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Carbon Energy 2024年第3期6卷 118-131页

作者： Jia-Ni Lu Yunze Huang Yuan-Sheng Xia Long-Zhang Dong Lei Zhang Jing-Jing Liu lan-gui xie Jiang Liu Ya-Qian lan Jiangsu Key Laboratory of New Power Batteries School of Chemistry and Materials ScienceJiangsu Collaborative Innovation Centre of Biomedical Functional MaterialsNanjing Normal UniversityNanjingChina School of Chemistry South China Normal UniversityGuangzhouChina

The semi-hydrogenation of alkyne to form Z-olefins with high conversion and high selectivity is still a huge challenge in the chemical ***,flammable and explosive hydrogen as the common hydrogen source of this reaction increases the cost and danger of industrial ***,we connect the photocatalytic hydrogen evolution reaction and the semihydrogenation reaction of alkynes in series and successfully realize the high selective production of Z-alkenes using low-cost,safe,and green water as the proton *** the cascade reaction,a series of isomorphic metal–organic cage catalysts(Co_(x)Zn_(8−x)L_(6),x=0,3,4,5,and 8)are designed and synthesized to improve the yield of the photocatalytic hydrogen *** them,Co_(5)Zn_(3)L_(6) shows the highest photocatalytic activity,with a H_(2) generation rate of 8.81 mmol g^(−1) h^(−1).Then,Co_(5)Zn_(3)L_(6) is further applied in the above tandem reaction to efficiently reduce alkynes to Z-alkenes under ambient conditions,which can reach high conversion of>98%and high selectivity of>99%,and maintain original catalytic activity after multiple ***“one-pot”tandem reaction can achieve a highly selective and safe stepwise conversion from water into hydrogen into Z-olefins under mild reaction conditions.

关键词： alkyne semi-hydrogenation hydrogen evolution reaction metal-organic cages photocatalysis Z-olefins

Dehydrative Beckmann rearrangement and the following cascade reactions

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Chinese Chemical Letters 2022年第5期33卷 2407-2410页

作者： Yongjiao Wei Yinghui Liu lan-gui xie School of Chemistry and Materials Science Jiangsu Collaborative Innovation Center of Biomedical Functional MaterialsNanjing Normal UniversityNanjing 210023China College of Life Sciences Nanjing Normal UniversityNanjing 210023China

The Beckmann rearrangement has been predominantly studied for the synthesis of amide and *** strategically using the in situ generated Appel’s salt or Mitsunobu’s zwitterionic adduct as the de-hydrating agent,a series of Beckmann rearrangement and following cascade reactions have been devel-oped *** protocol allows the conversion of various ketoximes into amide,thioamide,tetrazole and imide products in modular *** generality and tolerance of functionalities of this method have been demonstrated.

关键词： Beckmann rearrangement Multiple components reaction Amide Thioamide Tetrazole

Facile methylthiomethylation of the carboxylic acid with bromodimethylsulfonium bromide

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Green Synthesis and Catalysis 2022年第3期3卷 278-281页

作者： Bo Dong Yunze Huang Xing Zhang Jian Shen lan-gui xie National and Local Joint Engineering Research Center of Biomedical Functional Materials School of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Engineering Research Center of Interfacial Chemistry Nanjing UniversityNanjing 210023China School of Food Science and Pharmaceutical Engineering Nanjing Normal UniversityNanjing 210023China

Herein,a mild and simple method to synthesize methylthiomethyl(MTM)esters with commercially available bromodimethylsulfonium bromide is *** developed procedure allows the methylthiomethylation of a vast scope of carboxylic acids,including alkyl,(hetero)aryl and unsaturated acids,with the tolerance of various *** drug or bioactive molecules and amino acids have been successfully converted to their MTM ester analogues as well.

关键词： Methylthiomethylation Bromodimethylsulfonium bromide Carboxylic acid

Effect of Ti and Ta content on the oxidation resistance of Co-Ni-based superalloys

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 351-361页

作者： Yuheng Zhang Zixin Li Yunwei gui Huadong Fu Jianxin xie Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China Key Laboratory for Advanced Materials Processing(MOE) University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China

Co-Ni-based superalloys are known for their capability to function at elevated temperatures and superior hot corrosion and thermal fatigue ***,these alloys show potential as crucial high-temperature structural materials for aeroengine and gas turbine hot-end *** previous work elucidated the influence of Ti and Ta on the high-temperature mechanical properties of ***,the intricate interaction among elements considerably affects the oxidation resistance of *** this paper,Co-35Ni-10Al-2W-5Cr-2Mo-1Nb-xTi-(5−x)Ta alloys(x=1,2,3,4)with varying Ti and Ta contents were designed and compounded,and their oxidation resistance was investigated at the temperature range from 800 to 1000℃.After oxidation at three test conditions,namely,800℃for 200 h,900℃for 200 h,and 1000℃for 50 h,the main structure of the oxide layer of the alloy consisted of spinel,Cr_(2)O_(3),and Al_(2)O_(3)from outside to *** consisting of Ta,W,and Mo formed below the Cr_(2)O_(3)*** interaction of Ti and Ta imparted the highest oxidation resistance to 3Ti2Ta ***,an excessive amount of Ti or Ta resulted in an adverse effect on the oxidation resistance of the *** study reports the volatilization of W and Mo oxides during the oxidation process of Co-Ni-based cast superalloys with a high Al content for the first time and explains the formation mechanism of holes in the oxide *** results provide a basis for gaining insights into the effects of the interaction of alloying elements on the oxidation resistance of the alloys they form.

关键词： Co-Ni-based superalloys high-temperature oxidation Ti and Ta elements formation mechanism of holes

Recent Advances in Asymmetric Structural Composites for Excellent Electromagnetic Interference Shielding: A Review

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Chinese Journal of Polymer Science 2024年第6期42卷 693-710页

作者： Ying Zhou Bai Xue lan xie Chang-Mei Wu Qiang Zheng Department of Polymer Materials and Engineering College of Materials and Metallurgy Guizhou University National Engineering Research Center for Compounding and Modification of Polymer Materials National and Local Joint Engineering Research Center for Functional Polymer Membrane Materials and Membrane Processes State Key Laboratory of Public Big Data Guizhou University Department of Polymer Science and Engineering Zhejiang University

Since electromagnetic pollution is detrimental to human health and the environment, numerous efforts have been successively made to achieve excellent electromagnetic interference shielding effectiveness(EMI SE) via designing the hierarchical structures for electromagnetic interference(EMI) shielding polymer composites. Among the plentiful structures, the asymmetric structures are currently a hot spot, principally categorizing into multi-layered, porous, fibrous, and segregated asymmetric structures, which endows the high EMI shielding performance for polymer composites incorporated with magnetic, conductive, and/or dielectric micro/nano-fillers, due to the “absorption-reflection-reabsorption” shielding mechanism. Therefore, this review provides the retrospection and summary of the efforts with respect to abundant asymmetric structures and multifunctional micro/nano-fillers for enhancing EMI shielding properties, which is conducive to the booming development of polymeric EMI shielding materials for the promising prospect in modern electronics and 5-generation(5G) technology.

关键词： Asymmetric structure Microano functional filler Polymer composite Electromagnetic interference shielding

Experimental and numerical flutter analysis of a folding fin with multiple asymmetric free-plays

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Chinese Journal of Aeronautics 2024年第5期37卷 332-348页

作者： Chenyu LIU Chao AN Changchuan xie Xin ZHANG lan YANG School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Beijing Institute of Electronic System Engineering Beijing 100854China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

Experimental folding fin models with an adjustable free-play are tested in a wind *** fin structure is modeled using the free-interface component mode synthesis method,and its free-play is modeled as four independent nonlinear springs with asymmetric stiffness.A nonplanar unsteady vortex-lattice method considering compressibility is employed to address nonlinear deformation and high subsonic *** spline interpolation is improved through projection and *** aeroelastic characteristics of folding fins with different free-play magnitudes,initial conditions and elastic-axis positions are analyzed using an established time-marching method because of its relatively small computation scale and high *** results show good consistency among the presented method,the wind tunnel test and the harmonic balance *** is a negative correlation between the critical speed of divergent motion and the ratio of the initial condition to the free-play *** either the free-play magnitude or the initial condition is extreme(tiny or vast),the system nonlinearity degenerates to ***,the flutter prevention design of a linear model can be applied to a nonlinear model,such as moving the elastic-axis position *** presented fin configuration exhibits an unstable limit cycle oscillation because the orders of coupled flutter modes do not change with variations in equivalent linear stiffness.

关键词： Free-play Limit cycle oscillation Flutter Component mode synthesis Vortex-lattice method

Synthesis of Planar-Chiral[2.2]Paracyclophane-Based Oxazole-Pyrimidine Ligands and Application in Nickel-Catalyzed 1,2-Reduction ofα,β-Unsaturated Ketones

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Chinese Journal of Chemistry 2024年第7期42卷 705-710页

作者： Juan Wang Qing-Xian xie Xiang Li Chang-Bin Yu Yong-gui Zhou School of Chemistry Dalian University of Technology2 Linggong RoadDalianLiaoning 116024China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China

The planar-chiral ligands have been widely applied as a class of unique and significant ligands in asymmetric *** them,chiral[2.2]paracycyclophane has emerged as a privileged type of planar-chiral framework and has been utilized as an important toolbox due to their structural ***,we design and synthesize[2.2]paracyclophane-derived oxazole-pyrimidine ligands(abberviated as PYMCOX).These N,N-ligands with stable properties,rigid structure and large steric hindrance performed successfully in nickel-catalyzed asymmetric 1,2-reduction ofα,β-unsaturated ketones,affording the chiral allylic alcohols with up to 99%yield and 99%***,this reduction reaction could be conducted on gram-scale without loss of activity and enantioselectivity,and the chiral ligand could be conveniently recovered with high yield.

关键词： Oxazole-pyrimidine ligands Planar chirality Nickel Hydroboration Asymmetric synthesis

Investigating the effect of volatility on the hygroscopicities of acetate nanoparticle aerosols by surface plasmon resonance microscopy

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Journal of Environmental Sciences 2024年第4期138卷 167-178页

作者： Bo Yang Zhibo xie Jianguo Liu Huaqiao gui Jiaoshi Zhang Xiuli Wei Zetao Fan Douguo Zhang Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China CAS Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Advanced Laser Technology Laboratory of Anhui Province Department of Optics and Optical EngineeringUniversity of Science and Technology of ChinaHefei 230026China

Under high relative humidity(RH)conditions,the release of volatile components(such as acetate)has a significant impact on the aerosol *** this work,one surface plasmon resonance microscopy(SPRM)measurement system was introduced to determine the hygroscopic growth factors(GFs)of three acetate aerosols separately or mixed with glucose at different *** Ca(CH_(3)COO)_(2) or Mg(CH_(3)COO)_(2) aerosols,the hygroscopic growth trend of each time was lower than that of the previous time in three cyclic humidification from 70% RH to 90% RH,which may be due to the volatility of acetic acid leading to the formation of insoluble hydroxide(Ca(OH)_(2) or Mg(OH)_(2))under high RH *** the third calculated GF(using the Zdanovskii-Stokes-Robinson method)for Ca(CH_(3)COO)_(2) or Mg(CH_(3)COO)_(2) in bicomponent aerosols with 1:1 mass ratio were 3.20% or 5.33% lower than that of the first calculated GF at 90% *** calculated results also showed that the hygroscopicity change of bicomponent aerosol was negatively correlated with glucose content,especially when the mass ratio of Mg(CH_(3)COO)_(2) to glucose was 1:2,the GF at 90% RH only decreased by4.67% after three cyclic *** coupled plasma atomic emission spectrum(ICP-AES)based measurements also indicated that the changes of Mg^(2+)concentration in bicomponent was lower than that of the *** results of this study reveal thatduring the efflorescence transitions of atmospheric nanoparticles,the organic acids diffusion rate may be inhibited by the coating effect of neutral organic components,and the particles aging cycle will be prolonged.

关键词： Hygroscopic growth Volatility Acetate aerosols Nanoparticle aerosol Surface plasmon resonance

An effective'salt in dimethyl sulfoxide/water'electrolyte enables high-voltage supercapacitor operated at-50℃

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Journal of Energy Chemistry 2024年第6期93卷 361-367,I0009页

作者： Yingbin Liu Chang Yu Xuedan Song Siyi Hou Shuqin lan Jinhe Yu Yuanyang xie Jieshan Qiu State Key Lab of Fine Chemicals Frontier Science Center for Smart MaterialsSchool of Chemical EngineeringLiaoning Key Lab for Energy Materials and Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina School of Chemistry Frontier Science Center for Smart MaterialsLiaoning Key Lab for Energy Materials and Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina College of Chemical Engineering State Key Laboratory of Chemical Resource EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Compared with organic electrolytes,aqueous electrolytes exhibit significantly higher ionic conductivity and possess inherent safety features,showcasing unique advantages in ***,challenges remain for low-salt aqueous electrolytes operating at high voltage and low ***,we report a low-salt(0.87 m,m means mol kg^(-1))'salt in dimethyl sulfoxide/water'hybrid electrolyte with non-flammability via hybridizing aqueous electrolyte with an organic co-solvent of dimethyl sulfoxide(hydrogen bond acceptor).As a result,the 0.87 m hybrid electrolyte exhibits enhanced electrochemical stability,a freezing temperature below-50℃,and an outstanding ionic conductivity of 0.52mS cm~(-1)at-50℃.Dimethyl sulfoxide can anchor water molecules through intermolecular hydrogen bond interaction,effectively reinforcing the stability of water in the hybrid ***,the interaction between dimethyl sulfoxide and water molecules diminishes the involvement of water in the generation of ordered ice crystals,finally facilitating the low-temperature performance of the hybrid *** paired with the 0.87 m'salt in dimethyl sulfoxide/water'hybrid electrolyte,the symmetric supercapacitor presents a 2.0 V high operating voltage at 25℃,and can operate stably at-50℃.Importantly,the suppressed electrochemical reaction of water at-50℃further leads to the symmetric supercapacitor operated at a higher voltage of 2.6 *** modification strategy opens an effective avenue to develop low-salt electrolytes for high-voltage and low-temperature aqueous supercapacitors.

关键词： Dimethyl sulfoxide Co-solvent High voltage Low temperature Supercapacitors

Bioinspired Hemostatic Strategy via Pulse Ejections for Severe Bleeding Wounds

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Research 2024年第1期2023卷 281-299页

作者： Bitao Lu Enling Hu Weiwei Ding Wenyi Wang Ruiqi xie Kun Yu Fei Lu Guangqian lan Fangyin Dai State Key Laboratory of Silkworm Genome Biology College of SericultureTextile and Biomass SciencesSouthwest UniversityChongqing 400715China Chongqing Engineering Research Center of Biomaterial Fiber and Modern Textile Chongqing 400715China Division of Trauma and Surgical Intensive Care Unit Research Institute of General SurgeryJinling HospitalMedical School of Nanjing UniversityNanjing210002 Jiangsu ProvinceChina Department of Applied Biology and Chemical Technology The Hong Kong Polytechnic UniversityHong KongChina

Efficient hemostasis during emergency trauma with massive bleeding remains a critical challenge in prehospital ***,multiple hemostatic strategies are critical for treating large bleeding *** this study,inspired by bombardier beetles to eject toxic spray for defense,a shape-memory aerogel with an aligned microchannel structure was proposed,employing thrombin-carrying microparticles loaded as a built-in engine to generate pulse ejections for enhanced drug *** aerogels,after contact with blood,can rapidly expand inside the wound,offering robust physical barrier blocking,sealing the bleeding wound,and generating a spontaneous local chemical reaction causing an explosivelike generation of CO_(2) microbubbles,which provide propulsion thrust to accelerate burst ejection from arrays of microchannels for deeper and faster drug *** ejection behavior,drug release kinetics,and permeation capacity were evaluated using a theoretical model and experimentally *** novel aerogel showed remarkable hemostatic performance in severely bleeding wounds in a swine model and demonstrated good degradability and biocompatibility,displaying great potential for clinical application in humans.

关键词： wound sealing offering