Article
Materials Science, Ceramics
Wei Zhang, Qingsong Ma, Kuanhong Zeng, Weiguo Mao
Summary: The study found that C/Mullite composites annealed in an inert atmosphere exhibited better thermal stability compared to those annealed under a vacuum, with carbothermal reduction being the main factor for failure. The activation temperature of carbothermal reduction in the inert atmosphere was approximately 100 degrees C higher than in the vacuum, leading to irreversible degradation of mechanical properties once activated and destruction of the microstructure.
CERAMICS INTERNATIONAL
(2022)
Review
Engineering, Environmental
Yajuan Ma, Shuaijun Wang, Xiaoguang Duan
Summary: Photocatalytic carbon dioxide (CO2) reduction is a promising strategy for mitigating global warming and providing green fuels and chemicals. However, current photocatalysts have low adsorption capacity and limited CO2 dissolution, resulting in unsatisfactory conversion rates and selectivity in aqueous solutions. This paper reviews the latest advances in metal-organic frameworks (MOFs) and polymer-based photocatalysts for gas-solid CO2 conversion. Porous photocatalysts exhibit high efficiency in photocatalysis due to favorable CO2 adsorption and selectivity, even at ultralow CO2 concentrations or in the presence of oxygen. Challenges and future perspectives for developing multifunctional materials with high CO2 adsorption and photocatalytic conversion performances are also discussed.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Environmental Sciences
Bo Cao, Jianhua Qu, Yingyu Chu, Yujiao Zhu, Yuxin Jiang, Xiubo Zhang, Mingze Sun, Zhao Jiang, Shouyi Ma, Ying Zhang
Summary: Nanoscale zerovalent iron (nZVI) encapsulated in a carbon matrix shell was synthesized to inhibit oxidation and agglomeration. The core-shell structure provided diversified active sites, allowing for efficient phenol degradation in a wide pH range and in the presence of coexisting substances. The nZVI(0.6)-BC800/PS system exhibited over 85% removal of phenol after multiple recycles or prolonged storage, making it a promising catalyst for water treatment.
Article
Chemistry, Multidisciplinary
Xiaodong Wu, Na Yang, Yuanxiao Ji, Xuexia He, Qi Li, Ruibin Jiang, Zhibin Lei, Zonghuai Liu, Jie Sun
Summary: This research investigates the phase transformation from TiO2 to TinO2n-1 and characterizes the phase composition and interface structures of the products at different temperatures using transmission electron microscopy. The crystallographic features of the observed interfaces have been calculated based on modified invariant line theory, confirming the consistency of the experimental observation and calculated results.
Article
Materials Science, Multidisciplinary
He Zhang, Na Wang, Jing Li, Yu-Qing Wang, Peng-Fa Feng, Yu-Fei Zuo, Guo-Hua Zhang, Kuo-Chih Chou
Summary: Ultrafine Mo (W) powders were obtained through a two-stage reduction process, including carbo-thermal pre-reduction of MoO3 (WO3) and deep hydrogen reduction. The increase in reaction time reduced the residual carbon contents of pre-reduced products without significantly affecting the particle sizes. After deep hydrogen reduction, the residual carbon contents of the obtained powders were further reduced.
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
(2023)
Article
Engineering, Environmental
Shakeel Ahmad, Feilong Gao, Honghong Lyu, Jingkang Ma, Beibei Zhao, Siyu Xu, Cholnam Ri, Jingchun Tang
Summary: This study investigates the removal of hexavalent chromium and nitrobenzene using iron and nitrogen doped biochar composites. The results show that the Fe1-N1-BC1 composite exhibits higher efficiency and stability in pollutant removal, and is capable of simultaneously removing different types of pollutants.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Materials Science, Ceramics
Ying Long, Guihao Zhang, Shiming Lin, Hua-Tay Lin
Summary: This study investigated the phase composition, microstructure, and mechanical properties of WB2-B4C composites fabricated through a combination of boro/carbothermal reduction and spark plasma sintering (SPS) method. The experimental results showed that after SPS sintering at 1600 degrees C under an applied load of 30 MPa for 10 min, the relative density of the as-sintered composites reached around 93.1% and 99.5%. The SEM analysis revealed a network structure with WB2 grains surrounded by B4C grains, while HRTEM analysis showed a semi-coherent interface and lattice distortion transition region between WB2 and B4C grains. The Vickers hardness, fracture toughness, and flexural strength of the WB2-B4C composites were significantly improved due to the fully dense, solid solution of C, and the semi-coherent interface between WB2 and B4C grains.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Nanoscience & Nanotechnology
Wiktoria Lipinska, Katarzyna Grochowska, Jacek Ryl, Jakub Karczewski, Katarzyna Siuzdak
Summary: The study investigated the annealing process of AuCu layers on TiO2 nanotubes in different atmospheres and found that thermal treatment in argon atmosphere resulted in the highest photoactivity. The presence of spherical nano-particles on the external and internal walls of the nanotubes was confirmed through scanning electron microscopy images. Overall, thermal processing led to changes in optical, structural, electrochemical, and photoelectrochemical activities of the materials.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Physical
Zhuqi Wang, Shenghui Deng, Qiyun Zhang, Jingze Li, Qilang Lin
Summary: The surface-modified carbon foams developed through carbothermal reduction exhibit a porous and rough surface with embedded iron oxide particles, showing excellent electrochemical and mechanical properties. The specific capacitance at 1 A g(-1) can reach a high value, reflecting the potential of these foams as electrode materials.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Physical
Gang Sun, Ying Yang, Zhiwei Yao, Yan Shi, Wei Mao
Summary: The CR method for synthesizing MoP catalysts with different surface carbon contents and particle sizes was studied in this work for dry reforming of methane. The study found that surface carbon content and particle size are key factors influencing the oxidation resistance ability (ORA) and methane dissociation ability (MDA) of MoP, while specific surface area has no effect. MoP-Glu with appropriate surface carbon content and particle size showed higher catalytic stability in DRM compared to MoP-HMT and MoP-PFR.
CATALYSIS SCIENCE & TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
Youngho Jee, Hae Jun Ahn, Sun Jie Kim, Se-Hee Lee, Kyeong-Wung Kim, Chang Min Kim, Seung Hun Huh
Summary: The differences between carbothermal reduction and graphenothermal reduction of metal oxide and graphite or graphene systems have not been thoroughly investigated. In this study, the relationship between crystalline growth and chemical reduction during the heat-treatment of reduced graphene oxide (RGO) and NiO nanoparticles was investigated. The heat-treated RGO/NiO mixtures showed complex interactions, where below a critical NiO concentration, the crystalline growth of RGO and NiO took precedence, and above this threshold, drastic Ni formation occurred by the chemical reduction of NiO. This study highlights the concentration-dependent competitive relationship between chemical reduction and crystalline growth, and emphasizes the need for further investigation into the shape/contact-dependent chemical reactivity between RGO and NiO, as well as the thermodynamic size-dependent driving force for crystalline growth of individual RGO and NiO crystals.
Article
Green & Sustainable Science & Technology
N. F. M. Yunos, M. A. Idris, N. A. Nasrun, A. Kurniawan, T. Nomura, S. A. Rezan
Summary: This research focuses on investigating the effects of different carbon reductants on the properties and phase transition of ilmenite ore. The results show that palm char has a better reduction effect than graphite, achieving a TiO2 reduction degree of 81.8% at the highest reduction temperature. In the early and middle stages of high-temperature reactions, solid carbon and CO participate in the carbothermal reduction of ilmenite ore, producing rutile, iron, and Ti3O5. In the later stages, rutile, iron, and Ti2O3 are mainly formed during the hydrogen reduction process.
JOURNAL OF SUSTAINABLE METALLURGY
(2023)
Article
Engineering, Chemical
Tlek Ketegenov, Kaster Kamunur, Aisulu Batkal, Rashid Nadirov
Summary: This study investigates the synthesis of barium sulfide using carbothermal reduction in compacted mixtures. The results demonstrate that compaction enhances the conversion of barium sulfate to sulfide and reduces the activation energy.
Article
Chemistry, Physical
Qi Qin, Jing Chen, Meng Song, Fengyi Cao, Yunan Li, Fang He, Zhongzhu Liu, Genxing Zhu, Quan Diao
Summary: In this study, silicon carbide nanowires were successfully prepared by microwave sintering using graphene and ethyl orthosilicate as precursors. The samples were fully characterized and analyzed by XRD, FTIR, and SEM. The results demonstrated that microwave sintering is a more energy-efficient, cost-saving, and efficient way to synthesize SiC.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Ceramics
Xu Hao, Shiqin Wan, Songmo Du, Zhanglin Chen, Jie Zhang, Xuanyi Yuan, Qi Wang
Summary: In this study, red-emitting spherical AlN:Mn2+ phosphors were successfully prepared using a nitrogen pressure-assisted carbothermal reduction-nitridation method. The optimum preparation parameters were explored and it was found that uniform spherical shape, large particle size, low impurity content, and appropriate Mn2+ concentrations could significantly enhance the luminous intensity of the phosphors. The structural compositions were characterized and it was confirmed that Mn2+ ions were successfully doped into the AlN lattice, providing the red-emitting luminescence centers. The underlying growth mechanism of the spherical AlN phosphors was proposed, emphasizing the importance of proper amount of liquid Ca-aluminates for achieving uniform morphology and high fluorescence efficiency.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2022)
Article
Energy & Fuels
Yan Peng, Jishan Liu, Guangqing Zhang, Zhejun Pan, Zhixiao Ma, Yibo Wang, Yanan Hou
Summary: This study focuses on the prediction of rock permeability and introduces a geometry-based permeability model. By considering stress concentration and displacement of pore surfaces, this novel approach outperforms conventional models as it explicitly incorporates the effects of pore geometry and stress orientation on permeability.
JOURNAL OF NATURAL GAS SCIENCE AND ENGINEERING
(2021)
Article
Thermodynamics
Sai Meng, Paul Zulli, Chaohe Yang, Zhe Wang, Qingbo Meng, Guangqing Zhang
Summary: This article introduces a novel concept for an intensified gasification process and compares it with conventional fluidised bed gasification process to demonstrate potential improvements in energy and exergy efficiencies. The intensified gasification process can increase energy and exergy efficiencies compared to the conventional process within a certain temperature range.
Article
Energy & Fuels
Yuanxun Nie, Bisheng Wu, Guangqing Zhang, Li Zhang, Zhengda Lei, Shaoyi Cheng, Haitao Zhang, Shiyuan Li
Summary: This study investigates the CO2-brine-rock interactions and their effects on the microstructure of sandstone. The results show that confining pressure reduces the degree of damage in different scales and alters the pore system. The study also reveals that CO2-brine saturation increases porosity and decreases the fractal dimension of the sandstone.
Review
Energy & Fuels
Jianlin Zhao, Junjian Wang, Guangqing Zhang, Dawei Zhou, Li Chen, Hari Viswanathan, Qinjun Kang
Summary: Shale gas reservoirs are an important unconventional resource with unique characteristics. The ultrasmall pore sizes in shale induce the nanopore confinement effect and gas adsorption. The lattice Boltzmann method (LBM) has been modified to simulate gas flow and adsorption in shale rocks, and four types of LBM models have been developed for this purpose. LBM can efficiently estimate shale gas permeability, describe pore-scale flow behaviors, and address the influence of gas adsorption, but challenges remain in its application for shale gas flow and adsorption simulations.
Article
Energy & Fuels
Yanan Hou, Yan Peng, Yishan Liu, Zhangxin Chen, Baitao Fan, Zhiming Yin, Guangqing Zhang
Summary: This study compares the influence of constant amplitude, constant mean stress (CACMS) cyclic loading and constant amplitude, increasing mean stress (CAIMS) cyclic loading on the strength and fatigue lifetime of shale using a series of uniaxial compression tests. A fatigue lifetime model for CAIMS is established and a nonlinear damage accumulation model is proposed to predict damage evolution. It is found that the CAIMS cyclic loading significantly decreases the strength and fatigue lifetime of shale, making it a less efficient loading type compared to CACMS.
Article
Engineering, Geological
Lei Chen, Guangqing Zhang, Min Zhang, Chaohao Zhai, Zongyang Fan, Jianlin Zhao, Dawei Zhou, Shiyuan Li
Summary: In this paper, the slip nucleation during fracture propagation in laminated shale formations during hydraulic fracturing was studied using macro and micro three-point bending experiments, as well as visual hydraulic fracturing experiments. The digital image correlation method (DIC) was used to monitor the interlaminar deformation and a method to identify the slip nucleation zone (SNZ) using DIC was proposed. The findings of this study could enhance understanding of the generation mechanism of slips in shale reservoirs during hydraulic fracturing.
ROCK MECHANICS AND ROCK ENGINEERING
(2023)
Article
Chemistry, Physical
Di Pan, Guangqing Zhang, Fanghui Jia, Lianjie Li, Tao Zhang, Yao Lu, Hui Wu, Ming Yang, Zhengyi Jiang
Summary: In this paper, the effects of glycerol-based lubricant containing TiO2 NPs on micro deep drawing (MDD) of austenitic stainless steel (ASS) SUS301 were studied. The use of TiO2 nanolubricants significantly improved the quality of the drawn cups in terms of decreased wrinkling and surface roughness. The concentration of TiO2 NPs influenced lubricity by reducing friction during the MDD process, and the optimal concentration was found to be 2 wt%. The lubrication mechanisms were derived from the mending effects of TiO2 NPs and the formation of thin lubricant films associated with open and close lubricant pockets theory.
Article
Engineering, Mechanical
Wenrui Wang, Guangqing Zhang, Hu Cao, Lei Chen, Chunyang Zhao
Summary: Alternate fracturing is a more effective method for increasing natural gas production, as it can form complex fracture networks and control fracture geometry more efficiently. The critical factors affecting the generation of branch fractures are the fracture spacing and the number of main fractures.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Engineering, Mechanical
Di Pan, Guangqing Zhang, Hui Wu, Fanghui Jia, Lianjie Li, Tao Zhang, Ming Yang, Zhengyi Jiang
Summary: In this study, micro deep drawing experiments were conducted on an austenitic stainless steel using lubricants containing different mass fractions of graphene nanosheets (GNS) in ethanol. The friction-reduction mechanisms of the GNS in the micro deep drawing process were discussed by analyzing the profile and surface roughness of the microcups. The results showed that GNS could reduce friction and improve surface quality, with the lubricant containing 10 mg/ml GNS achieving the best results in terms of drawing force, wrinkling, and surface roughness.
Article
Engineering, Chemical
Di Pan, Guangqing Zhang, Fanghui Jia, Yao Lu, Jun Wang, Zhou Li, Lianjie Li, Ming Yang, Zhengyi Jiang
Summary: This study examines the influence of TiO2 nanolubricants and graphene lubricants on micro deep drawing (MDD). The research findings show that using a 5.0 mg/mL graphene lubricant together with TiO2 nanolubricants can significantly reduce drawing force and improve the consistency of the produced microcups.
Article
Energy & Fuels
Xuelin Zheng, Guangqing Zhang, Lei Chen, Min Zhang, Renyi Qiu, Dawei Zhou, Jianlin Zhao
Summary: Hydraulic fracturing is crucial for shale oil and gas production, and using liquid nitrogen (LN2) as a fracturing agent shows promise. This study combines laboratory experiments and numerical simulations to analyze the cryogenic fracturing mechanisms of LN2 in shale. The experiments use digital image correlation to record the fracturing processes and observe three typical modes of induced fractures in shale with beddings. A numerical model is developed to simulate the thermal-mechanical coupling and analyze the applicability of different fracture criteria. The findings provide references for shale fracturing treatments with LN2.
GEOENERGY SCIENCE AND ENGINEERING
(2023)
Review
Energy & Fuels
Jianlin Zhao, Junjian Wang, Guangqing Zhang, Dawei Zhou, Li Chen, Hari Viswanathan, Qinjun Kang
Summary: This review examines four lattice Boltzmann models developed for simulating shale gas flow/adsorption and discusses the current challenges in applying these models.
Article
Materials Science, Multidisciplinary
Huaixuan Feng, Xue-feng She, Xiao-min You, Guang-qing Zhang, Jing-song Wang, Qing-guo Xue
Summary: This work investigated the extraction of iron and removal of sodium from red mud using the technology of carbothermic reduction. The effects of various parameters on melting separation and de-alkalization were studied. Optimal conditions for metallization rate and sodium removal were achieved at a reduction temperature of 1,450 degrees C, basicity of 1.5, and reduction time of 12 min. The microstructure of the pellets revealed increased aggregation of iron particles at a basicity of 1.5. X-ray diffraction analysis indicated that the final phase composition of the reduced pellets is mainly Ca2Al2SiO7, which has applications in cement materials and glass ceramics.
HIGH TEMPERATURE MATERIALS AND PROCESSES
(2022)
Article
Mining & Mineral Processing
Huibin Li, D. J. Pinson, P. Zulli, L. Lu, R. J. Longbottom, S. J. Chew, B. J. Monaghan, G. Zhang
Summary: Channel iron deposits (CID) are a significant iron ore resource in Western Australia, and this study compared the complex mineral phases in CID goethitic ore with traditional hematite ore. The changes of goethitic ore when heated to different temperatures were investigated, revealing temperature-induced phase transformations and colour changes.
MINERAL PROCESSING AND EXTRACTIVE METALLURGY-TRANSACTIONS OF THE INSTITUTIONS OF MINING AND METALLURGY
(2022)
Article
Materials Science, Multidisciplinary
Huibin Li, David J. Pinson, Paul Zulli, Liming Lu, Raymond J. Longbottom, Sheng J. Chew, Brian J. Monaghan, Guangqing Zhang
Summary: The study investigated the interaction between mineral phases in two commercial iron ores and flux materials, finding that CaO was the most effective flux for liquid phase generation during sintering. The presence of goethite in one of the ores facilitated the assimilation of hematite/martite phases. MgO diffused into hematite ore grains by solid-state diffusion and formed a solid solution without the formation of a liquid phase.
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
(2021)
