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research in Astronomy and Astrophysics 2025年第1期25卷 240-248页

作者： Yuhang Gao Hui Tian Tom Van Doorsselaere Zihao Yang Mingzhe Guo Konstantinos Karampelas School of Earth and Space Sciences Peking University Centre for Mathematical Plasma Astrophysics Department of MathematicsKU Leuven high altitude Observatory National Center for Atmospheric Research Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong University

Recent observations have demonstrated the capability of mapping the solar coronal magnetic field using the technique of coronal seismology based on the ubiquitous propagating Alfvénic/kink waves through imaging *** established a magnetohydrodynamic model of a gravitationally stratified open magnetic flux tube,exciting kink waves propagating upwards along the *** modeling was performed to synthesize the Fe XIII 1074.7 and 1079.8 nm spectral line profiles,which were then used to determine the wave phase speed,plasma density,and magnetic field with seismology method.A comparison between the seismologically inferred results and the corresponding input values verifies the reliability of the seismology *** addition,we also identified some factors that could lead to errors during magnetic field *** results may serve as a valuable reference for current and future coronal magnetic field measurements based on observations of propagating kink waves.

关键词： magnetohydrodynamics (MHD) Sun: corona Sun: magnetic fields

Phenanthrene perturbs hematopoietic development and causes hematopoietic defects in zebrafish

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Journal of Environmental Sciences 2025年第5期151卷 573-581页

作者： Lingyu Ren Yue Wang Ying Ren Guangke Li Nan Sang College of Environment and Resource Research Center of Environment and HealthShanxi UniversityTaiyuan 030006China

Phenanthrene(Phe)is one of the common polycyclic aromatic hydrocarbons in the environment,and recent studies show that it can cause cardiac developmental toxicity and ***,it is still unknown whether it can affect the hematopoietic development in aquatic *** address this question,zebrafish(Danio rerio)were chronically exposed to Phe at different *** found that Phe caused structural damage to the renal tubules in the kidney,induced malformed erythrocytes in peripheral blood,and decreased the proportion of myeloid cells in adult zebrafish,suggesting possible negative impacts that Phe posed to hematopoietic ***,using in situ hybridization technology,we found that Phe decreased the expression of primitive hematopoietic marker genes,specifically gata1 and pu.1,accompanied by an obstruction of primitive erythrocyte ***,Phe impaired definitive hematopoiesis,increased aberrations of the transient hematopoietic site(PBI),and reduced the generation of hematopoietic stem cells,ultimately influencing the number of erythrocytes and myeloid *** findings suggested that Phe could induce hematopoietic toxicity in zebrafish embryos and pose unknown ecological risks.

关键词： Phenanthrene Zebrafish Hematopoietic development Hematopoietic defect

Managing virus diseases in citrus:Leveraging high-throughput sequencing for versatile applications

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Horticultural Plant Journal 2025年第1期11卷 57-68页

作者： Hongming Chen Zhiyou Xuan Lu Yang Song Zhang Mengji Cao Integrative Science center of Germplasm Creation in Western China(Chongqing)Science City Citrus Research InstituteSouthwest UniversityChongqing 400712China National Citrus Engineering research center Citrus Research InstituteSouthwest UniversityChongqing 400712China

In this review,the advantages and advances in applying high-throughput sequencing(HTS)in the management of viral diseases in citrus,along with some challenges,are discussed to provide perspectives on future *** the initial implementation of HTS in citrus virology,a substantial number of citrus viruses have been identified,with a notable increase in the last 7 *** acquisition of viral genomes and various HTS-based omics analyses serve as crucial pillars for advancing research in the etiology,epidemiology,pathology,evolution,ecology,and biotechnology of citrus *** has notably contributed to disease diagnosis,such as the diagnoses of concave gum and impietratura,as well as to the surveillance of new virus risks and the preparation of virus-free ***,certain inherent defects in HTS and coupled bioinformatics analysis,such as challenges with sequence assembly and the detection of viral dark matter,require improvement to enhance practical *** addition,the utilization of HTS for the systematic management of citrus viral diseases remains limited,and drawing insights from other virus-plant pathosystems while integrating emerging compatible techniques and ideas may broaden its specific applications.

关键词： Deep sequencing Virus epidemics Functional genomics CRISPR/Cas Virus-host interactions

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Synthesis of intermetallic PtCo fuel cell catalysts from bimetallic core@shell structured nanoparticles

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Journal of Energy Chemistry 2025年第2期101卷 1-6页

作者： Le Zhang Lei Tong Shuai Li Chang-Song Ma Kun-Ze Xue Hai-Wei Liang Hefei National research center for Physical Sciences at the Microscale Department of Chemistry University of Science and Technology of China

The high activity and stability of intermetallic PtCo nanocatalysts toward oxygen reduction reaction make them a top candidate as low-Pt cathode catalysts in proton exchange membrane fuel cells（PEMFCs）.However,forming intermetallic structures typically requires high-temperature annealing,posing a challenge for achieving well-size control and highly ordered *** we report the design and synthesis of bimetallic co re@shell structured precursors for affording high-performance intermetallic PtCo *** fabrication of the core@shell precursor involves using a molecular ligand containing both sulfur and oxygen donors to selectively bind with Pt colloidal nanoparticles as the core and chelate Co ions as the *** high-temperature annealing,the ligand transforms into carbon coatings around alloy nanoparticles,preventing particle sintering;meanwhile,Co ions in the shell can easily diffuse into the Pt core,which helps to increase the thermodynamic driving force for forming intermetallic *** benefits enable us to obtain the catalyst with finely dispersed nanoparticles（～3.5 nm）and a high ordering degree of 72%.With 0.1 mgPt/cm2cathode loading,the catalyst delivers superior performance and durability in PEMFCs,showing an initial mass activity of 0.56 A/mgPt,an initial power density of 1.05 W/cm2at 0.67 V（H2-air）,and a voltage loss of 26 mV at 0.8 A/cm2after the accelerated durability test.

关键词： Bimetallic structure Fuel cells Intermetallic PtCo Oxygen reduction reaction

Facilitated water dissociation by coupling bimetallic phosphide with manganese oxide to enhance alkaline hydrogen evolution

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Nano research 2025年第2期18卷 184-192页

作者： Xiaolan Tang Na Yang Zixiao Li Xun He Qiuying Dai Hefeng Wang Yongchao Yao Yujie Yuan Hong Tang Dongdong Zheng Shengjun Sun Asmaa Farouk Mohamed S.Hamdy Xiaobin Niu Tingshuai Li Xuping Sun Bo Tang School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China College of Chemistry Chemical Engineering and Materials ScienceShandong Normal UniversityJinan 250014China center for high altitude Medicine West China HospitalSichuan UniversityChengdu 610041China Department of Chemistry College of ScienceKing Khalid UniversityP.O.Box 900461413 AbhaSaudi Arabia Laoshan Laboratory Qingdao 266237China

Fabricating catalysts with efficient water dissociation and robust stability is key to advancing the industrialization of the alkaline hydrogen evolution reaction(HER).Establishing an effective phosphide/oxide interface is a feasible way to improve the HER performance of the catalyst in an alkaline medium,but it remains ***,we adopt that manganese oxide nanoparticles decorated on nickel-cobalt phosphide nanowire array on nickel foam(MnO_(x)@NiCoP/NF)via a surface modification strategy that shifts the d-band center downward,promoting the water dissociation and hydrogen intermediate ***,MnO_(x) makes the surface of NiCoP rougher,facilitating bubble release and improving the array ***,MnO_(x)@NiCoP/NF achieves industrial current densities of 500 and 1000 mA·cm^(-2) with overpotentials of 171 and 193 mV,respectively,while maintaining stable operation for over 600 h at 1000 mA·cm^(-2) in 1 M ***,an anion exchange membrane electrolyzer with the catalyst was fabricated and shows potential for practical applications.

关键词： manganese oxide bimetallic phosphides heterojunction hydrogen evolution reaction water electrolysis

Field topologies in ideal and near-ideal magnetohydrodynamics and vortex dynamics

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Science China(Physics,Mechanics & Astronomy) 2015年第1期58卷 12-31页

作者： LOW B.C. high altitude Observatory National Center for Atmospheric Research

Magnetic field topology frozen in ideal magnetohydrodynamics （MHD） and its breakage in near-ideal MHD are reviewed in two parts, clarifying and expanding basic concepts. The first part gives a physically complete description of the frozen field topology derived from magnetic flux conservation as the fundamental property, treating four conceptually related topics： Eulerian and La- grangian descriptions of three dimensional （3D） MHD, Chandrasekhar-Kendall and Euler-potential field representations, magnetic helicity, and inviscid vortex dynamics as a fluid system in physical contrast to ideal MHD. A corollary of these developments clar- ifies the challenge of achieving a high degree of the frozen-in condition in numerical MHD. The second part treats field-topology breakage centered around the Parker Magnetostatic Theorem on a general incompatibility of a continuous magnetic field with the dual demand of force-free equilibrium and an arbitrarily prescribed, 3D field topology. Preserving field topology as a global con- straint readily results in formation of tangential magnetic discontinuities, or, equivalently, electric current-sheets of zero thickness. A similar incompatibility is present in the steady force-thermal balance of a heated radiating fluid subject to an anisotropic thermal flux conducted strictly along its frozen-in magnetic field in the low-fl limit. In a weakly resistive fluid the thinning of current sheets by these general incompatibilities inevitably results field notwithstanding the small resistivity. Strong Faraday in sheet dissipation, resistive heating and topological changes in the induction drives but also macroscopically limits this mode of energy dissipation, trapping or storing free energy in self-organized ideal-MHD structures. This property of MHD turbulence captured by the Taylor hypothesis is reviewed in relation to the Sun＇s corona, calling for a basic quantitative description of the breakdown of flux conservation in the low-resistivity li

关键词： magnetic topology magnetic reconnection current sheets magnetic helicity thermal conduction solar corona magnetohy-drodynamics interstellar clouds

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Fault Diagnosis for Railway Point Machines Using VMD Multi-Scale Permutation Entropy and ReliefF Based on Vibration Signals

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Chinese Journal of Electronics 2025年第1期34卷 204-211页

作者： Yongkui Sun Yuan Cao Peng Li Shuai Su National Engineering research center of Rail Transportation Operation and Control System Beijing Jiaotong University School of Automation and Intelligence Beijing Jiaotong University Frontiers Science center for Smart high-speed Railway System Beijing Jiaotong University

The railway point machine plays an important part in railway systems. It is closely related to the safe operation of trains. Considering the advantages of vibration signals on anti-interference, this paper develops a novel vibration signal-based diagnosis approach for railway point machines. First, variational mode decomposition(VMD)is adopted for data preprocessing, which is verified more effective than empirical mode decomposition. Next, multiscale permutation entropy is extracted to characterize the fault features from multiple scales. Then ReliefF is utilized for feature selection, which can greatly decrease the feature dimension and improve the diagnosis accuracy. By experiment comparisons, the proposed approach performs best on diagnosis for railway point machines. The diagnosis accuracies on reverse-normal and normal-reverse processes are respectively 100% and 98.29%.

关键词： Vibrations Fault diagnosis Accuracy Data preprocessing Switches Feature extraction Rail transportation Entropy Maintenance Monitoring

Prediction and optimization of flue pressure in sintering process based on SHAP

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 346-359页

作者： Mingyu Wang Jue Tang Mansheng Chu Quan Shi Zhen Zhang School of Metallurgy Northeastern UniversityShenyang 110819China Liaoning Low-Carbon Steelmaking Technology Engineering research center Northeastern UniversityShenyang 110819China Engineering research center of Frontier Technologies for Low-Carbon Steelmaking(Ministry of Education) Shenyang 110819China

Sinter is the core raw material for blast *** pressure,which is an important state parameter,affects sinter *** this paper,flue pressure prediction and optimization were studied based on the shapley additive explanation(SHAP)to predict the flue pressure and take targeted adjustment ***,the sintering process data were collected and processed.A flue pressure prediction model was then constructed after comparing different feature selection methods and model algorithms using SHAP+extremely random-ized trees(ET).The prediction accuracy of the model within the error range of±0.25 kPa was 92.63%.SHAP analysis was employed to improve the interpretability of the prediction *** effects of various sintering operation parameters on flue pressure,the relation-ship between the numerical range of key operation parameters and flue pressure,the effect of operation parameter combinations on flue pressure,and the prediction process of the flue pressure prediction model on a single sample were analyzed.A flue pressure optimization module was also constructed and analyzed when the prediction satisfied the judgment *** operating parameter combination was then *** flue pressure was increased by 5.87%during the verification process,achieving a good optimization effect.

关键词： sintering process flue pressure shapley additive explanation prediction optimization

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A dry-electrode enabled ECG-on-Chip with arrhythmia-aware data transmission

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Science China(Information Sciences) 2025年第2期68卷 338-353页

作者： Xinzi XU Yanxing SUO Yang ZHAO Peiyi ZHOU Xiao HAN Qiao CAI Min WANG Jiajun YUAN Liebin ZHAO Yongfu LI Guoxing WANG Yong LIAN Department of Micro-Nano Electronics and MoE Key Lab of Artificial Intelligence Shanghai Jiao Tong University Pediatric AI Clinical Application and research center Shanghai Engineering Research Center of Intelligence Pediatrics (SERCIP)Child Health Advocacy InstituteShanghai Children's Medical CenterSchool of MedicineShanghai Jiao Tong University Shanghai Engineering research center of Intelligence Pediatrics (SERCIP) Xin Hua Hospital Affiliate to Shanghai Jiao Tong University School of Medicine

Early detection and treatment of cardiovascular diseases(CVDs) can be significantly enhanced through the use of flexible wearable electrocardiogram(ECG) sensors, potentially reducing CVD-related mortality. This paper introduces an ECG-on-Chip(EoC) solution tailored for flexible ECG sensors, incorporating novel features to address common challenges in wearable ECG technology. The EoC integrates a chopper-stabilized capacitively-coupled instrumentation amplifier(CS-CCIA),ensuring a high common-mode rejection ratio(CMRR) and low noise performance. Performance is further boosted via a positive feedback loop(PFL) and a programmable gain amplifier(PGA) with shared on-chip calibration logic, which enhances input impedance and minimizes gain variability to ensure consistent algorithm performance. Additionally, a secondary chopping technique is employed to further reduce noise, achieving an input-referred noise level of 454 nVrms. The embedded algorithm within the EoC is designed to extract clinically meaningful features, facilitating robust real-time arrhythmia analysis. Fabricated using a 0.18 μm CMOS process, the EoC consumes 14.9 μW with a supply voltage of 1.2 V. The algorithm's efficacy has been validated over 0.4 million heartbeats, demonstrating a sensitivity of over 99.7% for R-peak detection and 98.3% for arrhythmia analysis. To demonstrate practical application, the EoC has been integrated with a commercial Bluetooth low energy(BLE)transceiver, forming a wireless arrhythmia monitoring sensor equipped with dry electrodes. This system consumes 292.04 μW in arrhythmia-aware transmission mode, supporting 13 days of operation with a 30 mAh thin-film battery.

关键词： ECG flexible dry electrodes analog front-end abnormality detection ASIC wireless transmission

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Electrocatalytic selective synthesis and tandem utilization of hydroxylamine

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Science China Chemistry 2025年

作者： Yuxuan Lu Hengquan Yang Engineering research center of Ministry of Education for Fine Chemicals School of Chemistry and Chemical Engineering Shanxi Key Laboratory of Green Catalytic Synthesis of Coal-based High Value Chemicals Shanxi University

The transformation of renewable nitrogen feedstock to nitrogenous chemicals plays a significant role in our modern society,considering the crucial impact of nitrogenous chemicals on life sciences,biomedicine,agriculture,and *** （NH2OH）,a typical nucleophile,has been widely served as the nitrogenous feedstock to produce nitrogenous *** NH2OH synthesis methods rely on harsh reaction conditions,leading to an unfavorable environmental *** contrast,nitric oxide electroreduction promises to produce NH2OH powered by renewable *** achievements have revealed the possibility of this process,but have also identified significant *** activity and selectivity are fundamentally limited by competing hydrogenation reactions,while the performance evaluation with high accuracy and reproducibility is ***,this review aims to provide insight into the mechanism of NH2OH electrosynthesis,especially regarding understanding reaction pathways and the design principle towards efficient ***,the performance evaluation parameters and standard measurement methods for NH2OH synthesis are summarized to screen efficient ***,the prospects and emerging opportunities to synthesize nitrogen-containing organic compounds by tandem reaction are *** review aims to provide a guide for evaluating and exploring efficient electrocatalytic systems for NH2OH production and utilization technology.

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