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Journal of Energy chemistry 2024年第9期96卷 464-471页

作者： Mengmeng Liu Yuanyuan jiang Zhuwei cao Lulu Liu Hong chen Sheng Ye School of Materials and chemistry Anhui Agricultural UniversityHefei 230036AnhuiChina

Molybdenum carbide(Mo_(2)c)is a promising non-noble metal electrocatalyst with electronic structures similar to Pt for hydrogen evolution reaction(HER).However,strong H^(*)adsorption at the Mo sites hinders the improvement of HER ***,we synthesized monodisperse hollow Mo_(2)c nanoreactors,in which the carbon dots(cD)were in situ formed onto the surface of Mo_(2)c through carburization *** to finite element simulation and analysis,the cD@Mo_(2)c possesses better mesoscale diffusion properties than Mo_(2)c *** optimized cD@Mo_(2)c nanoreactor demonstrates superior HER performance in alkaline electrolyte with a low overpotential of 57 mV at 10 mA cm^(−2),which is better than most Mo_(2)c-based ***,cD@Mo_(2)c exhibits excellent electrochemical stability during 240 h,confirmed by operando Raman and X-ray diffraction(XRD).Density functional theory(DFT)calculations show that carbon dots cause the d-band center of cD@Mo_(2)c to shift away from Fermi level,promoting water dissociation and the desorption of H^(*).This study provides a reasonable strategy towards high-activity Mo-based HER eletrocatalysts by modulating the strength of Mo–H bonds.

关键词： Mo_(2)c nanoreactor carbon dots H^(*)desorption Electrocatalytic hydrogen evolution

Insight into the Role of Isolated Gold Atoms-ceria conjunction in catalyzing the Water-Gas Shift Reaction

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chinese Journal of chemistry 2024年第6期42卷 636-644页

作者： Xin-Pu Fu Hui-Zhao Wei-Wei Wang chun-jiang Jia Key Laboratory for colloid and Interface chemistry Key Laboratory of Special Aggregated MaterialsSchool of Chemistry and Chemical EngineeringShandong UniversityJinanShandong250100 China

As the promising catalysts for the water-gas shift(WGS)reaction,the activity of Au-ceO_(2) composites is susceptible to the aggregation size and electronic state of Au *** reports were extensively focused on the discrepancy between nonmetallic Au and metallic Au nanoparticles,whereas the understanding of the authentic role of the isolated Au atoms was ***,we investigated the catalytic behavior and structural information over two types of Au/ceO_(2) catalysts,in which the predominant conjunctions were isolated Au1-ceO_(2) and Aun-ceO_(2),*** on comprehensive characterizations,particularly by in-situ Raman and in-situ DRIFTS,we found that the isolated Au atoms were responsible for enhancing the reducibility of the ceO_(2) *** cO adsorption ability on the isolated Au sites was significantly inferior to clustered Au atoms,especially at relatively high temperatures(>200°c).As a result,the boosted O vacancy on the isolated Au1-ceO_(2) conjunctions could improve the H2O activation ability for the Au-ceO_(2) catalysts and demonstrate a comparable activity to the clustered Aun-ceO_(2) *** work might deepen understanding of the catalytic function for the isolated Au1 site within Au/ceO_(2) systems while catalyzing the WGS reaction.

关键词： Isolated Au atoms ceria-based catalysts Water-gas shift reaction Defect Adsorption

EFFEcT OF MODIFIcATION ON cARBIDE GRANULATION AND ITS MEcHANISM

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Acta Metallurgica Sinica(English Letters) 1999年第2期12卷 167-172页

作者： Wang, S.Q. jiang, Q.c. cui, X.H. He, Z.M. Jilin Univ of Technology Changchun China

By the modification, network carbide is disconnected at 1100 degree c through uneven dissolution at higher energy places in carbide, where there is twin or lattice distortion, and is granulated at 1130 degree c through element diffusion. The stability of M//7c//3 carbide is decreased because of the modification reducing the segregation of cr and Mo, thus the temperature, at which uneven dissolution of carbide commenced, is decreased. Also lattice distortion or defect such as twin in carbide is increased by the modification, which prompts widespread disconnections in carbide. In addition, the modification prompts element diffusion to accelerate the kinetics process of carbide granulation. (Edited author abstract) 6 Refs.

关键词： carbides chromium alloys Granulation Modification Morphology

STUDY ON GRANULATION MEcHANISMS OF γ+(Fe,Mn)3c EUTEcTIcS IN AUSTENITE STEEL cOMPOSITES

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Acta Metallurgica Sinica(English Letters) 2003年第6期16卷 449-456页

作者： G.F.Liang Z.M.Xu Q.c.jiang J.G.Li SchoolofMaterialsScienceandTechnology ShanghaiJiaotongUniversityShanghai200030China SchoolofMaterialsScience JilinUniversityChangchun130025China

Results presented in this paper contribute to investigation of the granulation mechanisms of γ+(Fe,Mn)3c eutectics in the austenite matrix composites (abbreviated EAMc). The specimens corresponding to the nominal composition of eutectic with controlled RE(ce)-Mg agent modifier additions have been unidirectional solidified with a constant growth rate of 2.18μm/s at a fixed temperature gradient of 800K/cm using vertical Bridgeman method. With the RE-Mg agent modifier, the transition of solid/liquid (S/L) interface from columnar to dendrite (cDT), refinement and developed branching of γ and (Fe,Mn)3c phases in the eutectics, and the transition of growth style from faceted-nonfaceted (F/NF) to nonfaceted-nonfaceted (NF/NF) for γ and (Fe,Mn)3c phases in the eutectic have been observed and investigated theoretically. Those can explain the granulation of γ+(Fe,Mn)3c eutectics in the as cast because the roundness increases with the developed lateral branching of primary austenite dendrites, refinement of eutectics, and NF/NF growth of γ and (Fe,Mn)3c phases in the eutectic.

关键词： composite RE-Mg agent granulation unidirectional solidifica-tion

IMPROVEMENT OF cARBIDE MORPHOLOGY ANDMEcHANIcAL PROPERTIES OF cr12MoV STEELS

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Acta Metallurgica Sinica(English Letters) 2000年第5期13卷 1053-1058页

作者： cui, X.H. jiang, Q.c. Wang, S.Q. He, Z.M. Sch. of Mat. Sci. and Eng. Jilin Univ. of Technol. Changchun 130025 China

compared with conventional cast cr12MoV steel and forged cr12MoV steels, carbide morphology and properties of modified cast cr12MoV steels were investigated by performing hardness test, impact test, fracture toughness test, fatigue crack propagation test, metallographic examination and quantitatively metallographic analysis. The results indicate that the carbide morphology in modified cast steel is characterized by uniformly-distributed granular carbide, which is different from that of conventional cast steel, but similar to that of forged steel. the impact toughness of modified cast steel is distinctly increased to 12.75 J/cm2 from 6.8 J/cm2 in the conventional cast steel with networked carbide, because of carbide granulation. Furthermore, The fracture toughness and fatigue-crack-propagation threshold of modified cast steel are not only higher than that of the conventional cast steel, but also higher than that of the forged steels.

关键词： Alloys carbides Mechanical properties Morphology

SIMULATION OF LARGE TURBINE ROTOR'S HEAT TREATMENT PROcESS

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Acta Metallurgica Sinica(English Letters) 2005年第6期18卷 768-772页

作者： c. jiang Y.B. chen B.S. Wu Q.L. Jin Beijing Research Institute of Mechanical and Electrical Technology Beijing 100083 China

Temperature field numerical simulation about he heat treatment process curve of large turbine rotor is presented. With simulation software Deform3D in according to the heat treatment processing of china First Heavy Machinery, the details of temperature change at the different location of the rotor is to be found. Once knowing the temperature field change, the duplex grain defect long time existed in large forgings can be solved with a quantitative analysis instead of only the qualitative one. Precondition for small metal samples is brought to simulate microstructare and grain size change of large rotor according to the numerical simulation result. Also, consistent feature with real manufacture is showed from the physical experiment, so that the simulation can be used to not only improve the products process but also prevent wasting unnecessary energy and shorten process periods. The rotor quality is controlled thoroughly with plenty of experiments data.

关键词： temperature field numerical simulation grain size

Artificial synthesis of polyesters at ambient condition via consecutive cO_(2)electrolysis and fermentation

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Nano Research 2024年第7期17卷 6016-6025页

作者： Guiru Zhang Ning Ji Shiheng Lyu Baoxin Ni Peng Shen Ke Ye Yuting Wang Xuheng jiang Hai Zhang Xi Liu Yongcheng Wang Kun jiang Department of Laboratory Medicine of The First Affiliated Hospital&Liangzhu Laboratory Zhejiang University School of MedicineHangzhou 310058China Interdisciplinary Research center School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China In-situ centre for Physical Sciences Frontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Electrochemically converting cO_(2)into value-added chemicals is a promising approach to mitigate anthropogenic carbon emissions,yet largely limited to short-chained c_(1)–c_(3)***,we demonstrate a tandem artificial synthesis of biodegradable polyhydroxybutyrate(PHB)plastic from cO_(2)building *** synthesis of defects-enriched Bi catalyst is firstly demonstrated by plasma bombardment and following in situ electrochemical reduction,which delivers a HcOOH Faradaic efficiency above 80%at tunable concentration from 2 to 250 mM,an energy efficiency up to 41%,and a single-pass carbon conversion efficiency up to 60%.Annular dark field and second electron microscopic analysis,density functional theory(DFT)calcualtions,coupled with H-type and solid-state electrolyzer assessments,point out the vital role of defective and/or stepped Bi surface sites in promoting cO_(2)-to-HcOOH ***,as-synthesized high-purity HcOOH is used as the sole carbon source for c-chain growth within microbial fermentation reactor with Ralstonia eutropha,where activated formate dehydrogenase and increased metabolites related to calvin–Benson–Bassham cycle are found to be responsible for the enhanced polyester accumulation.

关键词： cO_(2)electrolysis Bi catalyst vacancy site formic acid fermentation

Ionic liquid-trimetallic electrocatalytic system for c–O bond cleavage in lignin model compounds and lignin under ambient conditions

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Nano Research 2024年第4期17卷 2420-2428页

作者： Guangyong Liu Yumiao Lu JunFeng Lu Yanlei Wang Shijing Liang Hongyan He Lilong jiang National Engineering Research center of chemical Fertilizer catalyst Fuzhou UniversityFuzhou 350002China cAS Key Laboratory of Green Process and Engineering State Key Laboratory of Multiphase Complex SystemsBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Longzihu New Energy Laboratory Zhengzhou Institute of Emerging Industrial TechnologyZhengzhou 450000China

Electrocatalytic depolymerization of lignin into value-added chemicals offers a promising technique to make biorefining ***,we report a robust trimetallic PdNiBi electrocatalyst for reductive c–O bond cleavage of different lignin model dimers and oxidized lignin under mild *** reduction reaction proceeds with complete substrate conversion and excellent yields toward monomers of phenols(80%–99%)and acetophenones(75%–96%)in the presence of an ionic liquid electrolyte with operational *** experimental investigations together with density functional theory(DFT)calculations reveal that the outstanding performance of the catalyst results from the synergistic effect of the metal elements,which facilitates the easier formation of a key cαradical intermediate and the facile desorption of the as-formed products at the *** results open up new opportunities for lignin valorization through the green electrocatalytic approach.

关键词： electrocatalytic depolymerization lignin Ionic liquids density functional theory(DFT)calculation

copper-based nanomaterials as peroxidase candidates for intelligent colorimetric detection and antibacterial applications

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Particuology 2024年第1期84卷 126-135页

作者： Yanyan Huang Huimin Zhong cong jiang Jiahui Yang Jingwen Zhang Fei Zhao chaoqun Liu college of Light Industry and Food Engineering Nanjing Forestry UniversityNanjing210037China college of Pharmacy Institutes of Environment and MedicineHenan UniversityKaifeng475004China

With natural polyphenol compound tannic acid(TA)as the ingredient,copper tannate(cuTA)nanolayer material was formed by self-assembly under the conditions of heating and copper *** ion and tannic acid could coordinate to form cu-O-c structure which was similar to the Fe-N-c structure of natural heme *** addition,the obtained cuTA nanomaterial possessed excellent peroxidase-like catalytic activity and *** on this excellent enzymatic activity,cuTA nanomaterials could be used for colorimetric detection of hydrogen peroxide with a smartphone and decomposition of organic *** on the structural characteristics and catalytic activity,the copper tannate nanozymes could also serve as potential antibacterial reagents to effectively inhibit the growth of gram-negative and positive bacteria in a low hydrogen peroxide *** work may promote the exploration of novel peroxidase mimetics and broaden the applications of nanozymes.

关键词： Nanozyme colorimetric detection Smartphone Antibacteria

Metal-organic framework hybrid materials of ZIF-8/RGO for immobilization of D-amino acid dehydrogenase

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Nano Research 2024年第1期17卷 290-296页

作者： Hangbin Lei Qian Zhang Xiaoyan Xiang Liang jiang Shiyan Wang Lingxuan Duan Shizhen Wang Department of chemical and Biochemical Engineering College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Xiamen Key Laboratory of Synthetic Biotechnology Xiamen UniversityXiamen 361005China

Immobilization of D-amino acid dehydrogenase(DAADH)by the assembly of peptide linker was studied for the biosynthesis of *** material of zeolitic imidazolate framework-8(ZIF-8)combined with reduced graphene oxide(RGO)was applied for the immobilization of DAADH from Ureibacillus *** recovery rate of DAADH/ZIF-8/RGO was 165.6%.DAADH/ZIF-8/RGO remained 53.4%of its initial activity at 50°c for 10 h while the free enzyme was ***/ZIF-8/RGO maintained 70.5%activity in hyperalkaline solution with pH *** parameters indicated that DAADH/ZIF-8/RGO had greater affinity of phenylpyruvate as V_(max)/K_(m)of DAADH/ZIF-8/RGO was 1.27-fold than free *** seven recycles,the activity of DAADH/ZIF-8/RGO remained 64.3%.Furthermore,one-step separation and in situ immobilization of DAADH by ZIF-8/RGO/Ni was carried out with 1.5-fold activity *** peptide linker and metal-organic framework(MOF)immobilization,thermostability and activity of the immobilized DAADH were significantly improved.

关键词： D-Amino acid dehydrogenase immobilization metal-organic frameworks zeolitic imidazolate framework-8(ZIF-8) reduced graphene oxide