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Selective Hydrodeoxygenation of Lignin-Derived Vanillin via Hetero-Structured High-Entropy Alloy/Oxide Catalysts

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Energy & Environmental Materials 2024年第3期7卷 206-214页

作者： Yan Sun Kaili Liang Ren Tu Xudong Fan Charles q.jia Zhiwen jia Yingnan Li Hui Yang Enchen jiang Hanwen Liu Yonggang Yao Xiwei Xu Key Laboratory for Biobased Materials and Energy of Ministry of Education College of Materials and EnergySouth China Agricultural University Department of Chemical Engineering and Applied Chemistry University of Toronto State Key Laboratory of Materials Processing and Die & Mould Technology School of Materials Science and EngineeringHuazhong University of Science and Technology

The chemoselective hydrodeoxygenation of natural lignocellulosic materials plays a crucial role in converting biomass into value-added *** their complex molecular structures often require multiple active sites synergy for effective activation and achieving high ***,it is reported that a high-entropy alloy (HEA) on high-entropy oxide (HEO)hetero-structured catalyst for highly active,chemoselective,and robust vanillin *** heterogenous HEA/HEO catalysts were prepared by thermal reduction of senary HEOs (NiZnCuFeAIZrOx),where exsolvable metals (e.g.,Ni,Zn,Cu) in situ emerged and formed randomly dispersed HEA nanoparticles anchoring on the HEO *** catalyst exhibits excellent catalytic performance:100%conversion of vanillin and 95%selectivity toward high-value 2-methyl-4 methoxy phenol at low temperature of 120℃,which were attributed to the synergistic effect among HEO matrix(with abundant oxygen vacancies),anchored HEA nanoparticles (having excellent hydrogenolysis capability),and their intimate hetero-interfaces(showing strong electron transferring effect).Therefore,our work reported the successful construction of HEA/HEO heterogeneous catalysts and their superior multifunctionality in biomass conversion,which could shed light on catalyst design for many important reactions that are complex and require multifunctional active sites.

关键词： biomass conversion heterogeneous catalysts high-entropy oxide high-entropy alloys lignin pyrolysis

Electromagnetic Performance Analysis of Variable Flux Memory Machines with Series-magnetic-circuit and Different Rotor Topologies

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 3-11页

作者： qiang Wei Z.q.Zhu Yan jia jianghua Feng Shuying guo Yifeng Li Shouzhi Feng Department of Electronic and Electrical Engineering The University of SheffieldSheffield S13JDU.K. IEEE the CRRC Zhuzhou Institute Company Ltd. Zhuzhou 412001China

In this paper,the electromagnetic performance of variable flux memory(VFM)machines with series-magnetic-circuit is investigated and compared for different rotor *** on a V-type VFM machine,five topologies with different interior permanent magnet(IPM)arrangements are evolved and optimized under same *** on two-dimensional(2-D)finite element(FE)method,their electromagnetic performance at magnetization and demagnetization states is *** reveals that the iron bridge and rotor lamination region between constant PM(CPM)and variable PM(VPM)play an important role in torque density and flux regulation(FR)***,the global efficiency can be improved in VFM machines by adjusting magnetization state(MS)under different operating conditions.

关键词： Memory machine Permanent magnet Rotor topologies Series magnetic circuit Variable flux

Construction and Validity of Chinese Translation of the Universal Mental Health Literacy Scale for Adolescents

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International Journal of Mental Health Promotion 2024年第8期26卷 671-677页

作者： Wang q. Ji Y. Chen K. Li K. jia F. Peng T. School of Education and Psychology University of Jinan Jinan 250022 China Psychology Research group Jinan Quanjing Middle School Jinan 250024 China

Background: In this study, the Universal Mental Health Literacy Scale for Adolescents (UMHL-A) was revised and tested for its reliability and validity in Chinese middle school students, thus establishing a useful tool for assessing the mental health of individuals in this occupation. Methods: Our sample comprised 1208 junior high school students (58.85% male), aged between 11 and 15 years old. The Chinese version of the scale includes a mental health attitude subscale and mental health knowledge subscale, including attitudes towards seeking help, attitudes related to stigma, general mental health knowledge, and knowledge about specific mental illnesses, encapsulated in a total of 17 items. A series of psychometric analyses such as exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and internal consistency reliability estimation were carried out in this study. Results: The results of the CFA indicated that the two-factor model had an acceptable model fit (Attitude (UMHL-A Likert): χ2/df = 4.107; RMSEA = 0.072; SRMR = 0.045; TLI = 0.932; CFI = 0.954; Knowledge (UMHL-A T/F): χ2/df = 3.647; RMSEA = 0.066; SRMR = 0.044; TLI = 0.923; CFI = 0.945). The Cronbach’s alpha coefficient of subscales of the Chinese version UMHL-A were 0.80 and 0.78, respectively. Conclusion: In general, the Chinese version of the Universal Mental Health Literacy Scale for adolescents has good reliability and validity and can be used as a tool to measure the mental health literacy of Chinese adolescents. © 2024 The Authors.

关键词： adolescents Chinese Mental health literacy validity

Multiphase Interfacial Regulation Based on Hierarchical Porous Molybdenum Selenide to Build Anticorrosive and Multiband Tailorable Absorbers

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Nano-Micro Letters 2024年第1期16卷 85-105页

作者： Tianbao Zhao Zirui jia Jinkun Liu Yan Zhang guanglei Wu Pengfei Yin College of Science Sichuan Agricultural UniversityYa’an 625014People’s Republic of China Institute of Materials for Energy and Environment State Key Laboratory of Bio‑Fibers and Eco‑TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071People’s Republic of China

Electromagnetic wave(EMW)absorbing materials have an irreplaceable position in the field of military stealth as well as in the field of electromagnetic pollution *** in order to cope with the complex electromagnetic environment,the design of multifunctional and multiband high efficiency EMW absorbers remains a tremendous *** this work,we designed a three-dimensional porous structure via the salt melt synthesis strategy to optimize the impedance matching of the ***,through interfacial engineering,a molybdenum carbide transition layer was introduced between the molybdenum selenide nanoparticles and the three-dimensional porous carbon matrix to improve the absorption behavior of the *** analysis indicates that the number and components of the heterogeneous interfaces have a significant impact on the EMW absorption performance of the absorber due to mechanisms such as interfacial polarization and conduction loss introduced by interfacial ***,the prepared MoSe_(2)/MoC/PNC composites showed excellent EMW absorption performance in C,X,and Ku bands,especially exhibiting a reflection loss of−59.09 dB and an effective absorption bandwidth of 6.96 gHz at 1.9 *** coordination between structure and components endows the absorber with strong absorption,broad bandwidth,thin thickness,and multi-frequency absorption ***,it can effectively reinforce the marine anticorrosion property of the epoxy resin coating on q235 steel *** study contributes to a deeper understanding of the relationship between interfacial engineering and the performance of EMW absorbers,and provides a reference for the design of multifunctional,multiband EMW absorption materials.

关键词： Interfacial engineering Anticorrosion Multiband Electromagnetic wave absorber

Viscoacoustic generalized screen propagator in constant-q model

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Petroleum Science 2024年第4期21卷 2356-2369页

作者： Zhong-Kui Dai jia-Chun You Xing-guo Huang Wei Liu College of geophysics Chengdu University of Technology College of Instrumentation and Electrical Engineering Jilin University

When seismic waves propagate through the geological formation, there is a significant loss of energy and a decrease in imaging resolution, because of the viscoacoustic properties of subsurface medium. This profoundly impacts seismic wavefield propagation, imaging and interpretation. To accurately image the true structure of subsurface medium, the consensus among geophysicists is to no longer treat subsurface medium as ideal homogeneous medium, but rather to incorporate the viscoacoustic properties of subsurface medium. Based on the generalized screen propagator using conventional acoustic wave equation(acoustic gSP), our developed method introduces viscoacoustic compensation strategy, and derives a one-way wave generalized screen propagator based on time-fractional viscoacoustic wave equation(viscoacoustic gSP). In numerical experiments, we conducted tests on two-dimensional multi-layer model and the Marmousi model. When comparing with the acoustic gSP using the acoustic data, we found that the imaging results of the viscoacoustic gSP using the viscoacoustic data showed a significant attenuation compensation effect, and achieved imaging results for both algorithms were essentially consistent. However, the imaging results of acoustic gSP using viscoacoustic data showed significant attenuation effects, especially for deep subsurface imaging. This indicates that we have proposed an effective method to compensate the attenuated seismic wavefield. Our application on a set of real seismic data demonstrated that the imaging performance of our proposed method in local areas surpassed that of the conventional acoustic gSP. This suggests that our proposed method holds practical value and can more accurately image real subsurface structures while enhancing imaging resolution compared with the conventional acoustic gSP. Finally, with respect to computational efficiency, we gathered statistics on running time to compare our proposed method with conventional q-RTM, and it is evid

关键词： One-way wave equation Viscoacoustic wave equation generalized screen propagator Attenuation and dispersion effects

quartz-enhanced multiheterodyne resonant photoacoustic spectroscopy

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Light(Science & Applications) 2024年第4期13卷 696-705页

作者： jiapeng Wang Hongpeng Wu Angelo Sampaolo Pietro Patimisco Vincenzo Spagnolo Suotang jia Lei Dong State Key Laboratory of quantum Optics and quantum Optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006China. Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China. PolySense Lab Dipartimento Interateneo di FisicaUniversity and Politecnico of BariCNR-IFNVia Amendola 17370126 BariItaly

The extension of dual-comb spectroscopy(DCS)to all wavelengths of light along with its ability to provide ultralarge dynamic range and ultra-high spectral resolution,renders it extremely useful for a diverse array of applications in physics,chemistry,atmospheric science,space science,as well as medical *** this work,we report on an innovative technique of quartz-enhanced multiheterodyne resonant photoacoustic spectroscopy(qEMR-PAS),in which the beat frequency response from a dual comb is frequency down-converted into the audio frequency *** this way,gas molecules act as an optical-acoustic converter through the photoacoustic effect,generating heterodyne sound *** conventional DCS,where the light wave is detected by a wavelengthdependent photoreceiver,qEMR-PAS employs a quartz tuning fork(qTF)as a high-q sound transducer and works in conjunction with a phase-sensitive detector to extract the resonant sound component from the multiple heterodyne acoustic tones,resulting in a straightforward and low-cost hardware *** novel qEMRPAS technique enables wavelength-independent DCS detection for gas sensing,providing an unprecedented dynamic range of 63 dB,a remarkable spectral resolution of 43 MHz(or~0.3 pm),and a prominent noise equivalent absorption of 5.99×10^(-6)cm^(-1)·Hz-1/2.

关键词： quartz hardware resonant

All-dielectric terahertz metasurface governed by bound states in the continuum with high-q factor

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 44-54页

作者： Li Kun Zhao Xu Wang Meng jia Xingning Zhao Ruiqi Lu guizhen School of Integrated Circuit Science and Engineering Tianjin University of TechnologyTianjin 300384China School of Electronic and Electrical Engineering Ningxia UniversityYinchuan 750021China qILU Aerospace Information Research Institute Chinese Academy of Sciences(CAS)Jinan 250101China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing 100024China

The method of terahertz(THz)resonance with a high-quality(high-q)factor offers a vital physical mechanism for metasurface sensors and other high-q factor ***,it is challenging to excite the resonance with a high-q factor in metasurfaces with proper sensitivity as well as figure of merit(FOM)***,an all-dielectric metasurface composed of two asymmetrical rectangular blocks is *** and silicon are the materials applied for the substrate and cuboids *** distinct resonance governed by bound states in the continuum(BIC)is excited by forming an asymmetric cluster by a novel hybrid method of cutting and moving the *** investigation focuses on analyzing the transmission spectra of the metasurface under different variations in structural parameters and the loss of silicon refractive *** the proposed defective metasurface serves as a transmittance sensor,it shows a q factor of 1.08×10^(4)and achieves an FOM up to 4.8×10^(6),which is obtained under the asymmetric parameter equalling 1μ***,the proposed defective metasurface is sensitive to small changes in refractive *** the thickness of the analyte is 180μm,the sensitivity reaches a maximum value of 578 gHz/***,the proposed defective metasurface exhibits an extensive number of possible applications in the filters,biomedical diagnosis,security screening,and so on.

关键词： terahertz(THz)metasurface high-quality(high-q)factor bound states in the continuum figure of merit(FOM)

Ceramic-based meta-material absorber with high-temperature stability

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Rare Metals 2024年第9期43卷 4433-4440页

作者： Xing-Cong Chen Wei-jia Luo Run-Ni Zhao Yong-Zheng Wen Ji Zhou State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua University

With the continuous exploration of uncharted and extreme environments,enhanced temperature robustness of passive devices has become particularly *** this study,a ceramic-based meta-material absorber with exceptional temperature stability is developed using a fusion design approach that combines rare metal-based tungsten bronze structural ceramics and ***,the absorbance of the meta-material array based on Mie resonance exceeds 49.0%in both waveguides and free space,approaching the theoretical *** to impedance analysis,the absorption performance can be distinctly correlated with the dielectric loss （q_f）.Notably,the high-temperature robustness is verified to still be effective at 400℃.These advancements in our design allow for the use of monolithic materials in fabricating temperature-stable perfect absorbers,providing greater freedom in the dielectric performance and expanding their potential applications,including in space exploration and 5g millimeter-wave scenarios.

关键词： Meta-material absorber Microwave absorption Miniaturization Rare metal-based ceramics Temperature robustness

Satellite observations of coastal upwelling in the northern Arafura Sea

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Journal of Oceanology and Limnology 2024年第2期42卷 361-376页

作者： Zheyuan YU Zhanjiu HAO Zhenhua XU Peiwen ZHANg jia YOU Baoshu YIN Hongwei YANg College of Mathematics and System Science Shandong University of Science and TechnologyQingdao 266590China CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China Pilot National Laboratory for Marine Science and Technology(qingdao) Qingdao 266237China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China CAS Engineering Laboratory for Marine Ranching Institute of OceanologyChinese Academy of SciencesQingdao 266071China

Coastal upwelling is significant for marine ecosystems by lifting nutrient-rich deep waters into the euphotic zone,thereby increasing primary and secondary *** satellite observations show that the northern Arafura Sea(NAS),especially in the coastal region,features high chlorophyll-a(chl-a)concentrations,implying a strong coastal ***,coastal upwelling in the NAS has not received much *** on a semi-automatic image processing technology,the seasonal and interannual variability of coastal upwelling in the NAS are investigated in this study using satellite-observed sea surface temperature(SST)and wind *** results suggest that there are seasonal coastal upwelling events in the NAS modulated by upwelling-favorable southeast monsoon(SEM).The annual mean days,mean area,and annual mean intensity of coastal upwelling events during the SEM season are 92 days,6514 km^(2),and-5.31×10^(5),respectively,while the corresponding values during the northwest monsoon(NWM)season are 32 days,5569 km^(2),and-1.41×10^(5).It is also found that the SEM coastal upwelling in the NAS displays prominent interannual *** strong upwelling events are found in 2010,2013,2016,and 2017 when the southeast monsoon winds were *** analysis suggests that at the interannual scale,the upwelling index(UI)averaged in the SEM season is negatively correlated with that of three upwelling *** can be attributed to the limitation of onshore geostrophic flow which is evidenced by the negative correlation between the UI and the alongshore difference in sea surface *** study highlights the important role of the southeast monsoon in the temporal variability of coastal upwelling in the NAS.

关键词： coastal upwelling the northern Arafura Sea southeast monsoon interannual variability