Development of a non-destructive depth-selective quantification method for sub-percent carbon contents in steel using negative muon lifetime analysis

Ninomiya, Kazuhiko*; Kubo, Kenya*; Inagaki, Makoto*; Yoshida, Go*; Chiu, I.-H. ; Kudo, Takuto*; Asari, Shunsuke*; Sentoku, Sawako*; Takeshita, Soshi*; Shimomura, Koichiro*; et al.

Scientific Reports (Internet), 14, p.1797_1 - 1797_8, 2024/01

https://doi.org/10.1038/s41598-024-52255-5

The amount of C in steel, which is critical in determining its properties, is strongly influenced by steel production technology. We propose a novel method of quantifying the bulk C content in steel non-destructively using muons. This revolutionary method may be used not only in the quality control of steel in production, but also in analyzing precious steel archaeological artifacts. A negatively charged muon forms an atomic system owing to its negative charge, and is finally absorbed into the nucleus or decays to an electron. The lifetimes of muons differ significantly, depending on whether they are trapped by Fe or C atoms, and identifying the elemental content at the muon stoppage position is possible via muon lifetime measurements. The relationship between the muon capture probabilities of C/Fe and the elemental content of C exhibits a good linearity, and the C content in the steel may be quantitatively determined via muon lifetime measurements. Furthermore, by controlling the incident energies of the muons, they may be stopped in each layer of a stacked sample consisting of three types of steel plates with thicknesses of 0.5 mm, and we successfully determined the C contents in the range 0.20 - 1.03 wt% depth-selectively, without sample destruction.

Decomposition studies of group 6 hexacarbonyl complexes, 1; Production and decomposition of Mo(CO) and W(CO)

Usoltsev, I.*; Eichler, R.*; Wang, Y.*; Even, J.*; Yakushev, A.*; Haba, Hiromitsu*; Asai, Masato; Brand, H.*; Di Nitto, A.*; Dllmann, Ch. E.*; et al.

Radiochimica Acta, 104(3), p.141 - 151, 2016/03

https://doi.org/10.1515/ract-2015-2445

Conditions of the production and decomposition of hexacarbonyl complexes of short-lived Mo and W isotopes were investigated to study thermal stability of the heaviest group 6 hexacarbonyl complex Sg(CO). A tubular flow reactor was tested to decompose the hexacarbonyl complexes and to extract the first bond dissociation energies. A silver was found to be the most appropriate reaction surface to study the decomposition of the group 6 hexacarbonyl. It was found that the surface temperature at which the decomposition occurred was correlated to the first bond dissociation energy of Mo(CO) and W(CO), indicating that the first bond dissociation energy of Sg(CO) could be determined with this technique.

Synthesis and detection of a Seaborgium carbonyl complex

Even, J.*; Yakushev, A.*; Dllmann, Ch. E.*; Haba, Hiromitsu*; Asai, Masato; Sato, Tetsuya; Brand, H.*; Di Nitto, A.*; Eichler, R.*; Fan, F. L.*; et al.

Science, 345(6203), p.1491 - 1493, 2014/09

https://doi.org/10.1126/science.1255720

A new superheavy element complex, a seaborgium carbonyl, has been successfully synthesized, and its adsorption property has been studied using a cryo-thermochromatography and -detection apparatus COMPACT. Nuclear reaction products of short-lived Sg preseparated with a gas-filled recoil ion separator GARIS at RIKEN were directly injected into a gas cell filled with He/CO mixture gas, and chemical reaction products of volatile carbonyl complexes were trasported to COMPACT. The Sg carbonyl complex detected with COMPACT was found to be very volatile with adsorption enthalpy of 50 kJ/mol, from which we have concluded that this complex should be a Sg hexacarbonyl Sg(CO). This is the first synthesis of organometallic compounds of transactinide elements for which only simple inorganic comounds have been synthesized so far.

Recent progress in the energy recovery linac project in Japan

Sakanaka, Shogo*; Akemoto, Mitsuo*; Aoto, Tomohiro*; Arakawa, Dai*; Asaoka, Seiji*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; et al.

Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.2338 - 2340, 2010/05

http://accelconf.web.cern.ch/AccelConf/IPAC10/papers/tupe091.pdf

Future synchrotron light source using a 5-GeV energy recovery linac (ERL) is under proposal by our Japanese collaboration team, and we are conducting R&D efforts for that. We are developing high-brightness DC photocathode guns, two types of cryomodules for both injector and main superconducting (SC) linacs, and 1.3 GHz high CW-power RF sources. We are also constructing the Compact ERL (cERL) for demonstrating the recirculation of low-emittance, high-current beams using above-mentioned critical technologies.

Experiments on synthesis of the heaviest element at RIKEN

Morita, Kosuke*; Morimoto, Koji*; Kaji, Daiya*; Akiyama, Takahiro*; Goto, Shinichi*; Haba, Hiromitsu*; Ideguchi, Eiji*; Kanungo, R.*; Katori, Kenji*; Kikunaga, Hidetoshi*; et al.

AIP Conference Proceedings 891, p.3 - 9, 2007/03

https://doi.org/10.1063/1.2713494

A series of experiments studying the productions and their decays of the heaviest elements have been performed by using a gas-filled recoil separator GARIS at RIKEN. Results on the isotope of the 112th element, 112, and on that of the 113th element, 113, are reviewed. Two decay chains which are assigned to be ones originating from the isotope 112 were observed in the Pb(Zn, n) reaction. The results provide a confirmation of the production and decay of the isotope 112 reported by a research group at GSI, Germany, produced via the same reaction by using a velocity filter. Two decay chains, both consisted of four consecutive alpha decays followed by a spontaneous fission, were observed also in the reaction Bi(Zn, n). Those are assigned to be the convincing candidate events of the isotope of the 113th element, 113, and its daughter nuclei. Rg, Mt, Bh, and Db.

Development Method to Estimate the Complex Index of Refraction of Dielectric Aerosols

Kudo, Kazuhiko*; Li, H.*; Li, B.-X.*; Saito, Jun*; Yamaguchi, Akira; Takata, Takashi

JSME International Journal, Series B, 47(3), p.631 - 636, 2004/08

A method to estimate complex refractive index of dielectric aerosols is developed. For the purpose, three-dimensional radiative transfer problem in an absorbing-scattering media is solved by the Monte Carlo method. The Mie.s scattering theory is used to handle particle scattering and absorption. Magnesium oxide aerosol, whose complex index of refraction is well known, is selected as the example of the dielectric aerosol. Magnesium is burnt to produce MgO aerosol and the transmission of the radiation from a black body furnace through the aerosol layer is measured. By comparing the analytical results of transmitted energy profile along the wall facing the emission resource, black body furnace, obtained for a wide range of the complex index of refraction, with the experimental results, it is shown that the value of the complex refractive index of the aerosol can be estimated.

Startup of transactinide chemistry in JAERI

Haba, Hiromitsu; Tsukada, Kazuaki; Asai, Masato; Nishinaka, Ichiro; Sakama, Minoru*; Goto, Shinichi*; Hirata, Masaru; Ichikawa, Shinichi; Nagame, Yuichiro; Kaneko, Tetsuya*; et al.

Radiochimica Acta, 89(11-12), p.733 - 736, 2002/02

https://doi.org/10.1524/ract.2001.89.11-12.733

no abstracts in English

Aqueous chemistry with seaborgium (element 106)

Brchle, W.*; Andrassy, M.*; Angert, R.*; Eberhardt, K.*; Fricke, B.*; Gregorich, K. E.*; Gnther, R.*; Hartmann, W.*; Heimann, R.*; Hoffman, D. C.*; et al.

1st International Conference on the Chemistry and Physics of the Transactinide Elements; Extended Abstracts, 4 Pages, 1999/00

no abstracts in English

Design and first integral test of MUSE facility in ALPHA program

H.Park*; ; Maruyama, Yu; Moriyama, Kiyofumi; Kudo, Tamotsu; Y.Yang.*; Sugimoto, Jun

JAERI-Tech 98-007, 62 Pages, 1998/03

JAERI-Tech-98-007.pdf:2.44MB

no abstracts in English

Reviews of experimental studies on various geometrical contact modes of vapor explosions

H.-S.Park*; Yamano, N.; Maruyama, Yu; Moriyama, Kiyofumi; Kudo, Tamotsu; Sugimoto, Jun

JAERI-Review 96-018, 46 Pages, 1996/11

JAERI-Review-96-018.pdf:1.99MB

no abstracts in English