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Phase transfer-based high-efficiency recycling of precious metal electrocatalysts

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Green Chemical Engineering 2024年第1期5卷 68-74页

作者： Qing Zeng Shaonan tian Yu Zhang hui Liu Dong Chen Xinlong tian Chaoquan Hu Jun Yang State Key Laboratory of multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing100190China State Key Laboratory of marine Resource Utilization in South China Sea Hainan Provincial Key Lab of Fine ChemistrySchool of Chemical Engineering and TechnologyHainan UniversityHaikou570228China Nanjing IPE Institute of Green manufacturing Industry Nanjing211100China Center of materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China

Recycling precious metals with high-efficiency is undoubtedly beneficial to optimize resource utilization for environmental remediation and sustainable ***,we report an efficient route to recycle the palladium(Pd)and platinum(Pt)electrocatalysts using a phase transfer *** strategy involves acidic dissolution of deactivated precious metal(Pd/Pt)electrocatalysts from their loading substrates,mixing with an ethanolic solution of dodecylamine(DDA),subsequent extraction of metal ions into a non-polar organic phase,and final reduction by sodium borohydride to reproduce high-performance electrocatalysts towards typical electrochemical reactions,e.g.,oxygen reduction reaction(ORR)and ethanol oxidation reaction(EOR).In specific,the transfer efficiencies are up to 98%and the final recovery rate is over 85%for Pd and Pt electrocatalysts in each *** approach symbolizes a facile and efficient way to recover precious metals,which might be applied to recycling a wide range of metals in various realms after appropriate modifications.

关键词： Precious metal Phase transfer Extraction Recovery Electrocatalyst

Energy beam-based direct and assisted polishing techniques for diamond:A review

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International Journal of Extreme manufacturing 2024年第1期6卷 93-124页

作者： Zhuo Li Feng Jiang Zhengyi Jiang Zige tian tian Qiu Tao Zhang Qiuling Wen Xizhao Lu Jing Lu hui Huang Institute of manufacturing Engineering Huaqiao UniversityXiamen 361021People’s Republic of China School of mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW 2522Australia College of mechanical Engineering and Automation Huaqiao UniversityXiamen 361021People’s Republic of China State Key Laboratory of High Performance Tools Huaqiao UniversityXiamen 361021People’s Republic of China

Diamond is a highly valuable material with diverse industrial applications,particularly in the fields of semiconductor,optics,and high-power ***,its high hardness and chemical stability make it difficult to realize high-efficiency and ultra-low damage machining of *** address these challenges,several polishing methods have been developed for both single crystal diamond(SCD)and polycrystalline diamond(PCD),including mechanical,chemical,laser,and ion beam processing *** this review,the characteristics and application scope of various polishing technologies for SCD and PCD are ***,various energy beam-based direct and assisted polishing technologies,such as laser polishing,ion beam polishing,plasma-assisted polishing,and laser-assisted polishing,are *** current research progress,material removal mechanism,and infuencing factors of each polishing technology are *** some of these methods can achieve high material removal rates or reduce surface roughness,no single method can meet all the ***,the future development prospects and application directions of different polishing technologies are presented.

关键词： single crystal diamond polycrystalline diamond energy beam polishing technology material removal mechanism influencing factors

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Quantum weak force sensing with squeezed magnomechanics

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Science China(Physics,mechanics & Astronomy) 2024年第10期Mechanics & Astronomy) .卷 27-36页

作者： Qian Zhang Jie Wang tian-Xiang Lu Ran Huang Franco Nori hui Jing Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of ministry of Education Department of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal University College of Physics and Electronic Information Gannan Normal University Theoretical Quantum Physics Laboratory Cluster for Pioneering ResearchRIKEN Center for Quantum Computing RIKEN Department of Physics University of Michigan Academy for Quantum Science and Technology Zhengzhou University of Light Industry

Cavity magnomechanics, exhibiting remarkable experimental tunability, rich magnonic nonlinearities, and compatibility with various quantum systems, has witnessed considerable advances in recent years. However, the potential benefits of using cavity magnomechanical(Cmm) systems in further improving the performance of quantum-enhanced sensing for weak forces remain largely unexplored. Here we show that, by squeezing the magnons, the performance of a quantum Cmm sensor can be significantly enhanced beyond the standard quantum limit(SQL). We find that, for comparable parameters, two orders of magnitude enhancement in the force sensitivity can be achieved in comparison with the case without magnon squeezing. moreover, we obtain the optimal parameter regimes of homodyne angle for minimizing the added quantum noise. Our findings provide a promising approach for highly tunable and compatible quantum force sensing using hybrid Cmm devices, with potential applications ranging from quantum precision measurements to quantum information processing.

关键词： quantum force sensing cavity magnomechanics magnon Kerr effect

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Enhancing reversible hydrogen storage performance of 2LiBH4–mgH2 via in-situ building heterogeneous nucleation sites

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Rare metals 2024年第9期43卷 4367-4376页

作者： Wei Chen Ya-hui Sun tian Xu Xue-Bin Yu Guang-Lin Xia Department of materials Science Fudan University

2LiBH4-mgH2composite is one of the most attractive reactive hydride composites with a theoretic hydrogen capacity of 10.8 wt%.However,the large nucleation restriction of mgB2during the second step of dehydrogenation results in sluggish hydrogen storage kinetics and high operating temperature,which hinders its practical application as on-board hydrogen storage ***,Al3Ti doped Al nanoparticles （AT NPs） are prepared by a facile chemical reduction reaction to improve the hydrogen storage performance of *** the initial H2desorption process,mgAlB4and TiB2that have identical crystal structure and low d-value mismatch with mgB2resulting from the reaction between AT NPs and 2LiBH4-mgH2composite serve as effective nucleation sites for the formation of *** a result,the apparent activation energy of the two-step H2desorption of AT NPs doped 2LiBH4-mgH2composite are notably decreased to （110.0±5.9） and（119.6±1.4） kJ·mol-1,which is 55.5 and 33.5 kJ·mol-1lower than that of the undoped *** importantly,a reversible hydrogen storage capacity of 9.2 wt%after 10cycles of H2desorption and adsorption could be achieved,corresponding to a capacity retention rate of 99%.The building of reactive bimetallic catalyst towards in situ formation of heterogeneous nucleation sites provides a new strategy for improving the hydrogen storage performance of reactive hydride composites.

关键词： Catalytic effects Heterogeneous nucleation Reactive hydride composites Reversible hydrogen storage

Insights into in-situ imbibition behavior of fracturing fluid in propped shale fractures based on nuclear magnetic resonance:A case study from Longmaxi Formation shale,Sichuan Basin,China

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Petroleum Science 2024年第1期21卷 410-429页

作者： Jing-Jing Guo Kai-Xiang Di Lie-hui Zhang Yu-Long Zhao hui-Ying Tang Rui-Han Zhang Ye tian National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina

Shale gas is an important component of unconventional oil and gas *** the imbibition behavior is helpful to optimize flowback parameters and enhance gas *** imbibition studies have focused on shale matrix,and the pressure conditions discussed were mostly *** initial imbibition behavior begins from propped fractures to matrix,but there are few studies working on explaining the imbibition behavior in propped fractures or the phenomenon of many shale wells exhibit higher productivity after a“soaking”***,propped fracture samples were designed for imbibition and migration *** order to accurately study the mechanism and main influencing factors of fracturing fluid imbibition and migration in propped and unpropped shale fractures under high temperature and high pressure,a series of experiments based on nuclear magnetic resonance(NmR)were carried *** showed that NmR T_(2) spectra of all samples exhibited a bimodal *** final imbibition volume of fracturing fluid was positively related to pressure and fracture *** imbibition effect of fracturing fluid was more evident in matrix pores under high *** the migration during soaking stage,the fracturing fluid gradually migrated from large pores to small pores and gradually displaced the shale gas from the matrix,thus allowing the water blocking in propped fractures to self-unlock to some *** permeability decreased in the imbibition stage,while it recovered in the migration stage to some extent.

关键词： Forced imbibition migration Soaking NmR T_(2)spectra Propped fracture Permeability recovery

Effects of surface morphology on tribological properties of Arapaima gigas scales

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Friction 2024年第7期12卷 1469-1482页

作者： Shuaijun ZHAng Pengpeng BAI Xiangli WEN Chengwei WEN hui CAO Wanyou YAng Yu tian State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Bionic Engineering(ministry of Education China)Jilin UniversityChangchun 130022China

The remarkable mechanical adaptability of arapaima(Arapaima gigas)scales has made them an important subject of ***,no research has been conducted into their tribological properties,which are crucial for the protectability and flexibility of *** this study,by combining morphological characterizations,friction experiments,and theoretical analyses,the relationship between the surface morphology and tribological properties of arapaima scales is *** results indicate that arapaima scales exhibit varying surface morphologies in different *** specifically,the exposed regions of scales feature grooves and a circulus,whereas the covered regions exhibit *** specific surface morphology of arapaima scales produces varying tribological properties across different regions and sliding *** unique tribological properties of arapaima scales influence the forces received from predator attacks and neighboring scales,directly influencing the arapaima’s protective *** study provides new insights into the mechanisms of natural flexible dermal armors,and it has potential applications in personal protective systems.

关键词： arapaima scales surface morphology tribological properties protectability

Spectral Index Distribution of Various Scale Components in Supernova Remnant Cassiopeia A

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Research in Astronomy and Astrophysics 2024年第5期24卷 211-217页

作者： Xianhuan Lei hui Zhu Zongyao Yin Haiyan Zhang Wenwu tian Xianchuan Yu Key Laboratory of Radio Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 101408China School of Artiﬁcial Intelligence Beijing Normal UniversityBeijing 100875China

Cassiopeia A(Cas A) is a well-known candidate for studying cosmic-ray acceleration, in which compact features of various scales have attracted much attention. Based on observations by the Very Large Array of Cas A at 6 cm and 21 cm, we measure the spectral index distribution of various scale components using the observation of the 1998 epoch. We decompose its total density image into nine scale components, and map the temperature spectral index distribution of each component, which ranges from-2.48 ± 0.01 to-2.91 ± 0.05. We find that the spectral indices increase from the small scale to large scale components. A damped post-shock magnetic field model with a strength larger than ~200 μG and a damping length scale less than ~10% of the remnant radius can account for the spectral index variation naturally.

关键词： ISm supernova remnants-(ISm:)cosmic rays-radio continuum ISm

SIRT1 inhibits apoptosis of human lens epithelial cells through suppressing endoplasmic reticulum stress in vitro and in vivo

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1205-1216页

作者： hui Cui Di Sun Sheng m.ng tian-Ju ma Zi Ye Zhao-hui Li medical School of Chinese PLA Beijing 100089China Senior Department of Ophthalmology the Third Medical Center of PLA General HospitalBeijing 100853China

AIm:To explore the effect of silent information regulator factor 2-related enzyme 1(SIRT1)on modulating apoptosis of human lens epithelial cells(HLECs)and alleviating lens opacification of rats through suppressing endoplasmic reticulum(ER)***:HLECs(SRA01/04)were treated with varying concentrations of tunicamycin(Tm)for 24h,and the expression of SIRT1 and C/EBP homologous protein(CHOP)was assessed using real-time quantitative polymerase chain reaction(RT-PCR),Western blotting,and *** morphology and proliferation was evaluated using an inverted microscope and cell counting kit-8(CCK-8)assay,*** the SRA01/04 cell apoptosis model,which underwent siRNA transfection for SIRT1 knockdown and SRT1720 treatment for its activation,the expression levels of SIRT1,CHOP,glucose regulated protein 78(GRP78),and activating transcription factor 4(ATF4)were *** potential reversal of SIRT1 knockdown effects by 4-phenyl butyric acid(4-PBA;an ER stress inhibitor)was *** vivo,age-related cataract(ARC)rat models were induced by sodium selenite injection,and the protective role of SIRT1,activated by SRT1720 intraperitoneal injections,was evaluated through morphology observation,hematoxylin and eosin(H&E)staining,Western blotting,and ***:SIRT1 expression was downregulated in Tminduced SRA01/04 ***,in SRA01/04 cells,both cell apoptosis and CHOP expression increased with the rising doses of *** stress was stimulated by Tm,as evidenced by the increased GRP78 and ATF4 in the SRA01/04 cell apoptosis *** of SIRT1 by siRNA knockdown increased ER stress activation,whereas SRT1720 treatment had opposite results.4-PBA partly reverse the adverse effect of SIRT1 knockdown on *** vivo,SRT1720 attenuated the lens opacification and weakened the ER stress activation in ARC rat ***:SIRT1 plays a protective role against Tm-induced apoptosis in HLECs and slows the progression of cataract in

关键词： silent information regulator factor 2-related enzyme 1 endoplasmic reticulum stress apoptosis human lens epithelial cells cataract

A survey on model-based reinforcement learning

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Science China(Information Sciences) 2024年第2期67卷 59-84页

作者： Fan-m.ng LUO tian XU Hang LAI Xiong-hui CHEN Weinan ZHAng Yang YU National Key Laboratory for Novel Software Technology Nanjing University Polixir. ai Department of Computer Science and Engineering Shanghai Jiao Tong University

Reinforcement learning(RL) interacts with the environment to solve sequential decision-making problems via a trial-and-error approach. Errors are always undesirable in real-world applications, even though RL excels at playing complex video games that permit several trial-and-error attempts. To improve sample efficiency and thus reduce errors, model-based reinforcement learning(mBRL) is believed to be a promising direction, as it constructs environment models in which trial-and-errors can occur without incurring actual costs. In this survey, we investigate mBRL with a particular focus on the recent advancements in deep RL. There is a generalization error between the learned model of a non-tabular environment and the actual environment. Consequently, it is crucial to analyze the disparity between policy training in the environment model and that in the actual environment, guiding algorithm design for improved model learning, model utilization, and policy training. In addition, we discuss the recent developments of model-based techniques in other forms of RL, such as offline RL, goal-conditioned RL, multi-agent RL, and meta-RL. Furthermore,we discuss the applicability and benefits of mBRL for real-world tasks. Finally, this survey concludes with a discussion of the promising future development prospects for mBRL. We believe that mBRL has great unrealized potential and benefits in real-world applications, and we hope this survey will encourage additional research on mBRL.

关键词： reinforcement learning model-based reinforcement learning planning model learning model learning with reduced error model usage