Akihito Mochizuki

幌延深地層研究計画 令和8年度調査研究計画

Masashi Nakayama, Eiichi Ishii, Kazuhei Aoyagi, Akira Hayano et autres

The Horonobe Underground Research Laboratory Project is being pursued by the Japan Atomic Energy Agency to enhance the reliability of relevant technologies for geological disposal of high-level radioactive waste through investigating the deep geological environment within the host sedimentary rocks at Horonobe …

Biogeochemical behavior of particulate elements in the Hövsgöl‒Ustilimsk water system in Mongolia and Russia

Ko Hosoda, Takahiro Murata, Akihito Mochizuki, Toshiya Katano et autres

jp, mn, ru (code pays fourni par la source)

Uranium behavior and redox environment in surface water and deep groundwater

Akihito Mochizuki

酸化的な湖沼・河川などの地表水，および還元的な湖沼深部・地下水を対象に，ウラン（U）の化学状態や動態に関する知見を整理した。炭酸イオンやカルシウムイオンとの錯体形成，固相表面への吸脱着反応，酸化還元反応にともなう価数変化などが，Uの挙動や移動性に大きく影響する。特に，炭酸化学種濃度が高く還元的な環境では，U(VI)-炭酸錯体の形成やU(IV) への還元反応の抑制により，Uの溶解度や移動性の低下が生じにくくなる可能性がある。また，Uをはじめとする酸化還元に鋭敏な元素の化学状態や移動性を支配する要因の一つとして地下水の酸化還元状態に着目し，その測定・評価手法や，地下深部における坑道掘削にともなう擾乱の影響について，筆者らの研究成果を交えて概説した。

jp (code pays fourni par la source)

幌延深地層研究計画 令和6年度調査研究成果報告

Masashi Nakayama, Eiichi Ishii, Kazuhei Aoyagi, Akira Hayano et autres

The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant technologies for geological disposal of high-level radioactive waste through investigating the deep geological environment within the host sedimentary rocks …

幌延深地層研究計画 令和7年度調査研究計画

Masashi Nakayama, Eiichi Ishii, Akira Hayano, Kazuhei Aoyagi et autres

The Horonobe Underground Research Laboratory Project is being pursued by the Japan Atomic Energy Agency to enhance the reliability of relevant technologies for geological disposal of high-level radioactive waste through investigating the deep geological environment within the host sedimentary rocks at Horonobe …

jp, us, ru (code pays fourni par la source)

Long-term changes in the chemical, microstructural, and transport properties of a low-pH cement shotcrete during operation of the Horonobe Underground Research Laboratory, Japan

Akihito Mochizuki, Hiroya Matsui, Masashi Nakayama, Ryo Sakamoto et autres

The properties of low-pH cement used in the geological disposal of radioactive waste may change through atmospheric carbonation and degradation caused by groundwater during the long-term operation of a repository. In this study, we investigated the effects of atmospheric carbonation and groundwater …

jp (code pays fourni par la source)

Diverse microbiome functions, limited temporal variation and substantial genomic conservation within sedimentary and granite rock deep underground research laboratories

Yuki Amano, Rohan Sachdeva, Daniel A. Gittins, Karthik Anantharaman et autres

Underground research laboratories (URLs) provide a window on the deep biosphere and enable investigation of potential microbial impacts on nuclear waste, CO 2 and H 2 stored in the subsurface. We carried out the first multi-year study of groundwater microbiomes sampled from …

jp, us (code pays fourni par la source)

Rapid and long-lasting bedrock flow-path sealing by a ‘concretion-forming resin’: results from in situ evaluation tests in an underground research laboratory, Horonobe, Japan

Hidekazu Yoshida, Koshi Yamamoto, Yoshihiro Asahara, Ippei Maruyama et autres

A capability to permanently seal fluid flow paths in bedrock, such as natural faults/fractures, and damaged zones around boreholes/excavations, is needed to ensure the long-term safety and effectiveness of many underground activities. Cementitious materials are commonly used as seals, but these materials …

jp, gb (code pays fourni par la source)

Post-earthquake rapid resealing of bedrock flow-paths by concretion-forming resin

Hidekazu Yoshida, Koshi Yamamoto, Yoshihiro Asahara, Ippei Maruyama et autres

Abstract Many underground activities may require reducing or preventing fluid flows through bedrock, e.g., sealing of site investigation boreholes, underground tunneling, hydrocarbon field abandonment, and nuclear waste disposal. Cementitious materials such as grout are commonly used for bedrock flow-path sealing, however conventionally …

jp, gb (code pays fourni par la source)

Characterization of sediment and granite hosted deep underground research laboratories reveals diverse microbiome functions, limited temporal variation and substantial genomic conservation

Yuki Amamo, Rohan Sachdeva, Daniel A. Gittins, Karthik Anantharaman et autres

Underground research laboratories (URLs) provide a window on the deep biosphere and enable investigation of potential microbial impacts on nuclear waste, CO2 and H2 stored in the subsurface. We carried out the first multi-year study of groundwater microbiomes sampled from defined intervals …

jp, us (code pays fourni par la source)

Paleohydrogeology of the Horonobe area, Northern Hokkaido, Japan: Groundwater flow conditions during glacial and postglacial periods estimated from chemical and isotopic data for fracture and pore water

Akihito Mochizuki, Eiichi Ishii

jp (code pays fourni par la source)

Numerical reproduction of the seasonal variation in dissolved uranium in Lake Biwa

Tatsuo Saito, Hiromi Yamazawa, Akihito Mochizuki

jp (code pays fourni par la source)