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Time-sensitive prediction of NO_(2) concentration in China using an ensemble machine learning model from multi-source data

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Journal of Environmental Sciences 2024年第3期137卷 30-40页

作者： Chenliang Tao Man Jia Guoqiang Wang Yuqiang zhang Qingzhu Zhang Xianfeng Wang Qiao Wang Wenxing Wang Big Data Research Center for Ecology and Environment Environment Research InstituteShandong UniversityQingdao 266237China Shandong Provincial Eco-environment Monitoring Center Jinan 250101China

Nitrogen dioxide(NO_(2))poses a critical potential risk to environmental quality and public health.A reliable machine learning(ML)forecasting framework will be useful to provide valuable information to support government decision-making.Based on the data from1609 air quality monitors across China from 2014-2020,this study designed an ensemble ML model by integrating multiple types of spatial-temporal variables and three sub-models for time-sensitive prediction over a wide range.The ensemble ML model incorporates a residual connection to the gated recurrent unit(GRU)network and adopts the advantage of Transformer,extreme gradient boosting(XGBoost)and GRU with residual connection network,resulting in a 4.1%±1.0%lower root mean square error over XGBoost for the test results.The ensemble model shows great prediction performance,with coefficient of determination of 0.91,0.86,and 0.77 for 1-hr,3-hr,and 24-hr averages for the test results,respectively.In particular,this model has achieved excellent performance with low spatial uncertainty in Central,East,and North China,the major site-dense zones.Through the interpretability analysis based on the Shapley value for different temporal resolutions,we found that the contribution of atmospheric chemical processes is more important for hourly predictions compared with the daily scale predictions,while the impact of meteorological conditions would be ever-prominent for the latter.Compared with existing models for different spatiotemporal scales,the present model can be implemented at any air quality monitoring station across China to facilitate achieving rapid and dependable forecast of NO_(2),which will help developing effective control policies.

关键词： Air quality prediction Deep learning Ensemble method Nitrogen dioxide Spatiotemporal covariates

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Effects of the VGS sweep range on the short channel effect in negative capacitance FinFETs

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Science China(Information Sciences) 2024年第6期 463-464页

作者： Fan zhang Zhaohao zhang Jiaxin YAO Qingzhu Zhang Gaobo XU Zhenhua WU Huan LIU Genquan HAN Yan LIU Huaxiang YIN Integrated Circuit Advanced Process R&D Center State Key Lab of Fabrication Technologies for Integrated CircuitsInstitute of Microelectronics of Chinese Academy of Sciences School of Microelectronics Xidian University School of Integrated Circuits University of Chinese Academy of Sciences

As the CMOS technology scaling is reaching fundamental limits,there is a substantial demand for energy-efficient devices with lower operating voltage.Negative capacitance field-effect transistors （NCFETs） exhibit the capability to amplify the gate voltage and become promising candidates for future advanced process nodes.Ferroelectric （FE） HfO2-based materials,

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Designing metal sulfide-based cathodes and separators for suppressing polysulfide shuttling in lithium-sulfur batteries

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Nano Research 2024年第4期17卷 2574-2591页

作者： Guoyin Zhu qingzhu Wu Xianghua zhang Yuwen Bao Xuan zhang Zhuoyao Shi Yizhou zhang Lianbo Ma Institute of Advanced Materials and Flexible Electronics(IAMFE) School of Chemistry and Materials ScienceNanjing University of Information Science&TechnologyNanjing 210044China School of Materials Science and Engineering Anhui University of TechnologyMaanshan 243002China School of Mechanical Engineering Jiangsu University of TechnologyChangzhou 213001China

Lithium-sulfur(Li-S)batteries,known for their high energy density,are attracting extensive research interest as a promising next-generation energy storage technology.However,their widespread use has been hampered by certain issues,including the dissolution and migration of polysulfides,along with sluggish redox kinetics.Metal sulfides present a promising solution to these obstacles regarding their high electrical conductivity,strong chemical adsorption with polysulfides,and remarkable electrocatalytic capabilities for polysulfide conversion.In this review,the recent progress on the utilization of metal sulfide for suppressing polysulfide shuttling in Li-S batteries is systematically summarized,with a special focus on sulfur hosts and functional separators.The critical roles of metal sulfides in realizing high-performing Li-S batteries have been comprehensively discussed by correlating the materials’structure and electrochemical performances.Moreover,the remaining issues/challenges and future perspectives are highlighted.By offering a detailed understanding of the crucial roles of metal sulfides,this review dedicates to contributing valuable knowledge for the pursuit of high-efficiency Li-S batteries based on metal sulfides.

关键词： lithium-sulfur batteries metal sulfides polysulfide shuttling sulfur hosts separator coating layers

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A review on the transformation of birnessite in the environment:Implication for the stabilization of heavy metals

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Journal of Environmental Sciences 2024年第5期139卷 496-515页

作者： Miao Shi qingzhu Li Qingwei Wang Xuelei Yan Bensheng Li Linhai Feng Chao Wu Rongrong Qiu Hongkai zhang Zhihui Yang Weichun Yang Qi Liao Liyuan Chai School of Metallurgy and Environment Central South UniversityChangsha 410083China National Engineering Research Centre for Control and Treatment ofHeavy Metal Pollution Central South UniversityChangsha 410083China Water Pollution Control Technology Key Lab of Hunan Province Changsha 410083China

Birnessite is ubiquitous in the natural environment where heavy metals are retained and easily transformed.The surface properties and structure of birnessite change with the changes in external environmental conditions,which also affects the fate of heavy metals.Clarifying the effect and mechanism of the birnessite phase transition process on heavy metals is the key to taking effective measures to prevent and control heavy metal pollution.Therefore,the four transformation pathways of birnessite are summarized first in this review.Second,the relationship between transformation pathways and environmental conditions is proposed.These relevant environmental conditions include abiotic(e.g.,co-existing ions,pH,oxygen pressure,temperature,electric field,light,aging,pressure)and biotic factors(e.g.,microorganisms,biomolecules).The phase transformation is achieved by the key intermediate of Mn(Ⅲ)through interlayer-condensation,folding,neutralizationdisproportionation,and dissolution-recrystallization mechanisms.The AOS(average oxidation state)of Mn and interlayer spacing are closely correlated with the phase transformation of birnessite.Last but not least,the mechanisms of heavy metals immobilization in the transformation process of birnessite are summed up.They involve isomorphous substitution,redox,complexation,hydration/dehydration,etc.The transformation of birnessite and its implication on heavy metals will be helpful for understanding and predicting the behavior of heavy metals and the crucial phase of manganese oxides/hydroxides in natural and engineered environments.

关键词： Birnessite Transformation Heavy metals Pathways Mechanism

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Nanosize-effect on the distribution of heavy metals in copper smelting dust:Based on sophisticated dust sorting approach

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Nano Research 2024年第1期17卷 312-320页

作者： Ken Li Zuwu Liao Hengdi Ye qingzhu Li Fenghua Shen Qian Li Hui Liu Qingwei Wang Xu Yan zhang Lin Liyuan Chai School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution Changsha 410083China National Engineering Research Center of Sintering and Pelletizing Equipment System Zhongye Changtian International Engineering Co.LtdChangsha 410205China

Dust particles emitted from smelters can be hazardous to ecosystems and humans,as they are often enriched in metallic compounds.Here,we combined multi-method mineralogical analysis with a sophisticated size sorting approach for copper smelting dust to study the nanosize-effect on heavy metal distribution,which has hitherto been underestimated.Three types of dust were collected from a copper flash smelter and then size-sorted using a Dekati low-pressure impactor.Results showed that all three samples could easily sort out nanoscale dust particles(<1μm,grades 10–2)and even those smaller than 100 nm(grades 5–2).Especially for electrostatic precipitators dust,the mass fraction of nanoscale dust(<1μm)could reach 10.71%.The presence of heavy metals(Pb,Zn,Cu,and As)and their mineral species in dust was examined at various particle sizes.It was discovered that different heavy metals are enriched on nanoparticles in specific sizes.In micron-sized particles,heavy metals are generally found in discrete phases(e.g.,CuSO_(4),PbSO_(4),and As_(2)O_(3)).In nanoscale particles,the dominant phase is Fe_(3)O_(4),while heavy metals are mostly found in lattice substitution(e.g.,CuFe_(2)O_(4)and ZnFe_(2)O_(4)).Two distinct nano-dust morphologies were found:One with irregular mesh or chain structures consisting of particles of a few nanometers,and the other with polygonal crystals in larger sizes of hundreds of nanometers.The enrichment of heavy metals in the latter morphology is more pronounced,possibly because lattice substitution of heavy metals is more likely to occur when polycrystalline particles are formed.

关键词： copper flue dust size-sorted heavy metal distribution morphology nano-sized effects

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Recent progress of hafnium oxide-based ferroelectric devices for advanced circuit applications

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Science China(Information Sciences) 2023年第10期66卷 84-104页

作者： Zhaohao zhang Guoliang TIAN Jiali HUO Fang zhang Qingzhu Zhang Gaobo XU Zhenhua WU Yan CHENG Yan LIU Huaxiang YIN Integrated Circuit Advanced R&D Center Institute of Microelectronics of Chinese Academy of Sciences School of Integrated Circuits University of Chinese Academy of Sciences School of Microelectronics Xidian University Department of Electronics East China Normal University

Hafnium oxide-based ferroelectric field-effect-transistors(FeFET), which combine super-steep logical switching and low power non-volatile memory functions, have significant potential for post-Moore integrated circuit innovations with higher energy efficiency and larger integration scale. In this review, recent research into hafnium oxide-based ferroelectric(FE) films and different functional devices is presented,from fundamentals to applications. Different technological challenges and state-of-the-art research and development efforts related to the physical understanding and performance optimization of FE films, advanced hafnium oxide-based device integration, and device applications in logic-in-memory and artificial synapses and neurons for neuromorphic computing are addressed.

关键词： ferroelectric FeFET hafnium oxide HZO logic-in-memory neuromorphic computing

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Interactions of sulfuric acid with common atmospheric bases and organic acids: Thermodynamics and implications to new particle formation

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Journal of Environmental Sciences 2020年第9期32卷 130-140页

作者： Yunfeng Li Haijie zhang Qingzhu Zhang Yisheng Xu Alexey B.Nadykto Environment Research Institute Shandong UniversityQingdao 266237China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental ScienceBeijing 100012China Department of Applied Mathematics Moscow State University of Technology“Stankin”Moscow 127994Russia

Interactions of the three common atmospheric bases,dimethylamine((CH3)2 NH),methylamine(CH3 NH2),ammonia(NH3),all considered to be efficient stabilizers of binary clusters in the Earth’s atmosphere,with H2 SO4,the key atmospheric precursor,and 14 common atmospheric organic acids(COAs)(formic,acetic,oxalic,malonic,succinic,glutaric acid,adipic,benzoic,phenylacetic,pyruvic,maleic acid,malic,tartaric and pinonic acids)have been studied using the density functional theory(DFT)and composite high-accuracy G3 MP2 method.The thermodynamic stability of mixed(COA)(H2 SO4),(COA)(B1),(COA)(B2)and(COA)(B3)dimers and(COA)(H2 SO4)(B1),(COA)(H2 SO4)(B2)and(COA)(H2 SO4)(B3)trimers,where B1,B2 and B3 refer to(CH3)2 NH,CH3 NH2 and NH3,respectively,have been investigated and their impacts on the thermodynamic stability of clusters containing H2 SO4 have been studied.Our investigation shows that interactions of H2 SO4 with GOA,(CH3)2 NH,CH3 NH2 and NH3 lead to the formation of more stable mixed dimers and trimers than(H2 SO4)2 and(H2 SO4)2(base),respectively,and emphasize the importance of common organic species for early stages of atmospheric nucleation.We also show that although amines are generally confirmed to be more active than NH3 as stabilizers of binary clusters,in some cases mixed trimers containing NH3 are more stable thermodynamically than those containing CH3 NH2.This study indicates an important role of COA,which coexist and interact with that H2 SO4 and common atmospheric bases in the Earth atmosphere,in formation of stable prenucleation clusters and suggests that the impacts of COA on new particle formation(NPF)should be studied in further details.

关键词： bases particle atmospheric

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Epigenetic modification associated with climate regulates betulin biosynthesis in birch

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Journal of Forestry Research 2023年第1期34卷 21-35页

作者： Jiang Wang Bowei Chen Shahid Ali Tianxu zhang Yu Wang He zhang Lishan Wang Yonglan zhang Linan Xie Tingbo Jiang Jing Yin Heike W.Sederoff Gaurav Zinta Ronald R.Sederoff Yuhua Li Qingzhu Zhang State Key Laboratory of Tree Genetics and Breeding Northeast Forestry UniversityHarbin 150040People’s Republic of China College of Life Sciences Northeast Forestry UniversityHarbin 150040People’s Republic of China Forest Biotechnology Group Department of Forestry and Environmental ResourcesNorth Carolina State UniversityRaleighNC 27695USA Biotechnology Division CSIR-Institute of Himalayan Bioresource TechnologyPalampur 176061India

The Betula genus contains pentacyclic triterpenoid betulin known for its environmental adaptation and medicinal properties.However,the mechanisms underlying betulin biosynthesis responding to climate change remain unclear.In this study,the role of epigenetic modification(DNA methylation) in betulin biosynthesis was examined and how climatic factors influence it.Whole-genome bisulfite sequencing was performed for greenhouse-grown Chinese white birch(Betula platyphylla Sukaczev) treated with DNA methylation inhibitor zebularine(ZEB) and a natural birch population in Northeast China.ZEB treatment significantly affected the CHH methylation level of transposable elements and betulin content in a hormesis dose-dependent manner.The methylation and expression of bHLH9,a key transcriptional factor controlling betulin biosynthesis,were also consistently affected by ZEB treatment as a hormetic dose-response.In the natural population,there was a positive correlation between promoter methylation of bHLH9 and summer precipitation,while winter temperature was negatively correlated.Thus climate-dependent methylation of bHLH9 regulates the expression of downstream genes involved in betulin biosynthesis.This study highlights the role of environmental signals to induce epigenetic changes that result in betulin production,possibly helping to develop resilient plants to combat ongoing climate change and enhance secondary metabolite production.

关键词： Epigenetics DNA methylation Betulin bHLH9 transcription factor Hormesis Climate change Secondary metabolite

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Mechanism and rate constants for complete series reactions of 19 fluorophenols with atomic H

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Journal of Environmental Sciences 2014年第1期26卷 154-159页

作者： Rui Gao Xiaoyan Sun Wanni Yu Qingzhu Zhang Wenxing Wang Environment Research Institute Shandong University

Fluorine-containing halogenated fluorophenol may have effect as intermediate species involved in the formation of polyfluorinated dibenzo-p-dioxin/dibenzofurans （PFDDs/Fs）. The mechanism for the atomic H initiated reactions with complete series of nineteen fluorophenol congeners was studies using the density functional theory. At the MPWB1K,/6-31＋G（d,p） level, the geometries and frequencies of reactants, transition states, and products were obtained, and the accurate energetic values were acquired at the MPWB 1K/6-311 ＋G（3df,2p） level. The rate constants were evaluated by the canonical variational transition-state theory with the small curvature tunneling contribution over a wide temperature range of 600-1000 K. The study shows that the intramolecular hydrogen-bond in the ortho-substituted FPs as well as the inductive effect of the electron-withdrawing fluorine and steric repulsion of multiple substitutions may ultimately be responsible for the relative strength of the O-H bonds in FPs. The results can be used for further studies on PFDD/Fs formation mechanism.

关键词： fluorophenols fluorophenoxy radicals atomic H hydrogen bond reaction mechanism rate constants

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Mechanism and kinetic properties of NO_3-initiated atmospheric degradation of DDT

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Journal of Environmental Sciences 2014年第3期26卷 601-607页

作者： Cai Liu Shanqing Li Rui Gao Juan Dang Wenxing Wang Qingzhu Zhang Environment Research Institute Shandong University

In this article, the NO3 radical-initiated atmospheric oxidation degradation of DDT was theoretically investigated using molecular orbital theory calculations. All the calculations of intermediates, transition states and products were performed at the MPWB1K/6-311＋G（3df,2p）//MPWB1K/6- 31＋G（d,p） level of theory. Several energetically favorable reaction pathways were revealed. The formation mechanisms of secondary pollutants were presented and discussed. The rate constants were deduced over the temperature range of 273-333 K using canonical variational transition-state （CVT） theory with the small curvature tunneling （SCT） method. Our study shows that H abstraction from the alkyl group and NO3 addition to the Ca atom of the benzene ring are the dominant reaction pathways. The rate-temperature formula of the overall rate constants is k（T）（DDT＋NO3） = （7.21 ~ 10-15）exp（-153.81/T） cm3/（mol.sec） over the possible atmospheric temperature range of 273-333 K. The atmospheric lifetime of DDT determined by NO3 radical is about 52.5 days, which indicates that it can be degraded in the gas phase within several months.

关键词： DDT NO3 radicals atmospheric oxidation reaction mechanism rate constants

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