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Effects of photo-oxidation and transition metals on the formation of reactive oxygen species from aromatic compounds using spectroscopic method

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Journal of Environmental sciences 2025年第5期151卷 1-11页

作者： Xiaoyu Hu Juanjuan Qin Yuanyuan Qin Tianyi Zhao Yuxuan Cao Qinghe Cai Lijia Zhang Yang Zhang College of Resources and Environment University of Chinese Academy of SciencesBeijing 101408China Beijing Yanshan earth Critical Zone National Research Station Beijing 101408China Resource and Environmental Branch China National Institute of StandardizationHaidian DistrictBeijing 100191China Binzhou Institute of Technology Binzhou 256606China

Particulate matter(PM)can cause adverse health effects by overproducing reactive oxygen species(ROS).Although the ability of PM to induce ROS generation depends on its composi-tion and environmental *** study explores how photo-oxidation affects ROS gen-eration from aromatic compounds(ACs,including catechol(CAT),phthalic acid(PA),and 4,4-oxydibenzoic acid(4,4-OBA))and their mixtures with transition metals(TMs,includ-ing Fe(II),Mn(II),and Cu(II))using Fourier-transform infrared(FTIR)and Ultraviolet-visible spectroscopy(UV-Vis).Results showed that photo-oxidation facilitated ROS generation from ***-Fe(II)/Cu(II)showed synergistic effects,but 4,4-OBA-Fe(II)/Cu(II)showed antag-onistic ***-Mn(II)and PA-Fe(II)/Cu(II)exhibited synergistic effects first and then showed antagonistic *** different interactions were due to complexation between ACs and *** photo-oxidized ACs-TMs significantly enhanced ROS generation com-pared with *** study suggested the photo-oxidation mechanism involved that the transfer ofπ-electrons from the ground to an excited state in benzene rings and func-tional groups,leading to the breakage and formation of chemical bonds or easierπ-electron transfer from ACs to *** former could generate ROS directly or produce polymers that promoted ROS generation,while the latter promoted ROS generation by transferringπ-electrons to dissolved oxygen *** study revealed that both interactions among components and photo-oxidation significantly influenced ROS *** studies should integrate broader atmospheric factors and PM components to fully assess oxidative potential and health impacts.

关键词： Reactive oxygen species Aromatic compounds Transitional metals Photo-oxidation

Subduction tectonics *** tectonics——Discussion on driving forces for plate motion

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science China earth sciences 2020年第3期63卷 315-328页

作者： Ling CHEN Xu WANG Xiaofeng LIANG Bo WAN Lijun LIU State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China CAS Center for Excellence in Tibetan Plateau earth sciences Beijing 100101China University of Chinese academy of sciences Beijing 100049China innova tion academy for earth science Chinese Academy of SciencesBeijing 100029China Department of Geology University of Illinois at Urbana-ChampaignChampaign 61820USA

Plate tectonics describes the horizontal motions of lithospheric plates,the earths outer shell,and interactions among them across the earths *** the establishment of the theory of plate tectonics about half a century ago,considerable debates have remained regarding the driving forces for plate *** early"Bottom up"view,i.e.,the convecting mantledriven mechanism,states that mantle plumes originating from the core-mantle boundary act at the base of plates,accelerating continental breakup and driving plate *** the present,however,the"Top down"idea is more widely accepted,according to which the negative buoyancy of oceanic plates is the dominant driving force for plate motion,and the subducting slabs control surface tectonics and mantle *** this regard,plate tectonics is also known as subduction tectonics."Top down"tectonics has received wide supports from numerous geological and geophysical *** the other hand,recent studies indicate that the acceleration/deceleration of individual plates over the million-year timescale may reflect the effects of mantle *** is also suggested that surface uplift and subsidence within stable cratonic areas are correlated with plumerelated magmatic activities over the hundred-million-year *** the global scale,the cyclical supercontinent assembly and breakup seem to be coupled with superplume activities during the past two billion *** correlations over various spatial and temporal scales indicate the close relationship and intensive interactions between plate tectonics and plume tectonics throughout the history of the earth and the considerable influence of plumes on plate ***,we can acquire a comprehensive understanding of the driving forces for plate motion and operation mechanism of the earth's dynamic system only through joint analyses and integrated studies on plate tectonics and plume tectonics.

关键词： Driving forces for plate motion,Negative buoyancy of plates Subduction tectonics Plume tectonics

Sensitive MoS_(2)photodetector cell with high air-stability for multifunctional in-sensor computing

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Chip 2022年第3期1卷 61-68页

作者： Dong-Hui Zhao Zheng-Hao Gu Tian-Yu Wang Xiao-Jiao Guo Xi-Xi Jiang Min Zhang Hao Zhu Lin Chen Qing-Qing Sun David Wei Zhang State Key Laboratory of ASIC and System School of MicroelectronicsFudan UniversityShanghai 200433China Zhangjiang Fudan International innova-tion Center Shanghai 201203China College of Data science Jiaxing Univer-sityJiaxing City 314001China

With the development of artificial intelligence and the Internet of Things,the number of sensory nodes is growing rapidly,leading to the exchange of large quantities of redundant data between sensors and computing *** computing schemes,which integrate sensing and processing,have provided a promising route to addressing the sensing/processing bottleneck by reducing power consumption,time delay and hardware *** this study,an in-sensor computing architecture involving a photoelectronic cell based on a wafer-scale two-dimensional MoS_(2)thin film was *** MoS_(2)photodetector cell used a top-gate device structure with in-dium tin oxide(ITO)as the transparent gate electrode,which exhibited high air-stability and a high photoresponsivity(R)up to 555.8 A W^(-1) at an illumination power density(P_(in))of 16.0μW cm^(-2)(λ=500 nm).Additionally,a MoS_(2)photodetector array with uniform photoresponsive characteristics was ***,logic gates,including inverter,NAND,and NOR,were achieved based on MoS_(2)photodetector *** multifunctional and robust in-sensor computing was ascribed to the uniform wafer-scale MoS_(2)film grown by atomic layer deposition(ALD)and the unique device *** the detection of optical signals and logic operations were achieved through MoS_(2)photodetector cells with area efficiency,the proposed in-sensor computing device paves the way for potential applications in high-performance,integrated sensing and processing systems.

关键词： In-sensor computing Photodetectors MoS_(2) Atomic layer de-position Transparent electrode

Energetics characteristics of the super magnetic storm on November 20,2003 based on 3D global MHD simulation

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science China earth sciences 2014年第12期57卷 3035-3046页

作者： HAN JinPeng WANG Chi LI Hui State Key Laboratory of Space Weather Center for Space Science and Applied ResearchChinese Academy of Sciences College of earth science University of the Chinese Academy of Sciences

The three-dimensional global magnetohydrodynamic model(PPM-LR MHD)is employed to investigate the energy budget in the solar wind-magnetosphere system during the super magnetic storm on November 20,2003,one of the biggest storms during the last decade with Dst^-500 n *** this event,about 23%solar wind kinetic energy is transferred into the *** total energy input is estimated to be about 9.50×1017 J,about 14 times of a moderate *** energy dissipation via the inner magnetosphere is less than the energy input with the coupling efficiency of^63.3%.The energy dissipated via ring current injection is less than that via high-latitude ionosphere at the initial stage of the super ***,both the simulation results and the empirical results indicate that the ratio of ring current injection to the total energy output increases with the enhancement of the magnetospheric activity *** are consistent with the statistical results we have got *** empirical equations underestimate the solar wind kinetic energy,the energy input,and the energy dissipation via high-latitude ionosphere compared with the simulation results;however,the coupling efficiency of the high-latitude ionosphere(23.4%)is close to the simulation result(23.1%)during the entire storm time period.

关键词： MHD simulation energy budget super storm energy coupling function

Photoluminescence and thermoluminescence properties of dysprosium doped zinc metaborate phosphors

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Journal of Rare earths 2008年第2期26卷 203-206页

作者：李娟张纯祥唐强郝景权张彦立苏锵王淑彬 Chemistry and Biology College Beihua University Department of Physics Sun Yat-Sen University Key Laboratory of Rare earth Chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Ionizing Radia- tion Division National Institute of Metrology

Polycrystalline powder samples of dysprosium doped Zn（BO2）2 phosphors were prepared by solid state reaction in air at high temperature and characterized by X-ray powder diffraction. The IR, Photoluminescence （PL）, diffuse reflectance and three-dimensional （3D） thermoluminescence （TL） emission spectrum after 60^Co gamma ray irradiation were investigated. The characteristic 3D TL emission bands at about 425, 481 and 573 um with a main emission band of around 573 um were attributed to the host emission, 4^F9/2→6H15/2 and F9/2→6^H13/2 f-f transitions of Dy^3＋ ions. No emission from Dy^2＋ ions was observed in the measurement wavelength range. The TL-dose response of the Zn（BO2）2：Dy polycrystalline powder sample to gamma ray radiation in the range from 1 to 100 Gy at clinical dose levels was almost linear. The experimental results showed that Zn（BO2）2：Dy had potential use as the materials of gamma-ray thermoluminescence dosimeter （TLD） for clinical dosimetry.

关键词： thermoluminescence dysprosium dosimetry zinc metaborate Gamma-ray rare earths

Structural Networks Constraints on Alteration and Mineralization Processes in the Jiaojia Gold Deposit, Jiaodong Peninsula, China

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Journal of earth science 2020年第3期31卷 500-513页

作者： Huanlong Hu Shuangliang Liu Hong-Rui Fan Kuifeng Yang Yabin Zuo Yachun Cai Key Laboratory of Mineral Resources Institute of Geology and Geophysics.Chinese Academy of SciencesBeijing 100029China College of earth and Planetary sciences University of Chinese Academy of SciencesBeijing 100049China innovation academy for earth science Chinese Academy of SciencesBeijing 100029China

Structural network studies could give appropriate opportunities to understanding structural/hydrothermal events,transportation of ore-forming fluids and water/rock interaction *** structural deformation/hydrothermal events have been identified in the Jiaojia fault zone according to microtexture and deformation of quartz and *** experienced ductile deformation period with bended polysynthetic twin stripes(>450℃)in the early stage,followed by K-feldspar alteration period with ductile-brittle deformation and subgrain rotation recrystallization of quartz(380-450℃).Then,sericitization period occurred extensive ductile-brittle deformation(350-420℃)and extensive subgrain rotation recrystallization with a little bulging recrystallization in *** the last,gold precipitation-related pyrite-sericite-quartz alteration was dominated by brittle deformation(300-380℃)and total bulging recrystallization of *** the K-feldspar alteration zone and sericitization zone to pyrite-sericitequartz alteration zone,fractal dimension values of dynamically recrystallized quartz grains increase from 1.07 and 1.24 to 1.32,the calculated paleo strain rate values of dynamically recrystallized quartz range from 10^-10^.7(380℃)-10^-9.6(450℃)and 10^-9.3(350℃)-10^-8.2(420℃)to 10^-9.5(300℃)-10^-8.0(380℃),and the paleo differential stress values increase from 36.9 and 39.3,to 121.3 *** increase of fractal dimension values and decrease of grain size from pyrite-sericite-quartz alteration zone and sericitization zone to K-feldspar alteration zone decreased average water/rock ratio values,which could lead to different acidity and redox conditions of ore-forming fluids and mineralization *** kinds of orecontrolling fractures have been distinguished which include the gentle dip types(18°-50°)with NW(315°-355°)and SW(180°-235°)dip hosting No.Ⅰorebodies and the steep dip types(74°-90°)with NE(45°-85°)and SE(95°-165°)dip hosting No.Ⅲ*** faults/fr

关键词： ore-controlling structural networks brittle-ductile deformation dynamic recrystallization of quartz fractal of quartz connection in the space Jiaojia Gold Deposit

Comparing spatiotemporal patterns in Eurasian FPAR derived from two NDVI-based methods

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International Journal of Digital earth 2012年第4期5卷 283-298页

作者： Dailiang Peng Bing Zhang Liangyun Liu Center for earth Observation and Digital earth Chinese Academy of SciencesBeijingChina

A long-term,consistent Fraction of Absorbed Photosynthetically Active Radiation(FPAR)product is necessary to study the spatial and temporal patterns of vegetation dynamics associated with climatic changes and human *** this study,Eurasia was selected as the study *** relationship between FPAR and simple infrared/red ratio relationship(SR FPAR),and that between Moderate Resolution Imaging Spectroradiometer(MODIS)FPAR and a Normalised Difference Vegetation Index(NDVI)look-up table(LUT FPAR)were employed to estimate FPAR from 1982 to 2006 by different land cover types,focusing on the comparisons of spatiotemporal FPAR patterns between the two FPAR *** results showed high agreement between MODIS standard FPAR and estimated FPAR in seasonal dynamics with peak values in *** LUT FPAR was close to MODIS standard FPAR and larger than SR *** SR and LUT FPAR showed the same spatial distribution and inter-annual variation patterns and were primarily determined by land cover *** overall increasing trend in FPAR was observed from 1982 to 2006,with reductions from 1991 to 1994 and 2000 to *** inter-annual dynamics in evergreen broadleaf forests showed a decreasing trend over 25 years,while non-forest vegetation FPAR values had slow,stable growth in inter-annual variation.

关键词： spatiotemporal patterns FPAR NDVI-based method Eurasia

Bounding of near-fault ground motion based on radiated seismic energy with a consideration of fault frictional mechanisms

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earthquake science 2010年第4期23卷 357-368页

作者： Baoping Shi Boyan Liu Lingyuan Meng earth science Colleg the Graduate School Chinese Academy of Seiences Beijing 100049 China

The energy radiated as seismic waves strongly depends on the fault rupture process associated with rupture speed and dynamic frictional mechanisms involved in the fault slip motion. Following McGarr and Fletcher approach, we derived a physics-based relationship of the weighted average fault slip velocity vs apparent stress, rupture speed and static stress drop based on a dynamic circular fault model. The resultant function can be approximately used to bound near-fault ground motion and seismic energy associated with near-fault coseismic deformation. Fault frictional overshoot and under- shoot mechanisms governed by a simple slip-weakening constitutive relation are included in our consideration by using dy- namic rupture models named as M- and D-models and proposed by Madariaga （1976） and Boatwright. We applied the above function to the 2008 great Wenchuan earthquake and the 1999 Jiji （Chi-Chi） earthquake to infer the near-fault ground motion called slip weighted average particle velocity and obtained that such model-dependent prediction of weighted average ground velocities is consistent to the results derived from the near-fault strong motion observations. Moreover, we compared our re- sults with the results by McGarr and Fletcher approach, and we found that the values of the weighted average particle veloci- ties we obtained for these two earthquakes are generally smaller and closer to the values by direct integration of strong mo- tion recordings of the near-fault particle velocity waveform data. In other words, if this result comes to be true, it would be a straightforward way used to constrain the near-fault ground motion or to estimate source parameters such as rupture speed, static and dynamic stress drops.

关键词： stress drop radiated energy apparent stress circular-fault-model rupture speed

The ocean's role in climate variability

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Acta Oceanologica Sinica 2008年第z1期27卷 1-8页

作者： CHEN Dake State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography State Oceanic Administra-tion Hangzhou 310012 China Lamont - Doherty earth Observatory of Columbia University Palisades New York USA

Because of its vast volume and heat capacity, the ocean contains most of the memory of the earth's ocean-atmosphere coupled system. It has been suggested that the ocean may delay global warming by absorbing large amounts of heat, that it may cause abrupt climate change due to its disrupted thermohaline circulation, and that it may set the time-scales for various climate oscillations. Although the slow pace and persistence of oceanic variations give hope to long-range prediction, there still exist large uncertainties in climate predictability. Presently available observations and models are generally inadequate for studying and predicting long-term climate changes. However, some short-term fluctuations such as ENSO have been well studied and shown to be highly predictable even with simplified models.

关键词： ocean climate variability predictability.