Article
Thermodynamics
Rongkun Pan, Cong Li, Jiangkun Chao, Daimin Hu, Hailin Jia
Summary: With the increased depth of coal energy mining in China, the occurrence of coal spontaneous combustion has become more frequent, posing a serious threat to the safe mining of coal energy. Investigating the process of coal oxidation and spontaneous combustion by examining its thermal and microstructural properties is crucial for understanding the mechanism of coal spontaneous combustion. Experimental results show that the thermal properties of coal spontaneous combustion exhibit obvious segmentation characteristics that are independent of metamorphism degree and heating rates, and the initial exothermic temperature is positively correlated with heating rates. The effect of temperature on microscopic characteristics is uneven, but the metamorphism degree shows regular changes in microscopic characteristics. Thermal dynamic balance is an important factor in microstructure changes.
Article
Environmental Sciences
Houssam Slimanou, Amina Baziz, Nedjima Bouzidi, Dolores Eliche Quesada, Abdelkader Tahakourt
Summary: This study demonstrates that utilizing dredged sediments as raw materials in ceramic tile production can substitute kaolin and improve the physical properties of ceramic products. From mineralogical analysis and leaching evaluation results, it is shown that dredged sediment and calcined sediment can effectively immobilize heavy metals, producing environmentally friendly ceramic building materials.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Jiawen Feng, Wanyuan Gui, Qian Liu, Wenya Bi, Xuechong Ren, Yongfeng Liang, Junpin Lin, Benli Luan
Summary: In this study, the electron beam selective melting (EBM) technique was used to shape Ti-48Al-2Cr-2Nb alloy, resulting in high-density samples. The mechanism of phase transformation and microstructural evolution as well as the interaction with tensile properties were investigated. The EBM-formed Ti-48Al-2Cr-2Nb alloy exhibited a unique microstructure and superior mechanical properties.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Energy & Fuels
Zhidong Tang, Zhenya Zhou, Jianping Jin, Yongsheng Sun, Yuexin Han, Yahui Zhang
Summary: This study presents a two-stage roasting technology to enhance the leaching efficiency of vanadium. The effects of roasting factors on vanadium leaching rate and the mechanism of extracting vanadium from stone coal were investigated. XRD analysis was used to analyze the phase transformation of minerals during roasting, while SEM, EDS, and BET analysis were used to study microstructure changes. The results showed that the two-stage roasting technology achieved a vanadium leaching recovery of 80.26% under optimal conditions. This study confirms that the two-stage roasting technology is a more environmentally friendly and effective method for extracting vanadium from stone coal.
Article
Materials Science, Ceramics
Yeqing Ling, Xiandong Hao, Yuxi Gui, Hongju Qiu, Qiannan Li, Hewen Zheng, Mamdouh Omran, Lei Gao, Jin Chen, Guo Chen
Summary: Nanosized CeO2-ZrO2 powders prepared by atmospheric pressure pyrolysis were used as raw materials to prepare CeO2-ZrO2 ceramics using microwave sintering. When the CeO2 content is more than 5 mol%, the tetragonal phase peak appears in the sample, and the grain size of the ceramics is negatively related to Ce content. CeO2 reduces the solid solution's phase transformation temperature with microwave heating.
CERAMICS INTERNATIONAL
(2021)
Article
Materials Science, Multidisciplinary
Nachiket Keskar, K. V. Mani Krishna, Chiradeep Gupta, J. B. Singh, R. Tewari
Summary: The development of microstructure, texture, and mechanical properties in single and two-phase recrystallized and aged Ni-Cr binary alloys were investigated. The recrystallization of γ-Ni phase was influenced by the deformation texture and the concurrent precipitation of α-Cr phase in the two-phase alloys. The α-Cr precipitation resulted in the hardening of the aged two-phase alloys. The deformation texture after aging could be correlated to the change in stacking fault energy due to Cr content. The dominance of certain recrystallization textures could be explained by the advantage of "oriented growth" offered by the concurrent α-Cr precipitation on grain boundaries.
MATERIALS TODAY COMMUNICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Xin Wang, Guanjun Zhu, Jia Liu, Amei Zhang, Hongping Hou, Y. P. Zhang, Hongliang Du
Summary: The microstructural stability and mechanical properties of a novel Al1.2CrCuFeNi2 dual-phase high entropy alloy were studied. The alloy exhibited a uniform near-eutectic structure composed of Ni-Al rich B2 matrix and Cr-Fe rich BCC spherical phases with an average grain size of about 100 nm. After annealing at 1000 degrees C, the alloy experienced precipitation of ultrafine particles and transformation from spherical to needle-like structure. The as-cast and annealed alloys demonstrated impressive combinations of yield strength, fracture strength, and plastic strain, and the hardness was also significantly improved after annealing, indicating excellent tempering softening resistance of the alloy.
Article
Materials Science, Ceramics
Binghuan Gao, Seongwan Jang, Hyeonjin Son, Sujin Park, Hee-Soo Lee, Chang-Jun Bae
Summary: The correlation between phase transformation, microstructure evolution, and flexural strength of geopolymer composites was investigated. It was found that a Si:Al ratio of 1.94 and curing time of 24 hours maximize the sodalite content, resulting in a dense microstructure and high flexural strength. However, increasing the Si:Al ratio to 2.22 reduces flexural strength due to the impeditive effect of excessive silica on geopolymerization and the transformation of sodalite to cancrinite.
CERAMICS INTERNATIONAL
(2022)
Article
Construction & Building Technology
Shukai Cheng, Keyu Ge, Tao Sun, Zhonghe Shui, Xuyong Chen, Jian-Xin Lu
Summary: This study found that thermally activated coal-series kaolin, combined with mechanical grinding, demonstrated good pozzolanic reactivity in cement paste and mortar, significantly accelerating the early hydration of cement paste. The thermoactivated kaolin contributed to refining the pore structure and improving the compressive strength of blended mortar, showing potential as an alternative supplementary cementitious material.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Chemistry, Physical
Jiaquan Li, Zhiwei Huang, Qian Wang, Fengnian Zhang, Yang Miao, Feng Gao
Summary: In this study, aluminium fluoride trihydrate (AlF3 center dot 3H(2)O) was used to inhibit the sintering of calcined coal-series kaolin (CCSK) and to improve its oil absorption properties. The effects of calcination temperature and the addition of AlF3 center dot 3H(2)O on the particle-size distribution, specific surface area, and porosity of CCSK were investigated. Scanning electron microscopy, X-ray diffraction, and thermogravimetric analysis were used to study the morphology, structure, phase composition, and phase transition of the specimens. It was found that the addition of 10 wt.% AlF3 center dot 3H(2)O had the best sintering inhibition effect on CCSK at 1000 degrees C. The release of SiF4 gas and the formation of submicron mullite whiskers caused by AlF3 center dot 3H(2)O moderated the formation of molten-phase liquid bridges between particles and inhibited sintering. The formation of submicron mullite whiskers on the surface of CCSK particles significantly enhanced their oil-absorption properties.
Article
Materials Science, Ceramics
Chao Wu, Shihui Xie, Mengyong Sun, Xiaobo Liu, Huaguan Li, Sang Xiong, Xu Zhang
Summary: In this study, amorphous nanocarbon particles were added to prepare nanocarbon-reinforced TiB2-SiC-B4C composite ceramics. The phase transformation and microstructural evolution induced by the nanocarbon particles were analyzed. Furthermore, the mechanical properties of the composites were significantly improved due to the optimized fracture mode and reinforcement of the nanocarbon particles.
CERAMICS INTERNATIONAL
(2022)
Article
Chemistry, Physical
Md Mofizur Rahman Mollah, Biswajit Samanta, Soumen Das, Pabitra Ghosh, Ashish Jain, Kitheri Joseph
Summary: Zr-rich U-xZr (x = 40.5, 52 & 75 wt%) alloys were prepared by arc melting technique to improve homogeneity and microstructural attributes. The solidus-liquidus temperatures, phase transformation, and crystallographic growth were studied using spot technique, differential scanning calorimetry (DSC), X-ray diffraction (XRD), and field emission scanning electron microscopy (FESEM). The results showed different solidus-liquidus temperatures for each Zr content, and the presence of different phases depending on the Zr content. The composition analysis revealed low uncertainties in determining the U and Zr composition.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Jingfeng He, Xin Zhang, Qiang Bai, Shibo Huang, Hao Chen, Chengjing Guo, Lingtao Zhu, Bin Yang
Summary: This research aimed to enhance the decarbonization performance of coal-series kaolin by surface modification through triboelectric separation. The results showed that the adsorption of citric acid or kerosene improved the charging performance of kaolinite and coal. Moreover, citric acid exhibited a more significant improvement compared to kerosene. The triboelectric separation efficiency of coal-series kaolin was enhanced after surface modification, with citric acid achieving more effective separation.
APPLIED CLAY SCIENCE
(2023)
Article
Construction & Building Technology
Qiang Ma, Yubiao Li, Yang Li, Yuanyuan Liu, Shaomin Lei
Summary: This study investigated the hydration process of blended mortars and their resistance to seawater degradation in the presence of calcined coal-series kaolin (CCK). The results showed that CCK has high pozzolanic activity and can promote the hydration reactions in mortars, resulting in improved strengths and reduced seawater degradation. This study provides a new strategy for preparing high-strength mortars with high resistance to seawater degradation.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Automation & Control Systems
Alima Mebrek
Summary: This research investigated the influence of sintering temperature on microstructural and physical properties of refractory bricks, finding significant changes in phase composition and transformations at different sintering temperatures. The presence of cordierite and other substances in sintered pellets were closely related to sintering temperature, while density decreased with increasing sintering temperature.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2021)
Article
Chemistry, Physical
Nadine J. Kanik, Artur Kuligiewicz, Jeffrey T. Cullen
Summary: This study examined the effects of different pre-treatments on the structural H-isotope composition of clay minerals. The results showed that different pre-treatments had varied impacts on different clay minerals, and the choice of pre-treatment should be based on the specific properties and mineralogy of the samples.
APPLIED CLAY SCIENCE
(2024)
Article
Chemistry, Physical
Lorenzo Lisuzzo, Giuseppe Cavallaro, Stefana Milioto, Giuseppe Lazzara
Summary: This study proposes Pickering emulsions based on wax and halloysite clay nanotubes for coating silk sutures to increase their loading capacity towards eosin. The presence of halloysite/wax microspheres on the surface of silk sutures has also been explored for controlled release of hydrophobic drugs. The influence of the coating on the thermal and mechanical properties of the sutures has been studied using various techniques. In conclusion, the wax/halloysite Pickering emulsions can successfully generate hydrophobic microdomains on the surface of silk sutures, leading to enhanced flexibility and improved loading capacity towards eosin.
APPLIED CLAY SCIENCE
(2024)
Article
Chemistry, Physical
Bruna F. Alves, Rita C. P. Nunes, Luiz C. Bertolino, Elizabete F. Lucas
Summary: Operational problems in the oil industry caused by the precipitation of paraffins can be prevented by using polymeric additives. This article evaluates the use of polymeric nanocomposites as pour point reducers in different types of crude oil and finds that they are more efficient than pure poly(ethylene-covinyl acetate) (EVA) in reducing the pour point. The nanocomposites also modify the wax crystals and reduce the viscosity of the oil samples.
APPLIED CLAY SCIENCE
(2024)
Article
Chemistry, Physical
K. A. Daniels, C. C. Graham, A. C. Wiseall, J. F. Harrington, P. Sellin
Summary: Geological storage with clay buffer is widely preferred for removing hazardous radioactive waste. The impact of fluid salinity and void space on the swelling behavior of barrier bentonites was examined through experiments. The findings suggest that clay swelling is suppressed at higher salinities, which affects the void-filling process.
APPLIED CLAY SCIENCE
(2024)
Article
Chemistry, Physical
N. Werling, A. Kuligiewicz, A. Steudel, R. Schuhmann, F. Dehn, K. Emmerich
Summary: Thermal treatment of clay minerals can be used to produce building materials and environmentally friendly binders. This process involves dehydration, dehydroxylation, breakdown of structure, and recrystallization of high temperature phases. Rehydration and rehydroxylation are important factors to consider for geopolymers and SCM.
APPLIED CLAY SCIENCE
(2024)
Article
Chemistry, Physical
Xuan Wang, Hao Ding, Zhuoqun Xu, Jianmeng Zhang, Yanbin Yao
Summary: Rutile nano-TiO2 was loaded onto the surface of sericite to prepare sericite-rutile composite particles, which were then modified with HDTMS and sprayed onto the substrates to form sericite-rutile/HDTMS composite coatings with UV shielding and superhydrophobic self-cleaning properties. The coating exhibited good UV shielding rate and remained superhydrophobic after UV irradiation. The hierarchical structure of the sericite-rutile composite and the low surface energy of HDTMS contributed to the superhydrophobicity and UV shielding effect of the coating.
APPLIED CLAY SCIENCE
(2024)
Article
Chemistry, Physical
Kailang Sun, Taojun Zhang, Jie Zhou, Yonghong Liu, Minfeng Zeng, Zhen Yang, Ruokun Feng, Xiaorong Ren, Peng Zhang, Baoyi Wang, Xingzhong Cao
Summary: Chitosan-Pd0 nano particles encapsulated in Al, Co-pillared montmorillonite nanocomposites were successfully synthesized using a facile one-pot heat treatment method. The Al, Co pillaring effectively expanded the surface area and generated numerous mesopores in the interlayer space of the MMt. The resultant nanocomposite exhibited similar high comprehensive catalytic performances as the one prepared by the regular divided-multistep method. The encapsulation of CS chains and doping of Co in the Al pillaring also contributed to the improved catalytic performance.
APPLIED CLAY SCIENCE
(2024)
Article
Chemistry, Physical
Nathalie Fagel, Isabel Israde-Alcantara, Reza Safaierad, Marttiina Rantala, Sabine Schmidt, Gilles Lepoint, Pierre Pellenard, Nadine Mattielli, Sarah Metcalfe
Summary: Environmental conditions significantly influence clay minerals, and studying clay sediments in tropical lakes can provide valuable insights into past environmental conditions. In this study, multiproxy records from sediment cores of three crater lakes in central Mexico were analyzed. The results showed that disordered kaolinite, formed through hydrolysis and hydrothermal alteration, was the predominant mineral in the sediments. The abundance of kaolinite varied in relation to organic carbon and organic matter-related elements, and showed opposite trends with lithogenic elements. Geochemical data suggested that the increase in kaolinite abundance is linked to the formation of organo-mineral aggregates and lake level changes in closed basins.
APPLIED CLAY SCIENCE
(2024)
Article
Chemistry, Physical
M. J. Martin-Alfonso, A. Mejia, F. J. Martinez-Boza, P. Partal
Summary: The drilling industry is facing new challenges to develop eco-friendlier drilling fluids. Organic modified sepiolite dispersed in oil can be an excellent additive with suitable rheological properties. This study investigated the effect of alkyl ammonium modifiers on the microstructure and rheological properties of sepiolite-vegetable oil dispersions under high-temperature and high-pressure conditions.
APPLIED CLAY SCIENCE
(2024)
Article
Chemistry, Physical
Weiquan Zhan, Siyuan Yang, Shenxu Bao, Liuyi Ren, Cheng Liu
Summary: The interaction between talc and the depressor CMC was investigated through molecular dynamics simulation and density functional theory calculation. It was found that CMC showed stronger adsorption on the edge plane of talc due to enhanced interactions with polar groups and water molecules. The study also revealed specific interactions between H atoms in CMC and O atoms in the edge plane, as well as between O atoms in CMC and Si, Mg atoms in the edge plane. Hydration shells on the basal and edge planes of talc were examined to explain the phenomenon.
APPLIED CLAY SCIENCE
(2024)
Article
Chemistry, Physical
Pierre Dramou, Yiyang Sun, Xu Ni, Fangqi Wang, Hua He
Summary: In this study, a magnetic nanocomposite was prepared and used for the separation of rutin from real samples through magnetic solid phase extraction (MSPE). The nanocomposite exhibited high specific surface area, chemical and thermal stability, water solubility, and easy separation in aqueous solution. Characterization and experiments confirmed the successful synthesis and efficient enrichment ability of the nanocomposite.
APPLIED CLAY SCIENCE
(2024)