BIOCHEMICAL ENGINEERING JOURNAL
·
2013
·
IF 2.579
Zhongjie Wu,Wei Qi,Mengfan Wang,Yuefei Wang,Rongxin Su,Zhimin He
The ceramic powder with high metal content (MCP) was prepared as a new kind of immobilization carrier. Cu-MCP showed the best affinity to α-amylase and exhibited maximal activity. The effects of metal content, chelation time and amylase concentration on Cu-MCP-amylase activity were investigated. Under the optimal preparation conditions (the ratio of metal hydroxide precipitation to matrix (P/M): 0.23, chelation time: 8 h and amylase solution: 2.2 g/L), the activity of Cu-MCP-amylase could reach 31.5 U/g (54.5% of activity yield). Then, both Cu-MCP and Cu-MCP-amylase were characterized by XRD, SEM, BET-N 2 and FTIR. These characterizations confirmed that the Cu-MCP was a superior carrier with significant mechanical strength, considerable surface area, stable environment, homogeneous surface and low cost. Meanwhile, it also indicated that amylase had been efficiently immobilized on the external surface of Cu-MCP. Next, the properties of Cu-MCP-amylase were determined. It had optimal pH 7.0 and optimal temperature 70 °C with improved thermal stability. Finally, Cu-MCP-amylase showed significant catalytic capacity and stability in a column reactor, which could retain 80% of initial catalytic capacity after 40 recycle times.
研究领域:
生物化学
·
酶工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Pengchao Si,Chunyang Duan,Mengqi Li,Zenghua Zhao,Dong Zhao,Yunfa Chen,Yu Wang
Two-dimensional materials have been extensively investigated in the fields of electrochemical sensors, field-effect transistors, and other electronic devices due to their large surface areas, high compatibility with device integration, and so on. Conventional electrodes, such as precious metal layers that are deposited on polymer or silicon wafers, have gradually revealed increasing difficulties in adapting to various device structures, especially for two-dimensional materials, which prefer high exposure of surface atoms. Here, we demonstrate a tailorable metal–ceramic (Cu-TiC0.5) layered structure as novel electrodes with high mechanical property and conductivity and fabricate a highly sensitive gas sensor with graphene lying on this proposed electrodes. The Cu-TiC0.5 layered structure exhibits remarkably high tensile yield strength and compressive yield strength, which increase 7 and 8 times than those of the pure copper, respectively. Meanwhile, excellent flexibility and conductivity could also be obtained with the further thinning of the Cu-TiC0.5 layered composite, which shows its potential applications in flexible electronics. Finally, we demonstrated that a graphene-based gas sensor fabricated on tailored metal–ceramic electrodes was ultrasensitive and robust, which benefits from the good thermal conductivity and peculiar gas channels etched on the surface of copper alloy electrodes.
研究领域:
材料科学
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电子工程
✓ 已验证
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2024
·Vol. 34
·期 16
·2313645
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IF 18.5
Yongshi Guo,Xiaohua Zhang,Feng Jiang,Xuwang Tian,Jiawei Wu,Jianhua Yan
Cermet has broad applications in electronics, but achieving stable ceramic-metal contact has always been a challenge, particularly at hot temperature and large deformation conditions, due to the significant differences in thermal expansion coefficient and stiffness of ceramics and metals. Here, stress matching and strong interphase bonding at the heterogenous ceramic-metal contact are realized by using flexible ceramics, leading to stable applications in flexible fire-resistant pressure tactile sensors. Cu/Au nanolayers are deposited first onto the toughened flexible SiO 2 nanofibers with a chemical plating method to form sensitive interdigital electrode sensors, then use an in situ thermal reaction strategy to form conformal and interlocked Au 3 Cu and CuSiO 3 interphases, which enhance the mechanical thermal stability of the ceramic-metal contact. With deep learning technique, the as-fabricated intelligent pressure tactile gloves can accurately recognize the human body parts in low-visible burning environments and show a long-term stability over 1000 cycles with a high sensitivity of 112.18 kPa −1 , which is important for developing intelligent firefighting.
研究领域:
材料科学
·
传感器技术
·
智能设备
✓ 已验证
DOI
高影响因子
Additive Manufacturing
·
2024
·
IF 10.3
Ming-Yue Jiang,Xiang-Yu Meng,Jin Zhou,Zhen-Yu Wei,Hai-Feng Zhang,Ping Shen
Optimizing the composition and structure of materials in localized regions of the materials is an effective approach to enhance the material utilization efficiency and achieve a performance-on-demand design. However, it is challenging to achieve such design owing to limitations in manufacturing technology . In this study, we devised a method involving vat photopolymerization 3D printing and magnet-assisted pressure infiltration techniques for fabricating near-net-shape customized gradient composites with Al/Al 2 O 3 as the model system. The mechanical properties of the fabricated Al/Al 2 O 3 composites at specific locations could be optimized by appropriately setting the thickness ratio of the metal layer to the ceramic layer , and a desirable combination of strength , toughness, and wear resistance could thereby be achieved. The fracture behavior of the composites was analyzed through in situ observation and finite element simulations . The proposed design concept and fabrication method are flexible and adaptable, and they can be easily extended to other material systems and structural models. They are expected to pave the way for the development of lightweight, strong, tough, and near-net-shape structural and functional materials .
研究领域:
材料科学
·
制造工程
✓ 已验证
产品关联
DOI
高影响因子
Friction
·
2023
·Vol. 11
·期 5
·801-819
·
IF 6.8
Liu Chenxu,Tian Yu,Khan Zulfiqar A.,Meng Yonggang
Corrosion and corrosive wear occur commonly on metals surface in aqueous solutions. External electric field is usually considered as one of the factors to accelerate corrosion or corrosive wear of materials in the presence of conventional electrolytes. This work aims to reposition widely believed perspective by experimental justification which have been conducted in aqueous solutions containing surfactants. Electric potential of metal surfaces was modulated externally within the electrochemical potential window of the metal electrode-solution-counter electrode system, which actively regulated the adsorption or desorption of surfactant molecule in the aqueous solution over the electrodes to form a molecular barrier of electron transportation across the electrode-electrolyte interface. The advantage of the approach over the anodic passivation is negligible redox reactions on the protected electrode surface while a better lubricious and wear resistant film than oxide is maintained in the meantime. Tribopairs of several metal/metal and metal/ceramic were tested by employing a ball-on-disc tribometer with anionic and cationic surfactants solutions. For anionic surfactant as the modifier, positive surface potential enables coefficient of friction to be decreased by promoting the formation of adsorption film on metal surface in aqueous solutions. For cationic surfactant, negative surface potential plays a role in decreasing the coefficient of friction. Phase diagrams of friction and wear in wide ranges of surfactant concentration and surface potential were plotted for the tested metal/metal and metal/ceramic tribopairs. These results indicate that the adsorption behavior of molecules or ions at the metal-aqueous interface can be well regulated when an external electric field is present without inducing corrosion or corrosive wear.
研究领域:
材料科学
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电化学
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表面化学
·
摩擦学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Wei Zhang,Fusheng Yin,Zhenhui Cheng,Suping Peng,Chunwen Sun
To achieve the commercial application of solid oxide fuel cells (SOFCs), the performance degradation of the cell caused by carbon deposition needs to be well addressed. Here we report a new anode with nanostructured heterogeneous interfaces by integrating 0.38 wt% Sn and 0.19 wt% MgO into Ni SDC for hydrocarbon-fueled SOFCs. The cell with 0.38Sn–0.19MgO Ni SDC anode exhibits a peak power density of 374 mW cm −2 and excellent long-term stability for 100 h with a power attenuation about 13.5% in humidified methane at 700 °C, which is attributed to the decreased rate of carbon deposition by promoting the formation of C O bonds instead of C C bonds, increasing the activation barrier for methane cracking and preventing the formation of nickel carbides by the confinement effect of heterogeneous catalysts, and the enhanced rate of carbon removal is attributed to excellent hydrophilicity and adsorption of CO 2 , as revealed by combined density function theory (DFT) calculations and experimental characterizations. This finding offers potential for the application of hydrocarbon-fueled SOFCs and provides a guide for designing coking-tolerant anodes.
研究领域:
材料科学
·
能源工程
·
化学工程
·
电化学
✓ 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）