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1
Labusov, V. A., A. A. Dzyuba, V. G. Garanin, O. V. Pelipasov, I. A. Zarubin, A. V. Borisov, S. S. Boldova et al. « Optical spectrometers Grand : a new tool for measuring mass fractions of analytes ». Аналитика и контроль 28, no 3 (2024) : 259–69. https://doi.org/10.15826/analitika.2024.28.3.004.
Texte intégralRésumé :
In 2023, optical spectrometers Grand were included in the Russian State Register of Measuring Instruments under No. 89108-23 as a tool for measuring the mass fractions of analytes in natural and industrial materials. These spectrometers are manufactured by VMK-Optoelektronika company in ten modifications, nine of which are atomic emission spectrometers and one is an atomic absorption spectrometer: Atomic emission spectrometers a. Grand-Globula, Grand-Kristall, and Grand-Express arc and spark discharge spectrometers for direct (without preliminary chemical preparation) analysis of powder samples and metals; b. Grand-Potok arc discharge spectrometer for rapid analysis of powder samples using the spill-injection method; c. Grand-Expert and Grand-Favorit vacuum argon spark discharge spectrometers for rapid analysis of metals and alloys; d. Grand-MP nitrogen microwave plasma spectrometer and Grand-ICP inductively coupled argon plasma spectrometer for analysis of liquid samples; e. Grand-Pavlin flame emission spectrometer for determination of alkali and alkaline earth elements in solutions. Grand-AAS high-resolution continuum source electrothermal atomic absorption spectrometer for simultaneous multielement determination in liquids. Atomic emission spectrometers have various spectrum excitation sources based on almost all atomization and excitation methods known in atomic emission spectrometry. Grand-AAS atomic absorption spectrometer is the world's first commercial instrument that allows the simultaneous determination of more than 40 elements in a liquid in one electrothermal atomization cycle with analytical performance close to that of modern electrothermal atomic absorption spectrometers for the sequential determination of elements.
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Labusov, V. A., A. V. Behterev et V. G. Garanin. « Spectrometers with MAES analyzers based on new photodetector arrays ». Аналитика и контроль 25, no 4 (2021) : 262–72. http://dx.doi.org/10.15826/analitika.2021.25.4.002.
Texte intégralRésumé :
Multichannel analyzers of emission spectra (MAES) are operated as part of more than six hundred systems for atomic emission spectral analysis at enterprises in Russia, the CIS countries, and others. Until recently, MAES analyzers used only BLPP-369M1 photodetector arrays, whose performance is sufficient for integral atomic emission spectrometry applications using bright sources of spectral excitation based, for example, on an arc or spark electric discharge. To solve problems where high temporal spatial resolution and high sensitivity are required, high-speed MAES analyzers have been developed based on two new photodetector arrays—BLPP-2000 and BLPP-4000. A number of optical spectrometers based on these arrays have been developed and put into production by the VMK-Optoelektronika company: Atomic emission spectrometers: Grand Globula and Ekspress arc and spark spectrometers for the direct analysis of powders by evaporation from the channel of a graphite electrode and for the analysis of metals; Grand-Potok arc spectrometers for the rapid analysis of powders by the spill-injection method; Grand-Ekspert and Favorit argon-spark vacuum spectrometers for the rapid analysis of metals and alloys; Grand-SVCh microwave-induced nitrogen plasma spectrometers and Grand-ISP inductively-coupled argon plasma spectrometers for the analysis of liquids; Kolibri-SVCh microwave-induced air plasma spectrometers and Pavlin flame atomic emission spectrometers for the determination of alkaline and alkaline earth elements in solutions. Grand-AAS high-resolution continuous-source electrothermal atomic absorption spectrometers for the simultaneous determination of elements in liquids.
3
Makarov, V. A., et T. K. Savosteenko. « Determination of phosphorus mass fraction in steels of plasma atomic emission spectrometry ». Litiyo i Metallurgiya (FOUNDRY PRODUCTION AND METALLURGY), no 1 (26 mars 2021) : 86–90. http://dx.doi.org/10.21122/1683-6065-2021-1-86-90.
Texte intégralRésumé :
A method for measuring the mass fraction of phosphorus in steels by atomic emission spectrometry with the inductively coupled plasma (AES-ICP) has been developed. Possibilities of atomic emission spectrometers of iCAP series for determination of phosphorus in steels allowing to reduce considerably duration of the analysis and to increase its profitability in comparison with chemical methods of the analysis are investigated. A method of decomposition of steel for the complete transfer of phosphorus into solution is proposed. The possibility of software spectrometers “iTeva” in the analysis by the method of relative concentrations. Calibration of the spectrometer was carried out on aqueous solutions with a known concentration of phosphorus using the method of relative concentrations. For the preparation of calibration solutions, chemically pure salt was used. The analytical line free from spectral overlays is selected. A good correlation of the calibration graph is obtained. The correctness of the determination is confirmed by the analysis of standard samples and comparison with the results of the determination in accordance with the chemical method. The developed technique is used in determining the mass fraction of phosphorus in steels. Validation of the methodology was carried out. iCAP spectrometers can be used to determine the mass fraction of phosphorus in steels.
4
Pelipasov, O. V., R. A. Lokhtin, V. A. Labusov et N. G. Pelevina. « Analytical capabilities of a «Grand» spectrometer in analysis of solutions using inductively coupled plasma ». Industrial laboratory. Diagnostics of materials 85, no 1II) (15 février 2019) : 82–85. http://dx.doi.org/10.26896/1028-6861-2019-85-1-ii-82-85.
Texte intégralRésumé :
It has been shown that «Grand» spectrometers based on a hybrid assembly of BLPP-2000 photodetector arrays produced by «VMK-Optoélektronika» can be used for atomic emission spectral analysis of solutions using inductively coupled plasma atomic emission spectroscopy (ICP-AES). For the prototype of a «Grand-ICP» spectrometer consisting of «Grand» spectrometer, microwave plasma generator, and RF (radiofrequency) generator, the following analytical characteristics were determined: element detection limit, long-term stability, linear ranges of calibration graphs for several elements, and optimal operating parameters of the microwave generator. The linear concentration range of analyte elements is 105when using a single analytical line of the element. The long-term stability is less than 2% in 6 h without using an internal standard. The detection limits are comparable to those of modern ICP spectrometers with an axial plasma survey and lie in a range of sub-microgram per liter. It has been found that the effect of superposition of the spectral lines of the plasma background, for example, OH molecular lines or others, on the analyte lines can be eliminated by subtracting the blank sample spectrum from the analyte spectrum using Atom software. The analytical characteristics of the spectrometer allow the use of the device both for developing new ICP- based systems and restoring the performance of defective ICP spectrometers.
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Fujita, J., S. Morita et M. Sakurai. « X-ray diagnostics for fusion plasmas ». Laser and Particle Beams 7, no 3 (août 1989) : 483–86. http://dx.doi.org/10.1017/s0263034600007448.
Texte intégralRésumé :
We have developed medium and high resolution X-ray crystal spectrometers for measurements of charge state distributions of impurity ions, density of suprathermal electrons and ion temperature in magnetically confined plasmas. The techniques utilizing these spectrometers are, in principle, applicable to laser produced plasmas, especially in their expanding phase. The role of X-ray spectroscopy to produce useful data for atomic physics as well as for plasma diagnostics is emphasized. A beam-line has been designed and installed to the Ultraviolet Synchrotron Radiation Facility (UVSOR) at IMS, Okazaki, for the purpose of establishing calibration techniques for optical components, detectors and spectrometers in the range from ultraviolet to soft X ray for plasma diagnostics. Characteristics of the beam and its application to the study of interaction between synchrotron radiation and hot dense plasmas are described. Synchrotron radiation can replace the dye laser which has so far been used as a light source in the laser-induced fluorescence method to obtain population density of specified levels in a plasma.
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Pelipasov, O. V., O. V. Komin, V. A. Labusov et V. A. Trunova. « Atomic emission spectrometers with nitrogen microwave plasma Grand-SVCH ». Аналитика и контроль 28, no 4 (2024) : 382–93. https://doi.org/10.15826/analitika.2024.28.4.004.
Texte intégralRésumé :
The emergence of microwave plasma sources with parameters (T, ne) close to those of inductively coupled plasma, along with the possibility of using atmospheric nitrogen (approximately 80% N2 in the atmosphere) as the plasma gas, led to the development of series microwave plasma atomic emission spectrometers. To address the need for import substitution, Russian atomic emission spectrometer Grand-SVCH (No. 89108-23 in the State Register of Measuring Instruments of the Russian Federation) was developed and launched; the purpose of this work is presenting technical features and characteristics of this instrument. A microwave resonator (2.45 GHz) incorporating a dielectric element that enables the formation of toroidal plasma close in size to that of ICP in a standard three-flow vertically installed burner was developed for generating plasma. A spectrometer, based on the Paschen-Runge design, registers the plasma spectrum simultaneously in the 190-780 nm range using BLPP-4000 detectors with a resolution of 8 pm in the 190-350 nm range and 25 pm in the 350-780 nm range. The spectrometer provides axial viewing of the plasma. Grand-SVCH spectrometer matches its foreign counterparts in analytical performance: detection limits (3σ) ≤ 1 µg/L; long-term stability, characterized by the relative standard deviation of analyte signals of less than 3 %; and a linearity range exceeding six orders of magnitude when using multiple lines and measuring the spectrum with two basic exposure times. Additionally, it offers higher speed than Agilent MP-AES 4210 due to simultaneous spectrum registration across the entire spectral range and reduced matrix effects. Grand-SVCH spectrometer was successfully tested by laboratory staff at industrial enterprises in Russia and in scientific institutes of the Siberian Branch of the Russian Academy of Sciences.
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Torrisi, Lorenzo, Giuseppe Costa, Giovanni Ceccio, Antonino Cannavò, Nancy Restuccia et Mariapompea Cutroneo. « Magnetic and electric deflector spectrometers for ion emission analysis from laser generated plasma ». EPJ Web of Conferences 167 (2018) : 03011. http://dx.doi.org/10.1051/epjconf/201816703011.
Texte intégralRésumé :
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.
8
Mustafaev, Aleksandr S., Anna N. Popova et Vladimir S. Sukhomlinov. « A New Technique of Eliminating the Actual Plasma Background When Calibrating Emission Spectrometers with a CCD Recording System ». Applied Sciences 12, no 6 (11 mars 2022) : 2896. http://dx.doi.org/10.3390/app12062896.
Texte intégralRésumé :
This research focuses on the development of a new technique of emission spectral analysis designed to accurately account for the background radiation. The technique enables the evaluation of background radiation while being unaffected by its spectral shape. This is possible through the use of standard data obtained in an analytical-line-recording process performed by light-intensity-to-electric-signal converters such as CCDs, PMTs, photodiodes, etc. This technique, when applied at a set RMS deviation of the analytical-line-radiation intensity, reduces the random error of a determined low impure-element concentration due to the optimal calibration-line slope. In areas of high concentrations, an accurate accounting of the background does little to affect the emission spectrometer’s measurement accuracy. This technique also allows the replication of calibration curves in spectrometers of the same type by a linear-intensity conversion with only two standard samples required. The technique was tested on SPAS-02 and SPAS-05 commercial spark spectrometers. The testing fully confirmed the aforementioned advantages of the developed technique. The authors also determined the applicability conditions of the conventional emission-spectrometer-recalibration method by a linear conversion of the analytical-line intensity.
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Ingham, Mark N., et Bruno A. R. Vrebos. « High Productivity Geochemical XRF Analysis ». Advances in X-ray Analysis 37 (1993) : 717–24. http://dx.doi.org/10.1154/s0376030800016281.
Texte intégralRésumé :
XRF has become over the years a method of choice when dealing with elemental analysis of large quantities of samples. Geochemical analysis pushes the technique to its limits because of the large number of samples to be analysed as well as the lower limits of detection required for many trace elements of geochemical and economic importance. The Analytical Geochemistry Group at the British Geological Survey (BGS) has access to a wide variety of methods for instrumental analysis. Instrumental methods for inorganic analysis include x-ray fluorescence as well as DC arc emission spectrometry, atomic absorption spectrometry, inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). X-ray fluorescence, however, is the technique of choice when it comes to the routine analysis of large numbers of solid samples. The XRF section at BGS currently runs three sequential spectrometers (one PW1480 and two PW2400s made by Philips Analytical X-Ray). In this paper, some aspects of the method of sample preparation and the calibration of the spectrometers for the analysis of the trace elements are discussed.
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Stakheev, A. A., et T. P. Stolboushkina. « Metal analysis in rice flour ». Journal of Physics : Conference Series 2192, no 1 (1 mars 2022) : 012027. http://dx.doi.org/10.1088/1742-6596/2192/1/012027.
Texte intégralRésumé :
Abstract The principal goal of present work was to develop a precise method of Inductively Coupled Plasma Mass Spectrometry (ICP-MS) method to measure trace toxic elements (Cd and Pb) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) method to measure macro and micro elements (K and Cu respectively) in rice flour, the sample preparation method using a system for microwave-assisted pressure digestion and the preparation of laboratory plasticware. The parameters of the sample preparation method, of the spectrometers and measurement results are given.
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Makarov, V. A., et T. K. Savosteenko. « Determination of the mass fraction of potassium and sodium oxides in the dust of electric furnace filters by atomic emission spectrometry with inductively coupled plasma ». Litiyo i Metallurgiya (FOUNDRY PRODUCTION AND METALLURGY), no 3 (20 octobre 2020) : 62–66. http://dx.doi.org/10.21122/1683-6065-2020-3-62-66.
Texte intégralRésumé :
A method of measuring the mass fraction of potassium and sodium oxides in the dust filters of electric arc furnaces by atomic emission spectrometry with the inductively coupled plasma (AES-ICP) was developed. Possibilities of atomic emission spectrometers of iCAP series for determination of potassium and sodium in dust of filters of electric arc furnaces are investigated.A method for converting potassium and sodium oxides into solution is proposed. Calibration of the spectrometer was carried out on aqueous solutions with a known concentration of potassium and sodium. For the preparation of calibration solutions, chemically pure potassium and sodium salts were used. Analytical lines of potassium and sodium free from spectral overlays are selected.A good correlation of calibration graphs is obtained. The developed technique is used to determine the mass fraction of potassium and sodium oxides in the dust filters of electric furnaces. Validation of the methodology was carried out. The repeatability of the results was compared with the repeatability of the standardized methodology. iCAP series spectrometers can be used to determine the mass of potassium and sodium oxides in gas cleaning dust.s cleaning dust.
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Islam, Md Anwarul, et Shinichi Namba. « Spectroscopic Diagnostics of Radiation Reabsorption in Dense He Arc Plasmas ». International Journal of Research and Innovation in Applied Science IX, no VII (2024) : 194–201. http://dx.doi.org/10.51584/ijrias.2024.907019.
Texte intégralRésumé :
Observing the light emission from plasmas spectroscopically allows for the determination of key plasma parameters like electron temperature, density and external field. This method, known as plasma spectroscopy, serves as a non-intrusive diagnostic tool to study plasma dynamics. However, overlooking the impact of radiation reabsorption in the typical analytic model may compromise the accuracy of observed plasma behavior. This study addresses the influence of radiation reabsorption on plasma spectroscopic diagnosis, focusing on linear divertor simulators and plasma spectrometers designed for high-density Large Helical Device (LHD) plasmas, where optical thickness cannot be disregarded. The discussion delves into understanding the effects of radiation reabsorption in these observations.
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Islam, Md Anwarul, et Shinichi Namba. « Radiation Reabsorption Using Plasma Spectroscopic Diagnostics of High Density He Arc Plasmas ». International Journal of Research and Scientific Innovation XI, no III (2024) : 683——688. http://dx.doi.org/10.51244/ijrsi.2024.1103048.
Texte intégralRésumé :
It is possible to determine the plasma parameters such as electron temperature/density and the external field by observing the light emission spectroscopically from the plasmas. The so-called plasma spectroscopy is used as one of the non-invasive plasma diagnostic methods which investigates the plasma dynamics. However, if we simply treat the effect of radiation reabsorption, which is neglected in the usual analytic model, the observed plasma may impair the understanding of this observation. It deals with the effects of radiation reabsorption on plasma spectroscopic diagnosis. The efforts will be made for linear divertor simulators and plasma spectrometers for high-density LHD plasmas where the optical thickness cannot be ignored. Thus, we discuss the influence of radiation reabsorption in the observations using He arc plasmas.
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Robinson, Carol V. « Mass spectrometry : From plasma proteins to mitochondrial membranes ». Proceedings of the National Academy of Sciences 116, no 8 (4 février 2019) : 2814–20. http://dx.doi.org/10.1073/pnas.1820450116.
Texte intégralRésumé :
In this Inaugural Article, I trace some key steps that have enabled the development of mass spectrometry for the study of intact protein complexes from a variety of cellular environments. Beginning with the preservation of the first soluble complexes from plasma, I describe our early experiments that capitalize on the heterogeneity of subunit composition during assembly and exchange reactions. During these investigations, we observed many assemblies and intermediates with different subunit stoichiometries, and were keen to ascertain whether or not their overall topology was preserved in the mass spectrometer. Adapting ion mobility and soft-landing methodologies, we showed how ring-shaped complexes could survive the phase transition. The next logical progression from soluble complexes was to membrane protein assemblies but this was not straightforward. We encountered many pitfalls along the way, largely due to the use of detergent micelles to protect and stabilize complexes. Further obstacles presented when we attempted to distinguish lipids that copurify from those that are important for function. Developing new experimental protocols, we have subsequently defined lipids that change protein conformation, mediate oligomeric states, and facilitate downstream coupling of G protein-coupled receptors. Very recently, using a radical method—ejecting protein complexes directly from native membranes into mass spectrometers—we provided insights into associations within membranes and mitochondria. Together, these developments suggest the beginnings of mass spectrometry meeting with cell biology.
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Carter, David A., Wade R. Thompson, Chad E. Taylor et Janne E. Pemberton. « Frequency/Wavelength Calibration of Multipurpose Multichannel Raman Spectrometers. Part II : Calibration Fit Considerations and Calibration Standards ». Applied Spectroscopy 49, no 11 (novembre 1995) : 1561–76. http://dx.doi.org/10.1366/0003702953965687.
Texte intégralRésumé :
Approaches for frequency/wavelength calibration of multichannel Raman spectrometers are presented. These approaches are directed towards practical use in laboratories in which multipurpose or specialized applications result in the need for frequent spectrometer calibration. These approaches are also useful when the sample type or configuration does not permit calibration by more routine methods. Guidelines are presented for effective use of polynomials commonly found in spectrometer calibration software for conversion of pixel number to either wavenumber or wavelength. Guidelines for the selection and use of Raman calibration standards are also presented. Standards currently used for calibration of Raman spectrometers are reviewed. Improved frequency data for indent' and the Ar+ plasma lines are presented, along with frequency data for two materials (imidazole and α-cyclodextrin) which are recommended for use as solid Raman standards.
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RENNER, O., I. USCHMANN et E. FÖRSTER. « Diagnostic potential of advanced X-ray spectroscopy for investigation of hot dense plasmas ». Laser and Particle Beams 22, no 1 (mars 2004) : 25–28. http://dx.doi.org/10.1017/s026303460422105x.
Texte intégralRésumé :
Modern experimental methods and instruments for X-ray spectral investigation of hot dense plasma provide complex information on environmental conditions in extreme states of matter. The basic spectroscopic conceptions for K-shell plasma diagnosis are outlined, the main characteristics of toroidally bent crystal spectrometers and vertical-dispersion instruments are briefly reviewed. Selected applications (monitoring and optimization of the emission from the femtosecond-laser-produced plasmas, characterization of colliding laser-exploded foils, spectral line merging, and continuum lowering in constrained-flow plasmas) demonstrate the usefulness of advanced spectroscopic methods for plasma diagnostics and fundamental research.
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Buckley, Brian T., Rachel Buckley et Cathleen L. Doherty. « Moving toward a Handheld “Plasma” Spectrometer for Elemental Analysis, Putting the Power of the Atom (Ion) in the Palm of Your Hand ». Molecules 26, no 16 (6 août 2021) : 4761. http://dx.doi.org/10.3390/molecules26164761.
Texte intégralRésumé :
Many of the current innovations in instrument design have been focused on making them smaller, more rugged, and eventually field transportable. The ultimate application is obvious, carrying the instrument to the field for real time sample analysis without the need for a support laboratory. Real time data are priceless when screening either biological or environmental samples, as mitigation strategies can be initiated immediately upon the discovery that contaminant metals are present in a location they were not intended to be. Additionally, smaller “handheld” instruments generally require less sample for analysis, possibly increasing sensitivity, another advantage to instrument miniaturization. While many other instruments can be made smaller just by using available micro-technologies (e.g., eNose), shrinking an ICP-MS or AES to something someone might carry in a backpack or pocket is now closer to reality than in the past, and can be traced to its origins based on a component-by-component evaluation. While the optical and mass spectrometers continue to shrink in size, the ion/excitation source remains a challenge as a tradeoff exists between excitation capabilities and the power requirements for the plasma’s generation. Other supporting elements have only recently become small enough for transport. A systematic review of both where the plasma spectrometer started and the evolution of technologies currently available may provide the roadmap necessary to miniaturize the spectrometer. We identify criteria on a component-by-component basis that need to be addressed in designing a miniaturized device and recognize components (e.g., source) that probably require further optimization. For example, the excitation/ionization source must be energetic enough to take a metal from a solid state to its ionic state. Previously, a plasma required a radio frequency generator or high-power DC source, but excitation can now be accomplished with non-thermal (cold) plasma sources. Sample introduction, for solids, liquids, and gasses, presents challenges for all sources in a field instrument. Next, the interface between source and a mass detector usually requires pressure reduction techniques to get an ion from plasma to the spectrometer. Currently, plasma mass spectrometers are field ready but not necessarily handheld. Optical emission spectrometers are already capable of getting photons to the detector but could eventually be connected to your phone. Inert plasma gas generation is close to field ready if nitrogen generators can be miniaturized. Many of these components are already commercially available or at least have been reported in the literature. Comparisons to other “handheld” elemental analysis devices that employ XRF, LIBS, and electrochemical methods (and their limitations) demonstrate that a “cold” plasma-based spectrometer can be more than competitive. Migrating the cold plasma from an emission only source to a mass spectrometer source, would allow both analyte identification and potentially source apportionment through isotopic fingerprinting, and may be the last major hurdle to overcome. Finally, we offer a possible design to aid in making the cold plasma source more applicable to a field deployment.
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Pelipasov, O. V., V. A. Labusov, D. N. Skorobogatov, M. S. Saushkin, O. V. Komin, D. O. Selunin, I. A. Zarubin, Z. V. Semenov et V. A. Trunova. « Grand-ICP Atomic emission spectrometers with argon inductively coupled plasma ». Аналитика и контроль 28, no 4 (2024) : 370–81. https://doi.org/10.15826/analitika.2024.28.4.003.
Texte intégralRésumé :
The year 2024 marks the 50th anniversary of the first commercially available argon inductively coupled plasma (ICP) atomic emission spectrometer. Since then, ICP atomic emission spectrometry has become one of the most widely used analytical methods in the world. ICP is obtained using semiconductor or vacuum tube generators with frequency of 27.12 or 40.68 MHz. The emission spectra of the analyzed solutions are recorded using spectral instruments with crossed dispersion (echelle spectrometer) with a matrix detector or with polychromators built according to the Paschen-Runge scheme, assemblies of detector lines. To solve the problem of import substitution, serial production of Russian atomic emission spectrometer Grand-ICP (No. 89108-23 in the state register of measuring instruments of the Russian Federation) has been developed and launched; and the aim of this work is presenting analytical characteristics of this instrument. ICP is obtained using a self-excited RF generator (40.68 MHz) based on a generator triode. Plasma is maintained in a vertically installed three-stream semi-dismountable quartz burner. The spectral device based on the Paschen-Runge scheme records the spectrum simultaneously in the range from 160 to 780 nm using BLPP-4000 detector arrays with the resolution of 15 pm in the range of 160–190 nm, 8 pm for 190–350 nm, and 25 pm for 350–780 nm. The spectrometer implements axial, radial and double plasma viewing. Grand-ICP spectrometer is not inferior to the foreign analogues in its analytical characteristics: elements detection limits (3σ) ≤ 1 μg/l; long-term stability of analytical signals is characterized by an RSD (relative standard deviation) of less than 2 % for analytes and less than 1 % for Ar lines; the linearity range of the calibration dependencies is more than 106 when using a double plasma viewing and more than 107 when using multiple lines. Grand-ICP spectrometer was successfully tested by employees of laboratories of industrial enterprises in the Russian Federation and in scientific institutes of the Siberian Branch of the Russian Academy of Sciences.
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Doms, Marco, et Jörg Müller. « Design, Fabrication, and Characterization of a Micro Vapor-Jet Vacuum Pump ». Journal of Fluids Engineering 129, no 10 (22 mai 2007) : 1339–45. http://dx.doi.org/10.1115/1.2776968.
Texte intégralRésumé :
A microelectromechanical system (MEMS) vapor-jet pump for vacuum generation in miniaturized analytical systems, e.g., micro-mass-spectrometers (Wapelhorst, E., Hauschild, J., and Mueller, J., 2005, “A Fully Integrated Micro Mass Spectrometer,” in Fifth Workshop on Harsh-Environment Mass Spectrometry;Hauschild, J., Wapelhorst, E., and Mueller, J., 2005, “A Fully Integrated Plasma Electron Source for Micro Mass Spectrometers,” in Ninth International Conference on Miniaturized Systems for Chemistry and Life Sciences (μTAS), pp. 476–478), is presented. A high velocity nitrogen or water vapor jet is used for vacuum generation. Starting from atmospheric pressure, a high throughput of more than 23ml∕min and an ultimate pressure of 495mbars were obtained with this new type of micropump. An approach for the full integration of all components of the pump is presented and validated by experimental results. The pump is fabricated from silicon and glass substrates using standard MEMS fabrication techniques including deep reactive ion etching, trichlorosilane molecular vapor deposition, and metal-assisted chemical etching for porous silicon fabrication. Micromachined pressure sensors based on the Pirani principle have been developed and integrated into the pump for monitoring.
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Wark, J. S. « Transient effects in laser-plasma X-ray spectrometers ». Laser and Particle Beams 9, no 2 (juin 1991) : 569–77. http://dx.doi.org/10.1017/s026303460000358x.
Texte intégralRésumé :
X-ray spectroscopy is a widely used means of diagnosing densities and temperature within laser-produced plasmas. At X-ray energies above approximately 1 keV, Bragg crystal spectrometers are routinely used to record X-ray spectra. Quantitative measurements of plasma conditions can be obtained with a knowledge of crystal reflectivity and film or detector response. In such data analysis it is always assumed that the crystal response is constant in time. However, we show that under certain adverse experimental conditions the X-ray fluxes incident on the crystal are so high as to significantly transiently modify the reflection characteristics of the crystal. Such degradation need not necessarily be accompanied by a loss of observed spectral solution. The transient (nanosecond-time-scale) change in crystal reflectivity is due to a change from dynamical to more kinematic diffraction caused by an X-ray-induced thermal strain gradient in the surface layer of the crystal. The decay time of this strain is typically several nanoseconds. Calculations of some specific crystal reflectivities and rocking curves under such conditions are presented, and methods of minimizing the effect by appropriate filtering are discussed.
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Polyakova, E. V., et O. V. Pelipasov. « Comparison of matrix effects on atomic emission spectrometers with nitrogen microwave induced plasma ». Аналитика и контроль 25, no 4 (2021) : 313–17. http://dx.doi.org/10.15826/analitika.2021.25.4.004.
Texte intégralRésumé :
The creation and implementation of new sources of sample excitation and spectrometers based on them into the practice of analytical laboratories raises many questions for researchers about the obtained analytical characteristics of new equipment and analysis methods. The most important characteristics of any method include detection limits, accuracy and reproducibility of the results obtained. Matrix elements can have a significant effect on these parameters. The paper shows a comparison of the change in the intensities of analytical lines of elements in the presence of matrix elements with ionization potentials of 5.13 - 10.48 eV (Na, Cu, Pb, Cd, Zn, In, Ga, Bi) in the concentration range of 0 - 1 wt %. on commercially available atomic emission spectrometers with microwave plasma Grand-MP ("VMK-Optoelektronika") and Agilent MP-AES 4100 (Agilent Technologies). It is shown that the magnitude of the matrix effect in these excitation sources depends on the ionization potential of the matrix element and the total energy of the analyte line. A significant effect of matrix elements with a concentration of up to 1% wt. on the intensity of spectral lines of atoms and ions of the sample. Elements with medium and high ionization energies practically do not affect the intensity of atomic spectral lines of impurity elements and lead to a decrease in the intensity of ionic lines. The influence of easily ionized elements is more pronounced - both depressing and amplifying effects are observed, probably caused by both a change in the concentration of electrons in the plasma, leading to a linear change in the equilibrium between atoms and ions, and a decrease in the plasma temperature. An increase in the power supplied to the plasma on the Grand-MP spectrometer leads to a decrease in the effect of easily ionized elements on the intensity of the spectral lines of the elements. It is shown that the plasma in the Grand-MP spectrometer has better resistance to matrix influences as compared to the Agilent MP-AES 4100, which is associated with a large plasma volume and a higher input power.
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Song, Honghu, Zhen Wu, Hui Zhang, Junli Li et Rui Qiu. « A simulation optimization design of the filter stack spectrometer for laser-plasma interaction experiment ». Journal of Instrumentation 18, no 03 (1 mars 2023) : P03012. http://dx.doi.org/10.1088/1748-0221/18/03/p03012.
Texte intégralRésumé :
Abstract Filter stack spectrometers are widely employed in laser facilities for the spectrum measurement of bremsstrahlung photons. However, this method suffers from large uncertainty of unfolding due to its intrinsic limit resolution. For this, an optimization study on filter stack spectrometer is conducted. This procedure is implemented by a hybrid particle swarm optimization and genetic algorithm (PSO-GA). Monte-Carlo particle transport code Fluka is used for the simulation of the response matrix. Gravel algorithm, based on the least-square method, is used for the unfolding. For mono-energetic photons, this optimized filter stack spectrometer design provides a better energy resolution. For continuous distribution, this optimized filter stack spectrometer design yields a narrower unfolding solution space in the presence of measurement error.
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Graf, A. T., S. Brockington, R. Horton, S. Howard, D. Hwang, P. Beiersdorfer, J. Clementson et al. « Spectroscopy on magnetically confined plasmas using electron beam ion trap spectrometers ». Canadian Journal of Physics 86, no 1 (1 janvier 2008) : 307–13. http://dx.doi.org/10.1139/p07-117.
Texte intégralRésumé :
Multiple spectrometers originally designed for and used at the University of California Lawrence Livermore National Laboratory’s electron beam ion trap have found use at various magnetically confined plasma facilities. Three examples will be described. First is a soft X-ray/EUV grating spectrometer (6–150 Å), which is operating at the National Spherical Torus Experiment. Second is an EUV spectrometer with wavelength coverage up to 400 Å, which has just recently started operating at the Sustained Spheromak Physics Experiment. The last is a high-resolution transmission-grating spectrometer for visible light that has been used at the Compact Toroid Injection Experiment and is currently at the Alcator C-Mod tokamak.PACS Nos.: 39.30.+w, 52.55.–s, 32.30.Rj, 07.60.Rd, 52.70.La
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Lapshinov, Boris A., et Nikolay I. Timchenko. « Measurement of the spatial characteristics of an erosive silicon laser plasma using small-sized high-resolution spectrometers ». Izmeritel`naya Tekhnika, no 1 (2021) : 38–42. http://dx.doi.org/10.32446/0368-1025it.2021-1-38-42.
Texte intégralRésumé :
The spatial characteristics of the erosion laser plasma are investigated. The application of small-sized spectrometers of the visible and ultraviolet ranges for recording the spectrum of plasma radiation is considered. Erosive laser plasma is formed on the surface of a silicon target under the action of pulsed laser radiation with a wavelength of 1064 nm under normal atmospheric conditions. The laser plasma torch was scanned using a movable slit diaphragm oriented parallel to the target surface. The emission of erosion laser plasma was recorded using small-size spectrometers. Based on the obtained plasma emission spectra, the dependences of the intensity of the spectral lines of silicon on the geometric position of the slit diaphragm are revealed. A comparison is made of the intensities of the spectral lines of silicon on the polished and grinded sides of the target.
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Yi, Shengzhen, Huiyao Du, Haoxuan Si, Yue Yu, Jun Xiong et Zhanshan Wang. « A Wide-Range High-Resolution X-ray Crystal Spectrometer for Laser–Plasma Diagnostics ». Photonics 10, no 9 (15 septembre 2023) : 1054. http://dx.doi.org/10.3390/photonics10091054.
Texte intégralRésumé :
Wide-range crystal spectrometers are important tools for performing X-ray spectroscopic measurements of medium- and high-Z tracer elements in research on laser-driven inertial confinement fusion (ICF) plasmas. In this paper, we propose a wide-range high-resolution crystal spectrometer based on a tandem array of crystals that have the same geometric parameters. We have developed a three-channel crystal spectrometer that covers the range of 8–18 keV by combining Ge<311>, Ge<331>, and Ge<531> crystals. Here, we report the design, optical simulations, and X-ray test experiments of this spectrometer. The calibration results indicate that the spectral resolution E/ΔE is greater than 2800 at 8.048 keV. By selecting appropriate Bragg angles, crystal materials, orientations, or other geometrical parameters, the wide-range crystal spectrometer developed in this paper can also be used to make measurements in other energy ranges.
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Lucchi, John, Mauro Martinez et Matthieu Baudelet. « Homogenization of Plasma Emission Collection for Multichannel Spectrometers ». Applied Spectroscopy 73, no 10 (20 juin 2019) : 1228–36. http://dx.doi.org/10.1177/0003702819843992.
Texte intégralRésumé :
Laser-induced breakdown spectroscopy (LIBS) has recently demonstrated its unrivaled performance for broadband elemental imaging of surfaces. The dimensions of the laser sampling spot still being potentially larger than the interfaces of chemical domains, the plasma created at each location can be largely varying and inhomogeneous with contributions from the different sides of the interface. This variation can become problematic when imaging it on fiber bundles connected to multiple spectrometers. A spatially heterogeneous signal would lead to spatially dependent image on the fiber bundle causing inconsistent readings and loss of efficiency. Köhler illumination is used in this study to create a homogenous illumination, regardless of the source homogeneity, thus improving light collection efficiency. The performance of this approach was demonstrated with inhomogeneous spectral sources and applied to the LIBS analysis of a metallic interface, showing up to a sixfold improvement of the homogeneity of the plasma collection.
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Pupyshev, A. A. « Spectral interferences and their correction in atomic emission spectral analysis ». Industrial laboratory. Diagnostics of materials 85, no 1II) (15 février 2019) : 15–32. http://dx.doi.org/10.26896/1028-6861-2019-85-1-ii-15-32.
Texte intégralRésumé :
The main sources of spectral interferences in atomic emission spectral analysis (AESA) are considered, including both wide-range (bremsstrahlung and recombination continuum, radiation of hot condensed particles and electrode ends, scattered light in the spectrometer, overlapping of the analytical line by the wings of the neighbor strong spectral lines of interfering elements, imposition of the components of molecular bands with the very close lines) and narrow-band (partial or complete overlapping of the analytical line with atomic or ionic lines of the sample elements, electrodes and discharge atmosphere; superposition of spectra from higher orders of reflection in conventional diffraction spectrometers and from neighboring orders in two-dimensional echelle spectrometers). The features of their manifestation in various sources of spectrum excitation (flames, DC arc, spark discharges, arc plasma discharges, inductively coupled plasma, microwave plasma, low-pressure electric discharges, laser spark) are considered. The possibilities of reducing the level of spectral interferences or elimination of the spectral noise at the stage of design and manufacturing of AESA devices, as well as upon selecting and adjusting of operation conditions of the analysis are shown. Much attention is paid to the most easily implemented in practice off-peak correction of wide-range spectral interferences. The modern methods of background correction under the spectral peak (under-peak) using a software for atomic emission spectrometers and providing creation of various mathematical models of the background signal in the vicinity of the analytical line at the stage of developing a specific AESA technique are considered. The issues of the choice of spectral lines for analytical measurements, tables and atlases of spectral lines, electronic databases used for this purpose are considered in detail. Specific features of application of the method of inter-element correction with direct spectral overlapping of the lines are given. The operating sequence for taking into account spectral interferences when developing the analysis techniques is proposed.
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Tamagawa, T., Y. Hironaka, K. Kawasaki, D. Tanaka, T. Idesaka, N. Ozaki, R. Kodama et al. « Development of an experimental platform for the investigation of laser–plasma interaction in conditions relevant to shock ignition regime ». Review of Scientific Instruments 93, no 6 (1 juin 2022) : 063505. http://dx.doi.org/10.1063/5.0089969.
Texte intégralRésumé :
The shock ignition (SI) approach to inertial confinement fusion is a promising scheme for achieving energy production by nuclear fusion. SI relies on using a high intensity laser pulse (≈1016 W/cm2, with a duration of several hundred ps) at the end of the fuel compression stage. However, during laser–plasma interaction (LPI), several parametric instabilities, such as stimulated Raman scattering and two plasmon decay, nonlinearly generate hot electrons (HEs). The whole behavior of HE under SI conditions, including their generation, transport, and final absorption, is still unclear and needs further experimental investigation. This paper focuses on the development of an experimental platform for SI-related experiments, which simultaneously makes use of multiple diagnostics to characterize LPI and HE generation, transport, and energy deposition. Such diagnostics include optical spectrometers, streaked optical shadowgraph, an x-ray pinhole camera, a two-dimensional x-ray imager, a Cu Kα line spectrometer, two hot-electron spectrometers, a hard x-ray (bremsstrahlung) detector, and a streaked optical pyrometer. Diagnostics successfully operated simultaneously in single-shot mode, revealing the features of HEs under SI-relevant conditions.
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Vaisberg, O. L., et S. D. Shuvalov. « New Spectrometer ULTIMAN for Space Plasma Research ». Астрономический вестник 57, no 3 (1 mai 2023) : 284–92. http://dx.doi.org/10.31857/s0320930x23030106.
Texte intégralRésumé :
Measurements of ion velocity distributions are one of basic goals of space plasma studies. There is variety of ion and electron spectrometers (see, for example, Wüest et al., 2007; Young et al., 2007; Zurbuchen and Gershman, 2016; Vaisberg et al., 2016). The most commonly used ion spectrometer is the top-hat analyzer (Carlson et al., 1983) consisting of a toroidal electrostatic analyzer, an electrostatic scanner, and a timeof-flight section with thin foil as a start element and ion preacceleration. We describe a new energy-mass analyzer with an electrostatic scanner providing a hemispheric field of view with small aberration, a toroidal electrostatic analyzer, and a time-of-flight synchronizer with a simple gate. It provides desirable hemisphere scanning, wide energy range, and reasonable mass resolution to meet most space exploration challenges. It can provide detailed measurements of the ion velocity distribution of ion species without significant gaps to obtain the structure of the hot plasma flow. With simple electrooptics elements this analyzer can be easily modified for many plasma research purposes.
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Mouikis, C. G., L. M. Kistler, G. Wang et Y. Liu. « Background subtraction for the Cluster/CODIF plasma ion mass spectrometer ». Geoscientific Instrumentation, Methods and Data Systems 3, no 1 (16 avril 2014) : 41–48. http://dx.doi.org/10.5194/gi-3-41-2014.
Texte intégralRésumé :
Abstract. The CODIF instrument on the Cluster spacecraft is a time-of-flight (TOF) ion mass spectrometer. Although TOF spectrometers are relatively immune to background contamination due to the inherent double coincidence requirement, high background rates can still result in false coincidences. Along the Cluster orbit, false coincidences are commonly observed due to the penetrating radiation of relativistic electrons during the encounters with the Earth's radiation belts. A second type of background in these instruments occurs when events of one species fall into the time-of-flight range defined for another species. Although the fraction of the H+ events that spill into the He+ measurement is small, when the actual He+ fluxes are low this can result in significant contamination. In this paper we present two techniques that allow the subtraction of the false coincidences and the H+ "spill" from the CODIF measurements.
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Mouikis, C. G., L. M. Kistler, G. Wang et Y. Liu. « Background subtraction for the Cluster/CODIF plasma ion mass spectrometer ». Geoscientific Instrumentation, Methods and Data Systems Discussions 3, no 2 (27 septembre 2013) : 567–89. http://dx.doi.org/10.5194/gid-3-567-2013.
Texte intégralRésumé :
Abstract. The CODIF instrument on the Cluster spacecraft is a time-of-flight (TOF) ion mass spectrometer. Although TOF spectrometers are relatively immune to background contamination due to the double coincidence requirement, high background rates can still result in false coincidences. Along the Cluster orbit, false coincidences are commonly observed due to the penetrating radiation of relativistic electrons during the encounters with the Earth's radiation belts. A second type of background in these instruments occurs when events of one species fall into the time-of-flight range defined for another species. Although the fraction of the H+ events that spill into the He+ measurement is small, when the actual He+ fluxes are low this can result in significant contamination. In this paper we present two techniques that allow the subtraction of the false coincidences and the H+ "spill" from the CODIF measurements.
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Costa, Giuseppe, et Lorenzo Torrisi. « Diagnostics of Particles emitted from a Laser generated Plasma : Experimental Data and Simulations ». EPJ Web of Conferences 167 (2018) : 04005. http://dx.doi.org/10.1051/epjconf/201816704005.
Texte intégralRésumé :
The charge particle emission form laser-generated plasma was studied experimentally and theoretically using the COMSOL simulation code. The particle acceleration was investigated using two lasers at two different regimes. A Nd:YAG laser, with 3 ns pulse duration and 1010 W/cm2 intensity, when focused on solid target produces a non-equilibrium plasma with average temperature of about 30-50 eV. An Iodine laser with 300 ps pulse duration and 1016 W/cm2 intensity produces plasmas with average temperatures of the order of tens keV. In both cases charge separation occurs and ions and electrons are accelerated at energies of the order of 200 eV and 1 MeV per charge state in the two cases, respectively. The simulation program permits to plot the charge particle trajectories from plasma source in vacuum indicating how they can be deflected by magnetic and electrical fields. The simulation code can be employed to realize suitable permanent magnets and solenoids to deflect ions toward a secondary target or detectors, to focalize ions and electrons, to realize electron traps able to provide significant ion acceleration and to realize efficient spectrometers. In particular it was applied to the study two Thomson parabola spectrometers able to detect ions at low and at high laser intensities. The comparisons between measurements and simulation is presented and discussed.
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Thorn, D. B., F. Coppari, T. Döppner, M. J. MacDonald, S. P. Regan et M. B. Schneider. « X-ray spectrometer throughput model for (selected) flat Bragg crystal spectrometers on laser plasma facilities ». Review of Scientific Instruments 89, no 10 (octobre 2018) : 10F119. http://dx.doi.org/10.1063/1.5039423.
Texte intégral
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Zhou, Yugang, Sixin Wu, Qiang Li, Qiang Yang, Jiaxing Wen, Yue Yang, Wenbo Mo, Lushan Wang, Ling miao et Jiazhou Li. « Experimental verification for optimal design of the filter-based spectrometer ». Journal of Instrumentation 19, no 11 (1 novembre 2024) : P11023. http://dx.doi.org/10.1088/1748-0221/19/11/p11023.
Texte intégralRésumé :
Abstract Filter-based spectrometers are widely used in the diagnostics of laser-plasma-generated X/gamma-ray pulses. The highly ill-conditioned characteristic of the filter-based spectrometer response matrix is a primary factor limiting their measurement accuracy. In this paper, the genetic algorithm is used to optimize the configuration of the filter-based spectrometer to alleviate the ill-conditioned response. The effectiveness of optimization was investigated under different conditions such as different measurement errors, different spectrum shapes and different unfolding algorithms by numerical experiment. Furthermore, the optimized and non-optimized filter stack spectrometer were implemented and irradiated by X-ray tubes. These results show that the optimization can effectively reduce the divergence of the unfolded spectrum for continuous spectrum X-ray detection and improve peak unfolding accuracy for monochromatic X-ray detection.
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Shin, Hyunjin, Miray Mutlu, John M. Koomen et Mia K. Markey. « Parametric Power Spectral Density Analysis of Noise from Instrumentation in MALDI TOF Mass Spectrometry ». Cancer Informatics 3 (janvier 2007) : 117693510700300. http://dx.doi.org/10.1177/117693510700300019.
Texte intégralRésumé :
Noise in mass spectrometry can interfere with identification of the biochemical substances in the sample. For example, the electric motors and circuits inside the mass spectrometer or in nearby equipment generate random noise that may distort the true shape of mass spectra. This paper presents a stochastic signal processing approach to analyzing noise from electrical noise sources (i.e., noise from instrumentation) in MALDI TOF mass spectrometry. Noise from instrumentation was hypothesized to be a mixture of thermal noise, 1/f noise, and electric or magnetic interference in the instrument. Parametric power spectral density estimation was conducted to derive the power distribution of noise from instrumentation with respect to frequencies. As expected, the experimental results show that noise from instrumentation contains 1/f noise and prominent periodic components in addition to thermal noise. These periodic components imply that the mass spectrometers used in this study may not be completely shielded from the internal or external electrical noise sources. However, according to a simulation study of human plasma mass spectra, noise from instrumentation does not seem to affect mass spectra significantly. In conclusion, analysis of noise from instrumentation using stochastic signal processing here provides an intuitive perspective on how to quantify noise in mass spectrometry through spectral modeling.
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Deprince, J., M. A. Bautista, S. Fritzsche, J. A. García, T. R. Kallman, C. Mendoza, P. Palmeri et P. Quinet. « Plasma-environment effects on K lines of astrophysical interest ». Astronomy & ; Astrophysics 635 (mars 2020) : A70. http://dx.doi.org/10.1051/0004-6361/201937088.
Texte intégralRésumé :
Aims. In the context of black-hole accretion disks, we aim to compute the plasma-environment effects on the atomic parameters used to model the decay of K-vacancy states in moderately charged iron ions, namely Fe IX – Fe XVI. Methods. We used the fully relativistic multiconfiguration Dirac–Fock method approximating the plasma electron–nucleus and electron–electron screenings with a time-averaged Debye–Hückel potential. Results. We report modified ionization potentials, K-threshold energies, wavelengths, radiative emission rates, and Auger widths for plasmas characterized by electron temperatures and densities in the ranges 105−107 K and 1018−1022 cm−3. Conclusions. This study confirms that the high-resolution X-ray spectrometers onboard the future XRISM and Athena space missions will be capable of detecting the lowering of the K edges of these ions due to the extreme plasma conditions occurring in accretion disks around compact objects.
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Naselli, Eugenia, David Mascali, Claudia Caliri, Giuseppe Castro, Luigi Celona, Alessio Galatá, Santo Gammino et al. « Nuclear β-decays in plasmas : how to correlate plasma density and temperature to the activity ». EPJ Web of Conferences 227 (2020) : 02006. http://dx.doi.org/10.1051/epjconf/202022702006.
Texte intégralRésumé :
Magnetized plasmas in compact traps may become experimental en-vironments for the investigation of nuclear beta-decays of astrophysical inter-est. In the framework of the project PANDORA (Plasmas for Astrophysics, Nuclear Decays Observation and Radiation for Archaeometry) the research ac-tivities are devoted to demonstrate the feasibility of an experiment aiming atmeasuring lifetimes of radionuclides of astrophysical interest when changing the charge state distribution of the in-plasma ions and the other plasma param- eters such as density and temperature. This contribution describes the multidi-agnostics setup now available at INFN-LNS, which allows unprecedented in-vestigations of magnetoplasmas properties in terms of density, temperature and charge state distribution (CSD). The setup includes an interfero-polarimeter for total plasma density measurement, a multi-X-ray detectors system for X-ray spectroscopy (including time resolved spectroscopy), an X-ray pin-hole camera for high-resolution 2D space resolved spectroscopy, a two-pin plasma-chamber immersed antenna for the detection of plasma radio-self-emission, and differ- ent spectrometers for the plasma-emitted visible light characterization. The setup is also suitable for other studies of astrophysical interest, such as turbulent plasma regimes dominated by the so-called Cyclotron Maser Instability, which is a typical kinetic turbulence occurring in astrophysical objects like magnetized stars, brown dwarfs, etc. A description of recent results about plasma parame- ters characterization in quiescent and turbulent Electron Cyclotron Resonance-heated plasmas will be given.
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Velásquez-García, Luis Fernando, Javier Izquierdo-Reyes et Hyeonseok Kim. « Review of in-space plasma diagnostics for studying the Earth’s ionosphere ». Journal of Physics D : Applied Physics 55, no 26 (28 février 2022) : 263001. http://dx.doi.org/10.1088/1361-6463/ac520a.
Texte intégralRésumé :
Abstract This review details the state of the art in in-space plasma diagnostics for characterizing the Earth’s ionosphere. The review provides a historical perspective, focusing on the last 20 years and on eight of the most commonly used plasma sensors—most of them for in situ probing, many of them with completed/in-progress space missions: (a) Langmuir probes, (b) retarding potential analysers, (c) ion drift meters, (d) Faraday cups, (e) integrated miniaturized electrostatic analysers, (f) multipole resonance probes, (g) Fourier transform infrared spectrometers, and (h) ultraviolet absorption spectrometers. For each sensor, the review covers (a) a succinct description of its principle of operation, (b) highlights of the reported hardware flown/planned to fly in a satellite or that could be put in a CubeSat given that is miniaturized, and (c) a brief description of the space missions that have utilized such sensor and their findings. Finally, the review suggests tentative directions for future research.
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Wraback, E. M., E. Landi et W. B. Manchester. « Time-dependent Hinode/EIS Atlas of a Coronal Mass Ejection Containing Cool Material ». Astrophysical Journal 970, no 2 (31 juillet 2024) : 182. http://dx.doi.org/10.3847/1538-4357/ad625f.
Texte intégralRésumé :
Abstract We report the first time-dependent spectral atlas of a coronal mass ejection (CME) observed by the Hinode/Extreme Ultraviolet Imaging Spectrometer (EIS). EIS observed the Cartwheel CME on 2008 April 9 at 09:30–10:00 UT in its full wavelength range and captured the bright core containing prominence material as it passed across the slit field of view. The measurement of the differential emission measure (DEM) showed that the observation captured two plasma components, a coronal component at Log T ≈ 6.05 K and a cold component at Log T ≈ 5.30 K, which we interpret as the prominence material in the CME core. We used this DEM to develop a spectral atlas for the four EIS spectra containing the CME material and the pre- and postevent spectra. These observations provide the basis for studying CME plasma evolution in the low solar corona, as well as guide observations from the current and upcoming spectrometers, including Solar Orbiter/SPICE, Solar-C/EUVST, and MUSE, which will advance our understanding of CME plasma evolution.
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Craciun, Cristina, Silviu Daniel Stoica, Bogdana Maria Mitu, Tomy Acsente et Gheorghe Dinescu. « Mass Spectra Fitting as Diagnostic Tool for Magnetron Plasmas Generated in Ar and Ar/H Gases with Tungsten Targets ». Molecules 28, no 15 (26 juillet 2023) : 5664. http://dx.doi.org/10.3390/molecules28155664.
Texte intégralRésumé :
In this work, we describe an ion mass spectra processing method from plasmas generated in Ar and Ar/H2 gases in contact with tungsten surfaces. For this purpose, advanced model functions, i.e., those suitable for fitting the experimental mass peak profiles, are used. In addition, the peak positions, peak shapes, abundances, and ion ratios are the parameters considered for building these functions. In the case of a multielement magnetron target, the calibration of the mass spectra with respect to the peak shape and position on the m/z scale is helpful in reducing the number of free variables during fitting. The mass spectra fitting procedure is validated by the obtained isotopic abundances of W ions in W/Ar magnetron plasmas, which, in turn, are comparable with their natural abundance. Moreover, its usefulness is exemplified by calculating the ratio of WH+/W+ ions in W/Ar/H2 plasma. This work paves the way for obtaining relevant results regarding ion species in plasma even in the case of using general-purpose mass spectrometers with limited resolution and accuracy. Although this method is illustrated for the W/Ar/H2 plasma system, it can be easily extendable to any plasma type.
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Tsikas, Dimitrios. « Perspectives of Quantitative GC-MS, LC-MS, and ICP-MS in the Clinical Medicine Science—The Role of Analytical Chemistry ». Journal of Clinical Medicine 13, no 23 (29 novembre 2024) : 7276. https://doi.org/10.3390/jcm13237276.
Texte intégralRésumé :
Mass spectrometry (MS) is the only instrumental analytical technology that utilizes unique properties of matter, that is, its mass (m) and electrical charge (z). In the magnetic and/or electric fields of mass spectrometers, electrically charged native or chemically modified (millions) endogenous and (thousands) exogenous substances, the analytes, are separated according to their characteristic mass-to-charge ratio (m/z) values. Mass spectrometers coupled to gas chromatographs (GC) or liquid chromatographs (LC), the so-called hyphenated techniques, i.e., GC-MS and LC-MS, respectively, enable reliable determination of the concentration of analytes in complex biological samples such as plasma, serum, and urine. A particular technology is represented by inductively coupled plasma-mass spectrometry (ICP-MS), which is mainly used for the analysis of metal ions. The highest analytical accuracy is reached by using mass spectrometers with high mass resolution (HR) or by tandem mass spectrometers, as it can be realized with quadrupole-type instruments, such as GC-MS/MS and LC-MS/MS, in combination with stable-isotope labeled analytes that serve as internal standards, like a standard weight in scales. GC-MS belongs to the oldest and most advanced instrumental analytical technology. From the very beginning, GC-MS found broad application in basic and applied research sciences. GC-MS has played important roles in discovering biochemical pathways, exploring underlying mechanisms of disease, and establishing new evidence-based pharmacological therapy. In this article, we make an inventory of the use of instrumental mass spectrometry in the life sciences and attempt to provide a perspective study on the future of analytical mass spectrometry in clinical science, mainly focusing on GC-MS and LC-MS. We used information freely available in the scientific database PubMed (retrieved in August–November 2024). Specific search terms such as GC-MS (103,000 articles), LC-MS (113,000 articles), and ICP-MS (14,000 articles) were used in the Title/Abstract in the “PubMed Advanced Search Builder” including filters such as search period (1970–2024). In total, around 103,000 articles on GC-MS, 113,000 articles on LC-MS (113,000), and 14,000 articles on ICP-MS were found. In the period 1995–2023, the yearly publication rate accounted for 3042 for GC-MS articles and 3908 for LC-MS articles (LC-MS/GC-MS ratio, 1.3:1). Our study reveals that GC-MS/MS, LC-MS/MS, and their high-resolution variants are indispensable instrumentations in clinical science including clinical pharmacology, internal and forensic medicine, and doping control. Long-tradition manufacturers of analytical instruments continue to provide increasingly customer-friendly GC-MS and LC-MS apparatus, enabling fulfillment of current requirements and needs in the life sciences. Quantitative GC-MS and GC-MS/MS methods are expected to be used worldwide hand in hand with LC-MS/MS, with ICP-MS closing the gap left for metal ions. The significance of analytical chemistry in clinical science in academia and industry is essential.
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Fulton, Greg, et Gary Horlick. « Aotfs as Atomic Spectrometers : Basic Characteristics ». Applied Spectroscopy 50, no 7 (juillet 1996) : 885–92. http://dx.doi.org/10.1366/0003702963905475.
Texte intégralRésumé :
An electronic spectrometer based on an acousto-optic tunable filter (AOTF) is presented. These devices are electronically tunable, narrow-band light filters with no moving parts. The wavelength range from 350 to 600 nm can be covered with a single device, the entire spectrum is scanned in less than 1 s, and any wavelength can be randomly accessed in 0.1 ms. The resolution [full width at half-height (FWHH)] was determined to be 0.22 nm at 361 nm, and the standard deviation of peak position was usually less than 0.03 nm. Under software control, the AOTF can be stationary on a line, peak-hop between any 20 different lines, hop between 20 regions of any size, scan a spectrum, or operate as a wavelength modulation spectrometer. Operation of the spectrometer is illustrated by using hollow cathode and inductively coupled plasma atomic emission sources.
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Marcer, G., M. Nocente, L. Giacomelli, G. Gorini, E. Perelli Cippo, O. Putignano, M. Rebai et al. « Study of a single line of sight gamma ray diagnostics for measurements of the absolute gamma ray emission from JET ». Journal of Instrumentation 16, no 12 (1 décembre 2021) : C12019. http://dx.doi.org/10.1088/1748-0221/16/12/c12019.
Texte intégralRésumé :
Abstract The fusion power produced in a DT thermonuclear reactor is currently determined by measuring the absolute 14 MeV neutron yield of the D(T, α)n fusion reaction. Measurements of 17 MeV gamma rays born from the much less probable D(T, 5He)γ reaction (branching ratio of ∼10−5) have been proposed as an alternative independent method to validate the neutron counting method and also to fulfill the requests of the nuclear regulator for licensing ITER DT operations. However, the development of absolute 17 MeV gamma ray emission measurements entails a number of requirements, such as: (i) knowledge of the 17 MeV gamma ray to 14 MeV neutron emission branching ratio; (ii) the simulation of the gamma ray transport from the extended plasma source to the gamma ray detectors; (iii) a careful determination of the absolute efficiency of previously calibrated gamma ray spectrometers. In this work, we have studied the possibility to infer the global gamma ray emission rate from measurements made with a 3″ × 6″ LaBr3 spectrometer installed at the end of a collimated tangential line of sight at the JET tokamak and using the neutron emission from deuterium plasmas of the most recent experimental campaigns. Results show that 17 MeV gamma ray fluxes at the end of this tangential line of sight have a weak dependence (less than 5%) on the plasma profile and can therefore be used to infer the total emission from the plasma.
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Kaczmarek, Michał, Nanyun Zhang, Ludmila Buzhansky, Sharon Gilead et Ehud Gazit. « Optimization Strategies for Mass Spectrometry-Based Untargeted Metabolomics Analysis of Small Polar Molecules in Human Plasma ». Metabolites 13, no 8 (7 août 2023) : 923. http://dx.doi.org/10.3390/metabo13080923.
Texte intégralRésumé :
The untargeted approach to mass spectrometry-based metabolomics has a wide potential to investigate health and disease states, identify new biomarkers for diseases, and elucidate metabolic pathways. All this holds great promise for many applications in biological and chemical research. However, the complexity of instrumental parameters on advanced hybrid mass spectrometers can make the optimization of the analytical method immensely challenging. Here, we report a strategy to optimize the selected settings of a hydrophilic interaction liquid chromatography-tandem mass spectrometry method for untargeted metabolomics studies of human plasma, as a sample matrix. Specifically, we evaluated the effects of the reconstitution solvent in the sample preparation procedure, the injection volume employed, and different mass spectrometry-related operating parameters including mass range, the number of data-dependent fragmentation scans, collision energy mode, duration of dynamic exclusion time, and mass resolution settings on the metabolomics data quality and output. This study highlights key instrumental variables influencing the detection of metabolites along with suggested settings for the IQ-X tribrid system and proposes a new methodological framework to ensure increased metabolome coverage.
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García-Rojas, Nancy Shyrley, Héctor Guillén-Alonso, Sandra Martínez-Jarquín, Abigail Moreno-Pedraza, Leonardo D. Soto-Rodríguez et Robert Winkler. « Build, Share and Remix : 3D Printing for Speeding Up the Innovation Cycles in Ambient Ionisation Mass Spectrometry (AIMS) ». Metabolites 12, no 2 (17 février 2022) : 185. http://dx.doi.org/10.3390/metabo12020185.
Texte intégralRésumé :
Ambient ionisation mass spectrometry (AIMS) enables studying biological systems in their native state and direct high-throughput analyses. The ionisation occurs in the physical conditions of the surrounding environment. Simple spray or plasma-based AIMS devices allow the desorption and ionisation of molecules from solid, liquid and gaseous samples. 3D printing helps to implement new ideas and concepts in AIMS quickly. Here, we present examples of 3D printed AIMS sources and devices for ion transfer and manipulation. Further, we show the use of 3D printer parts for building custom AIMS sampling robots and imaging systems. Using 3D printing technology allows upgrading existing mass spectrometers with relatively low cost and effort.
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Spagnesi, Azzurra, Daniele Zannoni, Elena Barbaro, Matteo Feltracco, Federico Dallo, Fabrizio de Blasi, Agnese Petteni et al. « Review of recent advances in Continuous Flow Analysis (CFA) technique for polar and alpine ice cores ». Annals of Geophysics 67 (17 octobre 2024) : GC442. http://dx.doi.org/10.4401/ag-9131.
Texte intégralRésumé :
Continuous Flow Analysis (CFA) systems, originally designed for field analyses of trace chemical species in ice cores, have seen significant innovations over the past decade, particularly through the integration of new spectrometric (Inductively Coupled Plasma Mass Spectrometers, Laser Absorption Spectrometers) and chromatographic techniques (Ionic Chromatography, Gas Chromatography and Liquid Chromatography). This paper reviews recent technical and methodological advances in CFA adopted by leading laboratories worldwide for the high-resolution detection of trace elements, major ions, isotopic and gaseous species in polar and alpine ice cores, exploring the strengths and limitations of different couplings, and discussing potential future enhancements.
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Huang, Chao, Yue-Heng Yang, Jin-Hui Yang et Lie-Wen Xie. « In situ simultaneous measurement of Rb–Sr/Sm–Nd or Sm–Nd/Lu–Hf isotopes in natural minerals using laser ablation multi-collector ICP-MS ». Journal of Analytical Atomic Spectrometry 30, no 4 (2015) : 994–1000. http://dx.doi.org/10.1039/c4ja00449c.
Texte intégralRésumé :
This study presents a combined methodology of simultaneously measuring Rb–Sr/Sm–Nd or Sm–Nd/Lu–Hf isotopes in natural minerals by a means of two multiple collector inductively coupled plasma mass spectrometers connected to a 193 nm excimer laser ablation system.
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Shende, Chetan, Carl Brouillette et Stuart Farquharson. « Detection of codeine and fentanyl in saliva, blood plasma and whole blood in 5-minutes using a SERS flow-separation strip ». Analyst 144, no 18 (2019) : 5449–54. http://dx.doi.org/10.1039/c9an01087d.
Texte intégralRésumé :
A rudimentary flow strip, based on SERS, was developed and used to measure drugs, such as fentanyl, in saliva, plasma, and blood. Fully developed, the strip could be used with hand-held Raman spectrometers as a simple, point-of-care drug analyzer.
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Kujirai, Osamu, Kei Yamada, Muneyuki Kohri et Haruno Okochi. « Analysis of Heat-Resistant Alloys by Inductively Coupled Plasma/Atomic Emission Spectrometry with Hydrofluoric Acid-Resistant Sample Introduction Systems ». Applied Spectroscopy 40, no 7 (septembre 1986) : 962–68. http://dx.doi.org/10.1366/0003702864508016.
Texte intégralRésumé :
A simple and fast analytical method for complex Ni-based and Co-based heat-resistant alloys has been developed by inductively coupled plasma/atomic emission spectrometry (ICP-AES). Heat-resistant alloys of widely varying composition are dissolved in a mixture of hydrofluoric acid and nitric acid. A demountable hydrofluoric acid-resistant sample introduction system was used in which the surface of polytetrafluoroethylene (PTFE) parts was treated with metallic Na to improve the wetting property of the PTFE. Synthetic standard solutions are used for the calibration. Major and minor alloying elements are determined. The calibration curve method and internal standard method are compared. The internal standard method used two spectrometers and Mg as an internal standard element.
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GUS'KOV, S. Yu, Yu S. KAS'ANOV, M. O. KOSHEVOI, V. B. ROZANOV, A. A. RUPASOV et A. S. SHIKANOV. « Scattering and transmission of laser radiation at the heating of low-density foam targets ». Laser and Particle Beams 17, no 2 (avril 1999) : 287–91. http://dx.doi.org/10.1017/s0263034699172148.
Texte intégralRésumé :
Experimental study of the radiation scattered at the laser heating of low-density foam targets and transmitted through the targets is presented. The scattered and transmitted radiations were investigated using spectrometers and streak cameras providing spatial, angular, spectral and temporal resolutions that enabled us to study the dynamics of the process of burning-through of the thick foam targets, the velocities of the plasma critical density motion as well as mass velocity of the plasma.