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Contamination assessment,source apportionment and associated health risks of PTEs in agricultural soil under five land-use patterns in Sanya,China

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China Geology 2024年第3期7卷 469-479页

作者： Jian-zhou Yang Yan-gang Fu Qiu-li Gong Sheng-ming Ma Jing-jing Gong Jian-weng Gao Zhen-liang Wang Yong-wen Cai Shi-xin Tang Institute of Geophysical and Geochemical Exploration Chinese Academy of Geological SciencesChina Geological SurveyLangfang 065000China Key Laboratory of Coupling Process and Effect of Natural Resources elements Ministry of Natural ResourcesBeijing 100055China

To understand the levels of potentially toxic elements(PTEs)contamination in soils and their effects on human health from different agricultural land use in Sanya,China.128 soil samples(64 topsoil samples and corresponding subsoil samples)were collected from the five representative land-use *** coupled plasma mass spectrometry(ICP-MS),Atomic fluorescence spectrometry(AFS),and Inductively coupled plasma optical emission spectrometry(ICP-OES)were used to determine the content of PTEs(As,Cd,Hg,Cu,Cr,Ni,Pb,Zn,Co,Mo,Sb,and V).Correlation analysis and factor analysis were used to determine the source of ***-accumulation index(I_(geo)),hazard quotient(HQ),and total carcinogenic risk index(TR)were used to measure the PTEs contamination and its relative health *** showed that the average values of 12 PTEs in topsoil were higher than the Hainan soil geochemical baseline,showing different degrees of PTEs accumulation *** concentration of PTEs in the topsoil was lower than those in the subsoil except for Cd and *** I_(geo)revealed that the major accumulated element in soils was As followed by *** apportionment suggested that parent materials and agricultural practices were the dominant factors for PTEs accumulation in the *** risks of soil samples from five land-use patterns presented a trend of paddy field>dry field>woodland>orchard>garden ***,the HQ values of 12 PTEs were less than the recommended limit of HQ=1,representing that there are no non-carcinogenic risks of PTEs for children and adults in the study *** TR values are within 6.95×10^(-6)-1.38×10^(-5),which corresponds to the low *** the PTEs in the agricultural soil of the study area show little influence on the health status of the local population.

关键词： Potentially toxic trace elements(PTEs) Soils Land-use Geo-accumulation index(Igeo) Hazard quotient(HQ) Total carcinogenic risk index(TR) Source apportionment Health risk Agricutural geological survey engineering

Multi-party privacy-preserving decision tree training with a privileged party

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Science China(Information Sciences) 2024年第8期67卷 253-268页

作者： Yiwen TONG Qi FENG Min LUO Debiao HE Key Laboratory of Aerospace Information Security and Trusted Computing Ministry of Education School of Cyber Science and Engineering Wuhan University Shanghai Technology Innovation Centre of Distributed Privacy-Preserving Artificial Intelligence Matrix Elements Technologies Key Laboratory of Computing Power Network and Information Security Ministry of EducationShandong Computer Science Center Qilu University of Technology(Shandong Academy of Sciences)

Currently, a decision tree is the most commonly used data mining algorithm for classification tasks. While a significant number of studies have investigated privacy-preserving decision trees, the methods proposed in these studies often have shortcomings in terms of data privacy breach or efficiency. Additionally,these methods typically only apply to symmetric frameworks, which consist of two or more parties with equal privilege, and are not suitable for asymmetric scenarios where parties have unequal privilege. In this paper,we propose SecureCART, a three-party privacy-preserving decision tree training scheme with a privileged party. We adopt the existing pMPL framework and design novel secure interactive protocols for division,comparison, and asymmetric multiplication. Compared to similar schemes, our division protocol is 93.5–560.4× faster, with the communication overhead reduced by over 90%; further, our multiplication protocol is approximately 1.5× faster, with the communication overhead reduced by around 20%. Our comparison protocol based on function secret sharing maintains good performance when adapted to pMPL. Based on the proposed secure protocols, we implement SecureCART in C++ and analyze its performance using three real-world datasets in both LAN and WAN environments. he experimental results indicate that SecureCART is significantly faster than similar schemes proposed in past studies, and that the loss of accuracy while using SecureCART remains within an acceptable range.

关键词： decision trees privacy protection privileged party secret sharing secure multi-party computation

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Effect of oxide interactions on chromium speciation transformation during simulated municipal solid waste incineration

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Journal of Environmental Sciences 2024年第8期142卷 11-20页

作者： Guodong Zhao Chong Tian Peidong Wu Xuguang Zhang Zhikang Wang Xiaoxiang Chen Zhuo Xiong Yongchun Zhao Junying Zhang State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China National Environmental Protection Engineering Technology Center for Trace elements Pollution Control and Low Carbon Utilization of Coal Huazhong University of Science and TechnologyWuhan 430074China School of Environmental Engineering Wuhan Textile UniversityWuhan 430200China

Chromium released during municipal solid waste incineration(MSWI)is toxic and *** removal of chromium from simulated MSWI flue gas by four sorbents(CaO,bamboo charcoal(BC),powdered activated carbon(PAC),and Al_(2)O_(3))and the effects of four oxides(SiO_(2),Al_(2)O_(3),Fe_(2)O_(3),and CaO)on chromium speciation transformationwere *** results showed that the removal rates of total Cr by the four sorbents were Al_(2)O_(3)

关键词： Cr(Ⅵ)reduction Cr(Ⅲ)oxidation Alkali oxides Acidic oxides Municipal solid waste incineration

Ratio of photosynthetically active radiation to global solar radiation above forest canopy in complex terrain: measurements and analyses based on Qingyuan Ker Towers

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Ecological Processes 2024年第2期 204-217页

作者： Shuangtian Li Qiaoling Yan Tian Gao Xingchang Wang Qingwei Wang Fengyuan Yu Deliang Lu Huaqi Liu Jinxin Zhang Jiaojun Zhu CAS Key Laboratory of Forest Ecology and Silviculture Institute of Applied Ecology Chinese Academy of Sciences Qingyuan Forest CERN National Observation and Research Station Chinese Academy of Sciences CAS-CSI Joint Laboratory of Research and Development for Monitoring Forest Fluxes of Trace Gases and Isotope elements Institute of Applied Ecology Chinese Academy of Sciences (CAS) University of Chinese Academy of Sciences Center for Ecological Research Northeast Forestry University

Background Understanding of the ratio of photosynthetic photon flux density（Qp） to global solar radiation（Rs）(Qp/Rs) is crucial for applying Rsto ecology-related *** studies reported Qp/Rsand its variations based on measurements from a single observatory tower,instead of multi-site-based measurements over complex *** may neglect spatial heterogeneity in the terrain,creating a gap in an understanding of how terrain affects Qp/Rsand how this effect interacts with meteorological *** Here the Qingyuan Ker Towers（three towers in a valley with different terrains:T1,T2,and T3） were utilized to measure Qpand Rsover mountainous forests of Northeast *** airborne LiDAR system was used to generate a digital elevation model,and sky view factor of sectors（SVFs） divided from the field of view of tower's pyranometer was calculated as a topographic factor to explain the variations of Qp/*** The results identified significant differences in Qp/Rsof the three towers at both daily and half-hour scales,with larger differences on clear days than on overcast ***/Rswas positively correlated with SVFsof T1 and T3,while this correlation was negative with that of *** effect of SVFson Qp/Rsinteracted with clearness index,water vapor pressure and solar zenith *** forest-based importance assessment demonstrated that explanation（R2） on Qp/Rswas improved when SVFswas included in the predictor variable set,indicating that incorporating terrain effects enhances the prediction accuracy of Qp/*** improvement in the R2values was more pronounced on clear days than on overcast days,suggesting that the effect of terrain on Qp/Rsdepended on sky *** All findings suggested that Qp/Rsis affected by terrain,and integrating terrain information into existing Qp/Rsmodels is a feasible solution to improve Qp/Rsestimates in mountainous areas.

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来源：博看期刊

Disease and Economic Burden of Kashin-Beck Disease—China,2021

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China CDC weekly 2024年第2期6卷 40-44页

作者： Silu Cui Wenjun Que Zhe Jiao Qing Deng Xufeng Zhang Yanhong Cao Ning Liu Ailin Li Alphonse Sowanou Zhe Li Tuo Wang Yang Li Jun Yu Junrui Pei NHC Key Laboratory of Etiology and Epidemiology(Harbin Medical University) Key Laboratory of Etiology and EpidemiologyEducation Bureau of Heilongjiang ProvinceInstitute of Kashin-Beck Disease ControlCenter for Endemic Disease ControlChinese Center for Disease Control and PreventionHarbin Medical UniversityHarbin CityHeilongjiang ProvinceChina NHC Key Laboratory of Etiology and Epidemiology(Harbin Medical University) Heilongjiang Provincial Key Laboratory of Trace Elements and Human HealthKey Laboratory of Etiology and EpidemiologyEducation Bureau of Heilongjiang ProvinceInstitute of Endemic Fluorosis ControlCenter for Endemic Disease ControlChinese Center for Disease Control and PreventionHarbin Medical UniversityHarbin CityHeilongjiang ProvinceChina

What is already known about this topic?Kashin-Beck disease(KBD)is a chronic and degenerative osteoarthropathy characterized by cartilage *** is an endemic disease that is highly prevalent among the Chinese population and poses a significant health *** is added by this report?This is the first national report on the economic burden of KBD in *** to the data from 2021,KBD has caused significant disease and economic *** most substantial reduction in healthy life expectancy was observed among patients with degree II severity and those aged 60 years and older,resulting in a total indirect economic burden of 112.74 million Chinese Yuan(CNY).What are the implications for public health practice?The results of this study will contribute to informing the development of tailored prevention and control strategies by the *** strategies will include targeted policies and recommendations for appropriate healthcare and financial subsidies,which will be based on the demographic characteristics of the endemic areas.

关键词： prevention degeneration burden

Self-Powered,Long-Durable,and Highly Selective Oil-Solid Triboelectric Nanogenerator for Energy Harvesting and Intelligent Monitoring

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Nano-Micro Letters 2022年第10期14卷 95-107页

作者： Jun Zhao Di Wang Fan Zhang Jinshan Pan Per Claesson Roland Larsson Yijun Shi Division of machine elements Department of Engineering Sciences and MathematicsLuleåUniversity of Technology97187 LuleåSweden Department of Engineering and Design School of Engineering and InformaticsUniversity of SussexBrighton BN19RHUK Division of Surface and Corrosion Science Department of ChemistryKTH Royal Institute of Technology10044 StockholmSweden

Triboelectric nanogenerators(TENGs)have potential to achieve energy harvesting and condition monitoring of oils,the“lifeblood”of ***,oil absorption on the solid surfaces is a great challenge for oil-solid TENG(O-TENG).Here,oleophobic/superamphiphobic O-TENGs are achieved via engineering of solid surface wetting *** designed O-TENG can generate an excellent electricity(with a charge density of 9.1μC m^(−2) and a power density of 1.23 mW m^(−2)),which is an order of magnitude higher than other O-TENGs made from polytetrafluoroethylene and *** also has a significant durability(30,000 cycles)and can power a digital thermometer for self-powered sensor ***,a superhigh-sensitivity O-TENG monitoring system is successfully developed for real-time detecting particle/water contaminants in *** O-TENG can detect particle contaminants at least down to 0.01 wt%and water contaminants down to 100 ppm,which are much better than previous online monitoring methods(particle>0.1 wt%;water>1000 ppm).More interesting,the developed O-TENG can also distinguish water from other contaminants,which means the developed O-TENG has a highly water-selective *** work provides an ideal strategy for enhancing the output and durability of TENGs for oil-solid contact and opens new intelligent pathways for oil-solid energy harvesting and oil condition monitoring.

关键词： Oil Triboelectric nanogenerator Energy harvesting Intelligent monitoring

Discovery of a pair instability supernova ignites excitement about the first stars

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中国科学:物理学、力学、天文学英文版 2023年第9期66卷 198-199页

作者： Timothy C.Beers Department of Physics and Astronomy and JINA Center for the Evolution of the elements University of Notre DameNotre Dame 46556USA

For decades,astronomers have predicted that Pair Instability Supernovae(PISNe)might occur when a massive star(140-260 solar masses,M☉)reaches the end of its life,and suffers a cataclysmic explosion due to the transformation of gamma rays in its interior into pairs of free electrons and positrons,robbing the star of the radiation pressure required to support itself against gravity.

关键词： stars massive supernova

Influence of lubrication,tool steel composition,and topography on the high temperature tribological behaviour of aluminium

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Friction 2021年第1期9卷 155-168页

作者： Justine DECROZANT-TRIQUENAUX Leonardo PELCASTRE Braham PRAKASH Jens HARDELL machine elements Lulea University of TechnologyLulea SE-97187Sweden Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China

The use of high strength aluminium alloys,such as 6 XXX and 7 XXX series,is continuously increasing for automotive applications in view of their good strength-to-weight *** formability at room temperature is limited and they are thus often formed at high temperatures to enable production of complex *** challenges during hot forming of aluminium are the occurrence of severe adhesion and material transfer onto the forming *** negatively affects the tool life and the quality of the produced *** general,the main mechanisms involved in the occurrence of material transfer of aluminium alloys at high temperature are still not clearly ***,this study is focussed on understanding of the friction and wear behaviour during interaction of Al6016 alloy and three different tool steels in as-received and polished *** tribotests were carried out under dry and lubricated conditions,with two distinct lubricants,using a reciprocating friction and wear *** worn surfaces were analysed using scanning electron microscopy(SEM)and energy dispersive X-ray spectroscopy(EDS).The results showed a high dependence of friction and wear behaviour on the tool steel roughness as well as on the stability of the lubricant *** were found to develop in the contact zone and their capacity to improve the tribological behaviour is seen to be drastically impacted by the surface roughness of the tool *** the tribolayers failed,severe adhesion took place and led to high and unstable friction as well as material transfer to the tool steel.

关键词： friction wear high temperature tribology aluminium lubrication tribolayer

Numerical prediction of the frictional losses in sliding bearings during start-stop operation

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Friction 2021年第3期9卷 583-597页

作者： Florian KÖNIG Christopher SOUS Georg JACOBS Institute for machine elements and Systems Engineering Rheinisch-Westfälische Technische Hochschule Aachen UniversitySchinkelstraße 10Aachen 52062Germany

With the increased use of automotive engine start-stop systems,the numerical prediction and reduction of frictional losses in sliding bearings during starting and stopping procedures has become an important *** engineering practice,numerical simulations of sliding bearings in automotive engines are performed with statistical asperity contact models with empirical values for the necessary surface *** aim of this study is to elucidate the applicability of these approaches for the prediction of friction in sliding bearings subjected to start-stop *** this purpose,the friction performance of sliding bearings was investigated in experiments on a test rig and in transient mixed elasto-hydrodynamic simulations in a multi-body simulation environment(mixed-EHL/MBS).In mixed-EHL/MBS,the extended Reynold’s equation with flow factors according to Patir and Cheng has been combined on the one hand with the statistical asperity contact model according to Greenwood and Tripp and on the other hand with the deterministic asperity contact model according to *** detailed comparison of simulation and experimental results clarifies that the application of statistical asperity contact models with empirical values of the necessary inputs leads to large deviations between experiment and *** actual distribution and position of surface roughness,as used in deterministic contact modelling,is necessary for a reliable prediction of the frictional losses in sliding bearings during start-stop operation.

关键词： sliding bearing friction wearing-in contact model,mixed elasto-hydrodynamic simulation