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Directly imaging the in-situ chemical transformation of nickel cubane nanoclusters for promoting electrocatalytic urea-oxidation reaction

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Nano Research 2025年第2期18卷 218-226页

作者： En-Xue Liu Hong-Hao Li Cheng Hou Jian-Qiang Zhao Mohamedally Kurmoo Yi-Jing Gao Zheng Yin Bin Zhang Ming-hua zeng State Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China Hubei Collaborative Innovation Center for Advanced Chemical Materials Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules and College of Chemistry and Chemical EngineeringHubei UniversityWuhan 430062China Zhejiang Engineering Laboratory for Green Syntheses and Applications of Fluorine-Containing Specialty Chemicals Institute of Advanced Fluorine-Containing MaterialsZhejiang Normal UniversityJinhua 321004China Institute de Chimie de Strasbourg CNRS-UMR7177Universitéde Strasbourg4 rue Blaise PascalStrasbourg 67070France

We report the stepwise in-situ manipulation of a nickel cubane nanocluster capped with a specially designed multidentate ligand [Ni^(Ⅱ)_(4)(HL)_(3)(CH_(3)O)(CH_(3)OH)_(3)](CH_(3)COO)(Ni_(4),H_(3)L=(E)-3-((2-hydroxy-3-mehoxybenzylidene)amino)propane-1,2-diol) to firstly [Ni^(Ⅱ)_(4)(HL)_(3)(CH_(3)O)(CH_(3)OH)_(2)(H_(2)O)](CH_(3)COO)(Ni4-1min) and finally to [Ni^(Ⅱ)_(4)(HL)_(3)(CH_(3)O)(H_(2)O)_(3)](CH_(3)COO)Ni4-20h)during the urea electrolysis.A combination of mass spectrometry,single crystallography and pair distribution function were employed to analyze the structural correlations of this catalyst in crystal/solution/gas phases for confirming the dynamic ligand replacement while preserving the cubic Ni4 core during *** key feature of their structures is that:(i)three ligands wrap the Ni_(4)O_(4)cubane center on one side forming the rounded outside of a calix;(ii)the opposite flat side containing labile methanol as the active *** structure facilitates the binding of the substrate to the active central nickel atoms during ***,due to the different modes of packing,the structure of Ni4-20 h sustains two-dimensional(2D)net of open space while the structures of Ni4 and Ni4-1 min have only closed void inaccessible to solvent molecules or ***,the overpotential initially decreased(up to 45 min)until it is *** result showed a low potential of 1.32 V(urea oxidation reaction(UOR))at 10 mA·cm^(-2)as reflected in the Gibbs free energy decrease of~0.4 eV from Ni4 to Ni4-20 *** work demonstrates a convincing approach for elucidating the exact nature of the active clusters in electrocatalytic process,and confirms that in-situ modification of electrode materials might alter the direct electronic interaction between substrate and active sites in improving the catalytic performance.

关键词： atomically precise nanocluster nickel cubane electrode modification urea oxidation reaction

In-situ evolution process understanding from a salan-ligated manganese cluster to supercapacitive application

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Nano Research 2022年第1期15卷 346-351页

作者： Xu Zhang Kai Zhao Xu Peng Mohamedally Kurmoo Ming-hua zeng Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules&College of Chemistry&Chemical EngineeringHubei UniversityWuhan 430062China Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China Institut de Chimie de Strasbourg CNRS-UMR7177Universite de Strasbourg4 rue Blaise Pascal67070 Strasbourg CedexFrance

The goal of material chemistry is to study the relationship among hierarchical structure,chemical reaction and precision preparation for materials,yet tracking pyrolysis process on multi-dimensional scale is still at primary *** we propose packing mode analysis to understand evolution process in high temperature *** a proof of concept,we first design a salan-ligated Mn3(Mn3(3-MeOsalophen)_(2)(Cl)_(2))cluster and pyrolyze it under an inert atmosphere directly to a mixed valence MnOx embedded in a porous N-doped carbon skeleton(MnOx/C).Meanwhile,combining thermogravimetry-mass spectrometry(TG-MS)with other characterization techniques,its pyrolysis process is precisely tracked real-time and Mn^(2+)/Mn^(3+)ratios in the resulting materials are deduced,ensuring excellent electrochemical *** a result,the as-preferred MnOVC-900 sample reaches 943 F/g at 1 A/g,maintaining good durability under 5,000 cycles with 90%*** highlight of packing mode analysis strategy in this work would provide a favorable approach to explore the potential relationship between structure and performance in the future.

关键词： evolution process understanding thermogravimetry-mass spectrometry salan-ligated manganese cluster packing mode analysis supercapacitive performance

CuBr-promoted domino Biginelli reaction for the diastereoselective synthesis of bridged polyheterocycles:Mechanism studies and in vitro anti-tumor activities

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Chinese Chemical Letters 2022年第11期33卷 4891-4895页

作者： Mengting zeng Ying Xue Yunan Qin Fen Peng Quan Li Ming-hua zeng Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional MoleculesCollege of Chemistry and Chemical EngineeringHubei UniversityWuhan 430062China Sichuan Center for Disease Control and Prevention Chengdu 610041China Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China

The low-cost CuBr-promoted domino Biginelli reaction among readily available ketones,salicylaldehyde derivatives and 3-amino-1,2,4-triazole was studied under solvothermal conditions,giving the novel bridged polyheterocycles bearing two or three stereocenters depending on the starting *** multicomponent reaction proceeded with high diastereoselectivity(dr>20:1)based on a combined~1 H NMR,crystallographic and supercritical fluid chromatographic(SFC)analysis of the ***-dependent high-resolution mass spectrometry(HRMS)was performed to track the reaction process,and several key intermediates were identified,leading to the drawing of a plausible reaction *** functional theory(DFT)calculation was supplemented,and two reaction pathways were ***,in vitro antitumor activity was evaluated using HeLa and HepG2 cell lines,and two of these polyheterocycles demonstrated promising activities against HepG2 cells with EC50 down to 10μmol/***,ESI-MS/MS studies on all the polyheterocycles suggest a common fragmentation pathway(loss of one molecule of amino-triazole)they shared,providing the first-hand fragmentation rules for future rapid structural identification of *** multicomponent domino reaction presented here may offer prospects for future design of more efficient strategies to access medicinally important bridged polyheterocycles.

关键词： Multicomponent reaction Domino reaction Biginelli reaction Bridged polyheterocycles Reaction mechanism Anti-tumor activities

Effects of different mechanical direct seeding methods on grain yield and lodging resistance of early indica rice in South China

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Journal of Integrative Agriculture 2021年第5期20卷 1204-1215页

作者： WANG Wen-xia DU Jie ZHOU Yan-zhi zeng Yong-jun TAN Xue-ming PAN Xiao-hua SHI Qing-hua WU Zi-ming zeng Yan-hua Key Laboratory of Crop Physiology Ecology and Genetic BreedingMinistry of Education/Collaborative Innovation Center for the Modernization Production of Double Cropping RiceCollege of AgronomyJiangxi Agricultural UniversityNanchang 330045P.R.China

Direct seeding of rice has become a main planting method due to the low labor input and high economic benefit in South *** direct seeding(DDS)has been widely used for single-season rice planting ***,few studies have examined the performance of early-season indica rice under mechanical dry direct seeding.A two-year field experiment was conducted with two indica rice cultivars(i.e.,Zhongjiazao 17 and Zhuliangyou 819)to study lodging characteristics and grain yield formation under DDS,flooded direct seeding(FDS)and wet direct seeding(WDS)*** results showed that the annual grain yield in DDS was higher by 14.42–26.34%for cultivar ZLY819 and 6.64–24.58%for cultivar ZJZ17 than in WDS and FDS,respectively,and these increases were mainly attributed to the improvement of the *** DDS pattern significantly increased the seedling emergence rate of early indica rice cultivars,and increased total dry weight and crop growth ***,shorter basal internodes,better stem diameter and stem wall thickness and lower lodging index were found in DDS in contrast to FDS and *** particular,DDS improved the stem lodging *** results suggested that the appropriate direct seeding method was beneficial for improving the grain yield and lodging resistance of early indica rice.

关键词： mechanical dry direct seeding early indica rice grain yield lodging resistance South China

Improved Z^(1/3) Law of Nuclear Charge Radius

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Communications in Theoretical Physics 2009年第1期51卷 123-125页

作者： LEI Yi-An ZHANG Zhen-hua zeng Jin-Yan School of Physics Peking University Beijing 100871 China

An improved Z^1/3 law of nuclear charge radius is presented. The comparison between the calculated and experimental nuclear charge radii now available shows that this new formula is better than the other conventional ... 详细信息

关键词： nuclear charge radius improved Z^1/3 law isospin dependence

Quantum Secure Direct Intercommunication with Superdense Coding and Entanglement Swapping

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Communications in Theoretical Physics 2008年第12期50卷 1290-1294页

作者： huaNG Da-Zu GUO Ying zeng Gui-hua School of Information Science ＆ Engineering Central South University Changsha 410083 China Department of Information Management Hunan College of Finance ＆ Economics Changsha 410205 China State Key Laboratory on Fiber-Optic Local Area Networks and Advanced Optical Communication Systems Department of Electronic Engineering Shanghai Jiaotong University Shanghai 200240 China

A quantum secure direct intercommunication scheme is proposed to exchange directly the communicators＇ secret messages by making ase of swapping entanglement of Bell states. It has great capacity to distribute the secret messages since these messages have been imposed on high-dimensional Bell states via the local unitary operations with superdense coding. The security is ensured by the secure transmission of the travel sequences and the application of entanglement swapping.

关键词： quantum secure direct intercommunication entanglement swapping quantum cryptography

Multi-state Quantum Teleportation via One Entanglement State

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Communications in Theoretical Physics 2008年第8期50卷 363-367页

作者： GUO Ying zeng Gui-hua Moon Ho Lee School of Information Science ＆ Engineering Central South University Changsha 410083 China State Key Laboratory on Fiber-Optic Local Area Networks and Advanced Optical Communication Systems Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China Department of Information ＆ Communication Engineering Chonbuk National University Chonju 561-756 Korea

A multi-sender-controlled quantum teleportation scheme is proposed to teleport several secret quan- tum states from different senders to a distance receiver based on only one Einstein-Podolsky-Rosen (EPR) pair with controlled-NOT (CNOT) *** the present scheme,several secret single-qubit quantum states are encoded into a multi-qubit entangled quantum *** communication modes,i.e.,the detecting mode and the message mode,are employed so that the eavesdropping can be detected easily and the teleported message may be recovered *** has an advantage over teleporting several different quantum states for one scheme run with more efficiency than the previous quantum teleportation schemes.

关键词： quantum teleporlation entanglement state

Exploring the Pyrolysis Mechanism towards OER Performance Optimization of Salophen-ligated Binuclear Cobalt Complex

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Chinese Journal of Chemistry 2021年第9期39卷 2529-2535页

作者： Qi An Bingxin Pan Li Li Xu Peng Ming-hua zeng Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules&College of Chemistry&Chemical EngineeringHubei UniversityWuhanHubei 430062China Department of Chemistry and Pharmaceutical Sciences Guangxi Normal UniversityKey Laboratory for the Chemistry and Molecular Engineering of Medicinal ResourcesGuilinGuangxi 541004China

Exploring pyrolysis process is an efficient way to study the relationship between molecular level of the precursor structure and electrocatalytic functional materials in ***,the unique semi-enclosed sector structure of Salophen ligands with highly symmetric N,N,0,0 mode was introduced to construct binuclear Co complex[Co2(salophen)(CI)2(C2H3N)](compound 1),which provides pre-liminary theoretical basis for the efficient coreshell structure electrocatalysts obtained by pyrolysis ***,we adopted TG-MS to real-time track the pyrolysis process from precursors of binuclear Co complexes with Salophen ligand to efficient catalytic materials with core-shell nano *** expected,the 1-600 sample achieves ultra-low overpote ntial of 256 mV at 10 mA·cm^(-2) and high catalytic stability within 10 h in 1 mol/L KOH *** work highlights salophen-ligated complex as excellent precursor material system for the an alysis of pyrolysis evoluti on process,and provides an opport unity for targeted preparati on of efficie nt oxy-gen evoluti on reacti on(OER)nano catalysts.

关键词： Schiff bases Pyrolysis TG-MS Nanostructures Electrochemistry

Tribological performance and chemistry of films for di-n-butyl dithiocarbamate derivatives in rapeseed oil

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Chinese Science Bulletin 2007年第2期52卷 194-199页

作者： WU hua zeng XiangQiong LU LingBo REN TianHui School of Chemistry and Chemical Engineering Shanghai Jiaotong University Shanghai China

Two di-n-butyl dithiocarbamate derivatives were easily synthesized. Their tribological performances as lubricating oil additives in rapeseed oil were evaluated using a four-ball machine, and their chemistry of films was analyzed with X-ray absorption near-edge spectroscopy (XANES). The results indicate that the two compounds possess excellent anti-wear property and good load-carrying capacity. According to the XANES results, for the thermal films, the outer surfaces are mainly composed of N, S-containing polymer and ferric sulfate, and the near-surface and the bulk are composed of ferrous sulfate, while for the anti-wear films, the outer surfaces are only composed of ferric sulfate, but the near-surface and the bulk are mainly composed of ferrous sulfate.

关键词：摩擦学薄膜化学属性衍生物二硫代氨基甲酸酯