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Source apportionment and suitability evaluation of seasonal VOCs contaminants in the soil around a typical refining-chemical integration park in China

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Journal of Environmental Sciences 2024年第3期137卷 651-663页

作者： Xu Zhao Jing Meng Qianqian Li Guijin Su Qifan Zhang Bin Shi Lingwen Dai Yong Yu Key Laboratory of Environmental Nanotechnology and Health Effects State Key Laboratory of Environmental Chemistry and EcotoxicologyResearch Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China state Environmental Protection Key Laboratory of Quality Control in Environmental monitoring China National Environmental Monitoring CenterBeijing 100012China

Accurate source apportionment of volatile organic compounds(VOCs)in soil nearby petrochemical industries prevailing globally,is critical for preventing ***,in the process,seasonal effect on contamination pathways and accumulation of soil VOCs is often ***,Yanshan Refining-Chemical Integration Park,including a carpet,refining,synthetic rubber,and two synthetic resin zones,was selected for *** variations resulted in a gradual decrease of 31 VOCs in soil from winter to summer.A method of dry deposition resistance model coupling partitioning coefficient model was created,revealing that dry deposition by gas phase was the primary pathway for VOCs to enter soil in winter and spring,with 100 times higher fux than by particle *** profiles for five zones were built by gas sampling with distinct substance indicators screened,which were used for positive matrix factorization factors *** of the five zones were 14.9%,20.8%,13.6%,22.1%,and 28.6%in winter and 33.4%,12.5%,10.7%,24.9%,and 18.5%in spring,*** variation in the soil sorption capacity of VOCs causes inter-seasonal differences in *** better correlation between dry deposition capacity and soil storage of VOCs made root mean square and mean absolute errors decrease averagely by 8.8%and 5.5%in winter compared to *** study provides new perspectives and methods for the source apportionment of soil VOCs contamination in industrial sites.

关键词： Dry deposition resistance model Positive matrix factorization model Partitioning coefficient model Contamination pathway Source profile

Effect of hot isostatic pressure on the microstructure and tensile properties of γ'-strengthened superalloy fabricated through induction-assisted directed energy deposition

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1089-1097页

作者： Jianjun Xu Hanlin Ding Xin Lin Feng Liu Analytical&testing center Northwestern Polytechnical UniversityXi’an 710072China state Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

The microstructure characteristics and strengthening mechanism of Inconel738LC(IN-738LC) alloy prepared by using induction-assisted directed energy deposition(IDED) were elucidated through the investigation of samples subjected to IDED under 1050℃ preheating with and without hot isostatic pressing(HIP,1190℃,105 MPa,and 3 h).Results show that the as-deposited sample mainly consisted of epitaxial columnar crystals and inhomogeneously distributed γ’ phases in interdendritic and dendritic core *** HIP,grain morphology changed negligibly,whereas the size of the γ’ phase became increasingly *** further heat treatment(HT,1070℃,2 h + 845℃,24 h),the γ’ phase in the as-deposited and HIPed samples presented a bimodal size distribution,whereas that in the as-deposited sample showed a size that remained *** comparison of tensile properties revealed that the tensile strength and uniform elongation of the HIP + HTed sample increased by 5% and 46%,respectively,due to the synergistic deformation of bimodal γ’phases,especially large cubic γ’ ***,the relationship between phase transformations and plastic deformations in the IDEDed sample was discussed on the basis of generalized stability theory in terms of the trade-off between thermodynamics and kinetics.

关键词： directed energy deposition Ni-based superalloys high-temperature preheating hot isostatic pressing microstructure tensile properties

Thermo-kinetic characteristics on stabilizing hetero-phase interface of metal matrix composites by crystal plasticity finite element method

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Journal of Materials Science & Technology 2024年第2期169卷 53-67页

作者： Y.B.Zhang S.J.Song F.Liu state Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Analytical&testing center Northwestern Polytechnical UniversityXi’an 710072China

Using dislocation-based constitutive modeling in three-dimension crystal plasticity finite element(3D CPFE)simulations,co-deformation and instability of hetero-phase interface in different material systems were herein studied for polycrystalline metal matrix composites(MMCs).Local stress and strain fields in two types of 3layer MMCs such as fcc/fcc Cu-Ag and fcc/bcc Cu-Nb have been predicted under simple compressive ***,more severe strain-induced interface instability can be observed in the fcc/bcc systems than in the fcc/fcc systems upon refining to metallic nanolayered composites(MNCs).By detailed analysis of stress and strain localization,it has been demonstrated that the interface instability is always accompanied by high-stress concentration,i.e.,thermodynamic characteristics,or high strain prevention i.e.,kinetic characteristics,at the hetero-phase *** then follows that the thermodynamic driving forceG and the kinetic energy barrier Q during dislocation and shear banding can be adopted to classify the deformation modes,following the so-called thermo-kinetic *** by inserting a high density of high-energy interfaces into the Cu-Nb composites,such thermo-kinetic integration at the hetero-phase interface allows a successful establishment of MMCs with the high△G-high Q deformation mode,which ensures high hardening and uniform strain distri-bution,thus efficiently suppressing the shear band,stabilizing the hetero-phase interface,and obtaining an exceptional combination in strength and *** hetero-phase interface chosen by a couple of thermodynamics and kinetics can be defined as breaking the thermo-kinetic correlation and has been proposed for artificially designing MNCs.

关键词： Thermodynamics and kinetics Physics-based constitutive modeling Hetero-phase interface Crystal plasticity finite element

Characteristics and source apportionment of ambient volatile organic compounds and ozone generation sensitivity in urban Jiaozuo,China

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Journal of Environmental Sciences 2024年第4期138卷 607-625页

作者： Pengzhao Li Chun Chen Dan Liu Jie Lian Wei Li Chuanyi Fan Liangyu Yan Yue Gao Miao Wang Hang Liu Xiaole Pan Jing Mao state Centre for International Cooperation on Designer Low-Carbon and Environmental Materials School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China Henan Key Laboratory of Environmental monitoring Technology Henan Ecological Environment Monitoring and Safety CenterZhengzhou 450046China Jiaozuo Ecological Environment monitoring center of Henan Province Jiaozuo 454003China state Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

In recent years,many cities have taken measures to reduce volatile organic compounds(VOCs),an important precursor of ozone(O_(3)),to alleviate O_(3) pollution in China.116 VOC species were measured by online and offline methods in the urban area of Jiaozuo from May to October in 2021 to analyze the compositional *** sources were analyzed by a positive matrix factorization(PMF)model,and the sensitivity of ozone generation was determined by ozone isopleth plotting research(OZIPR)*** results showed that the average volume concentration of total VOCs was 30.54 ppbv and showed a bimodal feature due to the rush-hour traffic in the morning and at *** most dominant VOC groups were oxygenated VOCs(OVOCs,29.3%)and alkanes(26.7%),and the most abundant VOC species were acetone and ***,based on the maximum incremental reactivity(MIR)method,the major VOC groups in terms of ozone formation potential(OFP)contribution were OVOCs(68.09μg/m^(3),31.5%),aromatics(62.90μg/m^(3),29.1%)and alkene/alkynes(54.90μg/m^(3),25.4%).This indicates that the control of OVOCs,aromatics and alkene/alkynes should take *** sources of VOCs were quantified by PMF,including fixed sources of fossil fuel combustion(27.8%),industrial processes(25.9%),vehicle exhaust(19.7%),natural and secondary formation(13.9%)and solvent usage(12.7%).The empirical kinetic modeling approach(EKMA)curve obtained by OZIPR on O_(3) exceedance days indicated that the O_(3) sensitivity varied in different *** results provide theoretical support for O_(3) pollution prevention and control in Jiaozuo.

关键词： Volatile organic compounds(VOCs) Online and offline measurement Ozone formation potential(OFP) Positive matrix factorization(PMF) Ozone isopleth plotting research(OZIPR) Jiaozuo

Dynamic manipulation of multimodal emission in Er^(3+)-activated non-core-shell structure for optical thermometry and information security

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Rare Metals 2024年第4期43卷 1702-1712页

作者： Xuan Liu Zi-Xia Lin Yin-Biao Shi Xiao-Yan Wang Ming-Ye Ding Xiao-Fei Yang College of Science Nanjing Forestry UniversityNanjing210037China testing center Yangzhou UniversityYangzhou225009China

Regulating luminescent dynamics of lanthanide-based luminescent materials via external stimuli is of great significance in the fields of optical thermometry and high-level ***,it is still a huge challenge to realize multimodal emissions with tunable color outputs from a single activator in simple structures via smart dynamic control of photon transition ***,we present a mechanistic strategy to achieve multimodal luminescence of Er^(3+)activators with color-switchable outputs in a non-core-shell *** the control of excitation dynamics(λ_(ex)=980,808,1532,377 nm),the population among the intermediate en ergy levels of Er^(3+)and the interaction between Er^(3+)and Yb^(3+)could be precisely modulated through energy transfer and migration processes,leading to the generation of colortunable multimodal luminescence upon diverse excitation modes(non-steady-state,single-/dual-wavelength steady,thermal activation).Inspired by its special luminescent performance,the as-obtained material exhibits great potential in noncontact thermometry,multimodal anticounterfeiting,and high-capacity information encryption by performing a series of proof-of-concept *** findings might provide a conceptual model to modulate the luminescent dynamics in a simple-structured system for the generation of color-adjustable multimodal emissions,which is convenient for the development of advanced luminescent materials toward versatile cuttingedge applications.

关键词： Lanthanide ions Multimodal emission Upconversion Downshifting Anti-counterfeiting Luminescent thermometry

Phenology of different types of vegetation and their response to climate change in the Qilian Mountains,China

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Journal of Mountain Science 2024年第2期21卷 511-525页

作者： ZHAO Kaixin LI Xuemei ZHANG Zhengrong LIU Xinyu Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China National-Local Joint Engineering Research center of Technologies and Applications for National Geographic state monitoring Lanzhou 730070China Gansu Provincial Engineering Laboratory for National Geographic state monitoring Lanzhou 730070China

The Qilian Mountains(QM)possess a delicate vegetation ecosystem,amplifying the evident response of vegetation phenology to climate *** relationship between changes in vegetation growth and climate remains *** this end,we used MODIS NDVI data to extract the phenological parameters of the vegetation including meadow(MDW),grassland(GSD),and alpine vegetation(ALV))in the QM from 2002 to ***,we employed path analysis to reveal the direct and indirect impacts of seasonal climate change on vegetation ***,we decomposed the vegetation phenology in a time series using the trigonometric seasonality,Box-Cox transformation,ARMA errors,and Trend Seasonal components model(TBATS).The findings showed a distinct pattern in the vegetation phenology of the QM,characterized by a progressive shift towards an earlier start of the growing season(SOS),a delayed end of the growing season(EOS),and an extended length of the growing season(LOS).The growth cycle of MDW,GSD,and ALV in the QM species is clearly *** SOS for MDW and GSD occurred earlier,mainly between late April and August,while the SOS for ALVs occurred between mid-May and mid-August,a one-month delay compared to the other *** EOS in MDW and GSD were concentrated between late August and April and early September and early January,*** phenology exhibits distinct responses to seasonal temperature and precipitation *** advancement and delay of SOS were mainly influenced by the direct effect of spring temperatures and precipitation,which affected 19.59%and 22.17%of the study area,*** advancement and delay of EOS were mainly influenced by the direct effect of fall temperatures and precipitation,which affected 30.18%and 21.17%of the area,*** the contrary,the direct effects of temperature and precipitation in summer and winter on vegetation phenology seem less noticeable and were mainly influenced by indirect *** indirec

关键词： Vegetation phenology Time series decomposition Path Analysis Climate change

Channel estimation in integrated radar and communication systems with power amplifier distortion

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Journal of Systems Engineering and Electronics 2024年第5期35卷 1098-1108页

作者： LIU Yan YI Jianxin WAN Xianrong RAO Yunhua HAO Caiyong School of Electronic Information Wuhan UniversityWuhan 430072China Shenzhen Research Institute of Wuhan University Shenzhen 518057China state radio monitoring center of China Shenzhen 518120China

To reduce the negative impact of the power amplifier(PA)nonlinear distortion caused by the orthogonal frequency division multiplexing(OFDM)waveform with high peak-to-average power ratio(PAPR)in integrated radar and communication(RadCom)systems is studied,the channel estimation in passive sensing *** channel estimation methods are proposed based on different pilot patterns,considering nonlinear distortion and channel *** proposed methods achieve sparse channel results by manipulating the least squares(LS)frequency-domain channel estimation results to preserve the most significant *** decision-aided method is used to optimize the sparse channel results to reduce the effect of nonlinear *** results show that the channel estimation performance of the proposed methods is better than that of the conventional methods under different pilot *** addition,the bit error rate performance in communication and passive radar detection performance show that the proposed methods have good comprehensive performance.

关键词： channel estimation integrated radar and communication(RadCom) passive sensing nonlinear distortion power amplifier(PA) pilot pattern

Study on the fast elimination of smoke particle based on electro-acoustic coupling agglomeration technology

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Particuology 2024年第5期88卷 1-10页

作者： Jie Feng Mingfeng Lu Kaige Wang Kun Luo Mingzhou Yu Guangxue Zhang Jiangrong Xu Shuping Pan Hailin Gu The Institute for Energy Engineering China Jiliang UniversityHangzhou310018China state Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou310027China Qingshanhu Energy Research center Zhejiang UniversityHangzhou310017China Zhejiang Ecological Environment monitoring center Hangzhou310012China

Fire smoke,which consists large amounts of fine particles,is considered as the fatal factor in *** this study,a fast smoke particle elimination method based on electro-acoustic coupling agglomeration technology is ***,the experimental results show that the electro-acoustic coupling agglomeration has higher smoke elimination efficiency compared to *** smoke transmission is much less than 80%after 30s of single acoustic or electric field action,while the coupled field reaches 90%.Then,the effects of acoustic frequency,sound pressure level and voltage on the smoke elimination characteristics are *** is found that the optimal acoustic frequency is *** as the sound pressure level and voltage increase,the elimination efficiency first increases and then tends to stabilize,the critical values of the sound pressure level and voltage are 135 dB and *** indicates that there is an optimal combination of the three ***,through the theoretical analysis of particle movement and the micro-morphology of agglomerates,the particle agglomeration mechanism under the electro-acoustic coupling is *** study provides a new idea for the fast elimination of fire smoke particle.

关键词： Smoke particle Agglomeration Electro-acoustic coupling Smoke elimination

SO_(2)and SOF_(2)simultaneous detection by single mid-infrared laser based on tunable diode laser absorption spectroscopy

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High Voltage 2024年第4期9卷 786-793页

作者： Yin Zhang Yan Li Jin Yan Chao Bian Xuan Chen Xiaoxing Zhang Hubei Engineering Research center for Safety monitoring of New Energy and Power Grid Equipment Hubei University of TechnologyWuhanChina state Grid Jiangsu Electric Power Co. Ltd.Ultra High Voltage BranchNanjingChina

In the detection of multi-component gas based on tunable diode laser absorption spectroscopy(TDLAS),the problem of overlapping interference between the absorption lines of each gas is often *** example,when detecting a gas mixture of sulphur dioxide(SO_(2))and thionyl fluoride(SOF_(2)),the characteristic decomposition components of SF6,there is overlapping interference in the absorption lines of the two gases,which makes it difficult to detect the concentration of gases *** view of this problem,a novel method based on support vector regression model used for TDLAS is proposed to detect two gases *** detection results show that the correlation coefficients between the concentration of SO_(2)and SOF_(2)and the average value of the second harmonic peak reached 0.992 and *** addition,through model testing,different concentrations of SO_(2)and SOF_(2)gas mixture are simultaneously detected,and the resulting maximum errors for measuring SO_(2)and SOF_(2)concentrations are less than 7.13×10^(-5)and 0.26×10^(-2).The maximum errors of the measurement results in the verification test are not more than 6.4×10^(-3)and 4.6×10^(-2).Therefore,with assistance of the novel method,the detection of multiple gases by using a single laser is achieved.

关键词： tunable diode absorption