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Radiation belt electron wisp inside South Atlantic Anomaly due to terrestrial VLF transmitter observed by MSS-1

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Science China Earth Sciences 2025年第2期68卷 538-548页

作者： Yixin SUN Ying liu Qiugang ZONG Yixin HAO hong ZOU Yuguang ye Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China State Key Laboratory of Lunar and Planetary Science Macao University of Science and TechnologyMacao 999078China Max Planck Institute for Solar System Research Goettingen 37077Germany

The South Atlantic Anomaly represents a region within near-Earth space characterized by a significantly weaker geomagnetic field and a higher flux of energetic particles compared to other areas. It is a space weather hazards to Low-EarthOrbit satellites. There has been evidence that the Very Low Frequency(VLF) waves from the powerful ground VLF radio transmitter in Australia, known as NWC, have the capacity to scatter energetic electrons' pitch angle in the inner radiation *** scattering directs electrons into the drift loss cone, forms a “wisp”, characterized by its peak intensity outside the South Atlantic Anomaly(SAA), and a “rift” exhibiting minimal intensity within SAA. Our findings mark the initial observation of a“wisp” precipitation, an unusual occurrence with peak intensity detected inside the SAA, observed via the Macao Science Satellite-1. Enabled by the Medium-energy Electron Spectrometer onboard Macao Science Satellite-1, we were able to comprehensively measure the full pitch angle distribution at Low-Earth-Orbit. This allowed us to attribute the “wisp” within the anomaly to a specific pitch angle range just outside the drift loss cone, a measurement unattainable by previous satellites. This“wisp” occurrence aligns with previous model predictions, despite being overlooked. Moreover, we distinguished between the trapped and precipitating electron populations. Directly derived from the ratio of these populations, our analysis revealed that approximately 2%-5% of trapped electrons will be lost in this specific wisp due to the influence of the ground VLF *** results not only complement existing evidence of energetic electron pitch angle scattering facilitated by the ground VLF transmitter but also offer a quantitative estimation of its impact.

关键词： South Atlantic Anomaly Radiation belts Electrons precipitation VLF transmitter Wave-particle interaction

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Simulations of electron zebra stripes in the inner radiation belt using a composite empirical electric field model

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Science China Earth Sciences 2025年第1期68卷 27-38页

作者： Ziyang WANG Ying liu Qiugang ZONG hong ZOU Yuguang ye Xuzhi ZHOU Chao YUE Shan WANG Institute of Space Physics and Applied Technology Peking UniversityBeijing100871China State Key Laboratory of Lunar and Planetary Science Macao University of Science and TechnologyMacao999078China

The phenomenon termed“zebra stripes”manifests as regular patterns in the energy-space(L shell)spectrum of energetic electrons(ranging from tens to hundreds ke V)within the inner radiation *** structures exhibit drift-periodic behavior and commonly arise from large-scale electric field perturbations near the substorm *** this study,we introduce a composite electric field model and replicate the formation,structure,and evolution of zebra stripes using a bounce-averaged test particle code under this electric field ***-resolution measurements of energetic electrons obtained from the Van Allen Probes and the recently launched Macao Science Satellites-1 are used as initial conditions and served to validate our test particle *** analyses between observed data and simulations demonstrate our test particle method's efficacy in capturing zebra stripes'general ***,the composite model proves capable of reproducing realistic variations in the electric field within the inner radiation belt to a certain ***,subtle differences emerge in the flux strength and the positions of *** disparities primarily stem from limitations inherent in the electric field model and the initial conditions of the *** that the model represents an average case,it is conceivable that real-world scenarios may deviate from the average,thereby introducing variations in the observed phenomena.

关键词： Zebra stripes Inner radiation belt Large-scale electric fields Van Allen Probes Macao Science Satellite

Foliar-applied zinc promotes cadmium allocation from leaf surfaces to grains in rice

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Journal of Environmental Sciences 2025年第5期151卷 582-593页

作者： Ya-Ting liu Bo-Fang Yan Xuan Cai hong-Xiang Zheng Rong-Liang Qiu ye-Tao Tang School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou 510006China Institute of Facility Agriculture Guangdong Academy of Agricultural SciencesGuangzhou 510640China Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology Sun Yat-sen UniversityGuangzhou 510006China Guangdong Provincial Key Laboratory of Agricultural&Rural Pollution Abatement and Environmental Safety College of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642China

The accumulation of Cd by rice poses significant health *** fertilizationwith Zn can reduce grain Cd contents in rice grown in Cd-contaminated ***,atmospheric deposition on leaves is another vector of Cd contamination,and it remains unclear how Zn application affects the allocation of such *** conducted an experiment where the flag leaves of rice plants were treated with solutions with various Zn concentrations and a constant Cd *** 111Cd stable isotope was used to trace the flux of foliarapplied *** levels of foliar-applied Zn enhanced Cd efflux and grain *** is attributed to limited sequestration of foliar-applied Cd in the leaf cell symplasm and increased Cd desorption from leaf cell walls when a high Zn^(2+)concentration occurs in the *** Zn oxide nanoparticlesmitigated these ***,the expressions of OsLCT1 and OsZIP7 in flag leaves and OsHMA2 and OsZIP7 in the uppermost nodes were upregulated under high-Zn^(2+)treatment,which may facilitate Cd phloem loading and grain *** is advised in using foliar Zn in areas with high atmospheric Cd due to potential grain-contamination risks.

关键词： Atmospheric deposition Isotope labelling Metal interaction Phloem Cell wall

Iron scrap derived nano zero-valent iron/biochar activated persulfate for p-arsanilic acid decontamination with coexisting microplastics

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Journal of Environmental Sciences 2025年第5期151卷 733-746页

作者： Zihan Shu Hailan Yang Shujing ye hong Li Zhiming Yang Chuang Li Xiaofei Tan Shaobo liu Hou Wang College of Environmental Science and Engineering Hunan University and Key Laboratory of Environmental Biology and Pollution Control(Hunan University)Ministry of EducationChangsha 410082China Shenzhen Research Institute of Hunan University Shenzhen 518055China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China College of Resources and Environment University of Chinese Academy of SciencesBeijing 101408China School of Architecture and Art Central South UniversityChangsha 410083China School of Metallurgy and Environment Central South UniversityChangsha 410083China

P-arsanilic acid(AA)has received widespread attention because of its conversion to more toxic inorganic arsenic compounds(arsenate and arsenite)in the natural *** removal process and mechanisms with co-existence of microplastics remain *** this study,biochar loaded with nano zero-valent iron(nZVI)particles(ISBC)was prepared by using iron scrap obtained from a steel works and wood chips collected from a wood processing *** advanced oxidation system of sodium persulfate(PDS)activated by ISBC was applied for AA degradation and inorganic arsenic control in aqueous *** than 99%of the AA was completely degraded by the ISBC/PDS system,and the As(III)on AA was almost completely oxidized to As(V)and finally removed by ***_(3)−inhibited the removal of AA by the ISBC/PDS system,while Cl^(−)had a dual effect that showing inhibition at low concentrations yet promotion at high *** effect of microplastics on the degradation of AA by the ISBC/PDS system was further investigated due to the potential for combined microplastic and organic arsenic contamination in rural/remote *** were found to have little effect on AA degradation in the ISBC/PDS system,while affect the transport of inorganic arsenic generated from AA ***,this study provides new insights and methods for efficient removal of p-arsanilic acid from water with coexisting microplastics.

关键词： P-arsanilic acid Biochar Arsenate and arsenite Microplastics

Overexpression of low-density lipoprotein receptor prevents neurotoxic polarization of astrocytes via inhibiting NLRP3 inflammasome activation in experimental ischemic stroke

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Neural Regeneration Research 2025年第2期20卷 491-502页

作者： Shuai Feng Juanji Li Tingting liu Shiqi Huang Xiangliang Chen Shen liu Junshan Zhou hongdong Zhao ye hong Department of Neurology Nanjing First HospitalNanjing Medical UniversityNanjingJiangsu ProvinceChina Department of Neurology Nanjing Jinling HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsu ProvinceChina

Neurotoxic astrocytes are a promising therapeutic target for the attenuation of cerebral ischemia/reperfusion ***-density lipoprotein receptor,a classic cholesterol regulatory receptor,has been found to inhibit NLR family pyrin domain containing protein 3(NLRP3)inflammasome activation in neurons following ischemic stroke and to suppress the activation of microglia and astrocytes in individuals with Alzheimer’s ***,little is known about the effects of low-density lipoprotein receptor on astrocytic activation in ischemic *** address this issue in the present study,we examined the mechanisms by which low-density lipoprotein receptor regulates astrocytic polarization in ischemic stroke ***,we examined low-density lipoprotein receptor expression in astrocytes via immunofluorescence staining and western blotting *** observed significant downregulation of low-density lipoprotein receptor following middle cerebral artery occlusion reperfusion and oxygen-glucose deprivation/***,we induced the astrocyte-specific overexpression of low-density lipoprotein receptor using astrocyte-specific adeno-associated ***-density lipoprotein receptor overexpression in astrocytes improved neurological outcomes in middle cerebral artery occlusion mice and reversed neurotoxic astrocytes to create a neuroprotective ***,we found that the overexpression of low-density lipoprotein receptor inhibited NLRP3 inflammasome activation in oxygen-glucose deprivation/reoxygenation injured astrocytes and that the addition of nigericin,an NLRP3 agonist,restored the neurotoxic astrocyte *** findings suggest that low-density lipoprotein receptor could inhibit the NLRP3-meidiated neurotoxic polarization of astrocytes and that increasing low-density lipoprotein receptor in astrocytes might represent a novel strategy for treating cerebral ischemic stroke.

关键词： inflammation ischemia/reperfusion injury ischemic stroke low-density lipoprotein receptor neuroprotective astrocytes neurotoxic astrocytes NLRP3 inflammasome polarization

Three-dimensional fracture of UO_(2)ceramic pellets by phase field modeling

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 165-176页

作者： Wei Xiong Xuan ye hongzhang Cheng Xiaoming liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy TechnologyKey Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing 100084China State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Fracture is the primary failure type for the UO_(2)ceramic pellets,which are operated under irradiation and thermal processes,and physically confined by the *** this work,by combining closely coupled physical processes of heat conduction,heat transfer,and mechanical deformation with the cohesive phase field framework,we proposed a high-precision modeling of quasistatic cracking of three-dimensional(3D)UO_(2)ceramic fuel pellets under high temperature and *** simulation results agree well with the experimental results,indicating that the proposed method has the potential to capture 3D crack modes in the interested time ***,we studied the relation of the 3D fracture patterns of fuel pellets with the peak power *** was found that the power level plays a critical role in determining the competition between radial and circumferential cracks,as well as transverse penetrating cracks.

关键词： phase field method nuclear fuel pellet coupled thermo-mechanical model thermal fracture

Metrological traceable calibration of organic carbon and elemental carbon based on laboratory-generated reference materials

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Journal of Environmental Sciences 2025年第3期149卷 524-534页

作者： Yue liu Junjie liu Ji Xiao Jing ye Lixu Guo Caiqing Yan Center for Environmental Metrology National Institute of Metrology ChinaBeijing 100029China College of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan 030024China Environment Research Institute Shandong UniversityQingdao 266237China

Carbonaceous aerosol,including organic carbon(OC)and elemental carbon(EC),has significant influence on human health,air quality and climate *** measurement of carbonaceous aerosol is essential to reduce the uncertainty of radiative forcing estimation and source *** accurate separation of OC and EC is controversial due to the charring of ***,the development of reference materials(RM)for the validation of OC/EC separation is an important basis for further *** RMs were mainly based on ambient air sampling,which could not provide traceability of OC and EC *** develop traceable RMs with known OC/EC contents,our study applied an improved aerosol generation and mixing technique,providing uniform deposition of particles on quartz *** generate OC aerosol with similar pyrolytic property of ambient aerosol,both water soluble organic carbon(WSOC)and water insoluble organic carbon(WIOC)were used,and amorphous carbon was selected for EC *** RMs were analyzed using different *** homogeneity within the filter was validated,reaching below 2%.The long-term stability of RMs has been validated with RSD ranged from 1.7%–3.2%.Good correlationwas observed between nominal concentration of RMswithmeasured concentration by two protocols,while the difference of EC concentration was within 20%.The results indicated that the newly developed RMs were acceptable for the calibration of OC and EC,which could improve the accuracy of carbonaceous aerosol ***,the laboratory-generated EC-RMs could be suitable for the calibration of equivalent BC concentration by Aethalometers.

关键词： Carbonaceous aerosol Split point Reference material Laboratory-generated Traceability

Confined electric field in nano-sized channels of ionic porous framework towards unique adsorption selectivity

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Chinese Chemical Letters 2025年第02期36卷 465-469页

作者： Congyan liu Xueyao Zhou Fei ye Bin Jiang Bo liu School of Chemistry and Materials Science University of Science and Technology of China

Efficient selective adsorption and separation using porous frameworks are critical in many industrial processes,where adsorption energy and dynamic diffusion rate are predominant factors governing *** are highly susceptible to framework charge,which plays a significant role in selective ***,ionic porous frameworks can be divided into two *** of them is composed of a charged backbone and counter *** framework with zwitterionic channels is another *** is composed of regular and alternating arrangements of cationic and anionic building ***,we report a hydrogen-bonded ionic framework （HIF） of{（CN3H6）2[Ti（μ2–O）(SO4)2]}_nwith 1D channel exhibits unique adsorption selectivity for Ar against N2and *** functional theory （DFT） results suggest that CO2cannot be adsorbed by HIF at the experimental temperature due to a positive adsorption free *** addition,due to a relatively large diffusion barrier at 77 K,N2molecules hardly diffuse in HIF channels,while Ar has a negligible diffusion *** unique net positively-charged space in the channel is the key to the unusual phenomena,based on DFT simulations and structural *** findings in this work proposes the new adsorption mechanism and provides unique perspective for special separation applications,such as isotope and noble gasses separations.

关键词： Adsorption Channel Guanidinium Positive electric field Selectivity

Insight into catalytic performance and reaction mechanism for toluene total oxidation over Cu-Ce supported catalyst

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Journal of Environmental Sciences 2025年第3期149卷 476-487页

作者： Xuan Liang Jin Zhang Juntai Tian Zenghua Xie Yue liu Peng liu Daiqi ye School of Environment and Energy South China University of TechnologyGuangzhou 510006China National Engineering Laboratory for VOCs Pollution Control Technology and Equipment Guangzhou 510006China Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control South China University of TechnologyGuangzhou 510006China Guangdong Provincial Engineering and Technology Research Centre for Environmental Risk Prevention and Emergency Disposal South China University of TechnologyGuangzhou 510006China

Herein,three supported catalysts,CuO/Al_(2)O_(3),CeO_(2)/Al_(2)O_(3),and CuO-CeO_(2)/Al_(2)O_(3),were synthesized by the convenient impregnation method to reveal the effect of CeO_(2)addition on catalytic performance and reaction mechanism for toluene *** with CuO/Al_(2)O_(3),the T_(50)and T_(90)(the temperatures at 50%and 90%toluene conversion,respectively)of CuO-CeO_(2)/Al_(2)O_(3)were reduced by 33 and 39°C,respectively.N_(2)adsorptiondesorption experiment,XRD,SEM,EDS mapping,Raman,EPR,H_(2)-TPR,O_(2)-TPD,XPS,NH_(3)-TPD,Toluene-TPD,and in-situ DRIFTS were conducted to characterize these *** excellent catalytic performance of CuO-CeO_(2)/Al_(2)O_(3)could be attributed to its strong coppercerium interaction and high oxygen vacancies ***,in-situ DRIFTS proved that CuO-CeO_(2)/Al_(2)O_(3)promoted the conversion of toluene to benzoate and accelerated the deep degradation path of *** work provided valuable insights into the development of efficient and economical catalysts for volatile organic compounds.

关键词： Cu-Ce supported catalyst Copper-cerium interaction Oxygen vacancies Toluene oxidation Reaction mechanism