CERAMICS INTERNATIONAL
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2018
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IF 3.057
Ping Hu,Yuan Cheng,Maosong Xie,Yu Yang,Chang Liu,Qiang Qu,Xinghong Zhang,Shanyi Du
The damage mechanism of carbon fiber and fiber-ceramic interface of C f /ZrC-SiC were investigated and revealed. The chemical reactions of C with ZrO 2 and SiO 2 impurities during the sintering resulted in the surface and grain etching of fiber. The ZrC-SiC ceramics diffused into interface to form a strong bonding under high temperature and press, leading to a failure of stress release and guiding the crack propagation direct across fiber. Both consequently impeded the fiber pull-out and bridging. By obvious contrast, the chemical etching of fiber was effectively inhibited utilizing PyC coating as transition layer, and the strong bonding of fiber with ceramic was relieved at the same time replaced by a relatively weak bonding. As a result, the fiber pull-out and fiber bridging were boosted with a longer length more than 50 µm, over 2 times of uncoated composite, accompanied with obvious crack branching and deflection, together resulting in a graceful mechanical feedback with 2.5 times of work of fracture and improved fracture toughness . This work not only revealed the microstructure forms and inherent mechanism on structure damage of carbon fiber, but also offered an effective method of protecting fiber and tailoring the interface bonding, thereby guiding the design of C f /ZrC-SiC with graceful mechanical performance.
研究领域:
材料科学
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复合材料
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界面工程
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
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IF 7.312
Linfeng Miao,Xiaolin Wu,Zhongli Ji,Zhen Zhao,Cheng Chang,Zhen Liu,Feng Chen
Different drying conditions and three types of porous fibrous ceramics with different contents and dispersions of the silica-based binder were used to prepare catalytic filter elements (CFEs) for the simultaneous removal of NO x and dust, and their effects on the catalytic performances were also investigated. The results indicated that the content and dispersion of the silica-based binder had a significant effect on the catalytic activity of the CFE. The removal of useless binder in the pores and the inhibition of binder agglomeration could improve the NO conversion. Compared with traditional electric heating blast drying, microwave drying effectively inhibited the migration of titanium sol so that the catalyst in the prepared CFE had good uniformity and dispersion. Meanwhile, microwave drying changed the morphology, crystal grain, and pore structure of the catalyst support (TiO 2 ), ultimately increasing the specific surface area. Furthermore, this study also determined that the optimal average output power for microwave drying was 385 W. With a filtration velocity of 1 m/min, NO and NH 3 inlet concentrations of 600 ppm, and an O 2 content of 5 vol%, the prepared CFE achieved more than 98% NO conversion in the temperature range of 250 to 350 °C, and its highest conversion of 100% was achieved at 275–325 °C.
研究领域:
材料科学
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环境工程
✓ 已验证
DOI
高影响因子
Arabian Journal of Chemistry
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2020
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IF 4.762
Yusuf Olabode Raji,Mohd Hafiz Dzarfan Othman,Nik Abdul Hadi Sapiaa Md Nordin,Zhong ShengTai,Jamilu Usman,Stanley Chinedu Mamah,Ahmad Fauzi Ismail,Mukhlis A. Rahman,Juhana Jaafar
In this study, low-cost magnesium bentonite (MB) was used for the fabrication of bentonite hollow fibre (BHF) membrane with high pure water flux. MB powder was initially characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), particle size distribution (PSD) analyser, Brunnauer -Emmett- Teller (BET) method, and field emission scanning electron microscope (FESEM). The BHF membrane obtained was then fabricated through dope suspension mixing, phase inversion and sintering process. The dope suspension was prepared by mixing MB, dispersant, polymer binder, and solvent using a planetary ball mill. While the spinning process was carried out at the extrusion rate of 8 mL/min, a fluid bore rate of 10 mL/min and air gap of 5 cm, and this was followed by sintering operation at 950 °C, 1000 °C, 1050 °C, and 1100 °C. The resulting BHF membrane was characterized by scanning electron microscopy (SEM) and XRD; the porosity test, water flux and oil rejection were also examined. The SEM surface morphology of BHF at sintering temperature of 950 °C showed spongy-like and nested macrovoids structure; the porosity was 49.09% with a mean pore size of 3.9 µm. The performance test on the bentonite-based hollow fibre membrane showed that the membrane prepared at 20 wt% and sintering temperature of 1000 °C, which induced high and stable permeate water flux and oil rejection of BHFC membrane were 544 L/m 2 h and 97%, respectively. The results have shown that the presence of magnesium in bentonite can enhance and promote the needed support material for the fabrication of hollow fibre ceramic membrane.
研究领域:
材料科学
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环境工程
✓ 已验证
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2023
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IF 5.7
Chaochao Cao,Jingwen Yang,Shaobo Yang,Wenjuan Bai,Dong Wang,Song Yan,Yanming Xue,Xiongwei Qu,Chengchun Tang
Hexagonal boron nitride ( h -BN) materials with excellent physicochemical stability and processibility have been considered as promising engineering materials . However, their practical applications are rather limited by the difficulty in constructing the well-bonded h -BN ceramic. Herein, we present a reaction welding strategy for facile preparation of well-bonded h -BN fibers (BNFs) network by using ethanolamine (ETA) containing alcoholic hydroxyl and primary amine groups as crosslinking agent. The formed >B-O-H 2 C-H 2 C-H 2 N|→B< bond bridges through the esterification and intramolecular coordination (N|→B) reactions between ETA molecules and BNFs containing surface hydroxyls, play an essential role in the construction of the thermodynamically stable >B-N-B< covalent bond between BNFs. Based on this synthetic strategy and a room-temperature molding process followed by a calcination step, a series of resilient BNFs ceramics with high processibility, typical diamagnetism, low dielectric constant (∼ 2.1) and loss, good resistance to temperature different, corrosion, oxidation and abrasion are produced. Besides, they also exhibit excellent strain and damage tolerance, the maximum compression strain and strength can reach up to 38% and ∼ 33 MPa, respectively. Significantly, the deliberately designed BNFs vessel can be successfully used for the alloying of high melting point metals, showing both structural/chemical robustness and good reusability. This ingenious design for well-bonded BNFs network not only is a good model for exploring the welding way for h -BN powders, but also opens up numerous opportunities for practical applications.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2023
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IF 5.2
Linfeng Miao,Zhongli Ji,Xuetao Wang,Xiaolin Wu
The fibrous ceramic-based catalytic filter element (CFE) is a promising multifunctional material capable of simultaneously removing dust and NO x from hot gases. In this study, various calcination temperatures and titanium sols with different solid contents were used to prepare CFEs based on microwave drying, and their influences on the catalytic performance were experimentally investigated. The results showed that both the calcination temperature and the solid content of the titanium sol had important impacts on the catalytic activity. As the calcination temperature increased, the particle size, crystallite size , and average pore diameter of the loaded catalyst support (TiO 2 ) increased, while the specific surface area decreased, ultimately resulting in a decline in the catalytic activity. However, a suitable calcination temperature ranging from 300 to 400 °C was required to achieve a good combination between the catalyst and the fibrous ceramic and a relatively uniform mesoporous structure. Furthermore, the increase in the solid content gave rise to a corresponding increase in the TiO 2 loading amount, which increased the pressure drop and reaction surface area of the CFE. Excessive vanadium content caused by insufficient catalyst support induced side reactions of NH 3 oxidation under high-temperature conditions, thereby reducing catalytic activity. Therefore, the preferred calcination temperature and solid content were set at approximately 300–400 °C and 8 wt%, respectively. The final prepared CFE demonstrated superior catalytic performance and adaptable gas velocity properties.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）