CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2018
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IF 1.712
Na Zhou,Yan Du,Chunyu Wang,Rizhi Chen
The state-of-the-art approaches for adjusting the structural characteristics of porous carbons are the after-treatments, which are complicated and time consuming. In this work, a facile approach was developed, i.e. , controlling the initial oxygen concentration in-situ during the direct carbonization of zeolitic imidazole framework-8 (ZIF-8), to adjust the pore structure and prepare hierarchically porous carbons. The introduction of oxygen can significantly affect the crystalline and pore structures of porous carbons, and promote the pore widening and the formation of mesopores . An appropriate initial oxygen concentration can notably enhance the surface area and mesopore volume of porous carbon, and then improve the adsorption capacity toward methylene blue (MB) dye from water by 3.4 times. The developed approach is more efficient at lower carbonization temperature. Moreover, the introduction of oxygen can increase the ratio of HO C O groups on the carbon surface, leading to enhanced interaction with MB molecules and higher adsorption capacity toward MB. The as-prepared porous carbons exhibit superior adsorption capacities toward MB dye as compared to the reported ZIF-8 derived carbons. These findings would aid the development of porous carbon materials with high performance.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Microbiology
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2022
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IF 6.064
Huang Ming-Qing,Zhang Ming,Zhan Shu-Lin,Chen Lin,Xue Zhen-Lin
In situ fragmentation bioleaching is a promising way to perform deep mining safely, economically, and in an environmentally friendly manner, where oxygen plays a critical role in microbial growth and mineral dissolution. However, the lack of oxygen limits the implementation of in-situ fragmentation bioleaching. To overcome this limitation, aeration was proposed, with saturated dissolved oxygen concentration as an important indicator. Orthogonal experiments were conducted to measure saturated dissolved oxygen concentration at various temperature, pH, and electrolyte (ferrous sulfate, ferric sulfate, copper sulfate, and sulfuric acid) concentration conditions. Experimental data were analyzed by Python programming language and least squares method to obtain a saturated dissolved oxygen concentration model. Results showed that temperature had the most significant effect on oxygen solubility, which was concluded by comparing the results of surface fitting based on the least squares method. At 30–40°C, the saturated dissolved oxygen concentration decreased faster as metal ions concentration increased. The conjoint effect of the five variables on oxygen solubility showed that pH was linearly negatively related to oxygen solubility. Additionally, a mathematical model was also proposed to predict the saturated dissolved oxygen concentration in in situ fragmentation bioleaching of copper sulfide ores. This work enables bioleaching processes to be modeled and controlled more effectively.
研究领域:
微生物学
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采矿工程
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环境科学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
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2023
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IF 2.5
Fan Shenglong,Sun Fengyun,Huang Zubo,Hao Yingchao,Zhang Wanyu,Zhang Yujie,Yu Hongji,Liu Jian
Enzymatic biofuel cells are regarded as a promising method to meet the increasing demand for the power source. However, low output power is still a problem to be overcome in this field. Here, we constructed a glucose oxidase/horseradish peroxidase biofuel cell and for the first time systematically explored the role of oxygen solubility and mass transport in enhancing the power output of a biofuel cell combined with finite element analysis. It was confirmed that the increase of oxygen solubility led to higher electron transfer efficiency, which increased the maximum power density from 19.40 to 24.97 μW cm −2 . Additionally, the main results show that the relative distance and position of the electrodes affect the mass transport between the cathode and anode, which in turn affects the performance of the fuel cell. Under the computed oxygen solubility of 1.919 ± 0.20 mM and the optimal structure, the biofuel cell fabricated on the carbon paper exhibited an open circuit potential of 0.41 V and maximum power density of 27.41 μW cm −2 and remained 82.4% of its original maximum power density after 20 days. This paper provides a facile and effective route for developing the output of enzymatic biofuel cells by enhancing dissolved oxygen concentration and mass transfer that would be of great significance to the structural design of enzymatic biofuel cell devices.
研究领域:
生物化学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SUPERCRITICAL FLUIDS
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2022
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IF 4.514
Jianqiao Yang,Jiyuan Sun,Shuyuan Bai,Hao Wu,Shuzhong Wang,Yanhui Li,Wenhao Ma,Donghai Xu
To improve the corrosion resistance of component materials in supercritical water oxidation (SCWO) environment, a 15 µm Cr coating was prepared on Alloy 625 by magnetron sputtering, and the effect of oxygen concentration (0 M, 0.16 M, and 0.94 M) on the stability of the Cr coating in an SCW environment was investigated. Results show that the stability of the Cr 2 O 3 layer strongly depends on the oxygen concentration in the exposure environment. The protective Cr 2 O 3 layer was transformed to soluble Cr(VI) species and dissolved in SCW containing 0.94 M oxygen. Except for Cr 2 O 3 , some Fe/Ni containing oxides were also detected. The stability of the Cr coating in SCW with different concentrations of oxygen is discussed.
研究领域:
材料科学
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腐蚀与防护
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表面工程
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能源环境工程
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高温化学
✓ 已验证
DOI
高影响因子
Particuology
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2025
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IF 4.3
Xueqin Liao,Haiou Wang,Peihui Xu,Jianzhong Liu,Jianren Fan
Although aluminum (Al) particles have been widely applied in aerospace and missile technologies, the critical factors influencing their combustion remain insufficiently studied. To address this, this work investigates the effects of multiple factors on Al particle combustion through thermodynamic theoretical calculations and experimental approaches. Thermodynamic results indicate that various oxidizing gases can chemically react with Al and release heat. Among them, the reaction between Al and oxygen exhibits the largest enthalpy change and Gibbs free energy change. In both Al/O and Al/O/C/H systems, increasing temperature reduces enthalpy change but enhances Gibbs free energy change. Pressure shows negligible effects on the system, while the influence of Al molar quantity depends on oxygen atom availability. Thermal analysis reveals that smaller particle sizes significantly increase oxidation rates. Moreover, Al particles with different particle sizes can continue to react until complete oxidation at a constant temperature of 1400 °C in air, suggesting that the alumina shell at high temperatures may be loose and porous with a non-dense structure. Combustion tests demonstrate that reducing particle size from 25 μm to 0.1 μm decreases ignition delay time by 86% and increases combustion temperature by 30%. Similarly, elevating oxygen concentration or pressure reduces ignition delay, enhances combustion temperature, and improves combustion efficiency. This study provides fundamental data support for constructing Al particle combustion models under complex variable environments.
研究领域:
航空航天工程
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燃烧科学
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材料科学
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热力学
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化学反应工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2023
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IF 6.7
Desheng Yang,Chaofei Bai,Jiaran Liu,Shengnan Li,Chengzhao Tu,Fengdan Zhu,Guoping Li,Yunjun Luo,Tianfu Zhang
The construction of ordered pore structure and heterostructure interface is considered as an effective strategy to optimize the activity and stability of nano catalysts. Herein, we have elaborately fabricated the p-n heterostructure nanocatalysts of three-dimensionally ordered macroporous (3DOM) Fe 2 O 3 -supported 2D copper oxide nanofilm using a simple impregnation method, abbreviated as 3DOM-Fe 2 O 3 /CuO. The prepared 3DOM Fe 2 O 3 /CuO shows interconnected and ordered macroporous channels, which provide considerable catalytic active sites and enrich the reactive oxygen concentration at the Fe 2 O 3 -CuO heterostructure interface. By adjusting the copper source concentration, 2D copper oxide nanofilm with varied thicknesses was introduced to readily regulate the morphology of the catalyst and the atom composition or electronic structure of the interface. When evaluated as a catalyst for ammonium perchlorate (AP) decomposition reaction, 3DOM-Fe 2 O 3 /CuO-3 testified the most satisfactory catalytic activity, reducing the high temperature decomposition peak of AP decreased by 105.27 °C and the decomposition activation energy (Ea) by 50 %. Based on the experimental results of this study and related theoretical researches, the following mechanisms are proposed: in the thermal decomposition process of AP, the generation of active oxygen is not only related to the active oxygen mechanism, but also may be related to the NO 2 -assisted mechanism.
研究领域:
材料科学
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催化
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纳米技术
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Atmospheric Pollution Research
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2021
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IF 4.352
Ranran Zhao,Qixing Zhang,Xuezhe Xu,Weixiong Zhao,Hui Yu,Wenjia Wang,Yongming Zhang,Weijun Zhang
As global air pollution aggravates, it urges us to investigate the evolution of atmospheric related emissions. Recently oxidation flow reactor (OFR) has been widely used to simulate the aging of atmospheric related emissions as its excellent performance. In this work, we systematically characterized the SOA formation from α-pinene using a custom-built OFR under different conditions. The particle loss of the OFR was evaluated by particle transmission efficiency, then the effect of O 3 concentration, relative humidity (RH), precursor amounts, OH exposure level, and acidic seed aerosol on SOA formation was investigated. The particle losses of our OFR for particles above 50 nm were very small, which was comparable to or even better than those of previous traditional flow reactors. The formation of SOA particles nearly achieved stability after UV radiation for 15 min. When OH exposure concentration at approximately 0.6 × 10 12 molec cm −3 s, the SOA yield reached the maximum yield of 0.51 and 0.39 in the presence and absence of acidic seed aerosol respectively. The addition of acidic seed aerosol increased both particle number concentration and particle size, resulting in an increase of SOA yield of 1.2–1.5 times at OH exposure concentration ranged from 0.1 × 10 12 to 1.8 × 10 12 molec cm −3 s. The results provided significant guidance for studying the aging of atmospheric related emission under different working conditions by using an OFR.
研究领域:
大气科学
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环境科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2020
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IF 10.652
Ge Xie,Nuoya Zhou,Yujie Gao,Shuo Du,Hongyao Du,Juan Tao,Lianbin Zhang,Jintao Zhu
Acceleration of skin wound healing is an important aspect of wound treatment. The use of carbon dioxide (CO 2 ) has been recognized as one of the most effective ways to improve microcirculation and to benefit wound healing, while the need of the specialized equipment and the uncontrollable delivery of gas CO 2 might restrict such strategy in wide applications. Herein, we develop a photothermal hydrogel for the on-demand and localized delivery of CO 2 to accelerate skin wound healing by combining thermoresponsive block copolymer (BCP) of Pluronic F127 and carbon nanoparticles (CNPs) with amino groups, which can be used for loading CO 2 precursor of bicarbonate for controlled release. We show that by rationally optimizing the content of the thermoresponsive BCP in the photothermal hydrogel, a liquid-to-solid transition triggered by the body temperature can be achieved. Under light irradiation, the CNPs can convert light into heat, triggering the decomposition of the bicarbonate, and the photothermal hydrogel can thus locally release CO 2 in the wound site. Wound healing can be accelerated by improving local microcirculation disturbance and increasing tissue oxygen concentration. This study provides a new opportunity for local CO 2 supplement for accelerating wound healing.
研究领域:
材料科学
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生物医学工程
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伤口愈合
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
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2025
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IF 4.2
Yuanyuan Tian,Xinyang Zhang,Enze Wu,Shengli Liu,Bo Zhang
In this study, amorphous TiO 2 nanofilm has been prepared by a pulsed magnetron sputtering method. The uniform amorphous TiO 2 nanostructure shows the excellent electrochromic performance in visible and near-infrared bands, including the wide transmittance modulations of 63.4 % at 460 nm and 22.1 % at 2000 nm, the short switching time of 9.4 s/8.6 s for coloring/bleaching, and the large coloration efficiency of 62.4 cm 2 /C at 460 nm. Furthermore, the amorphous TiO 2 nanofilm has the feasible energy storage property. The TiO 2 film exhibits a large areal capacitance with good rate performance (9.3 mF/cm 2 ). It provides an intuitive method for monitoring energy storage through changes in TiO 2 electrode color. In addition, the oxygen concentration and sputtered time have significant effects on the microstructure, crystallization and electrochemical properties of TiO 2 films. These results have significant guiding significance for the development of amorphous TiO 2 films and related advanced dual functional devices with electrochromism and energy storage.
研究领域:
材料科学
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电化学
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纳米技术
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光学材料
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薄膜技术
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2024
·
IF 3.9
Xiaoying Zhou,Shiyu Fang,Zihao Hu,Zuliang Wu,Jing Li,Wei Wang,Jiali Zhu,Shuiliang Yao,Erhao Gao
This study introduces a novel catalyst system comprising Pd nanoparticles loaded onto Mn-doped NiO for the efficient oxidation of methane (CH 4 ) at low temperatures. The loading of Pd nanoparticles onto the Mn-doped support has yielded a catalyst with exceptional activity and stability, as evidenced by the lowest T 50 temperature of 276 °C and a CH 4 conversion reaching 97% at 325 °C. The catalyst demonstrates optimized reaction kinetics with the lowest activation energy of 69.2 kJ mol –1 . The catalyst's superior performance is attributed to the synergistic effects of the Pd/Mn-NiO composite, which include a higher Pd 2+ /Pd 4+ ratio, increased adsorptive oxygen concentration (O ads /O total ), and a reduced Ni 3+ /Ni 2+ ratio. These characteristics collectively enhance the catalytic activity for CH 4 oxidation. The Mars-van Krevelen mechanism underpins the oxidation process, with Pd 2+ identified as the principal active site for CH 4 adsorption and dissociation. Diffuse reflectance infrared Fourier transform spectroscopy coupled with mass spectrometry elucidates the pathway of surface reactive oxygen species in the formation of key intermediates, such as formates, and underscores the accelerated decomposition of carbonate facilitated by the Pd modification on the Mn-NiO surface. The findings signify a significant advancement in the development of catalysts for environmental and energy-related applications, particularly in the mitigation of CH 4 emissions.
研究领域:
催化
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环境科学
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能源
✓ 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）