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High-speed impulsive stimulated Brillouin microscopy

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Photonics Research 2024年第4期12卷 730-739页

作者： JIARUI li TAORAN le HONGYUAN ZHANG HAOYUN WEI YAN li State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China Cole Eye Institute Cleveland ClinicClevelandOhio 44195USA

Brillouin microscopy, which maps the elastic modulus from the frequency shift of scattered light, has evolved to a faster speed for the investigation of rapid biomechanical changes. Impulsive stimulated Brillouin scattering (ISBS)spectroscopy has the potential to speed up measurement through the resonant amplification interaction from pulsed excitation and time-domain continuous detection. However, significant progress has not been achieved due to the limitation in signal-to-noise ratio (SNR) and the corresponding need for excessive averaging to maintain high spectral precision. Moreover, the limited spatial resolution also hinders its application in mechanical imaging. Here, by scrutinizing the SNR model, we design a high-speed ISBS microscope through multi-parameter optimization including phase, reference power, and acquisition time. leveraging this, with the further assistance of the Matrix Pencil method for data processing, three-dimensional mechanical images are mapped under multiple contrast mechanisms for a millimeter-scale polydimethylsiloxane pattern immersed in methanol, enabling the identification of these two transparent materials without any contact or labeling. Our experimental results demonstrate the capability to maintain high spectral precision and resolution at a sub-millisecond integration time for one pixel. With a two-order improvement in the speed and a tenfold improvement in the spatial resolution over the state-of-the-art systems, this method makes it possible for ISBS microscopes to sensitively investigate rapid mechanical changes in time and space.

关键词： Brillouin maintain methanol

Combined Promoting Effects of Specific Organic Functional Groups and Alumina Surface Characteristics for the Design of a Highly Efficient NiMo/Al_(2)O_(3) Hydrodesulfurization Catalyst

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 1-11页

作者： li Huifeng li Mingfeng Zhang le Wang Wei Nie Hong National Energy R&D Center of Petroleum Refining Technology SINOPEC Research Institute of Petroleum Processing Co.Ltd.Beijing 100083China

To prepare a highly efficient NiMo/Al_(2)O_(3) hydrodesulfurization catalyst,the combined effects of specific organic functional groups and alumina surface characteristics were ***,the correlation between the surface characteristics of four different alumina and the existing Mo species states was *** was found that the Mo equilibrium adsorption capacity can be used as a specific descriptor to quantitatively evaluate the changes in surface characteristics of different alumina.A lower Mo equilibrium adsorption capacity for alumina means weaker metal-support interaction and the loaded Mo species are easier to transform into ***,the Mo-O-Al bonds still exist at the metal-support *** introduction of cationic surfactant hecadecyl trimethyl ammonium bromide(CTAB)can further improve Mo species dispersion through electrostatic attraction with Mo anions and interaction of its alkyl chain with the alumina surface;meanwhile,the introduction of ethylenediamine tetraacetic acid(EDTA)can complex with Ni ions to enhance the Ni-promoting effect on ***,the NiMo catalyst designed using alumina with lower Mo equilibrium adsorption capacity and the simultaneous addition of EDTA and CTAB exhibits the highest hydrodesulfurization activity for 4,6-dimethyl dibenzothiophene because of its proper metal-support interaction and more well-dispersed Ni-Mo-S active phases.

关键词： alumina Mo equilibrium adsorption capacity organic functional groups metal-support interaction hydrodesulfurization

High-resolution multi-scale air pollution system:Evaluation of modelling performance and emission control strategies

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Journal of Environmental Sciences 2024年第3期137卷 65-81页

作者： Diogo Lopes Joana Ferreira Sandra Rafael ka In Hoi Xin li Yuan liu ka-Veng Yuen kai Meng Mok Ana Isabel Miranda Department of Environment and Planning&CESAM University of AveiroAveiroPortugal Department of Civil&Environmental Engineering Faculty of Science and TechnologyUniversity of MacaoMacao SARChina

A high percentage of the world's population lives in areas where air pollutant concentrations exceed the World Health Organization *** work aims to develop and test,a high-resolution multi-scale air pollution modelling system by integrating a set of adequate *** system is able to provide detailed air pollutant concentrations in urban areas and support air quality management strategies through a better identification of different atmospheric *** also allows furthering the design and assessment of air pollution control measures for a specific *** evaluate its performance and suitability,the system was applied to the Macao Special Administrative Region(SAR),China,one of the most densely populated areas on earth,during a winter period when this area is affected by high levels of Particulate Matter(PM).Although the developed system tends to underestimate the PM concentrations,it revealed a good performance in reproducing the temporal and spatial air pollution *** exceedances of the Chinese air quality standards were calculated and high population exposure to PM pollution was *** tested urban atmospheric emission reduction scenarios have shown air quality improvements,indicating that emission reduction measures at urban level should focus on the domestic ***,it is crucial to implement joint pollution prevention strategies with neighbouring regions to improve the air quality in Macao *** approach developed in this work can support policymakers in defining new strategies to reduce atmospheric pollution in urban areas.

关键词： Urban areas High-resolution emission inventory Particulate matter Population exposure

Disturbances rejection optimization based on improved two-degree-of-freedom LADRC for permanent magnet synchronous motor systems

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Defence Technology（防务技术） 2024年第3期33卷 518-531页

作者： Chenggang Wang Jianhu Yan Wenlong li liang Shan le Sun School of Automation Nanjing University of Science and TechnologyNanjing 210094China

Permanent magnet synchronous motor(PMSM)speed control systems with conventional linear active disturbance rejection control(CLADRC)strategy encounter issues regarding the coupling between dynamic response and disturbance suppression and have poor performance in suppressing complex nonlinear *** order to address these issues,this paper proposes an improved two-degree-of-freedom LADRC(TDOF-LADRC)strategy,which can enhance the disturbance rejection performance of the system while decoupling entirely the system's dynamic and anti-disturbance performance to boost the system robustness and simplify controller parameter *** models that consider total disturbances are developed to design the TDOF-LADRC speed controller ***,to evaluate the control performance of the TDOF-LADRC strategy,its stability is proven,and the influence of each controller parameter on the system control performance is *** on it,a comparison is made between the disturbance observation ability and anti-disturbance performance of TDOF-LADRC and CLADRC to prove the superiority of TDOF-LADRC in rejecting ***,experiments are performed on a 750 W PMSM experimental platform,and the results demonstrate that the proposed TDOF-LADRC exhibits the properties of two degrees of freedom and improves the disturbance rejection performance of the PMSM system.

关键词： Permanent magnet synchronous motor(PMSM) Active disturbance rejection control(ADRC) Disturbance observer Two-degree-of-freedom control Anti-disturbance

A rare case of hepatic vein-portal vein fistula with hepatolithiasis presenting as cholangiocarcinoma

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 538-540页

作者： Wei li Wen lin le Xiao General Surgery Center The General Hospital of Western Theater CommandChengdu 610083China

To the Editor: We sincerely applaud the work by Tang et al., in which they described caudate lobe-sparing subtotal hepatectomy as treatment for intrahepatic arterioportal fistulas [ 1 ]. Compared to intrahepatic arterioportal fistulas, portal vein-hepatic vein fistulas are rarely reported. Patients typically lack clinical symptoms such as hyperammonemia, cholestatic jaundice, and hypoglycemia, unless the shunt becomes relatively large [ 2, 3 ]. Herein, we describe partial hepatectomy as a treatment for cases of left portal vein-middle hepatic vein fistulas.

关键词： hepatic clinical

Building a More Sustainable Chinese Loess Plateau

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Journal of Earth Science 2024年第1期35卷 283-287页

作者： Peiyue li Xiaomei Kou Yong Wang le Niu School of Water and Environment Chang'an UniversityXi'an 710054China Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the Ministry of Education Chang'an UniversityXi'an 710054China Key Laboratory of Eco-Hydrology and Water Security in Arid and Semi-Arid Regions of the Ministry of Water Resources Chang'an UniversityXi'an 710054China PowerChina Northwest Engineering Corporation limited Xi'an 710065China PowerChina Sinohydro Bureau 3 Co. LTD.Xi'an 710024China

The Chinese Loess Plateau,a region of remarka.le ecological and economic value,grapples with significant water management challenges due to its distinctive geology and *** perspective offers a short review of the eco-environmental protection measures undertaken in the Loess Plateau,underscoring the transformative impacts of initiatives such as the“Grain for Green”***,it also highlights the enduring challenges,including land degradation,water resources issues,socio-economic inequities,and the implications of climate ***,water management emerges as a pivotal issue with far-reaching repercussions for soil conservation,biodiversity,and human *** paper concludes by proposing future actions,emphasizing the necessity for policy modifications,novel initiatives,and research to tackle these challenges and foster sustainable development in the Loess *** insights gained from this region could offer invaluable lessons for other regions confronted with similar challenges,thereby contributing to global efforts to mitigate desertification and champion sustainable development.

关键词： Loess Plateau eco-environmental protection water management sustainable development climate change

Molecularly imprinted sensor based on carboxylated carbon nanotubes/Keggin-type polyoxometalates nanocomposite for the detection of furazolidone

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Tungsten 2024年第2期6卷 394-409页

作者： Yu-Lan Huang Bing Zhang Yu-lian li li Wang le Dong Jian li College of Ocean Food and Biological Engineering Jimei UniversityXiamen 361021China College of Oceanology and Food Science Quanzhou Normal UniversityQuanzhou 362000China

Due to its properties of mutagenic,teratogenic,and carcinogenic,the detection of furazolidone(FZD)in aquaculture is of great importance for food safety and human *** this study,molecularly imprinted fi lms modifi ed with carboxylated multi-walled carbon nanotube-phosphomolybdic acid composite were used to fabricate an electrochemical sensor for the determination of *** nanocomposites were characterized using infrared spectroscopy,scanning electron microscopy,energy-dispersive X-ray spectroscopy,and X-ray diff *** electrochemical characteristics of the modifi ed electrodes were examined using electrochemical impedance spectroscopy,cyclic voltammetry,and diff erential pulse *** sensor exhibited exceptional catalytic *** calibration curves were acquired in the concentration range of 6 nmol·L^(−1)to 0.6μmol·L^(−1),with a limit of detection of 3.38 nmol·L^(−1).Additionally,the sensor proved successful in recognizing FZD in shrimp samples with satisfactory recoveries and *** method provides a strategy to construct a molecularly imprinted electrochemical sensing platform using nanomaterials,which has great promise in the field of food safety.

关键词： Phosphomolybdate Furazolidone Polyoxometalates Carboxylated multi-walled carbon nanotube Molecularly imprinted polymers Electrochemical sensor

linearized waveform inversion for vertical transversely isotropic elastic media:Methodology and multi-parameter crosstalk analysis

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Petroleum Science 2024年第1期21卷 252-271页

作者： Ke Chen Lu liu li-Nan Xu Fei Hu Yuan Yang Jia-Hui Zuo le-le Zhang Yang Zhao National Key Laboratory of Petroleum Resources and Engineering Unconventional Petroleum Research InstituteChina University of Petroleum(Beijing)Beijing102249China Aramco Beijing Research Center Aramco AsiaBeijing100102China University of Lausanne LausanneCH-1015Switzerland Bureau of Geophysical Prospecting China National Petroleum CorporationZhuozhou 072750HebeiChina

Seismic migration and inversion are closely related techniques to portray subsurface images and identify hydrocarbon *** migration aims at obtaining structural images of subsurface geologic *** specifically,seismic migration estimates the reflectivity function(stacked average reflectivity or pre-stack angle-dependent reflectivity)from seismic reflection *** the other hand,seismic inversion quantitatively estimates the intrinsic rock properties of subsurface *** seismic inversion methods are applicable to detect hydrocarbon reservoirs that may exhibit lateral variations in the inverted *** there exist many differences,pre-stack seismic migration is similar with the first iteration of the general linearized seismic ***,seismic migration and inversion techniques assume an acoustic or isotropic elastic *** reservoirs such as shale and tight sand formation have notable anisotropic *** present a linearized waveform inversion(LWI)scheme for weakly anisotropic elastic media with vertical transversely isotropic(VTI)*** is based on two-way anisotropic elastic wave equation and simultaneously inverts for the localized perturbations(ΔVp_(0)/Vp_(0)/Vs_(0)/Vs_(0)/,Δ∈,Δδ)from the long-wavelength reference *** proposed VTI-elastic LWI is an iterative method that requires a forward and an adjoint operator acting on vectors in each *** derive the forward Born approximation operator by perturbation theory and adjoint operator via adjoint-state *** inversion has improved the quality of the images and reduces the multi-parameter crosstalk comparing with the adjoint-based *** have observed that the multi-parameter crosstalk problem is more prominent in the inversion images for Thomsen anisotropy ***,the Thomsen parameter is the most difficult to *** also analyze the multi-parameter crosstalk using scattering radiation patte

关键词： Elastic Anisotropy least-squares imaging Waveform inversion Computational geophysics

Performance Design of High-Temperature Chloride Salts as Thermal Energy Storage Material

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Journal of Thermal Science 2024年第2期33卷 479-490页

作者： ZHAO le WANG Jingyao CUI liu li Baorang DU Xiaoze WU Hongwei Key Laboratory of Power Station Energy Transfer Conversion and System(North China Electric Power University) Ministry of EducationBeijing102206China School of Energy and Power Engineering Lanzhou University of TechnologyLanzhou730050China School of Physics Engineering and Computer ScienceUniversity of HertfordshireHatfieldAL109ABUK

The chloride salts have great potential used as high-temperature thermal energy storage(TES) medium for the concentrated solar power *** this study,liCl,KCl and CaCl_(2) were selected as energy storage materials in order to further broaden the working temperature of ternary chloride salt and improve its energy storage *** new high-temperature energy storage ternary chloride composed of liCl,KCl,and CaCl_(2) was developed based on the phase diagram generated by *** components of liCl-KCl-CaCl_(2) with the mass ratio of 37.85%-53.38%-8.77%,30.90%-13.82%-55.28% and 1.78%-18.61%-79.61% were developed,of which the corresponding melting temperature(T_(m)) 340.93,433.57 and 626.85℃,respectively,was obtained *** that T_(m) of the third group of salts was too high,only the first two groups of salts were *** test showed that the actual melting point was only 0.46% and 1.64% different from the melting point predicted by *** thermal properties of the two ternary chloride salts were also *** solid and liquid-specific heat of ternary salts was determined by DSC using sapphire as the standard *** vapor pressure and decomposition temperature of ternary chloride salts were *** results showed that the vapor pressure of salt 1 was almost constant below 650℃ by ***,the TG results showed that the upper working temperature of salt 1 was 650℃ under the air *** addition,the ternary chloride salts after short-term cycling still exhibited excellent thermal properties,which revealed that these good thermal properties make them have broad application prospects in high-temperature thermal energy storage systems.

关键词： chloride salts thermal energy storages thermal properties thermal stability