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Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun Liu Yiren yu Guoshu Gao yumeng Zhao xiongfu Zhang Guodong Liu Guohui Yang State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： Aspect ratio

High-energy-density lithium manganese iron phosphate for lithium-ion batteries: Progresses, challenges, and prospects

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journal of Energy Chemistry 2025年第1期100卷 1-17页

作者： Bokun Zhang xiaoyun Wang Shuai Wang Yan Li Libo Chen Handong jiao Zhijing yu jiguo Tu State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Research Institute for Intelligent Wearable Systems The Hong Kong Polytechnic University Institute of Advanced Structure Technology Beijing Institute of Technology

The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion *** manganese iron phosphate (LiMnxFe1-xPO4) has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy *** LiMnxFe1-xPO4has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and Li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap *** review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of LiMnxFe1-xPO4to analyze reaction processes accurately and guide material ***,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of LiMnxFe1-xPO4,including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology ***,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are *** importantly,it is expected to provide key insights into the development of high-performance and stable LiMnxFe1-xPO4materials,to achieve practical energy storage requirements.

关键词： Semiconductor doping

Guided Waves in the Multilayered One-Dimensional Hexagonal Quasi-crystal Plates

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Acta Mechanica Solida Sinica 2021年第1期34卷 91-103页

作者： B.Zhang j.G.yu x.M.Zhang x.H.Wang School of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo454003China

Guided waves in the multilayered one-dimensional quasi-crystal plates are,respectively,investigated in the context of the Bak and elasto-hydrodynamic *** curves and phonon and phason displacements are calculated using the Legendre polynomial *** characteristics in the context of these two models are analyzed in *** show that the phonon-phason coupling effects on the first two layers are the same at low frequencies;but,they are more significant on the first layer than those on the second layer at high *** obtained results lay the theoretical basis of guided-wave nondestructive test on multilayered quasi-crystal plates.

关键词： Multilayered structures Quasi-crystal plate Guided wave Phonon-phason coupling effect

Deformation kinking and highly localized nanocrystallization in metastableβ-Ti alloys using cold forging

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journal of Materials Science & Technology 2022年第25期120卷 53-64页

作者： Keer Li W.Chen G.x.yu j.Y.Zhang S.W.xin j.x.Liu x.x.Wang j.Sun State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China Northwest Institute for Nonferrous Metal Research Xi’an 710016China Baoji Titanium Industry Co. Ltd.Baoji 721014China

Deformation kinking as an uncommon plastic deformation mechanism has been reported in several materials while the relevant microstructure evolution and grain refinement behavior at a large strain remain unclear so *** this study,the issue was systematically investigated by utilizing cold forging to impose severe plastic deformation(SPD)on Ti-11 V metastableβ-Ti *** is found that the formation of kink bands experiences dislocation gliding,pre-kinking and the ripening of pre-kinks in *** kink bands are subsequently thickened through the coalescence of multiple kink bands in a manner of high *** dislocation slip is developed as a dominant deformation mechanism when deformation kinking is *** resulting grain refinement involves transverse breakdown and longitudinal splitting of dislocation walls and cells,which fragment kink bands into smallβ-*** refinement of theβ-blocks is still governed by dislocation activities,and finally nanograins with a diameter of~15 nm are produced at a large strain of ***,it is revealed that nanocrystallization is highly localized inside kink bands while the outer microstructure maintains original coarse *** localized refinement characterization is ascribed to the intrinsic soft nature of kink bands,shown as low hardness in nanoindentation *** intrinsic softening of kink bands is uncovered to originate from the inner degraded dislocation density evidenced by both experimental measurement and theoretical *** findings enrich fundamental understanding of deformation kinking,and shed some light on exploring the deformation accommodation mechanisms for metal materials at large strains.

关键词： Metastableβ-Ti alloys Deformation kinking Microstructural evolution Grain refinement Dislocations

Wideband high gain millimeter wave antenna based on wavy power divider for millimeter wave radar sensor

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The journal of China Universities of Posts and Telecommunications 2025年

作者： Zhang Shuanggen yu Tao Wang yulan Zhou Ran Cheng Zhihua School of Integrated Circuit Science and Engineering， Tianjin University of Technology

In this paper， a broadband high gain millimeter wave radar array antenna based on a wavy power divider is proposed. The radar antenna comprises a wavy power divider and a 10-element array antenna. By adjusting the wavy radius of the power divider， the surface current of the power divider is altered， resulting in better impedance matching with the antenna. This ultimately leads to a significant improvement in bandwidth performance. The 410 millimeter wave radar antenna loaded with wavy power divider exhibits an approximate enhancement of 3 GHz compared to traditional microstrip power divider antennas， and an average gain increase of 2.42 dB within the vehicle millimeter wave radar frequency band relative to the improved gradient power divider structure. The 410 millimeter wave radar antenna loaded with wavy power divider possesses the characteristics of high gain and broad bandwidth.

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Fabrication of carbon-supported Al2O3 nanoparticles via spontaneous cross-linking to enhance selective hydrogenation of furfural

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journal of Energy Chemistry 2025年第1期100卷 612-620页

作者： Weiwei yu xinbao Zhang Hongyu Chen Yanan Wang Shaoguo Li Fucun Chen Zhenni Liu xiujie Li xiangxue Zhu State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=***,a novel Al2O3/C-u hybrid catalyst,composed of N-modified dendritic carbon networks supporting Al2O3nanoparticles,was successfully prepared via carbonizing the freeze-dried gel from spontaneous cross-linking of alginate,Al3+and *** obtained carbon-supported Al2O3hybrid catalyst has a high ratio （31%） of Al species in pentahedral-coordinated *** introduction of urea enhances the surface N content,the ratio of pyrrolic N,and specific surface area of catalyst,leading to improved adsorption capacity of C=O and the accessibility of active *** the furfural hydrogenation reaction with isopropyl alcohol as hydrogen donor,Al2O3/C-u catalyst achieved a 90%conversion of furfural with 98.0% selectivity to furfuryl alcohol,outperforming that of commercial γ-***,Al2O3/C-u demonstrates excellent catalytic stability in the recycling tests attributed to the synergistic effect of abundant weak Lewis acid sites and the anchoring effect of the carbon network on *** work provides an innovative and facile strategy for fabrication of carbon-supported Al2O3hybrid catalysts with rich AlVspecies,serving as a high selective hydrogenation catalyst through MPV reaction route.

关键词： Selective hydrogenation Furfural Furfuryl alcohol Cross-linking Carbon supported Al 2 O 3 MPV route

CERIUM-INDUCED GRAIN BOUNDARY STRENGTHENINGOF Ni_3Al ALLOYS

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Acta Metallurgica Sinica(English Letters) 1997年第4期10卷 349-357页

作者： Z.x. yuan S.H. Song T.H. x.i x.j. Zhangand Z.S. yu(Department of Material, Wuhan Ye in University of Science and Technology, Wuhan 430081, China)(Department of Materials Physics, University of Science and Technology Beijing, Beijing 100083, China) Wuhan Yejin Univ of Science and Technology Wuhan China

The infiuence of cerium on grnin boundaries of polycrpstalline N3Al alloys has beenstudied. The ja6mcability of a Ce-doped N3Al alloy strongly depends on the certumcontent. The alloy exhibits very poor fabrica6ility and cannot be fabrtcated into goodsheet8 by cold rolling when the concentmtion of cerium is 0.044wt%.A 0.011wt%Ce-doped N3Al alloy exhibits relatively good fabricability and may be fab-ricated into useful sheets by repeated cold rolling with 1OOa C annealing. The ductilityof the alloy strongly depends on the cerium distribution. Wthout the grain boundaryprecipitation of a second phase containing cer1um) the higher the segmpation level ofcerzum, the 6ettcr the tensile properties of the alloys, and in turn the more enhancedthe grain boundary cohesion.

关键词： segregation Ni_3Al alloy ductility fabrication cerium

Systematic Acupuncture Explains Acupuncture at Baihui(GV20) and Fengchi(GB20) Targeting the Inflammatory Response to Regulate Migraine

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journal of Traditional Chinese Medicine 2025年

作者： MIN yu ZHENG Meifeng SUN ju PENG Zetong CAO Zhixian HUANG xiaohua Medical College of Acu-Moxi and Rehabilitation， Guangzhou University of Chinese Medicine Department of Rehabilitation Medicine， the Affiliated Panyu Central Hospital of Guangzhou Medical University

Objective: To take Baihui (GV20) and Fengchi (GB20) targeting inflammatory response to regulate migraine as an example to describe a new method for studying the mechanism of stimulating ***: The target information of Baihui (GV20) and Fengchi (GB20) was retrieved， and after intersection with migraine， Kyoto Encyclopedia of Genes and Genomes (KEGG)， Reactome， and UniProt Keywords were used for functional enrichment. After selecting the main pathway， rats were selected and nitroglycerin was used for modeling， and the behavioral scores， inflammatory factors， heme oxygenase 1 (HMOx1)， protein kinase B (AKT1)， signal transducer and activator of transcription 3 (STAT3)， phosphorylated extracellular signal-regulated kinase 1/2 (P-ERK1/ERK2) and other states of the rats in the acupuncture， twisting， and electroacupuncture groups were ***: A total of 135 Baihui (GV20) targets and 27 Fengchi (GB20) targets were collected. A total of 73 target information were obtained after the intersection of these targets in migraine. These 73 targets have three main pathways: hypoxia-inducible factor 1 (HIF-1) signaling pathway， signaling by interleukins and inflammatory response. The main targets in the pathway were verified and found that interleukin-1 beta (IL-1β)， interleukin-6 (IL-6)， tumor necrosis factor-alpha (TNF-α) and HMOx1， AKT1， STAT3， P-ERK1/ERK2 can be regulated by Baihui (GV20) and Fengchi (GB20).Conclusion: Baihui (GV20) and Fengchi (GB20) can regulate migraine by regulating inflammatory factors and HMOx1， AKT1， STAT3， P-ERK1/ERK2 and other changes in HIF-1 signaling pathway， Signaling by Interleukins and Inflammatory response pathways. Based on systems biology and network pharmacology， and with the model of "acupoint-target-disease"， explore the research methods of systematic acupuncture and moxibustion. We believe this is a usable research direction for exploring the mechanism of acupuncture stimulation.

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Towards the diffusion source cost reduction for NdFeB grain boundary diffusion process

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journal of Materials Science & Technology 2020年第1期36卷 50-54页

作者： H.x.Zeng Z.W.Liu j.S.Zhang x.F.Liao H.Y.yu School of Materials Science and Engineering South China University of TechnologyGuangzhou 510640China

Aiming at improving the performance/cost ratio in grain boundary diffusion process(GBDP),the critical RE containing Pr-Al-Cu alloy,less expensive RE containing La-Al-Cu alloy and non-RE Al-Cu alloy were employed as the diffusion *** preliminary results show that the coercivity was successfully enhanced from 1000 kA/m to 1695,1156 and 1125 kA/m by Pr70Al20Cu10,La70Al20Cu10 and Al75Cu25(at.%) alloys diffusion,respectively,due to the formation of(Nd,Pr)-Fe-B,La2 O3 and c-Nd2 O3 phases respectively,after *** is also found that the corrosion resistance can be improved by Al-Cu diffusion due to the positive effects of Al and Cu elements in grain *** present results demonstrated the various coercivity enhancement mechanisms for the GBDP based on different diffusion sources,and provided feasible solutions for cost reduction of GBDP and NdFeB production by saving RE resource.

关键词： Grain boundary diffusion Cost reduction Coercivity Microstructure Corrosion resistance