Mass Transport of Multicomponents Solute in Bentonite Clay

2000 ◽  
Vol 663 ◽  
Author(s):  
Y. Ichikawa ◽  
K. Kawamura ◽  
M. Nakano ◽  
K. Kitayama ◽  
N. Saito ◽  
...  
Keyword(s):  
Md Simulation ◽  
Chemical Species ◽  
Bentonite Clay ◽  
Diffusion Problem ◽  
Radioactive Waste Disposal ◽  
Inhomogeneous Material ◽  
Solute Diffusion ◽  
Diffusion Behavior ◽  
Molecular Behavior ◽  
High Level

ABSTRACTA fundamental concept combining a molecular behavior and macro-continuum phenomenon is presented for a multicomponent solute diffusion problem in bentonite clay, which is a key component of the Engineering Barrier System (EBS) of high-level radioactive waste disposal (HLRW). Bentonite is a micro-inhomogeneous material. Properties of the saturated bentonite are characterized by the constituent clay mineral (montmorillonite) and water, namely montmorillonite hydrate. We analyze its molecular behavior by applying a molecular dynamics (MD) simulation to inquire into the physicochemical properties such as diffusivity of chemical species. For extending the microscopic characteristics of constituent materials to a macroscopic diffusion behavior of the micro-inhomogeneous material we apply a homogenization analysis (HA).

Properties of Bentonite Clay as Buffer Material in High-Level Waste Geological Disposal. Part I: Chemical Species Contained in Bentonite

1987 ◽  
Vol 76 (2) ◽  
pp. 221-228 ◽  
Author(s):  
Masanori Takahashi ◽  
Masayuki Muroi ◽  
Atsuyuki Inoue ◽  
Masahiro Aoki ◽  
Makoto Takizawa ◽  
...  
Keyword(s):  
Chemical Species ◽  
Bentonite Clay ◽  
High Level Waste ◽  
Geological Disposal ◽  
Buffer Material ◽  
High Level

scholarly journals EXPERIMENTAL STUDY ON MANUFACTURE OF BLOCK-TYPE BUFFER FOR HIGH-LEVEL RADIOACTIVE WASTE DISPOSAL

2003 ◽  
pp. 203-208
Author(s):  
Hideo KOMINE ◽  
Nobuhide OGATA ◽  
Akira NAKASHIMA ◽  
Hajime TAKAO ◽  
Hiroyoshi UEDA ◽  
...  
Keyword(s):  
Experimental Study ◽  
Radioactive Waste ◽  
Waste Disposal ◽  
Radioactive Waste Disposal ◽  
Block Type ◽  
High Level Radioactive Waste ◽  
High Level

Investigation and Study on Environmental Radioactive Background in Xinchang and Jijicao Rock of Beishan Preselected Region for HLW Disposal Repository in China

2013 ◽  
Vol 726-731 ◽  
pp. 869-876
Author(s):  
Guo Hua Qiu
Keyword(s):  
Background Radiation ◽  
Environmental Radioactivity ◽  
Radioactive Waste Disposal ◽  
Natural Background ◽  
Local Resident ◽  
Natural Background Radiation ◽  
The Public ◽  
Environmental Investigation ◽  
High Level ◽  
Investigation And Study

On the basis of field environmental investigation and monitoring, the environmental radioactivity background of Xinchang and Jijicao rock in Beishan preselected region has been preliminary investigated and studied, and the public dose from local natural background radiation is estimated which can provide basic data and information for environmental impact assessment and safety assessment of HLW(the high level radioactive waste) disposal repository in the future. From the result of investigation and study, the environmental radioactivity of Xinchang and Jijicao rock is generally within normal natural background. The effective dose to local resident from natural background radiation is 2.110 mSv/a by internal and external exposure.

scholarly journals Thermal Conductivity of Compacted GO-GMZ Bentonite Used as Buffer Material for a High-Level Radioactive Waste Repository

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Yong-Gui Chen ◽  
Xue-Min Liu ◽  
Xiang Mu ◽  
Wei-Min Ye ◽  
Yu-Jun Cui ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Radioactive Waste ◽  
Water Content ◽  
Radioactive Waste Disposal ◽  
Dry Density ◽  
Gmz Bentonite ◽  
High Level Radioactive Waste ◽  
Buffer Material ◽  
High Level ◽  
Crucial Parameter

In China, Gaomiaozi (GMZ) bentonite serves as a feasible buffer material in the high-level radioactive waste (HLW) repository, while its thermal conductivity is seen as a crucial parameter for the safety running of the HLW disposal. Due to the tremendous amount of heat released by such waste, the thermal conductivity of the buffer material is a crucial parameter for the safety running of the high-level radioactive waste disposal. For the purpose of improving its thermal conductivity, this research used the graphene oxide (GO) to modify the pure bentonite and then the nanocarbon-based bentonite (GO-GMZ) was obtained chemically. The thermal conductivity of this modified soil has been measured and investigated under various conditions in this study: the GO content, dry density, and water content. Researches confirm that the thermal conductivity of the modified bentonite is codetermined by the three conditions mentioned above, namely, the value of GO content, dry density, and water content. Besides, the study proposes an improved geometric mean model based on the special condition to predict the thermal conductivity of the compacted specimen; moreover, the calculated values are also compared with the experimental data.

TOPOLOGICAL INDICES – WHY AND HOW

2021 ◽  
Author(s):  
Ivan Gutman ◽  
Keyword(s):  
Single Molecule ◽  
Chemical Structure ◽  
Chemical Reactivity ◽  
Chemical Species ◽  
Chemical Compounds ◽  
Simple Calculation ◽  
Topological Indices ◽  
High Level ◽  
Complex Phenomena ◽  
Real World Problems

By means of presently available high-level computational methods, based on quantum theory, it is possible to determine (predict) the main structural, electronic, energetic, geometric, and thermodynamic properties of a particular chemical species (usually a molecule), as well as the ways in which it changes in chemical reactions. When one needs to estimate such properties of thousands or millions of chemical species, such high-level calculations are no more feasible. Then simpler, but less accurate, approaches are necessary. One such approach utilized so-called “topological indices”. According to IUPAC ‘s definition [Pure Appl. Chem. 69 (1997) 1137]: A topological index is a numerical value associated with chemical constitution for correlation of chemical structure with various physical properties, chemical reactivity or biological activity. In the first part of the lecture, we show that „numerical values“are associated with many other complex phenomena, encountered in various areas of human activity, implying that „topological indices“ are used far beyond chemistry. Next, we discuss the number of possible chemical compounds. Simple calculation shows that the number of possible compounds zillion times exceeds the number of those that have been experimentally characterized. Even worse, in the entire Universe, there is not enough matter to make at least a single molecule of each possible compound. In the second part of the lecture, a few most popular topological indices will be presented, as well as the way in which these can be (and are being) applied in treating real-world problems.

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