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过硫酸盐诱导的缺陷氮化碳中三配位氮（N3_C）空位增强光催化产过氧化氢 Article

缪蔚, 王奕杰, 刘莹, 秦贺贺, 褚成成, 毛舜

《工程（英文）》 2023年第25卷第6期页码 214-221 doi: 10.1016/j.eng.2021.12.016

摘要：然而，由于g-C₃N₄中不同类型的氮空位对光催化活性的影响方式不同，氮空位的光催化作用机制尚不清楚。在此，本文提出了一种简便的过硫酸钠共晶聚合方法，制备了具有丰富三配位氮空位（N3_C）的g-C₃N₄。本研究的结果表明，在g-C₃N₄中引入N3_C空位可以成功地拓宽光吸收范围，抑制光激发电荷的重组，增强O₂的吸附和活化富含N3_C空位的g-C₃N₄的光催化过氧化氢产量是原始g-C₃N₄的4.5倍。本研究提出了在g-C₃N₄中引入N3_C空位的新策略，为开发光催化产过氧化氢的活性催化剂提供了一种新方法。

关键词：氮化碳 N3_C空位过氧化氢光催化过硫酸盐

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Effect of noble metal nanoparticle size on C–N bond cleavage performance in hydrodenitrogenation: a study

《化学科学与工程前沿（英文）》 2023年第17卷第12期页码 1986-2000 doi: 10.1007/s11705-023-2337-5

摘要： Breakage of the C–N bond is a structure sensitive process, and the catalyst size significantly affects its activity. On the active metal nanoparticle scale, the role of catalyst size in C–N bond cleavage has not been clearly elucidated. So, Ru catalysts with variable nanoparticle sizes were obtained by modulating the reduction temperature, and the catalytic activity was evaluated using 1,2,3,4-tetrahydroquinoline and o-propylaniline with different C–N bond hybridization patterns as reactants. Results showed a 13 times higher reaction rate for sp³-hybridized C–N bond cleavage than sp²-hybridized C–N bond cleavage, while the reaction rate tended to increase first and then decrease as the catalyst nanoparticle size increased. Different concentrations of terrace, step, and corner sites were found in different sizes of Ru nanoparticles. The relationship between catalytic site variation and C–N bond cleavage activity was further investigated by calculating the turnover frequency values for each site. This analysis indicates that the variation of different sites on the catalyst is the intrinsic factor of the size dependence of C–N bond cleavage activity, and the step atoms are the active sites for the C–N bond cleavage. When Ru nanoparticles are smaller than 1.9 nm, they have a strong adsorption effect on the reactants, which will affect the catalytic performance of the Ru catalyst. Furthermore, these findings were also confirmed on other metallic Pd/Pt catalysts. The role of step sites in C–N bond cleavage was proposed using the density function theory calculations. The reactants have stronger adsorption energies on the step atoms, and step atoms have d-band center nearer to the Fermi level. In this case, the interaction with the reactant is stronger, which is beneficial for activating the C–N bond of the reactant.

关键词： sp³/sp²-hybridized C–N bond noble metal nanoparticle catalytic active site turnover frequency DFT

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Enhancing the efficiency of nitrogen removing bacterial population to a wide range of C:N ratio (1.5:1 to 14:1) for simultaneous C & N removal

《环境科学与工程前沿（英文）》 2022年第16卷第8期 doi: 10.1007/s11783-022-1522-y

摘要：

• Simultaneous C & N removal in Methammox occurs at wide C:N ratio.

关键词： Methanogens Biological Nitrogen Removal (BNR) Simultaneous Methammox C:N ratio

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Recent advances in special morphologic photocatalysts for NO removal

《环境科学与工程前沿（英文）》 2022年第16卷第11期 doi: 10.1007/s11783-022-1573-0

摘要：

● Systematic information of recent progress in photocatalytic NO_x removal is provided.

关键词： NO_x removal Photocatalyst Graphene C₃N₄ Bi-based compounds.

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基于S3C2410的GPRS数据终端的设计

孙学用

《中国工程科学》 2007年第9卷第12期页码 94-96

摘要：提出了以S3C2410处理器为核心，以SIM100-E为GPRS通信模块,构建了一套嵌入式Internet数据终端的方案，对其硬件构成及工作流程进行了讨论，描述了其软件层次结构，并详细讲解了基于该平台的

关键词： GPRS；嵌入式Internet；S3C2410；SIM100-E

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第四届高性能编译、计算和通信国际会议(HP3C 2020)

会议日期： 2020年03月12日

会议地点：广东广州

主办单位： HP3C 2020

Tuning nitrogen defects and doping sulfur in carbon nitride for enhanced visible light photocatalytic activity

《化学科学与工程前沿（英文）》 2023年第17卷第1期页码 93-101 doi: 10.1007/s11705-022-2175-x

摘要： Defect construction and heteroatom doping are effective strategies for improving photocatalytic activity of carbon nitride (g-C₃N₄). In this work, N defects were successfully prepared via cold plasma. High-energy electrons generated by plasma can produce N defects and embed sulfur atoms into g-C₃N₄. The N defects obviously promoted photocatalytic degradation performance that was 7.5 times higher than that of pure g-C₃N₄. The concentration of N defects can be tuned by different power and time of plasma. With the increase in N defects, the photocatalytic activity showed a volcanic trend. The g-C₃N₄ with moderate concentration of N defects exhibited the highest photocatalytic activity. S-doped g-C₃N₄ exhibited 11.25 times higher photocatalytic activity than pure g-C₃N₄. It provided extra active sites for photocatalytic reaction and improved stability of N defects. The N vacancy-enriched and S-doped g-C₃N₄ are beneficial for widening absorption edge and improving the separation efficiency of electron and holes.

关键词： g-C₃N₄ nitrogen defect sulfur doping photodegradation plasma

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Scrap Iron Filings assisted nitrate and phosphate removal in low C/N waters using mixed microbial culture

《环境科学与工程前沿（英文）》 2021年第15卷第4期 doi: 10.1007/s11783-020-1358-2

摘要：

• Microbes enhance denitrification under varying DO concentrations and SIF dosages.

关键词： Scrap iron filing Nitrate removal Phosphate removal Mixed culture denitrification Zero valent iron

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Performance of iron-air battery with iron nanoparticle-encapsulated C–N composite electrode

《能源前沿（英文）》 doi: 10.1007/s11708-023-0913-5

摘要： Highly efficient and stable iron electrodes are of great significant to the development of iron-air battery (IAB). In this paper, iron nanoparticle-encapsulated C–N composite (NanoFe@CN) was synthesized by pyrolysis using polyaniline as the C–N source. Electrochemical performance of the NanoFe@CN in different electrolytes (alkaline, neutral, and quasi-neutral) was investigated via cyclic voltammetry (CV). The IAB was assembled with NanoFe@CN as the anode and IrO₂ + Pt/C as the cathode. The effects of different discharging/charging current densities and electrolytes on the battery performance were also studied. Neutral K₂SO₄ electrolyte can effectively suppress the passivation of iron electrode, and the battery showed a good cycling stability during 180 charging/discharging cycles. Compared to the pure nano-iron (NanoFe) battery, the NanoFe@CN battery has a more stable cycling stability either in KOH or NH₄Cl + KCl electrolyte.

关键词： energy storage and conversion metallic composites nanocomposites iron-air battery iron anode

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Cracking evolution behaviors of lightweight materials based on

C. Wu, Y. N. Hu, Y. N. Fu

《机械工程前沿（英文）》 2018年第13卷第4期页码 461-481 doi: 10.1007/s11465-018-0481-2

摘要：

Damage accumulation and failure behaviors are crucial concerns during the design and service of a critical component, leading researchers and engineers to thoroughly identifying the crack evolution. Third-generation synchrotron radiation X-ray computed microtomography can be used to detect the inner damage evolution of a large-density material or component. This paper provides a brief review of studying the crack initiation and propagation inside lightweight materials with advanced synchrotron three-dimensional (3D) X-ray imaging, such as aluminum materials. Various damage modes under both static and dynamic loading are elucidated for pure aluminum, aluminum alloy matrix, aluminum alloy metal matrix composite, and aluminum alloy welded joint. For aluminum alloy matrix, metallurgical defects (porosity, void, inclusion, precipitate, etc.) or artificial defects (notch, scratch, pit, etc.) strongly affect the crack initiation and propagation. For aluminum alloy metal matrix composites, the fracture occurs either from the particle debonding or voids at the particle/matrix interface, and the void evolution is closely related with fatigued cycles. For the hybrid laser welded aluminum alloy, fatigue cracks usually initiate from gas pores located at the surface or sub-surface and gradually propagate to a quarter ellipse or a typical semi-ellipse profile.

关键词： fatigue crack initiation and growth fatigue damage mechanism damage tolerance defect characterization laser welded aluminum alloys

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Pd/Fe3O4 supported on bio-waste derived cellulosic-carbon as a nanocatalyst for C–C coupling and electrocatalytic

《化学科学与工程前沿（英文）》 2022年第16卷第10期页码 1514-1525 doi: 10.1007/s11705-022-2158-y

摘要： The current work describes the synthesis of a new bio-waste derived cellulosic-carbon supported-palladium nanoparticles enriched magnetic nanocatalyst (Pd/Fe₃O₄@C) using a simple multi-step process under aerobic conditions. Under mild reaction conditions, the Pd/Fe₃O₄@C magnetic nanocatalyst demonstrated excellent catalytic activity in the Hiyama cross-coupling reaction for a variety of substrates. Also, the Pd/Fe₃O₄@C magnetic nanocatalyst exhibited excellent catalytic activity up to five recycles without significant catalytic activity loss in the Hiyama cross-coupling reaction. Also, we explored the use of Pd/Fe₃O₄@C magnetic nanocatalyst as an electrocatalyst for hydrogen evolution reaction. Interestingly, the Pd/Fe₃O₄@C magnetic nanocatalyst exhibited better electrochemical activity compared to bare carbon and magnetite (Fe₃O₄ nanoparticles) with an overpotential of 293 mV at a current density of 10 mA·cm^–2.

关键词： bio-waste cellulosic-carbon Pd/Fe₃O₄ Hiyama cross-coupling hydrogen evolution reaction recyclability

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New insight into effect of potential on degradation of Fe-N-C catalyst for ORR

Yanyan GAO, Manman QI, Liang HE, Haiping CHEN, Wenzhe LUO, Ming HOU, Zhigang SHAO

《能源前沿（英文）》 2021年第15卷第2期页码 421-430 doi: 10.1007/s11708-021-0727-2

摘要： In recent years, Fe-N-C catalyst is particularly attractive due to its high oxygen reduction reaction (ORR) activity and low cost for proton exchange membrane fuel cells (PEMFCs). However, the durability problems still pose challenge to the application of Fe-N-C catalyst. Although considerable work has been done to investigate the degradation mechanisms of Fe-N-C catalyst, most of them are simply focused on the active-site decay, the carbon oxidation, and the demetalation problems. In fact, the 2e pathway in the ORR process of Fe-N-C catalyst would result in the formation of H O , which is proved to be a key degradation source. In this paper, a new insight into the effect of potential on degradation of Fe-N-C catalyst was provided by quantifying the H O intermediate. In this case, stability tests were conducted by the potential-static method in O saturated 0.1 mol/L HClO . During the tests, H O was quantified by rotating ring disk electrode (RRDE). The results show that compared with the loading voltage of 0.4 V, 0.8 V, and 1.0 V, the catalysts being kept at 0.6 V exhibit a highest H O yield. It is found that it is the combined effect of electrochemical oxidation and chemical oxidation (by aggressive radicals like H O /radicals) that triggered the highest H O release rate, with the latter as the major cause.

关键词： proton exchange membrane fuel cells (PEMFCs) oxygen reduction reaction (ORR) Fe-N-C catalyst potential H₂O₂ degradation

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Multi-functional 3D N-doped TiO

Zijian Cui, Kaiyue Zhang, Guangyu Xing, Yaqing Feng, Shuxian Meng

《化学科学与工程前沿（英文）》 2017年第11卷第3期页码 395-404 doi: 10.1007/s11705-017-1643-1

摘要： Three-dimensional TiO microspheres doped with N were synthesized by a simple single-step solvothermal method and the sample treated for 15 h (hereafter called TMF) was then used as scattering layers in the photoanodes of dye-sensitized solar cells (DSSCs). The TMF was characterized using scanning electron microscopy, high resolution transmission electron microscopy, Brunauer-Emmett-Teller measurements, X-ray diffraction, and X-ray photoelectron spectroscopy. The TMF had a high surface area of 93.2 m ·g which was beneficial for more dye-loading. Five photoanode films with different internal structures were fabricated by printing different numbers of TMF scattering layers on fluorine-doped tin oxide glass. UV-vis diffuse reflection spectra, incident photon-to-current efficiencies, photocurrent-voltage curves and electrochemical impedance spectroscopy were used to investigate the optical and electrochemical properties of these photoanodes in DSSCs. The presence of nitrogen in the TMF changed the TMF microstructure, which led to a higher open circuit voltage and a longer electron lifetime. In addition, the presence of the nitrogen significantly improved the light utilization and photocurrent. The highest photoelectric conversion efficiency achieved was 8.08%, which is much higher than that derived from typical P25 nanoparticles (6.52%).

关键词： DSSCs N doping scattering layer electron lifetime

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g-CN-coated MnO hollow nanorod cathode for stable aqueous Zn-ion batteries

《化学科学与工程前沿（英文）》 2023年第17卷第2期页码 217-225 doi: 10.1007/s11705-022-2214-7

摘要： Aqueous zinc-ion batteries are attracting considerable attention because of their high safety compared with conventional lithium-ion batteries. Manganese-based materials have been widely developed for zinc-ion batteries cathode owning to their low cost, high security and simple preparation. However, the severe volume expansion and poor stability during charging and discharging limit the further development of manganese-based cathodes. Herein, superior α-MnO₂@g-C₃N₄ was successfully prepared for stable zinc-ion batteries (ZIBs) cathode by introducing g-C₃N₄ nanosheets. Compared with pure α-MnO₂, α-MnO₂@g-C₃N₄ has a specific capacity of 298 mAh·g^–1 at 0.1 A·g^–1. Even at 1 A·g^–1, the α-MnO₂@g-C₃N₄ still retains 100 mAh·g^–1 (83.4% retention after 5000 cycles), implying its excellent cycling stability. The α-MnO₂@g-C₃N₄-based cathode has the highest energy density (563 Wh·kg^–1) and power energy density (2170 W·kg^–1). This work provides new avenues for the development of a wider range of cathode materials for ZIBs.

关键词： α-MnO₂ hollow nanorods g-C₃N₄ heterojunction aqueous Zn-ion batteries

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Rh₂O₃/hexagonal CePO₄ nanocatalysts for N₂O decomposition

Huan Liu, Zhen Ma

《化学科学与工程前沿（英文）》 2017年第11卷第4期页码 586-593 doi: 10.1007/s11705-017-1659-6

摘要： Hexagonal CePO nanorods were prepared by a precipitation method and hexagonal CePO nanowires were prepared by hydrothermal synthesis at 150 °C. Rh(NO ) was then used as a precursor for the impregnation of Rh O onto these CePO materials. The Rh O supported on the CePO nanowires was much more active for the catalytic decomposition of N O than the Rh O supported on CePO nanorods. The stability of both catalysts as a function of time on stream was studied and the influence of the co-feed (CO , O , H O or O /H O) on the N O decomposition was also investigated. The samples were characterized by N adsorption-desorption, inductively coupled plasma optical emission spectroscopy, X-ray diffraction, transmission electron microscopy, X-ray photoelectron microscopy, hydrogen temperature-programmed reduction, oxygen temperature-programmed desorption, and CO temperature-programmed desorption in order to correlate the physicochemical and catalytic properties.

关键词： Rh₂O₃ CePO₄ N₂O decomposition