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Journal of Rare Earths 2024年第6期42卷 1036-1045,I0002页

作者： Yuefei Xiang Hong li Hongzhi Zhang lin yang Canyuan liao Tongsheng yang Junpeng li Zewen guo Jing Zhu Key Laboratory of LCR Materials and Devices of Yunnan Province Yunnan Key Laboratory of Carbon Neutrality and Green Low-carbon TechnologiesSchool of Materials and Energy Yunnan UniversityKunming650091China

At present,with the increasing application needs of phosphor-converted white light-emitting diode(wLED),the synthetic efficiency and thermal stability of phosphor become urgent ***,this research reports a microwave-assisted fast synthesis approach to obtain a Sm^(3+)-activated borotellurate Na_(2)Y_(2)TeO_(4)(BO_(3))_(2)(NYTB)red phosphor with high crystallinity,excellent thermostability,and low chromaticity *** the NYTB-based phosphor,in contrast to the conventional solid-state synthesis,the microwave-assisted synthesis method involves lower synthesis temperature and shorter processing ***,the concentration quenching mechanism was *** w-LED device packaged with the studied phosphor exhibits a near-standard white light with proper CCT and high Ra parameters.

关键词： Borotellurate Samarium Microwave-assisted synthesis Red-emitting Thermal stability Rareearths

Propylene epoxidation coupled with furfural oxidation over Pt(Ⅱ?) TPP porphyrin with molecular oxygen

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green Chemical Engineering 2024年第4期5卷 519-525页

作者： Hong-Qi li Hai-yang Yu yang li Xiao-Qi He Xian-Tai Zhou Huizhou Research Institute Sun Yat-sen University School of Chemical Engineering and Technology Sun Yat-sen University

The development of green route for preparing propylene oxide (PO) with molecular oxygen is of significance both in academic and industrial. In this work, propylene epoxidation coupled with furfural oxidation catalyzed by platinum meso-tetraphenylporphyrin (Pt (II)TPP) has been developed. Propylene conversion and PO selectivity reached up to 56%and 83%, respectively. Meanwhile, furfural was almost completely converted to furoic *** on operando characterizations and electron paramagnetic resonance (EPR) tests, a mechanism involved high-valent Pt species was proposed. This work is expected to provide a potential application prospects for producing PO and furoic acid simultaneously in chemical industry.

关键词： Propylene Epoxidation Molecular oxygen Furfural Platinum porphyrins

Effect of Heat Treatment on Microstructure and Mechanical Behavior of Cu-Bearing 316L Stainless Steel Produced by Selective Laser Melting

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 169-180页

作者： Huan yang Ying liu Jianbo Jin Kunmao li Junjie yang lingjian Meng Chunbo li Wencai Zhang Shengfeng Zhou Sino-german College of Intelligent Manufacturing Shenzhen Technology UniversityShenzhen518118China Institute of Advanced Wear and Corrosion Resistance and Functional Materials Jinan UniversityGuangzhou510632China Department of Orthopedics First Affiliated Hospital of Jinan UniversityGuangzhou510632China

Cu-bearing stainless steels(SSs)with high strength,excellent plasticity,and effective antimicrobial properties hold significant potential for applications in the marine *** this study,Cu-bearing SSs with copper ranging from 0 to 6.0 wt%were successfully prepared using selective laser melting(SLM)*** the Cu-bearing SSs with different copper contents,the effect of heat treatment on the microstructural and mechanical behaviors was studied *** observations revealed that the subgrain size of Cu-bearing SSs increased with heat treatment at 500℃ and 700℃ for 6 ***,the tensile strength and elongation increased after the heat treatment temperature due to the combined effect of dislocations,twins,andε-Cu precipitated ***,after heat treatment at 700℃,the SLM4.5Cu sample exhibited an abnormal rise in tensile strength and *** finding suggests that the diffusion strengthening caused byε-Cu precipitates exceeded the stacking fault ***,the tensile strength and elongation reached 693.32 MPa and 56.94%,*** work provides an efficient approach for preparing Cu-bearing SSs with exceptional strength and plasticity.

关键词： Selective laser melting Cu-bearing stainless steel(SS) Heat treatment Mechanical properties

On Leray's problem in an infinitely long pipe with the Navier-slip boundary condition

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Science China Mathematics 2024年第4期67卷 819-854页

作者： Zijin li Xinghong Pan Jiaqi yang School of Mathematics and Statistics Nanjing University of Information Science and TechnologyNanjing 210044China School of Mathematics and Key Laboratory of Ministry of Industry and Information Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Mathematics and Statistics Northwestern Polytechnical UniversityXi'an 710129China

The original Leray’s problem concerns the well-posedness of weak solutions to the steady incompressible Navier-Stokes equations in a distorted pipe,which approach the Poiseuille flow subject to the no-slip boundary condition at spatial *** this paper,the same problem with the Navier-slip boundary condition instead of the no-slip boundary condition,is *** to the complexity of the boundary condition,some new ideas,presented as follows,are introduced to handle the extra difficulties caused by boundary ***,the Poiseuille flow in the semi-infinite straight pipe with the Navier-slip boundary condition will be introduced,which will serve as the asymptotic profile of the solution to the generalized Leray’s problem at spatial ***,a solenoidal vector function defined in the whole pipe,satisfying the Navierslip boundary condition,having the designated flux and equalling the Poiseuille flow at a large distance,will be carefully *** plays an important role in reformulating our ***,the energy estimates depend on a combined L2-estimate of the gradient and the stress tensor of the velocity.

关键词： stationary Navier-Stokes system Navier-slip boundary condition Leray's problem

Alleviating limit cycling in training gANs with an optimization technique

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Science China Mathematics 2024年第6期67卷 1287-1316页

作者： Keke li liping Tang Xinmin yang National Center for Applied Mathematics in Chongqing Chongqing Normal UniversityChongqing401331China School of Mathematical Sciences University of Electronic Science and Technology of ChinaChengdu611731China

In this paper,we undertake further investigation to alleviate the issue of limit cycling behavior in training generative adversarial networks(gANs)through the proposed predictive centripetal acceleration algorithm(PCAA).Specifically,we first derive the upper and lower complexity bounds of PCAA for a general bilinear game,with the last-iterate convergence rate notably improving upon previous ***,we combine PCAA with the adaptive moment estimation algorithm(Adam)to propose PCAA-Adam,for practical training of gANs to enhance their generalization ***,we validate the effectiveness of the proposed algorithm through experiments conducted on bilinear games,multivariate gaussian distributions,and the CelebA dataset,respectively.

关键词： gANs general bilinear game predictive centripetal acceleration algorithm lower and upper complexity bounds PCAA-Adam

Implications of mosquito metabolism on vector competence

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Insect Science 2024年第3期31卷 674-682页

作者： li gao Wenxu yang Jingwen Wang State Key Laboratory of genetic Engineering School of Life SciencesFudan UniversityShanghaiChina Ministry of Education Key Laboratory of Contemporary Anthropology School of Life SciencesFudan UniversityShanghaiChina

Mosquito-borne diseases(MBDs)annually kill nearly half a million *** to the lack of effective vaccines and drugs on most MBDs,disease prevention relies primarily on controlling *** huge efforts having been put into mosquito control,eco-friendly and sustainable mosquito-control strategies are still lacking and urgently *** mosquito-transmitted pathogens have lost the capacity of de novo nutrition biosynthesis,and rely on their vertebrate and invertebrate hosts for sustenance during the long-term obligate parasitism ***,a better understanding of the metabolic interactions between mosquitoes and pathogens will contribute to the discovery of novel metabolic targets or regulators that lead to reduced mosquito populations or vector *** review summarizes the current knowledge about the effects of mosquito metabolism on the transmission of multiple *** also discuss that research in this area remains to be explored to develop multiple biological prevention and control strategies for MBDs.

关键词： flaviviruses mosquito metabolism Plasmodium vector competence

Robotic compliant assembly for complex-shaped composite aircraft frame based on gaussian process considering uncertainties

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Chinese Journal of Aeronautics 2024年第10期37卷 471-482页

作者： Yingke yang Dongsheng li Yunong ZHAI Jie WANg Lei XUE Zhiyong yang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Ningbo Institute of Technology Beihang UniversityNingbo 3158002China COMAC Shanghai Aircraft Manufacturing Co. Ltd.Shanghai 201324China

Robots are finding increasing application in aircraft composite structure assembly due to their flexibility and the growing demand of aircraft manufacturers for high production *** contact force of the composite frame in a robotic assembly of the aircraft composite fuselage panel can hardly be controlled due to the multi-surface variable contact stiffness caused by compliance and complex shape with multiple mating *** paper proposes a robotic assembly system for the aircraft composite fuselage frame with a compliant contact force control strategy using the gaussian process surrogate ***,a robotic assembly system is introduced,and the global coordinate system transformation model is ***,a compliant force control architecture is designed to generate the desired output ***,a gaussian process surrogate model with uncertainties is utilized to model the complicated relationship between the robot’s output force and the normal contact force acting on the mating surface of the composite ***,an optimal contact force control strategy is implemented to improve the contact ***,an experiment demonstrates that the proposed methodology can ensure that the contact force on each surface is within the limit of the engineering specification and uniformly distributed,improving the quality compared to the traditional assembly process.

关键词： Aircraft Composite structure assembly Multi-surface contact Compliant control gaussian process Uncertainty

Mars exploration——In situ K-Ar dating of jarosite

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Science China Earth Sciences 2024年第3期67卷 641-656页

作者： Jing yang Dewen ZHENg Ying WU Hong CHEN li yang Bin ZHANg Key Laboratory of Active Tectonics and geological Safety Ministry of Natural ResourcesInstitute of GeomechanicsChinese Academy of Geological SciencesBeijing 100081China State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China Institute of Earth Sciences China University of GeosciencesBeijing 100083China Key Laboratory of Cenozoic geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029Chin

To accurately determine the chronological framework of climatic variations recorded by various Martian terrains, the absolute ages of Martian events and cratering rate need to be constrained by either in situ dating or returned samples. In situ K-Ar dating is currently a more plausible dating technique as compared with sample return. Jarosite(KFe_(3)[SO_(4)]_(2)[OH]_(6)) is the only confirmed K sulfate mineral that is widely present on Mars, as indicated by in situ detection, orbital remote sensing, and meteorite studies. Jarosite can be used for precise K-Ar and (40)Ar/(39)Ar dating. The preservation of jarosite on Mars provides information about the nature and duration of aqueous processes on the Martian surface. Different ages of Martian jarosite represent the key to constraining the transition from Martian surface water activity to arid climatic conditions. This paper summarizes recent advances in our knowledge of the spatial distribution of Martian jarosite, its mineralogical properties and stability on Mars, the Ar diffusion kinetics of jarosite, and the current status of in situ K-Ar dating. Moreover, we examine the key scientific issues to be addressed for in situ K-Ar dating of jarosite and Martian sample return missions, and discuss future research directions.

关键词： Mars Jarosite In situ K-Ar dating Ar diffusion Stability

WEAK-STRONg UNIQUENESS FOR THREE DIMENSIONAL INCOMPRESSIBLE ACTIVE liQUID CRYSTALS

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Acta Mathematica Scientia 2024年第4期44卷 1415-1440页

作者： Fan yang Congming li School of Mathematical Sciences CMA-ShanghaiShanghai Jiao Tong UniversityShanghai 200240China

The hydrodynamics of active liquid crystal models has attracted much attention in recent years due to many applications of these *** this paper,we study the weak-strong uniqueness for the Leray-Hopf type weak solutions to the incompressible active liquid crystals in R^(3).Our results yield that if there exists a strong solution,then it is unique among the Leray-Hopf type weak solutions associated with the same initial data.

关键词： analysis of parabolic and elliptic types weak-strong uniqueness active liquid crystals weak solution energy equality

Facet-dependent activation of oxalic acid over hematite nanocrystals under the irradiation of visible light for efficient degradation of pollutants

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Journal of Environmental Sciences 2024年第8期142卷 204-214页

作者： Zhixio.g yang Yuan li Xiaotian Wang Jiaming li Jiquan Wang gaoke Zhang Hubei Key Laboratory of Mineral Resources Processing and Environment State Key Laboratory of Silicate Materials for ArchitecturesWuhan University of TechnologyWuhan 430070China Hubei Engineering Consulting Co. Ltd.Wuhan 430071China

Naturally occurring hematite has been widely studied in the Fenton-like system for water pollutant remediation due to its abundance and ***,its inadequate catalytic activity results in difficulty in effectively degrading pollutants in the catalytic degradation system that it ***,we constructed a photochemical system composed of hematite with{001}facet of high activity facet and low-cost and non-toxic oxalic acid(OA)for the removal of various types of *** removal rate for the degradation of metronidazole,tetracycline hydrochloride,Rhodamine B,and hexavalent chromium by hematite nanoplate with the exposed{001}facet activating OA under visible light irradiation was 4.75,2.25,2.33,and 2.74 times than that by the exposed{110}facet,*** functional theory(DFT)calculation proved that the OA molecule was more easily adsorbed on the{001}facet of hematite than that on the{110}facet,which would favor the formation of the more Fe(Ⅲ)-OA complex and reactive *** addition,the reactive site of metronidazole for the attraction of radicals was identified on the basis of the DFT calculation on the molecular occupied orbitals,and the possible degradation pathway for metronidazole included carbon chain fracture,hydroxyethyl-cleavage,denitrogenation,and ***,this finding may offer a valuable direction in designing an efficient iron-based catalyst based on facet engineering for the improved activity of Fenton-like systems such as OA activation.

关键词： Hematite Facet exposure Oxalic acid activation Fenton-like system Pollutant removal