Flow peak detection using penalized asymmetric least squares in on-line isotope dilution-laser ablation-inductively coupled plasma-mass spectrometry

Yanagisawa, Kayo; Yokota, Hiromi*; Fujimoto, Katsushige*; Takagai, Yoshitaka*

Bunseki Kagaku, 73(9), p.515 - 522, 2024/09

On-line isotope dilution-laser ablation-inductively coupled plasma-mass spectrometry (on-line ID-LA-ICP-MS) is capable of quantification for each point ablated by laser, then the quantitative mapping of elements can be also conducted by reconstruction of the obtained each point data. The volume of data obtained as flow peaks in this system as a flow injection analysis, will be multiplied by each data such as number of m/z, scan time, time resolution and measurement position, and the total amount of data is enormous, resulting in a large human power and time consumption for data processing. In this paper, an original application software using Python to improve the efficiency of data processing in on-line ID-LA-ICP-MS was developed. To discriminate between the time-to-peak intensity and the background noise, an automatic peak detection using penalized asymmetric least squares was developed.

Research on radioactive aerosol control and decontamination at Fukushima Daiichi Nuclear Power Station Decommissioning (Contract research); FY2022 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; The University of Tokyo*

JAEA-Review 2024-031, 75 Pages, 2024/08

JAEA-Review-2024-031.pdf:3.74MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2022. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2021, this report summarizes the research results of the "Research on radioactive aerosol control and decontamination at Fukushima Daiichi Nuclear Power Station decommissioning" conducted in FY2022. The present study aims to develop a safe laser decontamination system that can control aerosol diffusion during laser decontamination while simultaneously allowing advanced particle measurement and evaluation, in cooperation with a research group in the United Kingdom.

Single-shot laser-driven neutron resonance spectroscopy for temperature profiling

Lan, Z.*; Arikawa, Yasunobu*; Mirfayzi, S. R.*; Morace, A.*; Hayakawa, Takehito*; Sato, Hirotaka*; Kamiyama, Takashi*; Wei, T.*; Tatsumi, Yuta*; Koizumi, Mitsuo; et al.

Nature Communications (Internet), 15, p.5365_1 - 5365_7, 2024/07

https://doi.org/10.1038/s41467-024-49142-y

Stochastic ray tracing for Fresnel diffraction

Seto, Keita

Optics Express (Internet), 32(10), p.16999 - 17011, 2024/05

https://doi.org/10.1364/OE.521317

Analysis of gadolinium oxide using microwave-enhanced fiber-coupled micro-laser-induced breakdown spectroscopy

Ikeda, Yuji*; Soriano, J. K.*; Oba, Hironori; Wakaida, Ikuo

Scientific Reports (Internet), 13, p.4828_1 - 4828_9, 2023/03

https://doi.org/10.1038/s41598-023-32146-x

Development of the continuous monitoring of tritium water by mid-infrared laser spectroscopy (Contract research); FY2021 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; National Institutes of Natural Sciences*

JAEA-Review 2022-059, 34 Pages, 2023/01

JAEA-Review-2022-059.pdf:1.58MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2021. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2021, this report summarizes the research results of the "Development of the continuous monitoring of tritium water by mid-infrared laser spectroscopy" conducted in FY2021. The present study aims to demonstrate the principle of short-time measurement of tritiated water at the "60 Bq/cc level" using a cavity ring-down measurement system with a mid-infrared laser. In order to achieve the above goal, (1) research on the cavity ring-down system and (2) evaluation of hydrogen isotope composition under environmental conditions and preparation of standard samples (subcontractor: Hirosaki University) were conducted this fiscal year. In (1), a mid-infrared cavity ring-down test was conducted. An optical bench (3 m 1.2 m) was set up in the laboratory, …

Instability phenomena of lean hydrogen/oxygen/inert-gas premixed flames on a flat burner

Katsumi, Toshiyuki; Thwe Thwe, A.; Kadowaki, Satoshi

Journal of Visualization, 25(5), p.1075 - 1083, 2022/10

https://doi.org/10.1007/s12650-022-00844-9

Lean combustion and inert-gas addition are useful to control the burning velocity of hydrogen premixed flames, and it is well known that the cellular structure forms on the front of lean hydrogen flames owing to intrinsic instability. However, the influences of inert-gas addition on the instability phenomena of lean hydrogen premixed flames are not understood fully, and then it is needed to be investigated the flame instability experimentally. In the experiments, the cellular structure and fluctuation of H/O/inert gases (Ar, N,CO) premixed flames on a flat burner were obtained using direct observation, laser diagnostics and light emission intensity to elucidate the characteristics of instability phenomena. As the results, the correlation of inert-gas addition, equivalence ratio and total flow rate with the characteristics of cellular flames was revealed, and the influences of these parameters on flame instability were discussed.

Analysis of microparticles generated by laser processing and development of a methodology for their nuclear identification (Contract research); FY2020 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; The University of Tokyo*

JAEA-Review 2022-015, 119 Pages, 2022/09

JAEA-Review-2022-015.pdf:6.62MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2020. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2018, this report summarizes the research results of the "Analysis of microparticles generated by laser processing and development of a methodology for their nuclear identification" conducted from FY2018 to FY2021 (this contract was extended to FY2021). Since the final year of this proposal was FY2021, the results for four fiscal years were summarized. Although laser processing has various advantages, one well-known disadvantage is that it generates a large amount of microparticles during the processing. Therefore, the application of laser processing to decommissioning waste contaminated with radioactive materials has been hesitant because the mechanism generating the microparticles has not been fully understood.

Novel Sr analysis of environmental samples by ion-laser interaction mass spectrometry

Honda, Maki; Martschini, M.*; Marchhart, O.*; Priller, A.*; Steier, P.*; Golser, R.*; Sato, Tetsuya; Tsukada, Kazuaki; Sakaguchi, Aya*

Analytical Methods, 14(28), p.2732 - 2738, 2022/07

https://doi.org/10.1039/D2AY00604A

The sensitive Sr analysis with accelerator mass spectrometry (AMS) was developed for the advances of environmental radiology. One advantage of AMS is the ability to analyze various environmental samples with Sr/Sr atomic ratios of 10 in a simple chemical separation. Three different IAEA samples with known Sr concentrations (moss-soil, animal bone, Syrian soil: 1 g each) were analyzed to assess the validity of the chemical separation and the AMS measurement. The Sr measurements were conducted on the AMS system combined with the Ion Laser InterAction MasSpectrometry (ILIAMS) setup at the University of Vienna, which has excellent isobaric separation performance. The isobaric interference of Zr in the Sr AMS was first removed by chemical separation. The separation factor of Zr in two-step column chromatography with Sr resin and anion exchange resin was 10. The Zr remaining in the sample was removed by ILIAMS effectively. This simple chemical separation achieved a limit of detection 0.1 mBq in the Sr AMS, which is lower than typical -ray detection. The agreement between AMS measurements and nominal values for the Sr concentrations of IAEA samples indicated that the new highly-sensitive Sr analysis in the environmental samples with AMS is reliable even for high matrix samples of soil and bone.

Developing accelerator mass spectrometry capabilities for anthropogenic radionuclide analysis to extend the set of oceanographic tracers

Hain, K.*; Martschini, M.*; Glce, F.*; Honda, Maki; Lachner, J.*; Kern, M.*; Pitters, J.*; Quinto, F.*; Sakaguchi, Aya*; Steier, P.*; et al.

Frontiers in Marine Science (Internet), 9, p.837515_1 - 837515_17, 2022/03

https://doi.org/10.3389/fmars.2022.837515

Recent major advances in accelerator mass spectrometry (AMS) at the Vienna Environmental Research Accelerator (VERA) regarding detection efficiency and isobar suppression have opened possibilities for the analysis of additional long-lived radionuclides at ultra-low environmental concentrations. These radionuclides, including U, Cs, Tc and Sr, will become important for oceanographic tracer application due to their generally conservative behavior in ocean water. In particular, the isotope ratios U/U and Cs/Cs have proven to be powerful fingerprints for emission source identification as they are not affected by elemental fractionation. Improved detection efficiencies allowed us to analyze all major long-lived actinides, i.e. U, Np, Pu, Am as well as the very rare U, in the same 10 L water samples of an exemplary depth profile from the northwest Pacific Ocean. Especially for Sr analysis, our new approach has already been validated for selected reference materials (e.g. IAEA-A-12) and is ready for application in oceanographic studies. We estimate that a sample volume of only (1-3) L ocean water is sufficient for Sr as well as Cs analysis, respectively.