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Research in Astronomy and Astrophysics 2024年第8期24卷 42-51页

作者： jin-hui rao Shu-Xu Yi Lian Tao Qing-Wen Tang Department of Physics School of Physics and Materials ScienceNanchang UniversityNanchang 330031China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Theories of modified gravity suggest that the propagation speed of gravitational waves(GW)v_gmay deviate from the speed of light c.A constraint can be placed on the difference between c and v_gwith a simple method that uses the arrival time delay between GW and electromagnetic wave simultaneously emitted from a burst *** simulated the joint observation of GW and short gamma-ray burst signals from binary neutron star merger events in different observation campaigns,involving advanced LIGO(aLIGO)in design sensitivity and Einstein Telescope(ET)joint-detected with Fermi/*** a result,the relative precision of constraint on v_gcan reach~10~(-17)(aLIGO)and~10^(-18)(ET),which are one and two orders of magnitude better than that from GW170817,*** continue to obtain the bound of graviton mass m_g≤7.1(3.2)×10~(-20)eV with aLIGO(ET).Applying the Standard-Model Extension test framework,the constraint on v_gallows us to study the Lorentz violation in the nondispersive,nonbirefringent limit of the gravitational *** obtain the constraints of the dimensionless isotropic coefficients S_(00)^(4)at mass dimension d=4,which are-1×10^(-15)

关键词： gravitational waves-(stars)gamma-ray burst general-stars neutron

Ground-layer Adaptive Optics for the 2.5 m Wide-field and High-resolution Solar Telescope

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Research in Astronomy and Astrophysics 2024年第3期24卷 224-236页

作者： Ying Yang Lan-Qiang Zhang Nan-Fei Yan jin-Sheng Yang Zhen Li Teng-Fei Song Xue-Jun rao Chang-hui rao Key Laboratory on Adaptive Optics Chinese Academy of SciencesChengdu 610209China Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China School of Electronic Electrical and Communication Engineering of the University of Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory of Modern A&A Ministry of EducationNanjing 210023China Yunnan Observatories Chinese Academy of SciencesKunming 650216.China

The 2.5 m wide-field and high-resolution solar telescope(WeHoST)is currently under developing for solar *** aims to achieve high-resolution observations over a super-wide field of view(FOV)of5′×5′,and a desired resolution of 0.3″.To meet the scientific requirements of WeHoST,the ground-layer adaptive optics(GLAO)with a specially designed wave front sensing system is as the primary *** introduce the GLAO configuration,particularly the wave front sensing *** analytic method,we simulate the performance of both classical AO and GLAO systems,optimize the wave front sensing system,and evaluate GLAO performance in terms of PSF uniformity and correction improvement across whole *** results indicate that,the classical AO will achieve diffraction-limited resolution;the suggested GLAO configuration will uniformly improve the seeing across the full 5′×5′FOV,reducing the FWHM across the axis FOV to less than0.3″(λ≥705 nm,r0≥11 cm),which is more than two times *** specially designed wave front sensor schedule offers new potential for WeHoST’s GLAO,particularly the multi-FOV GLAO and the flexibility to select the detected *** capabilities will significantly enhance the scientific output of the telescope.

关键词： instrumentation adaptive optics-instrumentation detectors-instrumentation high angular resolution-methods numerical-telescopes-Sun activity

Vibration Suppression for Active Magnetic Bearings Using Adaptive Filter with Iterative Search Algorithm

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 61-71页

作者： jin-hui Ye Dan Shi Yue-Sheng Qi jin-hui Gao Jian-Xin Shen IEEE Department of Electrical Engineering Zhejiang UniversityHangzhou 310027China CES and IEEE

Active Magnetic Bearing(AMB) is a kind of electromagnetic support that makes the rotor movement frictionless and can suppress rotor vibration by controlling the magnetic force. The most common approach to restrain the rotor vibration in AMBs is to adopt a notch filter or adaptive filter in the AMB controller. However, these methods cannot obtain the precise amplitude and phase of the compensation current. Thus, they are not so effective in terms of suppressing the vibrations of the fundamental and other harmonic orders over the whole speed range. To improve the vibration suppression performance of AMBs,an adaptive filter based on Least Mean Square(LMS) is applied to extract the vibration signals from the rotor displacement signal. An Iterative Search Algorithm(ISA) is proposed in this paper to obtain the corresponding relationship between the compensation current and vibration signals. The ISA is responsible for searching the compensating amplitude and shifting phase online for the LMS filter, enabling the AMB controller to generate the corresponding compensation force for vibration suppression. The results of ISA are recorded to suppress vibration using the Look-Up Table(LUT) in variable speed range. Comprehensive simulations and experimental validations are carried out in fixed and variable speed range, and the results demonstrate that by employing the ISA, vibrations of the fundamental and other harmonic orders are suppressed effectively.

关键词： Active Magnetic Bearing(AMB) Adaptive filter Iterative search algorithm Least mean square(LMS) Vibration suppression

Effects of physical properties of supercritical water on heat transfer characteristics of single particle within a particle cluster Author links open overlay panel

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Particuology 2024年第8期91卷 291-302页

作者： Xiaoyu Li Bowei Zhang huibo Wang hui jin State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an710049China

The complex physical properties of supercritical water(SCW)make the heat transfer characteristics of particles within a particle cluster *** heat transfer characteristics of single particle within a particle cluster in SCW,influenced by surrounding particles,have not been effectively *** numerical simulations were conducted to investigate the heat transfer characteristics of particle clusters in SCW under different *** results were compared and analyzed with those from constant property *** was found that Reynolds number(Re)and the void fraction of particle cluster have no special effects on the variation trends of Nusselt number(Nu)for the focused ***,the particle temperature had a significant effect on the variation trends of *** effect of Re on the heat transfer rate exponent(η)of the focused particle can be divided into two zones:a significant effect zone and a non-significant effect *** effect of void fraction onηin the non-significant effect zone was *** the non-significant effect zone,ηdecreased with the increasing particle *** the significant effect zone,the variation trends ofηbecame more *** fundamental reason for this series of phenomena is the changes in distribution of physical properties.A model forηwas developed for the non-significant effect *** model can filter out the effects of Re and certain particle cluster spatial configurations,and it demonstrates good predictive performance.

关键词： Supercritical water Particle cluster Heat transfer characteristics Heat transfer rate exponent Physical properties correction

N-Heterocyclic carbene-catalyzed enantioselective(dynamic) kinetic resolutions and desymmetrizations

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Science China Chemistry 2024年第2期67卷 482-511页

作者： Yi Zhang hui Cai Xiuhai Gan Zhichao jin National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityHuaxi DistrictGuiyang550025China

N-heterocyclic carbene-catalyzed enantioselective kinetic resolutions,dynamic kinetic resolutions,and desymmetrization reactions are systematically *** content is organized according to the activation modes involved i... 详细信息

关键词： N-heterocyclic carbene kinetic resolution dynamic kinetic resolution desymmetrization organocatalysis

Recent progresses in thermal treatment of β-Ga_(2)O_(3) single crystals and devices

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1659-1677页

作者： Yuchao Yan Zhu jin hui Zhang Deren Yang State Key Laboratory of Silicon and Advanced Semiconductor Materials and School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China Zhejiang Provincial Key Laboratory of Power Semiconductor Materials and Devices ZJU-Hangzhou Global Scientific and Technological Innovation CenterHangzhou 311200China

In recent years,ultra-wide bandgap β-Ga_(2)O_(3) has emerged as a fascinating semiconductor material due to its great potential in power and photoelectric *** semiconductor industrial,thermal treatment has been widely utilized as a convenient and effective approach for substrate property modulation and device ***,a thorough summary of β-Ga_(2)O_(3) substrates and devices behaviors after high-temperature treatment should be *** this review,we present the recent advances in modulating properties of β-Ga_(2)O_(3) substrates by thermal treatment,which include three major applications:(ⅰ)tuning surface electrical properties,(ⅱ)modifying surface morphology,and(ⅲ)oxidating ***,regulating electrical contacts and handling with radiation damage and ion implantation have also been discussed in device *** each category,universal annealing conditions were speculated to figure out the corresponding problems,and some unsolved questions were proposed *** review could construct a systematic thermal treatment strategy for various purposes and applications of β-Ga_(2)O_(3).

关键词： β-gallium oxide thermal treatment substrates devices

The new challenges for the development of NH_(3)-SCR catalysts under new situation of energy transition in power generation industry

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Chinese Chemical Letters 2024年第6期35卷 95-103页

作者： Feibin Wei Yongfang rao Yu Huang Wei Wang hui Mei Science and Technology on Thermostructural Composite Materials Laboratory School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Key Laboratory of Aerosol Chemistry and Physics State Key Laboratory of Loess and Quaternary Geology(SKLLQG)Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Center of Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi’an 710061China University of Chinese Academy of Sciences Beijing 100049China Department of Environmental Science and Engineering Xi’an Jiaotong UniversityXi’an 710049China

NH_(3)-SCR was one of the most promising de NO_x technologies and it has been widely applied in industrial NO_x ***,with the further development of energy transformation in power generation sector,the development of NH_(3)-SCR catalysts is facing some new *** is becoming an urgent problem to solve low catalytic activity and stability of NH_(3)-SCR catalysts at the working condition of ultra-low temperature(≤200℃)and high concentrations of H_(2)O+SO_(2) due to the gradual deployment of new energy power ***,the traditional coal-fired power plants would need flexible operation with the increasing share of renewable energy *** NH_(3)-SCR catalysts which were applied in coal-fired power industry would be requested to work in a wide temperature window from 200℃ to 500℃ in the near ***,in this review,we summarized the progress of NH_(3)-SCR catalysts in solving these different industrial problems in recent *** the research directions which were deserved to be focused on the development of NH_(3)-SCR catalysts for the energy transition of power generation sector are proposed.

关键词： NH_(3)-SCR NOx reduction Power generation Ultra-low temperature Wide temperature windows

Rapid synthesis of oxygen-defected molybdenum oxides quantum dots as efficient nanozymes for healing diabetic ulcers

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Nano Research 2024年第7期17卷 6376-6385页

作者： Fangjun Cao hui Feng Jiaxin Yao Xiang Hou Tiezhi jin Junfeng hui Shaanxi Key Laboratory of Qinling Ecological Security Shaanxi Institute of ZoologyXi’an 710072China Engineering Research Center of Western Resource Innovation Medicine Green Manufacturing Ministry of EducationSchool of Chemical EngineeringNorthwest UniversityXi'an 710069China Shaanxi Key Laboratory of Degradable Biomedical Materials and Shaanxi R&D Center of Biomaterials and Fermentation Engineering School of Chemical EngineeringNorthwest UniversityXi'an 710069China

The continuous inflammatory response in diabetic skin wounds leads to excessive production of reactive oxygen species,which cause a vicious circle of long-term *** the therapeutic research of metal nanoenzymes for healing diabetic ulcers,it still faces the challenges in poor nanoenzymes activity and low-efficient therapeutic ***,ultrasmall oxygen-deficient MoO_(3−X)quantum dots were fabricated and employed as nanoenzymes for healing fiabetic *** PEGylation,PEGylated MoO_(3−X)quantum dots(MoO_(3−X)/PEG)with oxygen vacancies exhibits excellent photothermal,peroxidase/catalase-like *** addition,these MoO_(3−X)/PEG showed superior properties in scavenging H_(2)O_(2)and effectively inhibiting the scavenging of reactive oxygen *** importantly,such an oxygen-defected MoO_(3−X)/PEG had obvious antibacterial and skin repairing effects on alleviating hypoxia and excessive oxidative stress even in a mouse model of diabetic ulcers,inhibiting proinflammatory cytokines and significantly accelerating the healing of infected wounds,which shows great application potential for promoting wound *** work highlights that the developed oxygen defected molybdenum oxide compounds capable of peroxidaselike and catalase-like activities show great application potential for healing diabetes wound.

关键词： oxygen-defected molybdenum-based nanoenzymes antioxidant anti-inflammatory diabetes ulcer wounds

Hierarchical V_(3)S_(4)/C nanofibers with fast kinetics for superior alkali metal batteries

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Rare Metals 2024年第4期43卷 1836-1844页

作者： Li Chen Zhi-Xin rao Zhi Chen Zhao-hui Wu Shuai Yang Zhi-Jun Feng hui-Yong Yang Fan-Yan Zeng Xi-Bao Li jin-Yang Hu Jun-Tong Huang School of Materials Science and Engineering Nanchang Hangkong UniversityNanchang330063China School of Aeronautical Manufacturing Engineering Nanchang Hangkong UniversityNanchang330063China

Owing to the numerous benefits,including low cost and great theoretical capacity,V3S4 has been a research hotspot for Li^(+)/Na^(+)/K^(+) ***,the V_(3)S_(4) electrode with long cycling stability and high specific capacities continues to pose significant *** this work,vacuum vulcanization is combined with electrospinning to synthesize V_(3)S_(4)/C composite nanofibers(V_(3)S_(4)@CNF).

关键词： composite fibers kinetics

Influence of crystal-transforming agent on the performance and mechanism ofα-high-strength gypsum prepared from FGD gypsum

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Particuology 2024年第4期87卷 37-45页

作者： Zhuoyue Xu Xiao Wang Biao jin Dawang Zhang hui Li College of Materials Science and Engineering Xi'an University of Architecture and TechnologyXi'an710055China Schoolof Materials and Chemical Engineering Henan University of Urban ConstructionPingdingshan46736China

This paper investigates the impact of flue gas desulfurization(FGD)gypsum's crystal modifier on the characteristics and microcosmic mechanism ofα-high strength *** results demonstrate that all three crystal modifiers can convert FGD gypsum toα-high-strength *** acid(CA)has the most significant influence onα-high-strength gypsum,and the preparedα-high-strength gypsum is short columnar,with an aspect ratio in the range of 1-3,and has a faster setting time,a larger specific surface area,and a smaller standard consistency,higher compressive strength,greater surface hardness,and smaller crystal particle *** initial setting time of theα-high-strength gypsum manufactured with CA crystal modifier was decreased by 36%compared to the blank sample,the final setting time was lowered by 37.5%,and the water consumption of the standard consistency was reduced by 8%.The maximum strength is 32 MPa after 2 h,the absolute dry compressive strength is up to 38 MPa,and the surface hardness is improved by 24.43%.

关键词： Flue gas desulfurization gypsum Crystal modifier Microscopic mechanism α-high-strength gypsum