Fast neutron radiography (FNR) offers significant advantages for the nondestructive testing of large-scale and high-density materials. However, the presence of scattered neutrons results in image blurring and distortion, which severely compromises both the imaging quality and the accuracy of quantitative analysis. This study employed the Geant4 Monte Carlo code to simulate the point scattered function (PScF) data. A Gaussian model was subsequently applied to fit the obtained data, with particular emphasis on two key parameters of Maximum and full width at half maximum (FWHM). The effects of sample thickness and detection distance on the PScF parameters were systematically investigated for three typical materials of iron (Fe), tungsten (W) and polyethylene (PE). Through curve-fitting procedures, analytical expressions were derived to characterize the relationships of Maximum and FWHM with respect to sample thickness and detection distance, thereby enabling the rapid calculation of the PScF for any given set of parameters. The developed PScF model was utilized to perform scattering correction on fast neutron images obtained by Geant4 simulations. The results indicate that this method can effectively suppresses the scattered neutron component, leading to a remarkable enhancement in image quality and quantitative analysis accuracy, which validates the effectiveness of the proposed method.
LIAO Yixiang1, 2, GUO Hao1, 3, CAO Weijun1, 2, YAN Jiaqing1, 2, MAO Chuyuan1, 2, ZHANG Haitao1, 2, LI Chongwei4, WU Zhengxin1, 2, YAN Qiang1, 2, LIU Yong1, 2, LIU Guoqing1, 2,
With the development of science and technology, all kinds of nuclear radiation rays are more widely used, and the demand for radiation protection is also increasing. Moreover, with the deepening of radiation protection application scenarios, radiation protection materials need good environmental adaptability, mobility and wearability. Therefore, in this paper, two kinds of neutron/gamma composite shielding materials, B4C/Bi/NR and Gd2O3/Bi/NR, were prepared by using natural rubber, which has excellent mechanical properties, as the matrix, bismuth as the gamma-ray shielding body, and boron carbide (B4C) and gadolinium oxide (Gd2O3) as neutron-absorbing materials, respectively. A neutron test device was built with 252Cf as neutron source and 3He counting tube as detector to investigate the neutron shielding performance of the shielding materials, and the experimental results were verified by MCNP (Monte Carlo N Particle Transport Code), while the 252Cf shielding performance of the composite shielding materials was investigated by using MCNP simulation. High-purity germanium (HPGe) detector and universal testing machine were used for gamma shielding performance test and mechanical properties test, to study the filler type (B4C and Gd2O3) and filler content on the composite shielding material gamma shielding performance and mechanical properties of the performance changes of the difference. The results show that the shielding performance of B4C/Bi/NR and Gd2O3/Bi/NR against neutron 252Cf fission neutrons (slowed down by 12 cm thick polyethylene) increases gradually with the increase of B4C and Gd2O3 fillings, while the shielding rate of Gd2O3/Bi/NR against neutrons tends to be stabilized when the Gd2O3 content is higher than 40 phr. The experimental results are mutually verified with MCNP. It is found that the transmission ratios of 252Cf fission neutrons within the composite homogeneous materials all satisfy the exponentially decreasing law, and the composites have the best shielding ability for 252Cf fission neutrons when the B4C and Gd2O3 fillings are 80 phr, and the neutron reaction cross sections of B4C/Bi/NR and Gd2O3/Bi/NR are 0.265 cm−1 and 0.267 cm−1, respectively. In addition, the shielding performance of B4C/Bi/NR against 59.5 keV gamma rays decreases with the increase of B4C addition, whereas the shielding performance of Gd2O3/Bi/NR against 59.5 keV gamma rays is enhanced with the increase of Gd2O3 content. The mechanical properties of the natural rubber decrease with the addition of B4C, whereas the addition of appropriate amount of Gd2O3 (20 phr) helps to enhance the natural rubber’s. Gd2O3/Bi/NR composites have good neutron/gamma shielding properties and mechanical properties, which have potential applications as hybrid radiation field shielding materials.
SHU Nengchuan1, LIU Lile1, LIU Chao1, YANG Yi1, WANG Xiufeng2, QIAO Chunyuan3, LI Zeyu1, CHEN Yongjing1, GE Zhigang1, LIU Shilong1, , RUAN Xichao1, , CHEN Dongfeng1
Fission yield is one of the crucial data for nuclear power application and nuclear devices development, and plays an important role in the fundamental research such as nuclear fission physics research, element synthesis in nuclear astrophysics, and the mechanisms of superheavy nucleus synthesis. In this paper, the progress of nuclear fission yield research made by China Institute of Atomic Energy was mainly introduced. First, a series of fission yields measurements were introduced, including: the cumulative yields measurements of important fission systems using direct γ-ray spectrometry, especially the high-precision measurement of fission yields related to burnup; the cumulative yields measurements of low-yield nuclides from 235U fission induced by neutrons, and those of short-lived products from 252Cf spontaneous fission, as well as the mass chain yields and yield-energy relationships of important fission systems using the radiochemical method; measurements of mass distribution of primary fission products from 252Cf spontaneous fission and thermal neutron-induced fission of 235U and 2395Pu based on the kinetic energy-velocity (E-v) method and the established fission fragment identification spectrometer (FFIS). In addition, the innovative work carried out using the microscopic theory of fission was introduced. Within the framework of covariant density functional theory, the two-center harmonic oscillator basis and Fourier parameterization improve the theoretical calculation of the large deformation region close to the scission point, laying a solid foundation for the research on microscopic methods of nuclear fission. Within the framework of the macroscopic-microscopic model, the Langevin method coupled with neutron evaporation model has been developed, in order to consistently describe the fission dynamics and de-excitation process of fission fragments, and the prompt fission quantities including the independent fission yields, and the multiplicities and energy spectra of prompt neutron in 235U fission induced by neutrons are well reproduced using this method. Moreover, the progress of fission yield evaluation and database establishment was introduced, including fission yield evaluation methods based on machine learning, the 5-Gaussian model and the Zp model, as well as the evaluation of experimental data. Finally, the future development and prospects of fission yield research were presented. In terms of experimental measurement, efforts will be made to continuously improve measurement technologies, achieving high-precision measurements of yield-energy relationship data and independent yields. In the research on fission theories, models will be further improved to gradually realize the accurate description of various types of fission data. In addition, experimental data evaluation technologies and fission phenomenological models will be improved, and the evaluation of yields and yield-energy relationships for a series of important fission product nuclei will be completed.
Analysis of thermal transport in nanolubricants is an interesting and potential topic. Hence, the current research focuses on the study of ZnO-SAE50 by adding the major effects of variable thermal conductivity, combined convection, and thermal radiations. The physical set up is designed for 3D dimensional flow through a surface and then investigated the results via numerical scheme. From detailed analysis of the physical results, it is examined that ZnO concentration and suction effects cause reduction in the fluid movement while for stretching case these variations are quite rapid than shrinking case. Further, the combined convective effects greatly influenced the fluid motion over the surface. The velocity G′(η) increases rapidly under increasing Grashof effects and maximum motion is observed for stretching case. The temperature of ZnO-SAE50 enhanced due to increasing thermal radiations and ZnO concentration. However, minimal changes are investigated under variable thermal conductivity number ϵ, shterching/shrinking λ and maximum drop in the temperature is examined due to stronger Grashof number effects.
Medical physics. Medical radiology. Nuclear medicine, Nuclear engineering. Atomic power
Ivan M. Russkikh, Evgeniy N. Seleznev, Alexandra A. Zyryanova
et al.
When solving several research problems, the need arises for reactor testing of non-standard objects. The IVV-2M reactor is a pool, heterogeneous, light-water reactor. The 500 mm-high reactor core comprises six sections of six fuel assemblies (FA) with central water traps and a water trap in the center of the core. The personnel of INM JSC were tasked with testing an object whose length exceeded the height of the IVV-2M reactor core. A non-standard core layout was developed with six sections of seven fuel assemblies to accomplish this task.. The test object is located in the center of the core, surrounded by special aluminum blocks. Several fuel assemblies are installed on special supports, which allow the fuel assemblies to be installed 200 mm higher. Shim rods have been moved to the center of the sections. The safety of the developed arrangement was confirmed by neutron-physical calculations using the certified MCU-PTR software tool. Calculations have shown that the maximum maximum power in the fuel assembly is 236 kW, which is 50% less than the permissible value. To confirm the safety of the layout and ensure the required test conditions, tests of a mock-up of the object were carried out. The efficiency of the control members was experimentally determined. The overall efficiency of the control members was 4.85% ∆k/k, the physical weight of the object was 1.46% ∆k/k. Based on the requirements of the Nuclear Safety Rules for Research Reactors, the test duration is no more than three days. The distribution of neutron flux density over the height of the core was determined using indium neutron activation detectors. The developed design solutions made it possible to form a unique IVV-2M reactor core layout for testing objects exceeding its height.. Neutron-physical calculations and tests of the irradiated device mock-up confirmed the safety and performance of this core arrangement.
Hiroyuki Arakawa, Toshioh Fujibuchi, Kosuke Kaneko
et al.
Training for radiation protection and control requires a visual understanding of radiation, which cannot be perceived by the human senses. Trainees must also master the effective use of measuring instruments. Traditionally, such training has exposed trainees to radiation sources. Here, we present a novel e-training strategy that enables safe, exposure-free handling of a radiation measuring tool called a survey meter. Our mixed reality radiation-training system merges the physical world with a digital one. Collaborating with a mixed reality headset (HoloLens 2), this system constructs a mock-up of a survey meter in real-world space. The HoloLens 2 employs a browser-based application to visualize radiation and to simulate/share the use of the survey meter, including its physical movements. To provide a dynamic learning experience, the system adjusts the survey-meter mock-up readings according to the operator's movements, distance from the radiation source, the response time of survey meter, and shielding levels. Through this approach, we expect that trainees will acquire practical skills in interpreting survey-meter readings and gain a visual understanding of radiation in real-world situations.
In this paper we discuss the growing need for system behaviour to be validated and verified (V&V'ed) early in model-based systems engineering. Several aspects push companies towards integration of techniques, methods, and processes that promote specific and general V&V activities earlier to support more effective decision-making. As a result, there are incentives to introduce new technologies to remain competitive with the recently drastic changes in system complexity and heterogeneity. Performing V&V early on in development is a means of reducing risk for later error detection while moving key activities earlier in a process. We present a summary of the literature on early V&V and position existing challenges regarding potential solutions and future investigations. In particular, we reason that the software engineering community can act as a source for inspiration as many emerging technologies in the software domain are showing promise in the wider systems domain, and there already exist well formed methods for early V&V of software behaviour in the software modelling community. We conclude the paper with a road-map for future research and development for both researchers and practitioners to further develop the concepts discussed in the paper.
Oleksandr Kosenkov, Michael Unterkalmsteiner, Jannik Fischbach
et al.
Context: Regulatory acts are a challenging source when eliciting, interpreting, and analyzing requirements. Requirements engineers often need to involve legal experts who, however, may often not be available. This raises the need for approaches to regulatory Requirements Engineering (RE) covering and integrating both legal and engineering perspectives. Problem: Regulatory RE approaches need to capture and reflect both the elementary concepts and relationships from a legal perspective and their seamless transition to concepts used to specify software requirements. No existing approach considers explicating and managing legal domain knowledge and engineering-legal coordination. Method: We conducted focus group sessions with legal researchers to identify the core challenges to establishing a regulatory RE approach. Based on our findings, we developed a candidate solution and conducted a first conceptual validation to assess its feasibility. Results: We introduce the first version of our Artifact Model for Regulatory Requirements Engineering (AM4RRE) and its conceptual foundation. It provides a blueprint for applying legal (modelling) concepts and well-established RE concepts. Our initial results suggest that artifact-centric RE can be applied to managing legal domain knowledge and engineering-legal coordination. Conclusions: The focus groups that served as a basis for building our model and the results from the expert validation both strengthen our confidence that we already provide a valuable basis for systematically integrating legal concepts into RE. This overcomes contemporary challenges to regulatory RE and serves as a basis for exposure to critical discussions in the community before continuing with the development of tool-supported extensions and large-scale empirical evaluations in practice.
Ghareeb Moustafa, Ali M. El-Rifaie, Idris H. Smaili
et al.
This paper proposes a new Enhanced Dwarf Mongoose Optimization Algorithm (EDMOA) with an alpha-directed Learning Strategy (LS) for dealing with different mathematical benchmarking functions and engineering challenges. The DMOA’s core concept is inspired by the dwarf mongoose’s foraging behavior. The suggested algorithm employs three DM social categories: the alpha group, babysitters, and scouts. The family forages as a team, with the alpha female initiating foraging and determining the foraging course, distance traversed, and sleeping mounds. An enhanced LS is included in the novel proposed algorithm to improve the searching capabilities, and its updating process is partially guided by the updated alpha. In this paper, the proposed EDMOA and DMOA were tested on seven unimodal and six multimodal benchmarking tasks. Additionally, the proposed EDMOA was compared against the traditional DMOA for the CEC 2017 single-objective optimization benchmarks. Moreover, their application validity was conducted for an important engineering optimization problem regarding optimal dispatch of combined power and heat. For all applications, the proposed EDMOA and DMOA were compared to several recent and well-known algorithms. The simulation results show that the suggested DMOA outperforms not only the regular DMOA but also numerous other recent strategies in terms of effectiveness and efficacy.
El Saeed R. Lasheen, Hamdy A. Awad, Antoaneta Ene
et al.
Several commercial granitic rocks are widely used as decorative material (ornamental stones) due to their durability and fantastic colors. The present study aims to identify the mineralogical constituents as well as natural radioactivity of seven granitic rocks known as Gandonna, Pink Granite, Fantazia, Buff granites I, Buff granites II, Qusseir brown, red granites in order to deduce their suitability for different applications (decorative stone). Accordingly, in the petrographic investigation, the examined rocks comprise different proportions of essential minerals (potash feldspar, quartz, and albite) with some secondary minerals such as kaolinite and chlorite minerals. 238U, 226Ra, 232Th and 40K activity concentrations were detected by using NaI (Tl) scintillation γ-ray technique. Fantasia (av. 4.13 ± 5.85, 10.77 ± 1.9 Bqkg−1), and Gandonna (av. 12.4 ± 10.12, 35.01 ± 3.81 Bqkg−1) samples have the lowest mean 238U, and 232Th activities value, relative to other rock samples, which are lower than the recommended levels of UNSCEAR. Except for absorbed dose rate, numerous radiological indices such as outdoor and indoor annual effective dose, radium equivalent activity, external and internal indices, excess lifetime cancer risk and organs of effective dose are calculated for the examined stations to deduce the radiation effects on human organs. The obtained results reveal that the natural gamma radiation from these rocks is within acceptable limits.
Medical physics. Medical radiology. Nuclear medicine, Nuclear engineering. Atomic power
During the neutron detection process, owing to the effects of inelastic scattering and slow neutron capture, a neutron-gamma mixed radiation field is formed, which increases the complexity of neutron detection. Organic scintillators are widely used in neutron detection because of their high flashing efficiency, short decay time, and high detection efficiency. Pulse shape discrimination (PSD) is a key technology for discriminating neutrons and gamma rays according to the difference in pulse shape caused by the difference in particle decay time in organic scintillators. Traditional PSD methods include time-domain and frequency-domain discrimination methods. In recent years, various machine-learning techniques applied to neutron-gamma discrimination have achieved better results. To better use organic scintillators and the corresponding neutron-gamma discrimination methods in neutron detection, we conducted a comprehensive analysis of the glowing mechanism of organic scintillators, PSD principle, organic scintillator types, and neutron-gamma discrimination methods and investigated the performance evaluation indexes of organic scintillators and neutron-gamma discrimination methods. Finally, the future development directions of organic scintillators and neutron-gamma discrimination methods were examined.
The nuclear recoil effect, known also as the mass shift, is one of theoretical contributions to the energy levels in muonic atoms. Accurate theoretical predictions are therefore needed for extracting e.g. the nuclear charge radii from experimental spectra. We report rigorous QED calculations of the nuclear recoil correction in muonic atoms, carried out to all orders in the nuclear binding strength parameter $Zα$ (where $Z$ is the nuclear charge number and $α$ is the fine structure constant). The calculations show differences with the previous approximate treatment of this effect, most pronounced for the lowest-lying bound states. The calculated recoil correction was found to be sensitive to the nuclear charge radius, which needs to be accounted for when extracting nuclear parameters from the measured spectra.
Abstract In order to solve the digital transformation problems faced by Jiangsu Nuclear Power Station (TNPS) under the complex situation, and to benchmark advanced enterprises to improve the current digitalization level, TNPS established a special organization to carry out the V-type system construction method which covers user needs, functional requirements, architecture design, detailed design, code implementation, unit testing, integration testing, system testing, acceptance testing, etc. TNPS is carrying out the top-level design and application implementation of intelligent station, support platform and network construction and existing information systems based on the foundation functional and digital transformation, smart application and decision-making platform construction as the main body of the smart power plant implementation plan, and combed the application scenarios from the four dimensions of “personnel, equipment, environment, and operation”, and introduced smart nuclear power using smart construction sites and smart outage as examples Implementation content and solutions for typical applications. This work has advanced design and complete system, which has certain reference significance for nuclear power enterprises to carry out digital and intelligent transformation.
In the spectral mean cross section measurements of 197Au(n,2n)196Au and 45Sc(n,2n)44Scm, the activation products 196Au and 44Scm have low activity and shorter halflife, but the activation products 198Au and 46Sc from neutron capture reactions of 197Au(n,g) and 45Sc(n,g) have strong activity and longer halflife, which results in poor signaltonoise ratio of gammaray characteristic peaks, and increases the measuring uncertainty of 196Au and 44Scm activity. In order to accurately measure 196Au and 44Scm, a radioactive activity measuring device based on anticoincidence principle was developed. The main techniques used were as follows: Firstly, liquid flash measurement system has been used to detect the betaray emitted by the decay of 198Au and 46Sc, basing on the anticoincidence principle, the betaray would be used to suppress Compton background caused by gammarays emitted by the two nuclides above; Secondly, a portable antiCompton spectrometer has been constructed using a ring sodium iodide crystal, and the Compton background caused by the decay of 198Au and 46Sc has been further suppressed by the anti-Compton principle. Thirdly, a thin layer of lead shield has been placed between the radioactive source distributed evenly in the liquid scintillation and a wellshaped high purity germanium (HPGe) crystal to absorb the Xrays emitted by the decay of the 196Au, as results, the coincidence between the Xrays and the characteristic gammarays emitted by 196Au in the HPGe crystal reduces significantly, and the detection efficiency of this measurement device for 196Au increases too. By using the digital spectrometer, the liquid flash measurement system and the antiCompton spectrometer integrated into one, the anticoincidence effect could be superimposed and good experimental results were obtained. For 198Au and 46Sc, the anticoincidence inhibition ratio is 871% and 869% respectively. The detection efficiency for 44Scm is 313%. After increasing the shielding layer, the detection efficiency for 196Au increases greatly, from 5.5% when the shielding layer is not available up to 11.9%. Under the condition of strong isotope interference (198Au or 46Sc of 02 MBq), the minimum detectable activity (MDA) of 24 h detecting to 196Au is less than 07 Bq, and to 44Scm is less than 03 Bq. Applying the double anticoincidence measuring device established in this paper to the activity measurement of 196Au and 44Scm could effectively reduce the uncertainty of 197Au(n,2n)196Au and 45Sc(n,2n)44Scm average crosssection measurement.
The existence of a Coal-Fired Power Plant (CFPP) is suspected to affect the environment quality, especially the increment of natural radionuclides content which is found in coal as raw material.Therefore, systematic analysis of natural radionuclides (210Pb, 234Th, 238U, 228RA, 40K, 226RA and232Th) in water, soil, and plantwere conducted to establish a database of environmental contamination in the area around a CFPP. This research was conducted in the area around Adipala Cilacap CFPP which operates with two towers. Samples were taken from three locations around the Adipala CFPP based on the secondary wind direction data from Indonesian Agency for Meteorological, Climatological, and Geophysics in the 2018 dry season. Samples were prepared in the Radiochemistry Laboratory, Center for Accelerator Science and Technology, BATAN.The concentration of radioactivity in environmental samples were analyzed using gamma spectrometry with a high purity germanium detector for 24hours after reaching its secular equilibrium. The result of samples analysesshown that the mean value of the radionuclides specific activities (210Pb, 234Th, 238U, 228RA, 40K, 226RA and232Th) for water, cassava leaves, grass, and soil were 0.789 Bq/L, 14.685 Bg/kg, 15.036 Bq/Kg, and 75.083 Bq/kg, respectively. The mean of radium equivalent activity (Raeq)for water, cassava leaves, grass, and soil were 1.692, 30.792, 18.699 and 137.513 Bq/kg, respectively. The absorbed dose rate (ADR)for water, cassava leaves, grass, and soil were0.775, 14.332, 8.627, and 64.135 nGy/h, respectively, whilst the annual effective dose rate (AEDR) were 0.004, 0.070, 0.042, and 0.315 mSv/y. The mean of external and internal hazard indices(Hex and Hin) for water, cassava leaves, grass, and soil were 0.005 and 0.006, 0.083 and 0.129, 0.050 and 0.078, and 0.371 and 0.554, respectively, while the mean of excess lifetime cancer risk (ELCR)wre 0.014×10-6, 0.246×10-6, 0.148×10-6, and 1.101×10-6. According to the calculation of radiation hazard index in this research, it was understood that all parameters of all samples were within acceptable limits by the world average value reported by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR).
The coolant temperature feedback coefficient is an important parameter of reactor core power control system. To study the coolant temperature feedback coefficient influence on the core power control system of small PWR, the core power control system is built with the nonlinear model and fuzzy control theory. Then, the uncertainty quantification method of reactor core parameters is established based on the Latin hypercube sampling method and the Bootstrap method. Finally, under the conditions of reactivity step perturbation and coolant inlet temperature step perturbation, uncertainty analysis for two cases is carried out. The result shows that with fuzzy controller and fuzzy PID controller, the uncertainty of the coolant temperature feedback coefficient affects the core power control system, and the maximum uncertainties of core relative power, coolant temperature deviation, fuel temperature deviation and total reactivity are acceptable.
The binding energy (BE) or mass is one of the most fundamental properties of an atomic nucleus. Precise binding energies are vital inputs for many nuclear physics and nuclear astrophysics studies. However, due to the complexity of atomic nuclei and of the non-perturbative strong interaction, up to now, no conventional physical model can describe nuclear binding energies with a precision below 0.1 MeV, the accuracy needed by nuclear astrophysical studies. In this work, artificial neural networks (ANNs), the so called ``universal approximators", are used to calculate nuclear binding energies. We show that the ANN can describe all the nuclei in AME2020 with a root-mean-square deviation (RMSD) around 0.2 MeV, which is better than the best macroscopic-microscopic models, such as FRDM and WS4. The success of the ANN is mainly due to the proper and essential input features we identify, which contain the most relevant physical information, i.e., shell, paring, and isospin-asymmetry effects. We show that the well-trained ANN has excellent extrapolation ability and can predict binding energies for those nuclei so far inaccessible experimentally. In particular, we highlight the important role played by ``feature engineering'' for physical systems where data are relatively scarce, such as nuclear binding energies.
This dissertation deals with theoretical descriptions of nuclear fission and synthesis of superheavy elements via fusion. The associated shape evolutions are treated using a random-walk approach where both the potential energy and the nuclear level density influence the dynamics. The work in this thesis extends the random-walk model by, in addition to the previous description of fragment mass yields, also simulating how much kinetic energy the fission-fragments obtain and the number of neutrons they emit, as well as how these two quantities are correlated. The thesis also presents studies of how different ways of fissioning, called fission modes, are present in different nuclei and how the presence of these modes depends on the energy of the system. The model is furthermore applied to the description of the shape evolution in fusion for production of superheavy elements.
In most countries, the thermal criteria for the engineered barrier system (EBS) is set to below 100 °C due to the possible illitization in the buffer, which will likely be detrimental to the performance and safety of the repository. On the other hand, if the thermal criteria for the EBS increases, the disposal density and the cost-effectiveness for the high-level radioactive wastes will dramatically increase. Thus, fundamentals on the thermal behavior of the buffer under the elevated temperatures is of crucial importance. Yet, the behaviors at the elevated temperatures of the bentonite under groundwater-saturated conditions have not been reported to-date. Here, we have developed an in-situ synchrotron-based method for the thermal behavior study of the buffer under the elevated temperatures (25–250 °C), investigated d-spacings of the montmorillonite in the Korean bentonite (i.e., Ca-type) at dry and KURT (KAERI Underground Research Tunnel) groundwater-saturated conditions (KJ-ii-dry and KJ-ii-wet), and compared the behaviors with that of MX-80 (i.e., Na-type, MX-80-wet). The hydration states analyzed show tri-, bi-, and mono-hydrated at 25, 120, and 250 °C, respectively for KJ-ii-wet, whereas tri-, mono-, and de-hydrated at 25, 150, and 250 °C, respectively for MX-80-wet. The Korean bentonite starts losing the interlayered water at lower temperatures; however, holds them better at higher temperatures as compared with MX-80.