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Chinese Journal of Chemistry 2024年第22期42卷 2723-2727页

作者： Yue Li dian-feng chen Hefei National Research Centerfor Physical Sciences at the Microscale and Department of Polymer Science and Engineering University of ScienceandTechnologyof ChinaHefeiAnhui 230026China

Comprehensive Summary Discovery of unprecedented donor-acceptor patterns can essentially enrich the chemistry of donor-acceptor *** herein introduce a concept of vinylogous fluorine stabilizing effect,which guides rational design of a novel donor-acceptor cyclopropane employing gem-difluorovinyl group as the electron donor,namely *** of such dFVCPs in a[3+2]cycloaddition with aldehydes and a controlled ring-opening polymerization by a Mg(OTf)2/DIPEA/C(sp3)-H initiator system have been demonstrated,providing direct access to fluorine-containing tetrahydrofurans and all-carbon main-chain polymers.

关键词： Donor-acceptor cyclopropane gem-Difluorovinyl group Vinylogous fluorine stabilizing effect [3+2]cycloaddition Ring-opening polymerization Strainedmolecules Monomers lonic polymerization

Recent progress in organocatalytic asymmetric total syntheses of complex indole alkaloids

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National Science Review 2017年第3期4卷 381-396页

作者： Jin Song dian-feng chen Liu-Zhu Gong Hefei National Laboratory for Physical Sciences at the Microscale and Department of ChemistryUniversity of Science and Technology of China Collaborative Innovation Center of Chemical Science and Engineering

Indole and its structural analogues have been frequently found in numerous alkaloids, pharmaceutical products and related materials. The enantioselective construction of these structures allows efficient total synthesis of optically pure indole alkaloids, and hence has received worldwide interest. In the past decade,asymmetric organocatalysis has been recognized as one of the most powerful strategies to create chiral molecules with high levels of stereoselectivity. In particular, organocatalytic asymmetric cascade reactions often occur with multiple bond-breaking and forming events simultaneously or sequentially, leading to the appearance of various straightforward approaches to access core structures for asymmetric total *** review will summarize recent applications of asymmetric organocatalysis in the enantioselective synthesis of indole alkaloids.

关键词： asymmetric catalysis organocatalysis indole alkaloids total synthesis

Effect of milling duration on hydrogen storage thermodynamics and kinetics of ball-milled Ce-Mg-Ni-based alloy powders

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Journal of Iron and Steel Research International 2018年第7期25卷 746-754页

作者： dian-chen feng Hao Sun Xi-tao Wang Yang-huan Zhang School of Materials and Metallurgy Inner Mongolia University of Science and Technology Baotou 014010 Inner Mongolia China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China Department of Functional Material Research Central Iron and Steel Research Institute Beijing 100081 China

To improve the hydrogen storage performance of CeMg12-type alloys, partially substituting Mg with Ni in the alloy was conducted. The way to synthesize the target alloy powders was the mechanical milling method, by which the CeMg11-Ni ＋ x wt% Ni （x = 100, 200） alloy powders with nanocrystalline and amorphous structure were obtained. The influence of the milling time and Ni content on the hydrogen storage properties of the alloys was discussed. The X-ray diffractometer and high-resolution transmission electron microscope were used to investigate the microstructures of the ball-milled alloys. The hydrogenation/dehydrogenation dynamics were studied using a Sievert instrument and a differential scanning calorimeter which was linked with a H2 detector. The hydrogen desorption activation energies of the alloy hydrides were evaluated by Arrhenius and Kissinger equations. From the results point of views, there is a little decline in the thermo- dynamic parameters （enthalpy and entropy changes） with the increase in Ni content. However, the alloys desorption and absorption dynamics are improved distinctly. What is more, the variation of milling time results in a dramatic influence on the hydrogen storage performances of alloys. Various maximum values of the hydrogen capacities correspond to different milling time, which are 5.805 and 6.016 wt% for the CeMgllNi ＋ x wt% Ni （x = 100, 200） alloys, respectively. The kinetics tests suggest that the hydrogen absorption rates increase firstly and then decrease with prolonging the milling time. The improvement of the gaseous hydrogen storage kinetics results from the decrease in the activation energy caused by the increase in Ni content and milling time.

关键词： CeMg12 alloy Mechanical milling Amorphous - Activation energy Hydrogen storage kinetics Thermodynamics

Access to chiral homoallylic vicinal diols from carbonyl allylation of aldehydes with allyl ethers via palladium-catalyzed allylic C-H borylation

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Science China Chemistry 2022年第2期65卷 298-303页

作者： Tian-Ci Wang Pu-Sheng Wang dian-feng chen Liu-Zhu Gong Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of ChinaHefei 230026China Center for Excellence in Molecular Synthesis of CAS Hefei 230026China

Chiral homoallylic vicinal diols are found in many bioactive compounds and are among the most versatile functional groups in organic chemistry. Here, we describe an asymmetric carbonyl allylation of aldehydes with allyl ethers proceeding via allylic C-H borylation enabled by palladium and chiral phosphoric acid sequential catalysis, providing facile access to homoallylic vicinal anti-diols in high yields and with excellent stereoselectivity. This protocol enables the total synthesis of aigialomycin D to be finished within 7 steps.

关键词： asymmetric catalysis palladium allylic C–H borylation allyl ethers chiral phosphoric acid aldehydes

Influence of melt spinning and annealing treatment on structures and hydrogen storage thermodynamic properties of La0.8Pr0.2MgNi3.6Co0.4 alloy

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Journal of Iron and Steel Research International 2020年第1期27卷 114-120页

作者： Ting-ting Zhai Ze-ming Yuan feng Hu Long Luo Yong-zhi Li Hao Sun dian-chen feng Yang-huan Zhang School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China

La0.8Pr0.2MgNi3.6Co0.4 alloys were prepared by induction melting,annealing and melt spinning *** influences of annealing treatment and melt spinning on phase structure and hydrogen storage properties were systematically *** results of X-ray diffraction determine that the as-cast and as-spun La0.8Pr0.2MgNi3.6Co0.4 alloys consist of LaMgNi4 and LaNi5 phases,while only LaMgNi4 phase is present in the as-annealed *** scanning electron microscope images illustrate that the grain of the alloy is significantly refined by melt spin ning tech no *** gaseous hydrogen storage kinetic and thermodynamic properties were measured by using a Sievert's apparatus at different *** maximum hydrogen storage capacity of the as-cast,as?spun and as-annealed La0.8Pr0.2MgNi3.6Co0.4 alloy is 1.699,1.637 and 1.535 wt.% at 373 K and 3 MPa,*** annealed alloy has flatter and wider pressure plateaus compared with the as-cast and as-spun alloys,which correspond to the hydrogen absorption and desorption process of LaMgNi4 and corresponding ***,the enthalpy and entropy changes of LaMgNi4 during hydrogenation at different temperatures were calculated using Van't Hoff methods.

关键词： Hydrogen storage Multiphase structure Annealing Melt spinning Thermodynamics

Highly ameliorated gaseous and electrochemical hydrogen storage dynamics of nanocrystalline and amorphous LaMg_(12)-type alloys prepared by mechanical milling

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Journal of Iron and Steel Research International 2017年第1期24卷 50-58页

作者： dian-chen feng Hao Sun Zhong-hui Hou Dong-liang Zhao Xi-tao Wang Yang-huan Zhang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing School of Materials and Metallurgy Inner Mongolia University of Science and Technology Department of Functional Material Research Central Iron and Steel Research Institute

Nanocrystalline and amorphous LaMg12-type alloy-Ni composites with a nominal composition of LaMg11Ni＋x wt.% Ni（x=100,200）were synthesized via ball *** influences of ball milling duration and Ni adding amount xon the gaseous and electrochemical hydrogen storage dynamics of the alloys were systematically *** hydrogen storage performances were studied by a differential scanning calorimeter and a Sievert *** dehydrogenation activation energy of the alloy hydrides was evaluated by Kissinger *** electrochemical hydrogen storage dynamics of the alloys was investigated by an automatic galvanostatic *** H atom diffusion and apparent activation enthalpy of the alloys were *** results demonstrate that a variation in Ni content remarkably enhances the gaseous and electrochemical hydrogen storage dynamics performance of the *** gaseous hydriding rate and high-rate discharge（HRD）ability of the alloys exhibit maximum values with varying milling ***,the dehydriding kinetics of the alloys is always accelerated by prolonging milling ***,rising milling time from 5to 60 h makes the hydrogen desorption ratio（a ratio of the dehydrogenation amount in 20 min to the saturated hydrogenation amount）increase from 57%to 66%for x=100alloy and from 57%to 70%for x=***,the improvement of gaseous hydrogen storage kinetics is attributed to the descending of dehydrogenation activation energy caused by the prolonging of milling duration and growing of Ni content.

关键词： Mechanical milling Hydrogen storage Electrochemical performance Kinetics Activation energy

Hydrogen storage thermodynamics and dynamics of La-Mg-Ni-based LaMg12-type alloys synthesized by mechanical milling

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Rare Metals 2019年第12期38卷 1144-1152页

作者： Yang-Huan Zhang Peng-Fei Gong Long-Wen Li Hao Sun dian-chen feng Shi-Hai Guo Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010China Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China

Nanocrystalline/amorphous LaMg(12)-type alloyNi composites with a nominal composition of LaMg(11)Ni+x wt% Ni(x=100,200) were synthesized by mechanical *** of Ni content and milling time on the gaseous hydrogen storage thermodynamics and dynamics of alloys were systematically *** hydrogen desorption properties were studied by Sievert apparatus and a differential scanning calorimeter(DSC).Thermodynamic parameters(△H and ΔS) for the hydrogen absorption and desorption of alloys were calculated by Van't Hoff *** desorption activation energy of alloy hydride was estimated by Arrhenius and Kissinger *** increase in Ni content has a slight effect on the thermodynamic properties of alloys,but it significantly enhances the hydrogen absorption and desorption kinetics performance of ***,variation of milling time clearly affects the hydrogen storage properties of *** absorption capacity(C(100)~a) and hydrogen absorption saturation ratio(R(10)~a)(a ratio of the hydrogen absorption capacity at 10 min to the saturated hydrogen absorption capacity) have maximum values with milling time *** hydrogen desorption ratio(R(20)~d)(a ratio of the hydrogen desorption capacity at 20 min to the saturated hydrogen absorption capacity) always increases with milling time ***,prolonging milling time from 5 to 60 h makes R(20)~d increase from 10.89% to 16.36% for the x=100 alloy and from 13.93% to 21.68% for the x=200 alloy,respectively.

关键词： LaMg(12)alloy Mechanical milling Thermodynamics and dynamics Activation energy Hydrogen storage

Asymmetric Metal/Bifunctional Squaramide Relay Catalysis

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Asymmetric Metal/Bifunctional Squaramide Relay Catalysis

Hydrogen storage behavior of nanocrystalline and amorphous La-Mg-Ni-based LaMg_(12)-type alloys synthesized by mechanical milling

手性中国2014学术研讨会

作者： dian-feng chen Pei-Yu Wu feng Zhao Liu-Zhu Gong Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of China Collaborative innovation Center of Chemical Science and Engineering(Tianjin)

＜正＞Superior qualities of both metals and chiral organocatalysts are recently combined in the categories of cooperative catalysis,sequential catalysis and relay catalysis.1 We and other groups have developed a variety of metal/chiral phosphoric acid relay catalysis.2 In contrast,neutral Bronsted acids,especially nitrogen or sulfur contained bifunctional organocatalysts,have not been exploited in metal-involved relay catalysis.

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Transactions of Nonferrous Metals Society of China 2017年第3期27卷 551-561页

作者： Yang-huan ZHANG Long-wen LI dian-chen feng Peng-fei GONG Hong-wei SHANG Shi-hai GUO Key Laboratory of Integrated Exploitation of Baiyun Obo Multi-metal Resources Inner Mongolia University of Science and Technology Baotou 014010 China Department of Functional Material Research Central Iron and Steel Research Institute Beijing 100081 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Nanocrystalline and amorphous LaMg11Ni+x%Ni(x=100,200,mass fraction)alloys were synthesized by *** electrochemical hydrogen storage properties of the as-milled alloys were tested by an automatic galvanostatic *** gaseous hydrogen absorption and desorption properties were investigated by Sievert’s apparatus and differential scanningcalorimeter(DSC)connected with a *** results indicated that increasing Ni content significantly improves the gaseousand electrochemical hydrogen storage performances of the as-milled *** gaseous hydrogen absorption capacities andabsorption rates of the as-milled alloys have the maximum values with the variation of the milling *** the hydrogen desorptionkinetics of the alloys always increases with the extending of milling *** addition,the electrochemical discharge capacity andhigh rate discharge(HRD)ability of the as-milled alloys both increase first and then decrease with milling time prolonging.

关键词： Ni-MH battery hydrogen storage alloy mechanical milling discharge capacity kinetics

Gradient‑Layered MXene/Hollow Lignin Nanospheres Architecture Design for Flexible and Stretchable Supercapacitors

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Nano-Micro Letters 2025年第2期17卷 447-462页

作者： Haonan Zhang cheng Hao Tongtong Fu dian Yu Jane Howe Kaiwen chen Ning Yan Hao Ren Huamin Zhai Jiangsu Provincial Key Lab of Sustainable Pulp and Paper Technology and Biomass Materials NanJing Forestry UniversityNanjing 210037People’s Republic of China Department of Chemical Engineering and Applied Chemistry University of Toronto200 College StreetTorontoON M5S 3E5Canada Department of Materials Science and Engineering University of Toronto184 College StreetTorontoON M5S 3E4Canada College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037People’s Republic of China

With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has *** this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable *** depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene ***,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of *** these strategies effectively enhanced the capacitive performance of the *** addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the *** electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),***,their capacitances were well preserved after 1000 times of 600%stretch-release *** study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.

关键词： Hollow lignin nanospheres MXene Gradient-layered architecture Wrinkled electrodes Stretchable supercapacitors