Evaluation of photonuclear reaction cross-section data for Bi at 13 and 17 MeV photon energies

Nguyen, T. T. H.*; Iwamoto, Nobuyuki; Sanami, Toshiya*

JAEA-Conf 2024-002, p.139 - 143, 2024/11

https://doi.org/10.11484/jaea-conf-2024-002

Extraction of Mo hot atoms made by a neutron capture method from -MoO to water

Quach, N. M.*; Ngo, M. C.*; Yang, Y.*; Nguyen, T. B.*; Nguyen, V. T.*; Fujita, Yoshitaka; Do, T. M. D.*; Nakayama, Tadachika*; Suzuki, Tatsuya*; Suematsu, Hisayuki*

Journal of Radioanalytical and Nuclear Chemistry, 332(10), p.4057 - 4064, 2023/10

https://doi.org/10.1007/s10967-023-09125-7

Technetium-99m (Tc) is the most widely used medical radioisotope in the world and is produced from molybdenum-99 (Mo). Production of Mo via the neutron capture method draws attention as an alternative to fission-derived Mo due to non-proliferation issues, but the specific radioactivity of Mo is extremely low. In this work, a porous -MoO wire was prepared as an irradiation target in order to improve the specific activity by extracting Mo. Porous -MoO wire is synthesized from Mo metal wire by a two-step heating procedure. The hot atom effect of Mo was confirmed by activity and isotope measurements of the porous -MoO wire after neutron irradiation and the water used for extraction. In term of the extraction effectiveness, the effectiveness of Mo extraction in the porous -MoO wire was comparable to that of commercial -MoO powder.

Selective recovery of thorium and uranium from leach solutions of rare earth concentrates in continuous solvent extraction mode with primary amine N1923

Nguyen, T. H.*; Le Ba, T.*; Tran, C. T.*; Nguyen, T. T.*; Doan, T. T. T.*; Do, V. K.; Watanabe, Masayuki; Pham, Q. M.*; Hoang, S. T.*; Nguyen, D. V.*; et al.

Hydrometallurgy, 213, p.105933_1 - 105933_11, 2022/08

https://doi.org/10.1016/j.hydromet.2022.105933

A continuous counter-current extraction for the selective recovery of thorium (Th) and uranium (U) from the Yen Phu (Vietnam) rare earth concentrate leach solutions was systematically studied. The primary amine N1923 was used as an extractant which was prepared in the isoparaffin IP-2028 diluent. Thorium and uranium were selectively recovered in a hydrometallurgical circuit established by continuous mixer-settler extraction, scrubbing, and back-extraction at the laboratory scale. The desired purity of Th and U can be achieved by managing the volume ratio of organic to aqueous phase (O/A ratio) in the corresponding steps. Highly pure Th and U were recovered from the pregnant back-extraction liquor and the raffinate, respectively, which have satisfactory properties for further processing of the subsequent nuclear materials.

Progress of ultra-high-speed image sensors with in-situ CCD storage

Eto, Takeharu*; Dao, V. T. S.*; Nguyen, H. D.*; Fife, K.*; Kureta, Masatoshi; Segawa, Mariko; Arai, Masatoshi; Shinohara, Takenao

Proceedings of 2011 International Image Sensor Workshop (IISW), 4 Pages, 2011/06

http://www.imagesensors.org/Past%20Workshops/2011%20Workshop/2011%20Papers/R57_Etoh_HighSpeedCCD.pdf

This paper reviews progress of technologies on ultra-high-speed image sensors with in-situ CCD signal storage. The CCD storage for each pixel has more than one hundred CCD memory elements. Simultaneous parallel recording of signals at all pixels enables ultra-high-speed capturing of consecutive images.

Small-sized human immunodeficiency virus type-1 protease inhibitors containing allophenylnorstatine to explore the S2' pocket

Hidaka, Koshi*; Kimura, Toru*; Abdel-Rahman, H. M.*; Nguyen, J.-T.*; McDaniel, K. F.*; Kohlbrenner, W. E.*; Molla, A.*; Adachi, Motoyasu; Tamada, Taro; Kuroki, Ryota; et al.

Journal of Medicinal Chemistry, 52(23), p.7604 - 7617, 2009/07

https://doi.org/10.1021/jm9005115

A series of HIV protease inhibitor based on the allophenylnorstatine structure with various P2' moieties were synthesized. Among these analogues, we discovered that a small allyl group would maintain potent enzyme inhibitory activity compared to that of the -methylbenzyl moiety in clinical candidate 1 (KNI-764, also known as JE-2147, AG-1776 or SM-319777). Introduction of an anilinic amino group to 2 (KNI-727) improved water-solubility and anti-HIV-1 activity. X-ray crystallographic analysis of 13k (KNI-1689) with a -methallyl group at P2' position revealed hydrophobic interactions with Ala28, Ile84, and Ile50' similar to that of 1. The presence of an additional methyl group on the allyl group in compound 13k significantly increased anti-HIV activity over 1, while providing a rational drug design for structural minimization and improving membrane permeability.

Solvent extraction of palladium(II) with various ketones from nitric acid medium

Nguyen, H. T.; Watanabe, Masayuki; Kimura, Takaumi

Solvent Extraction and Ion Exchange, 25(3), p.407 - 416, 2007/00

https://doi.org/10.1080/07366290701285538

Solvent extraction of Pd(II) with various ketones in nitrobenzene from nitric acid medium was investigated. In this study, seventeen commercially available ketones were selected as representatives of alkyl ketones. It was found that several ketones effectively extracted Pd(II) from nitric acid medium. Methylalkylketones, such as 2-octanone, 2-nonanone, 2-undecanone, 2-tridecanone, and ketones containing symmetrical alkyl configuration, such as 5-nonanone, 5-decanone, 5-undecanone and 6-undecanone exhibited significant extraction of Pd(II) from nitric acid. Particularly, 2-tridecanone and 2-nonanone showed efficient extractability for Pd(II) and their extraction behavior was fully vestigated. With these extractants the partitioning of Pd(II) to the organic phase was significant at a ligand concentration of 3.0 M and acidity above 2.0 M.

Spectroscopic analyses on iron and rare earths in Yen Phu mine

Aoyagi, Noboru; Nakada, Masami; Kumagai, Yuta; Watanabe, Masayuki; Nguyen, T. T.*; Nguyen, V. T.*; Nguyen, T. H.*; Le, B. T.*

no journal, , 

Mineral characterization of rare earth-containing ores from Yen Phu mine, Vietnam, was performed using microscopic and spectroscopic techniques, namely SEM-EDX, Mssbauer spectroscopy, FT-IR microscopy, and time-resolved laser-induced fluorescence spectroscopy. Mssbauer spectra indicate the formation of magnetite-like, hematite-like, and iron(III) salt in common with three ores sampled at different points in the mine. Around the grain boundary in the magnetite-like mineral phase the presence of phosphate band was confirmed by IR spectroscopy in the magnetite-like mineral phase. The chemical state of the rare earth species has not been obtained through these methods. However, the finding for Eu analysis from the result of TRLFS suggests that the Eu species are identical in the different matrices of iron oxides.

Isotope production using novel MoO targets; Contribution by vietnamese institutes, staffs and students

Suematsu, Hisayuki*; Ngo, M. C.*; Quach, N. M.*; Fujita, Yoshitaka; Do, T. M. D.*; Nakayama, Tadachika*; Suzuki, Tatsuya*; Nguyen, V. T.*; Niihara, Koichi*

no journal, , 

Radiopharmacies have been used in various medical diagnoses/therapies and their market has been growing by ten times in fifteen years. In particular, Tc has been widely used in gamma ray diagnoses. Mo, the raw material for Tc, is currently produced as a fission product by irradiating highly enriched uranium in nuclear reactors. Efforts are being made worldwide to reduce the use of uranium from the perspective of nuclear non-proliferation. A Mo(n,)Mo reaction in low enriched uranium reactors can be an alternative method. In this research, we revealed that -MoO, a low-temperature phase of MoO, as a neutron irradiation target promotes the diffusion of Mo from the target to water due to the hot atom effect. Utilizing this phenomenon can contribute to the stable supply of Mo and Tc. The first nuclear reaction in/water dispersion experiments using an -MoO powder target was carried out in Dalat Nuclear Reactor, Vietnam Atomic Energy Institute to show the hot atom effect. Then, the water recovery efficiency was dramatically improved using a novel -MoO whisker target by Vietnamese students and staffs. Their contributions to this research will be explained in the presentation.

Photonuclear data evaluation considering experimental double differential cross-sections

Thi Hong Nguyen, T.*; Iwamoto, Nobuyuki; Sanami, Toshiya*

no journal, ,