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Chinese Journal of Structural Chemistry 2024年第1期43卷 33-39页

作者： peng wang Daijie Deng Suqin Wu Li xu Institute for Energy Research School of Chemistry and Chemical EngineeringJiangsu UniversityZhenjiang212013China

As an oxygen reduction reaction(ORR)catalyst,nitrogen-doped carbon(NC)is widely used in zinc-air batteries(ZABs).However,NC catalysts exhibit low conductivity and insufficient exposure of active ***,a Co-based deep eutectic solvent(DES)was selected to modify NC catalyst(Co-NC)to improve ORR *** functional theory(DFT)calculation shows that the modification of Co-based DES can change the electronic structure of NC and increase metallic active sites,which is beneficial to the desorption of reaction intermediates on Co-NC,further improving ORR ***-NC shows excellent ORR performances and ***,ZABs assembled with Co-NC manifest a high maximum power density of 177.4 mW cm^(-2),a high specific capacity of 726.12 mA h g^(-1)and a charge-discharge cycle life of 500 *** study can provide practical reference for surface modified carbon-based electrocatalyst with DES to improve ORR performances.

关键词： Deep eutectic solvent Nitrogen-doped carbon Surface modification Oxygen reduction reaction Zinc-air battery

Ultrahigh strength and improved electrical conductivity in an aging strengthened copper alloy processed by combination of equal channel angular pressing and thermomechanical treatment

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Journal of Central South University 2024年第6期31卷 1823-1837页

作者： wang xu LI Zhou MENG Xiang-peng XIAO Zhu School of Materials Science and Engineering Central South UniversityChangsha 410083China Ningbo Boway Alloy Material Co. Ltd.Ningbo 315135China Key Laboratory of Non-ferrous Metal Materials Science and Engineering(Ministry of Education) Changsha 410083China

In this paper,equal channel angular pressing and thermomechanical treatment was employed to improve the strength and electrical conductivity of an aging strengthened Cu-Ti-Cr-Mg alloy,and the microstructure and properties of the alloy were investigated in *** results showed that the samples deformed by the combination of cryogenic equal channel angular pressing(ECAP)and rolling had good comprehensive properties after aging at 400℃.The tensile strength of the peak-aged and over-aged samples was 1120 MPa and 940 MPa,with their corresponding electrical conductivity of 14.7%IACS and 22.1%IACS,*** and cryogenic rolling introduced high density dislocations,leading to the inhibition of the softening effects and refinement of the *** a long time aging at 400℃,the alloy exhibited ultra-high strength with obvious increasing electrical *** high strength was attributed to the synergistic effect of work hardening,grain refinement strengthening and precipitation *** precipitation of a large amount of Ti atoms from the matrix led to the high electrical conductivity of the over-aged sample.

关键词： Cu-Ti alloy equal channel angular pressing rolling aging treatment high strength

Advancing space-based gravitational wave astronomy: Rapid parameter estimation via normalizing flows

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 20-33页

作者： Minghui Du Bo Liang He wang peng xu Ziren Luo Yueliang Wu Center for Gravitational Wave Experiment National Microgravity LaboratoryInstitute of MechanicsChinese Academy of SciencesBeijing 100190China Key Laboratory of Gravitational Wave Precision Measurement of Zhejiang Province Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of SciencesBeijing 100049China Taiji Laboratory for Gravitational Wave Universe(Beijing/Hangzhou) University of Chinese Academy of SciencesBeijing 100049China Lanzhou Center of Theoretical Physics Lanzhou UniversityLanzhou 730000China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China

Gravitational wave(GW) astronomy is witnessing a transformative shift from terrestrial to space-based detection, with missions like Taiji at the forefront. While the transition brings unprecedented opportunities for exploring massive black hole binaries(MBHBs), it also imposes complex challenges in data analysis, particularly in parameter estimation amidst confusion *** this gap, we utilize scalable normalizing flow models to achieve rapid and accurate inference within the Taiji environment. Innovatively, our approach simplifies the data's complexity, employs a transformation mapping to overcome the year-period time-dependent response function, and unveils additional multimodality in the arrival time parameter. Our method estimates MBHBs several orders of magnitude faster than conventional techniques, maintaining high accuracy even in complex backgrounds. These findings significantly enhance the efficiency of GW data analysis, paving the way for rapid detection and alerting systems and enriching our ability to explore the universe through space-based GW observation.

关键词： Taiji program gravitational wave detection parameter estimation machine learning

Post-treatment of Ti-MWW zeolite with potassium fluoride for propylene epoxidation

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FRONTIERS OF CHEMICAL SCIENCE AND ENGINEERING 2024年第8期18卷 88-0页

作者： Li, Xintong Gong, Xianchen wang, Jilong Jin, Shengbo xu, Hao Wu, peng East China Normal Univ Sch Chem & Mol Engn State Key Lab Petr Mol & Proc Engn Shanghai Key Lab Green Chem & Chem Proc Shanghai 200062 Peoples R China

Epoxidation of propylene to propylene oxide (PO) with hydrogen peroxide (HPPO) is an environmentally friendly and cost-efficient process in which titanosilicates are used as catalysts. Ti-MWW is a potential industrial catalyst for this process, which involves the addition of HPPO to PO. The silanol groups generated during secondary crystallization unavoidably result in ring-opening of PO and inefficient decomposition of HPPO, which diminish the PO selectivity and the lifespan of Ti-MWW. To address this issue, we conducted post-treatment modifications of the structured Bf-Ti-MWW catalyst with potassium fluoride aqueous solutions. By quenching the silanol groups with potassium fluoride and implanting electron-withdrawing fluoride groups into the Ti-MWW framework, both the catalytic activity and HPPO utilization efficiency were increased. Moreover, the ring opening reaction of PO was prohibited. In a continuous fixed-bed liquid-phase propylene epoxidation reaction, the KF-treated structured Ti-MWW catalyst displayed an exceptionally long lifespan of 2700 h, with a PO yield of 590 gkg-1h-1.

关键词： titanosilicates Ti-MWW propylene epoxidation structured catalyst KF modification ENHANCED CATALYTIC-ACTIVITY EFFICIENT EPOXIDATION ALKENE EPOXIDATION HYDROGEN-PEROXIDE WATER-ADSORPTION TITANOSILICATE TITANIUM PERFORMANCE ETHYLENE MECHANISM

WeldNet:A voxel-based deep learning network for point cloud annular weld seam detection

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Science China(Technological Sciences) 2024年第4期67卷 1215-1225页

作者： wang Hui RONG YouMin xu JiaJun XIANG SongMing peng YiFan HUANG Yu State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

Weld seam detection is an important part of automated *** present,few studies have been conducted on annular weld seams,and a lot of defects exist in the point cloud model of the tube sheet obtained by RGB-D cameras and photography *** at the above problems,this paper proposed an annular weld seam detection network named WeldNet where a voxel feature encoding layer was adaptively improved for annular weld seams,the sparse convolutional network and region proposal network(RPN)were used to detect annular weld seam position,and an annular weld seam detection loss function was ***,an annular weld seam dataset was established to train the *** with the random sampling consistency(RANSAC)method,WeldNet has a higher detection accuracy,as well as a higher detection success rate which has increased by 23%.Compared with U-Net,WeldNet has been proven to achieve a better detection result,and the intersection over the union of the weld seam detection is improved by 17.8%.

关键词： deep learning point cloud weld seam detection welding annular weld seam

Key parameter estimation for radar rotating object imaging with multi-aspect observations

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Science China(Information Sciences) 2010年第8期53卷 1641-1652页

作者： YE ChunMao, xu Jia , peng YingNing & wang XiuTan Department of Electronic Engineering, Tsinghua University, Beijing 100084, China Department of Electronic Engineering Tsinghua University Beijing China

Rotating object model is commonly used for imaging analysis in high resolution radars such as the inverse synthetic aperture radar (ISAR). For a rotating object, it is known that multi-aspect observations can improve cross-range resolution with the known imaging geometry. For the non-cooperative rotating object with unknown imaging geometry, this paper proposes an integrated scheme to estimate the key parameters, e.g., the rotating velocity and the aspect angle difference between every two observations. Furthermore, convolution back-projection (CBP) method is applied to provide fused imaging result with improved resolution. Also, the accuracy of the ultimate parameter estimation is analyzed, which is strongly related with several important factors like position extraction error of scattering centers and so on. Finally, the results of numerical experiments are provided to demonstrate the effectiveness of the proposed method.

关键词： rotating objects multi-aspect observations fused imaging aspect angle difference

Investigation on taste characteristics and sensory perception of soft-boiled chicken during oral processing based on electronic tongue and electronic nose

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Food Science and Human Wellness 2024年第1期13卷 313-326页

作者： Na xu Xianming Zeng peng wang Xing Chen Xinglian xu Minyi Han College of Food Science and Technology Nanjing Agricultural UniversityNanjing 210095China National Center of Meat Quality and Safety Control Nanjing Agricultural UniversityNanjing 210000China State Key Laboratory of Food Science and Technology Jiangnan UniversityWuxi 214122China Wens Foodstuff Co. Ltd.Yunfu 527400China

The sensory perception of food is a dynamic process,which is closely related to the release of flavor substances during oral ***’s not only affected by the food material,but also subjected to the individual oral *** explore the oral processing characteristics of soft-boiled chicken,the sensory properties,texture,particle size,viscosity,characteristic values of electronic nose and tongue of different chicken samples were *** correlation analysis showed that the physical characteristics especially the cohesiveness,springiness,resilience of the sample determined oral processing *** addition of chicken skin played a role in lubrication during oral *** particle size of the bolus was heightened at the early stage,and the fluidity was enhanced in the end,which reduced the chewing time to the swallowing point and raised the aromatic compounds signal of electronic *** the effect of chicken skin on chicken thigh with relatively high fat content,was opposite in electronic nose,which had a certain masking effect on the perception of umami and sweet *** conclusion,fat played a critical role in chicken oral processing and chicken thigh had obvious advantages in comprehensive evaluation of soft-boiled chicken,which was more popular among people.

关键词： Oral processing Chicken Electronic tongue Electronic nose

The biological functions and metabolic pathways of valine in swine

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Journal of Animal Science and Biotechnology 2024年第1期15卷 20-34页

作者： Chuni wang Yao peng Yiru Zhang Juan xu Sheng Jiang Leli wang Yulong Yin Institute of Subtropical Agriculture Chinese Academy of SciencesChangshaChina Hunan Provincial Key Laboratory of Animal Intestinal Function and Regulation College of Life SciencesHunan Normal UniversityChangshaChina Tianjin Institute of Industrial Biotechnology Chinese Academy of SciencesTianjinChina

Valine is an essential amino acid and a type of branched-chain amino acid. Due to the involvement of branchedchain amino acids in various metabolic pathways, there has been a surge of interests in valine nutrition and its role in animal physiology. In pigs, the interactions between valine and other branched-chain amino acids or aromatic amino acids are complex. In this review, we delve into the interaction mechanism, metabolic pathways, and biological functions of valine. Appropriate valine supplementation not only enhances growth and reproductive performances, but also modulates gut microbiota and immune functions. Based on past observations and interpretations, we provide recommended feed levels of valine for weaned piglets, growing pigs, gilts, lactating sows, barrows and entire males. The summarized valine nutrient requirements for pigs at different stages offer valuable insights for future research and practical applications in animal husbandry.

关键词： Additional dosage Biological function Metabolic pathway Pig Valine

Abnormal grain growth induced byδ→γphase transformation in Fe-based shape memory alloys

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Journal of Materials Science & Technology 2024年第5期172卷 196-201页

作者： Huabei peng Liqiu Yong Gaixia wang Jiazhen Yan Bing xu Yuhua Wen School of Mechanical Engineering Sichuan UniversityChengdu 610065China Science and Technology on Reactor Fuel and Materials Laboratory Nuclear Power Institute of ChinaChengdu 610041China

Grain boundaries,including low-angle,high-angle,and coinci-dence boundaries,are intrinsic interfaces in polycrystalline *** heat-treatment at sufficiently high temperatures,grain boundary migration occurs because the grain boundaries are ther-modynamically ***,grain growth occurs due to a decrease in grain boundary area after heat-treatment[1].In general,there are two types of grain growth:normal grain growth,where grains grow uniformly,and abnormal grain growth,where one or a few grains selectively grow and engulf surround-ing smaller grains,leading to the formation of large grains,some-times several millimeters or greater in size[2].The classical tech-nique to achieve abnormal grain growth is the strain-annealing method,which involves subjecting the material to a small strain followed by annealing[3,4].This method has been reported to ob-tain single-crystal wires or plates[1].Additionally,abnormal grain growth can be achieved by plastic straining at high temperatures,resulting in the fabrication of large grains or single crystals[5].However,the above methods are not applicable to components with complicated shapes due to the inevitable deformation ***,Omori et *** a simply method of abnor-mal grain growth to fabricate ultra-large grains,even single crys-tals,in Cu-Al-Mn[1],Fe-Mn-Al-Ni[2],and Fe-Mn-Al-Ni-Cr[6]*** method involves applying cyclic heat treatment between a high temperature BCC single-phase region and a low tempera-ture BCC+FCC two-phase region[1,2,6-12].Note that the cyclic heat treatment resulted in the formation of BCC sub-grain struc-tures responsible for abnormal grain growth[1,2,6-12].In addition,Yang et *** that abnormal grain growth occurred at above 900℃,and large-grains,even single crystals,were obtained only through annealing cast Cu-based polycrystalline alloys contained coherent nano-particles[13,14].Notably,the cyclic heat treatment and annealing cast alloys are deform

关键词： grain alloys deformation

Pt confined in Sn-ECNU-46 zeolite for efficient alkane dehydrogenation

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结构化学 2024年第4期43卷 15-23页

作者： Naihong wang Longkang Zhang Yejun Guan peng Wu Hao xu Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular Engineering East China Normal UniversityShanghai200062China State Key Laboratory of Petroleum Molecular & Process Engineering SKLPMPE Sinopec Research Institute of Petroleum Processing Co.LTD.Beijing100083China East China Normal University Shanghai200062China

Highly dispersed and stable Pt-based catalysts play a crucial role in constructing efficient catalytic systems for alkane *** this study,a novel bimetallic Pt-Sn catalyst confined in extra-large-pore ECNU-46 zeolite(denoted as Pt/Sn-ECNU-46)is prepared by *** open-site framework Sn species((SiO)3Sn-OH)serve as anchors to interact with Pt species,favoring the high dispersion of *** the other hand,the framework Sn species act as the second metal to regulate the geometrical and electronic environment of Pt species,thus suppressing their ***/Sn-ECNU-46 achieves a good performance in propane dehy-drogenation(PDH)reaction with high initial propane conversion(46％)and propylene selectivity(＞99％)as well as regeneration *** addition,Pt/Sn-ECNU-46 is also active in the dehydrogenation of *** study explores the application of extra-large-pore zeolite as support in constructing metal-confined catalysts for alkane dehydrogenation.

关键词： Alkane dehydrogenation Heteroatom-containing zeolite Zeolite confined catalyst Pt-based catalyst