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Chinese Journal of Chemistry 2016年第5期34卷 490-494页

作者： Taotao Li Peng Yu jin-shun lin Yonggang Zhi Xin-Yuan Liu Chengdu Institute of Organic Chemistry Chinese Academy ofSeienees Chengdu Sichuan 610041 China Department of Chemistry South University of Science and Technology of China Shenzhen Guang dong 518055 China

A Cu-catalyzed remote sp3 C--H/unactivated alkenes functionalization reaction for the concomitant construc- tion of C--CF3 and C--O bonds was described. An 1,5-H radical transfer involving an sp3 C--H bond adjacent to a nitrogen atom and an a-CF3-alkyl radical intermediate derived from unactivated alkenes was observed and demon- strated to proceed via the radical process.

关键词： alkenes radical trifluoromethylation 1,5-H radical transfer Togni's reagent

Chiral N-triflylphosphoramide-catalyzed asymmetric hydroamination of unactivated alkenes: a hetero-ene reaction mechanism

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Organic Chemistry Frontiers 2022年第6期9卷 1649-1661页

作者： Na Wang Li-Wen Fan jin Zhang Qiang-Shuai Gu jin-shun lin Guo-Qiang Chen Xin-Yuan Liu Peiyuan Yu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518071China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Department of Chemistry and Shenzhen Grubbs Institute Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055China Academy for Advanced Interdisciplinary Studies and Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China

A highly enantioselective intramolecular hydroamination reaction catalyzed by chiralN-triflylphosphoramide (NTPA) that features an exceptionally broad substrate scope of isolated unactivated alkenes was recently reported by some of us. Herein we report a detailed density functional theory(DFT) study that unveil an uncommon hetero-ene reaction mechanism for this transformation. The reaction changes from a stepwise mechanism involving discrete tertiary carbocation formation to a concertedmechanism to avoid the generation of energetically unfavorable secondary carbocation species for distinctly substituted alkene substrates. The reactivity of this reaction is primarily affected by the substituentson the internal carbon of the alkene, with the carbocation-stabilizing ones promoting the reaction. Inaddition, the reaction is also influenced by the substituents on the terminal alkene carbons: those diminishing the innate alkene polarization of the starting alkenes retard the reaction by disfavoring the formation of related transition states featuring highly polarized alkene residues. The steric effect of all thesealkene substituents was found to be largely unimportant due to the unique arrangement of the heteroene reaction complex that keeps the reacting alkene away from the sterically congested core region ofthe catalyst pocket. The lower acidity of chiral phosphoric acids than that of chiral NTPAs renders the protonated precomplex along the hetero-ene reaction pathway greatly thermodynamically disfavored. Thisindirectly results in a greater relative distortion in the corresponding transition state, which in turn causesreaction retardation. Our results demonstrate the use of intramolecular pericyclic reactions as an alternative strategy for alkene activation by chiral Brønsted acid catalysis and provide insights into the furtherdevelopment of asymmetric hydrofunctionalization of unactivated alkenes.

关键词： mechanism substituent asymmetric

Radical trifluoromethylation-triggered unactivated alkene and remote C-H bond functionalization

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Radical trifluoromethylation-triggered unactivated alkene an...

CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

中国化学会全国第十一届有机合成化学学术研讨会

作者： Peng Yu jin-shun lin Lei Li 谭斌刘心元南方科技大学

Enantiopure trifluoromethyl(CF)-containing molecules have been widely applied in syntheses of a large number of ***,the development of versatile,catalytic and enantioselective methodologies through the concurrent activation of simple alkene and C-H bond for the synthesis of enantiopure CF-containing compounds remains a significant *** address this demand and as part of our continued interest in the area of trifluoromethylation and asymmetric catalysis, we herein report a Cu-catalysed unactivated alkene/remote C-H bond difunctionalization reaction for the concomitant construction of C-CF and C-0 bonds towards N.O-aminals with high ***,an asymmetric version of this reaction was also realized by using a Cu/Bronsted acid cooperative catalytic system,providing facile access to valuable chiral CF-containing N,O-aminals with excellent enantioselectivity.

关键词： Trifluoromethylation C-H functionalization Cooperative catalysis Enantioselective N,O-aminals

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Journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： jin-Peng Wang Guo-Cui Mao Hui-lin Jiang Bao-Xia Dong Yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： CO 2 methanation Metal hydride Ni catalysts Carbonate Metal-carbonate interface

Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期7卷 152-160页

作者： Zhi-Jun Xie Jia-lin Li ling Gong Xiang-Li Zhong Hong-Jia Song jin-Bin Wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance

基于GPRS网络的环境自动监控数据传输系统的设计

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江苏环境科技 2004年第3期17卷 11-12页

作者：王经顺张璘江苏省环境监测中心江苏南京210036

分析了江苏省环境自动监控系统数据传输的现状,提出了一种基于GPRS网络的环境自动监控数据传输系统,并进行了详细的设计。

关键词： GPRS网络环境监测系统自动监控数据传输系统中心监控层

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Negative PO3-implanted bionic ion transport channels for promoting Li-S battery

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Science China Chemistry 2025年

作者： Wenhuan Huang shun Wang Xuehan Hou Yanan Zhang Xingxing Zhang Yaoxiao Zhao Xilang jin Huabin Zhang Fei Wang Jian Zhang Key Laboratory of Chemical Additives for China National Light Industry College of Chemistry and Chemical EngineeringShaanxi University of Science and Technology School of Materials and Chemical Engineering Xi'an Technological University Chemistry Program Physical Science and Engineering Division King Abdullah University of Science and Technology State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Lithium-sulfur （Li-S） battery,as a promising next-generation high-energy-density battery,suffers from lithium polysulfides（LPSs） shuttle and Li dendrites *** crystalline framework-based membranes as separator can effectively absorb and restrain LPSs but without precise structural design principal exploration and mechanism ***,bio-inspired 1D oriented lithium-ion transport channels with molecular negatively charged PO3（-1） have been developed in hybrid tetrazole frameworks for promoting the transmission of Li+*** theoretical calculations and in situ spectroscopy demonstrated the higher binding energy and inhibited diffusion of LPSs in *** assembled PP@PO3Janus separator in Li-S coin cell delivered a high initial capacity of 1410.9 mAh g-1at 0.1 C and a low attenuation rate of 0.038%per cycle over 500 cycles at 5 ***,the high capacities of 862,542 and 409 mAh g-1based on high-sulfur-loading cathodes of 2.6,3.8 and 5.0 mg cm-2at0.5 C were achieved,***,the punch battery of PO3@PP separator with S-cathode of 1.2 mg cm-2has been developed for demonstrating its potentials commercial application,which displays impressive capacity of 873.4 mAh g-1with the retention of～78.9%over 50 cycles.

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模糊控制在家电产品中的应用与展望

五邑大学学报（自然科学版） 2001年第2期15卷 18-23页

作者：肖健华经顺林五邑大学智能技术与系统研究所广东江门529020 金羚企业集团公司广东江门529040

介绍了模糊控制技术在全自动洗衣机、空调、冰箱等家用电器中的应用，并结合最新的技术手段，讨论了智能家电的发展趋势.

关键词：模糊控制单片机神经网络家用电器智能家电

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Mechanical properties and microstructures of Mg-6Si alloys fabricated using the tungsten-inert-gas arc additive manufacturing

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China Foundry 2025年

作者： Peng-cheng Zhou Guo-qiang You jin-yu Feng Lei Wang Xiao lin Bin Jiang College of Materials Science and Engineering Chongqing University National Engineering Research Center for Magnesium Alloys Chongqing University National Key Laboratory of Advanced Casting Technologies Chongqing University

Si-containing Mg alloys solidified at conventional rates often contain coarse and sharp Mg2Si phases,which can result in inferior material *** this study,Mg-6wt.%Si （Mg-6Si） alloy was prepared by wire arc additive manufacturing （WAAM）,employing the gas tungsten arc welding technique with rapid *** microstructures and mechanical properties of the WAAM alloy were investigated and compared with those of the as-cast samples produced using a metal *** results indicate that the WAAM Mg-6Si is harder and stronger than the as-cast *** microhardness of the WAAM Mg-6Si increases by 36.6%in comparison to that of as-cast Mg-6Si ***,the average tensile strengths at room temperature and 150°C increases by 63.4%and 21.3%,*** refines both the Mg2Si phase and the overall grains,resulting in a homogeneous morphology and improved mechanical *** granular Mg2Si phase,characterized by fine particles with a diffused distribution,shows a significant increase in *** acicular Mg2Si phase is distributed along the grain boundaries,and its concentration significantly *** average grain size of the Mg2Si phase is about 9.20μm,about 5 times *** refinement and distribution of the granular Mg2Si phase,as well as the reduction in the amount of needle-like Mg2Si particles,are the key factors for improving the mechanical properties of WAAM Mg-6Si alloy.

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Metastable seed-crystals: epitaxial growth of branched-array organic heterostructure nanowires

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Science China Chemistry 2025年

作者： jin Feng Zhen-Yu Geng Ting-Yao Song Ying-Xin Ma Chuan-Zeng Wang Wei Zhang Hong-Tao lin jin Zhou Shu-Ping Zhuo Shu-Hai Chen Xue-Dong Wang School of Chemistry and Chemical Engineering Shandong University of Technology Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & DevicesSoochow University College of Chemistry and Chemical Engineering Hunan Normal University

Tunable light–matter interactions are exhibited by organic low-dimensional crystals, making these crystals a promising platform for organic photonics. However, the precise synthesis of organic low-dimensional crystals remains challenging due to the stochastic nature of molecular nucleation processes. Herein, the directed nucleation process is driven by the introduction of metastable seed-crystals as the trunk, which ultimately leads to branched-array organic heterostructures. The successful formation of organic heterostructures with high-density branched arrays is attributed to the highest attachment energy (Eatt（023）=-104.25 kcal mol-1) of the exposed （023） crystal plane during the seed-crystal growth route. Significantly, these as-prepared heterostructures inherently have an ultralow lattice mismatch ratio η of 0.7%between trunk and branch, which contributes to the multi-channel photon transportation. Therefore, this work provides valuable insights into a versatile synthetic strategy for accessing low-dimensional heterostructures for integrated optoelectronics.

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