JOPSS - Search Results

Journal Articles

Nuclear spin conversion of hydrogen and methane molecules inside low-temperature condensed layers

Yamakawa, Koichiro

Bunko Kenkyu, 72(5), p.187 - 198, 2023/10

Molecules including hydrogen nuclei in the rotationally symmetric positions are classified into the nuclear spin isomers, according to their resultant spin. Owing to the symmetry restriction originating from the indistinguishability of the identical particles, each isomer occupies only specific rotational levels. The conversion between the isomers is promoted in condensed systems, where the excess rotational energy of a converting molecule is dissipated. In this review, I focus on the fundamental molecules of hydrogen and methane, and expound studies on their nuclear spin conversion inside condensed layers at low temperatures.

Journal Articles

Application of vibrational sum frequency generation spectroscopy to studies of chemical reactions on water surface and actinide interface chemistry

Kusaka, Ryoji

Bunko Kenkyu, 72(4), p.155 - 162, 2023/08

Vibrational sum frequency generation (VSFG) spectroscopy is an optical second-order nonlinear vibrational spectroscopy using ultrashort pulse lasers. Because VSFG spectroscopy is a unique and powerful tool for studying molecular structures of interfaces, it has been widely used in many research fields. However, there still undoubtedly remains some VSFG research areas that have not studied well, partly because VSFG measurements are not so easily performed in comparison with relatively general spectroscopy methods. This review presented recent applications of VSFG spectroscopy to two research topics: (1) chemical reactions on water surfaces, and (2) actinide chemistry.

Journal Articles

Development of apparatus for in-situ terahertz and infrared spectroscopy

Yamakawa, Koichiro; Nasu, Hirokazu*; Shimizu, Genki*

Bunko Kenkyu, 69(3), p.105 - 106, 2020/06

Terahertz and infrared spectroscopy is one of the powerful ways to elucidate the structures and vibrational modes of molecular clusters. We review an experimental apparatus for absorption spectroscopy in an ultra-high vacuum covering the wavenumber range of 60-7000 cm $^{-1}$ , from the viewpoints of vacuum-, low-temperature-, and spectroscopy-techniques. We also introduce the terahertz and infrared spectrum of D $_{2}$ O clusters isolated in an Ar matrix measured with this apparatus.

Journal Articles

A Spectroscopic technique for analysis developed in the field of unclear energy

Kusaka, Ryoji

Bunko Kenkyu, 67(6), p.239 - 240, 2018/12

A spectroscopic technique for analysis developed by collaboration between Japan Atomic Energy Agency (JAEA) and Quantum and Radiological Science and Technology (QST) is discussed for readers outside the field of nuclear energy. This paper introduces a quantitative analysis for $^{107}$ Pd radioisotope contained in a spent nuclear fuel by using laser-induced photoreduction and inductively coupled plasma mass spectrometry (ICP-MS). The importance and problems of quantitative analysis for radioisotopes in spent nuclear fuels are described, and the principle, advantages, and future applications of the spectroscopic technique are discussed.

Journal Articles

Current status and future developments of hard X-ray photoelectron spectroscopy

Kobata, Masaaki; Okane, Tetsuo; Kobayashi, Keisuke*

Bunko Kenkyu, 67(4), p.161 - 162, 2018/08

We introduce hard X-ray photoelectron spectroscopy, which has been rapidly introduced and developed in synchrotron radiation facilities. In particular, in order to realize electronic state analysis by hard X-ray photoelectron spectroscopy of insulators, the developed charge neutralization method was described. As an example, we showed adsorption behavior of cesium to nuclear reactor structure assuming Fukushima Daiichi Nuclear Power Plant accident. Finally, future prospects of hard X-ray photoelectron spectroscopy will be described.

Journal Articles

The Structure, property and applications of defect fluorite oxides; Mssbauer, EXAFS and NMR studies coupled with new defect-crystal-chemistry model

Nakamura, Akio

Mesubaua Bunko Kenkyu, (14), p.8 - 11, 2013/00

I have recently proposed a new defect-crystal-chemistry model for coupled non-Vegardianity and non-random defect structure of so-called defect-fluorite oxides. In this lecture, I would like to give its review, emphasizing the importance of microscopic Mssbauer, EXAFS and NMR local-structure data in combination with XRD lattice parameter data.

Journal Articles