Materials
·
2023
·Vol. 16
·期 4
·1544
·
IF 3.4
Angxuan Wu,Yuchen Zhu,Chen Xu,Nianping Yan,Xuetong Zhao,Xilin Wang,Zhidong Jia
Arc floating in surface flashover can be controlled by reducing the interfacial charge-transfer resistance of ceramics. However, thus far, only a few studies have been conducted on methods of treating ceramic surfaces directly to reduce the interfacial charge-transfer resistance. Herein, we explore the flash sintering behavior of a ceramic surface (3 mol% yttria-stabilized zirconia (3YSZ)) onto which loose metal (iron) powder was spread prior to flash sintering at room temperature (25 °C). The iron powder acts as a conductive phase that accelerates the start of flash sintering while also doping the ceramic phase during the sintering process. Notably, the iron powder substantially reduces the transition time from the arc stage to the flash stage from 13.50 to 8.22 s. The surface temperature (~1600 °C) of the ceramic substrate is sufficiently high to melt the iron powder. The molten metal then reacts with the ceramic surface, causing iron ions to substitute Zr4+ions and promoting rapid densification. The YSZ grains in the metal-infiltrated area grow exceptionally fast. The results demonstrate that spreading metal powder onto a ceramic surface prior to flash sintering can enable the metal to enter the ceramic pores, which will be of significance in developing and enhancing ceramic–metal powder processing techniques.Keywords:flash sintering;room temperature;YSZ;metal powders;arc
研究领域:
材料科学
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陶瓷加工
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Chen Li,Wei Liu,Fen Jiao,Congren Yang,Gonghao Li,Shiyang Liu,Wenqing Qin
Electric arc furnace dust (EAFD), an important secondary resource, is categorized as hazardous solid waste which contains multiple heavy metals such as zinc, lead and chromium. Smelting-Reduction is considered as an effective method to recover metal elements from EAFD. To efficiently separate the zinc, lead, iron and slag from EAFD, a novel and clean process developed to enhance reduction and lower smelting temperature through sodium carbonate was proposed herein. Thermodynamic analysis and laboratory experiments were carried out to determine the feasibility and reliability of this new process. The optimal conditions were determined as temperature of 1450 °C, sodium carbonate dosage of 4%, C/O of 0.8, holding time of 30 min and basicity of 0.8, and the corresponding volatilization of Zn and Pb could be 99.78% and 89.47% respectively; besides, the reduction of iron could reach 98.98%. Simultaneously, the recovery of iron reached 98.62% and the grade of iron amounted to 93.8%. The melting reduction process of zinc, lead and iron could be divided into three stages according to both the experimental results and the thermodynamic analysis. The short process which is characteristic of high efficiency and low energy consumption, aims to provide a clean and sustainable approach to utilize EAFD.
研究领域:
冶金工程
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
RESOURCES CONSERVATION AND RECYCLING
·
2024
·
IF 11.2
Jingdong Huang,Xiao Yang
Natural Zn reserves may be exhausted in the coming decades. Electric arc furnace (EAF) dust is an essential secondary Zn resource. However, the traditional methods for separating Zn from EAF dust are plagued by high energy consumption, large carbon emissions, and severe environmental pollution, which hinder sustainable development. To address these challenges, a novel technology using molten MgCl 2 has been proposed. Under an air atmosphere at 1000°C, the chlorination percentage of Zn can exceed 97%. The ZnCl 2 content in the volatile products can reach up to 85 mass%, with minor impurities consisting mainly of PbCl 2 , KCl, and NaCl. Molten salt electrolysis experiments indicate that removing Pb 2+ and Fe 3+ ions and subsequently preparing metallic Zn is feasible. With its streamlined process, characterized by high efficiency and low energy consumption, this technology offers a clean and sustainable solution for metal recovery from EAF dust.
研究领域:
冶金工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Applied Sciences-Basel
·
2021
·Vol. 11
·期 19
·9127
·
IF 2.679
Tianji Liu,Yitong Wang,Junguo Li,Qing Yu,Xiaoman Wang,Di Gao,Fuping Wang,Shuang Cai,Yanan Zeng
The effects of Ca2+in converter slag and electric arc furnace slag leaching solutions on CO2content, the effects of CO2content in solutions on the accumulation of chlorophyll a ofNannochloropsissp., and the mechanisms were studied. Results showed that addition of 50 mg/L converter slag leaching solution and 400 mg/L electric arc furnace slag leaching solution (lower than 50 vol% concentration) promoted the accumulation of chlorophyll a ofNannochloropsissp., while an increased concentration of 70 vol% inhibited its accumulation. The highest concentration of chlorophyll a was obtained on the addition of 10 vol%. With 10 vol% leaching solutions added, chlorophyll a concentration for converter slag reached 4.2 mg/L, 1.45 times as much as that of pure F/2 medium, and chlorophyll a concentration for electric arc slag reached 3.2 mg/L, 1.10 times as much as that of pure F/2 medium. Under the same addition proportion, the promoting or inhibiting effect from converter slag on the accumulation of chlorophyll a ofNannochloropsissp. was more obvious than that for electric arc furnace slag. The reason for the promotion of chlorophyll a accumulation ofNannochloropsissp. was that an increase of Ca2+in the solutions led to an increase of CO2, thereby promoting the photosynthetic rate of microalgae. The study provided new ideas for the green application of solid waste and industrial production of microalgae.Keywords:leaching solutions;converter slag;electric arc furnace slag;Nannochloropsissp.;chlorophyll a;CO2content
研究领域:
环境科学
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微生物学
✓ 已验证
产品关联
DOI
高影响因子
Coatings
·
2023
·Vol. 13
·期 2
·252
·
IF 3.4
Yunzhang Li,Meng Zhou,Yi Zhang,Hanjing Zhu,Xianhua Zheng,Shengli Liang,Shunlong Tang,Baohong Tian,Yong Liu,Xu Li,Alex A. Volinsky,Chenglin Zheng
With the massive penetration of electronics into human life, higher demands are placed on electrical contacts. Among them, the lifetime of electrical contacts and safety are the most concerning. In this research, Al2O3-Cu/25Mo5Ta and 0.5Y2O3/Al2O3-Cu/25Mo5Ta composites were prepared by using ball milling and powder metallurgy methods. The two composites were subjected to 10,000 contact opening and closing electrical contact experiments and the arc duration and arc energy were analyzed. The results show that the addition of Y2O3has a slight effect on the mechanical properties of the Al2O3-Cu/25Mo5Ta composites but has a significant effect on the electrical contact performance. Y2O3can reduce the mass loss of the electrical contacts during the electrical contact process, which prolongs their service life. The addition of Y2O3decreased the average arc duration and arc energy of the electrical contact material by 21.53% and 18.02%, respectively, under the experimental conditions of DC 30 V, 10 A. TEM results showed that nanoscale YTaO4with excellent thermal stability was generated during the sintering process, which has a positive effect on the electrical contact performance of the composites.Keywords:copper matrix composites;electrical contact;arc erosion behavior;yttrium tantalate
研究领域:
材料科学
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电气工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Central South University
·
2021
·Vol. 28
·期 9
·2701-2710
·
IF 1.716
Zhang Du-chao,Liu Ruo-lin,Wang Hao,Liu Wei-feng,Yang Tian-zu,Chen Lin
To recover zinc from electric arc furnace (EAF) dust, a process of primary normal pressure leaching and secondary alkaline pressure leaching is proposed. First, under the alkaline pressure leaching system, the experiment of pure zinc ferrite being reduced by iron powder was carried out. Under the optimal reduction conditions (i.e., temperature of 260 °C, NaOH concentration of 6 mol/L, liquid-to-solid ratio of 50 mL/g, and a 5-fold excess of iron powder), 89% of zinc was extracted. The iron in the reduced residue exists as a magnetite phase. Subsequently, the normal pressure leaching experiment was carried out with EAF dust as raw material, and 66% zinc was leached. The main phase of zinc in normal leaching residue was determined to be zinc ferrite. Then, the normal leaching residue was reduced by iron powder under the alkaline pressure leaching system, and 66.5% of zinc was extracted. After the two-stage leaching process, the leaching rate of zinc in EAF dust can achieve 88.7%. The alkaline pressure leaching solution can be returned as the normal pressure leaching solution, and the magnetite in the alkaline pressure leaching residue can be recovered by magnetic separation.
研究领域:
冶金工程
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环境工程
✓ 已验证
DOI
高影响因子
Journal of Sustainable Metallurgy
·
2023
·Vol. 9
·期 3
·1253-1266
·
IF 2.4
Huang Jingdong,Li Guangqiang,Yang Xiao
Natural Zn reserves might be exhausted in the following decades. Electric arc furnace (EAF) dust is an essential secondary Zn resource. The recovery of Zn from EAF dust is a critical factor in the sustainable development of the Zn industry and steelmaking industry. Efficient destruction of the ZnFe 2 O 4 crystal structure and separation of Zn and Fe are the key issues to recycle EAF dust. Molten metal chlorides are believed to be effective in breaking the structure of ZnFe 2 O 4 . This work clarifies the distinct reaction behavior between ZnFe 2 O 4 and MgCl 2 or CaCl 2 . Experiments show that although MgCl 2 is a more powerful chlorinating agent, the capability of separating Zn and Fe is not as good as that of CaCl 2 . Fast and selective chlorination of Zn from ZnFe 2 O 4 happens by reacting ZnFe 2 O 4 and MgCl 2 –CaCl 2 mixture. CaCl 2 facilitates the formation of stable Fe-bearing phases, such as MgFe 2 O 4 and Ca 2 Fe 2 O 5 , thereby inhibiting the chlorination of Fe. Moreover, it becomes more effective in promoting the selectivity of chlorinating Zn by increasing temperature after adding CaCl 2 in MgCl 2 . When ZnFe 2 O 4 is subjected to chlorination using a MgCl 2 –CaCl 2 mixture (MgCl 2 –CaCl 2 –ZnFe 2 O 4 molar ratio = 1.5:1.5:1) at 950 °C for 120 min, the process results in a chlorination percentage of over 90% for Zn, with Fe chlorination percentage lower than 5%. These results demonstrate the prospect of efficient separation of Zn from ZnFe 2 O 4 by reaction with molten MgCl 2 –CaCl 2 mixture. Graphical Abstract
研究领域:
冶金工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THERMAL SPRAY TECHNOLOGY
·
2021
·Vol. 31
·期 1
·119-129
·
IF 2.757
Wen Jianxin,Song Ziheng,Chen Xiuyong,Li Hua
Biofouling has been persisting as a worldwide problem due to the difficulties in finding efficient environment-friendly antifouling coatings for long-term applications. Developing novel coatings with desired antifouling properties has been one of the research goals for surface coating community. Recently hydrogel coating was proposed to serve as antifouling layer, for it offers the advantages of the ease of incorporating green biocides, and resisting attachment of microorganisms by its soft surface. Yet poor adhesion of the hydrogel on steel surfaces is a big concern. In this study, porous matrix aluminum coatings were fabricated by cored wire arc spray, and the sizes of the pores in the aluminum (Al) coatings were controlled by altering the size of the cored powder of sodium chloride. Silicone hydrogel was further deposited on the porous coating. The hydrogel penetrated into the open pores of the porous Al coatings, and the porous Al structure significantly enhanced the adhesion of the hydrogel. In addition, hydrogel coating exhibited very encouraging antifouling properties.
研究领域:
材料科学
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表面工程
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
VACUUM
·
2024
·
IF 3.8
Guangfeng Zhou,Haijun Wu,Yayu Deng,Rui Miao,Deyong Lai,Jingui Deng,Jian Zhang,Qian Chen,Qingyi Shao,Cairu Shao
Carbon nanotubes (CNTs) are a significant candidate for future channel materials for high-performance electronic devices, and this has attracted the attention of many researchers. Due to the scattering of defects in carbon nanotubes, the migration of charge carriers is greatly reduced, and the synthesis of defect free carbon nanotubes is an urgent and important issue that needs to be addressed. In this study, high-purity graphite powder served as the carbon source, and iron served as the catalyst to synthesize defect free MWCNTs through direct-current arc discharge (AD) in a nitrogen atmosphere. The effects of different pressures and catalysts on the yield and morphology of CNTs were studied. As the nitrogen pressure inside the vacuum chamber increases, the MWCNTs become longer and more erect. Fe has a high defect repair efficiency, which promotes the synthesizing of lattice-perfect and defect-free MWCNTs. It is found that the MWCNTs mainly exist in the iron mesh near the cathode. Using iron as a catalyst, we synthesize very straight MWCNTs with clearer walls under nitrogen pressure of 60 kPa. The results show that the method is characterized by low cost, implementability, and the ability to synthesize high-quality, defect free MWCNT compared to the conventional AD method.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2024
·
IF 3.8
Yuanji Gao,Yijun Liu,Xingyu Li,Kaineng Huang
Herein, ambient electric arc ionization mass spectrometry was used to examine 16 plasticizers in various wrap films, demonstrating high sensitivity (detection limit: <0.2 ng/mg) and precision (intra-/inter-day precision: <12 %). The ease of operation helps in the identification of wrap film and plasticizer analysis. In addition, the introduction of a cold arc plasma treatment presents a practical and innovative method for effectively eliminating plasticizers. This innovative strategy has implications for both environmental protection and food safety.
研究领域:
环境科学
·
食品安全
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TRIBOLOGY INTERNATIONAL
·
2024
·
IF 6.1
Qiang Gao,Qingyao Li,Wenhao Chen,Wenpeng Wang,Zixiang Wu,Zhuopei Zhang,Yong Wan,Yange Feng,Daoai Wang
The wear of friction pairs, especially under current-carrying conditions, significantly reduces equipment performance and service life due to electric arc erosion. This study employs laser surface texturing on copper blocks to create microporous structures, with polyaniline grease synthesized in situ based on these microscale reactors to reduce material wear and arc erosion. Results demonstrate that this method effectively fills the microporous with grease, ensuring grease supply under starved lubrication and long-term stable operation of friction pairs. The textured sample with a diameter of 140 µm at 6 A exhibits a 74.3 % reduction in coefficient of friction, 2.7 times less wear, extremely low arc erosion, and an electrical contact resistance of only 2.5 mΩ, maintaining stable tribological performance even after 21,600 cycles.
研究领域:
材料科学
·
摩擦学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2024
·
IF 3.9
Wei Wei,Fengjian Chu,Guanru Chen,Shiwen Zhou,Cuirong Sun,Hongru Feng,Yuanjiang Pan
The abiotic synthesis of peptides, widely regarded as one of the key chemical reactions on the prebiotic Earth, is thermodynamically constrained in solution. Herein, a simulation of the lightning phenomenon on the sea surface using bubble bursting and arc plasma under ambient conditions enables dipeptide formation of six amino acids with conversion ratios ranging from 2.6% to 25.5%. Additionally, we observed the formation of biologically active tripeptides and investigated the stereoselectivity of the dipeptide formation reaction. By utilizing a mixture of 20 amino acids in the reaction, 102 possible dipeptides were generated. These results establish experimental constructions to mimic achievable prebiotic conditions and provide a credible pathway for endogenous biopolymer synthesis on prebiotic Earth.
研究领域:
前生物化学
·
生命起源
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）