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Mifsud DV, Herczku P, Rahul KK, Ramachandran R, Sundararajan P, Kovács STS, Sulik B, Juhász Z, Rácz R, Biri S, Kaňuchová Z, McCullough RW, Sivaraman B, Ioppolo S, Mason NJ. A systematic mid-infrared spectroscopic study of thermally processed SO 2 ices. Phys Chem Chem Phys 2023; 25:26278-26288. [PMID: 37747055 DOI: 10.1039/d3cp03196a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
The use of mid-infrared spectroscopy to characterise the chemistry of icy interstellar and Solar System environments will be exploited in the near future to better understand the chemical processes and molecular inventories in various astronomical environments. This is, in part, due to observational work made possible by the recently launched James Webb Space Telescope as well as forthcoming missions to the outer Solar System that will observe in the mid-infrared spectroscopic region (e.g., the Jupiter Icy Moons Explorer and the Europa Clipper missions). However, such spectroscopic characterisations are crucially reliant upon the generation of laboratory data for comparative purposes. In this paper, we present an extensive mid-infrared characterisation of SO2 ice condensed at several cryogenic temperatures between 20 and 100 K and thermally annealed to sublimation in an ultrahigh-vacuum system. Our results are anticipated to be useful in confirming the detection (and possibly thermal history) of SO2 on various Solar System bodies, such as Ceres and the icy Galilean moons of Jupiter, as well as in interstellar icy grain mantles.
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Affiliation(s)
- Duncan V Mifsud
- Centre for Astrophysics and Planetary Science, School of Physics and Astronomy, University of Kent, Canterbury, CT2 7NH, UK.
- Atomic and Molecular Physics Laboratory, Institute for Nuclear Research (Atomki), Debrecen H-4026, Hungary
| | - Péter Herczku
- Atomic and Molecular Physics Laboratory, Institute for Nuclear Research (Atomki), Debrecen H-4026, Hungary
| | - K K Rahul
- Atomic and Molecular Physics Laboratory, Institute for Nuclear Research (Atomki), Debrecen H-4026, Hungary
| | - Ragav Ramachandran
- Atomic, Molecular, and Optical Physics Division, Physical Research Laboratory, Ahmedabad 380009, India
| | - Pavithraa Sundararajan
- Atomic, Molecular, and Optical Physics Division, Physical Research Laboratory, Ahmedabad 380009, India
| | - Sándor T S Kovács
- Atomic and Molecular Physics Laboratory, Institute for Nuclear Research (Atomki), Debrecen H-4026, Hungary
| | - Béla Sulik
- Atomic and Molecular Physics Laboratory, Institute for Nuclear Research (Atomki), Debrecen H-4026, Hungary
| | - Zoltán Juhász
- Atomic and Molecular Physics Laboratory, Institute for Nuclear Research (Atomki), Debrecen H-4026, Hungary
| | - Richárd Rácz
- Atomic and Molecular Physics Laboratory, Institute for Nuclear Research (Atomki), Debrecen H-4026, Hungary
| | - Sándor Biri
- Atomic and Molecular Physics Laboratory, Institute for Nuclear Research (Atomki), Debrecen H-4026, Hungary
| | - Zuzana Kaňuchová
- Astronomical Institute, Slovak Academy of Sciences, Tatranská Lomnica, SK-059 60, Slovakia
| | - Robert W McCullough
- Department of Physics and Astronomy, School of Mathematics and Physics, Queen's University Belfast, Belfast, BT7 1NN, UK
| | - Bhalamurugan Sivaraman
- Atomic, Molecular, and Optical Physics Division, Physical Research Laboratory, Ahmedabad 380009, India
| | - Sergio Ioppolo
- Centre for Interstellar Catalysis (InterCat), Department of Physics and Astronomy, Aarhus University, Aarhus DK-8000, Denmark
- School of Electronic Engineering and Computer Science, Queen Mary University of London, London E1 4NS, UK
| | - Nigel J Mason
- Centre for Astrophysics and Planetary Science, School of Physics and Astronomy, University of Kent, Canterbury, CT2 7NH, UK.
- Atomic and Molecular Physics Laboratory, Institute for Nuclear Research (Atomki), Debrecen H-4026, Hungary
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Mifsud DV, Herczku P, Rácz R, Rahul KK, Kovács STS, Juhász Z, Sulik B, Biri S, McCullough RW, Kaňuchová Z, Ioppolo S, Hailey PA, Mason NJ. Energetic electron irradiations of amorphous and crystalline sulphur-bearing astrochemical ices. Front Chem 2022; 10:1003163. [PMID: 36226122 PMCID: PMC9549411 DOI: 10.3389/fchem.2022.1003163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 08/30/2022] [Indexed: 11/13/2022] Open
Abstract
Laboratory experiments have confirmed that the radiolytic decay rate of astrochemical ice analogues is dependent upon the solid phase of the target ice, with some crystalline molecular ices being more radio-resistant than their amorphous counterparts. The degree of radio-resistance exhibited by crystalline ice phases is dependent upon the nature, strength, and extent of the intermolecular interactions that characterise their solid structure. For example, it has been shown that crystalline CH3OH decays at a significantly slower rate when irradiated by 2 keV electrons at 20 K than does the amorphous phase due to the stabilising effect imparted by the presence of an extensive array of strong hydrogen bonds. These results have important consequences for the astrochemistry of interstellar ices and outer Solar System bodies, as they imply that the chemical products arising from the irradiation of amorphous ices (which may include prebiotic molecules relevant to biology) should be more abundant than those arising from similar irradiations of crystalline phases. In this present study, we have extended our work on this subject by performing comparative energetic electron irradiations of the amorphous and crystalline phases of the sulphur-bearing molecules H2S and SO2 at 20 K. We have found evidence for phase-dependent chemistry in both these species, with the radiation-induced exponential decay of amorphous H2S being more rapid than that of the crystalline phase, similar to the effect that has been previously observed for CH3OH. For SO2, two fluence regimes are apparent: a low-fluence regime in which the crystalline ice exhibits a rapid exponential decay while the amorphous ice possibly resists decay, and a high-fluence regime in which both phases undergo slow exponential-like decays. We have discussed our results in the contexts of interstellar and Solar System ice astrochemistry and the formation of sulphur allotropes and residues in these settings.
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Affiliation(s)
- Duncan V. Mifsud
- Centre for Astrophysics and Planetary Science, School of Physical Sciences, University of Kent, Canterbury, United Kingdom
- Institute for Nuclear Research (Atomki), Debrecen, Hungary
- *Correspondence: Duncan V. Mifsud, ; Péter Herczku, ; Nigel J. Mason,
| | - Péter Herczku
- Institute for Nuclear Research (Atomki), Debrecen, Hungary
- *Correspondence: Duncan V. Mifsud, ; Péter Herczku, ; Nigel J. Mason,
| | - Richárd Rácz
- Institute for Nuclear Research (Atomki), Debrecen, Hungary
| | - K. K. Rahul
- Institute for Nuclear Research (Atomki), Debrecen, Hungary
| | | | - Zoltán Juhász
- Institute for Nuclear Research (Atomki), Debrecen, Hungary
| | - Béla Sulik
- Institute for Nuclear Research (Atomki), Debrecen, Hungary
| | - Sándor Biri
- Institute for Nuclear Research (Atomki), Debrecen, Hungary
| | - Robert W. McCullough
- Department of Physics and Astronomy, School of Mathematics and Physics, Queen’s University Belfast, Belfast, United Kingdom
| | - Zuzana Kaňuchová
- Astronomical Institute, Slovak Academy of Sciences, Tatranská Lomnica, Slovakia
| | - Sergio Ioppolo
- School of Electronic Engineering and Computer Science, Queen Mary University of London, London, United Kingdom
| | - Perry A. Hailey
- Centre for Astrophysics and Planetary Science, School of Physical Sciences, University of Kent, Canterbury, United Kingdom
| | - Nigel J. Mason
- Centre for Astrophysics and Planetary Science, School of Physical Sciences, University of Kent, Canterbury, United Kingdom
- Institute for Nuclear Research (Atomki), Debrecen, Hungary
- *Correspondence: Duncan V. Mifsud, ; Péter Herczku, ; Nigel J. Mason,
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Thuillier T, Benitez J, Biri S, Rácz R. X-ray diagnostics of ECR ion sources-Techniques, results, and challenges. Rev Sci Instrum 2022; 93:021102. [PMID: 35232141 DOI: 10.1063/5.0076321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Accepted: 01/28/2022] [Indexed: 06/14/2023]
Abstract
The high magnetic confinement provided by the minimum-B structure of electron cyclotron resonance ion sources (ECRIS) hosts a non-equilibrium plasma, composed of cold multi-charged ions and hot electrons whose energy can expand up to ≈1 MeV. With a very limited accessibility, the ECR plasma is difficult to study. The x-ray photons generated by the interaction of the warm and hot electron populations within the plasma, as well as the photons generated by electrons lost to the chamber wall, are a signal of great interest as it gives an insight to the properties of the ECR plasma. After an introduction presenting the mechanism generating the x rays in ECRIS, this Review presents the methodology to measure x rays both for volumetric measurements and plasma imaging. The main insights of those measurements are presented. Prospects of x-ray measurements to better understand the plasma dynamics are finally highlighted.
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Affiliation(s)
- T Thuillier
- Univ. Grenoble Alpes, CNRS, Grenoble INP, LPSC-IN2P3, 38000 Grenoble, France
| | - J Benitez
- LBNL: One Cyclotron Road, Berkeley, California 94720, USA
| | - S Biri
- Institute for Nuclear Research (Atomki), Bem tér 18/c, 4026 Debrecen, Hungary
| | - R Rácz
- Institute for Nuclear Research (Atomki), Bem tér 18/c, 4026 Debrecen, Hungary
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Lampé I, Beke D, Biri S, Csarnovics I, Csik A, Dombrádi Z, Hajdu P, Hegedűs V, Rácz R, Varga I, Hegedűs C. Investigation of silver nanoparticles on titanium surface created by ion implantation technology. Int J Nanomedicine 2019; 14:4709-4721. [PMID: 31308654 PMCID: PMC6616303 DOI: 10.2147/ijn.s197782] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Accepted: 04/16/2019] [Indexed: 01/15/2023] Open
Abstract
Objectives: Using dental Ti implants has become a well-accepted and used method for replacing missing dentition. It has become evident that in many cases peri-implant inflammation develops. The objective was to create and evaluate the antibacterial effect of silver nanoparticle (Ag-NP) coated Ti surfaces that can help to prevent such processes if applied on the surface of dental implants. Methods: Annealing I, Ag ion implantation by the beam of an Electron Cyclotron Resonance Ion Source (ECRIS), Ag Physical Vapor Deposition (PVD), Annealing II procedures were used, respectively, to create a safely anchored Ag-NP layer on 1x1 cm2 Grade 2 titanium samples. The antibacterial effect was evaluated by culturing Staphylococcus aureus (ATCC 29213) on the surfaces of the samples for 8 hours, and comparing the results to that of glass as control and of pure titanium samples. Alamar Blue assay was carried out to check cytotoxicity. Results: It was proved that silver nanoparticles were present on the treated surfaces. The average diameter of the particles was 58 nm, with a 25 nm deviation and Gaussian distribution, the the filling factor was 25%. Antibacterial evaluation revealed that the nanoparticle covered samples had an antibacterial effect of 64.6% that was statistically significant. Tests also proved that the nanoparticles are safely anchored to the titanium surface and are not cytotoxic. Conclusion: Creating a silver nanoparticle layer can be an option to add antibacterial features to the implant surface and to help in the prevention of peri-implant inflammatory processes. Recent studies demonstrated that silver nanoparticles can induce pathology in mammal cells, thus safe fixation of the particles is essential to prevent them from getting into the circulation.
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Affiliation(s)
- István Lampé
- Department of Biomaterials and Prosthetic Dentistry, Faculty of Dentistry, University of Debrecen, Debrecen, Hungary
| | - Dezső Beke
- Department of Solid State Physics, University of Debrecen, Debrecen, Hungary
| | - Sándor Biri
- Hungarian Academy of Sciences, Institute for Nuclear Research, Debrecen, Hungary
| | - István Csarnovics
- Department of Experimental Physics, Faculty of Science and Technology, University of Debrecen, Debrecen, Hungary
| | - Attila Csik
- Hungarian Academy of Sciences, Institute for Nuclear Research, Debrecen, Hungary
| | - Zsuzsanna Dombrádi
- Department of Medical Microbiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Péter Hajdu
- Hungarian Academy of Sciences, Institute for Nuclear Research, Debrecen, Hungary
| | - Viktória Hegedűs
- Department of Orthodontics, Faculty of Dentistry, University of Debrecen, Debrecen, Hungary
| | - Richárd Rácz
- Hungarian Academy of Sciences, Institute for Nuclear Research, Debrecen, Hungary
| | - István Varga
- Department of Periodontology, Faculty of Dentistry, University of Debrecen, Debrecen, Hungary
| | - Csaba Hegedűs
- Department of Biomaterials and Prosthetic Dentistry, Faculty of Dentistry, University of Debrecen, Debrecen, Hungary
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Varga G, DenBesten P, Rácz R, Zsembery Á. Importance of bicarbonate transport in pH control during amelogenesis - need for functional studies. Oral Dis 2017; 24:879-890. [PMID: 28834043 DOI: 10.1111/odi.12738] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 08/13/2017] [Indexed: 12/27/2022]
Abstract
Dental enamel, the hardest mammalian tissue, is produced by ameloblasts. Ameloblasts show many similarities to other transporting epithelia although their secretory product, the enamel matrix, is quite different. Ameloblasts direct the formation of hydroxyapatite crystals, which liberate large quantities of protons that then need to be buffered to allow mineralization to proceed. Buffering requires a tight pH regulation and secretion of bicarbonate by ameloblasts. Many investigations have used immunohistochemical and knockout studies to determine the effects of these genes on enamel formation, but up till recently very little functional data were available for mineral ion transport. To address this, we developed a novel 2D in vitro model using HAT-7 ameloblast cells. HAT-7 cells can be polarized and develop functional tight junctions. Furthermore, they are able to accumulate bicarbonate ions from the basolateral to the apical fluid spaces. We propose that in the future, the HAT-7 2D system along with similar cellular models will be useful to functionally model ion transport processes during amelogenesis. Additionally, we also suggest that similar approaches will allow a better understanding of the regulation of the cycling process in maturation-stage ameloblasts, and the pH sensory mechanisms, which are required to develop sound, healthy enamel.
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Affiliation(s)
- G Varga
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - P DenBesten
- Department of Orofacial Sciences, University of California, San Francisco, CA, USA
| | - R Rácz
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - Á Zsembery
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
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Rácz R, Biri S, Pálinkás J, Mascali D, Castro G, Caliri C, Romano FP, Gammino S. X-ray pinhole camera setups used in the Atomki ECR Laboratory for plasma diagnostics. Rev Sci Instrum 2016; 87:02A741. [PMID: 26931959 DOI: 10.1063/1.4933085] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Imaging of the electron cyclotron resonance (ECR) plasmas by using CCD camera in combination with a pinhole is a non-destructive diagnostics method to record the strongly inhomogeneous spatial density distribution of the X-ray emitted by the plasma and by the chamber walls. This method can provide information on the location of the collisions between warm electrons and multiple charged ions/atoms, opening the possibility to investigate the direct effect of the ion source tuning parameters to the plasma structure. The first successful experiment with a pinhole X-ray camera was carried out in the Atomki ECR Laboratory more than 10 years ago. The goal of that experiment was to make the first ECR X-ray photos and to carry out simple studies on the effect of some setting parameters (magnetic field, extraction, disc voltage, gas mixing, etc.). Recently, intensive efforts were taken to investigate now the effect of different RF resonant modes to the plasma structure. Comparing to the 2002 experiment, this campaign used wider instrumental stock: CCD camera with a lead pinhole was placed at the injection side allowing X-ray imaging and beam extraction simultaneously. Additionally, Silicon Drift Detector (SDD) and High Purity Germanium (HPGe) detectors were installed to characterize the volumetric X-ray emission rate caused by the warm and hot electron domains. In this paper, detailed comparison study on the two X-ray camera and detector setups and also on the technical and scientific goals of the experiments is presented.
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Affiliation(s)
- R Rácz
- Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/C, H-4026 Debrecen, Hungary
| | - S Biri
- Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/C, H-4026 Debrecen, Hungary
| | - J Pálinkás
- Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/C, H-4026 Debrecen, Hungary
| | - D Mascali
- Instituto Nazionale di Fisica Nucleare-Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania, Italy
| | - G Castro
- Instituto Nazionale di Fisica Nucleare-Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania, Italy
| | - C Caliri
- Instituto Nazionale di Fisica Nucleare-Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania, Italy
| | - F P Romano
- Instituto Nazionale di Fisica Nucleare-Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania, Italy
| | - S Gammino
- Instituto Nazionale di Fisica Nucleare-Laboratori Nazionali del Sud, via S. Sofia 62, 95123 Catania, Italy
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Kitagawa A, Drentje AG, Fujita T, Muramatsu M, Fukushima K, Shiraishi N, Suzuki T, Takahashi K, Takasugi W, Biri S, Rácz R, Kato Y, Uchida T, Yoshida Y. Recent developments of ion sources for life-science studies at the Heavy Ion Medical Accelerator in Chiba (invited). Rev Sci Instrum 2016; 87:02C107. [PMID: 26932117 DOI: 10.1063/1.4934843] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
With about 1000-h of relativistic high-energy ion beams provided by Heavy Ion Medical Accelerator in Chiba, about 70 users are performing various biology experiments every year. A rich variety of ion species from hydrogen to xenon ions with a dose rate of several Gy/min is available. Carbon, iron, silicon, helium, neon, argon, hydrogen, and oxygen ions were utilized between 2012 and 2014. Presently, three electron cyclotron resonance ion sources (ECRISs) and one Penning ion source are available. Especially, the two frequency heating techniques have improved the performance of an 18 GHz ECRIS. The results have satisfied most requirements for life-science studies. In addition, this improved performance has realized a feasible solution for similar biology experiments with a hospital-specified accelerator complex.
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Affiliation(s)
- A Kitagawa
- National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan
| | - A G Drentje
- National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan
| | - T Fujita
- National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan
| | - M Muramatsu
- National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan
| | - K Fukushima
- Accelerator Engineering Corporation, Chiba, Japan
| | - N Shiraishi
- Accelerator Engineering Corporation, Chiba, Japan
| | - T Suzuki
- Accelerator Engineering Corporation, Chiba, Japan
| | - K Takahashi
- Accelerator Engineering Corporation, Chiba, Japan
| | - W Takasugi
- Accelerator Engineering Corporation, Chiba, Japan
| | - S Biri
- Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/C, H-4026 Debrecen, Hungary
| | - R Rácz
- Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/C, H-4026 Debrecen, Hungary
| | - Y Kato
- Graduate School of Engineering, Osaka University, Osaka, Japan
| | - T Uchida
- Bio-Nano Electronics Research Centre, Toyo University, Kawagoe, Japan
| | - Y Yoshida
- Bio-Nano Electronics Research Centre, Toyo University, Kawagoe, Japan
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Mascali D, Castro G, Biri S, Rácz R, Pálinkás J, Caliri C, Celona L, Neri L, Romano FP, Torrisi G, Gammino S. Electron cyclotron resonance ion source plasma characterization by X-ray spectroscopy and X-ray imaging. Rev Sci Instrum 2016; 87:02A510. [PMID: 26931918 DOI: 10.1063/1.4939201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
An experimental campaign aiming to investigate electron cyclotron resonance (ECR) plasma X-ray emission has been recently carried out at the ECRISs-Electron Cyclotron Resonance Ion Sources laboratory of Atomki based on a collaboration between the Debrecen and Catania ECR teams. In a first series, the X-ray spectroscopy was performed through silicon drift detectors and high purity germanium detectors, characterizing the volumetric plasma emission. The on-purpose developed collimation system was suitable for direct plasma density evaluation, performed "on-line" during beam extraction and charge state distribution characterization. A campaign for correlating the plasma density and temperature with the output charge states and the beam intensity for different pumping wave frequencies, different magnetic field profiles, and single-gas/gas-mixing configurations was carried out. The results reveal a surprisingly very good agreement between warm-electron density fluctuations, output beam currents, and the calculated electromagnetic modal density of the plasma chamber. A charge-coupled device camera coupled to a small pin-hole allowing X-ray imaging was installed and numerous X-ray photos were taken in order to study the peculiarities of the ECRIS plasma structure.
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Affiliation(s)
- David Mascali
- INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania, Italy
| | - Giuseppe Castro
- INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania, Italy
| | - Sándor Biri
- Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/c, H-4026 Debrecen, Hungary
| | - Richárd Rácz
- Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/c, H-4026 Debrecen, Hungary
| | - József Pálinkás
- Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/c, H-4026 Debrecen, Hungary
| | - Claudia Caliri
- INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania, Italy
| | - Luigi Celona
- INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania, Italy
| | - Lorenzo Neri
- INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania, Italy
| | | | - Giuseppe Torrisi
- INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania, Italy
| | - Santo Gammino
- INFN-Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania, Italy
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Uchida T, Rácz R, Muramatsu M, Kato Y, Kitagawa A, Biri S, Yoshida Y. Two-chamber configuration of Bio-Nano electron cyclotron resonance ion source for fullerene modification. Rev Sci Instrum 2016; 87:02A720. [PMID: 26931938 DOI: 10.1063/1.4934649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report on the modification of fullerenes with iron and chlorine using two individually controllable plasmas in the Bio-Nano electron cyclotron resonance ion source (ECRIS). One of the plasmas is composed of fullerene and the other one is composed of iron and chlorine. The online ion beam analysis allows one to investigate the rate of the vapor-phase collisional modification process in the ECRIS, while the offline analyses (e.g., liquid chromatography-mass spectrometry) of the materials deposited on the plasma chamber can give information on the surface-type process. Both analytical methods show the presence of modified fullerenes such as fullerene-chlorine, fullerene-iron, and fullerene-chlorine-iron.
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Affiliation(s)
- T Uchida
- Bio-Nano Electronics Research Centre, Toyo University, Kawagoe 350-8585, Japan
| | - R Rácz
- Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/C, H-4026 Debrecen, Hungary
| | - M Muramatsu
- National Institute of Radiological Sciences (NIRS), Chiba 263-8555, Japan
| | - Y Kato
- Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
| | - A Kitagawa
- National Institute of Radiological Sciences (NIRS), Chiba 263-8555, Japan
| | - S Biri
- Institute for Nuclear Research (Atomki), Hungarian Academy of Sciences, Bem tér 18/C, H-4026 Debrecen, Hungary
| | - Y Yoshida
- Bio-Nano Electronics Research Centre, Toyo University, Kawagoe 350-8585, Japan
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Spädtke P, Lang R, Mäder J, Maimone F, Schlei BR, Tinschert K, Biri S, Rácz R. Ion beam emittance from an ECRIS. Rev Sci Instrum 2016; 87:02A724. [PMID: 26931942 PMCID: PMC4636505 DOI: 10.1063/1.4934210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 10/08/2015] [Indexed: 06/05/2023]
Abstract
Simulation of ion beam extraction from an Electron Cyclotron Resonance Ion Source (ECRIS) is a fully 3 dimensional problem, even if the extraction geometry has cylindrical symmetry. Because of the strong magnetic flux density, not only the electrons are magnetized but also the Larmor radius of ions is much smaller than the geometrical dimension of the plasma chamber (Ø 64 × 179 mm). If we assume that the influence of collisions is small on the path of particles, we can do particle tracking through the plasma if the initial coordinates of particles are known. We generated starting coordinates of plasma ions by simulation of the plasma electrons, accelerated stochastically by the 14.5 GHz radio frequency power fed to the plasma. With that we were able to investigate the influence of different electron energies on the extracted beam. Using these assumptions, we can reproduce the experimental results obtained 10 years ago, where we monitored the beam profile with the help of viewing targets. Additionally, methods have been developed to investigate arbitrary 2D cuts of the 6D phase space. To this date, we are able to discuss full 4D information. Currently, we extend our analysis tool towards 5D and 6D, respectively.
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Affiliation(s)
- P Spädtke
- Gesellschaft für Schwerionenforschung (GSI), Darmstadt, Germany
| | - R Lang
- Gesellschaft für Schwerionenforschung (GSI), Darmstadt, Germany
| | - J Mäder
- Gesellschaft für Schwerionenforschung (GSI), Darmstadt, Germany
| | - F Maimone
- Gesellschaft für Schwerionenforschung (GSI), Darmstadt, Germany
| | - B R Schlei
- Gesellschaft für Schwerionenforschung (GSI), Darmstadt, Germany
| | - K Tinschert
- Gesellschaft für Schwerionenforschung (GSI), Darmstadt, Germany
| | - S Biri
- MTA Atomki, Debrecen, Hungary
| | - R Rácz
- MTA Atomki, Debrecen, Hungary
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Bori E, Guo J, Rácz R, Burghardt B, Földes A, Kerémi B, Harada H, Steward MC, Den Besten P, Bronckers ALJJ, Varga G. Evidence for Bicarbonate Secretion by Ameloblasts in a Novel Cellular Model. J Dent Res 2016; 95:588-96. [PMID: 26792171 DOI: 10.1177/0022034515625939] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Formation and growth of hydroxyapatite crystals during amelogenesis generate a large number of protons that must be neutralized, presumably by HCO3 (-)ions transported from ameloblasts into the developing enamel matrix. Ameloblasts express a number of transporters and channels known to be involved in HCO3 (-)transport in other epithelia. However, to date, there is no functional evidence for HCO3 (-)transport in these cells. To address questions related to HCO3 (-)export from ameloblasts, we have developed a polarized 2-dimensional culture system for HAT-7 cells, a rat cell line of ameloblast origin. HAT-7 cells were seeded onto Transwell permeable filters. Transepithelial resistance was measured as a function of time, and the expression of transporters and tight junction proteins was investigated by conventional and quantitative reverse transcription polymerase chain reaction. Intracellular pH regulation and HCO3 (-)transport were assessed by microfluorometry. HAT-7 cells formed epithelial layers with measureable transepithelial resistance on Transwell permeable supports and expressed claudin-1, claudin-4, and claudin-8-key proteins for tight junction formation. Transport proteins previously described in maturation ameloblasts were also present in HAT-7 cells. Microfluorometry showed that the HAT-7 cells were polarized with a high apical membrane CO2 permeability and vigorous basolateral HCO3 (-)uptake, which was sensitive to Na(+)withdrawal, to the carbonic anhydrase inhibitor acetazolamide and to H2DIDS inhibition. Measurements of transepithelial HCO3 (-)transport showed a marked increase in response to Ca(2+)- and cAMP-mobilizing stimuli. Collectively, 2-dimensional HAT-7 cell cultures on permeable supports 1) form tight junctions, 2) express typical tight junction proteins and electrolyte transporters, 3) are functionally polarized, and 4) can accumulate HCO3 (-)ions from the basolateral side and secrete them at the apical membrane. These studies provide evidence for a regulated, vectorial, basolateral-to-apical bicarbonate transport in polarized HAT-7 cells. We therefore propose that the HAT-7 cell line is a useful functional model for studying electrolyte transport by ameloblasts.
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Affiliation(s)
- E Bori
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - J Guo
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam, MOVE Research Institute, Amsterdam, Netherlands
| | - R Rácz
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - B Burghardt
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - A Földes
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - B Kerémi
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - H Harada
- Department of Anatomy, Division of Developmental Biology and Regenerative Medicine, Iwate Medical University, Iwate, Japan
| | - M C Steward
- Faculty of Life Sciences, The University of Manchester, Manchester, UK
| | - P Den Besten
- Department of Orofacial Sciences, University of California, San Francisco, CA, USA
| | - A L J J Bronckers
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam, University of Amsterdam and VU University Amsterdam, MOVE Research Institute, Amsterdam, Netherlands
| | - G Varga
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
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12
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Drentje AG, Kitagawa A, Uchida T, Rácz R, Biri S. Experiments with biased side electrodes in electron cyclotron resonance ion sources. Rev Sci Instrum 2014; 85:02A921. [PMID: 24593500 DOI: 10.1063/1.4827309] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The output of highly charged ions from an electron cyclotron resonance ion source (ECRIS) consists of ionic losses from a highly confined plasma. Therefore, an increase of the output of the ions of interest always is a compromise between an increase in the confinement and an increase of the losses. One route towards a solution consists of attacking the losses in directions - i.e., radial directions - that do not contribute to the required output. This was demonstrated in an experiment (using the Kei ECRIS at NIRS, Japan) where radial losses were electrostatically reduced by positively biasing one set of six "side" electrodes surrounding the plasma in side-ward directions attached (insulated) to the cylindrical wall of the plasma chamber. Recently new studies were performed in two laboratories using two essentially different ion sources. At the BioNano ECRIS (Toyo University, Japan) various sets of electrodes were used; each of the electrodes could be biased individually. At the Atomki ECRIS (Hungary), one movable, off-axis side electrode was applied in technically two versions. The measurements show indeed a decrease of ionic losses but different effectivities as compared to the biased disk.
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Affiliation(s)
- A G Drentje
- National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi 263-8555, Japan
| | - A Kitagawa
- National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi 263-8555, Japan
| | - T Uchida
- Bio-Nano Electronics Research Centre, Toyo University, 2100 Kujirai, Kawagoe-shi 350-8585, Japan
| | - R Rácz
- Institute for Nuclear Research (Atomki), H-2026 Debrecen, Bem ter 18/c, Hungary
| | - S Biri
- Institute for Nuclear Research (Atomki), H-2026 Debrecen, Bem ter 18/c, Hungary
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13
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Minezaki H, Ishihara S, Uchida T, Muramatsu M, Rácz R, Asaji T, Kitagawa A, Kato Y, Biri S, Yoshida Y. Synthesis of endohedral iron-fullerenes by ion implantation. Rev Sci Instrum 2014; 85:02A945. [PMID: 24593524 DOI: 10.1063/1.4850756] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In this paper, we discuss the results of our study of the synthesis of endohedral iron-fullerenes. A low energy Fe(+) ion beam was irradiated to C60 thin film by using a deceleration system. Fe(+)-irradiated C60 thin film was analyzed by high performance liquid chromatography and laser desorption/ ionization time-of-flight mass spectrometry. We investigated the performance of the deceleration system for using a Fe(+) beam with low energy. In addition, we attempted to isolate the synthesized material from a Fe(+)-irradiated C60 thin film by high performance liquid chromatography.
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Affiliation(s)
- H Minezaki
- Graduate School of Engineering, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585, Japan
| | - S Ishihara
- Graduate School of Engineering, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585, Japan
| | - T Uchida
- Bio-Nano Electronics Research Centre, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585, Japan
| | - M Muramatsu
- National Institute of Radiological Sciences (NIRS), 4-9-1, Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - R Rácz
- Institute of Nuclear Research (ATOMKI), Bem tér 18/C, H-4026 Debrecen, Hungary
| | - T Asaji
- Oshima National College of Maritime Technology, 1091-1, Komatsu Suou Oshima-city Oshima, Yamaguchi 742-2193, Japan
| | - A Kitagawa
- National Institute of Radiological Sciences (NIRS), 4-9-1, Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Y Kato
- Graduate School of Engineering, Osaka University, 2-1, Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - S Biri
- Institute of Nuclear Research (ATOMKI), Bem tér 18/C, H-4026 Debrecen, Hungary
| | - Y Yoshida
- Graduate School of Engineering, Toyo University, 2100, Kujirai, Kawagoe, Saitama 350-8585, Japan
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Rácz R, Biri S, Hajdu P, Pálinkás J. Fast camera studies at an electron cyclotron resonance table plasma generator. Rev Sci Instrum 2014; 85:02A507. [PMID: 24593430 DOI: 10.1063/1.4847215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A simple table-size ECR plasma generator operates in the ATOMKI without axial magnetic trap and without any particle extraction tool. Radial plasma confinement is ensured by a NdFeB hexapole. The table-top ECR is a simplified version of the 14 GHz ATOMKI-ECRIS. Plasma diagnostics experiments are planned to be performed at this device before installing the measurement setting at the "big" ECRIS. Recently, the plasma generator has been operated in pulsed RF mode in order to investigate the time evolution of the ECR plasma in two different ways. (1) The visible light radiation emitted by the plasma was investigated by the frames of a fast camera images with 1 ms temporal resolution. Since the visible light photographs are in strong correlation with the two-dimensional spatial distribution of the cold electron components of the plasma it can be important to understand better the transient processes just after the breakdown and just after the glow. (2) The time-resolved ion current on a specially shaped electrode was measured simultaneously in order to compare it with the visible light photographs. The response of the plasma was detected by changing some external setting parameters (gas pressure and microwave power) and was described in this paper.
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Affiliation(s)
- R Rácz
- Institute for Nuclear Research (ATOMKI), H-4026 Debrecen, Bem tér 18/c, Hungary
| | - S Biri
- Institute for Nuclear Research (ATOMKI), H-4026 Debrecen, Bem tér 18/c, Hungary
| | - P Hajdu
- Department of Experimental Physics, University of Debrecen, H-4032 Debrecen, Egyetem tér 1, Hungary
| | - J Pálinkás
- Department of Experimental Physics, University of Debrecen, H-4032 Debrecen, Egyetem tér 1, Hungary
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Biri S, Kitagawa A, Muramatsu M, Drentje AG, Rácz R, Yano K, Kato Y, Sasaki N, Takasugi W. Two-frequency heating technique at the 18 GHz electron cyclotron resonance ion source of the National Institute of Radiological Sciences. Rev Sci Instrum 2014; 85:02A931. [PMID: 24593510 DOI: 10.1063/1.4829735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The two-frequency heating technique was studied to increase the beam intensities of highly charged ions provided by the high-voltage extraction configuration (HEC) ion source at the National Institute of Radiological Sciences (NIRS). The observed dependences on microwave power and frequency suggested that this technique improved plasma stability but it required precise frequency tuning and more microwave power than was available before 2013. Recently, a new, high-power (1200 W) wide band-width (17.1-18.5 GHz) travelling-wave-tube amplifier (TWTA) was installed. After some single tests with klystron and TWT amplifiers the simultaneous injection of the two microwaves has been successfully realized. The dependence of highly charged ions (HCI) currents on the superposed microwave power was studied by changing only the output power of one of the two amplifiers, alternatively. While operating the klystron on its fixed 18.0 GHz, the frequency of the TWTA was swept within its full limits (17.1-18.5 GHz), and the effect of this frequency on the HCI-production rate was examined under several operation conditions. As an overall result, new beam records of highly charged argon, krypton, and xenon beams were obtained at the NIRS-HEC ion source by this high-power two-frequency operation mode.
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Affiliation(s)
- S Biri
- National Institute of Radiological Science (NIRS), 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan
| | - A Kitagawa
- National Institute of Radiological Science (NIRS), 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan
| | - M Muramatsu
- National Institute of Radiological Science (NIRS), 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan
| | - A G Drentje
- National Institute of Radiological Science (NIRS), 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan
| | - R Rácz
- Institute for Nuclear Research (ATOMKI), H-4026 Debrecen, Bem tér 18/c, Hungary
| | - K Yano
- Graduated School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - Y Kato
- Graduated School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - N Sasaki
- Accelerator Engineering Corporation (AEC), Inage, Chiba 263-0043, Japan
| | - W Takasugi
- Accelerator Engineering Corporation (AEC), Inage, Chiba 263-0043, Japan
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16
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Uchida T, Minezaki H, Ishihara S, Muramatsu M, Rácz R, Asaji T, Kitagawa A, Kato Y, Biri S, Drentje AG, Yoshida Y. Status of the Bio-Nano electron cyclotron resonance ion source at Toyo University. Rev Sci Instrum 2014; 85:02C317. [PMID: 24593654 DOI: 10.1063/1.4862212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In the paper, the material science experiments, carried out recently using the Bio-Nano electron cyclotron resonance ion source (ECRIS) at Toyo University, are reported. We have investigated several methods to synthesize endohedral C60 using ion-ion and ion-molecule collision reaction in the ECRIS. Because of the simplicity of the configuration, we can install a large choice of additional equipment in the ECRIS. The Bio-Nano ECRIS is suitable not only to test the materials production but also to test technical developments to improve or understand the performance of an ECRIS.
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Affiliation(s)
- T Uchida
- Bio-Nano Electronics Research Centre, Toyo University, Kawagoe 350-8585, Japan
| | - H Minezaki
- Graduate School of Engineering, Toyo University, Kawagoe 350-8585, Japan
| | - S Ishihara
- Graduate School of Engineering, Toyo University, Kawagoe 350-8585, Japan
| | - M Muramatsu
- National Institute of Radiological Sciences (NIRS), Chiba 263-8555, Japan
| | - R Rácz
- Institute for Nuclear Research (ATOMKI), H-4026 Debrecen, Hungary
| | - T Asaji
- Oshima National College of Maritime Technology, Yamaguchi 742-2193, Japan
| | - A Kitagawa
- National Institute of Radiological Sciences (NIRS), Chiba 263-8555, Japan
| | - Y Kato
- Graduate School of Engineering, Osaka University, Suita 565-0871, Japan
| | - S Biri
- Institute for Nuclear Research (ATOMKI), H-4026 Debrecen, Hungary
| | - A G Drentje
- National Institute of Radiological Sciences (NIRS), Chiba 263-8555, Japan
| | - Y Yoshida
- Bio-Nano Electronics Research Centre, Toyo University, Kawagoe 350-8585, Japan
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17
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Rácz R, Biri S, Juhász Z, Sulik B, Pálinkás J. Molecular and negative ion production by a standard electron cyclotron resonance ion source. Rev Sci Instrum 2012; 83:02A313. [PMID: 22380160 DOI: 10.1063/1.3662960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Molecular and negative ion beams, usually produced in special ion sources, play an increasingly important role in fundamental and applied atomic physics. The ATOMKI-ECRIS is a standard ECR ion source, designed to provide highly charged ion (HCI) plasmas and beams. In the present work, H(-), O(-), OH(-), O(2)(-), C(-), C(60)(-) negative ions and H(2)(+), H(3)(+), OH(+), H(2)O(+), H(3)O(+), O(2)(+) positive molecular ions were generated in this HCI-ECRIS. Without any major modification in the source and without any commonly applied tricks (such as usage of cesium or magnetic filter), negative ion beams of several μA and positive molecular ion beams in the mA range were successfully obtained.
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Affiliation(s)
- R Rácz
- Institute of Nuclear Research (ATOMKI), Bem tér 18/c, H-4026 Debrecen, Hungary.
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Abstract
The ECR ion source has been operating in ATOMKI (Debrecen) since 1996. During the past 15 years lots of minor and numerous major technical modifications have been carried out on the ECRIS. Many of these changes aimed the increasing of beams charge, intensity, and the widening of the ion choice. Another group of the modifications were performed to develop special, non-standard operation modes or to produce peculiar plasmas and beams.
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Affiliation(s)
- S Biri
- Institute of Nuclear Research (ATOMKI), H-4026 Debrecen, Bem tér 18∕c, Hungary.
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Rácz R, Biri S, Pálinkás J. Electron cyclotron resonance plasma photos. Rev Sci Instrum 2010; 81:02B708. [PMID: 20192448 DOI: 10.1063/1.3267289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In order to observe and study systematically the plasma of electron cyclotron resonance (ECR) ion sources (ECRIS) we made a high number of high-resolution visible light plasma photos and movies in the ATOMKI ECRIS Laboratory. This required building the ECR ion source into an open ECR plasma device, temporarily. An 8MP digital camera was used to record photos of plasmas made from Ne, Ar, and Kr gases and from their mixtures. We studied and recorded the effect of ion source setting parameters (gas pressure, gas composition, magnetic field, and microwave power) to the shape, color, and structure of the plasma. The analysis of the photo series gave us many qualitative and numerous valuable physical information on the nature of ECR plasmas.
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Affiliation(s)
- R Rácz
- Institute of Nuclear Research (ATOMKI), H-4026 Debrecen, Hungary.
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Tarr F, Sasvári M, Kayser S, Busman C, Rácz R. The nitric oxide „eluting“ internal mammary artery bypass graft and its remodelling effect on the recipient coronary tributary. Thorac Cardiovasc Surg 2007. [DOI: 10.1055/s-2007-967655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Sugár T, Nagy R, Rácz R, Busman C, Somogyi A, Kayser S, Tarr F. Changes in surgical strategy and techniques of our 10 years experiences with off pump coronary revascularisation. Thorac Cardiovasc Surg 2007. [DOI: 10.1055/s-2007-967632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Kovács GS, Fazakas S, Bogáts G, Rácz R. Measurement of resistance versus flow in assessing efficiency of aortocoronary bypass grafts. J Cardiovasc Surg (Torino) 1990; 31:571-3. [PMID: 2229150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Measurement of flow in saphenous bypass grafts with an electromagnetic flowmeter is complicated and poorly reproducible. Since coronary flow is largely dependent on variable factors the stable value of resistance seems more appropriate for comparison. A simple method has been developed for intraoperative measurement of resistance in the respective coronary bed. Pressure is recorded in the saphenous graft by an electromanometer during continuous flushing with known amounts of blood, and resistance is calculated instantaneously. The procedure is very simple and takes less than one minute. The quality of the saphenous vein itself can be assessed simultaneously by the same method. Resistances were measured during coronary surgery in over 500 saphenous grafts. The results were highly reproducible and comparable. Excellent flows can be expected if resistance is below 200 Peripheral Resistance Units (PRU); if this is over 800 PRU flow is very poor.
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Affiliation(s)
- G S Kovács
- Department of Cardiac Surgery, Albert Szent-Györgyi Medical University, Szeged, Hungary
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Rudas L, Fazakas S, Rácz R, Vajtai G, Kovács G. [The role of calcium antagonist withdrawal in perioperative coronary spasm]. Orv Hetil 1986; 127:807-11. [PMID: 3960525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Rácz R, Varga J. [Glycosylated hemoglobin as an index of the duration of hyperglycemia in diabetes mellitus patients]. Patol Fiziol Eksp Ter 1984:78-80. [PMID: 6483488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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