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Structure of the mantle transition zone in the central and western parts of the North China Craton using the receiver function 3D Kirchhoff migration method

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Science China Earth Sciences 2024年第9期67卷 2783-2795页

作者： min ZHU Qingju wu Jieyuan NING Ruiqing ZHANG Institute of Geophysics China Earthquake AdministrationBeijing 100081China Institute of Theoretical and Applied Geophysics Peking UniversityBeijing 100871China

Using data from the regional broadband dense temporary array deployed by the ChinArray project,we applied the three-dimensional(3D)Kirchhoff migration method of the teleseismic P-wave receiver function to investigate discontinuity structures of the mantle transition zone(MTZ)in the central and western parts of the North China Craton(NCC)using a highresolution 3D velocity model of the East Asian *** results show that the 410-km discontinuity beneath the Datong Volcano is depressed by~10 km,indicating the presence of a high-temperature anomaly near the depth of 410 km,which is likely related to small-scale mantle upwelling caused by the dehydration of the stagnant Pacific Plate in the *** upwelling of hot material provides a heat source for surface magmatic *** the Bohai Bay Basin,significant subsidence of the 660-km discontinuity is observed,and the transition zone here is extensively ***’s suggested that the anomalies in this region are related to the stagnation of the Pacific slab in the *** the thickness of the transition zone west of the North-South Gravity lineament appears normal,we propose that the subducting front of the Pacific slab did not cross the gravity lineament in the *** comparison,the small-scale subsidence of the 660-km discontinuity and the thickening of the MTZ observed north of the Hannuoba Volcano likely indicate that the slab crossed the gravity lineament at its turning point and remained in the ***,a local thickening of the MTZ is observed in the Dabie orogenic belt of the Qinling *** is believed to be a combined effect of lithospheric del.mination into the transition zone in the lower Yangtze region and the stagnation of the Pacific Plate.

关键词： North China Craton Mantle transition zone Receiver function migration Datong Volcano

Dietary selection of commensal protists:expanding host immunity by impacting trans-kindom competition with bacteria

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Signal Transduction and Targeted Therapy 2024年第6期9卷 2344-2346页

作者： Bo li min wu Huaqiong li Department of Neonatology The Second Affliated Hospital of Wenzhou Medical University and Yuying Children’s HospitalWenzhou Medical UniversityWenzhouZhejiang 325027China Zhejiang Engineering Research Center for Tissue Repair Materials Wenzhou InstituteUniversity of Chinese Academy of SciencesWenzhouZhejiang 325000China

In a recent publication in Cell,1 Elias *** and colleagues identified novel commensal parabasalid protists(***,Parabasalia_sp_1653)with distinct metabolic traits,including diverse succinate excretion and dietary preference,which drives different trans-kingdom competition with specific commensal bacteria and results in divergent small intestine(SI)immune response,highlighting the significance of dietary interventions as a pivotal strategy for maintaining gut health(Fig.1).

关键词： immunity dietary intestine

Hydrothermal hydrogenation/deoxygenation of palmitic acid to alkanes over Ni/activated carbon catalyst

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Chinese Journal of Chemical Engineering 2024年第2期66卷 8-18页

作者： min lin Yuhao Yan Xiaoxian li Rui li Yulong wu MOE Engineering Center of Forestry Biomass Materials and Bioenergy Beijing Forestry UniversityBeijing 100083China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China Key laboratory of Advanced Reactor Engineering and Safety of ministry of Education Tsinghua UniversityBeijing 100084China

To produce paraffin from hydrogenation/deoxygenation of palmitic acid,model compound of bio-oil obtained by hydrothermal liquefaction(HTl)of microalgae has been an attractive focus in recent *** order to avoid energy-intensive separation process of water and bio-oil,it is of importance that deoxygenation upgrading of fatty acids under hydrothermal conditions similar to HTl ***,it is the first time to explore the application of activated carbon(AC)-supported non-noble-metal catalysts,such as Ni,Co,and Mo,and so on,in the hydrothermal hydrogenation/deoxygenation of long-chain fatty acids,and the obtained Ni/AC-H(the Ni/AC was further H_(2)pre-reduced)is one of the best *** addition,it is found that the catalytic activity can be further improved by H_(2)pre-reduction of *** results that are more low valences of nickel and oxygen vacancy can be obtained after H_(2)pre-reduction,thus significant promoting the deoxygenation especially the decarbonylation pathway of fatty *** total alkanes yield can reaches 95.9%at optimal conditions(280℃,360 min).This work confirmed that the low-priced AC-supported non-noble-metal catalysts have great potential compared with the noble-metal catalyst,in hydrothermal upgrading of bio-oil.

关键词： Bio-oil Fatty acids Deoxygenation Hydrothermal upgrading

Hybrid Dynamic Variables-Dependent Event-Triggered Fuzzy Model Predictive Control

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 723-733页

作者： Xiongbo Wan Chaoling Zhang Fan Wei Chuan-Ke Zhang min wu IEEE the School of Automation China University of Geosciencesthe Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systemsand the Engineering Research Center of Intelligent Technology for Geo-ExplorationMinistry of EducationWuhan 430074China

This article focuses on dynamic event-triggered mechanism(DETM)-based model predictive control(MPC) for T-S fuzzy systems.A hybrid dynamic variables-dependent DETM is carefully devised,which includes a multiplicative dynamic variable and an additive dynamic *** addressed DETM-based fuzzy MPC issue is described as a “min-max” optimization problem(OP).To facilitate the co-design of the MPC controller and the weighting matrix of the DETM,an auxiliary OP is proposed based on a new lyapunov function and a new robust positive invariant(RPI) set that contain the membership functions and the hybrid dynamic variables.A dynamic event-triggered fuzzy MPC algorithm is developed accordingly,whose recursive feasibility is analysed by employing the RPI *** the designed controller,the involved fuzzy system is ensured to be asymptotically *** examples show that the new DETM and DETM-based MPC algorithm have the advantages of reducing resource consumption while yielding the anticipated performance.

关键词： Dynamic event-triggered mechanism(DETM) hybrid dynamic variables model predictive control(MPC) robust positive invariant(RPI)set T-S fuzzy systems

Nonlocal coherence harvesting from quantum vacuum

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Communications in Theoretical Physics 2024年第7期76卷 44-51页

作者： Rui-Di Wang Shu-min wu Xiao-li Huang Department of Physics Liaoning Normal UniversityDalian 116029China

It is well known that nonlocal coherence reflects nonclassical correlations better than quantum entanglement. Here, we analyze nonlocal coherence harvesting from the quantum vacuum to particle detectors adiabatically interacting with a quantum scalar field in minkowski *** find that the harvesting-achievable separation range of nonlocal coherence is larger than that of quantum entanglement. As the energy gap grows sufficiently large, the detectors harvest less quantum coherence, while the detectors could extract more quantum entanglement from the vacuum state. Compared with the linear configuration and the scalene configuration, we should choose the model of equilateral triangle configuration to harvest tripartite coherence from the vacuum. Finally, we find a monogamous relationship, which means that tripartite l_(1)-norm of coherence is essentially bipartite types.

关键词： nonlocal coherence quantum vacuum monogamous relationship

Sliding behaviors of the trapezoidal roof rock block under a lateral dynamic disturbance

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 741-760页

作者： Feng Dai Wancheng Zhu min Ren Shunchuan wu leilei Niu Faculty of land Resources Engineering Kunming University of Science and TechnologyKunming650093China Center for Rock Instability and Seismicity Research Department of Mining EngineeringSchool of Resource and Civil EngineeringNortheastern UniversityShenyang110819China

The surrounding rock of underground space is always affected by external dynamic disturbance from the side position,such as blasting vibration from a stope at the same level or seismic waves from adjacent strata.A series of laboratory tests,numerical simulations and theoretical analyses were carried out in this study to disclose the sliding mechanism of roof rock blocks under lateral ***,the experiments on trapezoidal key block under various clamping loads and disturbance were conducted,followed by numerical simulations using the fast lagrangian analysis of continua(FlAC3D).Then,based on the conventional wave propagation model and the classical shear-slip constitutive model,a theoretical model was proposed to capture the relative displacement between blocks and the sliding displacement of the key *** results indicate that the sliding displacement of the key block increased linearly with the disturbance energy and decreased exponentially with the clamping load when the key block was disturbed to slide(without instability).Meanwhile,when the key block was disturbed to fall,two types of instability process may appear as immediate type or delayed *** addition,the propagation of stress waves in the block system exhibited obvious low-velocity and lowfrequency characteristics,resulting in the friction reduction effect appearing at the contact interface,which is the essential reason for the sliding of rock *** results can be applied to practical underground engineering and provide valuable guidance for the early detection and prevention of rockfalling disasters.

关键词： lateral dynamic disturbance Trapezoidal rock block system low-velocity and low-frequency wave Friction reduction effect Instability mode

Evaluation of COVID-19 outbreak prevention and control in Beijing using the emergency management theory

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Fundamental Research 2024年第3期4卷 671-677页

作者： Yu wu Jue liu min liu School of Public Health Peking UniversityBeijing 100191China

On April 29,2020,China entered a normalization stage of prevention and *** December 2021,more than 40 outbreaks had occurred in China,which reflected the shortcomings of the pandemic prevention and control measures in China at that *** the capital city of China,Beijing faces more pressure in epidemic prevention and *** used the COVID-19 cluster containment evaluation indicators to determine the effects of prevention and control measures on four COVID-19 outbreaks in *** considering the specificity and operability of evaluation indicators and the availability of evaluation data,the evaluation system in our study consisted of six dimensions:epidemic prevention and control effect,discovery and detection ability,precision prevention and control capability,public protection effect,medical treatment and nosocomial infection prevention and control ability,and information release and public opinion response *** composite scores of the prevention and control effects of the Xinfadi,Shunyi,Daxing,and Ejina Banner–associated COVID-19 outbreaks in Beijing were 62,82,87,and 76,*** the six dimensions,the epidemic prevention and control effect,discovery and detection ability,precision prevention and control capability,and public protection effect scores for the Xinfadi outbreak were lower than those for the Shunyi,Daxing and Ejina Banner–associated *** medical treatment and nosocomial infection prevention and control ability scores for the outbreak associated with Ejina Banner were lower than those for the Xinfadi,Shunyi,and Daxing *** managing cluster outbreaks,Beijing was able to detect index cases early enough to reduce the scale and duration of the outbreak and consistently release official information to reduce public panic,standardize the management of centralized quarantine sites to prevent cross-infection,adhere to the“dynamic COVID‐zero”strategy to accurately prevent and control outbreaks,reduce the societa

关键词： Cluster outbreaks COVID-19 Prevention and control Evaluation Beijing

Plasmon-assisted mode selection lasing in a lanthanide-based microcavity

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Advanced Photonics 2024年第3期6卷 35-41页

作者： lei Guo min Ji Bowen Kang min Zhang Xin Xie Zihao wu Huan Chen Volker Deckert Zhenglong Zhang Shaanxi Normal University School of Physics and Information Technology Friedrich-Schiller University Leibniz Institute of Photonic Technology

lanthanide-based microlasers have attracted considerable attention owing to their large anti-Stokes shifts, multiple emission bands, and narrow linewidths. Various applications of microlasers, such as optical communication, optical storage, and polarization imaging, require selecting the appropriate laser polarization mode and remote control of the laser properties. Here, we propose a unique plasmon-assisted method for the mode selection and remote control of microlasing using a lanthanide-based microcavity coupled with surface plasmon polaritons(SPPs) that propagate on a silver microplate. With this method, the transverse electrical(TE) mode of microlasers can be easily separated from the transverse magnetic(TM) mode. Because the SPPs excited on the silver microplate only support TM mode propagation, the reserved TE mode is resonance-enhanced in the microcavity and amplified by the local electromagnetic field. Meanwhile, lasingmode splitting can be observed under the near-field excitation of SPPs due to the coherent coupling between the microcavity and mirror microcavity modes. Benefiting from the long-distance propagation characteristics of tens of micrometers of SPPs on a silver microplate, remote excitation and control of upconversion microlasing can also be realized. These plasmon-assisted polarization mode-optional and remote-controllable upconversion microlasers have promising prospects in on-chip optoelectronic devices, encrypted optical information transmission, and high-precision sensors.

关键词： lanthanide-based microlaser surface plasmon polaritons polarization mode selection

Surface tension of single suspended aerosol microdroplets

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Chinese Chemical letters 2024年第4期35卷 520-524页

作者： Yukai Tong Zhijun wu Bo Zhou min Hu Anpei Ye Key laboratory for the Physics and Chemistry of Nanodevices School of ElectronicsPeking UniversityBeijing 100871China State Key Joint laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China

The surface tension of troposphere aerosols can significantly influence their atmospheric processes and key properties, particularly on the morphology, the phase transition, the activation as cloud condensation nuclei, and the gas-particle partitioning. However, directly measuring the surface tension of single ambient aerosol is quite challenging, due to the limitations of their picolitre volumes and thermal motion. Here, we developed a dual laser tweezers Raman spectroscopy(DlT-RS) system to directly sense the surface tension of single airborne microdroplets(PM10particles). A pair of aerosol droplets were trapped and driven to coalesce by the laser tweezers. Meanwhile, the backscattering light intensity and brightfield images during the coalescence process were recorded to characterize the aerosol surface tension. A remarkable advantage of directly sensing aerosol surface tension is that the solutes in aerosols are often supersaturated, which is common in atmospheric aerosols but almost unavailable in bulk *** experimentally measured the surface tension of aerosols composed of nitrates or oxalic acid/nitrate mixture. Besides, the variation of surface tension during aerosol aging process was also explored, which brings possible implications on the surface evolution of actual ambient aerosol during their atmospheric lifetime.

关键词： Surface tension Droplet coalescence Single aerosol laser tweezers Aerosol aging