulted in a limit of detection of 0.021μgkg(-1) and a limit of quantification of 0.071μgkg(-1). The mean recoveries during in-house validation ranged from 89% to 109%, and coefficients of variation for repeatability ranged from 4% to 11%. The proposed analytical method was applied for monitoring the furan content of 30 commercial baby food samples available on the Latvian retail market. The level of furan found in these samples varied from 0.45 to 81.9μgkg(-1), indicating that infants whose sole diet comprises baby food sold in jars and cans are exposed constantly to furan. Samples containing vegetables and meat had higher levels of furan than those containing only fruits. Copyright © 2016 Elsevier Ltd. All rights reserved.

A new approach for accurate mass assignment on a multi-turn time-of-flight mass spectrometer.

Science.gov (United States)

Hondo, Toshinobu; Jensen, Kirk R; Aoki, Jun; Toyoda, Michisato

2017-12-01

A simple, effective accurate mass assignment procedure for a time-of-flight mass spectrometer is desirable. External mass calibration using a mass calibration standard together with an internal mass reference (lock mass) is a common technique for mass assignment, however, using polynomial fitting can result in mass-dependent errors. By using the multi-turn time-of-flight mass spectrometer infiTOF-UHV, we were able to obtain multiple time-of-flight data from an ion monitored under several different numbers of laps that was then used to calculate a mass calibration equation. We have developed a data acquisition system that simultaneously monitors spectra at several different lap conditions with on-the-fly centroid determination and scan law estimation, which is a function of acceleration voltage, flight path, and instrumental time delay. Less than 0.9 mDa mass errors were observed for assigned mass to charge ratios ( m/z) ranging between 4 and 134 using only 40 Ar + as a reference. It was also observed that estimating the scan law on-the-fly provides excellent mass drift compensation.

Investigation of cannabis biomarkers and transformation products in waters by liquid chromatography coupled to time of flight and triple quadrupole mass spectrometry.

Science.gov (United States)

Boix, Clara; Ibáñez, María; Bijlsma, Lubertus; Sancho, Juan V; Hernández, Félix

2014-03-01

11-Nor-9-carboxy-Δ(9)-tetrahydrocannabinol (THC-COOH) is commonly selected as biomarker for the investigation of cannabis consumption through wastewater analysis. The removal efficiency of THC-COOH in wastewater treatment plants (WWTPs) has been reported to vary between 31% and 98%. Accordingly, possible transformation products (TPs) of this metabolite might be formed during treatment processes or in receiving surface water under environmental conditions. In this work, surface water was spiked with THC-COOH and subjected to hydrolysis, chlorination and photo-degradation (both ultraviolet and simulated sunlight) experiments under laboratory-controlled conditions. One hydrolysis, eight chlorination, three ultraviolet photo-degradation and seven sunlight photo-degradation TPs were tentatively identified by liquid chromatography coupled to quadrupole time-of-flight mass spectrometer (LC-QTOF MS). In a subsequent step, THC-COOH and the identified TPs were searched in wastewater samples using LC coupled to tandem mass spectrometry (LC-MS/MS) with triple quadrupole. THC-COOH was found in all influent and effluent wastewater samples analyzed, although at significant lower concentrations in the effluent samples. The removal efficiency of WWTP under study was approximately 86%. Furthermore, THC-COOH was also investigated in several surface waters, and it was detected in 50% of the samples analyzed. Regarding TPs, none were found in influent wastewater, while one hydrolysis and five photo-degradation (simulated sunlight) TPs were detected in effluent and surface waters. The most detected compound, resulting from sunlight photo-degradation, was found in 60% of surface waters analyzed. This fact illustrates the importance of investigating these TPs in the aquatic environment. Copyright © 2013 Elsevier Ltd. All rights reserved.

Time-of-flight mass spectrometer

International Nuclear Information System (INIS)

Ivanov, M.A.; Kozlov, B.N.; Mamyrin, B.A.; Shmikk, D.V.; Shebelin, V.G.

1981-01-01

A time-of-flight mass spectrometer containing a pulsed ion source with an electron gun and two electrodes limiting ionization range, drift space and ion acceptor, is described. To expand functional possibilities, a slot collimator of the gas stream, two quantum generators and two diaphragms for the inlet of quantum generator radiation located on both sides of the ion source, are introduced in the ion source. The above invention enables to study details of the complex interaction process of laser radiation with molecules of the gas stream, which is actual for laser isotope separation

FY16 Safeguards Technology Cart-Portable Mass Spectrometer Project Final Report

Energy Technology Data Exchange (ETDEWEB)

Thompson, Cyril V. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Whitten, William B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-02-01

The Oak Ridge National Laboratory project for the Next Generation Safeguards Initiative Safeguards Technology Development Subprogram has been involved in the development of a cart portable mass spectrometer based on a Thermo ITQ ion trap mass spectrometer (referred to simply as the ITQ) for the field analysis of 235U/238U ratios in UF6. A recent discovery of the project was that combining CO2 with UF6 and introducing the mixture to the mass spectrometer (MS) appeared to increase the ionization efficiency and, thus, reduce the amount of UF6 needed for an analysis while also reducing the corrosive effects of the sample. However, initial experimentation indicated that mixing parameters should be closely controlled to ensure reproducible results. To this end, a sample manifold (SM) that would ensure the precise mixing of UF6 and CO2 was designed and constructed. A number of experiments were outlined and conducted to determine optimum MS and SM conditions which would provide the most stable isotope ratio analysis. The principal objective of the project was to provide a retrofit ITQ mass spectrometer operating with a SM capable of achieving a variation in precision of less than 1% over 1 hour of sampling. This goal was achieved by project end with a variation in precision of 0.5 to 0.8% over 1 hour of sampling.

Characterisation of an ion source on the Helix MC Plus noble gas mass spectrometer - pressure dependent mass discrimination

Science.gov (United States)

Zhang, X.

2017-12-01

Characterisation of an ion source on the Helix MC Plusnoble gas mass spectrometer - pressure dependent mass discrimination Xiaodong Zhang* dong.zhang@anu.edu.au Masahiko Honda Masahiko.honda@anu.edu.au Research School of Earth Sciences, The Australian National University, Canberra, Australia To obtain reliable measurements of noble gas elemental and isotopic abundances in a geological sample it is essential that the mass discrimination (instrument-induced isotope fractionation) of the mass spectrometer remain constant over the working range of noble gas partial pressures. It is known, however, that there are pressure-dependent variations in sensitivity and mass discrimination in conventional noble gas mass spectrometers [1, 2, 3]. In this study, we discuss a practical approach to ensuring that the pressure effect in the Helix MC Plus high resolution, multi-collector noble gas mass spectrometer is minimised. The isotopic composition of atmospheric Ar was measured under a range of operating conditions to test the effects of different parameters on Ar mass discrimination. It was found that the optimised ion source conditions for pressure independent mass discrimination for Ar were different from those for maximised Ar sensitivity. The optimisation can be achieved by mainly adjusting the repeller voltage. It is likely that different ion source settings will be required to minimise pressure-dependent mass discrimination for different noble gases. A recommended procedure for tuning an ion source to reduce pressure dependent mass discrimination will be presented. References: Honda M., et al., Geochim. Cosmochim. Acta, 57, 859 -874, 1993. Burnard P. G., and Farley K. A., Geochemistry Geophysics Geosystems, Volume 1, 2000GC00038, 2000. Mabry J., et al., Journal of Analytical Atomic Spectrometry, 27, 1012 - 1017, 2012.

Molecular beam mass spectrometer equipped with a catalytic wall reactor for in situ studies in high temperature catalysis research

International Nuclear Information System (INIS)

Horn, R.; Ihmann, K.; Ihmann, J.; Jentoft, F.C.; Geske, M.; Taha, A.; Pelzer, K.; Schloegl, R.

2006-01-01

A newly developed apparatus combining a molecular beam mass spectrometer and a catalytic wall reactor is described. The setup has been developed for in situ studies of high temperature catalytic reactions (>1000 deg. C), which involve besides surface reactions also gas phase reactions in their mechanism. The goal is to identify gas phase radicals by threshold ionization. A tubular reactor, made from the catalytic material, is positioned in a vacuum chamber. Expansion of the gas through a 100 μm sampling orifice in the reactor wall into differentially pumped nozzle, skimmer, and collimator chambers leads to the formation of a molecular beam. A quadrupole mass spectrometer with electron impact ion source designed for molecular beam inlet and threshold ionization measurements is used as the analyzer. The sampling time from nozzle to detector is estimated to be less than 10 ms. A detection time resolution of up to 20 ms can be reached. The temperature of the reactor is measured by pyrometry. Besides a detailed description of the setup components and the physical background of the method, this article presents measurements showing the performance of the apparatus. After deriving the shape and width of the energy spread of the ionizing electrons from measurements on N 2 and He we estimated the detection limit in threshold ionization measurements using binary mixtures of CO in N 2 to be in the range of several hundreds of ppm. Mass spectra and threshold ionization measurements recorded during catalytic partial oxidation of methane at 1250 deg. C on a Pt catalyst are presented. The detection of CH 3 · radicals is successfully demonstrated

Molecular beam mass spectrometer equipped with a catalytic wall reactor for in situ studies in high temperature catalysis research

Science.gov (United States)

Horn, R.; Ihmann, K.; Ihmann, J.; Jentoft, F. C.; Geske, M.; Taha, A.; Pelzer, K.; Schlögl, R.

2006-05-01

A newly developed apparatus combining a molecular beam mass spectrometer and a catalytic wall reactor is described. The setup has been developed for in situ studies of high temperature catalytic reactions (>1000°C), which involve besides surface reactions also gas phase reactions in their mechanism. The goal is to identify gas phase radicals by threshold ionization. A tubular reactor, made from the catalytic material, is positioned in a vacuum chamber. Expansion of the gas through a 100μm sampling orifice in the reactor wall into differentially pumped nozzle, skimmer, and collimator chambers leads to the formation of a molecular beam. A quadrupole mass spectrometer with electron impact ion source designed for molecular beam inlet and threshold ionization measurements is used as the analyzer. The sampling time from nozzle to detector is estimated to be less than 10ms. A detection time resolution of up to 20ms can be reached. The temperature of the reactor is measured by pyrometry. Besides a detailed description of the setup components and the physical background of the method, this article presents measurements showing the performance of the apparatus. After deriving the shape and width of the energy spread of the ionizing electrons from measurements on N2 and He we estimated the detection limit in threshold ionization measurements using binary mixtures of CO in N2 to be in the range of several hundreds of ppm. Mass spectra and threshold ionization measurements recorded during catalytic partial oxidation of methane at 1250°C on a Pt catalyst are presented. The detection of CH3• radicals is successfully demonstrated.

Quadrupole mass detector in the field of weak plane gravitational waves

International Nuclear Information System (INIS)

Borisova, L.B.

1978-01-01

Studied is the behaviour of the system which consists of two test particles connected by a string (quadrupole mass detector) and placed in the field of weak plane monochromatic gravitational waves. It is shown that at cross orientation of the detector the gravitational wave effecting such a system excites oscillations in it with the frequency equal to that of the gravitational wave source. The role of the driving force is played by the periodical change with the time of the equilibrium position. The gravitational wave does not influence the detector at its longitudinal orientation

Ion optics of a time-of-flight mass spectrometer with electrostatic sector analyzers

International Nuclear Information System (INIS)

Sakurai, T.; Ito, H.; Matsuo, T.

1995-01-01

The ion optics for a high resolution time-of-flight mass spectrometer with electrostatic sector analyzers have been investigated. The multiple focusing (triple isochronous focusing and triple spacial focusing) conditions can be achieved by using a symmetrical arrangement of the sectors in a mass spectrometer. Both high mass resolution and high ion transmission can be accomplished simultaneously. The principles of MS/MS and MS/MS/MS analyses using a TOF mass spectrometer with electrostatic sector analyzers have been proposed. Product ion spectra can be obtained by measuring the total flight times and the kinetic energy of the products without any additional separation processes, any coincidence techniques or any special timing circuits. In an experiment, MS/MS and MS/MS/MS mass spectra have been obtained. The first generation product ions have been produced by a metastable decay, and the second generation products have been produced by a sequential decay. (orig.)

The respiratory mass spectrometer

International Nuclear Information System (INIS)

Mostert, J.W.

1983-01-01

The high degree of technical perfection of the respiratory mass spectrometer has rendered the instrument feasible for routine monitoring of anesthetized patients. It is proposed that the difference between inspired and expired oxygen tension in mm Hg be equated with whole body oxygen consumption in ml/min/M 2 body-surface area at STPD, by the expedient of multiplying tension-differences by a factor of 2. Years of experience have confirmed the value of promptly recognizing sudden drops in this l/E tension difference below 50 mm Hg indicative of metabolic injury from hypovolemia or respiratory depression. Rises in l/E tension-differences were associated with shivering as well as voluntary muscle activity. Tension differences of less than 25 mm Hg (equated with a whole-body O 2 consumption of less than 50 ml O 2 /min/M 2 ) occurred in a patient in the sitting position for posterior fossa exploration without acidosis, hypoxia or hypotension for several hours prior to irreversible cardiac arrest. The value of clinical monitoring by mass spectrometry is especially impressive in open-heart surgery

The History of Planetary Exploration Using Mass Spectrometers

Science.gov (United States)

Mahaffy, Paul R.

2012-01-01

At the Planetary Probe Workshop Dr. Paul Mahaffy will give a tutorial on the history of planetary exploration using mass spectrometers. He will give an introduction to the problems and solutions that arise in making in situ measurements at planetary targets using this instrument class.

Exploring ECD on a Benchtop Q Exactive Orbitrap Mass Spectrometer

DEFF Research Database (Denmark)

Fort, Kyle L; Cramer, Christian N; Voinov, Valery G

2018-01-01

As the application of mass spectrometry intensifies in scope and diversity, the need for advanced instrumentation addressing a wide variety of analytical needs also increases. To this end, many modern, top-end mass spectrometers are designed or modified to include a wider range of fragmentation...... applications including middle-down proteomics, top-down proteomics, glycoproteomics, and disulfide bond mapping. We describe the modification of the popular Q Exactive Orbitrap mass spectrometer to extend its fragmentation capabilities to include ECD. We show that this modification allows ≥85% matched ion...... intensity to originate from ECD fragment ion types as well as provides high sequence coverage (≥60%) of intact proteins and high fragment identification rates with ∼70% of ion signals matched. Finally, the ECD implementation promotes selective disulfide bond dissociation, facilitating the identification...

Miniature Mass Spectrometer for Earth Science Research, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — By drastically reducing the physical footprint of a mass spectrometer to the size of a beverage can, Ceramitron could set a new performance/price standard in the...

A new thermal ionisation mass spectrometer

International Nuclear Information System (INIS)

Haines, C.; Merren, T.O.; Unsworth, W.D.

1979-01-01

The Isomass 54E, a new thermal ionisation mass spectrometer for precise measurements of isotopic composition is described in detail. It combines the fruits of three development pro ects, viz. automation, energy filters and extended geometry with existing micromass expertise and experience. The hardware and software which are used for the automation as well as the energy filter used, are explained. The 'extended geometry' ion optical system adopted for better performance is discussed in detail. (K.B.)

Nuclear quadrupole resonance of arsenolite

International Nuclear Information System (INIS)

Madarazo, R.

1988-01-01

A pulsed Nuclear Quadrupole Resonance (NQR) spectrometer was constructed using imported Matec units. Peripherical components were specially assembled and tested for the implantation of the spin-echo technique in the Laboratorio de Centros de Cor of IFUSP. The R.F. operation range is from 50 to 1 ) and spin-spin (T 2 ) relaxation times were carried out at room temperature in arsenolite. The 75 As NQR frequency measured at room temperature is 116.223 MHz. (author) [pt

Analog and digital dividers for mass spectrometers

International Nuclear Information System (INIS)

Osipov, A.K.

1980-01-01

Errors of four different types of stress dividers used in statical mass-spectrometers for determination of mass number by accelerating stress are analyzed. The simplest flowsheet of the analog divider comprises operation amplifier, in the chain of the negative feedback of which a multiplication device on differential cascade is switched- in. This analog divider has high sensitivity to temperature and high error approximately 5%. Application of the multiplier on differential cascade with normalization permits to increase temperature stability and decrease the error up to 1%. Another type of the analog divider is a logarithmic divider the error of which is constant within the whole operation range and it constitutes 1-5%. The digital divider with a digital-analog transformer (DAT) has the error of +-0.015% which is determined by the error of detectors and resistance of keys in the locked state. Considered is the design of a divider based on transformation of the inlet stress into the time period. The error of the divider is determined in this case mainly by stress of the zero shift of the operation amplifier (it should be compensated) and relative threshold stability of the comparator triggering which equals (2-3)x10 -4 . It is noted that the divider with DAT application and the divider with the use of stress transformation within the time period are most perspective ones for statical mass-spectrometers [ru

Reduction of determinate errors in mass bias-corrected isotope ratios measured using a multi-collector plasma mass spectrometer

International Nuclear Information System (INIS)

Doherty, W.

2015-01-01

A nebulizer-centric instrument response function model of the plasma mass spectrometer was combined with a signal drift model, and the result was used to identify the causes of the non-spectroscopic determinate errors remaining in mass bias-corrected Pb isotope ratios (Tl as internal standard) measured using a multi-collector plasma mass spectrometer. Model calculations, confirmed by measurement, show that the detectable time-dependent errors are a result of the combined effect of signal drift and differences in the coordinates of the Pb and Tl response function maxima (horizontal offset effect). If there are no horizontal offsets, then the mass bias-corrected isotope ratios are approximately constant in time. In the absence of signal drift, the response surface curvature and horizontal offset effects are responsible for proportional errors in the mass bias-corrected isotope ratios. The proportional errors will be different for different analyte isotope ratios and different at every instrument operating point. Consequently, mass bias coefficients calculated using different isotope ratios are not necessarily equal. The error analysis based on the combined model provides strong justification for recommending a three step correction procedure (mass bias correction, drift correction and a proportional error correction, in that order) for isotope ratio measurements using a multi-collector plasma mass spectrometer

Diagnostics of capacitively-coupled hydrocarbon plasmas for deposition of diamond-like carbon films using quadrupole mass spectrometry and Langmuir probe

Science.gov (United States)

Oda, Akinori; Fukai, Shun; Kousaka, Hiroyuki; Ohta, Takayuki

2015-09-01

Diamond-like carbon (DLC) films are the hydrogenated amorphous carbon films, which contains a mixture of sp2- and sp3-bonded carbon. The DLC films have been widely used for various applications, such as automotive, semiconductors, medical devices, since have excellent material properties in lower friction, higher chemical stability, higher hardness, higher wear resistance. Until now, numerous investigations on the DLC films using plasma assisted chemical vapor deposition have been done. For precise control of coating technique of DLC films, it is enormously important to clarify the fundamental properties in hydrocarbon plasmas, as a source of hydrocarbon ions and radicals. In this paper, the fundamental properties in a low pressure radio-frequency hydrocarbon (Ar/CH4 (1 %) gas mixture) plasmas have been diagnosed using a quadrupole mass spectrometer (HIDEN ANARYTICAL Ltd., EQP-300) and Langmuir probe system (HIDEN ANARYTICAL Ltd., ESPion). This work was partly supported by KAKENHI (No.26420247), and a ``Grant for Advanced Industrial Technology Development (No.11B06004d)'' in 2011 from the New Energy and Industrial Technology Development Organization (NEDO) of Japan.

Procedure and apparatus for controlling the ion energy in a mass spectrometer

Energy Technology Data Exchange (ETDEWEB)

Fies, W J; Reeher, J R; Story, M S; Smith, R D

1977-03-03

The invention relates to a process and apparatus for adjusting the energy of ions of different masses in a mass spectrometer. Specifically, it concerns a mass spectrometer having a gas inlet and ionisation space. A multipole mass filter includes several electrodes. A focusing system connects the ionisation space and the mass filter. Provision is made for applying to the electrodes a mass adjusting voltage combining a high frequency voltage and a d.c. voltage of increasing amplitude, so that the ions of a pre-determined mass can be selected. This system also includes a device connected to the electrodes, sensitive to the mass adjusting voltage and enabling the energy of the ions to be adjusted to that of the selected ions, depending on the mass of the ions, by modifying the difference in potential between the ionisation volume and the mean potential of the electrodes .

Ion beam alignment in the MSX-4 mass spectrometer

International Nuclear Information System (INIS)

Busygin, A.I.; Nevzorov, A.A.; Ul'masbaev, B.Sh.

1977-01-01

A method for electrically adjusting an ion beam in an MSKh-4 mass-spectrometer has been developed. The adjusting system consists of two deflecting plates fastened to the frame of the ion source. By adjusting the potential difference at the plates in the range 0-150 v, one can increase the intensity of the mass-spectrum by a factor of 3 to 5

Special features of the isotope ratio determination using mass-spectrometer with induction-bound plasma

International Nuclear Information System (INIS)

Stepanov, A.I.; Ramendik, G.I.; Fatyushina, E.V.

2000-01-01

The origin of the errors arising upon measuring relative abundance of Nd, Yb, and Gd isotopes on a HP-4500 mass-spectrometer (USA) is studied. It is shown that the main origin of the error is the different sensitivity of the mass-spectrometer to ions of different masses. Optimal content of the elements in the solutions is established upon determination of their isotopic abundance [ru

An achromatic multipassage magnetic mass spectrometer

International Nuclear Information System (INIS)

Boulanger, P.; Baril, M.

1999-01-01

A design providing achromatic correction to a multipassage magnetic mass spectrometer previously described by the author is presented. The energy spatial dispersion caused by repeated passages in the magnetic prism is corrected by three supplementary mirrors placed in a reinjection loop. From this study one can see that we simultaneously eliminate the energy dispersion term C ΔE/E and the opening angle aberration term C α 2 and we may also eliminate the coupled aberration term C αΔE/E

Note: A versatile mass spectrometer chamber for molecular beam and temperature programmed desorption experiments

Energy Technology Data Exchange (ETDEWEB)

Tonks, James P., E-mail: james.tonks@awe.co.uk [Department of Mechanical Engineering Sciences, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom); AWE Plc, Aldermaston, Reading, Berkshire RG7 4PR (United Kingdom); Galloway, Ewan C., E-mail: ewan.galloway@awe.co.uk; King, Martin O. [AWE Plc, Aldermaston, Reading, Berkshire RG7 4PR (United Kingdom); Kerherve, Gwilherm [VACGEN Ltd, St. Leonards-On-Sea, East Sussex TN38 9NN (United Kingdom); Watts, John F. [Department of Mechanical Engineering Sciences, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)

2016-08-15

A dual purpose mass spectrometer chamber capable of performing molecular beam scattering (MBS) and temperature programmed desorption (TPD) is detailed. Two simple features of this design allow it to perform these techniques. First, the diameter of entrance aperture to the mass spectrometer can be varied to maximize signal for TPD or to maximize angular resolution for MBS. Second, the mass spectrometer chamber can be radially translated so that it can be positioned close to the sample to maximize signal or far from the sample to maximize angular resolution. The performance of this system is described and compares well with systems designed for only one of these techniques.

Pulsed coherent spectrometer of nuclear magnetic and nuclear quadrupole resonance

International Nuclear Information System (INIS)

Karnachev, A.S.; Solov'ev, E.E.

1996-01-01

The spectrometer intended for studies on solid bodies was created on the basis of the X1-48 device for investigation of amplitude-frequency characteristics with the frequency range of 5-100 MHz, the receiver sensitivity by the signal-noise ratio at the outlet of 12 dB not worse than 0.5 μV and the feed-up capacity up to 80 W. The X1-48 minimal remodeling made it possible to use it in the spectrometer system as a signal feed-up source and measurer of the amplitude-frequency characteristic of the spectrometer receiver tract. 12 refs., 11 figs

Isobar Separation in a Multiple-Reflection Time-of-Flight Mass Spectrometer by Mass-Selective Re-Trapping

Science.gov (United States)

Dickel, Timo; Plaß, Wolfgang R.; Lippert, Wayne; Lang, Johannes; Yavor, Mikhail I.; Geissel, Hans; Scheidenberger, Christoph

2017-06-01

A novel method for (ultra-)high-resolution spatial mass separation in time-of-flight mass spectrometers is presented. Ions are injected into a time-of-flight analyzer from a radio frequency (rf) trap, dispersed in time-of-flight according to their mass-to-charge ratios and then re-trapped dynamically in the same rf trap. This re-trapping technique is highly mass-selective and after sufficiently long flight times can provide even isobaric separation. A theoretical treatment of the method is presented and the conditions for optimum performance of the method are derived. The method has been implemented in a multiple-reflection time-of-flight mass spectrometer and mass separation powers (FWHM) in excess of 70,000, and re-trapping efficiencies of up to 35% have been obtained for the protonated molecular ion of caffeine. The isobars glutamine and lysine (relative mass difference of 1/4000) have been separated after a flight time of 0.2 ms only. Higher mass separation powers can be achieved using longer flight times. The method will have important applications, including isobar separation in nuclear physics and (ultra-)high-resolution precursor ion selection in multiple-stage tandem mass spectrometry. [Figure not available: see fulltext.

Quantification, confirmation and screening capability of UHPLC coupled to triple quadrupole and hybrid quadrupole time-of-flight mass spectrometry in pesticide residue analysis.

Science.gov (United States)

Grimalt, Susana; Sancho, Juan V; Pozo, Oscar J; Hernández, Félix

2010-04-01

The potential of three mass spectrometry (MS) analyzers (triple quadrupole, QqQ; time of flight, TOF; and quadrupole time of flight, QTOF) has been investigated and compared for quantification, confirmation and screening purposes in pesticide residue analysis of fruit and vegetable samples. For this purpose, analytical methodology for multiresidue determination of 11 pesticides, taken as a model, has been developed and validated in nine food matrices for the three mass analyzers coupled to ultra high pressure liquid chromatography. In all cases, limits of quantification around 0.01 mg/kg were reached, fulfilling the most restrictive case of baby-food analysis. Regarding absolute sensitivity, the lower limits of detection were obtained, as expected, for QqQ (100 fg), whereas slightly higher limits (300 fg) were obtained for both TOF and QTOF. Confirmative capacity of each analyzer was studied for each analyte based on the identification points (IPs) criterion, useful for a comprehensive comparison. QTOF mass analyzer showed the highest confirmatory capacity, although QqQ normally led to sufficient number of IPs, even at lower concentration levels. The potential of TOF MS was also investigated for screening purposes. To this aim, around 50 commercial fruits and vegetables samples were analyzed, searching for more than 400 pesticides. TOF MS proved to be an attractive analytical tool for rapid detection and reliable identification of a large number of pesticides thanks to the full spectrum acquisition at accurate mass with satisfactory sensitivity. This process is readily boosted when combined with specialized software packages, together with theoretical exact mass databases. Several pesticides (e.g. carbendazim in citrus and indoxacarb in grape) were detected in the samples. Further unequivocal confirmation of the identity was performed using reference standards and/or QTOF MS/MS experiments. Copyright 2010 John Wiley & Sons, Ltd.

Quadrupole Ion Traps

Indian Academy of Sciences (India)

to do precision spectroscopic measurements on these ions. ... Bonn, investigated the non-magnetic quadrupole mass filter, .... the details of which will be discussed in the subse- ... the radial plane the ion undergoes a circular motion with the.

Electronics for processing of data from a double collector isotopic ratio mass spectrometer

International Nuclear Information System (INIS)

Handu, V.K.

1979-01-01

The output data available from the mass spectrometer type MS-660 developed in the mass spectrometry section of Technical Physics Division of the Bhabha Atomic Research Centre, Bombay, for the determination of H/D ratios in liquid/gas sample consist of uncompensated mass 3 and mass 2 signals. After the mass 3 signal has been compensated for H 3 + formation, the on-line ratio of compensated mass 3 to mass 2 is calculated, displayed, and then printed on a printer for record. The electronic compensation circuit, the discrete voltage-to-frequency (V/F) converter circuit, the ratio calculating system using V/F converters, and a digital interface system for Hindustan Teleprinter to print out the ratios are explained. Results obtained on mass spectrometer MS-660 are presented. (auth.)

Cherenkov detectors and a new effective-mass spectrometer method

Czech Academy of Sciences Publication Activity Database

Hladký, Jan

2006-01-01

Roč. 75, - (2006), s. 854-855 ISSN 0969-806X Institutional research plan: CEZ:AV0Z10100502 Keywords : Cherenkov radiation * spectrometer * effective mass method Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 0.868, year: 2006

The AMS [Accelerator Mass Spectrometer] program at LLNL

International Nuclear Information System (INIS)

Proctor, I.D.

1988-09-01

Livermore will have an operational Accelerator Mass Spectrometer (AMS) by mid-1989 as part of its new Multi-user Tandem Laboratory. The spectrometer was designed primarily for applications in archaeology and the geosciences and was co-funded by the University of California Regents. Radiological control for personnel protection, ion sources and injection systems, the tandem and all beam handling hardware are operated with a distributed processor computer control system. The Tandem is the former University of Washington injector FN which has been upgraded with Dowlish tubes, pelletron charging and SF 6 gas. Design goals for the AMS system, computer aided operation, automated measurement capability, initial results and some of our intended applications will be presented. 5 refs., 2 figs

All systems go for LHC quadrupoles

CERN Multimedia

2003-01-01

The series fabrication of the Main Quadrupole cold masses for the LHC has begun with the delivery of the first unit on February 12th. The superconducting dipole magnets required to bend the proton beams around the LHC are often in the news. Less famous, perhaps, but equally important are the 360 main quadrupole (MQ) magnets, which will perform the principal focusing around the 27 km ring. CERN and CEA-Saclay began collaborating on the development and prototyping of these magnets in 1989. This resulted in five highly successful quadrupole units - also known as short straight sections - one of which was integrated for testing in String 1, and two others of the final design in String 2. Once the tests had confirmed the validity of the design and realization, the fabrication of the 360 cold masses had to be transferred to industry. After highly competitive tendering, the German firm ACCEL Instruments was entrusted both with the construction of the quadrupole magnets themselves, and with their assembly into the co...

Wide-Scope Screening Method for Multiclass Veterinary Drug Residues in Fish, Shrimp, and Eel Using Liquid Chromatography-Quadrupole High-Resolution Mass Spectrometry.

Science.gov (United States)

Turnipseed, Sherri B; Storey, Joseph M; Lohne, Jack J; Andersen, Wendy C; Burger, Robert; Johnson, Aaron S; Madson, Mark R

2017-08-30

A screening method for veterinary drug residues in fish, shrimp, and eel using LC with a high-resolution MS instrument has been developed and validated. The method was optimized for over 70 test compounds representing a variety of veterinary drug classes. Tissues were extracted by vortex mixing with acetonitrile acidified with 2% acetic acid and 0.2% p-toluenesulfonic acid. A centrifuged portion of the extract was passed through a novel solid phase extraction cartridge designed to remove interfering matrix components from tissue extracts. The eluent was then evaporated and reconstituted for analysis. Data were collected with a quadrupole-Orbitrap high-resolution mass spectrometer using both nontargeted and targeted acquisition methods. Residues were detected on the basis of the exact mass of the precursor and a product ion along with isotope pattern and retention time matching. Semiquantitative data analysis compared MS 1 signal to a one-point extracted matrix standard at a target testing level. The test compounds were detected and identified in salmon, tilapia, catfish, shrimp, and eel extracts fortified at the target testing levels. Fish dosed with selected analytes and aquaculture samples previously found to contain residues were also analyzed. The screening method can be expanded to monitor for an additional >260 veterinary drugs on the basis of exact mass measurements and retention times.

Simultaneous determination of iridoid glycosides, phenethylalcohol glycosides and furfural derivatives in Rehmanniae Radix by high performance liquid chromatography coupled with triple-quadrupole mass spectrometry

DEFF Research Database (Denmark)

Xu, Jun; Wu, Jie; Zhu, Ling-Ying

2012-01-01

In this study, a sensitive and selective method for simultaneously quantifying eight major components (four iridoid glycosides, three phenethylalcohol glycosides and one furfural derivative) of Rehmanniae Radix by high performance liquid chromatography coupled with triple-quadrupole mass spectrom......In this study, a sensitive and selective method for simultaneously quantifying eight major components (four iridoid glycosides, three phenethylalcohol glycosides and one furfural derivative) of Rehmanniae Radix by high performance liquid chromatography coupled with triple-quadrupole mass...

Analysis of Nitro-aromatic and Nitramine Explosives by Atmospheric Pressure Chemical Ionization / High Performance Liquid Chromatography / Mass Spectrometry / Mass Spectrometry

International Nuclear Information System (INIS)

Hicks, B.J.; Han, W.; Robben, J.R.

2009-01-01

This procedure is capable of separating and quantifying twenty-nine high explosives and internal surrogates with a single injection. After the initial preparation step, the sample is introduced to the high performance liquid chromatograph for target separation, ionized by atmospheric pressure chemical ionization and the explosives of interest are isolated / quantified by mass spectrometry / mass spectrometry. Concentrations of the target explosives are measured relative to the response of both internal and external standard concentrations. A C-18 reverse phase high performance liquid chromatograph column is used for separation. Ionization is performed using both positive and negative atmospheric pressure chemical ionization resulting in a molecular ion with little fragmentation. These ions are isolated at the first quadrupole of the mass spectrometer, dissociated by collision with argon in the collision cell and the resulting daughter ions are isolated at the second quadrupole. These daughter ions then reach the detector where they are quantified. To date this procedure represents the most thorough high performance liquid chromatography / mass spectrometry / mass spectrometry explosives analysis available in the environmental chemistry market. (authors)

Equipment and performance of the Q3D spectrometer installed at the tandem laboratory of Saclay

International Nuclear Information System (INIS)

Berthier, B.

1979-01-01

A quadrupole - dipole - dipole - dipole (Q3D) magnetic spectrometer with proportional gas counter which has been installed at the tandem laboratory of Saclay is described. Typical results are given indicating the performance of the apparatus in studies of heavy ion reactions at tandem energies for which good energy resolution and large solid angles are required. Improvements to allow the detection of heavier masses and less energetic ions with better energy resolution are planned. (U.K.)

The Varian MAT-250 mass spectrometer. Steady isotopes laboratory

International Nuclear Information System (INIS)

Hernandez M, V.; Tavera D, M.L.

1997-01-01

This work treats over the performance and applications of the Varian Mat-250 mass spectrometer which is in the environmental isotope laboratory. It can be applied over topics such as: ions formation, acceleration and collimation, ions separation, ions detection, data transformation, sampling, δ notation. (Author)

Magnetic and electric deflector spectrometers for ion emission analysis from laser generated plasma

Directory of Open Access Journals (Sweden)

Torrisi Lorenzo

2018-01-01

Full Text Available The pulsed laser-generated plasma in vacuum and at low and high intensities can be characterized using different physical diagnostics. The charge particles emission can be characterized using magnetic, electric and magnet-electrical spectrometers. Such on-line techniques are often based on time-of-flight (TOF measurements. A 90° electric deflection system is employed as ion energy analyzer (IEA acting as a filter of the mass-to-charge ratio of emitted ions towards a secondary electron multiplier. It determines the ion energy and charge state distributions. The measure of the ion and electron currents as a function of the mass-to-charge ratio can be also determined by a magnetic deflector spectrometer, using a magnetic field of the order of 0.35 T, orthogonal to the ion incident direction, and an array of little ion collectors (IC at different angles. A Thomson parabola spectrometer, employing gaf-chromix as detector, permits to be employed for ion mass, energy and charge state recognition. Mass quadrupole spectrometry, based on radiofrequency electric field oscillations, can be employed to characterize the plasma ion emission. Measurements performed on plasma produced by different lasers, irradiation conditions and targets are presented and discussed. Complementary measurements, based on mass and optical spectroscopy, semiconductor detectors, fast CCD camera and Langmuir probes are also employed for the full plasma characterization. Simulation programs, such as SRIM, SREM, and COMSOL are employed for the charge particle recognition.

Magnetic and electric deflector spectrometers for ion emission analysis from laser generated plasma

Science.gov (United States)

Torrisi, Lorenzo; Costa, Giuseppe; Ceccio, Giovanni; Cannavò, Antonino; Restuccia, Nancy; Cutroneo, Mariapompea

2018-01-01

The pulsed laser-generated plasma in vacuum and at low and high intensities can be characterized using different physical diagnostics. The charge particles emission can be characterized using magnetic, electric and magnet-electrical spectrometers. Such on-line techniques are often based on time-of-flight (TOF) measurements. A 90° electric deflection system is employed as ion energy analyzer (IEA) acting as a filter of the mass-to-charge ratio of emitted ions towards a secondary electron multiplier. It determines the ion energy and charge state distributions. The measure of the ion and electron currents as a function of the mass-to-charge ratio can be also determined by a magnetic deflector spectrometer, using a magnetic field of the order of 0.35 T, orthogonal to the ion incident direction, and an array of little ion collectors (IC) at different angles. A Thomson parabola spectrometer, employing gaf-chromix as detector, permits to be employed for ion mass, energy and charge state recognition. Mass quadrupole spectrometry, based on radiofrequency electric field oscillations, can be employed to characterize the plasma ion emission. Measurements performed on plasma produced by different lasers, irradiation conditions and targets are presented and discussed. Complementary measurements, based on mass and optical spectroscopy, semiconductor detectors, fast CCD camera and Langmuir probes are also employed for the full plasma characterization. Simulation programs, such as SRIM, SREM, and COMSOL are employed for the charge particle recognition.

Nuclear quadrupole resonance spectrometer for chlorine compounds

International Nuclear Information System (INIS)

Lasanda, J.

1976-01-01

An NQR spectrometer is described based on a superregenerative oscillator for high sensitivity. The application of a Pound-Knight type oscillator using field effect transistors resulted in higher stability of oscillation amplitude in the desired range of 10 to 50 MHz. The use of a current source allowed to set good signal-to-noise ratio independently of the amplitude of oscillations. For synchronizing of both oscillators a balanced modulator was used. (author)

The development of a completely automated oxygen isotope mass spectrometer

International Nuclear Information System (INIS)

Ahern, T.K.

1980-01-01

A completely automated mass spectrometer system has been developed to measure the oxygen isotope ratio of carbon dioxide samples. The system has an accuracy of 0.03 percent, and is capable of analyzing more than 100 samples a day. The system uses an Interdata minicomputer as the primary controller. The intelligence of the system is contained within hardware circuits, software within the minicomputer, and firmware written for a Motorola 6802 microprocessor. A microprocessor-based inlet system controller maximizes the throughput of carbon dioxide samples within the inlet system. The inlet system normally contains four different aliquots of carbon dioxide and introduces these samples to the mass spectrometer through a single admittance leak. The system has been used in the analysis of 111 samples of ice taken from the Steele glacier

A generic approach for expanding homolog-targeted residue screening of sulfonamides using a fast matrix separation and class-specific fragmentation-dependent acquisition with a hybrid quadrupole-linear ion trap mass spectrometer

International Nuclear Information System (INIS)

Huang Chunlin; Guo Bin; Wang Xiaoying; Li Jie; Zhu Weitao; Chen Bo; Ouyang Shan; Yao Shouzhuo

2012-01-01

Highlights: ► Generic homolog-targeted screening approach for multi-residual sulfonamide analogs. ► Single-tube extraction/partitioning-multifunction adsorption cleanup for direct injection. ► Class-specific fragmentation for expanding coverage of N 4 -acetyl and N-OH metabolites. ► PreS–IDA–EPI in LC–QqLIT for simultaneous screening and confirmation of real samples. - Abstract: A generic and efficient homolog-targeted approach was used to expand screening and detection of target class of sulfonamides and structural analogs, based on a fast single-tube extraction/partitioning-multifunction adsorption cleanup (SEP/MAC) for class-specific fragmentation-dependent acquisition with a liquid chromatography–hybrid triple-quadrupole linear ion trap mass spectrometer (LC–QqLIT). By combining the two-stage process conducted in a single tube as one-pot protocol, the straightforward SEP/MAC procedure was optimized to offer clean extracts with reasonable recovery (71–109% with RSDs 4 -acetyl and hydroxylamine metabolites plus their possible dimers. Moreover, the PreS-triggered automatically enhanced product ion spectral acquisition enabled simultaneous screening, profiling and confirmation of an unlimited number of analytes belonging to the sulfonamide class within a single analysis. The validation and application results of the generic SEP/MAC-based LC–QqLIT strategy consistently demonstrated favorable performances with acceptable accuracy (67–116%), precision (RSDs −1 ) to meet the acceptance criteria for all the sulfonamide–tissue combinations. Thus, the integration of the matrix-independent SEP/MAC procedure and the multiparameter matching algorithm with the unit-resolution LC–QqLIT instrument can serve as a valuable semi-targeted discovery strategy for rapid screening and reliable quantitative/confirmatory analysis of real samples.

Injection system of the minicyclotron accelerator mass spectrometer

International Nuclear Information System (INIS)

Liu Yonghao; Li Deming; Chen Maobai; Lu Xiangshun

1999-01-01

The existing injection system of the SMCAMS (super-sensitive mini-cyclotron accelerator mass spectrometer) is described together with the discussion of its disadvantages exposed after having been operating for five years, which provides a basis for consideration of improvements to the injection system. An optimized injection system with an analytical magnet added prior to the minicyclotron has been proposed and calculated

Laboratory investigation of photochemical oxidation of organic aerosol from wood fires 2: analysis of aerosol mass spectrometer data

Directory of Open Access Journals (Sweden)

A. P. Grieshop

2009-03-01

Full Text Available Experiments were conducted to investigate the effects of photo-oxidation on organic aerosol (OA in dilute wood smoke by exposing emissions from soft- and hard-wood fires to UV light in a smog chamber. This paper focuses on changes in OA composition measured using a unit-mass-resolution quadrupole Aerosol Mass Spectrometer (AMS. The results highlight how photochemical processing can lead to considerable evolution of the mass, volatility and level of oxygenation of biomass-burning OA. Photochemical oxidation produced substantial new OA, more than doubling the OA mass after a few hours of aging under typical summertime conditions. Aging also decreased the volatility of the OA and made it progressively more oxygenated. The results also illustrate strengths of, and challenges with, using AMS data for source apportionment analysis. For example, the mass spectra of fresh and aged BBOA are distinct from fresh motor-vehicle emissions. The mass spectra of the secondary OA produced from aging wood smoke are very similar to those of the oxygenated OA (OOA that dominates ambient AMS datasets, further reinforcing the connection between OOA and OA formed from photo-chemistry. In addition, aged wood smoke spectra are similar to those from OA created by photo-oxidizing dilute diesel exhaust. This demonstrates that the OOA observed in the atmosphere can be produced by photochemical aging of dilute emissions from different types of combustion systems operating on fuels with modern or fossil carbon. Since OOA is frequently the dominant component of ambient OA, the similarity of spectra of aged emissions from different sources represents an important challenge for AMS-based source apportionment studies.

A reflecting time-of-flight mass spectrometer

Energy Technology Data Exchange (ETDEWEB)

Tang, X

1991-01-01

The design, construction and operation of a reflecting time-of-flight mass spectrometer and the details of the ion mirror are discussed. The principle of velocity focusing with a single-stage ion mirror and the effect of the acceleration region are discussed. The performance of the reflecting instrument is described. Its detection limit is illustrated by observation of [M + H][sup +] ions from [approximately]5-35 femtomoles of various peptides. The factors that affect the resolution are discussed. The principle and operation of the reflecting instrument as a tandem mass spectrometer is described; this involves correlated detection of neutral and ionized fragments. The efficiency, resolution, sensitivity, and mass determination of daughter ions by this method are discussed. Methods of sample preparation are described. By using a nitrocellulose substrate, organic molecular ions as large as bovine insulin (MW 5733) were detected for the first time with low energy (keV) ion bombardment of a solid surface. Many daughter ion spectra resulting from metastable decay of parent ions have been studied. Secondary ions [(CsI)[sub n]Cs][sup +] with n up to [approximately]50 were detected; all clusters were found to be metastable, with most lifetimes <100 [mu]s, and for n>10 the daughter ions are dominant in the mass spectrum. Peptides of mass up to [approximately]2000 u have been studied with the correlated method; the daughter ion spectra were found to be strongly influenced by the identity of the bound cation (H[sup +], Na[sup +], K[sup +], or Ag[sup +]). Many daughter ions formed by known reactions yield structure and sequence information about the peptides. In addition, the [M + Na][sup +] and [M + Ag][sup +] ions decompose by a previously unreported pathway, namely, rearrangement of a C-terminal carboxyl oxygen onto the daughter ion containing the N-terminus. Both the reflected spectra and daughter ion spectra were found useful in peptide sequencing.

Sources and atmospheric processing of organic aerosol in the Mediterranean: insights from aerosol mass spectrometer factor analysis

Directory of Open Access Journals (Sweden)

L. Hildebrandt

2011-12-01

Full Text Available Atmospheric particles were measured in the late winter (25 February–26 March 2009 at a remote coastal site on the island of Crete, Greece during the Finokalia Aerosol Measurement Experiment-2009. A quadrupole aerosol mass spectrometer (Q-AMS was employed to quantify the size-resolved chemical composition of non-refractory submicron aerosol, and a thermodenuder was used to analyze the organic aerosol (OA volatility. Complementary measurements included particle size distributions from a scanning mobility particle sizer, inorganic and organic particle composition from filter analysis, air ion concentrations, O₃, NO_x and NO_y concentrations, and meteorological measurements. Factor analysis was performed on the OA mass spectra, and the variability in OA composition could best be explained with three OA components. The oxygenated organic aerosol (OOA was similar in composition and volatility to the summertime OA previously measured at this site and may represent an effective endpoint in particle-phase oxidation of organics. The two other OA components, one associated with amines (Amine-OA and the other probably associated with the burning of olive branches (OB-OA, had very low volatility but were less oxygenated. Hydrocarbon-like organic aerosol (HOA was not detected. The absence of OB-OA and Amine-OA in the summer data may be due to lower emissions and/or photochemical conversion of these components to OOA.

Simultaneous analysis by Quadrupole-Orbitrap mass spectrometry and UHPLC-MS/MS for the determination of sedative-hypnotics and sleep inducers in adulterated products.

Science.gov (United States)

Lee, Ji Hyun; Park, Han Na; Choi, Ji Yeon; Kim, Nam Sook; Park, Hyung-Joon; Park, Seong Soo; Baek, Sun Young

2017-12-01

Adulterated products are continuously detected in society and cause problems. In this study, we developed and validated a method for determining synthetic sedative-hypnotics and sleep inducers, including barbital, benzodiazepam, zolpidem, and first-generation antihistamines, in adulterated products using Quadrupole-Orbitrap mass spectrometry and ultrahigh performance liquid chromatography with tandem mass spectrometry. In Quadrupole-Orbitrap mass spectrometry analysis, target compounds were confirmed using a combination of retention time, mass tolerance, mass accuracy, and fragment ions. For quantification, several validation parameters were employed using ultrahigh performance liquid chromatography with tandem mass spectrometry. The limit of detection and limit of quantitation was 0.05-53 and 0.17-177 ng/mL, respectively. The correlation coefficient for linearity was more than 0.995. The intra- and interassay accuracies were 86-110 and 84-111%, respectively. Their precision values were evaluated as within 4.0 (intraday) and 10.7% (interday). Mean recoveries of target compounds in adulterated products ranged from 85 to 116%. The relative standard deviation of stability was less than 10.7% at 4°C for 48 h. The 144 adulterated products obtained over 3 years (2014-2016) from online and in-person vendors were tested using established methods. After rapidly screening with Quadrupole-Orbitrap mass spectrometry, the detected samples were quantified using ultrahigh performance liquid chromatography with tandem mass spectrometry. Two of them were adulterated with phenobarbital. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ion deposition by inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Hu, K.; Houk, R.S.

1996-01-01

An atmospheric pressure inductively coupled plasma (ICP) is used with a quadrupole mass spectrometer (MS) for ion deposition. The deposited element is introduced as a nebulized aqueous solution. Modifications to the ICP-MS device allow generation and deposition of a mass-resolved beam of 165 Ho + at 5x10 12 ions s -1 . The ICP is a universal, multielement ion source that can potentially be used for applications such as deposition of mixtures of widely varying stoichiometry or of alternating layers of different elements. copyright 1996 American Vacuum Society

Design and realization of a space-borne reflectron time of flight mass spectrometer: electronics and measuring head

International Nuclear Information System (INIS)

Devoto, P.

2006-03-01

The purpose of this thesis is the design of the electronics of a time of flight mass spectrometer, the making and the vacuum tests of a prototype which can be put onboard a satellite. A particular effort was necessary to decrease to the maximum the mass and electric consumption of the spectrometer, which led to the development of new circuits. The work completed during this thesis initially concerns the electronics of the measuring equipment which was conceived in a concern for modularity. A complete 'reflectron' type mass spectrometer was then designed, simulated and developed. The built prototype, which uses the developed electronics, was exposed to ion flows of different masses and energies in the CESR vacuum chambers. Its measured performances validate the implemented principles and show that an identical mass spectrometer can be put onboard a satellite with profit, for planetary or solar missions. (author)

Investigation of material systems in industry and research by organic analytical mass spectrometer

International Nuclear Information System (INIS)

Decsy, Z.

1980-01-01

The modern, many-sided and efficient organic analytical mass spectrometer possesses all the structure-and composition-examination possibilities of complex organic analytical laboratories. The article presents the advantages and possibilities of the application of mass spectrometer in different operation modes in connection with the examination of a petrochemical synthesis product: ortho-phenylene-diamine, an experimental gas odorizing material, a petroleum production auxiliary material: petroleum sulfonate, a gasoline sample and a sulfur-containing standard substance. The useful operation modes include spectrum records of low and high resolution, the application of space ionization and space desorption ion sources as well as the ''mass fragmentographic'' measuring method. (author)

Commissioning of the AEI MS702 mass spectrometer

International Nuclear Information System (INIS)

Pearton, D.C.G.; Sobiecki, A.

1978-01-01

The setting-up and commissioning of the AEI MS702 mass spectrometer is described. Its individual components and their use are discussed, as well as the sample preparation, analysis, and reduction of data. A comprehensive list is given of instrumental breakdowns, and the application of the technique to several matrices is outlined. Improvements and modifications to the technique, including the use of a minicomputer, are suggested

Application of gas chromatography-surface ionization organic mass spectrometry to forensic toxicology.

Science.gov (United States)

Ishii, Akira; Watanabe-Suzuki, Kanako; Seno, Hiroshi; Suzuki, Osamu; Katsumata, Yoshinao

2002-08-25

Surface ionization (SI), which consists in the formation of positive and negative ions along the course of thermal desorption of particles from a solid surface, was first applied as a detector for gas chromatography (GC), GC-surface ionization detection (SID); we developed many new sensitive methods for the determination of abused and other drugs by GC-SID. Recently, Fujii has devised a combination of SI and a quadrupole mass spectrometer and named this system a surface ionization organic mass spectrometer (SIOMS), which is highly selective and sensitive for organic compounds containing tertiary amino groups. We have tried to apply this mass spectrometer to forensic toxicological study; so far we have succeeded in determining important drugs-of-abuse and toxic compounds, such as phencyclidine (PCP), pethidine, pentazocine, MPTP and its derivatives from human body fluids with high sensitivity and selectivity. In this review, we describe our recent studies on the application of GC-SIOMS to forensic toxicology. Copyright 2002 Elsevier Science B.V.

Design and construction of a magnetic sector mass spectrometer

International Nuclear Information System (INIS)

Dallaqua, R.S.; Ludwig, G.O.; Montes, A.

1991-08-01

In this work we describe the design and construction of a sector magnetic mass spectrometer. The main parts of the instrument are: ion source, grids (extraction, energy analysis and ion acceleration), electrostatic lens, magnetic sector and detector. All these components are kept inside a vacuum chamber evacuated by a turbomolecular pump. (author)

Collision-induced dissociation with Fourier transform mass spectrometry

International Nuclear Information System (INIS)

Cody, R.B.; Burnier, R.C.; Freiser, B.S.

1982-01-01

Collision-induced dissociations (CID) is demonstrated on a number of primary and secondary ions using a Nicolet prototype Fourier transform mass spectrometer (FT-MS). Like the triple quadrupole technique, CID using FT-MS is a relatively low energy and efficient process. The ability to study a wide range of ion-molecule reaction products is exemplified by results on proton-bound dimers and transition metal containing ionic species. Variation of collision energy by varying the RF irradiation level can provide information about product distributions as a function of energy as well as yield ion structural information. Like the triple quadrupole technique, no slits are employed and virtually all of the fragment ions formed by the CID process may be detected. Unlike all previous mass spectrometric techniques for studying CID, a tandem instrument is not required, and different experiments are performed by making software modifications rather than hardware modifications

A Dual Source Ion Trap Mass Spectrometer for the Mars Organic Molecule Analyzer of ExoMars 2018

Science.gov (United States)

Brickerhoff, William B.; vanAmerom, F. H. W.; Danell, R. M.; Arevalo, R.; Atanassova, M.; Hovmand, L.; Mahaffy, P. R.; Cotter, R. J.

2011-01-01

We present details on the objectives, requirements, design and operational approach of the core mass spectrometer of the Mars Organic Molecule Analyzer (MOMA) investigation on the 2018 ExoMars mission. The MOMA mass spectrometer enables the investigation to fulfill its objective of analyzing the chemical composition of organic compounds in solid samples obtained from the near surface of Mars. Two methods of ionization are realized, associated with different modes of MOMA operation, in a single compact ion trap mass spectrometer. The stringent mass and power constraints of the mission have led to features such as low voltage and low frequency RF operation [1] and pulse counting detection.

Characterization of peptide-oligonucleotide heteroconjugates by mass spectrometry.

OpenAIRE

Jensen, O N; Kulkarni, S; Aldrich, J V; Barofsky, D F

1996-01-01

Two peptide-oligothymidylic acids, prepared by joining an 11 residue synthetic peptide containing one internal carboxyl group (Asp side chain) to amino-linker-5'pdT6 and amino-linker-5'pdT10 oligonucleotides, were analyzed by matrix-assisted laser desorption/ionization (MALDI) on a linear time-of-flight mass spectrometer and by electrospray ionization (ESI) on a triple-quadrupole system. These synthetic compounds model peptide-nucleic acid heteroconjugates encountered in antisense research an...

Calibration of a Noble Gas Mass Spectrometer with an Atmospheric Argon Standard (Invited)

Science.gov (United States)

Prasad, V.; Grove, M.

2009-12-01

Like other mass spectrometers, gas source instruments are very good at precisely measuring isotopic ratios but need to be calibrated with a standard to be accurate. The need for calibration arises due to the complicated ionization process which inefficiently and differentially creates ions from the various isotopes that make up the elemental gas. Calibration of the ionization process requires materials with well understood isotopic compositions as standards. Our project goal was to calibrate a noble gas (Noblesse) mass spectrometer with a purified air sample. Our sample obtained from Ocean Beach in San Francisco was under known temperature, pressure, volume, humidity. We corrected the pressure for humidity and used the ideal gas law to calculate the number of moles of argon gas. We then removed all active gasses using specialized equipment designed for this purpose at the United States Geological Survey. At the same time, we measured the volume ratios of various parts of the gas extraction line system associated with the Noblesse mass spectrometer. Using this data, we calculated how much Ar was transferred to the reservoir from the vacuum-sealed vial that contained the purified gas standard. Using similar measurements, we also calculated how much Ar was introduced into the extraction line from a pipette system and how much of this Ar was ultimately expanded into the Noblesse mass spectrometer. Based upon this information, it was possible to calibrate the argon sensitivity of the mass spectrometer. From a knowledge of the isotopic composition of air, it was also possible to characterize how ionized argon isotopes were fractionated during analysis. By repeatedly analyzing our standard we measured a 40Ar Sensitivity of 2.05 amps/bar and a 40Ar/36Ar ratio of 309.2 on the Faraday detector. In contrast, measurements carried out by ion counting using electron multipliers yield a value (296.8) which is much closer to the actual atmospheric 40Ar/36Ar value of 295.5.

Frequency-scanning MALDI linear ion trap mass spectrometer for large biomolecular ion detection.

Science.gov (United States)

Lu, I-Chung; Lin, Jung Lee; Lai, Szu-Hsueh; Chen, Chung-Hsuan

2011-11-01

This study presents the first report on the development of a matrix-assisted laser desorption ionization (MALDI) linear ion trap mass spectrometer for large biomolecular ion detection by frequency scan. We designed, installed, and tested this radio frequency (RF) scan linear ion trap mass spectrometer and its associated electronics to dramatically extend the mass region to be detected. The RF circuit can be adjusted from 300 to 10 kHz with a set of operation amplifiers. To trap the ions produced by MALDI, a high pressure of helium buffer gas was employed to quench extra kinetic energy of the heavy ions produced by MALDI. The successful detection of the singly charged secretory immunoglobulin A ions indicates that the detectable mass-to-charge ratio (m/z) of this system can reach ~385 000 or beyond.

Mass spectrometer data system at LLL

International Nuclear Information System (INIS)

Friesen, R.D.

1975-01-01

The data systems on the three mass spectrometers at LLL are computer-controlled, pulse-counting systems synchronized to a repeatedly-swept magnetic field. The data are accumulated in the memory of the computer or in a Nuclear Data ND 180 in a multi-scaler mode of operation. This mode of sweeping allows a continuous check of the background stability and makes tune-up easier. But the main benefit is a reduction in the required ion emission rate stability. By the use of standards to set the system dead time, we have been able to utilize the sensitivity of a pulse counting system without the expense of exotic equipment

The analysis of uranium in environmental sample by mass spectrometer combined with isotopic dilution

International Nuclear Information System (INIS)

Fu Zhonghua; Jia Baoting; Han Jun

2003-01-01

Uranium in the environmental sample was analyzed by mass spectrometer combined with isotopic dilution. Before mass spectrometer analysis, samples were dissolved in a concentrated acidic solution containing HNO 3 , HF and HClO 4 and chemically processed to suit the analysis requirement. Analysis results indicated that the uranium content was 0.08 μg/g in river water, 0.1 μg/g in evergreen foliage, and 5-11 μg/g in surface soil respectively. (authors)

Mass measurement of halo nuclides and beam cooling with the mass spectrometer Mistral

International Nuclear Information System (INIS)

Bachelet, C.

2004-12-01

Halo nuclides are a spectacular drip-line phenomenon and their description pushes nuclear theories to their limits. The most critical input parameter is the nuclear binding energy; a quantity that requires excellent measurement precision, since the two-neutron separation energy is small at the drip-line by definition. Moreover halo nuclides are typically very short-lived. Thus, a high accuracy instrument using a quick method of measurement is necessary. MISTRAL is such an instrument; it is a radiofrequency transmission mass spectrometer located at ISOLDE/CERN. In July 2003 we measured the mass of the Li 11 , a two-neutron halo nuclide. Our measurement improves the precision by a factor 6, with an error of 5 keV. Moreover the measurement gives a two-neutron separation energy 20% higher than the previous value. This measurement has an impact on the radius of the nucleus, and on the state of the two valence neutrons. At the same time, a measurement of the Be 11 was performed with an uncertainty of 4 keV, in excellent agreement with previous measurements. In order to measure the mass of the two-neutron halo nuclide Be 14 , an ion beam cooling system is presently under development which will increase the sensitivity of the spectrometer. The second part of this work presents the development of this beam cooler using a gas-filled Paul trap. (author)

Large acceptance spectrometers for invariant mass spectroscopy of exotic nuclei and future developments

Energy Technology Data Exchange (ETDEWEB)

Nakamura, T.; Kondo, Y.

2016-06-01

Large acceptance spectrometers at in-flight RI separators have played significant roles in investigating the structure of exotic nuclei. Such spectrometers are in particular useful for probing unbound states of exotic nuclei, using invariant mass spectroscopy with reactions at intermediate and high energies. We discuss here the key characteristic features of such spectrometers, by introducing the recently commissioned SAMURAI facility at the RIBF, RIKEN. We also investigate the issue of cross talk in the detection of multiple neutrons, which has become crucial for exploring further unbound states and nuclei beyond the neutron drip line. Finally we discuss future perspectives for large acceptance spectrometers at the new-generation RI-beam facilities.

Mass spectrometric studies of bimolecular reactions in a selected ion flow tube (SIFT)

International Nuclear Information System (INIS)

Shul, R.J.; Upschulte, B.L.; Passarella, R.; Keesee, R.G.; Castleman, A.W.

1985-01-01

The rate coefficients for a number of thermal energy charge transfer reactions have been obtained with a selected ion flow tube (SIFT). The reactions studied involve Ar + and Ar 2 + with a variety of neutral molecules including: O 2 , CS 2 , CO 2 , SO 2 , H 2 S, NH 3 , and SF 6 . Such reactions have been of long-standing interest in the field of gas-phase ion-molecule chemistry from both a practical and fundamental point of view. Consideration of charge transfer reactions as possible sources of chemical lasers and their role in ionospheric and interstellar chemistry account for much of the interest. Fundamentally, the mechanism involved in these reactions has yet to be definitively established. The consumption deposition of energy into internal modes and translational degrees of freedom in such reactions has also been a topic of considerable debate. The apparatus consists of five main components: an ion source, SIFT quadrupole, ion injector, flow tube, and a mass spectrometer detection system. Ions formed in a high pressure source leak into a SIFT quadrupole where they are mass selected. The primary ion of interest is then injected into the flow tube where reactions are studied. Once in the flow tube the ions are carried downstream by an inert buffer gas, either argon, nitrogen, or helium in the present study. Neutral reactant gas is added through a reactant gas inlet (RGI) at an appropriate location downstream in the flow tube, and allowed to react with the injected ions. Ions on the flow tube axis are sampled through a 1 mm orifice where they are mass analyzed by a second quadrupole mass spectrometer and detected with a channeltron electron multiplier

A new time of flight mass spectrometer for absolute dissociative electron attachment cross-section measurements in gas phase

Science.gov (United States)

Chakraborty, Dipayan; Nag, Pamir; Nandi, Dhananjay

2018-02-01

A new time of flight mass spectrometer (TOFMS) has been developed to study the absolute dissociative electron attachment (DEA) cross section using a relative flow technique of a wide variety of molecules in gas phase, ranging from simple diatomic to complex biomolecules. Unlike the Wiley-McLaren type TOFMS, here the total ion collection condition has been achieved without compromising the mass resolution by introducing a field free drift region after the lensing arrangement. The field free interaction region is provided for low energy electron molecule collision studies. The spectrometer can be used to study a wide range of masses (H- ion to few hundreds atomic mass unit). The mass resolution capability of the spectrometer has been checked experimentally by measuring the mass spectra of fragment anions arising from DEA to methanol. Overall performance of the spectrometer has been tested by measuring the absolute DEA cross section of the ground state SO2 molecule, and the results are satisfactory.

Analysis of phosphatidylcholine oxidation products in human plasma using quadrupole time-of flight mass spectrometry

OpenAIRE

Adachi, Junko; Asano, Migiwa; Yoshioka, Naoki; Nushida, Hideyuki; Ueno, Yasuhiro

2006-01-01

We report here an application of the previous method for the analysis ofphosphatidylcholine (PC) and lysophosphatidylcholine (lysoPC) oxidation products inhuman plasma using quadrupole time of flight (Q-TOF) mass spectrometry withelectrospray ionization. We separated these products using an HPLC C8 column witha gradient of methanol and 10 mM aqueous ammonium acetate. Monohydroperoxides,epoxyhydroxy derivatives, oxo derivatives, and trihydroxides of palmitoyl-linoleoyl(C16:0/C18:2) PC and stea...

Complete Analysis of a Biologically Active Tetrapeptide: A Project Utilizing Thin-Layer Chromatography and Tandem Quadrupole Mass Spectrometry

Science.gov (United States)

Lefevre, Joseph W.; Dodsworth, David W.

2000-04-01

The biologically active tetrapeptide d-Ala-Gly-l-Phe-d-Leu ([des-Tyr1-d-Ala2-d-Leu5]enkephalin) was analyzed for its amino acid content and stereochemistry by normal and reversed-phase thin-layer chromatography (TLC), and its sequence was determined by tandem quadrupole mass spectrometry. The project involved sequential N-dansylation of a portion of the tetrapeptide, hydrolysis, isolation, and identification of the N-terminal amino acid as dansyl-alanine by comparison with standards using normal-phase TLC. A second portion of the tetrapeptide was hydrolyzed and the resulting four free amino acids were converted to their corresponding dansyl derivatives and purified by preparative normal-phase TLC. The three dansyl amino acids not identified previously were identified by TLC. The stereochemistry of each was determined by comparison with dansyl-dl-amino acid standards using reversed-phase TLC in the presence of ß-cyclodextrin, a chiral mobile phase additive. Finally, the correct amino acid sequence was determined by tandem quadrupole mass spectrometry. This project gives students valuable experience in microscale synthesis, both normal and reversed-phase TLC, stereochemical analysis, and mass spectrometry.

Development of a dedicated isotope mass spectrometer for the noninvasive diagnostics of humans infected with Helicobacter Pylori

Science.gov (United States)

Blashenkov, N. M.; Sheshenya, E. S.; Solov'ev, S. M.; Gall', L. N.; Sachenko, V. M.; Zarutskii, I. V.; Gall', N. R.

2013-06-01

A dedicated isotope mass spectrometer for the noninvasive diagnostics of humans infected with Helicobacter Pylori using the isotope respiratory test is developed. A low-aberration mass analyzer is calculated, an input system that makes it possible to eliminate the memory effects is developed, and a small-size ion detector is constructed. The mass spectrometer is created, and the tests are performed. The measurement accuracy of the 13C/12C and 16O/18O isotope ratios are 1.7 and 2.2‰, respectively. Preliminary medical tests show that the spectrometer can be employed for the desired diagnostics.

Gas chromatographic quadrupole time-of-flight full scan high resolution mass spectrometric screening of human urine in antidoping analysis

NARCIS (Netherlands)

Abushareeda, Wadha; Lyris, Emmanouil; Kraiem, Suhail; Wahaibi, Aisha Al; Alyazidi, Sameera; Dbes, Najib; Lommen, Arjen; Nielen, Michel; Horvatovich, Peter L.; Alsayrafi, Mohammed; Georgakopoulos, Costas

2017-01-01

This paper presents the development and validation of a high-resolution full scan (FS) electron impact ionization (EI) gas chromatography coupled to quadrupole Time-of-Flight mass spectrometry (GC/QTOF) platform for screening anabolic androgenic steroids (AAS) in human urine samples. The World

Precision measurements with the multi-reflection time-of-flight mass spectrometer of ISOLTRAP at ISOLDE/CERN

Energy Technology Data Exchange (ETDEWEB)

Atanasov, Dinko; Ascher, Pauline; Borgmann, Christopher; Boehm, Christine; Eliseev, Sergey; Eronen, Tommi; George, Sebastian; Kisler, Dmitry; Naimi, Sarah [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Beck, Dietrich; Herfurth, Frank; Litvinov, Yuri; Minaya Ramirez, Enrique; Neidherr, Dennis [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Planckstr. 1, 64291 Darmstadt (Germany); Breitenfeldt, Martin [Instituut voor Kern- en Stralingsfysica, Celestijnenlaan 200d - bus 2418, 3001 Heverlee (Belgium); Cakirli, Burcu [University of Istanbul, Department of Physics, 34134 Istanbul (Turkey); Cocolios, Thomas Elias [University of Manchester, Manchester (United Kingdom); Herlert, Alexander Josef [FAIR GmbH, Planckstr. 1, D-64291 Darmstadt (Germany); Kowalska, Magdalena [CERN, Geneva 23, 1211 Geneva (Switzerland); Kreim, Susanne [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); CERN, Geneva 23, 1211 Geneva (Switzerland); Lunney, David; Manea, Vladimir [CSNSM-IN2P3-CNRS, 91405 Orsay Campus, Bat. 104, 108 (France); Rosenbusch, Marco; Schweikhard, Lutz; Wienholtz, Frank; Wolf, Robert [Ernst-Moritz-Arndt-Universitaet, Institut fuer Physik, Felix-Hausdorff-Str. 6, 17487 Greifswald (Germany); Stanja, Juliane; Zuber, Kai [Institut fuer Kern- und Teilchenphysik, Technische Universitaet Dresden, Zellescher Weg 19, 01069 Dresden (Germany)

2014-07-01

The masses of exotic nuclides are among the most important input parameters for modern nuclear theory and astrophysical models. At the high-precision Penning-trap mass spectrometer ISOLTRAP at ISOLDE/CERN, a multi-reflection time-of-flight mass spectrometer (MR-ToF-MS) in combination with a Bradbury-Nielsen gate (BNG) can be used to achieve high-resolution isobar purification with mass-resolving powers of 105 in a few tens of milliseconds. Furthermore, the MR-ToF device can be used as a spectrometer to determine the masses of nuclides with very low yields and short half-lives, where a Penning-trap mass measurement becomes impractical due to the lower transport efficiency and decay losses during the purification and measurement cycles. Recent cross-check experiments show that the MR-ToF MS allows mass measurements with uncertainties in the sub-ppm range. In a first application the mass measurements of the nuclides 53,54Ca was performed, delivered with production rates as low as 10/s and half-lives of only 90(6) ms. The nuclides serve as important benchmarks for testing modern chiral effective theory with realistic 3-body forces. The contribution presents the on-line mass spectrometer ISOLTRAP focusing on the new applications, which became possible after the implementation of the MR-ToF MS into the current setup. In particular, the mass measurements of the neutron-rich calcium isotopes up to A=54 are discussed. In addition, measurements of the isotonic potassium isotopes are reported.

Determination of thyroid hormones in mouse tissues by isotope-dilution microflow liquid chromatography-mass spectrometry method

DEFF Research Database (Denmark)

De Angelis, Meri; Giesert, Florian; Finan, Brian

2016-01-01

). The nano-UPLC system was interfaced with a quadrupole time-of-flight mass spectrometer (Q-TOF2-MS) using the positive ion mode electrospray ionization. In our analytical method the instrumental calibration curves were constructed from 0 to 100pgμL(-1) and all of them showed good linearity (r(2)>0.99...

Inorganic trace analysis by laser ionization mass spectrometry

International Nuclear Information System (INIS)

Becker, S.; Dietze, H.J.

1991-01-01

Among the different spectrometric techniques for trace analysis Laser Ionization Mass Spectrometry (LIMS) is well established as a trace analytic method with a wide coverage. In the LIMS the sample material is evaporated and ionized by means of a focused pulsed laser beam in a laser microplasma, which is formed in the spot area of the irradiated sample. All chemical elements in the sample materials are evaporated and ionized in the laser plasma. The formed ions are separated according to mass and energy by a time-of-flight, quadrupole or double focusing mass spectrometer. In this review the characteristics and analytical features, some recent developments, and applications of laser ionization mass spectrometry in inorganic trace analysis are described. (orig.)

Laser ionization mass spectrometry in inorganic trace analysis

International Nuclear Information System (INIS)

Becker, J.S.; Dietze, H.J.

1992-01-01

Among the different spectrometric techniques for trace analysis Laser Ionization Mass Spectrometry (LIMS) is well established as a trace analytical method. With the LIMS technique the sample material is evaporated and ionized by means of a focused pulsed laser in a laser microplasma, which is formed in the spot area of the irradiated sample. All chemical elements in the sample materials are evaporated and ionized in the laser plasma. The ions formed are separated according to their mass and energy by a time-of-flight, quadrupole or double focusing mass spectrometer. In this review the characteristics and analytical features, some recent developments and applications of laser ionization mass spectrometry in inorganic trace analysis are described. (orig.)

Assessment of an on-line CI-mass spectrometer as a continuous emission monitor for sewage sludge incinerators

International Nuclear Information System (INIS)

Campbell, K.R.; Hallett, D.J.; Resch, R.J.; Villinger, J.; Federer, V.

1991-01-01

ELI Eco Technologies Inc. tested two sewage sludge incinerators using regulator methods and a V and F CIMS-500 chemical ionization mass spectrometer. Correlations between dioxins and dibenzofurans from the regulatory MM5 trains and the continuous readings form the CIMS-500 for chlorobenzenes and chlorophenols were noted. As well, correlations between chlorinated organics and other volatile organics were obvious under poor combustion conditions. ELI Eco Technologies Inc. recently completed an extensive survey of organic chemical emissions including VOCs, chlorobenzenes, chlorophenols, chlorinated dioxins and dibenzofurans from two sewage sludge incinerators. The program was funded by the Municipality of Metro Toronto, Environment Ontario, and Environment Canada. Contaminants were measured by regulatory methods (ASME Modified Method 5) and simultaneously with the continuous mass spectrometer. The purpose of the study was to provide regulatory testing and at the same time evaluate the usefulness of the CIMS-500 mass spectrometer in assessing emissions. This paper describes the evaluation of the usefulness of this mass spectrometer

Gas chromatographic quadrupole time-of-flight full scan high resolution mass spectrometric screening of human urine in antidoping analysis

NARCIS (Netherlands)

Abushareeda, Wadha; Lyris, Emmanouil; Kraiem, Suhail; Wahaibi, Aisha Al; Alyazidi, Sameera; Dbes, Najib; Lommen, Arjen; Nielen, Michel; Horvatovich, Peter L.; Alsayrafi, Mohammed; Georgakopoulos, Costas

2017-01-01

This paper presents the development and validation of a high-resolution full scan (FS) electron impact ionization (EI) gas chromatography coupled to quadrupole Time-of-Flight mass spectrometry (GC/QTOF) platform for screening anabolic androgenic steroids (AAS) in human urine samples. The World

The Ramsey method in high-precision mass spectrometry with Penning traps Experimental results

CERN Document Server

George, S; Herfurth, F; Herlert, A; Kretzschmar, M; Nagy, S; Schwarz, S; Schweikhard, L; Yazidjian, C

2007-01-01

The highest precision in direct mass measurements is obtained with Penning trap mass spectrometry. Most experiments use the interconversion of the magnetron and cyclotron motional modes of the stored ion due to excitation by external radiofrequency-quadrupole fields. In this work a new excitation scheme, Ramsey's method of time-separated oscillatory fields, has been successfully tested. It has been shown to reduce significantly the uncertainty in the determination of the cyclotron frequency and thus of the ion mass of interest. The theoretical description of the ion motion excited with Ramsey's method in a Penning trap and subsequently the calculation of the resonance line shapes for different excitation times, pulse structures, and detunings of the quadrupole field has been carried out in a quantum mechanical framework and is discussed in detail in the preceding article in this journal by M. Kretzschmar. Here, the new excitation technique has been applied with the ISOLTRAP mass spectrometer at ISOLDE/CERN fo...

Miniature mass analyzer

CERN Document Server

Cuna, C; Lupsa, N; Cuna, S; Tuzson, B

2003-01-01

The paper presents the concept of different mass analyzers that were specifically designed as small dimension instruments able to detect with great sensitivity and accuracy the main environmental pollutants. The mass spectrometers are very suited instrument for chemical and isotopic analysis, needed in environmental surveillance. Usually, this is done by sampling the soil, air or water followed by laboratory analysis. To avoid drawbacks caused by sample alteration during the sampling process and transport, the 'in situ' analysis is preferred. Theoretically, any type of mass analyzer can be miniaturized, but some are more appropriate than others. Quadrupole mass filter and trap, magnetic sector, time-of-flight and ion cyclotron mass analyzers can be successfully shrunk, for each of them some performances being sacrificed but we must know which parameters are necessary to be kept unchanged. To satisfy the miniaturization criteria of the analyzer, it is necessary to use asymmetrical geometries, with ion beam obl...

Laser ionization time of flight mass spectrometer for isotope mass detection and elemental analysis of materials

Science.gov (United States)

Ahmed, Nasar; Ahmed, Rizwan; Umar, Z. A.; Aslam Baig, M.

2017-08-01

In this paper we present the construction and modification of a linear time-of-flight mass spectrometer to improve its mass resolution. This system consists of a laser ablation/ionization section based on a Q-switched Nd:YAG laser (532 nm, 500 mJ, 5 ns pulse duration) integrated with a one meter linear time-of-flight mass spectrometer coupled with an electric sector and a magnetic lens and outfitted with a channeltron electron multiplier for ion detection. The resolution of the system has been improved by optimizing the accelerating potential and inserting a magnetic lens after the extraction region. The isotopes of lithium, lead and cadmium samples have been resolved and detected in accordance with their natural abundance. The capability of the system has been further exploited to determine the elemental composition of a brass alloy, having a certified composition of zinc and copper. Our results are in excellent agreement with its certified composition. This setup is found to be extremely efficient and convenient for fast analyses of any solid sample.

Onsets of nuclear deformation from measurements with the Isoltrap mass spectrometer

International Nuclear Information System (INIS)

Naimi, S.

2010-10-01

Mass measurements provide important information concerning nuclear structure. This work presents results from the pioneering Penning trap spectrometer Isoltrap at CERN-Isolde. High-precision mass measurements of neutron-rich manganese ( 58 - 66 Mn) and krypton isotopes ( 96, 97 Kr) are presented, of which the 66 Mn and 96, 97 Kr masses are measured for the first time. In particular, the mass of 97 Kr was measured using the preparation trap and required the definition of a new fit function. In the case of the manganese isotopes, the N=40 shell closure is addressed. The two-neutron-separation energies calculated from the new masses show no shell closure at N=40 but give an estimation of the proton-neutron interaction (around 0.5 MeV) responsible for the increase of collectivity and nuclear deformation in this mass region. The new krypton masses show behavior in sharp contrast with heavier neighbors where sudden and intense deformation is present, interpreted as the establishment of a nuclear quantum shape/phase transition critical-point boundary. The new masses confirm findings from nuclear mean-square charge-radius measurements up to N=60 but are at variance with conclusions from recent gamma-ray spectroscopy. Another part of this work was the design of new decay spectroscopy system behind the Isoltrap mass spectrometer. The beam purity achievable with Isoltrap will allow decay studies with γ and β detection coupled to a tape-station. This system has been mounted and commissioned with the radioactive beam 80 Rb. (author)

Evaluation of lead isotope compositions of NIST NBS 981 measured by thermal ionization mass spectrometer and multiple-collector inductively coupled plasma mass spectrometer

Directory of Open Access Journals (Sweden)

Honglin Yuan

2016-09-01

Full Text Available Because Pb isotopes can be used for tracing, they are widely used in many disciplines. The detection and analysis of Pb isotopes of bulk samples are usually conducted using thermal ionization mass spectrometer (TIMS and multiple-collector inductively coupled plasma mass spectrometer (MC-ICP-MS, both of which need external reference materials with known isotopic compositions to correct for the mass discrimination effect produced during analysis. NIST NBS 981 is the most widely used reference material for Pb isotope analysis; however, the isotopic compositions reported by various analytical laboratories, especially those using TIMS, vary from each other. In this study, we statistically evaluated 229 reported TIMS analysis values collected by GeoReM in the last 30 years, 176 reported MC-ICP-MS analysis values, and 938 MC-ICP-MS analysis results from our laboratory in the last five years. After careful investigation, only 40 TIMS results were found to have double or triple spikes. The ratios of the overall weighted averages, 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb, obtained from 40 spiked TIMS reports and 1114 MC-ICP-MS results of NIST NBS 981 isotopes were 16.9406 ± 0.0003 (2s, 15.4957 ± 0.0002 (2s, and 36.7184 ± 0.0007 (2s, respectively.

Trace analysis of pesticides in paddy field water by direct injection using liquid chromatography-quadrupole-linear ion trap-mass spectrometry.

Science.gov (United States)

Pareja, Lucía; Martínez-Bueno, M J; Cesio, Verónica; Heinzen, Horacio; Fernández-Alba, A R

2011-07-29

A multiresidue method was developed for the quantification and confirmation of 70 pesticides in paddy field water. After its filtration, water was injected directly in a liquid chromatograph coupled to a hybrid triple quadrupole-linear ion trap-mass spectrometer (QqLIT). The list of target analytes included organophosphates, phenylureas, sulfonylureas, carbamates, conazoles, imidazolinones and others compounds widely used in different countries where rice is cropped. Detection and quantification limits achieved were in the range from 0.4 to 80 ng L(-1) and from 2 to 150 ng L(-1), respectively. Correlation coefficients for the calibration curves in the range 0.1-50 μg L(-1) were higher than 0.99 except for diazinon (0.1-25 μg L(-1)). Only 9 pesticides presented more than 20% of signal suppression/enhancement, no matrix effect was observed in the studied conditions for the rest of the target pesticides. The method developed was used to investigate the occurrence of pesticides in 59 water samples collected in paddy fields located in Spain and Uruguay. The study shows the presence of bensulfuron methyl, tricyclazole, carbendazim, imidacloprid, tebuconazole and quinclorac in a concentration range from 0.08 to 7.20 μg L(-1). Copyright © 2011 Elsevier B.V. All rights reserved.

A five-collector system for the simultaneous measurement of argon isotope ratios in a static mass spectrometer

Science.gov (United States)

Stacey, J.S.; Sherrill, N.D.; Dalrymple, G.B.; Lanphere, M.A.; Carpenter, N.V.

1981-01-01

A system is described that utilizes five separate Faraday-cup collector assemblies, aligned along the focal plane of a mass spectrometer, to collect simultaneous argon ion beams at masses 36-40. Each collector has its own electrometer amplifier and analog-to-digital measuring channel, the outputs of which are processed by a minicomputer that also controls the mass spectrometer. The mass spectrometer utilizes a 90?? sector magnetic analyzer with a radius of 23 cm, in which some degree of z-direction focussing is provided for all the ion beams by the fringe field of the magnet. Simultaneous measurement of the ion beams helps to eliminate mass-spectrometer memory as a significant source of measurement error during an analysis. Isotope ratios stabilize between 7 and 9 s after sample admission into the spectrometer, and thereafter changes in the measured ratios are linear, typically to within ??0.02%. Thus the multi-collector arrangement permits very short extrapolation times for computation of initial ratios, and also provides the advantages of simultaneous measurement of the ion currents in that errors due to variations in ion beam intensity are minimized. A complete analysis takes less than 10 min, so that sample throughput can be greatly enhanced. In this instrument, the factor limiting analytical precision now lies in short-term apparent variations in the interchannel calibration factors. ?? 1981.

Comparison of linear intrascan and interscan dynamic ranges of Orbitrap and ion-mobility time-of-flight mass spectrometers.

Science.gov (United States)

Kaufmann, Anton; Walker, Stephan

2017-11-30

The linear intrascan and interscan dynamic ranges of mass spectrometers are important in metabolome and residue analysis. A large linear dynamic range is mandatory if both low- and high-abundance ions have to be detected and quantitated in heavy matrix samples. These performance criteria, as provided by modern high-resolution mass spectrometry (HRMS), were systematically investigated. The comparison included two generations of Orbitraps, and an ion mobility quadrupole time-of-flight (QTOF) system In addition, different scan modes, as provided by the utilized instruments, were investigated. Calibration curves of different compounds covering a concentration range of five orders of magnitude were measured to evaluate the linear interscan dynamic range. The linear intrascan dynamic range and the resulting mass accuracy were evaluated by repeating these measurements in the presence of a very intense background. Modern HRMS instruments can show linear dynamic ranges of five orders of magnitude. Often, however, the linear dynamic range is limited by the detection capability (sensitivity and selectivity) and by the electrospray ionization. Orbitraps, as opposed to TOF instruments, show a reduced intrascan dynamic range. This is due to the limited C-trap and Orbitrap capacity. The tested TOF instrument shows poorer mass accuracies than the Orbitraps. In contrast, hyphenation with an ion-mobility device seems not to affect the linear dynamic range. The linear dynamic range of modern HRMS instrumentation has been significantly improved. This also refers to the virtual absence of systematic mass shifts at high ion abundances. The intrascan dynamic range of the current Orbitrap technology may still be a limitation when analyzing complex matrix extracts. On the other hand, the linear dynamic range is not only limited by the detector technology, but can also be shortened by peripheral devices, where the ionization and transfer of ions take place. Copyright © 2017 John Wiley

Development and Evaluation of a Reverse-Entry Ion Source Orbitrap Mass Spectrometer

Science.gov (United States)

Poltash, Michael L.; McCabe, Jacob W.; Patrick, John W.; Laganowsky, Arthur; Russell, David H.

2018-05-01

As a step towards development of a high-resolution ion mobility mass spectrometer using the orbitrap mass analyzer platform, we describe herein a novel reverse-entry ion source (REIS) coupled to the higher-energy C-trap dissociation (HCD) cell of an orbitrap mass spectrometer with extended mass range. Development of the REIS is a first step in the development of a drift tube ion mobility-orbitrap MS. The REIS approach retains the functionality of the commercial instrument ion source which permits the uninterrupted use of the instrument during development as well as performance comparisons between the two ion sources. Ubiquitin (8.5 kDa) and lipid binding to the ammonia transport channel (AmtB, 126 kDa) protein complex were used as model soluble and membrane proteins, respectively, to evaluate the performance of the REIS instrument. Mass resolution obtained with the REIS is comparable to that obtained using the commercial ion source. The charge state distributions for ubiquitin and AmtB obtained on the REIS are in agreement with previous studies which suggests that the REIS-orbitrap EMR retains native structure in the gas phase.

Mass-spectrometer for on-line operation with an accelerator

International Nuclear Information System (INIS)

Belyaev, B.N.; Gall', L.N.; Domkin, V.D.

1974-01-01

The paper describes the most essential elements and parameters of a mass-spectrometer designed for the on-line operation with the Leningrad Institute for Nuclear Physics synchrocyclotron with an extracted 1 GeV proton beam. The mass-spectrometer consists of two sections: analytical and measuring. A thermal ionization ion source is used for measuring isotope composition of nuclear reaction alkaline products produced in a target under the effect of 19 ev protons. While the selection and development of an ion-optical system for the source a provision had to be made for a high efficiency of the device as well as a stobility of parameters of the ion-optical system. To meet these requirements a massive electrode principle formed the basis of the system. Electrodes were a slit-type system consisted of three cylindrical lenses. Anion-optical system scheme is given in the paper. The employment of the ion-optical system with a small angle divergence in the horizontal plane provided for a high resolution of the spectrometer, approximately 400 at the relative aperture of 14-16%. The target consisted of a stack of MPG-6 graphite plates (20-30 pcs), 0.1 mm thick, 9x18 mm; the plates were fixed (1x10 0.1 mm apart by means of narrow in terlayers (1x10 mm) of the same material. For ensuring optimal diffusion and ionization depending upon the chemical element under study the target was heated up to 1.500-1.900 deg C. Results were obtained on the production cross-sections of lithium (6, 7, 8, 9 Li) isotope in the carbon target. While measuring sup(7, 8, 9)Li isotope yields the target irradiation period was 15 min and for 6 Li 3 min. The background was measured for each line of a mass-spectrum with proton beam off. The results obtained for the lithium isotope production cross section are of interests for discussions on problems of the light element production in cosmic rays

Global study of quadrupole correlation effects

International Nuclear Information System (INIS)

Bender, M.; Bertsch, G.F.; Heenen, P.-H.

2006-01-01

We discuss the systematics of ground-state quadrupole correlations of binding energies and mean-square charge radii for all even-even nuclei, from 16 O up to the superheavies, for which data are available. To that aim we calculate their correlated J=0 ground state by means of the angular-momentum and particle-number projected generator coordinate method, using the axial mass quadrupole moment as the generator coordinate and self-consistent mean-field states restricted only by axial, parity, and time-reversal symmetries. The calculation is performed within the framework of a nonrelativistic self-consistent mean-field model by use of the same Skyrme interaction SLy4 and to a density-dependent pairing force to generate the mean-field configurations and to mix them. These are the main conclusions of our study: (i) The quadrupole correlation energy varies between a few 100 keV and about 5.5 MeV. It is affected by shell closures, but varies only slightly with mass and asymmetry. (ii) Projection on angular momentum J=0 provides the major part of the energy gain of up to about 4 MeV; all nuclei in the study, including doubly magic ones, gain energy by deformation. (iii) The mixing of projected states with different intrinsic axial deformations adds a few 100 keV up to 1.5 MeV to the correlation energy. (iv) Typically nuclei below mass A≤60 have a larger correlation energy than static deformation energy whereas the heavier deformed nuclei have larger static deformation energy than correlation energy. (v) Inclusion of the quadrupole correlation energy improves the description of mass systematics, particularly around shell closures, and of differential quantities, namely two-nucleon separation energies and two-nucleon gaps. The correlation energy provides an explanation of 'mutually enhanced magicity'. (vi) The correlation energy tends to decrease the shell effect on binding energies around magic numbers, but the magnitude of the suppression is not large enough to explain

Continuous flow isotope ratio mass spectrometer (CF-IRMS) and its applications in hydrocarbon research and exploration

International Nuclear Information System (INIS)

Kalpana, G.; Patil, D.J.; Kumar, B.

2004-01-01

Stable isotope ratio mass spectrometers have been widely used to determine the isotopic ratios of light elements such as hydrogen, carbon, nitrogen, oxygen and sulphur. Continuous Flow Isotope Ratio Mass Spectrometry (CFIRMS) provides reliable data on nanomole amount of sample gas without the need for cryogenic trapping using cold fingers as in dual inlet isotope ratio mass spectrometer. High sample throughput is achieved as the system is configured with automated sample preparation devices and auto samplers. This paper presents a brief description of CFIRMS exploration

A high precision mass spectrometer for hydrogen isotopic analysis of water samples

International Nuclear Information System (INIS)

Murthy, M.S.; Prahallada Rao, B.S.; Handu, V.K.; Satam, J.V.

1979-01-01

A high precision mass spectrometer with two ion collector assemblies and direct on line reduction facility (with uranium at 700 0 C) for water samples for hydrogen isotopic analysis has been designed and developed. The ion source particularly gives high sensitivity and at the same tike limits the H 3 + ions to a minimum. A digital ratiometer with a H 2 + compensator has also been developed. The overall precision obtained on the spectrometer is 0.07% 2sub(sigmasub(10)) value. Typical results on the performance of the spectrometer, which is working since a year and a half are given. Possible methods of extending the ranges of concentration the spectrometer can handle, both on lower and higher sides are discussed. Problems of memory between samples are briefly listed. A multiple inlet system to overcome these problems is suggested. This will also enable faster analysis when samples of highly varying concentrations are to be analyzed. A few probable areas in which the spectrometer will be shortly put to use are given. (auth.)

Mechanism of ion output for the MI-1305 mass-spectrometer

Energy Technology Data Exchange (ETDEWEB)

Kornyushkin, YW D; Stavrovich, N V [Leningradskij Inst. Tochnoj Mekhaniki i Optiki (USSR)

1976-01-01

An attachment to MJ-1305 mass-spectrometer for ion ejection enabling to study interaction of ions and substance is designed. The attachment is accomodated with a block of diaphragms forming a beam of primary ions. A magneto-discharge pump has been used to improve vacuum in a sample chamber up to 5x10/sup -8/ torr. An universal exit slit permits producing ion beam currents ranging from 10/sup -9/ to 10/sup -10/ A with 4 keV energy under operating conditions of the spectrometer as an ion source. To ensure a higher noise stability of the measuring circuit the ion current is measured through a variable signal with synchronous detection employed.

Set-up with electrostatic analyzer for mass spectrometers

International Nuclear Information System (INIS)

Ivanov, V.P.; Sysoev, A.A.; Samsonov, G.A.

1977-01-01

An attachment with an electrostatic analyzer that enables to implement a double focusing of ion beams when used in conjunction with a magnetic analyzer, is suggested. Used as the electrostatic analyzer is a cylindrical capacitor placed in a vacuum chamber. Apart from this, the attachment includes a vacuum pump, a nitrogen trap, a battery supply unit, one-beam ion receivers and a bellows inlet for capacitor adjustment. All assemblies and parts of the attachment are made of stainless steel. The test of a combined operation of the mass-spactrometer and the attachment indicate that the use of the attachment enables the utilization of sources which form ion beams with an energy dispersion of up to 1.5%, the mass-spectrometer resolving power being unchanged

Real-Time Food Authentication Using a Miniature Mass Spectrometer.

Science.gov (United States)

Gerbig, Stefanie; Neese, Stephan; Penner, Alexander; Spengler, Bernhard; Schulz, Sabine

2017-10-17

Food adulteration is a threat to public health and the economy. In order to determine food adulteration efficiently, rapid and easy-to-use on-site analytical methods are needed. In this study, a miniaturized mass spectrometer in combination with three ambient ionization methods was used for food authentication. The chemical fingerprints of three milk types, five fish species, and two coffee types were measured using electrospray ionization, desorption electrospray ionization, and low temperature plasma ionization. Minimum sample preparation was needed for the analysis of liquid and solid food samples. Mass spectrometric data was processed using the laboratory-built software MS food classifier, which allows for the definition of specific food profiles from reference data sets using multivariate statistical methods and the subsequent classification of unknown data. Applicability of the obtained mass spectrometric fingerprints for food authentication was evaluated using different data processing methods, leave-10%-out cross-validation, and real-time classification of new data. Classification accuracy of 100% was achieved for the differentiation of milk types and fish species, and a classification accuracy of 96.4% was achieved for coffee types in cross-validation experiments. Measurement of two milk mixtures yielded correct classification of >94%. For real-time classification, the accuracies were comparable. Functionality of the software program and its performance is described. Processing time for a reference data set and a newly acquired spectrum was found to be 12 s and 2 s, respectively. These proof-of-principle experiments show that the combination of a miniaturized mass spectrometer, ambient ionization, and statistical analysis is suitable for on-site real-time food authentication.

Ion optics of a high resolution multipassage mass spectrometer with electrostatic ion mirrors

Energy Technology Data Exchange (ETDEWEB)

Sakurai, T [Osaka Univ. (Japan). Dept. of Physics; Baril, M [Departement de Physique, Faculte des Sciences et de Genie, Universite Laval, Ste-Foy, Quebec G1K 7P4 (Canada)

1995-09-01

Ion trajectories in an electrostatic ion mirror are calculated. The interferences of the extended fringing fields of the mirror with finite aperture are studied. The results of the calculations are represented by three transfer matrices, which describe ion trajectories under the effects of a fringing field at the entrances, of an idealized mirror region, and of a fringing field at the exit. The focusing effects and ion-optical properties of mass spectrometers with electrostatic ion mirrors can be evaluated by using these transfer matrices. A high performance multipassage mass spectrometer is designed. The system has one magnet and four electrostatic sector analyzers and two ion mirrors. The double focusing condition and stigmatic focusing condition are achieved in any passage of the system. The mass resolution increases linearly with the number of passages in a magnet. (orig.).

Precise mass measurements of astrophysical interest made with the Canadian Penning trap mass spectrometer

International Nuclear Information System (INIS)

Clark, J.A.; Barber, R.C.; Blank, B.; Boudreau, C.; Buchinger, F.; Crawford, J.E.; Gulick, S.; Hardy, J.C.; Heinz, A.; Lee, J.K.P.; Levand, A.F.; Moore, R.B.; Savard, G.; Seweryniak, D.; Sharma, K.S.; Sprouse, G.D.; Trimble, W.; Vaz, J.; Wang, J.C.; Zhou, Z.

2004-01-01

The processes responsible for the creation of elements more massive than iron are not well understood. Possible production mechanisms involve the rapid capture of protons (rp-process) or the rapid capture of neutrons (r-process), which are thought to occur in explosive astrophysical events such as novae, x-ray bursts, and supernovae. Mass measurements of the nuclides involved with uncertainties on the order of 100 keV or better are critical to determine the process 'paths', the energy output of the events, and the resulting nuclide abundances. Particularly important are the masses of 'waiting-point' nuclides along the rp-process path where the process stalls until the subsequent β decay of the nuclides. This paper will discuss the precise mass measurements made of isotopes along the rp-process and r-process paths using the Canadian Penning Trap mass spectrometer, including the mass of the critical waiting-point nuclide 68 Se

Mass spectrometer provided with an optical system for separating neutron particles against charged particles

Energy Technology Data Exchange (ETDEWEB)

Reeher, J R; Story, M S; Smith, R D

1977-03-03

This invention concerns a mass spectrometer with an ion focusing optical system that efficiently separates the charged and neutral particles. It concerns an apparatus that can be used in ionisation areas operating at relatively high pressure (> 10/sup -2/ Torr). The invention relates more particularly to a mass spectrometer with an inlet device for the samples to be identified, a sample ionisation system for forming charged and neutral particles, a mass analyser and an optical system for focusing the ions formed in the mass analyser. The optics include several conducting components of which at least one has sides formed of grids, in the direction of the axis, towards the analyser the optics forming a potential well along the axis. The selected charged particles are focused in the analyser and the remaining particles can escape by the openings in the conducting grids.

Identification of chemical warfare agents from vapor samples using a field-portable capillary gas chromatography/membrane-interfaced electron ionization quadrupole mass spectrometry instrument with Tri-Bed concentrator.

Science.gov (United States)

Nagashima, Hisayuki; Kondo, Tomohide; Nagoya, Tomoki; Ikeda, Toru; Kurimata, Naoko; Unoke, Shohei; Seto, Yasuo

2015-08-07

A field-portable gas chromatograph-mass spectrometer (Hapsite ER system) was evaluated for the detection of chemical warfare agents (CWAs) in the vapor phase. The system consisted of Tri-Bed concentrator gas sampler (trapping time: 3s(-1)min), a nonpolar low thermal-mass capillary gas chromatography column capable of raising temperatures up to 200°C, a hydrophobic membrane-interfaced electron ionization quadrupole mass spectrometer evacuated by a non-evaporative getter pump for data acquisition, and a personal computer for data analysis. Sample vapors containing as little as 22μg sarin (GB), 100μg soman (GD), 210μg tabun (GA), 55μg cyclohexylsarin (GF), 4.8μg sulfur mustard, 390μg nitrogen mustard 1, 140μg of nitrogen mustard 2, 130μg nitrogen mustard 3, 120μg of 2-chloroacetophenone and 990μg of chloropicrin per cubic meter could be confirmed after Tri-Bed micro-concentration (for 1min) and automated AMDIS search within 12min. Using manual deconvolution by background subtraction of neighboring regions on the extracted ion chromatograms, the above-mentioned CWAs could be confirmed at lower concentration levels. The memory effects were also examined and we found that blister agents showed significantly more carry-over than nerve agents. Gasoline vapor was found to interfere with the detection of GB and GD, raising the concentration limits for confirmation in the presence of gasoline by both AMDIS search and manual deconvolution; however, GA and GF were not subject to interference by gasoline. Lewisite 1, and o-chlorobenzylidene malononitrile could also be confirmed by gas chromatography, but it was hard to quantify them. Vapors of phosgene, chlorine, and cyanogen chloride could be confirmed by direct mass spectrometric detection at concentration levels higher than 2, 140, and 10mg/m(3) respectively, by bypassing the micro-concentration trap and gas chromatographic separation. Copyright © 2015 Elsevier B.V. All rights reserved.

Quadrupole moments of wobbling excitations in 163Lu

International Nuclear Information System (INIS)

Goergen, A.; Clark, R.M.; Cromaz, M.; Fallon, P.; Lee, I.Y.; Macchiavelli, A.O.; Ward, D.; Hagemann, G.B.; Sletten, G.; Huebel, H.; Bengtsson, R.

2004-01-01

Lifetimes of states in the triaxial strongly deformed bands of 163 Lu have been measured with the Gammasphere spectrometer using the Doppler-shift attenuation method. The bands have been interpreted as wobbling-phonon excitations from the characteristic electromagnetic properties of the transitions connecting the bands. Quadrupole moments are extracted for the zero-phonon yrast band and, for the first time, for the one-phonon wobbling band. The very similar results found for the two bands suggest a similar intrinsic structure and support the wobbling interpretation. While the in-band quadrupole moments for the bands show a decreasing trend towards higher spin, the ratio of the interband to the in-band transition strengths remains constant. Both features can be understood by a small increase in triaxiality towards higher spin. Such a change in triaxiality is also found in cranking calculations, to which the experimental results are compared

Multiple-ion-beam time-of-flight mass spectrometer

International Nuclear Information System (INIS)

Rohrbacher, Andreas; Continetti, Robert E.

2001-01-01

An innovative approach to increase the throughput of mass spectrometric analyses using a multiple-ion-beam mass spectrometer is described. Two sample spots were applied onto a laser desorption/ionization target and each spot was simultaneously irradiated by a beam of quadrupled Nd:YLF laser radiation (261.75 nm) to produce ions by laser-desorption ionization. Acceleration of the ions in an electric field created parallel ion beams that were focused by two parallel einzel lens systems. After a flight path of 2.34 m, the ions were detected with a microchannel plate-phosphor screen assembly coupled with a charge coupled device camera that showed two resolved ion beams. Time-of-flight mass spectra were also obtained with this detector. Experiments were performed using both metal atom cations (Ti + and Cr + ) produced by laser desorption/ionization and the molecular ions of two different proteins (myoglobin and lysozyme), created by matrix assisted laser desorption/ionization using an excess of nicotinic acid as matrix

Computerized mass spectrometer data system at LLL

International Nuclear Information System (INIS)

Friesen, R.D.; Dupzyk, R.J.

1976-01-01

The data systems on the three mass spectrometers at LLL are computer-controlled, pulse-counting systems synchronized to a repeatedly swept magnetic field. The data are accumulated in the memory of the computer or in a Nuclear Data ND 180 in a multi-scaler mode of operation. This mode of data acquisition allows a continuous check of the background stability and makes tune-up easier. But the main benefit is a reduction in the required ion emission rate stability. By the use of standards to set the system dead time, we have been able to utilize the sensitivity of a pulse counting system without the expense of exotic equipment

Differential fragmentation patterns of pectin oligogalacturonides observed by nanoelectrospray quadrupole ion-trap mass spectrometry using automated spectra interpretation

DEFF Research Database (Denmark)

Mutenda, Kudzai E; Matthiesen, Rune; Roepstorff, Peter

2007-01-01

Oligogalacturonides of different degrees of polymerization (DP) and methyl esterification (DE) were structurally analyzed by nanoESI quadrupole ion-trap mass spectrometry. The fragmentation patterns of the oligogalacturonides were compared using the program 'Virtual Expert Mass Spectrometrist...... with free carboxylic acid groups underwent higher water loss compared to fully methyl-esterified oligogalacturonides under the same fragmentation conditions. Cross-ring cleavage, in which fragmentation occurs across the ring system of the galacturonate residue and signified by unique mass losses...... water loss than methyl-esterified ones will be postulated. In addition, the VEMS program was extended to automatically interpret and assign the fragment ions peaks generated in this study....

Tandem mass spectrometry at low kinetic energy

International Nuclear Information System (INIS)

Cooks, R.G.; Hand, O.W.

1987-01-01

Recent progress in mass spectrometry, as applied to molecular analysis, is reviewed with emphasis on tandem mass spectrometry. Tandem instruments use multiple analyzers (sector magnets, quadrupole mass filters and time-of-flight devices) to select particular molecules in ionic form, react them in the gas-phase and then record the mass, momenta or kinetic energies of their products. The capabilities of tandem mass spectrometry for identification of individual molecules or particular classes of compounds in complex mixtures are illustrated. Several different types of experiments can be run using a tandem mass spectrometer; all share the feature of sifting the molecular mixture being analyzed on the basis of chemical properties expressed in terms of ionic mass, kinetic energy or charge state. Applications of mass spectrometry to biological problems often depend upon desorption methods of ionization in which samples are bombarded with particle beams. Evaporation of preformed charged species from the condensed phase into the vacuum is a particularly effective method of ionization. It is suggested that the use of accelerator mass spectrometers be extended to include problems of molecular analysis. In such experiments, low energy tandem mass spectrometry conducted in the eV or keV range of energies, would be followed by further characterization of the production ion beam using high selective MeV collision processes

Dustbuster: a New Generation Impact-ionization Time-of-flight Mass Spectrometer for in situ Analysis of Cosmic Dust

Science.gov (United States)

Austin, D. E.; Ahrens, T. J.; Beauchamp, J. L.

2000-10-01

We have developed and tested a small impact-ionization time-of-flight mass spectrometer for analysis of cosmic dust, suitable for use on deep space missions. This mass spectrometer, named Dustbuster, incorporates a large target area and a reflectron, simultaneously optimizing mass resolution, sensitivity, and collection efficiency. Dust particles hitting the 65-cm2 target plate are partially ionized. The resulting ions are accelerated through a modified reflectron that focuses the ions in space and time to produce high-resolution spectra. The instrument, shown below, measures 10 x 10 x 20 cm, has a mass of 500 g, and consumes little power. Laser desorption ionization of metal and mineral samples (embedded in the impact plate) simulates particle impacts for instrument performance tests. Mass resolution in these experiments is near 200, permitting resolution of isotopes. The mass spectrometer can be combined with other instrument components to determine dust particle trajectories and sizes. This project was funded by NASA's Planetary Instrument Definition and Development Program.

Isotopic dependence of the giant quadrupole resonance in the stable even-mass molybdenum nuclei

International Nuclear Information System (INIS)

Moalem, A.; Gaillard, Y.; Bemolle, A.M.; Buenerd, M.; Chauvin, J.; Duhamel, G.; Lebrun, D.; Martin, P.; Perrin, G.; de Saintignon, P.

1979-01-01

Inelastic scattering of 110 MeV 3 He particles is used to probe the quadrupole strength in the even Mo isotopes. The peak position of the giant quadrupole resonance is found to decrease more rapidly than predicted by the A/sup -1/3/ law, a behavior very similar to that exhibited by the photonuclear giant dipole resonance. The width and strength of the giant quadrupole resonance are practically constant in 92 Mo through 100 Mo

Methane measurement by the Pioneer Venus large probe neutral mass spectrometer

Science.gov (United States)

Donahue, T. M.; Hodges, R. R., Jr.

1992-12-01

The Pioneer Venus Large Probe Mass Spectrometer detected a large quantity of methane as it descended below 20 km in the atmosphere of Venus. Terrestrial methane and Xe-136, both originating in the same container and flowing through the same plumbing, were deliberately released inside the mass spectrometer for instrumental reasons. However, the Xe-136 did not exhibit behavior similar to methane during Venus entry, nor did CH4 in laboratory simulations. The CH4 was deuterium poor compared to Venus water and hydrogen. While the inlet to the mass spectrometer was clogged with sulfuric acid droplets, significant deuteration of CH4 and its H2 progeny was observed. Since the only source of deuterium identifiable was water from sulfuric acid, we have concluded that we should correct the HDO/H2O ratio in Venus water from 3.2 x 10-2 to (5 plus or minus 0.7) x 10-2. When the probe was in the lower atmosphere, transfer of deuterium from Venus HDO and HD to CH4 can account quantitatively for the deficiencies recorded in HDO and HD below 10 km, and consequently, the mysterious gradients in water vapor and hydrogen mixing ratios we have reported. The revision in the D/H ratio reduces the mixing ratio of water vapor (and H2) reported previously by a factor of 3.2/5. We are not yet able to say whether the methane detected was atmospheric or an instrumental artifact. If it was atmospheric, its release must have been episodic and highly localized. Otherwise, the large D/H ratio in Venus water and hydrogen could not be maintained.

Identification of isomers and control of ionization and dissociation processes using dual-mass-spectrometer scheme and genetic algorithm optimization

International Nuclear Information System (INIS)

Chen Zhou; Qiu-Nan Tong; Zhang Cong-Cong; Hu Zhan

2015-01-01

Identification of acetone and its two isomers, and the control of their ionization and dissociation processes are performed using a dual-mass-spectrometer scheme. The scheme employs two sets of time of flight mass spectrometers to simultaneously acquire the mass spectra of two different molecules under the irradiation of identically shaped femtosecond laser pulses. The optimal laser pulses are found using closed-loop learning method based on a genetic algorithm. Compared with the mass spectra of the two isomers that are obtained with the transform limited pulse, those obtained under the irradiation of the optimal laser pulse show large differences and the various reaction pathways of the two molecules are selectively controlled. The experimental results demonstrate that the scheme is quite effective and useful in studies of two molecules having common mass peaks, which makes a traditional single mass spectrometer unfeasible. (paper)

Depth-resolved sample composition analysis using laser-induced ablation-quadrupole mass spectrometry and laser-induced breakdown spectroscopy

Science.gov (United States)

Oelmann, J.; Gierse, N.; Li, C.; Brezinsek, S.; Zlobinski, M.; Turan, B.; Haas, S.; Linsmeier, Ch.

2018-06-01

Monitoring a sample's material composition became more and more important over the last years for both - industrial process control as well as for post mortem analysis in research and industrial development. Although material composition identification as well as a comparison with standard samples works fine, there is a lack of diagnostics which can provide quantitative information with depth resolution without any standard samples. We present a novel method utilizing a residual gas analysis with quadrupole mass spectrometry after picosecond laser-induced ablation and release of volatile species. In the present experiment, well characterized multilayer thin film solar cells (μc-Si:H and a-Si:D as p-i-n-junctions on ZnO:Al electrodes) are used as a set of well characterized material samples to demonstrate the capabilities of the new method. The linearity of the spectrometer signal to gas pressure simplifies its calibration and reduces its uncertainties in comparison with other analysis techniques, although high vacuum conditions (10-6 hPa to 10-7 hPa) are required to reach high sensitivity better than the percent-range. Moreover, the laser-ablation based sample analysis requires no preparation of the sample and is flexible regarding ablation rates. The application of a picosecond laser pulse ensures that the thermal penetration depth of the laser is in the same order of magnitude as the ablation rate, which enables to achieve depth resolutions in the order of 100 nm and avoids matrix mixing effects at the edge of the laser-induced crater in the sample.

Miniature Time of Flight Mass Spectrometer for Space and Extraterrestrial Applications, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — The PI has developed a miniature time-of-flight mass spectrometer (TOF-MS), which can be op-timized for space and extraterrestrial applications, by using a...

Performance of the Recoil Mass Spectrometer and its detector systems at the Holifield Radioactive Ion Beam Facility

International Nuclear Information System (INIS)

Gross, C.J.; Ginter, T.N.; Shapira, D.; Milner, W.T.; McConnell, J.W.; James, A.N.; Johnson, J.W.; Mas, J.; Mantica, P.F.; Auble, R.L.; Das, J.J.; Blankenship, J.L.; Hamilton, J.H.; Robinson, R.L.; Akovali, Y.A.; Baktash, C.; Batchelder, J.C.; Bingham, C.R.; Brinkman, M.J.; Carter, H.K.; Cunningham, R.A.; Davinson, T.; Fox, J.D.; Galindo-Uribarri, A.; Grzywacz, R.; Liang, J.F.; MacDonald, B.D.; MacKenzie, J.; Paul, S.D.; Piechaczek, A.; Radford, D.C.; Ramayya, A.V.; Reviol, W.; Rudolph, D.; Rykaczewski, K.; Toth, K.S.; Weintraub, W.; Williams, C.; Woods, P.J.; Yu, C.-H.; Zganjar, E.F.

2000-01-01

The recently commissioned Recoil Mass Spectrometer (RMS) at the Holifield Radioactive Ion Beam Facility (HRIBF) is described. Consisting of a momentum separator followed by an E-D-E Rochester-type mass spectrometer, the RMS is the centerpiece of the nuclear structure endstation at the HRIBF. Designed to transport ions with rigidities near K=100, the RMS has acceptances of ±10% in energy and ±4.9% in mass-to-charge ratio. Recent experimental results are used to illustrate the detection capabilities of the RMS, which is compatible with many detectors and devices

Precise determination of cosmogenic Ne in CREU-1 quartz standard, using the Helix-MC Plus mass spectrometer

Science.gov (United States)

Hamilton, D.; Honda, M.; Zhang, X.; Phillips, D.; Matchan, E.

2017-12-01

The Helix-MC Plus multi-collector noble gas mass spectrometer at the Australian National University is uniquely equipped with three high mass resolution collectors on H2, Axial and L2 positions. Their mass resolution and mass resolving power are as high as 1,800 and 8,000, respectively. The Helix-MC Plus can totally separate 20Ne+ from 40Ar++ isobaric interference and also partially separate 21Ne+ from 20NeH+ and 22Ne+ from 12C16O2++. By adjusting collector positions, we are able to measure interference-free Ne isotope intensities and have re-determined the 21Ne abundance in air [1]. Analyses by Honda et al. [1] demonstrated that 20Ne1H contributes approximately 2% to previously determined atmospheric 21Ne values [2], and a new atmospheric 21Ne/20Ne ratio of 0.002906 was calculated. Using the Helix-MC Plus mass spectrometer, we measured Ne abundances in the CREU-1 quartz standard [3] and determined cosmogenic concentrations by subtraction of atmospheric Ne with the new atmospheric 21Ne/20Ne value. The average concentration of cosmogenic 21Ne determined from four repeated analyses is 338 ± 12 × 106 atom/g (2σ). This compares with the average concentration of 348 ± 10 × 106 atom/g (2σ) from 45 analyses determined by several laboratories [3], where Ne isotope analyses were undertaken by conventional low resolution mass spectrometers and atmospheric Ne was subtracted using the conventional atmospheric 21Ne/20Ne [2]. On this basis, for a sample with abundant cosmogenic Ne, like CREU-1 quartz, previously measured by low mass resolution mass spectrometers are likely valid and their geological implications are unaffected. However, for low 21Ne concentration samples, combining new generation of mass spectrometers as well as the new atmospheric ratio may have significance for cosmogenic 21Ne surface exposure dating. References: [1] Honda M., et. al., International Journal of Mass Spectrometry, 387, 1 (2015). [2] Eberhardt P., et. al., Zeitschrift fur Naturforschung, 20

Extermination Of Uranium Isotopes Composition Using A Micro Computer With An IEEE-488 Interface For Mass Spectrometer Analysis

International Nuclear Information System (INIS)

Prajitno; Taftazani, Agus; Yusuf

1996-01-01

A mass spectrometry method can be used to make qualitative or quantitative analysis. For qualitative analysis, identification of unknown materials by a Mass Spectrometer requires definite assignment of mass number to peak on chart. In quantitative analysis, a mass spectrometer is used to determine isotope composition material in the sample. Analysis system of a Mass Spectrometer possession of PPNY-BATAN based on comparison ion current intensity which enter the collector, and have been used to analyse isotope composition. Calculation of isotope composition have been manually done. To increase the performance and to avoid manual data processing, a micro computer and IEEE-488 interface have been installed, also software packaged has been made. So that the determination of the isotope composition of material in the sample will be faster and more efficient. Tile accuracy of analysis using this program on sample standard U 3 O 8 NBS 010 is between 93,87% - 99,98%

Direct mass measurements of light neutron-rich nuclei using fast recoil spectrometers

International Nuclear Information System (INIS)

Vieira, D.J.; Wouters, J.M.

1987-01-01

Extensive new mass measurement capabilities have evolved with the development of recoil spectrometers. In the Z = 3 to 9 neutron-rich region alone, 12 neutron-rich nuclei have been determined for the first time by the fast-recoil direct mass measurement method. A recent experiment using the TOFI spectrometer illustrates this technique. A systematic investigation of nuclei that lie along or near the neutron-drip line has provided a valuable first glimpse into the nuclear structure of such nuclei. No evidence for a large single-particle energy gap at N = 14 is observed; however, a change in the two-neutron separation model calculations, and is interpreted in terms of the smaller 1s/sub 1/2/ - 1s/sub 1/2/ interaction compared to that of the 0d/sub 5/2/ - 0d/sub 5/2/ neutron-neutron interaction. 18 refs., 7 figs., 1 tab

Gas chromatography interfaced with atmospheric pressure ionization-quadrupole time-of-flight-mass spectrometry by low-temperature plasma ionization

DEFF Research Database (Denmark)

Norgaard, Asger W.; Kofoed-Sorensen, Vivi; Svensmark, Bo

2013-01-01

A low temperature plasma (LTP) ionization interface between a gas chromatograph (GC) and an atmospheric pressure inlet mass spectrometer, was constructed. This enabled time-of-flight mass spectrometric detection of GC-eluting compounds. The performance of the setup was evaluated by injection...

Feasibility of a Fieldable Mass Spectrometer FY 2015 Year-end Report

Energy Technology Data Exchange (ETDEWEB)

Barinaga, Charles J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hager, George J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hoegg, Edward D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carman, April J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hart, Garret L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-10-01

Currently, the International Atomic Energy Agency (IAEA) monitors the production of enriched uranium hexafluoride (UF₆) at declared facilities by collecting a few grams of product in sample tubes that are then sent to central laboratories for processing and isotope ratio analysis by thermal ionization mass spectrometry. Analysis of results may not be available for some time after collection. In addition, new shipping regulations will make it more difficult to transport this amount of UF₆ to a laboratory. The IAEA is interested in an isotope ratio technique for uranium in UF₆ that can be moved to and operated at the enrichment facility itself. This report covers the tasks and activities of the Feasibility of a Fieldable Mass Spectrometer Project for FY 2015, which investigates the feasibility of an in-field isotope ratio technique— the forward deployment of a technique to the non-laboratory situation of a protected room with power and heat at the facility of interest. A variety of nontraditional elemental ionization techniques were considered. It was determined that only two of these should be moved forward for testing with the candidate in-field mass spectrometer and with the adsorbed UF₆ sample types.

A fully automated mass spectrometer for the analysis of organic solids

International Nuclear Information System (INIS)

Hillig, H.; Kueper, H.; Riepe, W.

1979-01-01

Automation of a mass spectrometer-computer system makes it possible to process up to 30 samples without attention after sample loading. An automatic sample changer introduces the samples successively into the ion source by means of a direct inlet probe. A process control unit determines the operation sequence. Computer programs are available for the hardware support, system supervision and evaluation of the spectrometer signals. The most essential precondition for automation - automatic evaporation of the sample material by electronic control of the total ion current - is confirmed to be satisfactory. The system operates routinely overnight in an industrial laboratory, so that day work can be devoted to difficult analytical problems. The cost of routine analyses is halved. (Auth.)

A specialized isotope mass spectrometer for noninvasive diagnostics of Helicobacter pylori infection in human beings

Science.gov (United States)

Blashenkov, N. M.; Sheshenya, E. S.; Solov'ev, S. M.; Sachenko, V. D.; Gall, L. N.; Zarutskii, I. V.; Gall, N. R.

2013-05-01

A specialized isotope mass spectrometer for noninvasive diagnostics of Helicobacter pylori infection in human beings based on the carbon-13 isotope breath test has been designed and constructed. Important stages of the work included (i) calculating a low-aberration mass analyzer, (ii) manufacturing and testing special gas inlet system, and (iii) creating a small-size collector of ions. The proposed instrument ensures 13C/12C isotopic ratio measurement to within 1.7‰ (pro mille) accuracy, which corresponds to requirements for a diagnostic tool. Preliminary medical testing showed that the mass spectrometer is applicable to practical diagnostics. The instrument is also capable of measuring isotopic ratios of other light elements, including N, O, B (for BF2+ ions), Ar, Cl, and S.

In situ analysis of corrosion inhibitors using a portable mass spectrometer with paper spray ionization.

Science.gov (United States)

Jjunju, Fred P M; Li, Anyin; Badu-Tawiah, Abraham; Wei, Pu; Li, Linfan; Ouyang, Zheng; Roqan, Iman S; Cooks, R Graham

2013-07-07

Paper spray (PS) ambient ionization is implemented using a portable mass spectrometer and applied to the detection of alkyl quaternary ammonium salts in a complex oil matrix. These salts are commonly used as active components in the formulation of corrosion inhibitors. They were identified in oil and confirmed by their fragmentation patterns recorded using tandem mass spectrometry (MS/MS). The cations of alkyl and benzyl-substituted quaternary ammonium salts showed characteristic neutral losses of CnH2n (n carbon number of the longest chain) and C7H8, respectively. Individual quaternary ammonium compounds were detected at low concentrations (oil samples without prior sample preparation or pre-concentration was also demonstrated using a home-built miniature mass spectrometer at levels below 1 ng μL(-1).

Chemical analysis of surfaces by resonance ionization mass spectroscopy associated to ionic pulverization

International Nuclear Information System (INIS)

Kern, P.

1995-01-01

This work shows that if resonance ionization mass spectroscopy was first applied in isotopic separation, it's also an analyzing method adapted to the study of semi-conductor materials and thin foils. We have improved this technic: a neodymium laser coupled with a dye laser, a new argon ions gun, a gallium ions gun and a new collection optic for the secondary ions quadrupole spectrometer to allow quantitative and selective measurements. (S.G.). 84 refs

Determination of molybdenum in plant reference material by thermal-ionization isotope-dilution mass spectrometry

International Nuclear Information System (INIS)

Saumer, M.; Gantner, E.; Reinhardt, J.; Ache, H.J.

1992-01-01

An analytical method is described for the determination of the concentration and the isotopic composition of molybdenum in plant samples using thermal ionization mass spectrometry. After microwave acid digestion and liquid-liquid extractive separation with Amberlite LA-2, the molybdenum isotopes are measured as MoO 3 - -ions in a quadrupole mass spectrometer. In all cases, the relative standard deviation of the measurements of both natural and spike molybdenum was better than 3% for all ratios measured. The concentration of molybdenum found in three different plant reference materials agreed well with the certified values. (orig.)

Collisional damping of giant monopole and quadrupole resonances

International Nuclear Information System (INIS)

Yildirim, S.; Gokalp, A.; Yilmaz, O.; Ayik, S.

2001-01-01

Collisional damping widths of giant monopole and quadrupole excitations for 120 Sn and 208 Pb at zero and finite temperatures are calculated within Thomas-Fermi approximation by employing the microscopic in-medium cross-sections of Li and Machleidt and the phenomenological Skyrme and Gogny forces, and are compared with each other. The results for the collisional widths of giant monopole and quadrupole vibrations at zero temperature as a function of the mass number show that the collisional damping of giant monopole vibrations accounts for about 30 - 40% of the observed widths at zero temperature, while for giant quadrupole vibrations it accounts for only 20 - 30% of the observed widths at zero temperature. (orig.)

The Assessment of Selectivity in Different Quadrupole-Orbitrap Mass Spectrometry Acquisition Modes

Science.gov (United States)

Berendsen, Bjorn J. A.; Wegh, Robin S.; Meijer, Thijs; Nielen, Michel W. F.

2015-02-01

Selectivity of the confirmation of identity in liquid chromatography (tandem) mass spectrometry using Q-Orbitrap instrumentation was assessed using different acquisition modes based on a representative experimental data set constructed from 108 samples, including six different matrix extracts and containing over 100 analytes each. Single stage full scan, all ion fragmentation, and product ion scanning were applied. By generating reconstructed ion chromatograms using unit mass window in targeted MS2, selected reaction monitoring (SRM), regularly applied using triple-quadrupole instruments, was mimicked. This facilitated the comparison of single stage full scan, all ion fragmentation, (mimicked) SRM, and product ion scanning applying a mass window down to 1 ppm. Single factor Analysis of Variance was carried out on the variance (s2) of the mass error to determine which factors and interactions are significant parameters with respect to selectivity. We conclude that selectivity is related to the target compound (mainly the mass defect), the matrix, sample clean-up, concentration, and mass resolution. Selectivity of the different instrumental configurations was quantified by counting the number of interfering peaks observed in the chromatograms. We conclude that precursor ion selection significantly contributes to selectivity: monitoring of a single product ion at high mass accuracy with a 1 Da precursor ion window proved to be equally selective or better to monitoring two transition products in mimicked SRM. In contrast, monitoring a single fragment in all ion fragmentation mode results in significantly lower selectivity versus mimicked SRM. After a thorough inter-laboratory evaluation study, the results of this study can be used for a critical reassessment of the current identification points system and contribute to the next generation of evidence-based and robust performance criteria in residue analysis and sports doping.

Quantitative Determination of Bioactive Constituents in Noni Juice by High-performance Liquid Chromatography with Electrospray Ionization Triple Quadrupole Mass Spectrometry.

Science.gov (United States)

Yan, Yongqiu; Lu, Yu; Jiang, Shiping; Jiang, Yu; Tong, Yingpeng; Zuo, Limin; Yang, Jun; Gong, Feng; Zhang, Ling; Wang, Ping

2018-01-01

Noni juice has been extensively used as folk medicine for the treatment of arthritis, infections, analgesic, colds, cancers, and diabetes by Polynesians for many years. Due to the lack of standard scientific evaluation methods, various kinds of commercial Noni juice with different quality and price were available on the market. To establish a sensitive, reliable, and accurate high-performance liquid chromatography with electrospray ionization triple quadrupole mass spectrometry (HPLC-ESI-MS/MS) method for separation, identification, and simultaneous quantitative analysis of bioactive constituents in Noni juice. The analytes and eight batches of commercially available samples from different origins were separated and analyzed by the HPLC-ESI-MS/MS method on an Agilent ZORBAX SB-C 18 (150 mm × 4.6 mm i.d., 5 μm) column using a gradient elution of acetonitrile-methanol-0.05% glacial acetic acid in water (v/v) at a constant flow rate of 0.5 mL/min. Seven components were identification and all of the assay parameters were within the required limits. Components were within the correlation coefficient values ( R 2 ≥ 0.9993) at the concentration ranges tested. The precision of the assay method was high-performance liquid chromatography with electrospray ionization triple quadrupole mass spectrometryThe presented method was successfully applied to the quality control of eight batches of commercially available samples of Noni juiceThis method is simple, sensitive, reliable, accurate, and efficient method with strong specificity, good precision, and high recovery rate and provides a reliable basis for quality control of Noni juice. Abbreviations used: HPLC-ESI-MS/MS: High-performance liquid chromatography with electrospray ionization triple quadrupole mass spectrometry, LOD: Limit of detection, LOQ: Limit of quantitation, S/N: Signal-to-noise ratio, RSD: Relative standard deviations, DP: Declustering potential, CE: Collision energy, MRM: Multiple reaction monitoring, RT

The LHC Main Quadrupoles during Series Fabrication

CERN Document Server

Tortschanoff, Theodor; Durante, M; Hagen, P; Klein, U; Krischel, D; Payn, A; Rossi, L; Schellong, B; Schmidt, P; Simon, F; Schirm, K-M; Todesco, E

2006-01-01

By the end of August 2005 about 320 of the 400 main LHC quadrupole magnets have been fabricated and about 220 of them assembled into their cold masses, together with corrector magnets. About 130 of them have been cold tested in their cryostats and most of the quadrupoles exceeded their nominal excitation, i.e. 12,000 A, after no more than two training quenches. During this series fabrication, the quality of the magnets and cold masses was thoroughly monitored by means of warm magnetic field measurements, of strict geometrical checking, and of various electrical verifications. A number of modifications were introduced in order to improve the magnet fabrication, mainly correction of the coil geometry for achieving the specified field quality and measures for avoiding coil insulation problems. Further changes concern the electrical connectivity and insulation of instrumentation, and of the corrector magnets inside the cold masses. The contact resistances for the bus-bar connections to the quench protection diode...

Accurate Mass GC/LC-Quadrupole Time of Flight Mass Spectrometry Analysis of Fatty Acids and Triacylglycerols of Spicy Fruits from the Apiaceae Family

Directory of Open Access Journals (Sweden)

Thao Nguyen

2015-12-01

Full Text Available The triacylglycerol (TAG structure and the regio-stereospecific distribution of fatty acids (FA of seed oils from most of the Apiaceae family are not well documented. The TAG structure ultimately determines the final physical properties of the oils and the position of FAs in the TAG molecule affects the digestion; absorption and metabolism; and physical and technological properties of TAGs. Fixed oils from the fruits of dill (Anethum graveolens, caraway (Carum carvi, cumin (Cuminum cyminum, coriander (Coriandrum sativum, anise (Pimpinella anisum, carrot (Daucus carota, celery (Apium graveolens, fennel (Foeniculum vulgare, and Khella (Ammi visnaga, all from the Apiaceae family, were extracted at room temperature in chloroform/methanol (2:1 v/v using percolators. Crude lipids were fractionated by solid phase extraction to separate neutral triacylglycerols (TAGs from other lipids components. Neutral TAGs were subjected to transesterification process to convert them to their corresponding fatty acids methyl esters (FAMES using 1% boron trifluoride (BF3 in methanol. FAMES were analyzed by gas chromatography-quadrupole time of flight (GC-QTOF mass spectrometry. Triglycerides were analyzed using high performance liquid chromatography-quadrupole time of flight (LC-QTOF mass spectrometry. Petroselinic acid was the major fatty acid in all samples ranging from 57% of the total fatty acids in caraway up to 82% in fennel. All samples contained palmitic (16:0, palmitoleic (C16:1n-9, stearic (C18:0, petroselinic (C18:1n-12, linoleic (C18:2n-6, linolinic (18:3n-3, and arachidic (C20:0 acids. TAG were analyzed using LC-QTOF for accurate mass identification and mass spectrometry/mass spectrometry (MS/MS techniques for regiospesific elucidation of the identified TAGs. Five major TAGs were detected in all samples but with different relative concentrations in all of the tested samples. Several other TAGs were detected as minor components and were present in some

A Method for Estimating Mass-Transfer Coefficients in a Biofilter from Membrane Inlet Mass Spectrometer Data

DEFF Research Database (Denmark)

Nielsen, Anders Michael; Nielsen, Lars Peter; Feilberg, Anders

2009-01-01

A membrane inlet mass spectrometer (MIMS) was used in combination with a developed computer model to study and improve management of a biofilter (BF) treating malodorous ventilation air from a meat rendering facility. The MIMS was used to determine percentage removal efficiencies (REs) of selected...... sulfur gases and to provide toluene retention profiles for the model to determine the air velocity and overall mass-transfer coefficient of toluene. The mass-transfer coefficient of toluene was used as a reference for determining the mass transfer of sulfur gases. By presenting the model to scenarios...... of a filter bed with a consortium of effective sulfur oxidizers, the most likely mechanism for incomplete removal of sulfur compounds from the exhaust air was elucidated. This was found to be insufficient mass transfer and not inadequate bacterial activity as anticipated by the manager of the BF. Thus...

Metabolic profiling of Hoodia, Chamomile, Terminalia Species and evaluation of commercial preparations using Ultra-High Performance Quadrupole Time of Flight-Mass Spectrometry

Science.gov (United States)

Ultra-High Performance-Quadrupole Time of Flight Mass Spectrometr(UHPLC-QToF-MS)profiling has become an impattant tool for identification of marker compounds and generation of metabolic patterns that could be interrogated using chemometric modeling software. Chemometric approaches can be used to ana...

HPLC-UV ATMOSPHERIC-PRESSURE IONIZATION MASS-SPECTROMETRIC DETERMINATION OF THE DOPAMINE-D2 AGONIST N-0923 AND ITS MAJOR METABOLITES AFTER OXIDATIVE-METABOLISM BY RAT-LIVER, MONKEY LIVER, AND HUMAN LIVER-MICROSOMES

NARCIS (Netherlands)

SWART, PJ; BRONNER, GM; BRUINS, AP; ENSING, K; TEPPER, PG; DEZEEUW, RA

1993-01-01

An innovative custom-built atmospheric ionization source afforded an opportunity to perform on-line LC/MS analysis and to obtain identification of metabolites without need to rely on radioactive profiling. An HPLC with a UV detector coupled to a modified R 3010 triple quadrupole mass spectrometer

Proof of Concept Coded Aperture Miniature Mass Spectrometer Using a Cycloidal Sector Mass Analyzer, a Carbon Nanotube (CNT) Field Emission Electron Ionization Source, and an Array Detector

Science.gov (United States)

Amsden, Jason J.; Herr, Philip J.; Landry, David M. W.; Kim, William; Vyas, Raul; Parker, Charles B.; Kirley, Matthew P.; Keil, Adam D.; Gilchrist, Kristin H.; Radauscher, Erich J.; Hall, Stephen D.; Carlson, James B.; Baldasaro, Nicholas; Stokes, David; Di Dona, Shane T.; Russell, Zachary E.; Grego, Sonia; Edwards, Steven J.; Sperline, Roger P.; Denton, M. Bonner; Stoner, Brian R.; Gehm, Michael E.; Glass, Jeffrey T.

2018-02-01

Despite many potential applications, miniature mass spectrometers have had limited adoption in the field due to the tradeoff between throughput and resolution that limits their performance relative to laboratory instruments. Recently, a solution to this tradeoff has been demonstrated by using spatially coded apertures in magnetic sector mass spectrometers, enabling throughput and signal-to-background improvements of greater than an order of magnitude with no loss of resolution. This paper describes a proof of concept demonstration of a cycloidal coded aperture miniature mass spectrometer (C-CAMMS) demonstrating use of spatially coded apertures in a cycloidal sector mass analyzer for the first time. C-CAMMS also incorporates a miniature carbon nanotube (CNT) field emission electron ionization source and a capacitive transimpedance amplifier (CTIA) ion array detector. Results confirm the cycloidal mass analyzer's compatibility with aperture coding. A >10× increase in throughput was achieved without loss of resolution compared with a single slit instrument. Several areas where additional improvement can be realized are identified.

Direct Laser Ablation and Ionization of Solids for Chemical Analysis by Mass Spectrometry

Energy Technology Data Exchange (ETDEWEB)

Holt, J K; Nelson, E J; Klunder, G L [Forensic Science Center, Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States)

2007-04-15

A laser ablation/ionization mass spectrometer system is described for the direct chemical analysis of solids. An Nd:YAG laser is used for ablation and ionization of the sample in a quadrupole ion trap operated in an ion-storage (IS) mode that is coupled with a reflectron time-of-flight mass spectrometer (TOF-MS). Single pulse experiments have demonstrated simultaneous detection of up to 14 elements present in glasses in the ppm range. However, detection of the components has produced non-stoichiometric results due to difference in ionization potentials and fractionation effects. Time-of-flight secondary ionization mass spectrometry (TOF-SIMS) was used to spatially map elemental species on the surface and provide further evidence of fractionation effects. Resolution (m/{delta}m) of 1500 and detection limits of approximately 10 pg have been achieved with a single laser pulse. The system configuration and related operating principles for accurately measuring low concentrations of isotopes are described.

Onsets of nuclear deformation from measurements with the Isoltrap mass spectrometer

CERN Document Server

Naimi, Sarah

Mass measurements provide important information concerning nuclear structure. This work presents results from the pioneering Penning trap spectrometer ISOLTRAP at CERN-ISOLDE. High-precision mass measurements of neutron-rich manganese ($^{58−66}$Mn) and krypton isotopes ($^{96,97}$Kr) are presented, of which the $^{66}$Mn and $^{96,97}$Kr masses are measured for the first time. In particular, the mass of $^{97}$Kr was measured using the preparation trap and required the definition of a new fit function. In the case of the manganese isotopes, the N = 40 shell closure is addressed. The two-neutron-separation energies calculated from the new masses show no shell closure at N = 40 but give an estimation of the proton-neutron interaction (around 0.5 MeV) responsible for the increase of collectivity and nuclear deformation in this mass region. The new krypton masses show behavior in sharp contrast with heavier neighbors where sudden and intense deformation is present, interpreted as the establishment of a nuclea...

ISABELLE insertion quadrupoles

International Nuclear Information System (INIS)

Kaugerts, J.; Polk, I.; Sampson, W.; Dahl, P.F.

1979-01-01

Beam focussing and control at the beam intersection regions of ISABELLE is accomplished by a number of superconducting insertion quadrupoles. These magnets differ from the standard ISABELLE quadrupoles in various ways. In particular, the requirements of limited space near the intersections and aperture for beam extraction impose constraints on their configuration. To achieve optimum beam focussing and provide tuning flexibility calls for stronger quadrupole trim windings than those in the standard quadrupoles. The magnetic and mechanical design of the insertion quadrupoles and their associated correction and steering windings to accomplish the above tasks is presented

Characterization of goat colostrum oligosaccharides by nano-liquid chromatography on chip quadrupole time-of-flight mass spectrometry and hydrophilic interaction liquid chromatography-quadrupole mass spectrometry.

Science.gov (United States)

Martín-Ortiz, A; Salcedo, J; Barile, D; Bunyatratchata, A; Moreno, F J; Martin-García, I; Clemente, A; Sanz, M L; Ruiz-Matute, A I

2016-01-08

A detailed qualitative and quantitative characterization of goat colostrum oligosaccharides (GCO) has been carried out for the first time. Defatted and deproteinized colostrum samples, previously treated by size exclusion chromatography (SEC) to remove lactose, were analyzed by nanoflow liquid chromatography-quadrupole-time of flight mass spectrometry (Nano-LC-Chip-Q-TOF MS). Up to 78 oligosaccharides containing hexose, hexosamine, fucose, N-acetylneuraminic acid or N-glycolylneuraminic acid monomeric units were identified in the samples, some of them detected for the first time in goat colostra. As a second step, a hydrophilic interaction liquid chromatography coupled to mass spectrometry (HILIC-MS) methodology was developed for the separation and quantitation of the main GCO, both acidic and neutral carbohydrates. Among other experimental chromatographic conditions, mobile phase additives and column temperature were evaluated in terms of retention time, resolution, peak width and symmetry of target carbohydrates. Narrow peaks (wh: 0.2-0.6min) and good symmetry (As: 0.8-1.4) were obtained for GCO using an acetonitrile:water gradient with 0.1% ammonium hydroxide at 40°C. These conditions were selected to quantify the main oligosaccharides in goat colostrum samples. Values ranging from 140 to 315mgL(-1) for neutral oligosaccharides and from 83 to 251mgL(-1) for acidic oligosaccharides were found. The combination of both techniques resulted to be useful to achieve a comprehensive characterization of GCO. Copyright © 2015 Elsevier B.V. All rights reserved.

Portable mass spectrometer for express analysis of dissolved in water substances

International Nuclear Information System (INIS)

Kogan, V.T.; Pavlov, A.K.; Savchenko, M.I.; Dobychin, O.E.

1999-01-01

The mass spectrometer for analysis under field conditions of chemical composition of dissolved in water substances is described. Special attention is paid to developing portable mass analyzer and device for a probe inlet. The device is intended for the systems of direct autonomous control of water basins contamination. Depending on the level of required work degree of autonomy and loading rate of the device, its dimensions and consumption way vary. The tests of the pilot device having 370x420x570 mm size, 23 kg mass and ≤ 40 W consumption capacity were carried out. The resolution capacity of the device is 100 (at the level of ≤ 3%) and relative sensitivity - ≤ 10 -6 [ru

Atmospheric pressure gas chromatography coupled to quadrupole-time of flight mass spectrometry as a powerful tool for identification of non intentionally added substances in acrylic adhesives used in food packaging materials.

Science.gov (United States)

Canellas, E; Vera, P; Domeño, C; Alfaro, P; Nerín, C

2012-04-27

Acrylic adhesives are used to manufacture multilayer laminates that are used in food packaging to form the geometric shape of the package as well as to stick labels on the packages. Once applied on the packaging adhesives can supply potential migrants that could endanger the packaged food. Adhesives are complex matrices where intentionally and non intentionally added substances are present, but the identification of the migrants is required by law. In this study atmospheric pressure gas chromatography coupled to a quadrupole hyphenated to a time of flight mass spectrometer (APGC-MS/Q-TOF) has been explored for identification of unknowns coming from three different acrylic adhesives. The results are compared to those obtained by conventional GC-MS-Q (quadrupole). Sixteen compounds were identified by GC-MS/Q and five of them were confirmed by APGC-MS/Q-TOF as their molecular ions were found. Moreover, additional three new compounds were identified and their structure was elucidated working with the spectra obtained by APGC-MS/Q-TOF. This finding was very relevant as these compounds were biocides suspected to be allergenic and cytotoxic in humans. Migration studies were carried out using Tenax as solid food simulant and the results showed that the three acrylic adhesives tested in this work were safe for being used in food packaging materials since the migration of compounds previously identified was below the limit established in the current legislation. Copyright © 2012 Elsevier B.V. All rights reserved.

Linear electric field time-of-flight ion mass spectrometer

Science.gov (United States)

Funsten, Herbert O [Los Alamos, NM; Feldman, William C [Los Alamos, NM

2008-06-10

A linear electric field ion mass spectrometer having an evacuated enclosure with means for generating a linear electric field located in the evacuated enclosure and means for injecting a sample material into the linear electric field. A source of pulsed ionizing radiation injects ionizing radiation into the linear electric field to ionize atoms or molecules of the sample material, and timing means determine the time elapsed between ionization of atoms or molecules and arrival of an ion out of the ionized atoms or molecules at a predetermined position.

Development of a sensitive method for the determination of acrylamide in coffee using high-performance liquid chromatography coupled to a hybrid quadrupole Orbitrap mass spectrometer.

Science.gov (United States)

Pugajeva, Iveta; Jaunbergs, Janis; Bartkevics, Vadims

2015-01-01

The emerging trend towards high-resolution mass spectrometry (MS) alternatives was evaluated by the application of Orbitrap MS for the determination of acrylamide in coffee samples. The high resolving power of the Orbitrap MS provided the high selectivity and sensitivity that enabled quantitative analysis of acrylamide in complex matrices, such as coffee. Several sample preparation methods and scanning modes of the MS (full MS, t-SIM, t-MS2) were assessed in order to optimise parameters of the analytical method. The final procedure involved the extraction of acrylamide with acetonitrile, solid-phase extraction with dispersive primary secondary amine (PSA) and amino columns, and the detection by ultra-performance liquid chromatography coupled to a hybrid quadrupole-Orbitrap MS (HPLC-Q-Orbitrap) operated in targeted MS2 scanning mode. The repeatability of the method at the lowest calibration level (10 μg kg(-1)), expressed as relative standard deviation, was 7.8% and the average recovery of acrylamide was 111%. The proposed method was applied to the determination of acrylamide in 22 samples of roasted coffee obtained from the Latvian retail market. Acrylamide concentration in coffee samples was in the range of 166-503 μg kg(-1).

Virtual Models of Mass Spectrometers as Teaching Tools for Graduate Students.

Directory of Open Access Journals (Sweden)

L. Gomes da Silva

2010-05-01

Full Text Available Universidade Federal do Rio de Janeiro – UFRJ – Campus Macaé- RJMass spectrometry is an analytical powerful technique for identifying unknowns, quantitating knows and discovering chemicals properties and molecular structures. The mass spectrometry concept is very simple: The sample becomes an ion through an ionization method. Ions are selected by mass to charge ratio (m/z based upon the motion in a magnetic field and each one is register under a spectrum. To access the basic of these techniques by using appropriate literature, videos, virtual models and simulations for this machinesbehavior is today´s exclusiveness for researchers through manufacturer handbooks. This reality becomes the science popularization and knowledge diffusion about proteomic analysis something plenty arduous for the portion or part of graduate students. The work objectives were making a multimediaschool-book showing biochemical techniques for proteomic analysis using mass spectrometry. The material was make with specific software for building 3D models and animation of different ionizations methods: Electron Ionization (EI, Electro spray Ionization (ESI, Atmospheric Pressure Chemical Ionization(APCI, Matrix Assisted Laser Desorption/Ionization (MALD and mass analyzers: Time of Flight(TOF, Quadrupole and Ion Trap.

Physical design of time-of-flight mass spectrometer in energetic cluster impact deposition apparatus

International Nuclear Information System (INIS)

Yu Guoqing; Shi Ying; Chen Jingsheng; Zhu Dezhang; Pan Haochang; Xu Hongjie

1999-01-01

The principle and physical design of the time-of-flight mass spectrometer equipped in the energetic cluster impact deposition apparatus are introduced. Some problems existed in experiments and their solutions are also discussed

Effective mass trigger at the Brookhaven Multi-Particle Spectrometer (MPS)

International Nuclear Information System (INIS)

Willen, E.H.

1980-01-01

An effective mass trigger for use at the Brookhaven Multiparticle Spectrometer (MPS) is described. It is a microprocessor based device using extensive fast memory attached to proportional wire chambers in the MPS magnetic field. It will select kinematic quantities unique to the reaction being studied, thereby permitting higher sensitivities and a reduction in data-processing cost for MPS experiments. The principles of operation for this trigger, and the results of simulations to assess its performance, are presented

Rescuing the nonjet (NJ) azimuth quadrupole from the flow narrative

Science.gov (United States)

Trainor, Thomas A.

2017-04-01

According to the flow narrative commonly applied to high-energy nuclear collisions a cylindrical-quadrupole component of 1D azimuth angular correlations is conventionally denoted by quantity υ2 and interpreted to represent elliptic flow. Jet angular correlations may also contribute to υ2 data "nonflow" depending on the method used to calculate υ2, but 2D graphical methods are available to insure accurate separation. The nonjet (NJ) quadrupole has various properties inconsistent with a flow interpretation, including the observation that NJ quadrupole centrality variation in A-A collisions has no relation to strongly-varying jet modication ("jet quenching") in those collisions commonly attributed to jet interaction with a flowing dense medium. In this presentation I describe isolation of quadrupole spectra from pt-differential υ2(pt) data from the RHIC and LHC. I demonstrate that quadrupole spectra have characteristics very different from the single-particle spectra for most hadrons, that quadrupole spectra indicate a common boosted hadron source for a small minority of hadrons that "carry" the NJ quadrupole structure, that the narrow source-boost distribution is characteristic of an expanding thin cylindrical shell (strongly contradicting hydro descriptions), and that in the boost frame a single universal quadrupole spectrum (Lévy distribution) on transverse mass mt accurately describes data for several hadron species scaled according to their statistical-model abundances. The quadrupole spectrum shape changes very little from RHIC to LHC energies. Taken in combination those characteristics strongly suggest a unique nonflow (and nonjet) QCD mechanism for the NJ quadrupole conventionally represented by υ2.

Rescuing the nonjet (NJ azimuth quadrupole from the flow narrative

Directory of Open Access Journals (Sweden)

Trainor Thomas A.

2017-01-01

Full Text Available According to the flow narrative commonly applied to high-energy nuclear collisions a cylindrical-quadrupole component of 1D azimuth angular correlations is conventionally denoted by quantity υ2 and interpreted to represent elliptic flow. Jet angular correlations may also contribute to υ2 data “nonflow” depending on the method used to calculate υ2, but 2D graphical methods are available to insure accurate separation. The nonjet (NJ quadrupole has various properties inconsistent with a flow interpretation, including the observation that NJ quadrupole centrality variation in A-A collisions has no relation to strongly-varying jet modication (“jet quenching” in those collisions commonly attributed to jet interaction with a flowing dense medium. In this presentation I describe isolation of quadrupole spectra from pt-differential υ2(pt data from the RHIC and LHC. I demonstrate that quadrupole spectra have characteristics very different from the single-particle spectra for most hadrons, that quadrupole spectra indicate a common boosted hadron source for a small minority of hadrons that “carry” the NJ quadrupole structure, that the narrow source-boost distribution is characteristic of an expanding thin cylindrical shell (strongly contradicting hydro descriptions, and that in the boost frame a single universal quadrupole spectrum (Lévy distribution on transverse mass mt accurately describes data for several hadron species scaled according to their statistical-model abundances. The quadrupole spectrum shape changes very little from RHIC to LHC energies. Taken in combination those characteristics strongly suggest a unique nonflow (and nonjet QCD mechanism for the NJ quadrupole conventionally represented by υ2.

Regiospecific analysis of neutral ether lipids by liquid chromatography/electrospray ionization/single quadrupole mass spectrometry: validation with synthetic compounds

DEFF Research Database (Denmark)

Hartvigsen, Karsten; Ravandi, A.; Bukhave, Klaus

2001-01-01

A reversed-phase high-performance liquid chromatography (HPLC) method with on-line electrospray ionization/collision-induced dissociation/mass spectrometry (ESI/CID/MS) is presented for the regiospecific analysis of synthetic reference compounds of neutral ether lipids. The reference compounds were...... characterized by chromatographic retention times, full mass spectra, and fragmentation patterns as an aid to clarify the regiospecificity of ether lipids from natural sources. The results clearly show that single quadrupole mass spectroscopic analysis may elucidate the regiospecific structure of neutral ether...... + H - H2O](+), whereas the reverse situation characterized the sn-3 species. Furthermore, corresponding sn-2 and sn-3 species were separated by the chromatographic system. However, loss of water was promoted as fatty acid unsaturation was raised, which may complicate interpretation of the mass spectra...

MacMS: A Mass Spectrometer Simulator: Abstract of Issue 9906M

Science.gov (United States)

Bigger, Stephen W.; Craig, Robert A.

1999-10-01

MacMS is a program for Mac-OS compatible computers that simulates a magnetic sector mass spectrometer (1-4) designed to operate in the mass-to-charge (m/z) ratio range of 1-200 amu. MacMS has two operational modules. The first module (see Figure 1) is called the "Path" module and enables the user to quantitatively examine the trajectory of an ion of given m/z ratio in the electric and magnetic fields of the simulated "instrument". By systematically measuring a series of trajectories of different ions under different electric and magnetic field conditions, the user can determine how the resolution of the "instrument" is affected by these experimentally variable parameters. The user can thus choose suitable instrumental conditions for scanning a given m/z ratio range with good separation between the peaks. The second module (see Figure 2) is called as the "Spectrometer" module and enables the user to record, under any chosen instrumental conditions, the mass spectrum of (i) the instrumental background, (ii) neon, (iii) methane, or (iv) the parent ion of carbon tetrachloride. Both voltage scanning and magnetic scanning are possible (5). A hard copy of any mass spectrum that has been recorded can also be obtained. MacMS can read ASCII data files containing mass spectral information of compounds other than those that are "built-in" to the simulator. The appropriate format for creating such data files is described in the program documentation. There are a number of instructional exercises that can be conducted using the mass spectral information contained within the simulator. These are included in the program documentation. For example, the intensities of the 20Ne+, 21Ne+, and 22Ne+ species can be determined from hard copies of mass spectra of neon that are obtained under different instrumental sensitivities. The relative abundances of the three isotopes of neon can thus be calculated and compared with the literature values (6). The simulator also includes adjustable

SUMS preliminary design and data analysis development. [shuttle upper atmosphere mass spectrometer experiment

Science.gov (United States)

Hinson, E. W.

1981-01-01

The preliminary analysis and data analysis system development for the shuttle upper atmosphere mass spectrometer (SUMS) experiment are discussed. The SUMS experiment is designed to provide free stream atmospheric density, pressure, temperature, and mean molecular weight for the high altitude, high Mach number region.

A generic approach for expanding homolog-targeted residue screening of sulfonamides using a fast matrix separation and class-specific fragmentation-dependent acquisition with a hybrid quadrupole-linear ion trap mass spectrometer

Energy Technology Data Exchange (ETDEWEB)

Huang Chunlin [Department of Biochemistry and Molecular Biology, School of Pharmacy and Life Science, University of South China, Hengyang 421001 (China); Guo Bin, E-mail: binnguo@126.com [Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), Hunan Normal University, Changsha 410081 (China); Wang Xiaoying [Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), Hunan Normal University, Changsha 410081 (China); Li Jie [Department of Biochemistry and Molecular Biology, School of Pharmacy and Life Science, University of South China, Hengyang 421001 (China); Zhu Weitao; Chen Bo [Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), Hunan Normal University, Changsha 410081 (China); Ouyang Shan [Food Inspection and Quarantine Center, Shenzhen Entry-Exit Inspection and Quarantine Bureau of the People' s Republic of China, Shenzhen 518067 (China); Yao Shouzhuo [Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), Hunan Normal University, Changsha 410081 (China)

2012-08-06

Highlights: Black-Right-Pointing-Pointer Generic homolog-targeted screening approach for multi-residual sulfonamide analogs. Black-Right-Pointing-Pointer Single-tube extraction/partitioning-multifunction adsorption cleanup for direct injection. Black-Right-Pointing-Pointer Class-specific fragmentation for expanding coverage of N{sup 4}-acetyl and N-OH metabolites. Black-Right-Pointing-Pointer PreS-IDA-EPI in LC-QqLIT for simultaneous screening and confirmation of real samples. - Abstract: A generic and efficient homolog-targeted approach was used to expand screening and detection of target class of sulfonamides and structural analogs, based on a fast single-tube extraction/partitioning-multifunction adsorption cleanup (SEP/MAC) for class-specific fragmentation-dependent acquisition with a liquid chromatography-hybrid triple-quadrupole linear ion trap mass spectrometer (LC-QqLIT). By combining the two-stage process conducted in a single tube as one-pot protocol, the straightforward SEP/MAC procedure was optimized to offer clean extracts with reasonable recovery (71-109% with RSDs < 20%) and decreased matrix interferences (-9 to 19%) of multiresidual sulfonamide extraction from different tissue samples. The novel use of neutral loss scan of 66 Da (NLS) or precursor ion scanning of m/z 108 (PreS) in positive ion mode was found to achieve more comprehensive coverage of protonated molecular ions of a wide array of sulfonamides including N{sup 4}-acetyl and hydroxylamine metabolites plus their possible dimers. Moreover, the PreS-triggered automatically enhanced product ion spectral acquisition enabled simultaneous screening, profiling and confirmation of an unlimited number of analytes belonging to the sulfonamide class within a single analysis. The validation and application results of the generic SEP/MAC-based LC-QqLIT strategy consistently demonstrated favorable performances with acceptable accuracy (67-116%), precision (RSDs < 25%), and sensitivity (LOQs {<=} 7.5 ng

Algebraic formulation of collective models. I. The mass quadrupole collective model

International Nuclear Information System (INIS)

Rosensteel, G.; Rowe, D.J.

1979-01-01

This paper is the first in a series of three which together present a microscopic formulation of the Bohr--Mottelson (BM) collective model of the nucleus. In this article the mass quadrupole collective (MQC) model is defined and shown to be a generalization of the BM model. The MQC model eliminates the small oscillation assumption of BM and also yields the rotational and CM (3) submodels by holonomic constraints on the MQC configuration space. In addition, the MQC model is demonstrated to be an algebraic model, so that the state space of the MQC model carries an irrep of a Lie algebra of microscopic observables, the MQC algebra. An infinite class of new collective models is then given by the various inequivalent irreps of this algebra. A microscopic embedding of the BM model is achieved by decomposing the representation of the MQC algebra on many-particle state space into its irreducible components. In the second paper this decomposition is studied in detail. The third paper presents the symplectic model, which provides the realization of the collective model in the harmonic oscillator shell model

Method of N-15 analysis by mass-spectroscopy on ion implanter MPB-200

International Nuclear Information System (INIS)

Vo Van Thuan; Dang Duc Nhan; Nguyen Phuc; Nguyen Tien Dung; Nguyen Van Dach

1993-01-01

The industrial implanter MPB-200 has been modified to a light-isotope mass spectrometer. Mass-resolution has been improved by combination of quadrupole focusing system and a collimator with additional scattering shielding. Single beam method has been set up, in which mass-spectrum are obtained by scanning magnetic field of the separator. A start-stop control system has been added to operate automatically the magnet and registration system, from which signals are transferred to a XT/AT computer for saving and analysis. The mass-resolution is satisfactory for analysis of light isotopes with mass number A less than 40. A testing measurement has been done with standard samples of natural and enriched N-15 isotope, at acceleration energy of 50 keV, beam current less than 100 nA, vacuum of 4x10E-6 and collimator's shell of 1 mm. Obtained resolution and background condition allowed to achieve a good linear dependence of relative isotope ratio data vs real abundance in the range from natural 0.365% to 5.0% with a 3% error (96% of reliability). Routine N-15 may achieve (5-10)% accuracy by a 7-10 minutes measurement for every sample. Sensitivity of the mass-spectrometer is better almost by one order in comparing with one of emission spectrometers. The new mass-spectroscopy system is applied to research in agriculture, biology and environmental study. (author). 4 refs, 4 figs

Diagnostics aid for mass spectrometer trouble-shooting

International Nuclear Information System (INIS)

Filby, E.E.; Rankin, R.A.; Webb, G.W.

1987-01-01

The ''MS Expert'' system provides problem diagnostics for instruments used in the Mass Spectrometry Laboratory (MSL). The most critical results generated on these mass spectrometers are the uranium concentration and isotopic content data used for process control and materials accountability at the Idaho Chemical Processing Plant. The two purposes of the system are: (1) to minimize instrument downtime and thereby provide the best possible support to the Plant, and (2) to improve long-term data quality. This system combines the knowledge of several experts on mass spectrometry to provide a diagnostic tool, and can make these skills avilable on a more timely basis. It integrates code written in the Pascal language with a knowledge base entered into a commercial expert system ''shell.'' The user performs some preliminary status checks, and then selects from among several broad diagnostic categories. These initial steps provide input to the rule base. The overall analysis provides the user with a set of possible solutions to the observed problems, graded as to their probabilities. Besides the trouble-shooting benefits expected from this system, it will also provide structures diagnostic training for lab personnel. In addition, development of the system knowledge base has already produced a better understanding of instrument behavior. Two key findings are that a good user interface is necessary for full acceptance of the tool, and a development system should include standard programming capabilities as well as the expert system shell. 22 refs., 5 figs

Diagnostics aid for mass spectrometer trouble-shooting

International Nuclear Information System (INIS)

Filby, E.E.; Rankin, R.A.; Webb, G.W.

1987-01-01

The MS Expert system provides problem diagnostics for instruments used in the Mass Spectrometry Laboratory (MSL). The most critical results generated on these mass spectrometers are the uranium concentration and isotopic content data used for process control and materials accountability at the Idaho General Processing Plant. The two purposes of the system are: (1) to minimize instrument downtime and thereby provide the best possible support to the Plant, and (2) to improve long-term data quality. This system combines the knowledge of several experts on mass spectrometry to provide a diagnostic tool, and can make these skills available on a more timely basis. It integrates code written in the Pascal language with a knowledge base entered into a commercial expert system shell. The user performs some preliminary status checks, and then selects from among several broad diagnostic categories. These initial steps provide input to the rule base. The overall analysis provides the user with a set of possible solutions to the observed problems, graded as to their probabilities. Besides the trouble-shooting benefits expected from this system, it also provides structured diagnostic training for lab personnel. In addition, development of the system knowledge base has already produced a better understanding of instrument behavior. Two key findings are that a good user interface is necessary for full acceptance of the tool, and, a development system should include standard programming capabilities as well as the expert system shell

NQR spectrometer controlled by a computer

International Nuclear Information System (INIS)

Stoican, Ovidiu

2002-01-01

Nuclear quadrupole resonance (NQR) is one of the sensitive methods for studying physical and chemical properties of a substance, such as chemical composition, molecular structure, molecular motion and electronic environment. The specifications of the research project require the use of a nuclear quadrupole resonance spectrometer. Design and performances of a pulsed nuclear quadrupole resonance spectrometer prototype covering the range 1-10 MHz are presented. The pulsed NQR method offers considerably higher sensitivity than either the marginal oscillator or super-regenerative methods. Strong echoes are often observed directly with an oscilloscope or a simple receiver. The method allows us to observe two signal categories: free induction decay (fid) and echoes. The block diagram of the pulsed nuclear quadrupole resonance spectrometer is shown. All operations performed by the spectrometer are controlled by a computer. The scanning frequency range, amplitude and width of the RF pulse, additional magnetic field and sample temperature can be controlled by the software. Also it is possible to improve the signal-to-noise ratio using digital filtering applied to the data stored. Automatic operation eliminates operator skill and uncertainty of manual operation. The NQR spectrometer control software is a stand alone executable file, runs on Windows 95/98 platform and does not require the existence of another software package. A graphical interface allows to user an easy control over the spectrometer operations. All measured parameters by the control system interface are saved in the standard data files and can be processed further. The design is readily adaptable for other applications. The sample is contained within an aluminum cylindrical case. The upper end cap of the case can be removed and it allows introducing the sample. On the upper end cap RF and main temperature sensor connector are placed. On the internal side of the bottom end cap a thermoelectric cooler (MELCOR

High-precision mass measurements in the realm of the deformed shell closure N=152

Energy Technology Data Exchange (ETDEWEB)

Eibach, Martin Andreas

2013-12-04

The nuclear masses reflect the sum of all interactions inside a nucleus. Their precise knowledge can be used to benchmark nuclear mass models and to gain nuclear structure information. Penning-trap mass spectrometers have proven their potential to obtain lowest uncertainties. Uniquely located at a nuclear reactor, the double Penning-trap mass spectrometer TRIGA-TRAP is dedicated to measurements in the neutron-rich region. For a gain in sensitivity a non-destructive detection system for single ion mass measurements was adopted. This includes the implementation of a narrow band-pass filter tuned to the heavy ion cyclotron frequency as well as a cryogenic low-noise amplifier. For on-line mass measurements, the laser ablation ion source was equipped with a newly developed miniature radiofrequency quadrupole trap in order to improve the extraction efficiency. A more economic use of the radioactive material enabled mass measurements using only 10{sup 15} atoms of target material. New mass measurements were performed within this work in the realm of the deformed shell closure N=152. Their implementation into the atomic-mass evaluation improved the uncertainty of more than 80 nuclides in the heavy mass region and simultaneously shifted the absolute mass of two α decay chains.

Electrospray ionization tandem mass spectrometry of ammonium cationized polyethers.

Science.gov (United States)

Nasioudis, Andreas; Heeren, Ron M A; van Doormalen, Irene; de Wijs-Rot, Nicolette; van den Brink, Oscar F

2011-05-01

Quaternary ammonium salts (Quats) and amines are known to facilitate the MS analysis of high molar mass polyethers by forming low charge state adduct ions. The formation, stability, and behavior upon collision-induced dissociation (CID) of adduct ions of polyethers with a variety of Quats and amines were studied by electrospray ionization quadrupole time-of-flight, quadrupole ion trap, and linear ion trap tandem mass spectrometry (MS/MS). The linear ion trap instrument was part of an Orbitrap hybrid mass spectrometer that allowed accurate mass MS/MS measurements. The Quats and amines studied were of different degree of substitution, structure, and size. The stability of the adduct ions was related to the structure of the cation, especially the amine's degree of substitution. CID of singly/doubly charged primary and tertiary ammonium cationized polymers resulted in the neutral loss of the amine followed by fragmentation of the protonated product ions. The latter reveals information about the monomer unit, polymer sequence, and endgroup structure. In addition, the detection of product ions retaining the ammonium ion was observed. The predominant process in the CID of singly charged quaternary ammonium cationized polymers was cation detachment, whereas their doubly charged adduct ions provided the same information as the primary and tertiary ammonium cationized adduct ions. This study shows the potential of specific amines as tools for the structural elucidation of high molar mass polyethers. © American Society for Mass Spectrometry, 2011

A mass spectrometer for the rapid analysis of gaseous mixtures

International Nuclear Information System (INIS)

Cassignol, C.; Ortel, Y.; Taieb, J.

1950-01-01

A mass spectrometer for leak detection and rapid gas analysis were constructed, having the characteristics and several structural features of a simple instrument described by Siry in Rev. Sri. Instruments. 540 (1947). Although exhibiting a good resolving power, the apparatus, which has no ion lenses and whose electrodes can be regulated during the performance, has not been sufficiently tested. Since several design defects have been discovered, it will probably be rebuilt with various improvements (ion source outside the magnetic field, modified circuits, etc.). (author)

Use of a free-jet expansion, molecular beam mass spectrometer to understand processes involving volatile corrosion products

International Nuclear Information System (INIS)

Jacobson, N.S.

1997-01-01

Many high-temperature corrosion processes generate volatile products in addition to condensed phase products. Examples of these volatile products are chlorides, oxychlorides, and certain oxides and hydroxyl species. One of the best techniques to identify high temperature vapor molecules is mass spectrometry. Most mass spectrometers operate in high vacuum and are generally used to examine processes ocurring at greatly reduced pressures. However, a free-jet expansion, molecular beam mass spectrometer system allows direct sampling of volatile corrosion products. This instrument is described. Several examples from our studies on chlorination/oxidation of metals and ceramics are discussed. In addition, reactions of Cr 2 O 3 , SiO 2 , and Al 2 O 3 with water vapor, which produce volatile hydroxyl species are discussed. (orig.)

In situ analysis of corrosion inhibitors using a portable mass spectrometer with paper spray ionization

KAUST Repository

Jjunju, Fred Paul Mark; Li, Anyin; Badu-Tawiah, Abraham K.; Wei, Pu; Li, Linfan; Ouyang, Zheng; Roqan, Iman S.; Cooks, Robert Graham

2013-01-01

Paper spray (PS) ambient ionization is implemented using a portable mass spectrometer and applied to the detection of alkyl quaternary ammonium salts in a complex oil matrix. These salts are commonly used as active components in the formulation of corrosion inhibitors. They were identified in oil and confirmed by their fragmentation patterns recorded using tandem mass spectrometry (MS/MS). The cations of alkyl and benzyl-substituted quaternary ammonium salts showed characteristic neutral losses of CnH2n (n carbon number of the longest chain) and C7H8, respectively. Individual quaternary ammonium compounds were detected at low concentrations (<1 ng μL-1) and over a dynamic range of ∼5 pg μL-1 to 500 pg μL-1 (ppb). Direct detection of these compounds in complex oil samples without prior sample preparation or pre-concentration was also demonstrated using a home-built miniature mass spectrometer at levels below 1 ng μL-1.© 2013 The Royal Society of Chemistry.

Use of a hand-portable gas chromatograph-toroidal ion trap mass spectrometer for self-chemical ionization identification of degradation products related to O-ethyl S-(2-diisopropylaminoethyl) methyl phosphonothiolate (VX)

Energy Technology Data Exchange (ETDEWEB)

Smith, Philip A., E-mail: Smith.Philip.A@dol.gov [Uniformed Services University of the Health Sciences, Department of Preventive Medicine and Biometrics, 4301 Jones Bridge Road, Bethesda, MD, 20814 (United States); Lepage, Carmela R. Jackson [Defence R and D Canada - Suffield, Box 400, Station Main, Medicine Hat, Alberta, T1A 8K6 (Canada); Savage, Paul B. [Brigham Young University, Department of Chemistry and Biochemistry, Provo, UT, 84602 (United States); Bowerbank, Christopher R.; Lee, Edgar D. [Torion Technologies Inc., 796 East Utah Valley Drive, Suite 200, American Fork, UT, 84003 (United States); Lukacs, Michael J. [Defence R and D Canada - Suffield, Box 400, Station Main, Medicine Hat, Alberta, T1A 8K6 (Canada)

2011-04-01

The chemical warfare agent O-ethyl S-(2-diisopropylaminoethyl) methyl phosphonothiolate (VX) and many related degradation products produce poorly diagnostic electron ionization (EI) mass spectra by transmission quadrupole mass spectrometry. Thus, chemical ionization (CI) is often used for these analytes. In this work, pseudomolecular ([M+H]{sup +}) ion formation from self-chemical ionization (self-CI) was examined for four VX degradation products containing the diisopropylamine functional group. A person-portable toroidal ion trap mass spectrometer with a gas chromatographic inlet was used with EI, and both fixed-duration and feedback-controlled ionization time. With feedback-controlled ionization, ion cooling (reaction) times and ion formation target values were varied. Evidence for protonation of analytes was observed under all conditions, except for the largest analyte, bis(diisopropylaminoethyl)disulfide which yielded [M+H]{sup +} ions only with increased fixed ionization or ion cooling times. Analysis of triethylamine-d{sub 15} provided evidence that [M+H]{sup +} production was likely due to self-CI. Analysis of a degraded VX sample where lengthened ion storage and feedback-controlled ionization time were used resulted in detection of [M+H]{sup +} ions for VX and several relevant degradation products. Dimer ions were also observed for two phosphonate compounds detected in this sample.

Use of a hand-portable gas chromatograph-toroidal ion trap mass spectrometer for self-chemical ionization identification of degradation products related to O-ethyl S-(2-diisopropylaminoethyl) methyl phosphonothiolate (VX)

International Nuclear Information System (INIS)

Smith, Philip A.; Lepage, Carmela R. Jackson; Savage, Paul B.; Bowerbank, Christopher R.; Lee, Edgar D.; Lukacs, Michael J.

2011-01-01

The chemical warfare agent O-ethyl S-(2-diisopropylaminoethyl) methyl phosphonothiolate (VX) and many related degradation products produce poorly diagnostic electron ionization (EI) mass spectra by transmission quadrupole mass spectrometry. Thus, chemical ionization (CI) is often used for these analytes. In this work, pseudomolecular ([M+H] + ) ion formation from self-chemical ionization (self-CI) was examined for four VX degradation products containing the diisopropylamine functional group. A person-portable toroidal ion trap mass spectrometer with a gas chromatographic inlet was used with EI, and both fixed-duration and feedback-controlled ionization time. With feedback-controlled ionization, ion cooling (reaction) times and ion formation target values were varied. Evidence for protonation of analytes was observed under all conditions, except for the largest analyte, bis(diisopropylaminoethyl)disulfide which yielded [M+H] + ions only with increased fixed ionization or ion cooling times. Analysis of triethylamine-d 15 provided evidence that [M+H] + production was likely due to self-CI. Analysis of a degraded VX sample where lengthened ion storage and feedback-controlled ionization time were used resulted in detection of [M+H] + ions for VX and several relevant degradation products. Dimer ions were also observed for two phosphonate compounds detected in this sample.

Measurements of the microwave spectrum, Re-H bond length, and Re quadrupole coupling for HRe(CO)5

Science.gov (United States)

Kukolich, Stephen G.; Sickafoose, Shane M.

1993-11-01

Rotational transition frequencies for rhenium pentacarbonyl hydride were measured in the 4-10 GHz range using a Flygare-Balle type microwave spectrometer. The rotational constants and Re nuclear quadrupole coupling constants for the four isotopomers, (1) H187Re(CO)5, (2) H185Re(CO)5, (3) D187Re(CO)5, and (4) D185Re(CO)5, were obtained from the spectra. For the most common isotopomer, B(1)=818.5464(2) MHz and eq Q(187Re)=-900.13(3) MHz. The Re-H bond length (r0) determined by fitting the rotational constants is 1.80(1) Å. Although the Re atom is located at a site of near-octahedral symmetry, the quadrupole coupling is large due to the large Re nuclear moments. A 2.7% increase in Re quadrupole coupling was observed for D-substituted isotopomers, giving a rather large isotope effect on the quadrupole coupling. The Cax-Re-Ceq angle is 96(1)°, when all Re-C-O angles are constrained to 180°.

Rapid tryptic mapping using enzymatically active mass spectrometer probe tips

Energy Technology Data Exchange (ETDEWEB)

Dogruel, D.; Williams, P.; Nelson, R.W. [Arizona State Univ., Tempe, AZ (United States)

1995-12-01

A method has been developed for rapid, sensitive, and accurate tryptic mapping of polypeptides using matrix-assisted laser desorption/ionization time-of-flight mass analysis. The technique utilizes mass spectrometer probe tips which have been activated through the covalent immobilization of trypsin. The enzymatically active probe tips were used for the tryptic mapping of chicken egg lysozyme and the results compared with those obtained using either free trypsin or agarose-immobilized trypsin. A significant increase in the overall sensitivity of the process was observed using the active probe tips, as well as the production of more characteristic proteolytic fragments and the elimination of background signals due to the autolysis of the trypsin. Further, probe tip digestions were found to be rapid and convenient. 19 refs., 6 figs., 2 tabs.

A versatile triple radiofrequency quadrupole system for cooling, mass separation and bunching of exotic nuclei

Science.gov (United States)

Haettner, Emma; Plaß, Wolfgang R.; Czok, Ulrich; Dickel, Timo; Geissel, Hans; Kinsel, Wadim; Petrick, Martin; Schäfer, Thorsten; Scheidenberger, Christoph

2018-02-01

The combination of in-flight separation with a gas-filled stopping cell has opened a new field for experiments with exotic nuclei. For instance, at the SHIP/SHIPTRAP facility at GSI in Darmstadt high-precision mass measurements of rare nuclei have been successfully performed. In order to extend the reach of SHIPTRAP to exotic nuclei that are produced together with high rates of unwanted reaction products, a novel compact radio frequency quadrupole (RFQ) system has been developed. It implements ion cooling, identification and separation according to mass numbers and bunching capabilities. The system has a total length of one meter only and consists of an RFQ cooler, an RFQ mass filter and an RFQ buncher. A mass resolving power (FWHM) of 240 at a transmission efficiency of 90% has been achieved. The suppression of contaminants from neighboring masses by more than four orders of magnitude has been demonstrated at rates exceeding 106 ions/s. A longitudinal emittance of 0.45 eV μs has been achieved with the RFQ buncher, which will enable improved time-of-flight mass spectrometry downstream of the device. With this triple RFQ system the measurement of e.g. N= Z nuclides in the region up to tin will become possible at SHIPTRAP. The technology is also well suited for other rare-isotope facilities with experimental setups behind a stopping cell, such as the fragment separator FRS with the FRS Ion Catcher at GSI.

Measuring the mass and width of the Z0: The status of the energy spectrometers

International Nuclear Information System (INIS)

Rouse, F.; Levi, M.; Kent, J.; King, M.; Von Zanthier, C.; Watson, S.; Bambade, P.; Erickson, R.; Jung, C.K.; Nash, J.; Wormser, G.

1989-05-01

The Stanford Linear Collider (SLC) located at the Stanford Linear Accelerator Center (SLAC) collides electrons and positrons produced in the linear accelerator pulse by pulse. The object is to produce collisions energetic enough to produce the heavy intermediate vector boson, the Z 0 . An essential component of the SLC physics program is the precise knowledge of the center-of-mass energy of each interaction. We measure the energy of each collision by using two energy spectrometers. The spectrometers are located in extraction lines of each beam. We will measure the energy of each beam to 20 MeV or 5 parts in 10 4 . We report here on the status of the energy spectrometer system. 13 refs., 7 figs., 3 tabs

Performance of the rebuilt SUERC single-stage accelerator mass spectrometer

Science.gov (United States)

Shanks, Richard P.; Ascough, Philippa L.; Dougans, Andrew; Gallacher, Paul; Gulliver, Pauline; Rood, Dylan H.; Xu, Sheng; Freeman, Stewart P. H. T.

2015-10-01

The SUERC bipolar single-stage accelerator mass spectrometer (SSAMS) has been dismantled and rebuilt to accommodate an additional rotatable pre-accelerator electrostatic spherical analyser (ESA) and a second ion source injector. This is for the attachment of an experimental positive-ion electron cyclotron resonance (ECR) ion source in addition to a Cs-sputter source. The ESA significantly suppresses oxygen interference to radiocarbon detection, and remaining measurement interference is now thought to be from 13C injected as 13CH molecule scattering off the plates of a second original pre-detector ESA.

Instruction manual for ORNL tandem high abundance sensitivity mass spectrometer

International Nuclear Information System (INIS)

Smith, D.H.; McKown, H.S.; Chrisite, W.H.; Walker, R.L.; Carter, J.A.

1976-06-01

This manual describes the physical characteristics of the tandem mass spectrometer built by Oak Ridge National Laboratory for the International Atomic Energy Agency. Specific requirements met include ability to run small samples, high abundance sensitivity, good precision and accuracy, and adequate sample throughput. The instrument is capable of running uranium samples as small as 10 -12 g and has an abundance sensitivity in excess of 10 6 . Precision and accuracy are enhanced by a special sweep control circuit. Sample throughput is 6 to 12 samples per day. Operating instructions are also given

Knudsen cell--mass spectrometer studies of cesium--urania interactions

International Nuclear Information System (INIS)

Collins, J.L.; Osborne, M.F.; Malinauskas, A.P.; Lorenz, R.A.; Manning, S.R.

1976-06-01

Limited Knudsen cell--mass spectrometer studies were made of the partial pressures of cesium-containing species [assumed to be primarily Cs(g)] over Cs 2 CO 3 and over phase equilibria involving UO 2 and probable Cs-U-O compounds formed from mixtures that initially contained either Cs 2 CO 3 -UO 2 or CsOH-UO 2 . Although additional work is required to further define the equilibria involved, the data demonstrate unambiguously a significant reduction in cesium partial pressures due to probable Cs-U-O compound formation and indicate essentially identical behavior with either CsOH or Cs 2 CO 3 as the starting material with UO 2

Easy method enhancing the sensitivity of a helium mass-spectrometer leak detector

International Nuclear Information System (INIS)

Firpo, G.; Pozzo, A.

2004-01-01

Commercial He mass spectrometer leak detectors usually do not provide sufficient sensitivity to perform accurate measurements of the permeation rate of He through glass. Ultrasensitive dedicated systems have adeguate sensitivity but involve high costs and complex procedures. However, both cryogenics and photomultiplier technology routinely demand this goal. Here, we propose a novel method to increase the sensitivity of commercial devices to easily measure accurate permeation rate. We modified a commercial leak detector by reducing the pumping speed at the inlet of the rotary pump, thus increasing its sensitivity by one order of magnitude. The modified detector was used to measure the leak rate of the permeation of He through the glass walls of a photomultiplier. Further improvements made to decrease the minimum detectable signal were limited by the high ultimate pressure in the spectrometer tube

Assessment of the ion-trap mass spectrometer for routine qualitative and quantitative analysis of drugs of abuse extracted from urine.

Science.gov (United States)

Vorce, S P; Sklerov, J H; Kalasinsky, K S

2000-10-01

The ion-trap mass spectrometer (MS) has been available as a detector for gas chromatography (GC) for nearly two decades. However, it still occupies a minor role in forensic toxicology drug-testing laboratories. Quadrupole MS instruments make up the majority of GC detectors used in drug confirmation. This work addresses the use of these two MS detectors, comparing the ion ratio precision and quantitative accuracy for the analysis of different classes of abused drugs extracted from urine. Urine specimens were prepared at five concentrations each for amphetamine (AMP), methamphetamine (METH), benzoylecgonine (BZE), delta9-carboxy-tetrahydrocannabinol (delta9-THCCOOH), phencyclidine (PCP), morphine (MOR), codeine (COD), and 6-acetylmorphine (6-AM). Concentration ranges for AMP, METH, BZE, delta9-THCCOOH, PCP, MOR, COD, and 6-AM were 50-2500, 50-5000, 15-800, 1.5-65, 1-250, 500-32000, 250-21000, and 1.5-118 ng/mL, respectively. Sample extracts were injected into a GC-quadrupole MS operating in selected ion monitoring (SIM) mode and a GC-ion-trap MS operating in either selected ion storage (SIS) or full scan (FS) mode. Precision was assessed by the evaluation of five ion ratios for n = 15 injections at each concentration using a single-point calibration. Precision measurements for SIM ion ratios provided coefficients of variation (CV) between 2.6 and 9.8% for all drugs. By comparison, the SIS and FS data yielded CV ranges of 4.0-12.8% and 4.0-11.2%, respectively. The total ion ratio failure rates were 0.2% (SIM), 0.7% (SIS), and 1.2% (FS) for the eight drugs analyzed. Overall, the SIS mode produced stable, comparable mean ratios over the concentration ranges examined, but had greater variance within batch runs. Examination of postmortem and quality-control samples produced forensically accurate quantitation by SIS when compared to SIM. Furthermore, sensitivity of FS was equivalent to SIM for all compounds examined except for 6-AM.

Determination of vanillin, ethyl vanillin, and coumarin in infant formula by liquid chromatography-quadrupole linear ion trap mass spectrometry.

Science.gov (United States)

Shen, Yan; Han, Chao; Liu, Bin; Lin, Zhengfeng; Zhou, Xiujin; Wang, Chengjun; Zhu, Zhenou

2014-02-01

A simple, precise, accurate, and validated liquid chromatography-quadrupole linear ion trap mass spectrometry method was developed for the determination of vanillin, ethyl vanillin, and coumarin in infant formula samples. Following ultrasonic extraction with methanol/water (1:1, vol/vol), and clean-up on an HLB solid-phase extraction cartridge (Waters Corp., Milford, MA), samples were separated on a Waters XSelect HSS T3 column (150 × 2.1-mm i.d., 5-μm film thickness; Waters Corp.), with 0.1% formic acid solution-acetonitrile as mobile phase at a flow rate of 0.25 mL/min. Quantification of the target was performed by the internal standard approach, using isotopically labeled compounds for each chemical group, to correct matrix effects. Data acquisition was carried out in multiple reaction monitoring transitions mode, monitoring 2 multiple reaction monitoring transitions to ensure an accurate identification of target compounds in the samples. Additional identification and confirmation of target compounds were performed using the enhanced product ion modus of the linear ion trap. The novel liquid chromatography-quadrupole linear ion trap mass spectrometry platform offers the best sensitivity and specificity for characterization and quantitative determination of vanillin, ethyl vanillin, and coumarin in infant formula and fulfills the quality criteria for routine laboratory application. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The distributed control system of Shanghai mini-cyclotron accelerator mass spectrometer (SMCAMS)

International Nuclear Information System (INIS)

Shao Yuhe

2001-01-01

It is mainly introduced the composition, structure, hardware and software designing, function, and the method of communication between the host computer and the ADAM modules of the distributed control system on Shanghai Mini-cyclotron Accelerator Mass Spectrometer (SMCAMS). Some detail problems such as controlling the devices staying on high voltage by ADAM-4541 (RS-485 to Fiber Optic Convertor) and optical fiber are also introduced

Use of the Isomass 54E thermal ionisation mass spectrometer at AEE Winfrith

International Nuclear Information System (INIS)

Knight, A.P.

1982-03-01

A Vacuum Generators Isomass 54E mass spectrometer is used to carry out isotopic analyses. The capabilities of the instrument and its method of operation are outlined, and the technique used for isotopic analysis of uranium is described in detail, with results of tests on NBS standard specimens and Zebra fuel element pellets. (U.K.)

Development of an advanced spacecraft tandem mass spectrometer

Science.gov (United States)

Drew, Russell C.

1992-03-01

The purpose of this research was to apply current advanced technology in electronics and materials to the development of a miniaturized Tandem Mass Spectrometer that would have the potential for future development into a package suitable for spacecraft use. The mass spectrometer to be used as a basis for the tandem instrument would be a magnetic sector instrument, of Nier-Johnson configuration, as used on the Viking Mars Lander mission. This instrument configuration would then be matched with a suitable second stage MS to provide the benefits of tandem MS operation for rapid identification of unknown organic compounds. This tandem instrument is configured with a newly designed GC system to aid in separation of complex mixtures prior to MS analysis. A number of important results were achieved in the course of this project. Among them were the development of a miniaturized GC subsystem, with a unique desorber-injector, fully temperature feedback controlled oven with powered cooling for rapid reset to ambient conditions, a unique combination inlet system to the MS that provides for both membrane sampling and direct capillary column sample transfer, a compact and ruggedized alignment configuration for the MS, an improved ion source design for increased sensitivity, and a simple, rugged tandem MS configuration that is particularly adaptable to spacecraft use because of its low power and low vacuum pumping requirements. The potential applications of this research include use in manned spacecraft like the space station as a real-time detection and warning device for the presence of potentially harmful trace contaminants of the spacecraft atmosphere, use as an analytical device for evaluating samples collected on the Moon or a planetary surface, or even use in connection with monitoring potentially hazardous conditions that may exist in terrestrial locations such as launch pads, environmental test chambers or other sensitive areas. Commercial development of the technology

Following the Ions through a Mass Spectrometer with Atmospheric Pressure Interface: Simulation of Complete Ion Trajectories from Ion Source to Mass Analyzer.

Science.gov (United States)

Zhou, Xiaoyu; Ouyang, Zheng

2016-07-19

Ion trajectory simulation is an important and useful tool in instrumentation development for mass spectrometry. Accurate simulation of the ion motion through the mass spectrometer with atmospheric pressure ionization source has been extremely challenging, due to the complexity in gas hydrodynamic flow field across a wide pressure range as well as the computational burden. In this study, we developed a method of generating the gas flow field for an entire mass spectrometer with an atmospheric pressure interface. In combination with the electric force, for the first time simulation of ion trajectories from an atmospheric pressure ion source to a mass analyzer in vacuum has been enabled. A stage-by-stage ion repopulation method has also been implemented for the simulation, which helped to avoid an intolerable computational burden for simulations at high pressure regions while it allowed statistically meaningful results obtained for the mass analyzer. It has been demonstrated to be suitable to identify a joint point for combining the high and low pressure fields solved individually. Experimental characterization has also been done to validate the new method for simulation. Good agreement was obtained between simulated and experimental results for ion transfer though an atmospheric pressure interface with a curtain gas.

Controllable isotope fractionation with thermal ionisation mass-spectrometers

International Nuclear Information System (INIS)

Hebeda, E.H.

1980-01-01

Isotopic ratios measured with thermal ionisation mass-spectrometers are biased by fractionation effects. A sample must therefore be analyzed according to the same procedures as applied for the analysis of the standard reference material. A comparison of the behaviour of the sample with that of the standard can then be used as a criterion whether the analytical results are acceptable or not. In this way it is possible to obtain reproducibilities similar to those for elements acceptable or not. In this way it is possible to obtain reproducibilities similar to those for elements where the fractionation can be determined by an internal standard. This procedure of controlled fractionation is demonstrated by means of the 88 Sr/ 86 Sr ratios measured on geological samples and the SRM 987 standard. (orig.)

A large-aperture, low-resolution quadrupole separator for producing deposited cluster materials

CERN Document Server

Denby, P M

2000-01-01

A wide-aperture, low-resolution quadrupole separator for metal clusters is described. Its performance has been evaluated by numerical calculations of the trajectories of clusters. Operating in the frequency range from 5 to 100 KHz allows one to separate clusters in the mass range from 30000 to 300000 AMU and by suitable choice of the AC and DC voltages one can obtain a resolution of 0.15. At this resolution the transmission of clusters from a source is 100% over the selected mass range. By biasing the quadrupole it has been possible to obtain a very sharp cut-off between the transmitted clusters and those outside the selected range. Trajectory calculation for clusters deposited onto a biased 2 cm diameter substrate show that it is possible to keep the deposition energy below 25 eV for 90% of the clusters when the quadrupole is itself biased.

A large-aperture, low-resolution quadrupole separator for producing deposited cluster materials

Energy Technology Data Exchange (ETDEWEB)

Denby, P.M.; Eastham, D.A. E-mail: d.a.eastham@dl.ac.uk

2000-03-01

A wide-aperture, low-resolution quadrupole separator for metal clusters is described. Its performance has been evaluated by numerical calculations of the trajectories of clusters. Operating in the frequency range from 5 to 100 KHz allows one to separate clusters in the mass range from 30000 to 300000 AMU and by suitable choice of the AC and DC voltages one can obtain a resolution of 0.15. At this resolution the transmission of clusters from a source is 100% over the selected mass range. By biasing the quadrupole it has been possible to obtain a very sharp cut-off between the transmitted clusters and those outside the selected range. Trajectory calculation for clusters deposited onto a biased 2 cm diameter substrate show that it is possible to keep the deposition energy below 25 eV for 90% of the clusters when the quadrupole is itself biased.

A large-aperture, low-resolution quadrupole separator for producing deposited cluster materials

International Nuclear Information System (INIS)

Denby, P.M.; Eastham, D.A.

2000-01-01

A wide-aperture, low-resolution quadrupole separator for metal clusters is described. Its performance has been evaluated by numerical calculations of the trajectories of clusters. Operating in the frequency range from 5 to 100 KHz allows one to separate clusters in the mass range from 30000 to 300000 AMU and by suitable choice of the AC and DC voltages one can obtain a resolution of 0.15. At this resolution the transmission of clusters from a source is 100% over the selected mass range. By biasing the quadrupole it has been possible to obtain a very sharp cut-off between the transmitted clusters and those outside the selected range. Trajectory calculation for clusters deposited onto a biased 2 cm diameter substrate show that it is possible to keep the deposition energy below 25 eV for 90% of the clusters when the quadrupole is itself biased

Overview of the Axial Field Spectrometer in the ISR tunnel

CERN Multimedia

1980-01-01

A view of the Axial Field Spectrometer – the last large experiment at the ISR. The horizontal top and vertical outer arrays of the uranium-scintillator hadron calorimeter are clear to be seen, with the blue cylindrical pole piece of the magnet just visible. The pipes that are visible in front of the pole piece are cryogenic feed pipes for the superconducting low-beta quadrupoles.

Environmental Technology Verification Report. Field Portable Gas Chromatograph/Mass Spectrometer. Viking Instruments Corporation SpectraTrak (Trademark) 672

National Research Council Canada - National Science Library

Enfield, Wayne

1997-01-01

.... This self-contained, field transportable system, whose design has been adapted from laboratory technology, uses a contained, chromatographic column and accompanying mass spectrometer to provide...

Tandem Mass Spectrometry on a Miniaturized Laser Desorption Time-of-Flight Mass Spectrometer

Science.gov (United States)

Li, Xiang; Cornish, Timothy; Getty, Stephanie A.; Brinckerhoff, William B.

2016-01-01

Tandem mass spectrometry (MSMS) is a powerful and widely-used technique for identifying the molecular structure of organic constituents of a complex sample. Application of MSMS to the study of unknown planetary samples on a remote space mission would contribute to our understanding of the origin, evolution, and distribution of extraterrestrial organics in our solar system. Here we report on the realization of MSMS on a miniaturized laser desorption time-of-flight mass spectrometer (LD-TOF-MS), which is one of the most promising instrument types for future planetary missions. This achievement relies on two critical components: a curved-field reflectron and a pulsed-pin ion gate. These enable use of the complementary post-source decay (PSD) and laser-assisted collision induced dissociation (L-CID) MSMS methods on diverse measurement targets with only modest investment in instrument resources such as volume and weight. MSMS spectra of selected molecular targets in various organic standards exhibit excellent agreement when compared with results from a commercial, laboratory-scale TOF instrument, demonstrating the potential of this powerful technique in space and planetary environments.

Mass spectrometric analysis of helium in stainless steel

International Nuclear Information System (INIS)

Isagawa, Hiroto; Wada, Yukio; Asakura, Yoshiro; Tsuji, Nobuo; Sato, Hitoshi; Tsutsumi, Kenichi

1974-01-01

Vacuum fusion mass-spectrometry was adopted for the analysis of helium in stainless steel. Samples were heated in a vacuum crucible, and helium in the samples was extracted and collected into a reservoir tank. The gas was then introduced through an orifice into a mass spectrometer, where the amount of helium was determined. The maspeq 070 quadrupole type mass spectrometer made by Shimazu Seisakusho, Ltd. was used. The resolving power was 150, and the mass range of the apparatus was 0-150. The determination limit of helium was about 2 x 10 -3 μg when standard helium gas was analyzed, and was about 10 -2 μg when the helium in stainless steel was analyzed. The relative standard deviation of helium intensity in repetitive measurement was about 2% in the amount of helium of 0.05 μg. Helium was injected into stainless steel by means of alpha particle irradiation with a cyclotron. The amount of helium in stainless steel was then determined. The energy of alpha particles was 34 MeV, and the beam area was 10 mm x 10 mm. The experimental data were higher than the expected value in one case, and were lower in the other case. This difference was attributable to the fluctuation of alpha particle beam, misplacement of sample plates, and unevenness of the alpha beam. (Fukutomi, T.)

Method for selective detection of explosives in mass spectrometer or ion mobility spectrometer at parts-per-quadrillion level

Science.gov (United States)

Ewing, Robert G.; Atkinson, David A.; Clowers, Brian H.

2015-09-01

A method for selective detection of volatile and non-volatile explosives in a mass spectrometer or ion mobility spectrometer at a parts-per-quadrillion level without preconcentration is disclosed. The method comprises the steps of ionizing a carrier gas with an ionization source to form reactant ions or reactant adduct ions comprising nitrate ions (NO.sub.3.sup.-); selectively reacting the reactant ions or reactant adduct ions with at least one volatile or non-volatile explosive analyte at a carrier gas pressure of at least about 100 Ton in a reaction region disposed between the ionization source and an ion detector, the reaction region having a length which provides a residence time (tr) for reactant ions therein of at least about 0.10 seconds, wherein the selective reaction yields product ions comprising reactant ions or reactant adduct ions that are selectively bound to the at least one explosive analyte when present therein; and detecting product ions with the ion detector to determine presence or absence of the at least one explosive analyte.

Effect of heating strategies on whey protein denaturation--Revisited by liquid chromatography quadrupole time-of-flight mass spectrometry.

Science.gov (United States)

Akkerman, M; Rauh, V M; Christensen, M; Johansen, L B; Hammershøj, M; Larsen, L B

2016-01-01

Previous standards in the area of effect of heat treatment processes on milk protein denaturation were based primarily on laboratory-scale analysis and determination of denaturation degrees by, for example, electrophoresis. In this study, whey protein denaturation was revisited by pilot-scale heating strategies and liquid chromatography quadrupole time-of-flight mass spectrometer (LC/MC Q-TOF) analysis. Skim milk was heat treated by the use of 3 heating strategies, namely plate heat exchanger (PHE), tubular heat exchanger (THE), and direct steam injection (DSI), under various heating temperatures (T) and holding times. The effect of heating strategy on the degree of denaturation of β-lactoglobulin and α-lactalbumin was determined using LC/MC Q-TOF of pH 4.5-soluble whey proteins. Furthermore, effect of heating strategy on the rennet-induced coagulation properties was studied by oscillatory rheometry. In addition, rennet-induced coagulation of heat-treated micellar casein concentrate subjected to PHE was studied. For skim milk, the whey protein denaturation increased significantly as T and holding time increased, regardless of heating method. High denaturation degrees were obtained for T >100°C using PHE and THE, whereas DSI resulted in significantly lower denaturation degrees, compared with PHE and THE. Rennet coagulation properties were impaired by increased T and holding time regardless of heating method, although DSI resulted in less impairment compared with PHE and THE. No significant difference was found between THE and PHE for effect on rennet coagulation time, whereas the curd firming rate was significantly larger for THE compared with PHE. Micellar casein concentrate possessed improved rennet coagulation properties compared with skim milk receiving equal heat treatment. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Eight piece quadrupole magnet, method for aligning quadrupole magent pole tips

Science.gov (United States)

Jaski, Mark S.; Liu, Jie; Donnelly, Aric T.; Downey, Joshua S.; Nudell, Jeremy J.; Jain, Animesh

2018-01-30

The invention provides an alternative to the standard 2-piece or 4-piece quadrupole. For example, an 8-piece and a 10-piece quadrupole are provided whereby the tips of each pole may be adjustable. Also provided is a method for producing a quadrupole using standard machining techniques but which results in a final tolerance accuracy of the resulting construct which is better than that obtained using standard machining techniques.

Peter J Derrick and the Grand Scale 'Magnificent Mass Machine' mass spectrometer at Warwick.

Science.gov (United States)

Colburn, A W; Derrick, Peter J; Bowen, Richard D

2017-12-01

The value of the Grand Scale 'Magnificent Mass Machine' mass spectrometer in investigating the reactivity of ions in the gas phase is illustrated by a brief analysis of previously unpublished work on metastable ionised n-pentyl methyl ether, which loses predominantly methanol and an ethyl radical, with very minor contributions for elimination of ethane and water. Expulsion of an ethyl radical is interpreted in terms of isomerisation to ionised 3-pentyl methyl ether, via distonic ions and, possibly, an ion-neutral complex comprising ionised ethylcyclopropane and methanol. This explanation is consistent with the closely similar behaviour of the labelled analogues, C 3 H 7 CH 2 CD 2 OCH 3 +. and C 3 H 7 CD 2 CH 2 OCH 3 +. , and is supported by the greater kinetic energy release associated with loss of ethane from ionised n-propyl methyl ether compared to that starting from directly generated ionised 3-pentyl methyl ether.

Engineering Sensitivity Improvement of Helium Mass Spectrometer Leak Detection System by Means Global Hard Vacuum Test

International Nuclear Information System (INIS)

Sigit Asmara Santa

2006-01-01

The engineering sensitivity improvement of Helium mass spectrometer leak detection using global hard vacuum test configuration has been done. The purpose of this work is to enhance the sensitivity of the current leak detection of pressurized method (sniffer method) with the sensitivity of 10 -3 ∼ 10 -5 std cm 3 /s, to the global hard vacuum test configuration method which can be achieved of up to 10 -8 std cm 3 /s. The goal of this research and development is to obtain a Helium leak test configuration which is suitable and can be used as routine bases in the quality control tests of FPM capsule and AgInCd safety control rod products. The result is an additional instrumented vacuum tube connected with conventional Helium mass spectrometer. The pressure and temperature of the test object during the leak measurement are simulated by means of a 4.1 kW capacity heater and Helium injection to test object, respectively. The addition of auxiliary mechanical vacuum pump of 2.4 l/s pumping speed which is directly connected to the vacuum tube, will reduce 86 % of evacuation time. The reduction of the measured sensitivity due to the auxiliary mechanical vacuum pump can be overcome by shutting off the pump soon after Helium mass spectrometer reaches its operating pressure condition. (author)

Process for detecting leak faults using a helium mass spectrometer

International Nuclear Information System (INIS)

Divet, Claude; Morin, Claude.

1977-01-01

The description is given of a process for detecting very small leak faults putting into communication the outer and inner sides of the wall of a containment, one of these wall sides being in contact with gaseous helium under a pressure of around one torr, the other side being one of the limits of a space pumped down to a residual gas pressure under 10 -3 torr. This space is in communication with the measuring cell of a helium mass spectrometer. This process may be applied to the detection of faults in metal claddings of the fuel rods used in nuclear reactors [fr

Compositional characterisation of rare earth magnet materials by glow discharge quadrupole mass spectrometry

International Nuclear Information System (INIS)

Reddy, M.A.; Shekhar, R.; Kumar, Sunil Jai

2014-01-01

In this paper, glow discharge quadrupole mass spectrometric (GD-QMS) studies on Sm-Pr-Co compound magnetic materials are reported. The composition of these magnetic materials produced from different manufacturing routes (imported, indigenous) was determined. The results are compared with the results obtained by an alternative analytic technique, inductively coupled plasma atomic emission spectrometry (ICP-AES), after complete dissolution of the material in the appropriate acids. For perfectly homogeneous material both the wet chemical method and direct solid analysis method should give the same result. A close examination of both the results indicates that for imported materials the values obtained by wet chemical method and direct solid method are in close agreement. This indicates that the imported (solid) material is highly homogeneous. For indigenous materials, it shows a large difference in the values of Co and Sm. This reveals that the solid material prepared is not as homogenous as the imported materials

Mass spectrometer calibration of Cosmic Dust Analyzer

Science.gov (United States)

Ahrens, Thomas J.; Gupta, Satish C.; Jyoti, G.; Beauchamp, J. L.

2003-02-01

The time-of-flight (TOF) mass spectrometer (MS) of the Cosmic Dust Analyzer (CDA) instrument aboard the Cassini spacecraft is expected to be placed in orbit about Saturn to sample submicrometer-diameter ring particles and impact ejecta from Saturn's satellites. The CDA measures a mass spectrum of each particle that impacts the chemical analyzer sector of the instrument. Particles impact a Rh target plate at velocities of 1-100 km/s and produce some 10-8 to 10-5 times the particle mass of positive valence, single-charged ions. These are analyzed via a TOF MS. Initial tests employed a pulsed N2 laser acting on samples of kamacite, pyrrhotite, serpentine, olivine, and Murchison meteorite induced bursts of ions which were detected with a microchannel plate and a charge sensitive amplifier (CSA). Pulses from the N2 laser (1011 W/cm2) are assumed to simulate particle impact. Using aluminum alloy as a test sample, each pulse produces a charge of ~4.6 pC (mostly Al+1), whereas irradiation of a stainless steel target produces a ~2.8 pC (Fe+1) charge. Thus the present system yields ~10-5% of the laser energy in resulting ions. A CSA signal indicates that at the position of the microchannel plate, the ion detector geometry is such that some 5% of the laser-induced ions are collected in the CDA geometry. Employing a multichannel plate detector in this MS yields for Al-Mg-Cu alloy and kamacite targets well-defined peaks at 24 (Mg+1), 27(Al+1), and 64 (Cu+1) and 56 (Fe+1), 58 (Ni+1), and 60 (Ni+1) dalton, respectively.

ChiMS: Open-source instrument control software platform on LabVIEW for imaging/depth profiling mass spectrometers.

Science.gov (United States)

Cui, Yang; Hanley, Luke

2015-06-01

ChiMS is an open-source data acquisition and control software program written within LabVIEW for high speed imaging and depth profiling mass spectrometers. ChiMS can also transfer large datasets from a digitizer to computer memory at high repetition rate, save data to hard disk at high throughput, and perform high speed data processing. The data acquisition mode generally simulates a digital oscilloscope, but with peripheral devices integrated for control as well as advanced data sorting and processing capabilities. Customized user-designed experiments can be easily written based on several included templates. ChiMS is additionally well suited to non-laser based mass spectrometers imaging and various other experiments in laser physics, physical chemistry, and surface science.

Helium Mass Spectrometer Leak Detection: A Method to Quantify Total Measurement Uncertainty

Science.gov (United States)

Mather, Janice L.; Taylor, Shawn C.

2015-01-01

In applications where leak rates of components or systems are evaluated against a leak rate requirement, the uncertainty of the measured leak rate must be included in the reported result. However, in the helium mass spectrometer leak detection method, the sensitivity, or resolution, of the instrument is often the only component of the total measurement uncertainty noted when reporting results. To address this shortfall, a measurement uncertainty analysis method was developed that includes the leak detector unit's resolution, repeatability, hysteresis, and drift, along with the uncertainty associated with the calibration standard. In a step-wise process, the method identifies the bias and precision components of the calibration standard, the measurement correction factor (K-factor), and the leak detector unit. Together these individual contributions to error are combined and the total measurement uncertainty is determined using the root-sum-square method. It was found that the precision component contributes more to the total uncertainty than the bias component, but the bias component is not insignificant. For helium mass spectrometer leak rate tests where unit sensitivity alone is not enough, a thorough evaluation of the measurement uncertainty such as the one presented herein should be performed and reported along with the leak rate value.

Ion Mobility Spectrometer / Mass Spectrometer (IMS-MS)

Energy Technology Data Exchange (ETDEWEB)

Hunka, Deborah E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Austin, Daniel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2005-10-01

The use of Ion Mobility Spectrometry (IMS)in the Detection of Contraband Sandia researchers use ion mobility spectrometers for trace chemical detection and analysis in a variety of projects and applications. Products developed in recent years based on IMS-technology include explosives detection personnel portals, the Material Area Access (MAA) checkpoint of the future, an explosives detection vehicle portal, hand-held detection systems such as the Hound and Hound II (all 6400), micro-IMS sensors (1700), ordnance detection (2500), and Fourier Transform IMS technology (8700). The emphasis to date has been on explosives detection, but the detection of chemical agents has also been pursued (8100 and 6400).

Influence of the coupling between an atmospheric pressure ion mobility spectrometer and the low pressure ion inlet of a mass spectrometer on the mobility measurement

Directory of Open Access Journals (Sweden)

Gunzer Frank

2016-01-01

Full Text Available Ion mobility spectrometers (IMS are versatile gas analyzers. Due to their small size and robustness, combined with a very high sensitivity, they are often used in gas sensing applications such as environmental monitoring. In order to improve the selectivity, they are typically combined with a mass spectrometer (MS. Since IMS works at atmospheric pressure, and MS works at vacuum, a special interface reducing the pressure over normally two stages has to be used. In this paper the influence of this coupling of different pressure areas on the IMS signal will be analyzed with help of finite elements method simulations.

THOR Ion Mass Spectrometer instrument - IMS

Science.gov (United States)

Retinò, Alessandro; Kucharek, Harald; Saito, Yoshifumi; Fraenz, Markus; Verdeil, Christophe; Leblanc, Frederic; Techer, Jean-Denis; Jeandet, Alexis; Macri, John; Gaidos, John; Granoff, Mark; Yokota, Shoichiro; Fontaine, Dominique; Berthomier, Matthieu; Delcourt, Dominique; Kistler, Lynn; Galvin, Antoniette; Kasahara, Satoshi; Kronberg, Elena

2016-04-01

Turbulence Heating ObserveR (THOR) is the first mission ever flown in space dedicated to plasma turbulence. Specifically, THOR will study how turbulent fluctuations at kinetic scales heat and accelerate particles in different turbulent environments within the near-Earth space. To achieve this goal, THOR payload is being designed to measure electromagnetic fields and particle distribution functions with unprecedented resolution and accuracy. Here we present the Ion Mass Spectrometer (IMS) instrument that will measure the full three-dimensional distribution functions of near-Earth main ion species (H+, He+, He++ and O+) at high time resolution (~ 150 ms for H+ , ~ 300 ms for He++) with energy resolution down to ~ 10% in the range 10 eV/q to 30 keV/q and angular resolution ~ 10°. Such high time resolution is achieved by mounting multiple sensors around the spacecraft body, in similar fashion to the MMS/FPI instrument. Each sensor combines a top-hat electrostatic analyzer with deflectors at the entrance together with a time-of-flight section to perform mass selection. IMS electronics includes a fast sweeping high voltage board that is required to make measurements at high cadence. Ion detection includes Micro Channel Plates (MCP) combined with Application-Specific Integrated Circuits (ASICs) for charge amplification, discrimination and time-to-digital conversion (TDC). IMS is being designed to address many of THOR science requirements, in particular ion heating and acceleration by turbulent fluctuations in foreshock, shock and magnetosheath regions. The IMS instrument is being designed and will be built by an international consortium of scientific institutes with main hardware contributions from France, USA, Japan and Germany.

Some conceptual designs for a LASSY spectrometer magnet

International Nuclear Information System (INIS)

Green, M.A.

1995-09-01

The LASSY spectrometer is a gas filled spectrometer (hydrogen or helium at a pressure of about 1 torr). The design bending power for the primary bending magnet for the spectrometer will have an induction bend radius product of 2.5 tesla-meters. In order to increase the acceptance of the spectrometer, the bending magnet system must be located close to the target where the desired nuclei are created. The spectrometer magnet system must consist of both bending and focusing elements so that the wide acceptance of particles can be brought to a focus at the analysis point that is down stream from the last magnet element. In order improve the spectrometer resolution and to catch the shortest lived nuclei, the length of the magnet system must be as short as possible. The length for the LASSY spectrometer magnet system from the target to the analysis point has been set at 2.5 meters or less. To improve the resolution of the spectrometer, the bending angle for bending magnet system must be increased to close to 180 degrees. In order to achieve a large bending angle and a short magnet system length, the bending induction must be above 3 tesla and the focusing elements must be combined with the bending elements. As a result, a LASSY spectrometer will have bending magnet with a bending angle from 140 to 170 degrees. This magnet win be combined with one or more focusing magnets (a straight dipole in some places and a combined function dipole in other places). The result is a single superconducting bending magnet with one or more quadrupoles incorporated within the large angle bending magnet

A small sized time-of-flight mass spectrometer for simultaneous measurement of neutral and ionic species effusing from plasma, 1

International Nuclear Information System (INIS)

Horiuchi, Yukihiko

1986-01-01

A principle for simultaneous and real time measurement of neutral and ionic species effusing from plasma by using a time-of-flight mass spectrometer is proposed. A simple, small sized time-of-flight mass spectrometer combined with a dc glow discharge tube and an ion sampling electrode system for the simultaneous measurement on the basis of the proposed plinciple, has been constructed and tested. Details of the experimental setup including the geometry and the electronic hardware are described. It is shown that mass spectra of neutrals and ions from the positive column of the argon dc glow discharge are successfully observed on a single oscilloscope display. (author)

PDS4 vs PDS3 - A Comparison of PDS Data for Two Mars Rovers - Existing Mars Curiosity Mission Mass Spectrometer (SAM) PDS3 Data vs Future ExoMars Rover Mass Spectrometer (MOMA) PDS4 Data

Science.gov (United States)

Lyness, E.; Franz, H. B.; Prats, B.

2017-12-01

The Sample Analysis at Mars (SAM) instrument is a suite of instruments on Mars aboard the Mars Science Laboratory rover. Centered on a mass spectrometer, SAM delivers its data to the PDS Atmosphere's node in PDS3 format. Over five years on Mars the process of operating SAM has evolved and extended significantly from the plan in place at the time the PDS3 delivery specification was written. For instance, SAM commonly receives double or even triple sample aliquots from the rover's drill. SAM also stores samples in spare cups for long periods of time for future analysis. These unanticipated operational changes mean that the PDS data deliveries are absent some valuable metadata without which the data can be confusing. The Mars Organic Molecule Analyzer (MOMA) instrument is another suite of instruments centered on a mass spectrometer bound for Mars. MOMA is part of the European ExoMars rover mission schedule to arrive on Mars in 2021. While SAM and MOMA differ in some important scientific ways - MOMA uses an linear ion trap compared to the SAM quadropole mass spectrometer and MOMA has a laser desorption experiment that SAM lacks - the data content from the PDS point of view is comparable. Both instruments produce data containing mass spectra acquired from solid samples collected on the surface of Mars. The MOMA PDS delivery will make use of PDS4 improvements to provide a metadata context to the data. The MOMA PDS4 specification makes few assumptions of the operational processes. Instead it provides a means for the MOMA operators to provide the important contextual metadata that was unanticipated during specification development. Further, the software tools being developed for instrument operators will provide a means for the operators to add this crucial metadata at the time it is best know - during operations.

Single-stage accelerator mass spectrometer radiocarbon-interference identification and positive-ionisation characterisation

Energy Technology Data Exchange (ETDEWEB)

Wilcken, K.M., E-mail: klaus.wilcken@ansto.gov.au [Scottish Universities Environmental Research Centre, Scottish Enterprise Technology Park, East Kilbride G75 0QF (United Kingdom); Freeman, S.P.H.T.; Xu, S.; Dougans, A. [Scottish Universities Environmental Research Centre, Scottish Enterprise Technology Park, East Kilbride G75 0QF (United Kingdom)

2013-01-15

A single-stage accelerator mass spectrometer (SSAMS) is a good alternative to conventional spectrometers based on tandem electrostatic acceleration for radiocarbon measurement and permits experimentation with both negative and positive carbon ions. However, such {sup 14}C AMS of either polarity ions is limited by an interference. In the case of anion acceleration we have newly determined this to be summed {sup 13}C and {sup 16}O by improvising an additional Wien filter on our SSAMS deck. Also, {sup 14}C AMS might be improved by removing its dependency on negative-ionisation in a sputter ion source. This requires negative-ionisation of sample atoms elsewhere to suppress the {sup 14}N interference, which we accomplish by transmitting initially positive ions through a thin membrane. The ionisation dependence on ion-energy is found to be consistent with previous experimentation with vapours and thicker foils.

Superconducting magnetic quadrupole

Energy Technology Data Exchange (ETDEWEB)

Kim, J.W.; Shepard, K.W.; Nolen, J.A.

1995-08-01

A design was developed for a 350 T/m, 2.6-cm clear aperture superconducting quadrupole focussing element for use in a very low q/m superconducting linac as discussed below. The quadrupole incorporates holmium pole tips, and a rectangular-section winding using standard commercially-available Nb-Ti wire. The magnet was modeled numerically using both 2D and 3D codes, as a basis for numerical ray tracing using the quadrupole as a linac element. Components for a prototype singlet are being procured during FY 1995.

Improved detection limits for electrospray ionization on a magnetic sector mass spectrometer by using an array detector.

Science.gov (United States)

Cody, R B; Tamura, J; Finch, J W; Musselman, B D

1994-03-01

Array detection was compared with point detection for solutions of hen egg-white lysozyme, equine myoglobin, and ubiquitin analyzed by electrospray ionization with a magnetic sector mass spectrometer. The detection limits for samples analyzed by using the array detector system were at least 10 times lower than could be achieved by using a point detector on the same mass spectrometer. The minimum detectable quantity of protein corresponded to a signal-to-background ratio of approximately 2∶1 for a 500 amol/μL solution of hen egg-white lysozyme. However, the ultimate practical sample concentrations appeared to be in the 10-100 fmol/μL range for the analysis of dilute solutions of relatively pure proteins or simple mixtures.

Magnetic field measurements of LHC inner triplet quadrupoles fabricated at Fermilab

International Nuclear Information System (INIS)

Velev, G.V.; Bossert, R.; Carcagno, R.; DiMarco, J.; Feher, S.; Kashikhin, V.V.; Kerby, J.; Lamm, M.; Orris, D.; Schlabach, P.; Strait, J.

2006-01-01

Fermilab, as part of the US-LHC Accelerator Project, is producing superconducting low-beta quadrupole magnets for the Large Hadron Collider (LHC). These 5.5 m long magnets are designed to operate in superfluid helium at 1.9 K with a nominal gradient of 205 T/m in the 70 mm bore. Two quadrupoles separated by a dipole orbit corrector in a single cryogenic assembly comprise the Q2 optical elements of the final focus triplets in the LHC interaction regions. The field quality of the quadrupoles is measured at room temperature during construction of the cold masses as well as during cold testing of the cryogenic assembly. We summarize data from the series measurements of the magnets and discuss various topics of interest

Magnetic field measurements of LHC inner triplet quadrupoles fabricated at Fermilab

Energy Technology Data Exchange (ETDEWEB)

Velev, G.V.; Bossert, R.; Carcagno, R.; DiMarco, J.; Feher, S.; Kashikhin, V.V.; Kerby, J.; Lamm, M.; Orris, D.; Schlabach, P.; Strait, J.; /Fermilab

2006-08-01

Fermilab, as part of the US-LHC Accelerator Project, is producing superconducting low-beta quadrupole magnets for the Large Hadron Collider (LHC). These 5.5 m long magnets are designed to operate in superfluid helium at 1.9 K with a nominal gradient of 205 T/m in the 70 mm bore. Two quadrupoles separated by a dipole orbit corrector in a single cryogenic assembly comprise the Q2 optical elements of the final focus triplets in the LHC interaction regions. The field quality of the quadrupoles is measured at room temperature during construction of the cold masses as well as during cold testing of the cryogenic assembly. We summarize data from the series measurements of the magnets and discuss various topics of interest.

Influence of Coulomb effects on the resolving power of multireflection mass-spectrometer systems

International Nuclear Information System (INIS)

Skoblin, M G; Kopaev, I A; Monastyrskiy, M A; Alimpiev, S S; Greenfield, D E; Makarov, A A

2015-01-01

General theoretical approaches to the modelling of Coulomb effects in short ion bunches, developed previously by the authors, are applied in this paper to the calculation of multireflection mass-spectrometer systems. A separate module of the MASIM 3D applied software package is designed. An adaptive computational procedure for calculating the 'mirror potential' induced by an ion bunch on the surface of field-forming electrodes is proposed. The dynamics of ion bunches in a time-of-flight reflectron-type mass analyser is calculated and the limitations on the resolving power, caused by resonant Coulomb effects of self-bunching and coalescence in the groups of particles with close masses, are revealed on the basis of numerical experiments. (laser applications and other topics in quantum electronics)

Simultaneous determination of niacin and pyridoxine at trace levels by using diode array high-performance liquid chromatography and liquid chromatography with quadrupole time-of-flight tandem mass spectrometry.

Science.gov (United States)

Sel, Sabriye; Öztürk Er, Elif; Bakırdere, Sezgin

2017-12-01

A highly sensitive and simple diode-array high-performance liquid chromatography and liquid chromatography with quadrupole time-of-flight tandem mass spectrometry method was developed for the simultaneous determination of niacin and pyridoxine in pharmaceutical drugs, tap water, and wastewater samples. To determine the in vivo behavior of niacin and pyridoxine, analytes were subjected to simulated gastric conditions. The calibration plots of the diode-array high-performance liquid chromatography and liquid chromatography with quadrupole time-of-flight tandem mass spectrometry method showed good linearity over a wide concentration range with close to 1.0 correlation coefficients for both analytes. The limit of detection/limit of quantitation values for liquid chromatography quadrupole time-of-flight tandem mass spectrometry analysis were 1.98/6.59 and 1.3/4.4 μg/L for niacin and pyridoxine, respectively, while limit of detection/limit of quantitation values for niacin and pyridoxine in high-performance liquid chromatography analysis were 3.7/12.3 and 5.7/18.9 μg/L, respectively. Recovery studies were also performed to show the applicability of the developed methods, and percentage recovery values were found to be 90-105% in tap water and 94-97% in wastewater for both analytes. The method was also successfully applied for the qualitative and quantitative determination of niacin and pyridoxine in drug samples. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Principles and applications of a research-oriented gas chromatography-mass spectrometry data system

International Nuclear Information System (INIS)

Campana, J.E.; Risby, T.H.; Jurs, P.C.

1979-01-01

A research-oriented gas chromatography-mass spectrometry data system for a quadrupole mass spectrometer has been developed based on a centrally located departmental computer facility. An overview of the hardware and software system is presented, emphasizing the important aspects of on-line computer data acquisition and control and the design philosophy used in the development of the system. The application of the system is demonstrated by the g.c.-m.s. analysis of a mixture of four transition metal β-diketonates (Al, Cr, Rh, and Ru tris-1,1,1-trifluoro-pentane-2,4-dionate). This anaysis involved vacuum gas chromatography with a support-coated open tubular column and detection of the eluent by chemical ionization mass spectrometry. The results demonstrate the data system capabilities and indicate the utility of the combined methodologies. (Auth.)

Measurement of mass and isotopic fission yields for heavy fission products with the LOHENGRIN mass spectrometer

International Nuclear Information System (INIS)

Bail, A.

2009-05-01

In spite of the huge amount of fission yield data available in different libraries, more accurate values are still needed for nuclear energy applications and to improve our understanding of the fission process. Thus measurements of fission yields were performed at the mass spectrometer Lohengrin at the Institut Laue-Langevin in Grenoble, France. The mass separator Lohengrin is situated at the research reactor of the institute and permits the placement of an actinide layer in a high thermal neutron flux. It separates fragments according to their atomic mass, kinetic energy and ionic charge state by the action of magnetic and electric fields. Coupled to a high resolution ionization chamber the experiment was used to investigate the mass and isotopic yields of the light mass region. Almost all fission yields of isotopes from Th to Cf have been measured at Lohengrin with this method. To complete and improve the nuclear data libraries, these measurements have been extended in this work to the heavy mass region for the reactions 235 U(n th ,f), 239 Pu(n th ,f) and 241 Pu(n th ,f). For these higher masses an isotopic separation is no longer possible. So, a new method was undertaken with the reaction 239 Pu(n th ,f) to determine the isotopic yields by spectrometry. These experiments have allowed to reduce considerably the uncertainties. Moreover the ionic charge state and kinetic energy distributions were specifically studied and have shown, among others, nanosecond isomers for some masses. (author)

Nuclear quadrupole-quadrupole interaction in the inelastic scattering of aligned deuterons from deformed nuclei

International Nuclear Information System (INIS)

Clement, H.; Frick, R.; Graw, G.; Schiemenz, P.; Seichert, N.

1983-01-01

The 2 1 + -excitation of deformed nuclei by tensor polarized deuterons provides an alignment of both nuclei and thus a means to study specifically the quadrupole-quadrupole interaction between both nuclei. The tensor analyzing power Asub(xz)(theta) has been measured for the elastic and inelastic scattering on 24 Mg and 28 Si. The coupled channel analysis including a deformed tensor potential reveals a clear signature of the quadrupole-quadrupole part of the nuclear projectile-target interaction. (orig.)

Field-portable Gas Chromatograph Mass Spectrometer (GC-MS) Unit for Semi-volatile Compound Analysis in Groundwater

Science.gov (United States)

2011-09-01

the need for a convective oven, greatly reducing the size and power consumption compared to standard GC systems. These modifications to the...spectrometer. In Harsh Environment Mass Spectrometry (HEMS) Conference; September 2007; Cocoa Beach, FL. Science Applications International Corporation

Direct coupling of a dense (supercritical) gas chromatograph to a mass spectrometer using a supersonic molecular beam interface

International Nuclear Information System (INIS)

Randall, L.G.; Wahrhaftig, A.L.

1981-01-01

A detecting mass spectrometer has been successfully coupled to a dense gas (supercritical fluid) chromatograph to produce an instrument (DGC/MS) that may be an alternative to high performance liquid chromatograph/mass spectrometer instruments (HPLC/MS) and gas chromatograph/mass spectrometer instruments (GC/MS) for analysis of involatile and/or thermally labile compounds. The mobile phase in DGC is a gas held at temperatures above the critical temperature and at pressures sufficient to obtain nearly liquid-like densities. DGC combines advantages of GC and HPLC: rapid separations, moderate operating temperatures, and analysis of involatile compounds. An advantage unique to DGC is the solvent power dependence upon pressure. While several groups have studied DGC, its development has been limited by the lack of a sensitive and selective detector. Hence, work has been directed towards the design and construction of a DGC/MS resulting in a trial instrument capable of chromatographic pressures of at least 300 atm and temperatures from 10 0 to 60 0 C. The DGC/MS coupling has been accomplished by the use of a supersonic molecular beam interface. This application of molecular beam formation appears to be unique in its requirements of a large pressure ratio (approx.10 8 ), low flow rates, and low final pressures. The authors outline characteristics of supersonic jets and molecular beams pertinent to the design of such an instrument. The interface which uses pumping speeds of 2400 and 1200 l/s in the beam forming chambers is described in detail, while the other components: the detecting mass spectrometer, the dense gas supply, and the DGC: are briefly described. Preliminary work with this instrument has established the feasibility of DGC/MS as an analytical technique and further development is recommended

Characterization of a time-of-flight mass spectrometer and its applications in the study of solid surfaces; Charakterisierung eines Flugzeitmassenspektrometers und seine Anwendungen in der Festkoerperoberflaechenuntersuchung

Energy Technology Data Exchange (ETDEWEB)

Mazarov, P.

2006-12-21

The object and the purpose of the present work was to develop, to assemble and to start running a new TOF (time of flight) mass spectrometer for imaging SNMS analytic which is optimized for the analysis of highly molecular secondary ions. The most important purpose was the characterization of the TOF mass spectrometer. The obtained mass spectra of indium, tantalum and silver clusters reflect the excellent properties of the TOF mass spectrometer for the detection of large clusters with good detection efficiency up to masses of 16000 amu. The possibility of the deflection of selected saturated atom and cluster peaks serves for further improvement of the detection efficiency for large molecules. The accessible mass resolution was determined to be of the order of m/{delta}m=1000 in the high mass region. Numerous measurements were carried out to characterize the useful yield of this spectrometer. For a best possible adaptation of the TOF mass spectrometer for the detection of highly molecular particles, a device for post-acceleration of the detected particles by up to 10 keV were inserted directly before the MCP detector. The detection efficiency of positive secondary ions was determined for different post-acceleration voltages for the example of sputtered indium cluster ions. In addition, a new method was developed for the quantitative determination of the spectral ionization probability {alpha}{sup +}({nu}) of sputtered particles as a function of the emission velocity. The next application of the TOF mass spectrometer is the analysis of complicated organic molecules in solid state surfaces. During measurements of the photo-ionization behaviour of neutral tryptophan molecules, it was found out that a stable molecular ion signal is generated in the SNMS spectrum with h{nu}=7.9 eV can only be observed by the use of a continuous ion beam or very long (ms range) ion pulses. (orig.)

First direct mass measurements on nobelium and lawrencium with the Penning trap mass spectrometer SHIPTRAP

Energy Technology Data Exchange (ETDEWEB)

Dworschak, Michael Gerhard

2009-12-08

The Penning trap mass spectrometer SHIPTRAP at GSI Darmstadt was set up for high-precision mass measurements of heavy radionuclides produced in fusion evaporation reactions and separated from the primary beam by the velocity filter SHIP. It consists of a gas stopping cell for the deceleration of the high energetic reaction products, an RFQ cooler and buncher for cooling and accumulation of the ions, and a double Penning trap system to perform mass measurements. The mass is determined by measuring the cyclotron frequency of the ion of interest in a strong homogeneous magnetic field and comparing it to the frequency of a well-known reference ion. With this method relative uncertainties in the order of 10{sup -8} can be achieved. Recently, mass measurements of the three nobelium isotopes {sup 252-254}No (Z=102) and the lawrencium isotope {sup 255}Lr (Z=103) were performed successfully. These were the first direct mass measurements of transuranium elements ever per- formed. The production rate of the atoms of interest was about one per second or less. The results of the measurements on nobelium confirm the previous mass values which were deduced from Q{sub {alpha}} values. In the case of {sup 255}Lr the mass excess value, which was previously only estimated from systematic trends, was for the first time directly measured. These results mark the first step in the exploration of the region of transuranium elements which is planned at SHIPTRAP. The main objective is to fix the endpoints of {alpha} decay chains which are originating from superheavy elements close to the predicted island of stability. (orig.)

Development of a new corona discharge based ion source for high resolution time-of-flight chemical ionization mass spectrometer to measure gaseous H2SO4 and aerosol sulfate

Science.gov (United States)

Zheng, Jun; Yang, Dongsen; Ma, Yan; Chen, Mindong; Cheng, Jin; Li, Shizheng; Wang, Ming

2015-10-01

A new corona discharge (CD) based ion source was developed for a commercial high-resolution time-of-flight chemical ionization mass spectrometer (HRToF-CIMS) (Aerodyne Research Inc.) to measure both gaseous sulfuric acid (H2SO4) and aerosol sulfate after thermal desorption. Nitrate core ions (NO3-) were used as reagent ions and were generated by a negative discharge in zero air followed by addition of excess nitrogen dioxide (NO2) to convert primary ions and hydroxyl radicals (OH) into NO3- ions and nitric acid (HNO3). The CD-HRToF-CIMS showed no detectable interference from hundreds parts per billion by volume (ppbv) of sulfur dioxide (SO2). Unlike the atmospheric pressure ionization (API) ToF-CIMS, the CD ion source was integrated onto the ion-molecule reaction (IMR) chamber and which made it possible to measure aerosol sulfate by coupling to a filter inlet for gases and aerosols (FIGAERO). Moreover, compared with a quadrupole-based mass spectrometer, the desired HSO4- signal was detected by its exact mass of m/z 96.960, which was well resolved from the potential interferences of HCO3-ṡ(H2O)2 (m/z 97.014) and O-ṡH2OṡHNO3 (m/z 97.002). In this work, using laboratory-generated standards the CD-HRToF-CIMS was demonstrated to be able to detect as low as 3.1 × 105 molecules cm-3 gaseous H2SO4 and 0.5 μg m-3 ammonium sulfate based on 10-s integration time and two times of the baseline noise. The CD ion source had the advantages of low cost and a simple but robust structure. Since the system was non-radioactive and did not require corrosive HNO3 gas, it can be readily field deployed. The CD-HRToF-CIMS can be a powerful tool for both field and laboratory studies of aerosol formation mechanism and the chemical processes that were critical to understand the evolution of aerosols in the atmosphere.

Fission product nuclear data obtained by use of an on-line mass spectrometer

International Nuclear Information System (INIS)

Reeder, P.L.; Wright, J.F.; Anderl, R.A.

1975-01-01

A Spectrometer for On-Line Analysis of Radionuclides (SOLAR) has been installed at a 1 MW TRIGA reactor at Washington State University. Fission product ions from a combination target/ion source located within the thermal column are brought out to a 60 0 magnetic sector mass spectrometer. Surface ionization provides copious beams of Rb + and Cs + ions and less intense beams of Br - and I - ions with negligible contamination by other elements. About 40 fission product nuclides can thus be chemically and physically separated in times of less than 1 second. Past results on independent and cumulative fission yields along with measurements of half-lives of some very neutron-rich nuclides are presented. Current work on delayed-neutron emission probabilities and energy spectra of delayed neutrons from individual nuclides is described. (7 tables, 2 figures) (U.S.)

Accurate mass measurements of short-lived isotopes with the MISTRAL rf spectrometer

CERN Document Server

Toader, C F; Borcea, C; Doubre, H; Duma, M; Jacotin, M; Henry, S; Képinski, J F; Lebée, G; Le Scornet, G; Lunney, M D; Monsanglant, C; De Saint-Simon, M; Thibault, C

1999-01-01

The MISTRAL experiment has measured its first masses at ISOLDE. Installed in May 1997, this radiofrequency transmission spectrometer is to concentrate on nuclides with particularly short half-lives. MISTRAL received its first stable beam in October and first radioactive beam in November 1997. These first tests, with a plasma ion source, resulted in excellent isobaric separation and reasonable transmission. Further testing and development enabled first data taking in July 1998 on neutron-rich Na isotopes having half-lives as short as 31 ms.

Advanced Laser Architecture for Two-Step Laser Tandem Mass Spectrometer

Science.gov (United States)

Fahey, Molly E.; Li, Steven X.; Yu, Anthony W.; Getty, Stephanie A.

2016-01-01

Future astrobiology missions will focus on planets with significant astrochemical or potential astrobiological features, such as small, primitive bodies and the icy moons of the outer planets that may host diverse organic compounds. These missions require advanced instrument techniques to fully and unambiguously characterize the composition of surface and dust materials. Laser desorptionionization mass spectrometry (LDMS) is an emerging instrument technology for in situ mass analysis of non-volatile sample composition. A recent Goddard LDMS advancement is the two-step laser tandem mass spectrometer (L2MS) instrument to address the need for future flight instrumentation to deconvolve complex organic signatures. The L2MS prototype uses a resonance enhanced multi-photon laser ionization mechanism to selectively detect aromatic species from a more complex sample. By neglecting the aliphatic and inorganic mineral signatures in the two-step mass spectrum, the L2MS approach can provide both mass assignments and clues to structural information for an in situ investigation of non-volatile sample composition. In this paper we will describe our development effort on a new laser architecture that is based on the previously flown Lunar Orbiter Laser Altimeter (LOLA) laser transmitter for the L2MS instrument. The laser provides two discrete midinfrared wavelengths (2.8 m and 3.4 m) using monolithic optical parametric oscillators and ultraviolet (UV) wavelength (266 nm) on a single laser bench with a straightforward development path toward flight readiness.

Improvements in the injection system of the Canadian Penning trap mass spectrometer

CERN Document Server

Clark, J; Boudreau, C; Buchinger, F; Crawford, J E; Gulick, S; Hardy, J C; Heinz, A; Lee, J K P; Moore, R B; Savard, G; Seweryniak, D; Sharma, K S; Sprouse, G; Vaz, J; Wang, J C; Zhou, Z

2003-01-01

The Canadian Penning Trap (CPT) mass spectrometer is designed to make precise mass measurements on a variety of stable and short-lived isotopes. Modifications to the injection system of the CPT have been implemented in recent months, the purpose being to more efficiently collect and transfer weakly-produced reaction products from the target to the Penning trap. These include a magnetic triplet situated after the target chamber to increase the acceptance of the Enge spectrograph, a velocity filter to more effectively separate the beam from the reaction products and the replacement of the Paul trap with a linear trap resulting in more efficient capture and accumulation of ions from the ion cooler. This paper will discuss these recent modifications and how they have increased our ability in making mass measurements on isotopes of low abundance, including those from a sup 2 sup 5 sup 2 Cf fission source.

Point-particle limit and the far-zone quadrupole formula in general relativity

International Nuclear Information System (INIS)

Futamase, T.

1985-01-01

Strong internal gravity is incorporated in a divergent-free post-Newtonian approximation scheme by introducing a body-zone limit. When incorporated into the notion of sequences of solutions, this provides the first rigorous point-particle limit in general relativity. The scheme is applied to construct an asymptotic approximation to a binary system composed of two rotating neutron stars. The lowest-order calculation is carried out in the near and far zones, giving Newton's equations of motion and the far-zone quadrupole formula. The quadrupole moment of the system is expressed in terms of a mass integral over each compact star. The same mass appears in Newton's equations of motion. The mass is indeed the Arnowitt-Deser-Misner mass the compact star would have if it were isolated. Thus the equivalence principle for strong gravity is confirmed, even for gravitational radiation: gravitational potential energy radiates the same amount of gravitational waves as any other form of energy does

Study of impurities in Aditya Tokamak during different conditions using quadrupole mass analyzer

International Nuclear Information System (INIS)

Bhatt, S.B.; Jadeja, K.A.; Patel, K.M.; Patel, N.D.; Raval, M.K.; Ghosh, J.

2015-01-01

In fusion devices, e.g., Tokamak, the presence of the impurities, i.e. gas species other than the fuel gas, deteriorates plasma and makes confinement difficult. The gas molecules tend to get adsorbed on the surfaces of the solid state materials of the vessel wall during discharges. A Residual Gas Analyzer (RGA) is the most commonly useful instrument to measure the presence and quantity of the various gases in a vacuum system. Quadrupole Mass Analyzer (QMA) is installed on Aditya Tokamak to measure the concentrations of various gas species present in Aditya vacuum system. It is also used to monitor impurities generated during various phases of discharges in Aditya Tokamak. The impurities are reduced by various types of discharge cleaning and in-situ coatings. Presence of residual gas concentration in vacuum system creates limitation for achievement of ultrahigh vacuum and also affects plasma performance. The presence of residual gases is due to different reasons like atmospheric concentration, contamination of the wall materials, outgassing from the exposed materials, permeation, real and virtual leaks

Analysis of U and Pu resin bead samples with a single stage mass spectrometer

International Nuclear Information System (INIS)

Smith, D.H.; Walker, R.L.; Bertram, L.K.; Carter, J.A.

1979-01-01

Resin bead sampling enables the shipment of nanogram U and Pu quantities for analysis. Application of this sampling technique to safeguards was investigated with a single-stage mass spectrometer. Standards gave results in good agreement with NBS certified values. External precisions of +-0.5% were obtained on isotopic ratios of approx. 0.01; precisions on quantitative measurements are +-1.0%

The first LHC insertion quadrupole

CERN Multimedia

2004-01-01

An important milestone was reached in December 2003 at the CERN Magnet Assembly Facility. The team from the Accelerator Technology - Magnet and Electrical Systems group, AT-MEL, completed the first special superconducting quadrupole for the LHC insertions which house the experiments and major collider systems. The magnet is 8 metres long and contains two matching quadrupole magnets and an orbit corrector, a dipole magnet, used to correct errors in quadrupole alignment. All were tested in liquid helium and reached the ultimate performance criteria required for the LHC. After insertion in the cryostat, the superconducting magnet will be installed as the Q9 quadrupole in sector 7-8, the first sector of the LHC to be put in place in 2004. Members of the quadrupole team, from the AT-MEL group, gathered around the Q9 quadrupole at its inauguration on 12 December 2003 in building 181.

Quadrupole deflector of the double Penning trap system MLLTRAP

Energy Technology Data Exchange (ETDEWEB)

Gartzke, Eva; Kolhinen, Veli; Habs, Dietrich; Neumayr, Juergen; Schuermann, Christian; Szerypo, Jerzy; Thirolf, Peter [Fakultaet fuer Physik, LMU Muenchen, Garching (Germany); Maier-Leibnitz Laboratory, Garching (Germany)

2009-07-01

A cylindrical double Penning trap has been installed and successfully commissioned at the Maier-Leibnitz Laboratory in Garching. This trap system has been designed to isobarically purify low energy ion beams and perform highly accurate mass measurements. An electrostatic quadrupole deflector has been designed and installed at the injection line of the Penning trap system enabling a simultaneous use of an online ion beam with reference ions from an offline ion source. Alternatively two offline sources can be used concurrently e.g. an {alpha} recoil sources providing heavy radioactive species (e.g {sup 240}U) together with reference mass ions (which in the future will be e.g. a carbon cluster ion source). The bender has been designed for beam energies up to 1 keV with q/A ratios 1/1-1/250. This presentation shows the technical design and the operating parameters of the quadrupole beam bender and its implementation at the MLLTRAP system.

Multidetector calibration for mass spectrometers

International Nuclear Information System (INIS)

Bayne, C.K.; Donohue, D.L.; Fiedler, R.

1994-06-01

The International Atomic Energy Agency's Safeguards Analytical Laboratory has performed calibration experiments to measure the different efficiencies among multi-Faraday detectors for a Finnigan-MAT 261 mass spectrometer. Two types of calibration experiments were performed: (1) peak-shift experiments and (2) peak-jump experiments. For peak-shift experiments, the ion intensities were measured for all isotopes of an element in different Faraday detectors. Repeated measurements were made by shifting the isotopes to various Faraday detectors. Two different peak-shifting schemes were used to measure plutonium (UK Pu5/92138) samples. For peak-jump experiments, ion intensities were measured in a reference Faraday detector for a single isotope and compared with those measured in the other Faraday detectors. Repeated measurements were made by switching back-and-forth between the reference Faraday detector and a selected Faraday detector. This switching procedure is repeated for all Faraday detectors. Peak-jump experiments were performed with replicate measurements of 239 Pu, 187 Re, and 238 U. Detector efficiency factors were estimated for both peak-jump and peak-shift experiments using a flexible calibration model to statistically analyze both types of multidetector calibration experiments. Calculated detector efficiency factors were shown to depend on both the material analyzed and the experimental conditions. A single detector efficiency factor is not recommended for each detector that would be used to correct routine sample analyses. An alternative three-run peak-shift sample analysis should be considered. A statistical analysis of the data from this peak-shift experiment can adjust the isotopic ratio estimates for detector differences due to each sample analysis

Quadrupole shunt experiments at SPEAR

International Nuclear Information System (INIS)

Corbett, W.J.; Hettel, R.O.; Nuhn, H.-D.

1996-05-01

As part of a program to align and stabilize the SPEAR storage ring, a switchable shunt resistor was installed on each quadrupole to bypass a small percentage of the magnet current. The impact of a quadrupole shunt is to move the electron beam orbit in proportion to the off-axis beam position at the quadrupole, and to shift the betatron tune. Initially, quadrupole shunts in SPEAR were used to position the electron beam in the center of the quadrupoles. This provided readback offsets for nearby beam position monitors, and helped to steer the photon beams with low-amplitude corrector currents. The shunt-induced tune shift measurements were then processed in MAD to derive a lattice model

MASS-SAT: Matter-antimatter space spectrometer on satellite

CERN Document Server

Basini, G; Massimo Brancaccio, F; Ricci, M; Bocciolini, M; Spillantini, P; Wang, Y F; Bongiorno, F; de Pascale, M P; Morselli, A; Picozza, P; de Marzo, C; Erriquez, O; Barbiellini, G; Vacchi, A; Galeotti, P; Ballocchi, G; Simon, M; Carlson, P; Goret, P; Golden, R L

The MASS-SAT Experiment (Matter-Antimatter Space Spectrometer on SATellite) presented here is conceived to search for an experimental answer to many open problems related to both Astrophysics and Physics, through the detection of positrons, antiprotons, nuclei and, overall, antinuclei if they exist. Among these problems there are the hypothesized presence of antigalaxies in the Universe (the matter-antimatter symmetry problem), the existence of black holes as possible antiproton sources (the Hawking effect), the existence of photinos as antiproton sources (related to the dark-matter problem), the understanding of the mechanism of cosmic-ray acceleration in the interstellar medium, the determination of the relative abundancies of isotopes in cosmic rays and many others. The choice of an orbit expecially appropriate for that (geostationary or polar orbit) as well as the choice of an apparatus composed only of solid-state detectors and permanent magnets (no gas and no liquid helium on board, avoiding complexity ...

Photoionization of H2O at high resolution

International Nuclear Information System (INIS)

Dehmer, P.M.; Chupka, W.A.

1978-01-01

The relative photoionization cross sections for the formation of H 2 O + , OH + , and H + from H 2 O were measured at high wavelength resolution using a 3-meter photoionization mass spectrometer equipped with a quadrupole mass flter and a 1-meter photoionization mass spectrometer equipped with a 12-inch radius, 60 0 sector magnetic mass spectrometer. Discrete structure in the parent ion photoionization efficiency curve is interpreted in terms of Rydberg series converging to excited states of the H 2 O + ion. 9 references

Development of novel nano-composite membranes as introduction systems for mass spectrometers: Contrasting nano-composite membranes and conventional inlet systems

Science.gov (United States)

Miranda, Luis Diego

This dissertation presents the development of novel nano-composite membranes as introduction systems for mass spectrometers. These nano-composite membranes incorporate anodic aluminum oxide (AAO) membranes as templates that can be used by themselves or modified by a variety of chemical deposition processes. Two types of nano-composite membranes are presented. The first nano-composite membrane has carbon deposited within the pores of an AAO membrane. The second nano-composite membrane is made by coating an AAO membrane with a thin polymer film. The following chapters describe the transmission properties these nano-composite membranes and compare them to conventional mass spectrometry introduction systems. The nano- composite membranes were finally coupled to the inlet system of an underwater mass spectrometer revealing their utility in field deployments.

A permanent magnet system for a cyclotron used as a mass spectrometer

International Nuclear Information System (INIS)

Li, C.Y.; Cooper, M.; Halbach, K.; Kunkel, W.B.; Leung, K.N.; Wells, R.P.; Young, A.T.

1992-07-01

The design of a compact, low energy cyclotron used as a mass spectrometer is presented. The instrument is designed for high resolution, high sensitivity detection of trace. It features the use of permanent magnets to excite the soft iron pole pieces which provide the magnetic field of the cyclotron. Tuning magnets are used to enable the field to be varied. This significantly improves the operational requirements of the instrument when compared to one which uses electromagnets. The cyclotron will use a spiral reflector for axial injection

Statistical program for the data evaluation of a thermal ionization mass spectrometer

Energy Technology Data Exchange (ETDEWEB)

van Raaphorst, J. G.

1978-12-15

A computer program has been written to statistically analyze mass spectrometer measurements. The program tests whether the difference between signal and background intensities is statistically significant, corrects for signal drift in the measured values, and calculates ratios against the main isotope from the corrected intensities. Repeated ratio value measurements are screened for outliers using the Dixon statistical test. Means of ratios and the coefficient of variation are calculated and reported. The computer program is written in Basic and is available for anyone who is interested.

Dual Source Time-of-flight Mass Spectrometer and Sample Handling System

Science.gov (United States)

Brinckerhoff, W.; Mahaffy, P.; Cornish, T.; Cheng, A.; Gorevan, S.; Niemann, H.; Harpold, D.; Rafeek, S.; Yucht, D.

We present details of an instrument under development for potential NASA missions to planets and small bodies. The instrument comprises a dual ionization source (laser and electron impact) time-of-flight mass spectrometer (TOF-MS) and a carousel sam- ple handling system for in situ analysis of solid materials acquired by, e.g., a coring drill. This DSTOF instrument could be deployed on a fixed lander or a rover, and has an open design that would accommodate measurements by additional instruments. The sample handling system (SHS) is based on a multi-well carousel, originally de- signed for Champollion/DS4. Solid samples, in the form of drill cores or as loose chips or fines, are inserted through an access port, sealed in vacuum, and transported around the carousel to a pyrolysis cell and/or directly to the TOF-MS inlet. Samples at the TOF-MS inlet are xy-addressable for laser or optical microprobe. Cups may be ejected from their holders for analyzing multiple samples or caching them for return. Samples are analyzed with laser desorption and evolved-gas/electron-impact sources. The dual ion source permits studies of elemental, isotopic, and molecular composition of unprepared samples with a single mass spectrometer. Pulsed laser desorption per- mits the measurement of abundance and isotope ratios of refractory elements, as well as the detection of high-mass organic molecules in solid samples. Evolved gas analysis permits similar measurements of the more volatile species in solids and aerosols. The TOF-MS is based on previous miniature prototypes at JHU/APL that feature high sensitivity and a wide mass range. The laser mode, in which the sample cup is directly below the TOF-MS inlet, permits both ablation and desorption measurements, to cover elemental and molecular species, respectively. In the evolved gas mode, sample cups are raised into a small pyrolysis cell and heated, producing a neutral gas that is elec- tron ionized and pulsed into the TOF-MS. (Any imaging

Evaluation of errors for mass-spectrometric analysis with surface-ionization type mass-spectrometer (statistical evaluation of mass-discrimination effect)

International Nuclear Information System (INIS)

Wada, Y.

1981-01-01

The surface-ionization type mass-spectrometer is widely used as an apparatus for quality assurance, accountability and safeguarding of nuclear materials, and for this analysis it has become an important factor to statistically evaluate an analytical error which consists of a random error and a systematic error. The major factor of this systematic error was the mass-discrimination effect. In this paper, various assays for evaluating the factor of variation on the mass-discrimination effect were studied and the data obtained were statistically evaluated. As a result of these analyses, it was proved that the factor of variation on the mass-discrimination effect was not attributed to the acid concentration of sample, sample size on the filament and supplied voltage for a multiplier, but mainly to the filament temperature during the mass-spectrometric analysis. The mass-discrimination effect values β which were usually calculated from the measured data of uranium, plutonium or boron isotopic standard sample were not so significant dependently of the difference of U-235, Pu-239 or B-10 isotopic abundance. Furthermore, in the case of U and Pu, measurement conditions and the mass range of these isotopes were almost similar, and these values β were not statistically significant between U and Pu. On the other hand, the value β for boron was about a third of the value β for U or Pu, but compared with the coefficient of the correction on the mass-discrimination effect for the difference of mass-number, ΔM, these coefficient values were almost the same among U, Pu, and B.As for the isotopic analysis error of U, Pu, Nd and B, it was proved that the isotopic abundance of these elements and the isotopic analysis error were in a relationship of quadratic curves on a logarithmic-logarithmic scale

Pollutants identification of ambient aerosols by two types of aerosol mass spectrometers over southeast coastal area, China.

Science.gov (United States)

Yan, Jinpei; Chen, Liqi; Lin, Qi; Zhao, Shuhui; Li, Lei

2018-02-01

Two different aerosol mass spectrometers, Aerodyne Aerosol Mass Spectrometer (AMS) and Single Particle Aerosol Mass Spectrometer (SPAMS) were deployed to identify the aerosol pollutants over Xiamen, representing the coastal urban area. Five obvious processes were classified during the whole observation period. Organics and sulfate were the dominant components in ambient aerosols over Xiamen. Most of the particles were in the size range of 0.2-1.0μm, accounting for over 97% of the total particles measured by both instruments. Organics, as well as sulfate, measured by AMS were in good correlation with measured by SPAMS. However, high concentration of NH 4 + was obtained by AMS, while extremely low value of NH 4 + was detected by SPAMS. Contrarily, high particle number counts of NO 3 - and Cl - were given by SPAMS while low concentrations of NO 3 - and Cl - were measured by AMS. The variations of POA and SOA obtained from SPAMS during event 1 and event 2 were in accordance with the analysis of HOA and OOA given by AMS, suggesting that both of AMS and SPAMS can well identify the organic clusters of aerosol particles. Overestimate or underestimate of the aerosol sources and acidity would be present in some circumstances when the measurement results were used to analyze the aerosol properties, because of the detection loss of some species for both instruments. Copyright © 2017. Published by Elsevier B.V.

[Structure identification of contaminants in a beverage product by liquid chromatography coupled with quadrupole time-of-flight mass spectrometry].

Science.gov (United States)

Miyamoto, Yasuhisa; Washida, Kazuto; Uyama, Atsuo; Mochizuki, Naoki

2014-01-01

The contaminants in a beverage product that had been reported to have a strange taste were identified. By comparative analysis with the normal product using liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (LC-QTOF-MS), six unknown compounds were detected in the total ion current chromatograms of the product in question. Detailed analysis of the mass spectra and product ion spectra of these compounds strongly suggested that the compounds were capric acid diethanolamide, lauric acid diethanolamide, myristic acid diethanolamide, lauryl dimethylaminoacetic acid, lauryl sulfate, and lauric acid, all of which are surfactants commonly used as ingredients of household detergents and shampoos. We searched commercially available detergent products to check for the presence of these six surfactants, and identified products that might have been intentionally or unintentionally mixed into the beverage product after opening.

Quadrupole shunt experiments at SPEAR

International Nuclear Information System (INIS)

Corbett, W.J.; Hettel, R.O.; Nuhn, H.

1997-01-01

As part of a program to align and stabilize the SPEAR storage ring, a switchable shunt resistor was installed on each quadrupole to bypass a small percentage of the magnet current. The impact of a quadrupole shunt is to move the electron beam orbit in proportion to the off-axis beam position at the quadrupole and to shift the betatron tune. Initially, quadrupole shunts in SPEAR were used to position the electron beam in the center of the quadrupoles. This provided readback offsets for nearby beam position monitors and helped to steer the photon beams with low-amplitude corrector currents. The shunt-induced tune shift measurements were then processed in MAD to derive a lattice model. copyright 1997 American Institute of Physics

Electric quadrupole strength in nuclei

International Nuclear Information System (INIS)

Kirson, M.W.

1979-01-01

Isoscalar electric quadrupole strength distributions in nuclei are surveyed, and it is concluded that the strength is shared, in most cases, roughly equally between low-lying transitions and the giant quadrupole state. The same is not true of the isovector case. A simple extension of the schematic model gives a remarkably successul description of the data, and emphasizes the vital importance of the coupling between high-lying and low-lying quadrupole modes. The standadrd simple representation of the giant quadrupole resonance as produced by operating on the nuclear ground state with the quadrupole transition operator is not applicable to the isoscalar case. It is suggested that giant resonances fall into broad classes of similar states, with considerable qualitative differences between the distinct classes. (author)

Design and realization of a space-borne reflectron time of flight mass spectrometer: electronics and measuring head; Conception et realisation d'un spectrometre de masse a temps de vol spatialisable de type 'reflectron' electronique et tete de mesure

Energy Technology Data Exchange (ETDEWEB)

Devoto, P

2006-03-15

The purpose of this thesis is the design of the electronics of a time of flight mass spectrometer, the making and the vacuum tests of a prototype which can be put onboard a satellite. A particular effort was necessary to decrease to the maximum the mass and electric consumption of the spectrometer, which led to the development of new circuits. The work completed during this thesis initially concerns the electronics of the measuring equipment which was conceived in a concern for modularity. A complete 'reflectron' type mass spectrometer was then designed, simulated and developed. The built prototype, which uses the developed electronics, was exposed to ion flows of different masses and energies in the CESR vacuum chambers. Its measured performances validate the implemented principles and show that an identical mass spectrometer can be put onboard a satellite with profit, for planetary or solar missions. (author)

Simultaneous Determination of Ten Constituents in Chaiqin Qingning Capsule by High-performance Liquid Chromatography Coupled with Triple-quadrupole Mass Spectrometry.

Science.gov (United States)

Li, Ting Yu; Huo, Xiao Kui; Zheng, Lu; Wang, Chao; Cong, Hai Jian; Xiang, Ting; Zhang, Lin; Zhang, Bao Jing; Huang, Shan Shan; Wu, Bin; Li, Xin Yu

2017-01-01

Chaiqin Qingning Capsule (CQQNC) was a prescription of Traditional Chinese Medicine with the effects of clearing away heat and removing toxin, harmonizing the exterior and interior, it was widely used in Asian, for example, China and Japan, different batches of the raws materials and different processing time may be the vital factor which raised a challenge to control the quality of the CQQNC. In this experiment, a high-performance liquid chromatography-mass spectrometry/MS (HPLC-MS/MS) method was developed to simultaneously determine ten bioactive components for the quality control of CQQNC. Chromatographic separation was achieved using an XBridge BEH C18 column (150 mm × 4.6 mm, 2.5 μm) with a mobile phase composed of 10 mm aqueous ammonium acetate and acetonitrile using a gradient elution in 20 min. This study was conducted by multiple reaction monitoring mode through electrospray ionization resource with a negative ionization mode. The established method was validated with good performance of precision, accuracy, stability, and reproducibility and was utilized to simultaneously quantify ten constituents of CQQNC obtained from seven different batches. It is the first time to report the rapid and simultaneous analysis of the ten compounds in CQQNC by HPLC-MS/MS and apply to determine 10 constituents in 7 batches of CQQNC bought from drug store in china. This method could be considered as good quality criteria to control the quality of CQQNC. In this paper, a simple, specific, and rapid high-performance liquid chromatogram coupled with triple-quadrupole mass spectrometry method for simultaneous quantification of ten constituents in Chaiqin Qingning Capsule has been developed for the first time. This method could be considered as good quality criteria to control the quality of CQQNC. Abbreviations used: CHM: Chinese herbal medicine; TCM: Traditional Chinese Medicine; CQQNC: Triple-quadrupole mass spectrometry Chaiqin Qingning Capsules; HPLC-MS/MS: High liquid

Simultaneous Determination of Ten Constituents in Chaiqin Qingning Capsule by High-performance Liquid Chromatography Coupled with Triple-quadrupole Mass Spectrometry

Science.gov (United States)

Li, Ting Yu; Huo, Xiao Kui; Zheng, Lu; Wang, Chao; Cong, Hai Jian; Xiang, Ting; Zhang, Lin; Zhang, Bao Jing; Huang, Shan Shan; Wu, Bin; Li, Xin Yu

2017-01-01

Background: Chaiqin Qingning Capsule (CQQNC) was a prescription of Traditional Chinese Medicine with the effects of clearing away heat and removing toxin, harmonizing the exterior and interior, it was widely used in Asian, for example, China and Japan, different batches of the raws materials and different processing time may be the vital factor which raised a challenge to control the quality of the CQQNC. Experimental Methods: In this experiment, a high-performance liquid chromatography-mass spectrometry/MS (HPLC-MS/MS) method was developed to simultaneously determine ten bioactive components for the quality control of CQQNC. Chromatographic separation was achieved using an XBridge BEH C18 column (150 mm × 4.6 mm, 2.5 μm) with a mobile phase composed of 10 mm aqueous ammonium acetate and acetonitrile using a gradient elution in 20 min. This study was conducted by multiple reaction monitoring mode through electrospray ionization resource with a negative ionization mode. Results: The established method was validated with good performance of precision, accuracy, stability, and reproducibility and was utilized to simultaneously quantify ten constituents of CQQNC obtained from seven different batches. Conclusion: It is the first time to report the rapid and simultaneous analysis of the ten compounds in CQQNC by HPLC-MS/MS and apply to determine 10 constituents in 7 batches of CQQNC bought from drug store in china. This method could be considered as good quality criteria to control the quality of CQQNC. SUMMARY In this paper, a simple, specific, and rapid high-performance liquid chromatogram coupled with triple-quadrupole mass spectrometry method for simultaneous quantification of ten constituents in Chaiqin Qingning Capsule has been developed for the first time. This method could be considered as good quality criteria to control the quality of CQQNC. Abbreviations used: CHM: Chinese herbal medicine; TCM: Traditional Chinese Medicine; CQQNC: Triple-quadrupole mass

Chemical analysis of surfaces by resonance ionization mass spectroscopy associated to ionic pulverization; Analyse chimique de surfaces par spectrometrie d`ionisation resonante associee a la pulverisation ionique

Energy Technology Data Exchange (ETDEWEB)

Kern, P

1995-12-19

This work shows that if resonance ionization mass spectroscopy was first applied in isotopic separation, it`s also an analyzing method adapted to the study of semi-conductor materials and thin foils. We have improved this technic: a neodymium laser coupled with a dye laser, a new argon ions gun, a gallium ions gun and a new collection optic for the secondary ions quadrupole spectrometer to allow quantitative and selective measurements. (S.G.). 84 refs.

Correlation between mass-spectrometer measurements and thin film characteristics using dcMS and HiPIMS discharges

International Nuclear Information System (INIS)

Ferrec, A.; Keraudy, J.; Jacq, S.; Jouan, P.Y.; Djouadi, M.A.; Schuster, F.

2014-01-01

In this work, chromium thin films were deposited using dcMS and HiPIMS technologies. To compare these technologies, we analyzed the ion flux and the Cr coating microstructure in the same plasma conditions. Ion flux was measured with a mass spectrometer in time-averaged for both discharge and time-resolved for HiPIMS discharge. Time-averaged measurements provided important information. First, the low energetic part of the ion energy distribution function (IEDF) was similar in dcMS and HiPIMS and second the high energetic component was more prominent in the HiPIMS discharge. Time-resolved measurements showed that the high energetic part of the ion flux reached the mass spectrometer faster than the lowest part. It is only after the pulse end that most of the thermalized ions arrived and then cooled the flux. The correlation of these results with microstructure analysis shows that energetic particles induced a higher film density and a smoother surface in HiPIMS compared to dcMS discharge. (authors)

Real-time monitoring of trace-level VOCs by an ultrasensitive compact lamp-based VUV photoionization mass spectrometer

Science.gov (United States)

Sun, W. Q.; Shu, J. N.; Zhang, P.; Li, Z.; Li, N. N.; Liang, M.; Yang, B.

2015-06-01

In this study, we report on the development of a compact lamp-based vacuum ultraviolet (VUV) photoionization mass spectrometer (PIMS; hereafter referred to as VUV-PIMS) in our laboratory; it is composed of a radio frequency-powered VUV lamp, a VUV photoionizer, an ion-immigration region, and a reflection time-of-flight mass spectrometer. By utilizing the novel photoionizer consisting of a photoionization cavity and a VUV light baffle, extremely low background noise was obtained. An ultrasensitive detection limit (2σ) of 3 pptv was achieved for benzene after an acquisition time of 10 s. To examine its potential for application in real-time sample monitoring, the developed VUV-PIMS was employed for the continuous measurement of urban air for six days in Beijing, China. Strong signals of trace-level volatile organic compounds such as benzene and its alkylated derivatives were observed in the mass spectra. These initial experimental results reveal that the instrument can be used for the online monitoring of trace-level species in the atmosphere.

Analysis of polycyclic aromatic hydrocarbons using desorption atmospheric pressure chemical ionization coupled to a portable mass spectrometer.

Science.gov (United States)

Jjunju, Fred P M; Maher, Simon; Li, Anyin; Badu-Tawiah, Abraham K; Taylor, Stephen; Cooks, R Graham

2015-02-01

Desorption atmospheric pressure chemical ionization (DAPCI) is implemented on a portable mass spectrometer and applied to the direct detection of polycyclic aromatic hydrocarbons (PAHs) and alkyl substituted benzenes. The presence of these compounds in the environment poses a significant threat to the health of both humans and wildlife because of their carcinogenic, toxic, and mutagenic properties. As such, instant detection outside of the laboratory is of particular importance to allow in-situ measurement at the source. Using a rapid, high throughput, miniature, handheld mass spectrometer, several alkyl substituted benzenes and PAHs (i.e., 1,2,3,5-tetramethylbenzene, pentamethylbenzene, hexamethylbenzene, fluoranthene, anthracene, benzo[k]fluoranthene, dibenz[a,h]anthracene, acenaphthene, indeno[1,2,3-c,d]pyrene, 9-ethylfluorene, and 1-benzyl-3-methyl-naphthalene) were identified and characterized using tandem mass spectrometry (MS/MS) from ambient surfaces, in the open air. This method can provide almost instantaneous information while minimizing sample preparation, which is advantageous in terms of both cost and simplicity of analysis. This MS-based technique is applicable to a wide range of environmental organic molecules.

Detection of methyl-, dimethyl- and diethylamine using a nitrate-based chemical ionization mass spectrometer

Science.gov (United States)

Jokinen, T.; Smith, J. N.

2016-12-01

New particle formation is one of the main sources of cloud condensation nuclei (CCN) contributing approximately half of the global CCN budget. The initial steps of nucleation have been studied for decades and it is widely accepted that in most places nucleation requires presence of sulphuric acid (SA) and cluster-stabilizing vapours. Recent results from the CLOUD chamber show that only a few pptv levels of dimethylamine (DMA) with SA forms stable clusters at boundary layer conditions. Ambient sulphuric acid is typically measured using nitrate-based chemical ionization mass spectrometers. Unfortunately, because of higher volatilities and stickiness of amines to surfaces, amine measurement techniques suffer from memory effects and high detection limits. Recently it was discovered that DMA can be detected by utilizing nitrate ionization, simultaneously with sulphuric acid measurements. Here we present results of detecting methylamine, dimethylamine and diethylamine using nitrate-based chemical ionization. We conducted a series of measurements with a home-built transverse chemical ionization inlet and a high resolution time-of-flight mass spectrometer (CI-HToF). Amine vapour was produced using permeation tubes. Three stages of dilution were applied at roughly one order-of-magnitude dilution per stage. The diluted flow of selected amine was then introduced to a sample flow rate of 7 slpm, thus achieving a final amine concentration of 10 pptv. All selected amines were detected as clusters with HNO3NO3- and showed linear response with increasing concentrations (0.5-minute integration time). Zero measurements were performed using clean nitrogen gas right after injection of a selected amine. Memory effects were only observed when using high amine concentrations (ppbv levels). Our results indicate that a variety of amines can be detected using nitrate-based chemical ionization mass spectrometers. However, more experiments are required to see if this presented method will be

Results of Magnetic Axis Measurements on a Prototype Main Lattice Quadrupole for the LHC

CERN Document Server

Smirnov, N; Deferne, G; Parma, V; Rohmig, P; Tortschanoff, Theodor

2004-01-01

More than 470 twin aperture lattice quadrupoles are needed for the Large Hadron Collider (LHC) under construction at CERN. The lattice quadrupole, assembled with correction magnets in its helium enclosure - the cold mass and integrated in a common cryostat called the Short Straight Section (SSS). All SSS cold mass prototypes have been developed and built by CEA (Saclay) in collaboration with CNRS (Orsay, France). The last SSS prototype (SSS5) was used to investigate the behavior of the magnetic axis through various steps of the installation cycle for the series quadrupoles: including transportation, thermal-cycles, and being lowered into the tunnel. Results of extensive measurements before and after each of these stages are presented here, showing that the effect of transport is weak and within the window of measurement resolution. Also shown is that the long-term stability observed during two years is comparable with the requirements from magnet tolerances. To minimize systematic errors, all tests were perfo...

A Micro-Cylindrical Ion Trap (µ-CIT) Micro-Mass Spectrometer Instrument System (µ-MSIS) for NASA Planetary Exploration

Data.gov (United States)

National Aeronautics and Space Administration — The goal of this follow-on early stage innovation activity is to advance the development of new, extremely small, low power, and low cost "micro" mass spectrometer...

Mass Spectrometric Analysis of Eight Common Chemical Explosives Using Ion Trap Mass Spectrometer

Energy Technology Data Exchange (ETDEWEB)

Park, Sehwan; Lee, Jihyeon; KIm, Jeongkwon [Chungnam National Univ., Daejeon (Korea, Republic of); Cho, Soo Gyeong; Goh, Eun Mee [Agency for Defense Development, Daejeon (Korea, Republic of); Lee, Sungman; Koh, Sungsuk [Sensor Tech Inc., Seoul (Korea, Republic of)

2013-12-15

Eight representative explosives (ammonium perchlorate (AP), ammonium nitrate (AN), trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), cyclonite (RDX), cyclotetramethylenetetranitramine (HMX), pentaerythritol tetranitrate (PETN), and hexanitrostilbene (HNS)) were comprehensively analyzed with an ion trap mass spectrometer in negative ion mode using direct infusion electrospray ionization. MS/MS experiments were performed to generate fragment ions from the major parent ion of each explosive. Explosives in salt forms such as AP or AN provided cluster parent ions with their own anions. Explosives with an aromatic ring were observed as either [M.H]{sup -} for TNT and DNT or [M]{sup ·-}. for HNS, while explosives without an aromatic ring such as RDX, HMX, and PETN were detected as an adduct ion with a formate anion, i. e., [M+HCOO]{sup -}. These findings provide a guideline for the rapid and accurate detection of explosives once portable MS instruments become more readily available.

Mass Spectrometric Analysis of Eight Common Chemical Explosives Using Ion Trap Mass Spectrometer

International Nuclear Information System (INIS)

Park, Sehwan; Lee, Jihyeon; KIm, Jeongkwon; Cho, Soo Gyeong; Goh, Eun Mee; Lee, Sungman; Koh, Sungsuk

2013-01-01

Eight representative explosives (ammonium perchlorate (AP), ammonium nitrate (AN), trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), cyclonite (RDX), cyclotetramethylenetetranitramine (HMX), pentaerythritol tetranitrate (PETN), and hexanitrostilbene (HNS)) were comprehensively analyzed with an ion trap mass spectrometer in negative ion mode using direct infusion electrospray ionization. MS/MS experiments were performed to generate fragment ions from the major parent ion of each explosive. Explosives in salt forms such as AP or AN provided cluster parent ions with their own anions. Explosives with an aromatic ring were observed as either [M.H] - for TNT and DNT or [M] ·- . for HNS, while explosives without an aromatic ring such as RDX, HMX, and PETN were detected as an adduct ion with a formate anion, i. e., [M+HCOO] - . These findings provide a guideline for the rapid and accurate detection of explosives once portable MS instruments become more readily available

Determination of suspected allergens in cosmetic products by headspace-programmed temperature vaporization-fast gas chromatography-quadrupole mass spectrometry.

Science.gov (United States)

del Nogal Sánchez, Miguel; Pérez-Pavón, José Luis; Moreno Cordero, Bernardo

2010-07-01

In the present work, a strategy for the qualitative and quantitative analysis of 24 volatile compounds listed as suspected allergens in cosmetics by the European Union is reported. The list includes benzyl alcohol, limonene, linalool, methyl 2-octynoate, beta-citronellol, geraniol, citral (two isomers), 7-hydroxycitronellal, anisyl alcohol, cinnamal, cinnamyl alcohol, eugenol, isoeugenol (two isomers), coumarin, alpha-isomethyl ionone, lilial, alpha-amylcinnamal, lyral, alpha-amylcinnamyl alcohol, farnesol (three isomers), alpha-hexyl cinnamal, benzyl cinnamate, benzyl benzoate, and benzyl salicylate. The applicability of a headspace (HS) autosampler in combination with a gas chromatograph (GC) equipped with a programmable temperature vaporizer (PTV) and a quadrupole mass spectrometry (qMS) detector is explored. By using a headspace sampler, sample preparation is reduced to introducing the sample into the vial. This reduces the analysis time and the experimental errors associated with this step of the analytical process. Two different injection techniques were used: solvent-vent injection and hot-split injection. The first offers a way to improve sensitivity at the same time maintaining the simple headspace instrumentation and it is recommended for compounds at trace levels. The use of a liner packed with Tenax-TA allowed the compounds of interest to be retained during the venting process. The signals obtained when hot-split injection was used allowed quantification of all the compounds according to the thresholds of the European Cosmetics Directive. Monodimensional gas chromatography coupled to a conventional quadrupole mass spectrometry detector was used and the 24 analytes were separated appropriately along a run time of about 12 min. Use of the standard addition procedure as a quantification technique overcame the matrix effect. It should be emphasized that the method showed good precision and accuracy. Furthermore, it is rapid, simple, and--in view of the

Profiling the indole alkaloids in yohimbe bark with ultra-performance liquid chromatography coupled with ion mobility quadrupole time-of-flight mass spectrometry.

Science.gov (United States)

Sun, Jianghao; Baker, Andrew; Chen, Pei

2011-09-30

An ultra-performance liquid chromatography/ion mobility quadrupole time-of-flight mass spectrometry (UPLC/IM-QTOF-MS) method was developed for profiling the indole alkaloids in yohimbe bark. Many indole alkaloids with the yohimbine or ajmalicine core structure, plus methylated, oxidized and reduced species, were characterized. Common fragments and mass differences are described. It was shown that the use of IMS could provide another molecular descriptor, i.e. molecular shape by rotationally averaged collision cross-section; this is of great value for identification of constituents when reference materials are usually not available. Using the combination of high resolution (~40000) accurate mass measurement with time-aligned parallel (TAP) fragmentation, MS(E) (where E represents collision energy), ion mobility mass spectrometry (IMS) and UPLC chromatography, a total 55 indole alkaloids were characterized and a few new indole alkaloids are reported for the first time. Published in 2011 by John Wiley & Sons, Ltd.

Mass spectrometer determinations of solar wind He, Ne, and Ar and radiation belt He

International Nuclear Information System (INIS)

Warasila, R.L.

1976-01-01

A unique mass spectrometer system was built and used to measure He, Ne, and Ar abundances and isotopic ratios in various samples of spacecraft that have been exposed to the space environment. The Apollo 12 mission brought back sections of the Surveyor 3 vehicle suitable for mass spectrometric studies of implanted solar wind and solar cosmic ray particles. Using the mass spectrometer, a 4 He flux of 6-8 x 10 6 ions/cm 2 --sec was measured, and in addition 4 He/ 3 He = 2700 +- 50; 4 He/ 20 Ne = 410 + 30; 20 Ne/ 22 Ne = 13.5 +- 0.2; 20 Ne/ 36 Ar = 24.5 +- 2.5; and 36 Ar/ 38 Ar = 5.41 +- 0.20 isotopic abundances were measured. An upper limit for the flux of SCR 3 He in the 10-20 MeV/nucleon range was also determined, for the thirty-one month exposure period. In the radiation belt environment, 3 He was found in the aluminum antenna housing from the recovered second stage of a pre-Apollo Saturn test flight launched January 28, 1964 and returned to earth on April 28, 1966. The amount of 3 He found was about 6 x 10 -10 cc(STP)/cm 2 with a 4 He/ 3 He ratio of 145 or less. The 3 He was shown to come from the lower radiation belt as all other sources of 3 He were orders of magnitude lower than the observed value

GoAmazon 2014/15 Thermal Desorption Chemical Ionization Mass Spectrometer (TDCIMS) Field Campaign Report

Energy Technology Data Exchange (ETDEWEB)

Smith, JN [Univ. of California, Irvine, CA (United States)

2016-04-01

The Thermal Desorption Chemical Ionization Mass Spectrometer (TDCIMS) deployment to the U.S. Department of Energy (DOE)’s Atmospheric Radiation Measurement (ARM) Climate Research Facility T3 site in Manacapuru, Brazil, was motivated by two main scientific objectives of the Green Ocean Amazon (GoAmazon) 2014/15 field campaign. 1) Study the interactions between anthropogenic and biogenic emissions by determining important molecular species in ambient nanoparticles. To address this, TDCIMS data will be combined with coincident measurements such as gas-phase sulfuric acid to determine the contribution of sulfuric acid condensation to nucleation and growth. We can then compare that result to TDCIMS-derived nanoparticle composition to determine the fraction of growth that can be attributed to the uptake of organic compounds. The molecular composition of sampled particles will also be used to attribute specific chemical species and mechanisms to growth, such as the condensation of low-volatility species or the oligomerization of α-dicarbonyl compounds. 2) Determine the source of new ambient nanoparticles in the Amazon. The hypothesis prior to measurements was that potassium salts formed from the evaporation of primary particles emitted by fungal spores can provide a unique and important pathway for new particle production in the Amazon basin. To explore this hypothesis, the TDCIMS recorded the mass spectra of sampled ambient particles using a protonated water cluster Chemical Ionization Mass Spectrometer (CIMS). Laboratory tests performed using potassium salts show that the TDCIMS can detect potassium with high sensitivity with this technique.

On-target digestion of collected bacteria for MALDI mass spectrometry.

Science.gov (United States)

Dugas, Alton J; Murray, Kermit K

2008-10-03

An on-target protein digestion system was developed for the identification of microorganisms in collected bioaerosols using off-line matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Bacteria analysis techniques based on MALDI-MS were adapted for use with an orthogonal MALDI quadrupole-time-of-flight mass spectrometer. Bioaerosols were generated using a pneumatic nebulizer and infused into a chamber for sampling. An Andersen N6 single-stage impactor was used to collect the bioaerosols on a MALDI target. On-target digestion was carried out inside temporary mini-wells placed over the impacted samples. The wells served as miniature reactors for proteolysis. Collected test aerosol particles containing the protein cytochrome c and E. coli bacteria were proteolyzed in situ using trypsin or cyanogen bromide. A total of 19 unique proteins were identified for E. coli. Using the TOF-MS spectra of the digested samples, peptide mass mapping was performed using the MASCOT search engine and an iterative search technique.

Expanding Single Particle Mass Spectrometer Analyses for the Identification of Microbe Signatures in Sea Spray Aerosol.

Science.gov (United States)

Sultana, Camille M; Al-Mashat, Hashim; Prather, Kimberly A

2017-10-03

Ocean-derived microbes in sea spray aersosol (SSA) have the potential to influence climate and weather by acting as ice nucleating particles in clouds. Single particle mass spectrometers (SPMSs), which generate in situ single particle composition data, are excellent tools for characterizing aerosols under changing environmental conditions as they can provide high temporal resolution and require no sample preparation. While SPMSs have proven capable of detecting microbes, these instruments have never been utilized to definitively identify aerosolized microbes in ambient sea spray aersosol. In this study, an aerosol time-of-flight mass spectrometer was used to analyze laboratory generated SSA produced from natural seawater in a marine aerosol reference tank. We present the first description of a population of biological SSA mass spectra (BioSS), which closely match the ion signatures observed in previous terrestrial microbe studies. The fraction of BioSS dramatically increased in the largest supermicron particles, consistent with field and laboratory measurements of microbes ejected by bubble bursting, further supporting the assignment of BioSS mass spectra as microbes. Finally, as supported by analysis of inorganic ion signals, we propose that dry BioSS particles have heterogeneous structures, with microbes adhered to sodium chloride nodules surrounded by magnesium-enriched coatings. Consistent with this structure, chlorine-containing ion markers were ubiquitous in BioSS spectra and identified as possible tracers for distinguishing recently aerosolized marine from terrestrial microbes.

Hybrid quadrupole-orbitrap mass spectrometry analysis with accurate-mass database and parallel reaction monitoring for high-throughput screening and quantification of multi-xenobiotics in honey.

Science.gov (United States)

Li, Yi; Zhang, Jinzhen; Jin, Yue; Wang, Lin; Zhao, Wen; Zhang, Wenwen; Zhai, Lifei; Zhang, Yaping; Zhang, Yongxin; Zhou, Jinhui

2016-01-15

This study reports a rapid, automated screening and quantification method for the determination of multi-xenobiotic residues in honey using ultra-high performance liquid chromatography-hybrid quadrupole-Orbitrap mass spectrometry (UHPLC-Q-Orbitrap) with a user-built accurate-mass database plus parallel reaction monitoring (PRM). The database contains multi-xenobiotic information including formulas, adduct types, theoretical exact mass and retention time, characteristic fragment ions, ion ratios, and mass accuracies. A simple sample preparation method was developed to reduce xenobiotic loss in the honey samples. The screening method was validated based on retention time deviation, mass accuracy via full scan-data-dependent MS/MS (full scan-ddMS2), multi-isotope ratio, characteristic ion ratio, sensitivity, and positive/negative switching performance between the spiked sample and corresponding standard solution. The quantification method based on the PRM mode is a promising new quantitative tool which we validated in terms of selectivity, linearity, recovery (accuracy), repeatability (precision), decision limit (CCα), detection capability (CCβ), matrix effects, and carry-over. The optimized methods proposed in this study enable the automated screening and quantification of 157 compounds in less than 15 min in honey. The results of this study, as they represent a convenient protocol for large-scale screening and quantification, also provide a research approach for analysis of various contaminants in other matrices. Copyright © 2015 Elsevier B.V. All rights reserved.

Surface-Induced Dissociation of Protein Complexes in a Hybrid Fourier Transform Ion Cyclotron Resonance Mass Spectrometer

Energy Technology Data Exchange (ETDEWEB)

Yan, Jing; Zhou, Mowei; Gilbert, Joshua D.; Wolff, Jeremy J.; Somogyi, Árpád; Pedder, Randall E.; Quintyn, Royston S.; Morrison, Lindsay J.; Easterling, Michael L.; Paša-Tolić, Ljiljana; Wysocki, Vicki H.

2017-01-03

Mass spectrometry continues to develop as a valuable tool in the analysis of proteins and protein complexes. In protein complex mass spectrometry studies, surface-induced dissociation (SID) has been successfully applied in quadrupole time-of-flight (Q-TOF) instruments. SID provides structural information on non-covalent protein complexes that is complementary to other techniques. However, the mass resolution of Q-TOF instruments can limit the information that can be obtained for protein complexes by SID. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) provides ultrahigh resolution and ultrahigh mass accuracy measurements. In this study, an SID device was designed and successfully installed in a hybrid FT-ICR instrument in place of the standard gas collision cell. The SID-FT-ICR platform has been tested with several protein complex systems (homooligomers, a heterooligomer, and a protein-ligand complex, ranging from 53 kDa to 85 kDa), and the results are consistent with data previously acquired on Q-TOF platforms, matching predictions from known protein interface information. SID fragments with the same m/z but different charge states are well-resolved based on distinct spacing between adjacent isotope peaks, and the addition of metal cations and ligands can also be isotopically resolved with the ultrahigh mass resolution available in FT-ICR.

SPS Quadrupole Magnets

CERN Multimedia

1974-01-01

A stack of SPS Quadrupole Magnets ready for installation in the tunnel. The SPS uses a total of 216 laminated normal conducting lattice quadrupoles with a length of 3.13 m for the core, 3.3 m overall. The F and D quads. have identical characteristics: inscribed circle radius 44 mm, core height and width 800 mm, maximum gradient 20 Tesla/m.

Mass measurement errors of Fourier-transform mass spectrometry (FTMS): distribution, recalibration, and application.

Science.gov (United States)

Zhang, Jiyang; Ma, Jie; Dou, Lei; Wu, Songfeng; Qian, Xiaohong; Xie, Hongwei; Zhu, Yunping; He, Fuchu

2009-02-01

The hybrid linear trap quadrupole Fourier-transform (LTQ-FT) ion cyclotron resonance mass spectrometer, an instrument with high accuracy and resolution, is widely used in the identification and quantification of peptides and proteins. However, time-dependent errors in the system may lead to deterioration of the accuracy of these instruments, negatively influencing the determination of the mass error tolerance (MET) in database searches. Here, a comprehensive discussion of LTQ/FT precursor ion mass error is provided. On the basis of an investigation of the mass error distribution, we propose an improved recalibration formula and introduce a new tool, FTDR (Fourier-transform data recalibration), that employs a graphic user interface (GUI) for automatic calibration. It was found that the calibration could adjust the mass error distribution to more closely approximate a normal distribution and reduce the standard deviation (SD). Consequently, we present a new strategy, LDSF (Large MET database search and small MET filtration), for database search MET specification and validation of database search results. As the name implies, a large-MET database search is conducted and the search results are then filtered using the statistical MET estimated from high-confidence results. By applying this strategy to a standard protein data set and a complex data set, we demonstrate the LDSF can significantly improve the sensitivity of the result validation procedure.

An Improvement on Space Focusing Resolution in Two-Field Time-of-Flight Mass Spectrometers

International Nuclear Information System (INIS)

Yildirim, M.; Aydin, R.; Akin, U.; Kilic, H. S.; Sise, O.; Ulu, M.; Dogan, M.

2007-01-01

Time-of-Flight Mass Spectrometer (TOFMS) is a sophisticated device for the mass selective analysis of a variety of samples. The main limitation on TOFMS technique is the obtainable resolution where the two main limiting factors are the initial space and energy spread of particles created in ionization region. Similar charged particles starting at different points will reach the detector at different times. So, this problem makes space focusing is very important subject. We have presented principles of two-fields TOFMS with second-order space focusing both using analytical methods and ray-tracing simulation. This work aims understanding of ion optical system clearly and gives hint of expectation for future developments

Improving the signal-to-noise ratio in mass and ion kinetic energy spectrometers

International Nuclear Information System (INIS)

Brenton, A.G.; Beynon, J.H.; Morgan, R.P.

1979-01-01

The signal-to-noise ratio in mass and ion kinetic energy spectrometers is limited by noise generated from the presence of scattered ions and neutrals. Methods of eliminating this are illustrated with reference to the ZAB-2F instrument manufactured by VG-Micromass Ltd. It is estimated that after the modifications the instrument is capable, on a routine basis, of measuring peaks corresponding to the arrival of ions at a rate of the order of 1 ion s -1 . (Auth.)

Measurement of high-mass dilepton production with the CMS-TOTEM Precision Proton Spectrometer

CERN Document Server

Shchelina, Ksenia

2017-01-01

The measurements of dilepton production in photon-photon fusion with the CMS-TOTEM Precision Proton Spectrometer (CT-PPS) are presented. For the first time, exclusive dilepton production at high masses have been observed in the CMS detector while one or two outgoing protons are measured in CT-PPS using around 10~${\\rm fb}^{-1}$ of data accumulated in 2016 during high-luminosity LHC operation. These first results show a good understanding, calibration and alignment of the new CT-PPS detectors installed in 2016.

Structural elucidation and identification of a new derivative of phenethylamine using quadrupole time-of-flight mass spectrometry.

Science.gov (United States)

Sekuła, Karolina; Zuba, Dariusz

2013-09-30

In recent years, the phenomenon of uncontrolled distribution of new psychoactive substances that were marketed without prior toxicological studies has been observed. Because many designer drugs are related in chemical structure, the potential for misidentifying them is an important problem. It is therefore essential to develop an analytical procedure for unequivocal elucidation of the structures of these compounds. The issue has been discussed in the context of 25I-NBMD [2-(4-iodo-2,5-dimethoxyphenyl)-N-[(2,3-methylenedioxyphenyl)methyl]ethanamine], a psychoactive substance first discovered on the drug market in 2012. The substance was extracted from blotter papers with methanol. Separation was achieved via liquid chromatography. Analysis was conducted by electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-QTOFMS). Identification of the psychoactive component was supported by electron impact gas chromatography/mass spectrometry (GC/EI-MS). The high accuracy of the LC/ESI-QTOFMS method allowed the molecular mass of the investigated substance (M(exp) = 441.0438 Da; mass error, ∆m = 0.2 ppm) and the formulae of ions formed during fragmentation to be determined. The main ions were recorded at m/z = 135.0440, 290.9876 and 305.9981. Structures of the obtained ions were elucidated in the tandem mass spectrometry (MS/MS) experiments by comparing them to mass spectra of previously detected derivatives of phenethylamine. The performed study indicated the potential for using LC/QTOFMS method to identify new designer drugs. This technique can be used supplementary to standard GC/MS. Prior knowledge of the fragmentation mechanisms of phenethylamines allowed to predict the mass spectra of the novel substance--25I-NBMD. Copyright © 2013 John Wiley & Sons, Ltd.

Turning an energy analyzer into a mass spectrometer and a charge sorter