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Enhancing alkyne semi-hydrogenation through engineering metal-support interactions of Pd on oxides

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Nano Research 2024年第5期17卷 3707-3713页

作者： Yuefeng Wu Xiaotong lu Pengfei Cui Wenyu Jia Jun Zhou yuan Wang Hussain Zahid Yuxin Wu Muhammad Umer Rafique Xiong Yin Baoshan Li Leyu Wang Guolei xiang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China

Supported Pd catalysts show superior activities for olefin productions from alkynes through semi-hydrogenation reactions,but over-hydrogenation into alkanes highly decreases olefin *** phenylacetylene semi-hydrogenation as a model reaction,here we explore the optimization approaches toward better Pd catalysts for alkyne semi-hydrogenation through investigating support effect and metal-support *** results show that the states of Pd with supports can be tuned by varying oxide reducibility,loading ratios,and *** our system,0.06 wt.%Pd on rutile-TiO_(2) nanorods shows the highest activity owing to the synergistic effects of single-atoms and *** reducibility can change the filling degrees of Pd 4d orbitals through varying interfacial bonding strengths,which further affect catalytic activity and selectivity.

关键词： alkyne semi-hydrogenation support effect metal-support interaction Pd catalyst single-atom catalyst

Spectrally resolved Franson interference

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 11-17页

作者： Rui-Bo Jin Zi-Qi Zeng Dan Xu Chen-Zhi yuan Bai-Hong Li You Wang Ryosuke Shimizu Masahiro Takeoka Mikio Fujiwara Masahide Sasaki Pei-xiang lu Hubei Key Laboratory of Optical Information and Pattern Recognition Wuhan Institute of TechnologyWuhan 430205China School of Physics and Information Science Shaanxi University of Science and TechnologyXi'an 710021China Southwest Institute of Technical Physics Chengdu 610041China Graduate School of Informatics and Engineering University of Electro-CommunicationsTokyo 182-8585Japan Department of Electronics and Electrical Engineering Keio UniversityKanagawa 223-8522Japan National Institute of Information and Communications Technology Tokyo 184-8795Japan

Franson interference can be used to test the nonlocal features of energy-time entanglement and has become a standard in quantum ***,most of the previous Franson interference experiments were demonstrated in the time domain,and the spectral properties of Franson interference have not been fully ***,we theoretically and experimentally demonstrate spectrally resolved Franson interference using biphotons with different correlations,including positive correlation,negative correlation,and *** is found that the joint spectral intensities of the biphotons can be modulated along both the signal and idler directions,which has potential applications in generating high-dimensional frequency entanglement and time-frequency grid *** work may provide a new perspective for understanding the spectral-temporal properties of the Franson interferometer.

关键词： resolved correlation spectral

Improved Non-uniformity Correction Method for Uncooled Microbolometer

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Semiconductor Photonics and Technology 2005年第4期11卷 266-269,286页

作者： MENG Li-ya yuan xiang-hui lu Guo-lin HUANG You-shu Key Lab. of Optoelectron. Technol. and Syst. for the Education Ministry of China Chongqing University Chongqing 400044 CHN

The uncooled microbolometer has a severe temperature requirement for non-uniformity correction. An improved two-point non-uniformity correction method is proposed, which can operate in wider uniform substrate temperatures. This method can control the bias voltage of MOS transistors by memory and DAC to meet two restrictions about responsivity and offset before traditional two-point calibration is implemented. The simulation results seem that this non-uniformity correction can work at uniform substrate temperature with fluctuant range of 4K.

关键词： Microbolometer Non-uniformity correction Substrate temperature

Inelastic Scattering of Dark Matter with Heavy Cosmic Rays

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Research in Astronomy and Astrophysics 2024年第6期24卷 68-80页

作者： Keyu lu Yue-Lin Sming Tsai Qiang yuan Le Zhang School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area SYSUZhuhai 519082China Peng Cheng Laboratory Shenzhen 518000China

We investigate the impact of inelastic collisions between dark matter(DM)and heavy cosmic ray(CR)nuclei on CR *** approximate the fragmentation cross-sections for DM-CR collisions using collider-measured proton-nuclei scattering cross-sections,allowing us to assess how these collisions affect the spectra of CR boron and *** derive new CR spectra from DM-CR collisions by incorporating their cross-sections into the source terms and solving the diffusion equation for the complete network of reactions involved in generating secondary *** a specific example with a coupling strength of b_(χ)=0.1 and a DM mass of m_(χ)=0.1 GeV,considering a simplified scenario where DM interacts exclusively with oxygen,a notable modification in the boron-to-carbon spectrum due to the DM-CR interaction is ***,the peak within the spectrum,spanning from 0.1 to 10 GeV,experiences an enhancement of approximately 1.5 ***,in a more realistic scenario where DM particles interact with all CRs,this peak can be amplified to twice its original *** the latest data from AMS-02 and DAMPE on the boron-to-carbon ratio,we estimate a 95%upper limit for the effective inelastic cross-section of DM-proton as a function of DM *** findings reveal that at m_(χ)?2 MeV,the effective inelastic cross-section between DM and protons must be less than O(10^(-32))cm^(2).

关键词： elementary particles nuclear reactions nucleosynthesis abundances scattering astroparticle physics (cosmology:)dark matter

Distributed active vibration control for helicopter based on diffusion collaboration

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Chinese Journal of Aeronautics 2024年第8期37卷 208-232页

作者： Yang yuan Yang lu Xunjun MA Jingliang LI Huiyu YUE National Key Laboratory of Helicopter Aeromechanics Nanjing University of Aeronautics and AstronauticsNanjing 210016China Wuhan Second Ship Design and Research Institute Wuhan 430205China

The active vibration control technology has been successfully applied to several helicopter ***,with the increasing of control scale,traditional centralized control algorithms are experiencing significant increase of computational complexity and physical implementation *** address this issue,a diffusion collaboration-based distributed Filtered-x Least Mean Square algorithm applied to active vibration control is proposed,drawing inspiration from the concept of data fusion in wireless sensor *** algorithm distributes the computation load to each node,and constructs the active vibration control network topology of large-scale system by discarding the weak coupling secondary paths between nodes,achieving distributed active vibration *** order to thoroughly validate the effectiveness and superiority of this algorithm,a helicopter fuselage model is designed as the research ***,the excellent vibration reduction performance of the proposed algorithm is confirmed through ***,specialized node control units are developed,which utilize STM32 microcontroller as the processing ***,a distributed control system is constructed based on multi-processor *** on this foundation,a large-scale active vibration control experimental platform is *** on the platform,experiments are carried out,involving the 4-input 4-output system and the 8-input 8-output *** experimental results demonstrate that under steady-state harmonic excitation,the proposed algorithm not only ensures control effectiveness but also reduces computational complexity by 50%,exhibiting faster convergence speed compared with traditional centralized *** time-varying external excitation,the proposed algorithm demonstrates rapid tracking of vibration changes,with vibration amplitudes at all controlled points declining by over 94%,proving the strong robustness and adaptive capability of the algorithm

关键词： Helicopter Active vibration control Diffusion collaboration Distributed control Experiment

Ballistic performance of spaced multi-ply soft fabrics: Experimental and numerical investigation

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Defence Technology（防务技术） 2024年第4期34卷 143-155页

作者： Zhongwei Zhang Xiaoning Yang yuan Lin Ziming Xiong Yuhang xiang Yi Zhou Mingyang Wang State Key Laboratory of Explosion&Impact and Disaster Prevention&Mitigation Army Engineering University of PLANanjing 210007China School of Mechanical Engineering Nanjing University of Science&TechnologyNanjing 210007China State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200China Postdoctoral Station of Civil Engineering Army Engineering University of PLANanjing 210007China

It has been reported that the ply gap influences the ballistic resistance of spaced multi-ply fabric systems,but its working mechanism was not well-understood. This paper reports the experimental and numerical approaches and results of an investigation on the mechanisms that enable the improved ballistic performance of spaced multi-ply systems. Penetration tests were performed over a range of impact velocities ranging from 200 m/s to 400 m/s. The results confirmed that the ply gap is beneficial to the energy absorption capability of the systems. This is because the front plies tend to absorb more energy when they are not immediately constrained by the rear plies. During a ballistic event, the gap relieves the reflection of the compressive pulse, prolonging the projectile engagement time with the front plies;on the other hand, the rear plies become increasingly less active in dissipating energy as the gap *** the gap is sufficiently widened to avoid any interference between the plies before the failure of the front ply, the responses of the whole system no longer vary. It was also found that the ballistic performance of the spaced systems is influenced by ply thickness, impact velocity, and the stacking order of the ply gap.

关键词： Energy absorption capability Ply gap Ballistic performance The front ply The rear ply

Design methodology,synthesis,and control strategy of the high-speed planetary rover

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Frontiers of Mechanical Engineering 2024年第2期19卷 59-74页

作者： Renchao lu Haibo GAO Zhen LIU Runze yuan Zongquan DENG State Key Laboratory of Robotics and Systems Harbin Institute of TechnologyHarbin 150001China

The planned missions to explore the surfaces of the Moon and Mars require high exploration efficiency,thus imposing new demands on the mobility system of planetary *** this paper,a design method for a high-speed planetary rover(HPR)is proposed,and the representative configurations are modeled and ***,the influence of the planetary surface environment on the design of HPRs is analyzed,and the design factors for HPRs are determined by studying a single-wheel ***,a design methodology for HPRs is *** adaptive suspension mechanisms of a four-wheeled rover are synthesized using the all-wheel-attachment condition and position and orientation characteristics theory,which are expressed in the form of a graph theory for the increase in elastic components and active ***,a dynamic model is built,and a simulation is carried out for the proposed *** validity of the proposed method and rover is verified,thus highlighting their potential application in future planetary exploration.

关键词： design methodology spectrum analysis high-speed planetary rover type synthesis

Microphysical Insights into a Tornadic Supercell from Dual-Polarization Radar Observations in Jiangsu, China on 14 May 2021

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Journal of Meteorological Research 2024年第2期38卷 303-320页

作者： Chao yuan Yang BAI Pengfei SUN Hua BAI lu XIA China Meteorological Administration Tornado Key Laboratory Foshan 528315 Institute of Atmospheric Environment China Meteorological AdministrationShenyang 110166 Panjin National Climate Observatory Panjin 124010 Yangzhou Meteorological Bureau of Jiangsu Province Yangzhou 225100 Yichun Meteorological Bureau of Heilongjiang Province Yichun 153000

Tornadoes are incredibly powerful and destructive natural events,yet the microphysical characteristics of the parent storm and its effects on tornadogenesis remain *** study analyzed polarization radar data of a tornadic supercell that occurred in Jiangsu Province of China on 14 May 2021,in comparison with another tornadic supercell and two non-tornadic supercells that occurred in the same region in *** two tornadic supercells exhibited lower differential reflectivity(ZDR)in the hook echo region compared with the non-tornadic supercells,indicating smaller median drop sizes.A distinct increase in ZDR from the melting of frozen hydrometeors,observed between2.5-and 4.0-km altitude in the non-tornadic storms,was absent in the tornadic *** non-tornadic supercells also displayed substantially higher specific differential phase(KDP)below the melting level,likely aroused from enhanced melting and *** findings suggest fundamental microphysical contrasts between tornadic and nontornadic ***,tornadic supercells have smaller droplets and may reduce melting in hook ***,greater separation between the ZDR arc and the KDP foot was observed during *** vertical gradient of KDP related to the cooling pool strength of the hook echo,regulating rear-flank downdraft *** the limited number of cases investigated,the findings of this study indicate that monitoring ZDR,KDP,and drop size distribution trends could assist with tornado prediction and warnings.

关键词： tornado polarimetric radar supercell hook echo drop size distribution

Flower-like tin oxide membranes with robust three-dimensional channels for efficient removal of iron ions from hydrogen peroxide

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Chinese Journal of Chemical Engineering 2024年第1期65卷 1-7页

作者： Risheng Shen Shilong Li Yuqing Sun yuan Bai Jian lu Wenheng Jing State Key Laboratory of Materials-Oriented Chemical Engineering Nanjing Tech UniversityNanjing 210009China National Energy Group Science and Technology Research Institute Co. Ltd.Nanjing 210023China

Membrane technology has become the mainstream process for the production of electronic grade hydrogen peroxide(H_(2)O_(2)).But due to the oxidation degradation of the organic membranes(***)by the strong oxidative radicals(e.g.OH)generated via the activation of H_(2)O_(2)by iron ions(Fe^(3+)),the short effective lifetime of membranes remains a *** nano tin oxide(SnO_(2))has great potential for the removal of Fe^(3+)in strongly oxidative H_(2)O_(2)because of its ability to stabilize H2O_(2)and preferentially adsorb Fe^(3+).Herein,we have designed for the first time a flower-like robust SnO_(2)membrane on the ceramic support by in situ template-free one-step hydrothermal *** three-dimensional loose pore structure in the membrane built by interlacing SnO_(2)nanosheets endows the SnO_(2)membrane with a high specific surface area and abundant adsorption sites(AOH).Based on the coordination complexation and electrostatic attraction between the SnO_(2)surface and Fe^(3+),the membrane shows a high Fe3+removal efficiency(83%)and permeability(24 L·m^(-2)·h^(-1)·MPa^(-1))in H_(2)O_(2).This study provides an innovative and simple approach to designing robust SnO_(2)membranes for highly efficient removal of Fe^(3+)in harsh environments,such as strong oxidation conditions.

关键词： Hydrogen peroxide SnO_(2)membrane Adsorption Hydrothermal