Journal articles: 'High ionized ion'

1

Zheng, Xing Rong, Li Shuai Guo, Yao Wen Zhang, Ji Hai Lei, and Yan Zhang Wang. "Statistical Mechanics Model of Fully Ionized Hydrogen Plasma under High Temperatures and High Pressures." Applied Mechanics and Materials 602-605 (August 2014): 3755–60. http://dx.doi.org/10.4028/www.scientific.net/amm.602-605.3755.

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Hydrogen occurs ionization under high temperatures and high pressures. Considered the interaction between the electrons and ions of fully ionized hydrogen plasma, and the translational motion of hydrogen ion obey Boltzmann distribution, Coulomb interactions between charged particles can be used Hartree-Fock integrals and described by approximants, and obtained the statistical mechanics model and equation of state of full ionized hydrogen plasma.

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Furutani, Yoichiro, Minoru Shigesada, and Hiroo Totsuji. "Effective Potential of a Partially Ionized High-Z Ion." Journal of the Physical Society of Japan 55, no. 8 (August 15, 1986): 2653–70. http://dx.doi.org/10.1143/jpsj.55.2653.

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Jen, Coty N., Jun Zhao, Peter H. McMurry, and David R. Hanson. "Chemical ionization of clusters formed from sulfuric acid and dimethylamine or diamines." Atmospheric Chemistry and Physics 16, no. 19 (October 7, 2016): 12513–29. http://dx.doi.org/10.5194/acp-16-12513-2016.

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Abstract. Chemical ionization (CI) mass spectrometers are used to study atmospheric nucleation by detecting clusters produced by reactions of sulfuric acid and various basic gases. These instruments typically use nitrate to deprotonate and thus chemically ionize the clusters. In this study, we compare cluster concentrations measured using either nitrate or acetate. Clusters were formed in a flow reactor from vapors of sulfuric acid and dimethylamine, ethylene diamine, tetramethylethylene diamine, or butanediamine (also known as putrescine). These comparisons show that nitrate is unable to chemically ionize clusters with high base content. In addition, we vary the ion–molecule reaction time to probe ion processes which include proton-transfer, ion–molecule clustering, and decomposition of ions. Ion decomposition upon deprotonation by acetate/nitrate was observed. More studies are needed to quantify to what extent ion decomposition affects observed cluster content and concentrations, especially those chemically ionized with acetate since it deprotonates more types of clusters than nitrate.Model calculations of the neutral and ion cluster formation pathways are also presented to better identify the cluster types that are not efficiently deprotonated by nitrate. Comparison of model and measured clusters indicate that sulfuric acid dimers with two diamines and sulfuric acid trimers with two or more base molecules are not efficiently chemical ionized by nitrate. We conclude that acetate CI provides better information on cluster abundancies and their base content than nitrate CI.

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Furutani, Y., H. Totsuji, K. Mima, and H. Takabe. "Internal structure of a partially ionized heavy ion. Isolated ion model." Laser and Particle Beams 7, no. 3 (August 1989): 581–88. http://dx.doi.org/10.1017/s0263034600007552.

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An effective potential and an associated electron density in a partially ionized high-Z ion are evaluated within the framework of the Thomas–Fermi–Dirac–Weizsäcker statistical model of atoms. The results are then injected as an initial input into the one-electron Schrödinger equation, a procedure based on the density functional theory. The self-consistency between the two approaches is examined. For a partially ionized ion at zero and finite temperatures, a number of bound electrons is counted by a sum over the principal quantum number, which diverges due to the contribution from shallow bound (Rydberg) levels. A truncation of this sum is devised by application of the Planck–Larkin scheme to the Fermi distribution

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Guo, Li Shuai, Xing Rong Zheng, and Zhi Rong Wu. "The Chemistry Model of Ion-Ion Interaction Energy of Full Ionized Hydrogen Plasma." Advanced Materials Research 989-994 (July 2014): 779–82. http://dx.doi.org/10.4028/www.scientific.net/amr.989-994.779.

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The ion-ion interaction contribution to the Helmholtz free energy is one of thermodynamic properties which discribing full ionized hydrogen plasma. Based quantum statistical theory and its simulation results to construct the free energy model of statistical mechanics, it is great significant to understand the properties of full ionized hydrogen plasma under high temperatures and pressures. Using Fortran program, we calculated the isotherms with some sensitive parameters, making comparison between our results and the formers. We find that former formula proposed by Chabrier appears variation at ultra-high temperatures ( > Κ ), implying a prominent limit of low temperature, while we developed a more reasonable formula of the ion-ion interaction contribution to the Helmholtz free energy. Analyses on isotherm curves indicate that the thermodynamic properties of the ion-ion interaction contribution to the Helmholtz free energy described by our approximant is very stable at all temperatures and pressures without any unphysical effects at low temperatures.

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Yaseen, Salah, and G. Ali Mansoori. "Asphaltenes behavior during petroleum reservoirs acidizing (a molecular-scale onset study)." SOCAR Proceedings, no. 3 (September 30, 2020): 38–46. http://dx.doi.org/10.5510/ogp20200300443.

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In the present study, we report our findings on asphaltenic sludge formation onset during petroleum reservoir acidizing treatment. To achieve this goal, we perform a series of molecular dynamics (MD) simulations at high temperature and pressure (550 K, 200 bar) on asphaltenic-oil (containing different molecular structures of asphaltenes) /hydrochloric acid (HCl) systems. Our simulation results indicate formation of asphaltenic sludge onset due to reservoir acidizing. Accumulation of the ionized asphaltenes at the oil/aqueous interface is the cause of sludge formation onset. Presence of ionized asphaltenes at the oil/water interface is attributed to the strong ion-ion interaction between ionized asphaltenes and acid ions (H+ and Cl-). Sludge formation onset is further stabilized via hydrogen bonding forces between ionized asphaltenes and interfacial water.

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Rehak, N. N., S. A. Cecco, J. E. Niemela, E. N. Hristova, and R. J. Elin. "Linearity and stability of the AVL and Nova magnesium and calcium ion-selective electrodes." Clinical Chemistry 42, no. 6 (June 1, 1996): 880–87. http://dx.doi.org/10.1093/clinchem/42.6.880.

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Abstract We studied the stability and linearity of the AVL and Nova Mg and Ca ion-selective electrodes and the relation between the ionized Ca and ionized Mg results reported by each analyzer. The response of the electrodes to different concentrations of Mg and Ca was determined for saline solutions, aqueous solutions, and serum samples. The electrodes from both manufacturers demonstrated acceptable stability for the time of the study. The response of the electrodes was linear within the range specified by each manufacturer, but relative nonlinearity and the values for the linear limits differed between the AVL and Nova analyzers. The ionized Mg results varied with the concentration of Ca. The relation between ionized Ca and ionized Mg results was nonlinear and differed between the AVL and Nova electrodes. Intermethod comparison between the electrodes showed poor agreement for ionized Mg results, especially at low and high concentrations of total Ca and total Mg.

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8

Furkal, E., A. Smolyakov, and A. Hirose. "Nonlocal ion transport in a weakly ionized nonequilibrium plasma." IEEE Transactions on Plasma Science 26, no. 2 (April 1998): 198–207. http://dx.doi.org/10.1109/27.669628.

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9

Giardini-Guidoni, Anna, and Aldo Mele. "Production and Reactivity of Ionized Clusters in the Gas Phase." Laser Chemistry 11, no. 3-4 (January 1, 1991): 205–8. http://dx.doi.org/10.1155/lc.11.205.

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A brief review of the experimental methods to obtain gas phase cluster ions is reported. Supersonic expansion and ionization, high pressure ion production and clusterization, ablation from solids are techniques used to study cluster chemistry. Studies of cluster ion formation from metal, metal oxides and metal carbides are illustrated together with considerations on their structure and stability.

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10

Nakata, Yoshihiko, Satoshi Ninomiya, Chikage Imada, Masafumi Nagai, Takaaki Aoki, Jiro Matsuo, and Nobutsugu Imanishi. "Secondary neutral and ionized particle measurements under MeV-energy ion bombardment." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 230, no. 1-4 (April 2005): 489–94. http://dx.doi.org/10.1016/j.nimb.2004.12.089.

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11

CHANDEZON, F., C. GUET, B. A. HUBER, D. JALABERT, M. MAUREL, E. MONNAND, C. RISTORI, and J. C. ROCCO. "MULTIPLE IONIZATION OF SODIUM CLUSTERS BY ION IMPACT." Surface Review and Letters 03, no. 01 (February 1996): 529–33. http://dx.doi.org/10.1142/s0218625x96000966.

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The electronic excitation of alkali-metal clusters by low-energy ions is investigated experimentally for the first time. Multi-ionized clusters possibly undergoing Coulomb dissociation are formed and detected. Free sodium clusters of a few hundred atoms have been bombarded by different ion beams ( H +, O 5+, Ar 8+) of velocity ranging from 0.2 to 0.9v0. The mass/charge ratio of charged outgoing clusters is measured by a time-of-flight spectrometer of high resolution [Formula: see text]. Critical sizes for stability against charge excess have been deduced for cluster charges up to 6. Temperature effects on critical sizes are observed, and they reveal two distinct regimes: electron transfer in peripheral collisions with multicharged ions leading to “cold” highly ionized clusters and strong electronic excitation in central collisions subsequently followed by multielectron emission.

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12

Lettry, J., R. Catherall, U. Köster, U. Georg, O. Jonsson, S. Marzari, and V. Fedosseev. "Alkali suppression within laser ion-source cavities and time structure of the laser ionized ion-bunches." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 204 (May 2003): 363–67. http://dx.doi.org/10.1016/s0168-583x(02)01967-5.

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13

Aijaz, Asim, and Zaheer Uddin. "EFFECT OF ENERGETIC ION BOMBARDMENT DURING THE GROWTH OF HYDROGENATED AMORPHOUS CARBON THIN FILMS." JOURNAL OF ADVANCES IN PHYSICS 7, no. 2 (January 31, 2015): 1823–28. http://dx.doi.org/10.24297/jap.v7i2.1700.

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Hydrogenated amorphous carbon (a-C:H) thin film growth using plasma-assisted deposition is studied using Monte Carlo based simulation. The effect of energetic bombardment of the ionized depositing species as well as ionized buffer gas species on the film growth and the resulting film properties is investigated. The ion energies that assist the a-C:H film growth from low density structures to high density structures such as diamond-like carbon (DLC) are used and the effect of energy and composition of the depositing species on the C-C and C-H bonding and the film structure are analyzed. It is found that the ion bombardment favors the formation of a-C:H films with low H contents, high density and superior mechanical strength of the resulting thin films and is therefore an effective way to tailor-made a-C:H thin film growth for specific applications.

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14

Zheng, Xing Rong, Chun Ling Tian, Na Wu, Bo Wu, and Xiao Bing Wang. "Ion-Electron Interaction Contribution to the Helmholtz Free Energy for Fully Ionized Hydrogen Plasma." Applied Mechanics and Materials 229-231 (November 2012): 991–94. http://dx.doi.org/10.4028/www.scientific.net/amm.229-231.991.

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The Padé approximation is a very important description of thermodynamic properties of fully ionized hydrogen at high pressures and temperatures. By comparing of several reported Padé approximants via calculation of the ion-electron interaction contribution to the Helmholtz free energy of the fully ionized hydrogen plasma, we find that Padé approximant proposed by Stolzman gives an unphysical odd local minimal appears at low temperature( ), and gradually fade away with the increase of temperature, implying a prominent limit of low temperature. While Chabrier et al. developed a more reasonable Padé approximant for the contribution of ion-electron interaction on the Helmholtz free energy. Analyses on isotherm curves indicate that the thermodynamic properties of the ion-electron interaction contribution to the Helmholtz free energy described by the revised Padé approximant is very stable at all temperatures and pressures without any unphysical effects at low temperatures.

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15

Dietrich, K. G., K. Mahrt-Olt, J. Jacoby, E. Boggasch, M. Winkler, B. Heimrich, and D. H. H. Hoffmann. "Beam–plasma interaction experiments with heavy-ion beams." Laser and Particle Beams 8, no. 4 (December 1990): 583–93. http://dx.doi.org/10.1017/s0263034600009010.

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The progress of the experimental research program at GSI for studying beam-plasma interaction phenomena is reported. Heavy-ion beams from the new accelerator facility SIS/ESR at GSI-Darmstadt are now available for experiments, and will soon deliver ≥ 109 particles per pulse in 100 ns. Focused on a small sample of matter, the beams will be able to produce a high-density plasma and to permit investigation of interaction processes of heavy ions with hot ionized matter.For the intense beam from the new heavy-ion synchrotron (SIS), a fine-focus system has been designed to produce a high specific deposition power beam for target experiments with a beam-spot radius of 100 μm. We further discuss improvements of this lens system by nonconventional focusing devices such as plasma lenses.Intense-beam experiments at the RFQ Maxilac accelerator at GSI have already produced the first heavy-ion-induced plasma with a temperature of 0.75 eV. New diagnostic techniques for investigating ion-beam-induced plasmas are presented. The low-intensity beam from the GSI UNILAC has been used to measure energy deposition profiles of heavy ions in hot ionized matter. In this experiment an enhancement of the stopping power for heavy ions was observed. The current experimental research program tests basic plasma theory and addresses key issues of inertial confinement fusion driven by intense heavy-ion beams.

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16

Fell, Lorne M., Peter C. Burgers, Paul JA Ruttink, and Johan K. Terlouw. "The decarbonylation of ionized β-hydroxypyruvic acid: the hydrogen-bridged radical cation [CH2=O . . .H . . .==C-OH].+ studied by experiment and theory." Canadian Journal of Chemistry 76, no. 3 (March 1, 1998): 335–49. http://dx.doi.org/10.1139/v98-022.

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The intriguing gas-phase ion chemistry of β-hydroxypyruvic acid (HPA), HOCH2C(==O)COOH, has been investigated using tandem mass spectrometry (metastable ion (MI) and (multiple) collision-induced dissociation (CID) experiments, neutralization-reionization mass spectrometry (NRMS), 18O and D isotopic labelling on both the acid and its methyl ester) in conjunction with computational chemistry (ab initio MO and density functional theories). HPA does not enolize upon evaporation, but it retains its keto structure. When ionized, decarbonylation occurs and, depending on the internal-energy content, this dissociation reaction proceeds via two distinct routes. The source-generated, high-energy ions lose the keto C==O, not via a least-motion extrusion into ionized glycolic acid, HOCH2COOH.+ , but via a rearrangement that yields the title H-bridged radical cation CH2==O ... H ... O==C-OH.+ for which Δ Hf0 = 99 ± 3 kcal/mol. The long-lived low-energy ions enolize prior to decarbonylation and lose the carboxyl C==O. Again, this is not a least-motion extrusion (which would produce the most stable isomer, HOC(H)==C(OH)2.+ Δ Hf0 = 73 kcal/mol) but a rearrangement yielding the ion-dipole complex HOC(H)C==C==O.+/H2O. The methyl ester of HPA behaves analogously, yielding CH2==O... H ...O==C-OCH3.+ and HOC(H)C==C==O.+ / CH3OH upon decarbonylation of the high- and low-energy ions, respectively. Decarboxylation into the ylidion CH2OH2.+ characterizes the dissociation chemistry of both the title H-bridged ion and its glycolic acid isomer HOCH2COOH.+ . A computational analysis of this reaction (which satisfies the experimental observations) leads to the proposal that the decarboxylation of the acid occurs via CH2-O(H) ... H ... ==C==O.+ as the key intermediate, whereas the title H-bridged ion follows a higher energy route that involves ion-dipole rotations leading to the ionized carbene HO(H2)CO-C-OH.+ and the distonic ion H2O-C(H2)-O-C==O.+ as key intermediates.Key words: tandem mass spectrometry, hydrogen-bridged radical cation, hydroxypyruvic acid, ab initio calculations, keto-enol tautomerization, 18O labelling.

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Flammang, Robert, Julien De Winter, Pascal Gerbaux, Vinh Son Nguyen, and Minh Tho Nguyen. "Internal Energy Effects on the Ion/Molecule Reactions of Ionized Methyl Isocyanide." European Journal of Mass Spectrometry 14, no. 5 (April 1, 2008): 299–309. http://dx.doi.org/10.1255/ejms.936.

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Electron ionization of methyl isocyanide in various chemical ionization conditions is reported and, depending on the energy conditions used, different ion/molecule reactions are observed. It is proposed, on the basis of combined quantum chemical (DFT) calculations and tandem mass spectrometric experiments, that a common intermediate could be a cumulenic ionized dimer dissociating in the ion source following two energy depending competitive channels, a loss of a hydrogen atom and a loss of a methyl group. Proposed structures for new cumulenic ions are supported by collision experiments in the high (collisional activation) or/and low (collision-induced dissociations) translational energy regime.

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18

Yamada, I., and T. Takagi. "Current status of ionized-cluster beam technique: A low energy ion beam deposition." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 21, no. 1-4 (January 1987): 120–23. http://dx.doi.org/10.1016/0168-583x(87)90809-3.

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19

Markell, M. S., B. T. Altura, R. L. Barbour, and B. M. Altura. "Ionized and Total Magnesium Levels in Cyclosporin-Treated Renal Transplant Recipients: Relationship with Cholesterol and Cyclosporin Levels." Clinical Science 85, no. 3 (September 1, 1993): 315–18. http://dx.doi.org/10.1042/cs0850315.

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1. Ionized magnesium, measured using a newly developed ion-selective electrode, total magnesium, and ionized and total calcium were evaluated in 39 stable, long-term, cyclosporin-treated renal transplant recipients and compared with those of age-matched, non-transplanted control subjects. Total cholesterol, cyclosporin trough level, serum creatinine, time after-transplant and the ratio of ionized calcium to ionized magnesium were also measured in renal transplant recipients and the relationships between these variables and ionized and total magnesium were evaluated. 2. Renal transplant recipients exhibited marked deficits in ionized magnesium, with a mean value of 0.54 ±0.01 mmol/l as compared with 0.61 ± 0.006 mmol/l for normal control subjects (P ≦ 0.05), with a more moderate deficit in total magnesium. Values for ionized and total calcium did not differ. By stepwise linear multiple regression analysis, ionized magnesium was significantly related to cyclosporin trough level and total cholesterol but not to serum creatinine, time after transplant or the dose of cyclosporin. Ionized magnesium correlated inversely with cyclosporin trough level and directly with total cholesterol. The ratio of ionized calcium to ionized magnesium was elevated in renal transplant recipients when compared with control subjects and correlated positively with the cyclosporin trough level. 3. Deficits in ionized magnesium are common during the late post-transplant period in cyclosporin-treated renal transplant recipients. Ionized magnesium may be a more sensitive clinical parameter than total magnesium in this population, in whom total magnesium may be only mildly decreased in the setting of a severe deficit in ionized magnesium. 4. Ionized magnesium correlates with the cyclosporin level. Renal transplant recipients with high cyclosporin levels demonstrate the most severe deficits in ionized magnesium, and this finding could contribute to cyclosporin-induced hypertension and nephrotoxicity. The direct correlation between ionized magnesium and total cholesterol may result from a ‘masked magnesium deficiency’, as has been suggested in animal models, and requires further study. 5. Accelerated atherosclerosis observed after renal transplantation may relate to alterations in ionized magnesium and elevated ratios of ionized calcium to ionized magnesium, which are associated with atherogenesis in other models.

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Penent, Francis, Denis Cubaynes, Pascal Lablanquie, Jérôme Palaudoux, Ségolène Guilbaud, Olivier Moustier, Jérôme Guigand, and Jean-Marc Bizau. "Modification of a Cylindrical Mirror Analyzer for High Efficiency Photoelectron Spectroscopy on Ion Beams." Atoms 8, no. 4 (September 25, 2020): 63. http://dx.doi.org/10.3390/atoms8040063.

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An existing cylindrical mirror analyzer (CMA) that was initially equipped with eight channeltrons detectors has been modified to install large micro-channel plate detectors to perform parallel detection of electrons on an energy range corresponding to ~12% of the mean pass energy. This analyzer is dedicated to photoelectron spectroscopy of ions ionized by synchrotron radiation. The overall detection efficiency is increased by a factor of ~20 compared to the original analyzer. A proof of principle of the efficiency of the analyzer has been done for Xe5+ and Si+ ions and will allow photoelectron spectroscopy on many other ionic species.

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21

van Ingen, H. E., H. J. Huijgen, W. T. Kok, and G. T. Sanders. "Analytical evaluation of Kone Microlyte determination of ionized magnesium." Clinical Chemistry 40, no. 1 (January 1, 1994): 52–55. http://dx.doi.org/10.1093/clinchem/40.1.52.

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Abstract We performed an analytical evaluation of a commercially available instrument for determining ionized magnesium through use of a neutral carrier, liquid-membrane-based ion-selective electrode. Reproducibility (CV 2-4%), linearity (0.30-2.50 mmol/L), lower limit of detection (0.30 mmol/L), and absence of interference from Ca2+ indicate adequate performance for measuring ionized magnesium in plasma or serum samples in the normal to high-concentration range. Sodium in excess of 150 mmol/L caused a negative bias, which can be explained by ionic strength-induced changes in activity coefficients. The use of heparin as an anticoagulant must be restricted to concentrations < 15 units/mL because of the binding of magnesium to heparin. The mean +/- SD concentration of ionized magnesium and its fraction of total magnesium in 76 healthy volunteers were 0.56 +/- 0.05 mmol/L and 0.65 +/- 0.04, respectively.

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Baiysbayeva, Meruyet, Galiya Iskakova, Assel Izembayeva, Nurgul Batyrbayeva, Fatima Dikhanbayeva, and Gulnur Daribayeva. "Development of technology for macaroni products based on flour of grain crops and ion-zoned water." Eastern-European Journal of Enterprise Technologies 1, no. 11 (109) (February 27, 2021): 51–60. http://dx.doi.org/10.15587/1729-4061.2021.225001.

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The nutritional value of food is one of the most important factors that determine the health of the population. In the macaroni market, dietary and functional products, fortified macaroni products and products of high nutritional value occupy a small segment that does not exceed 1 %. In this regard, the development of an assortment of pasta with increased nutritional value, with a directionally changed chemical composition, is relevant. In the pasta industry, an increase in the nutritional and biological value of products is achieved through the introduction of non-traditional types of raw materials and special food additives into the recipe. To reduce the deteriorating effect of corn and amaranth flour on the pasta properties of flour from durum wheat, ionized water was used with a concentration of ions of 1,000, 2,000, 3,000, 4,000 units/cm3 and ozone of 2 mg/l. It was found that ionized water has a positive effect on the properties of gluten and the quality of pasta with the addition of corn and amaranth flour. It was determined that the best quality of pasta is achieved when using ionized water with an ion concentration of 3,000 units/cm3 and ozone 2 mg/l and at dosages of amaranth flour 17.5 %, corn flour – 20 % to pasta flour. Summing up the results of the experimental study, the amount of prescription components for the production of pasta with high nutritional and biological value was optimized

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Fearn, D. G. "Spacecraft ion propulsion development in the United Kingdom." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 211, no. 2 (February 1, 1997): 103–12. http://dx.doi.org/10.1243/0954410971532532.

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The on-board propulsion system dominates the design of many spacecraft, particularly as regards mass and volume. However, the mass of this system, sometimes 50 per cent or more of the total, can be reduced dramatically by using ion propulsion technology, rather than the more usual chemical thrusters. In an ion thruster, the propellant is ionized in an electrical discharge, then the positive ions are extracted from the resulting plasma and accelerated to a very high velocity by an electric field, forming an extremely energetic exhaust. This paper describes the development and status of the two UK ion propulsion systems, which have thrust levels in the 1-30 mN and 50-300 mN ranges.

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Li, Yun, Du, Guo, Zeng, Jiang, and Chen. "Design, Fabrication and Mass-spectrometric Studies of a Micro Ion Source for High-Field Asymmetric Waveform Ion Mobility Spectrometry." Micromachines 10, no. 5 (April 27, 2019): 286. http://dx.doi.org/10.3390/mi10050286.

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A needle-to-cylinder electrode, adopted as an ion source for high-field asymmetric ion mobility spectrometry (FAIMS), is designed and fabricated by lithographie, galvanoformung and abformung (LIGA) technology. The needle, with a tip diameter of 20 μm and thickness of 20 μm, and a cylinder, with a diameter of 400 μm, were connected to the negative high voltage and ground, respectively. A negative corona and glow discharge were realized. For acetone with a density of 99.7 ppm, ethanol with a density of 300 ppm, and acetic ether with a density of 99.3 ppm, the sample gas was ionized by the needle-to-cylinder chip and the ions were detected by an LTQ XL™ (Thermo Scientific Corp.) mass spectrometer. The mass spectra show that the ions are mainly the protonated monomer, the proton bound dimer, and an ion-H2O molecule cluster. In tandem with a FAIMS system, the FAIMS spectra show that the resolving power increases with an increase in the RF voltage. The obtained experimental results showed that the micro needle-to-cylinder chip may serve as a miniature, low cost and non-radioactive ion source for FAIMS.

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Poolcharuansin, Phitsanu, Artit Chingsungnoen, Nitisak Pasaja, and James Bradley. "An Inverted Magnetron Operating in HiPIMS Mode." Plasma 1, no. 2 (November 27, 2018): 277–84. http://dx.doi.org/10.3390/plasma1020024.

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An ionized physical vapor deposition technique for thin ferromagnetic films is proposed. The technique is based on high power impulse magnetron sputtering (HiPIMS) with positive discharge polarity. A gapped-target was employed as the cathode of the magnetron. By applying positive HiPIMS pulses to the anode, sputtered particles inside the magnetron source were ionized and extracted through the gap. Using a discharge current with a peak of about 13 A, an ion flux in the order of 1021 m−2s−1 was obtained at a distance of 45 mm from the magnetron. In addition, deposition rates of up to 1.1 Å/s for nickel films were achieved using a 30 Hz repetition rate and 300 µs pulse width.

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Huang, Shi Duo, Leonidas Kolaitis, and David M. Lubman. "Detection of Explosives Using Laser Desorption in Ion Mobility Spectrometry/Mass Spectrometry." Applied Spectroscopy 41, no. 8 (November 1987): 1371–76. http://dx.doi.org/10.1366/0003702874447365.

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Laser desorption is used to volatilize explosive materials for analysis by ion mobility/mass spectrometry measurements. The laser desorption is performed at relatively low power (< 107 W/cm2) so that mainly neutrals are produced, which are subsequently ionized by 63Ni-β-source induced ion-molecule reactions at atmospheric pressure. Atmospheric pressure ionization, together with the soft vaporization method, produces relatively simple spectra of the explosives investigated, yielding ions that are very characteristic of each molecule for identification. The technique has great potential for high sensitivity based upon the combination of complete laser vaporization of the sample and the API method, which is an extremely efficient form of ionization for these molecules with high electron affinities.

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Hewavitharana, Amitha K., Vasantha Mutucumarana, and Byron Kratochvil. "An ion exchange atomic absorption method for the determination of ionized calcium at millimolar levels." Canadian Journal of Chemistry 69, no. 12 (December 1, 1991): 1976–79. http://dx.doi.org/10.1139/v91-284.

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A quantitative ion exchange/atomic absorption method is described for measuring the fraction of free calcium in solution at millimolar levels. Sample solutions are equilibrated with a micro-column of strong-acid type cation-exchange resin under electrolyte concentrations (0.75 mol/L NaNO3) high enough to provide conditions where the calcium sorbed on the resin is proportional to the free calcium in solution. After a water wash, the sorbed calcium is eluted from the resin with nitric acid directly into an atomic absorption spectophotometer. Free calcium levels were estimated using calibration curves obtained over the range 0–5 mM calcium with a precision of ± 0.05 mM. The effect of magnesium, at concentrations twice that of calcium, on measured calcium levels is negligible. The method is pH insensitive over the range 5–7. Selectivity for free calcium in the presence of complexing ligands such as citrate and phosphate is high. The method shows promise for the determination of ionized calcium in biological systems. Key words: ion exchange, atomic absorption, free calcium determination, ion speciation.

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Xu, Min. "Calculation of Wavelengths, Transition Probabilities and Oscillator Strengths for E1 and M1 Transitions in Cu-Like Au Ion." Applied Mechanics and Materials 723 (January 2015): 799–803. http://dx.doi.org/10.4028/www.scientific.net/amm.723.799.

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Wavelengths, transition probabilities and oscillator strengths have been calculated for electric dipole (E1) transitions and magnetic dipole (M1) transitions in Cu-like Au ion. These values are obtained in the configuration interaction (CI) and using the fully relativistic multiconfiguration Dirac-Fock (MCDF) method including quantum electrodynamical (QED) effect and Breit correction. Obtained energy levels of some excited states in Cu-like Au ion from the method are generally in good agreement with valuable theoretical and experimental results. The calculation results indicate that for high-Z highly ionized atom, some forbidden transitions are very important.

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Veljković, M., O. Nešković, Tamara Ivetić, S. Veličković, and Tatjana Maksin. "Endohedral Encapsulation of Lithium in C₇₀." Materials Science Forum 480-481 (March 2005): 351–54. http://dx.doi.org/10.4028/www.scientific.net/msf.480-481.351.

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A new diatomic molecule-containing endohedral fullerenes were prepared by ion implantation technique (introducing negatively charged C70 into a low temperature lithium plasma column by a strong exial magnetic field).The species prepared were Li@C70 and Li2@C70 and ionized by surface ionization. Their existance was demonstrated through high sensitivity, magnetic mass spectrometer. The corresponding endohedral ions undergo the Rice shrinkwrap mechanism: a mass –analyzed ion spectrum demonstrates the loss of a C2 unit from the cage. The observed ionization energies of endohedral molecules were 5.1 " 0.1 eV and 5.3 " 0.1 eV, respectively.

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30

Brown, Ian G. "Vacuum Arc Plasma Guns and Ion Sources." Solid State Phenomena 107 (October 2005): 63–68. http://dx.doi.org/10.4028/www.scientific.net/ssp.107.63.

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Vacuum arc plasma can be formed using particularly uncomplicated hardware, providing a means for laboratory scale formation of dense and highly-ionized metal plasma. The simplicity and versatility of the approach has led to its widespread use in recent times for both fundamental and technological applications. When embodied in a plasma gun configuration, the source can provide a valuable tool for plasma deposition of metal and metal-containing thin films, including in plasma immersion configurations. When embodied in an ion source configuration, high current beams of metal ions can be formed, and such beams have found good use for ion implantation and particle accelerator injection. Here we briefly review vacuum arc plasma guns and ion sources, outlining some of the hardware embodiments that have been developed at Berkeley and used for various materials modification applications.

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31

Бабунц, Р. А., А. С. Гурин, И. В. Ильин, А. П. Бундакова, М. В. Музафарова, А. Г. Бадалян, Н. Г. Романов, and П. Г. Баранов. "Высокочастотная ЭПР-спектроскопия парамагнитных центров марганца в кристаллах GaAs : Mn." Физика твердого тела 63, no. 11 (2021): 1906. http://dx.doi.org/10.21883/ftt.2021.11.51596.146.

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High-frequency electron paramagnetic resonance (EPR) is used to study the unique properties of manganese centers in a GaAs:Mn crystal in strong magnetic fields at low temperatures. At frequencies of 94 and 130 GHz, EPR transitions were recorded in the MnGa2+ - SH complex, which is a manganese ion with spin S = 5/2, which replaces gallium (MnGa2+) and is an ionized acceptor (A–) associated via an isotropic antiferromagnetic exchange interaction with a shallow hole (SH) with angular momentum J = 3/2. A complex system of energy levels of this complex in a magnetic field and the possibility of accurately determining exchange interactions from EPR spectra are analyzed. Another complex was investigated, in which an ionized acceptor MnGa2+ interacts with a localized hole center in the form of a diamagnetic ion O2– replacing As. This complex, MnGa2+-OAs2-, is characterized by axial symmetry along the <111> axis of the cubic GaAs crystal and an anisotropic EPR spectrum. Due to the high Boltzmann factor, in our studies, the order of the fine structure spin levels of this complex was determined. The effect of the Boltzmann populations of the energy levels on the high-frequency EPR spectra was also demonstrated for the MnGa2+- SH complex.

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Miller, M. K., and J. A. Panitz. "Microscopy Milestones: Field Ion Microscopy, Atom Probe Field Ion Microscopy and Atom Probe Tomography." Microscopy and Microanalysis 6, S2 (August 2000): 1190–91. http://dx.doi.org/10.1017/s1431927600038447.

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Two of the most significant microscopy milestones that were achieved in the last century were the imaging of individual atoms and the identification of individual atoms. Both these remarkable achievements were due to Prof. E. W. Miiller and members of his group at Pennsylvania State University. Almost fifty years ago, Miiller introduced a new type of microscope in which a sharp needle-shaped specimen was pointed at a fluorescent screen, Fig. 1. By applying an appropriately high positive voltage to the specimen, image gas atoms near the apex of the specimen could be ionized and radially projected towards the screen where they produced highly magnified images of the specimen surface, Fig. 2. By cryogenically cooling the specimen and using helium as the image gas, the first images of individual atoms were obtained in a field ion microscope by Bahadur and Müller on October 11th, 1955.

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Hubička, Z., M. Čada, A. Kapran, J. Olejníček, P. Kšírová, M. Zanáška, P. Adámek, and M. Tichý. "Plasma Diagnostics in Reactive High-Power Impulse Magnetron Sputtering System Working in Ar + H2S Gas Mixture." Coatings 10, no. 3 (March 6, 2020): 246. http://dx.doi.org/10.3390/coatings10030246.

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A reactive high-power impulse magnetron sputtering system (HiPIMS) working in Ar + H2S gas mixture was investigated as a source for the deposition of iron sulfide thin films. As a sputtering material, a pure Fe target was used. Plasma parameters in this system were investigated by a time-resolved Langmuir probe, radio-frequency (RF) ion flux probe, quartz crystal monitor modified for measurement of the ionized fraction of depositing particles, and by optical emission spectroscopy. A wide range of mass flow rates of reactive gas H2S was used for the investigation of the deposition process. It was found that the deposition rate of iron sulfide thin films is not influenced by the flow rate of H2S reactive gas fed into the magnetron discharge although the target is covered by iron sulfide compound. The ionized fraction of depositing particles decreases from r ≈ 40% to r ≈ 20% as the flow rate of H2S, QH2S, changes from 0 to 19 sccm at the gas pressure around p ≈ 1 Pa in the reactor chamber. The electron concentration ne measured by the Langmuir probe at the position of the substrate decreases over this change of QH2S from 1018 down to 1017 m−3

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Wargelin, B., S. M. Kahn, W. Craig, and R. London. "Measurement of Carbon Ion Photoabsorption Cross Sections Using Laser Plasmas." International Astronomical Union Colloquium 115 (1990): 53–56. http://dx.doi.org/10.1017/s0252921100012124.

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AbstractLaser plasmas are well-suited to studies of ionic photoabsorption because they can provide highly ionized, low temperature plasmas of high column density, as well as bright, compact continuum X-ray sources which can illuminate the plasma under study. In our experiment, continuum X-rays from a gold laser plasma are partially absorbed as they traverse a carbon plasma and are then dispersed by a grazing incidence reflection grating. An X-ray imaging camera records both the absorbed and unabsorbed spectra simultaneously for later computer analysis to determine the photoabsorption cross sections for each carbon ion species.

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35

Graves, David B., and Richard A. Gottscho. "Computer Applications in Plasma Materials Processing." MRS Bulletin 16, no. 2 (February 1991): 16–22. http://dx.doi.org/10.1557/s0883769400057602.

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In manufacturing microelectronic and optoelectronic devices, thin solid films of various sorts are routinely deposited and etched using low pressure, weakly ionized plasmas. The term “plasma” in this context implies an ionized gas with nearly equal numbers of positive and negative charges. This definition is not very restrictive, so. there are an enormous number of phenomena that are termed plasmas. For example, very hot, magnetized, fully ionized plasmas exist in stellar environments and thermonuclear fusion experiments. High temperature electric arcs are a form of plasma as well. In contrast, the plasmas used in electronic materials processing are near room temperature and the gas is usually weakly ionized. Indeed, due to the sensitivity of electronic devices to high temperatures, their low operating temperature is one of the major advantages of plasma processes.Plasma processing is attractive because of two important physiochemical effects: energetic free electrons in the plasma (heated by applied electric fields) dissociate the neutral gas in the plasma to create chemically reactive species; and free positive ions are accelerated by the plasma electric fields to surfaces bounding the plasma. Reactive species created in the plasma diffuse to surfaces and adsorb; wafers to be processed are typically placed on one of these surfaces.The combination of neutral species adsorption and positive ion bombardment results in surface chemical reaction. If the products of the surface reaction are volatile, they leave the surface and etching results. If the products are involatile, a surface film grows.

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36

Petrie, Simon. "Rethinking the Mesosphere's Magnesium Ion Chemistry." Environmental Chemistry 2, no. 1 (2005): 25. http://dx.doi.org/10.1071/en04070.

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Environmental Context. Meteoric ablation profoundly influences the spectroscopic, chemical, and thermal properties of Earth’s upper atmosphere, yet much of the chemical processing of meteor-derived material remains a mystery. As the most abundant main-group metal in meteoric material, magnesium likely plays an important or dominant role but its mesospheric chemistry has received comparatively little study to date. Abstract. High-level quantum chemical calculations address the structural and thermochemical properties of several novel magnesium-containing molecular ions which, we argue, are relevant to the Mg+ chemistry initiated by meteoric ablation in the mesosphere. A model for Mg+ chemistry is evaluated, with results indicating that most ionized magnesium at altitudes of 90 km and below is rapidly hydrated due to the association reactions of the pivotal HOMg+ ion. The implications of this new mechanism, apparently leading towards noctilucent cloud nucleation by Mg+, are briefly explored.

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37

Brandl, Patricia G., and Jon W. Carnahan. "Examinations of Charge Transfer between Ionized He and P, S, and Cl in a Microwave-Induced Plasma." Applied Spectroscopy 49, no. 12 (December 1995): 1781–88. http://dx.doi.org/10.1366/0003702953965867.

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Charge transfer between monomer helium ions and nonmetals has been postulated to be the source of high nonmetal ion populations in high electron density (> 1014 e−/cm3) discharges. In this study, overpopulations of excited Cl, P, and S ion energy levels in a helium microwave-induced plasma are examined using ion and atom line emission intensity data and charge transfer theory. The resonance emission lines from phosphorous, sulfur, and chlorine were examined. To examine these highly energetic lines, wavelengths in the vacuum-ultraviolet and the ultraviolet-visible (UV-visible) spectral regions were monitored. Energy-level population calculations were performed on similar UV-visible emission data from the literature. Charge transfer ionization cross sections are calculated for these elements. To obtain an indication of the significance of charge transfer, these parameters are compared to the behavior that would be expected if the plasma were in local thermodynamic equilibrium, and kinetically dominant processes such as CT were not considered. These evaluations, with the aid of energy-level diagrams, help to explain the spectroscopic behavior of these nonmetals in the helium discharge.

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38

HOUDE, MARTIN, TALAYEH HEZAREH, HUA-BAI LI, and THOMAS G. PHILLIPS. "AMBIPOLAR DIFFUSION AND TURBULENT MAGNETIC FIELDS IN MOLECULAR CLOUDS." Modern Physics Letters A 26, no. 04 (February 10, 2011): 235–49. http://dx.doi.org/10.1142/s021773231103502x.

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We review the introduction and development of a novel method for the characterization of magnetic fields in star-forming regions. The technique is based on the comparison of spectral line profiles from coexistent neutral and ion molecular species commonly detected in molecular clouds, sites of star formation. Unlike other methods used to study magnetic fields in the cold interstellar medium, this ion/neutral technique is not based on spin interactions with the field. Instead, it relies on and takes advantage of the strong cyclotron coupling between the ions and magnetic fields, thus exposing what is probably the clearest observational manifestation of magnetic fields in the cold, weakly ionized gas that characterizes the interior of molecular clouds. We will show how recent development and modeling of the ensuing ion line narrowing effect leads to a determination of the ambipolar diffusion scale involving the turbulent component of magnetic fields in star-forming regions, as well as the strength of the ordered component of the magnetic field.

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39

Karl, T., A. Hansel, L. Cappellin, L. Kaser, I. Herdlinger, and W. Jud. "Selective measurements of isoprene and 2-methyl-3-buten-2-ol based on NO<sup>+</sup> ionization mass spectrometry." Atmospheric Chemistry and Physics Discussions 12, no. 8 (August 3, 2012): 19349–70. http://dx.doi.org/10.5194/acpd-12-19349-2012.

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Abstract. Biogenic VOC emissions are often dominated by 2-methyl-1,3-butadiene (isoprene) and 2-methyl-3-buten-2-ol (232 MBO). Here we explore the possibility for selectively distinguishing these species using NO+ as primary ion based on PTR-MS technology. High purity of NO+ (>90%) as a primary ion was achieved in laboratory and field experiments using a PTR-TOF-MS. Isoprene is ionized via charge transfer leading to the major product ion C5H8+ (>99%) (e.g. Spanel and Smith, 1998). 232 MBO undergoes a hydroxide ion transfer reaction resulting in the major product ion channel C5H9+ (>95%) (e.g. Amelynck et al., 2005). We show that both compounds are ionized with little fragmentation (<5%) under standard PTR-MS operating conditions. Typical sensitivities of 11.1±0.1 (isoprene) and 12.9±0.1 (232 MBO) ncps ppbv−1 were achieved, which correspond to limit of detections of 18 and 15 pptv, respectively for a 10 s integration time. Sensitivities decreased at higher collisional energies. Calibration experiments showed little humidity dependence. We tested the setup at a field site in Colorado dominated by ponderosa pine, a 232 MBO emitting plant species. Our measurements confirm 232 MBO as the dominant biogenic VOC at this site, exhibiting typical average daytime concentrations between 0.2–1.4 ppbv. The method is able to detect the presence of trace levels of isoprene (90–250 ppt) without any interference from 232 MBO, which would not be feasible using H3O+ ionization chemistry, and which currently also remains achallenge for other analytical techniques (e.g. gas chromatographic methods).

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40

Ibehej, Tomáš, Jakub Hromádka, and Rudolf Hrach. "Computer Simulation of Metal Ions Transport to Uneven Substrates during Ionized Plasma Vapour Deposition." Advances in Materials Science and Engineering 2017 (2017): 1–7. http://dx.doi.org/10.1155/2017/4283547.

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We present a computational study of processes taking place in a sheath region formed near a negatively biased uneven substrate during ionized plasma vapour deposition. The sputtered metal atoms are ionized on their way to substrate and they are accelerated in the sheath near the substrate. They are able to penetrate to high-aspect-ratio structures, for example, trenches, which can be, therefore, effectively coated. The main technique used was a two-dimensional particle simulation. The results of our model predict the energy and angular distributions of impinging ions in low-pressure conditions which are characteristic for this method and where typical continuous models fail due to unfulfilled assumptions. Input bulk plasma properties were computed by a “zero dimensional” global model which took into account more physical processes important on a scale of the whole magnetron chamber. Output parameters, such as electrostatic potential, energy of ions, and ion fluxes, were computed for wide range of conditions (electron density and substrate bias) to show the influence of these conditions on observed phenomena, penetration of sheath inside the trench, deceleration of argon and copper ions inside the trench, and local maxima of ion fluxes near the trench opening.

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41

MAEDA, K., Y. SASA, and M. UDA. "HIGH RESOLUTION SOFT X-RAY SPECTROMETER FOR CHEMICAL STATE ANALYSIS BY PIXE." International Journal of PIXE 02, no. 01 (January 1992): 19–32. http://dx.doi.org/10.1142/s0129083592000038.

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A soft X-ray crystal spectrometer designed for chemical state analysis by PIXE is described. A windowless, microchannel plate (MCP) electron multiplier combined with a photodiode array was used as a position-sensitive detector for X-rays diffracted by a plane crystal. The spectrometer was tested for Al Kα and Fe L X-ray spectra induced by 15 MeV N2+ ion impact. An energy resolution (FWHM) of 1.5 eV for the 1487 eV Al Kα1, 2 line was obtained for metallic Al, and satellite structures of Al Kα arising from multiply ionized states were well resolved. Fe L X-ray spectra were measured for Fe2O3 and metallic Fe. Chemical effects were clearly recognized in the Fe Lα/Lβ intensity ratio and in the intensity distributions of their multiple vacancy satellites.

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42

Bathgate, Stephen N., Marcela M. M. Bilek, Iver H. Cairns, and David R. McKenzie. "A thruster using magnetic reconnection to create a high-speed plasma jet." European Physical Journal Applied Physics 84, no. 2 (November 2018): 20801. http://dx.doi.org/10.1051/epjap/2018170421.

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Plasma thrusters propel spacecraft by the application of Lorentz forces to ionized propellants. Despite evidence that Lorentz forces resulting from magnetic reconnection in solar flares and Earth's magnetopause produce jets of energetic particles, magnetic reconnection has only recently been considered as a means of accelerating plasma in a thruster. Based on theoretical principles, a pulsed magnetic reconnection thruster consisting of two parallel-connected slit coaxial tubes was constructed. The thruster was operated in argon plasma produced by RF energy at 13.56 MHz. A 1.0 ms current pulse of up to 1500 A was applied to the tubes. Three results provide evidence for magnetic reconnection. (1) The production of high-energy electrons resembling the outflow that is observed in the reconnection of field lines in solar flares and in laboratory experiments. (2) The high-energy electron current coincided with the rise of the magnetic field in the thruster and was followed by a large ion current. (3) In accordance with known physics of magnetic reconnection, ion currents were found to increase as the plasma became less collisional. The Alfvén speed of the outflowing ions was calculated to be 8.48 × 103 m s−1 corresponding to an Isp of 860 s.

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43

Karl, T., A. Hansel, L. Cappellin, L. Kaser, I. Herdlinger-Blatt, and W. Jud. "Selective measurements of isoprene and 2-methyl-3-buten-2-ol based on NO<sup>+</sup> ionization mass spectrometry." Atmospheric Chemistry and Physics 12, no. 24 (December 17, 2012): 11877–84. http://dx.doi.org/10.5194/acp-12-11877-2012.

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Abstract. Biogenic VOC emissions are often dominated by 2-methyl-1,3-butadiene (isoprene) and 2-methyl-3-buten-2-ol (232 MBO). Here we explore the possibility to selectively distinguish these species using NO+ as a primary ion in a conventional PTR-MS equipped with an SRI unit. High purity of NO+ (>90%) as a primary ion was utilized in laboratory and field experiments using a conventional PTR-TOF-MS. Isoprene is ionized via charge transfer leading to the major product ion C5H8+ (>99%) (e.g. Spanel and Smith, 1998). 232 MBO undergoes a hydroxide ion transfer reaction resulting in the major product ion channel C5H9+ (>95%) (e.g. Amelynck et al., 2005). We show that both compounds are ionized with little fragmentation (>5%) under standard operating conditions. Typical sensitivities of 11.1 ± 0.1 (isoprene) and 12.9 ± 0.1 (232 MBO) ncps ppbv−1 were achieved, which correspond to limit of detections of 18 and 15 pptv respectively for a 10 s integration time. Sensitivities decreased at higher collisional energies. Calibration experiments showed little humidity dependence. We tested the setup at a field site in Colorado dominated by ponderosa pine, a 232 MBO emitting plant species. Our measurements confirm 232 MBO as the dominant biogenic VOC at this site, exhibiting typical average daytime concentrations between 0.2–1.4 ppbv. The method is able to detect the presence of trace levels of isoprene at this field site (90–250 ppt) without any interference from 232 MBO, which would not be feasible using H3O+ ionization chemistry, and which currently also remains a challenge for other analytical techniques (e.g. gas chromatographic methods).

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44

Wang, Xu, and Dong-Sheng Yang. "Bonding and structures of copper-aminopyridine complexes — High-resolution electron spectroscopy and ab initio calculations." Canadian Journal of Chemistry 87, no. 1 (January 1, 2009): 297–306. http://dx.doi.org/10.1139/v08-146.

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Copper complexes of x-aminopyridine (x = 2, 3, 4) were prepared in a laser vaporization supersonic molecular beam source and identified using laser photoionization time-of-flight mass spectrometry. These complexes were studied by pulsed-field ionization zero electron kinetic energy (ZEKE) spectroscopy and second-order Møller-Plesset perturbation theory. Three structures formed by Cu binding to the pyridine nitrogen (σα), the amino nitrogen (σβ), and the pyridine ring (π) were considered by the theoretical calculations, but only the σα structures with Cu binding to the pyridine nitrogen were confirmed by the spectroscopic measurements. Adiabatic ionization energies and metal-ligand and ligand-based vibrational frequencies of the σα complexes were measured from the ZEKE spectra, and the metal-ligand bond energies of the neutral and ionized complexes were predicted by the theory. The ionization energies of the Cu complexes are about 20 000 cm–1 lower than that of bare Cu atom. This ionization energy shift is the result of the stronger Cu+-ligand bonding because of the additional charge-dipole interaction in the ion. Although the three complexes are formed by Cu coordination to the pyridine nitrogen atom, the position of the amino group affects the metal-ligand bonding strengths in both neutral and ionized species. These effects include the structural resonance and hydrogen bonding in the neutral complexes and the electric dipole moment and bidentate bonding in the ions.Key words: photoelectron, PFI-ZEKE, ab initio, copper aminopyridine.

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45

Kidera, Masanori, Kazuya Takahashi, Shuichi Enomoto, Youhei Mitsubori, Akira Goto, and Yasushige Yano. "Development of a Novel Mass Spectrometer Equipped with an Electron Cyclotron Resonance Ion Source." European Journal of Mass Spectrometry 13, no. 4 (August 2007): 239–48. http://dx.doi.org/10.1255/ejms.883.

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The ionization efficiency of an electron cyclotron resonance ion source (ECRIS) is generally high and all elements can be fundamentally ionized by the high-temperature plasma. We focused our attention on the high potentiality of ECRIS as an ion source for mass spectrometers and attempted to customize a mass spectrometer equipped with an ECRIS. Precise measurements were performed by using an ECRIS that was specialized and customized for elemental analysis. By using the charge-state distribution and the isotope ratio, the problem of overlap, such as that observed in the spectra of isobars, could be solved without any significant improvement in the mass resolution. When the isotope anomaly (or serious mass discrimination effect) was not observed in ECR plasma, the system was found to be very effective for isotope analysis. In this paper, based on the spectrum (ion current as a function of an analyzing magnet current) results of low charged state distributions (2+, 3+, 4+, …) of noble gases, we discuss the feasibility of an elemental analysis system employing an ECRIS, particularly for isotopic analysis. The high-performance isotopic analysis obtained from an ECRIS mass spectrometer in this study suggests that it can be widely applied to several fields of scientific study that require elemental or isotopic analyses with high sensitivity.

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46

Yen, Hsi-Wei, Bo Zhao, Patrick M. Koch, Ruben Krasnopolsky, Zhi-Yun Li, Nagayoshi Ohashi, and Shigehisa Takakuwa. "Constraint on ion–neutral drift velocity in the Class 0 protostar B335 from ALMA observations." Astronomy & Astrophysics 615 (July 2018): A58. http://dx.doi.org/10.1051/0004-6361/201732195.

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Aims. Ambipolar diffusion can cause a velocity drift between ions and neutrals. This is one of the non-ideal magnetohydrodynamics (MHD) effects proposed to enable the formation of large-scale Keplerian disks with sizes of tens of au. To observationally study ambipolar diffusion in collapsing protostellar envelopes, we compare here gas kinematics traced by ionized and neutral molecular lines and discuss the implication on ambipolar diffusion. Methods. We analyzed the data of the H13CO+ (3–2) and C18O (2–1) emission in the Class 0 protostar B335 obtained with our ALMA observations. We constructed kinematical models to fit the velocity structures observed in the H13CO+ and C18O emission and to measure the infalling velocities of the ionized and neutral gas on a 100 au scale in B335. Results. A central compact (~1′′–2′′) component that is elongated perpendicular to the outflow direction and exhibits a clear velocity gradient along the outflow direction is observed in both lines and most likely traces the infalling flattened envelope. With our kinematical models, the infalling velocities in the H13CO+ and C18O emission are both measured to be 0.85 ± 0.2 km s−1 at a radius of 100 au, suggesting that the velocity drift between the ionized and neutral gas is at most 0.3 km s−1 at a radius of 100 au in B335. Conclusions. The Hall parameter for H13CO+ is estimated to be ≫1 on a 100 au scale in B335, so that H13CO+ is expected to be attached to the magnetic field. Our non-detection or upper limit of the velocity drift between the ionized and neutral gas could suggest that the magnetic field remains rather well coupled to the bulk neutral material on a 100 au scale in this source, and that any significant field-matter decoupling, if present, likely occurs only on a smaller scale, leading to an accumulation of magnetic flux and thus efficient magnetic braking in the inner envelope. This result is consistent with the expectation from the MHD simulations with a typical ambipolar diffusivity and those without ambipolar diffusion. On the other hand, the high ambipolar drift velocity of 0.5–1.0 km s−1 on a 100 au scale predicted in the MHD simulations with an enhanced ambipolar diffusivity by removing small dust grains, where the minimum grain size is 0.1 μm, is not detected in our observations. However, because of our limited angular resolution, we cannot rule out a significant ambipolar drift only in the midplane of the infalling envelope. Future observations with higher angular resolutions (~0. ′′1) are needed to examine this possibility and ambipolar diffusion on a smaller scale.

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47

Sion, Edward M., James Liebert, Gerard Vauclair, and Gary Wegner. "The Detection of Ionized Helium and Carbon in the Pulsating DB Degenerate GD358." International Astronomical Union Colloquium 114 (1989): 354–58. http://dx.doi.org/10.1017/s0252921100099863.

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Spectroscopic observations of hot white dwarfs utilizing the Explorer (IUE) high resolution spectrograph have led to the important discovery of ion absorption features (undetectable at low resolution) which have been ascribed to wind outflow in some cases (cf. Bruhweiler and Kondo 1983) and formation at the photosphere (cf. Sion and Guinan 1983; Bruhweiler and Kondo 1983; Dupree and Raymond 1982) in others. These line features, often weak and sharp, have presented a fundamental challenge to current understanding of the complex interplay of physical processes which control observed surface abundances in white dwarfs: gravitational/thermal diffusion, selective radiative support of ions, mass loss, convective dilution and mixing, and accretion (cf. the review by Vauclair, this volume and references therein).

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48

Mall, Urs. "Composition of the Solar Wind, Secondary Ion Generation and Pick-Up." Highlights of Astronomy 11, no. 2 (1998): 847–50. http://dx.doi.org/10.1017/s153929960001892x.

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The solar wind is an ionized gas which, as a consequence of a hot solar corona and a low fluid pressure in the interstellar space, continuously emanates from the Sun into space to define a region known as the heliosphere. Since the electrical conductivity of the solar wind is very high, diffusion of the magnetic field through the plasma is not taken into account. In this picture (the frozen-in approximation) one imagines that the solar magnetic field is dragged into the heliospheric space by the radially outflowing solar wind. The structure of the solar wind is therefore intimately related to the structure of the solar corona and the solar magnetic field. The solar wind plasma itself is composed of protons, electrons, alpha particles, and a minor fraction of heavy ions.

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Hoffmann, D. H. H., A. Blazevic, S. Korostiy, P. Ni, S. A. Pikuz, B. Rethfeld, O. Rosmej, et al. "Inertial fusion energy issues of intense heavy ion and laser beams interacting with ionized matter studied at GSI-Darmstadt." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 577, no. 1-2 (July 2007): 8–13. http://dx.doi.org/10.1016/j.nima.2007.02.005.

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50

Harfenist, EJ, MA Packham, RL Kinlough-Rathbone, M. Cattaneo, and JF Mustard. "Effect of calcium ion concentration on the ability of fibrinogen and von Willebrand factor to support the ADP-induced aggregation of human platelets." Blood 70, no. 3 (September 1, 1987): 827–31. http://dx.doi.org/10.1182/blood.v70.3.827.827.

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Abstract To investigate the suggestion that von Willebrand factor (vWf) can substitute for fibrinogen in supporting ADP-induced aggregation of human platelets, we studied platelet reactions in two media: (1) a high calcium medium, Tyrode-albumin solution containing calcium ions in the physiological range of 2 mmol/L, and (2) a low calcium medium, modified Tyrode-albumin solution from which calcium salt was omitted (calcium ion concentration approximately 20 mumol/L). In the high calcium medium vWf even at concentrations up to six times as high as physiological, showed little or no potentiation of ADP-induced platelet aggregation, whereas fibrinogen strongly potentiated reversible aggregation without thromboxane formation or release of granule contents. In the low calcium medium, either vWf or fibrinogen supported biphasic aggregation in response to ADP, with thromboxane formation and release of granule contents. Aspirin and the thromboxane receptor blocker BM 13.177 inhibited these secondary responses to von Willebrand factor, indicating that they require thromboxane A2 formation and feedback amplification by thromboxane A2. A monoclonal antibody, 10E5, to the platelet glycoprotein IIb/IIIa complex inhibited both primary and secondary aggregation. Although vWf supports ADP-induced aggregation when the concentration of ionized calcium is in the micromolar range, it does not support ADP-induced aggregation in the presence of a concentration of ionized calcium in the physiological range, indicating that vWf probably cannot substitute for fibrinogen in supporting ADP- induced aggregation in vivo.

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Journal articles on the topic 'High ionized ion'

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