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Profiles,exposure assessment and expanded screening of PAHs and their derivatives in one petroleum refinery facility of China

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Journal of Environmental Sciences 2025年第1期147卷 550-560页

作者： ning Wang Fengjiao Jiang lin Xu Yaqi Cai School of Municipal and Environmental Engineering Shandong Jianzhu UniversityJinan 250101China Resource and Environmental Innovation Institute Shandong Jianzhu UniversityJinan 250101China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Environment Hangzhou Institute for Advanced StudyUCASHangzhou 330106China Hubei Key Laboratory of Environmental and Health Effects of Persistence Toxic Substances Institute of Environment and HealthJianghan UniversityWuhan 430056China

This study investigated environmental distribution and human exposure of polycyclic aromatic hydrocarbons(PAHs)and their derivatives in one Chinese petroleum refinery *** was found that,following with high concentrations of 16 EPA PAHs(∑Parent-PAHs)in smelting subarea of studied petroleum refinery facility,total derivatives of PAHs[named as XPAHs,including nitro PAHs(NPAHs),chlorinated PAHs(Cl-PAHs),and brominated PAHs(Br-PAHs)]in gas(mean=1.57×10^(4)ng/m^(3)),total suspended particulate(TSP)(mean=4.33×10^(3) ng/m^(3))and soil(mean=4.37×10^(3) ng/g)in this subarea had 1.76-6.19 times higher levels than those from other subareas of this facility,surrounding residential areas and reference areas,indicating that petroleum refining processes would lead apparent derivation of ***,compared with those in residential and reference areas,gas samples in the petrochemical areas had higher∑NPAH/∑PAHs(mean=2.18),but lower∑Cl-PAH/∑PAHs(mean=1.43×10^(-1))and∑Br-PAH/∑PAHs ratios(mean=7.49×10^(-2)),indicating the richer nitrification of PAHs than chlorination during petrochemical *** occupational exposure to PAHs and XPAHs in this petroleum refinery facility were 24-343 times higher than non-occupational exposure,and the ILCR(1.04×10^(-4))for petrochemical workers was considered to be potential high ***,one expanded high-resolution screening through GC Orbitrap/MS was performed for soils from petrochemical area,and another 35 PAHs were found,including alkyl-PAHs,phenyl-PAHs and other species,indicat-ing that profiles and risks of PAHs analogs in petrochemical areas deserve further expanded investigation.

关键词： Polycyclic aromatic hydrocarbons(PAHs) Derivatives Petroleum refinery Human exposure Non-targeted screening

静止条件下的月球车INS/CNS自主初始化方法

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中国惯性技术学报 2014年第2期12卷 141-148页

作者：宁晓琳刘玲玲惯性技术重点实验室北京100191 新型惯性仪表与导航系统技术国防重点学科实验室北京100191 北京航空航天大学仪器科学与光电工程学院北京100191

月球车工作前自身初始位置和姿态的确定对提高其导航能力具有重要作用,这一过程也称为初始化,初始化精度将严重影响其后续导航性能。针对月面特殊环境,现有的应用于地面环境的初始化方法不再适用这一问题,提出了一种静止条件下的月球车I... 详细信息

月球车工作前自身初始位置和姿态的确定对提高其导航能力具有重要作用,这一过程也称为初始化,初始化精度将严重影响其后续导航性能。针对月面特殊环境,现有的应用于地面环境的初始化方法不再适用这一问题,提出了一种静止条件下的月球车INS/CNS自主初始化方法。该方法分为粗初始化和精初始化两个阶段,粗初始化主要为精初始化提供初始参数。精初始化则综合利用惯性导航解算得到的水平速度、星光方位矢量和天体高度量测信息,并在考虑加速度计偏置引起的天体高度误差的基础上建立了精确的天体高度量测方程,精确估计月球车的初始位置和姿态。半物理仿真实验表明当陀螺漂移为0.1(°)/h、加速度计偏置为10?g、星敏感器精度为3″时,采用所提方法的初始位置估计精度优于30 m,初始姿态估计精度优于10″,是一种非常有效的月球车自主初始化方法。

关键词：月球车自主初始化惯性导航天文导航

RJMCMC粒子滤波方法在月球探测器自主天文导航中的应用

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宇航学报 2005年第B10期26卷 39-44页

作者：宁晓琳房建成北京航空航天大学第五研究室北京100083

天文导航系统是典型的非线性和噪声非高斯分布的系统。针对传统的扩展卡尔曼滤波不适于非线性和噪声非高斯分布的系统,和一般粒子滤波存在的粒子退化等问题,提出了一种将RJMCMC(可逆跳转马尔可夫链蒙特卡罗)算法应用于月球探测器自主天... 详细信息

天文导航系统是典型的非线性和噪声非高斯分布的系统。针对传统的扩展卡尔曼滤波不适于非线性和噪声非高斯分布的系统,和一般粒子滤波存在的粒子退化等问题,提出了一种将RJMCMC(可逆跳转马尔可夫链蒙特卡罗)算法应用于月球探测器自主天文导航粒子滤波器中的新方法。计算机仿真结果显示了该方法在加快收敛速度、提高导航定位精度和自适应调整粒子个数方面的有效性和可行性。

关键词：月球探测器自主天文导航粒子滤波 RJMCMC

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一种深空天文测角导航中的星历误差抑制方法

宇航学报 2019年第12期40卷 1412-1421页

作者：宁晓琳晁雯杨雨青北京航空航天大学仪器科学与光电工程学院

以火星探测器为例,提出一种以星光角距/时间差分星光角距作为量测量的星历误差抑制方法,分析了火卫一星历误差对导航精度的影响,建立了火卫一时间差分星光角距的量测模型。通过将火星星光角距和火卫一星光角距相结合,发挥了两种量测的优... 详细信息

以火星探测器为例,提出一种以星光角距/时间差分星光角距作为量测量的星历误差抑制方法,分析了火卫一星历误差对导航精度的影响,建立了火卫一时间差分星光角距的量测模型。通过将火星星光角距和火卫一星光角距相结合,发挥了两种量测的优势,实现了对火卫一星历误差的抑制。仿真结果表明,基于星光角距/时间差分星光角距天文导航方法的位置误差是传统基于星光角距天文导航方法的64%,是基于时间差分星光角距导航方法的58%。此外,还分析了导航恒星个数、火星敏感器精度、火卫一敏感器精度、星历误差大小和滤波周期对导航性能的影响。

关键词：深空探测器天文测角导航星历误差时间差分

Unmasking Social Robots’Camouflage:A GNN-Random Forest Framework for Enhanced Detection

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Computers, Materials & Continua 2025年第1期82卷 467-483页

作者： Weijian Fan Chunhua Wang xiao Han Chichen lin School of Data Science and Intelligent Media Communication University of ChinaBeijing100024China School of Computer and Cyber Sciences Communication University of ChinaBeijing100024China Institute of Communication Studies Communication University of ChinaBeijing100024China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China

The proliferation of robot accounts on social media platforms has posed a significant negative impact,necessitating robust measures to counter network anomalies and safeguard content *** robot detection has emerged as a pivotal yet intricate task,aimed at mitigating the dissemination of misleading *** graphbased approaches have attained remarkable performance in this realm,they grapple with a fundamental limitation:the homogeneity assumption in graph convolution allows social robots to stealthily evade detection by mingling with genuine human *** unravel this challenge and thwart the camouflage tactics,this work proposed an innovative social robot detection framework based on enhanced HOmogeneity and Random Forest(HORFBot).At the core of HORFBot lies a homogeneous graph enhancement strategy,intricately woven with edge-removal techniques,tometiculously dissect the graph intomultiple revealing ***,leveraging the power of contrastive learning,the proposed methodology meticulously trains multiple graph convolutional networks,each honed to discern nuances within these tailored *** culminating stage involves the fusion of these feature-rich base classifiers,harmoniously aggregating their insights to produce a comprehensive detection *** experiments on three social robot detection datasets have shown that this method effectively improves the accuracy of social robot detection and outperforms comparative methods.

关键词： Social robot detection graph neural networks random forest homophily heterophily

Magnetically-responsive phase change thermal storage materials:Mechanisms,advances,and beyond

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Journal of Energy Chemistry 2025年第2期101卷 485-510页

作者： Yan Gao Yang Li Jinjie lin Panpan Liu xiao Chen Ge Wang Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule & Structure Construction School of Materials Science and Engineering University of Science and Technology Beijing School of Physics and Astronomy Beijing Normal University Shunde Graduate School University of Science and Technology Beijing

Rapid advances in thermal management technology and the increasing need for multi-energy conversion have placed stringent energy efficiency requirements on next-generation shape-stable composite phase change materials(PCMs).Magnetically-responsive phase change thermal storage materials are considered an emerging concept for energy storage systems,enabling PCMs to perform unprecedented functions(such as green energy utilization,magnetic thermotherapy,drug release,etc.).The combination of multifunctional magnetic nanomaterials and PCMs is a milestone in the creation of advanced multifunctional composite ***,a timely and comprehensive review of composite PCMs based on magnetic nanoparticle modification is still ***,we furnish an exhaustive exposition elucidating the cutting-edge advancements in magnetically responsive composite *** delve deeply into the multifarious roles assumed by distinct nanoparticles within composite PCMs of varying dimensions,meticulously scrutinizing the intricate interplay between their architectures and thermophysical ***,we prognosticate future research trajectories,delineate alternative stratagems,and illuminate prospective *** review is intended to stimulate broader academic interest in interdisciplinary fields and provide valuable insights into the development of next-generation magnetically-responsive composite PCMs.

关键词： Magnetic nanoparticles Magnetic-thermal conversion Phase change materials Response mechanism Thermal energy storage

Exposure of individuals aged 18-44 years to personal care products in Beijing,China:Exposure profiles,possible influencing factors,and risk assessment

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Journal of Environmental Sciences 2025年第2期148卷 691-701页

作者： Xu Zhang linxue Han Qi Sun xiaochen Wang xiaojian Hu xiao lin Ying Zhu China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijing 100021China The Bureau for Health Inspection and Supervision of Haidian District Beijing 100037China

Personal care products(PCPs)are a class of emerging pollutants that have attracted public concern owing to their harmful effects on humans and the *** data is valuable for insight the levels of PCPs in the human body and can be crucial for identifying potential health *** gain a better understanding of timely exposure profiles and health risk of reproductive-age population to PCPs,we determined six parabens,six benzophenone-type ultraviolet filters,and three disinfectants in 256 urine samples collected from young adults aged 18-44 years in Beijing,*** urinary levels of benzophenone-3(BP-3)and 4-hydroxybenzophenone(4-OHBP)were significantly higher in summer compared to winter,suggesting these compounds have different seasonal usage ***,the total concentration of 15 PCPs in female was 430 ng/mL,approximately two times higher than that in male.P-chloro-m-xylenol(PCMX),as a new type of antibacterial agent,has the greatest level among all target analytes,indicating the increasingly use of this antibacterial alternative *** potential influencing factors that lead to the elevated exposure level of PCPs were *** 19%of the target population had a high hazard index value(greater than 1)which was attributed to exposure to propyl paraben(PrP),benzophenone-1(BP-1),BP-3 and PCMX,indicating that PCPs may pose a relatively high exposure risk at environmental levels that should be a cause for concern.

关键词： Personal care products Hazard quotient Risk assessment Exposure patterns Urine

High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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Tungsten 2025年第1期7卷 120-136页

作者： Zao-Ming Wu lin He lin-Sen Ye xiao-Feng Yang Jia-Jia Zhang Hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

New poly-types of LPSO structures in a non-equilibrium Mg_(97)Zn_(1)Y_(1.6)Ca_(0.4)alloy

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China Foundry 2025年第1期22卷 83-89页

作者： Qian-qian Jin Zi-hui Tang Wen-long xiao Xiu-yu Qu Xu-hao Han lin Mei xiao-hong Shao Xiu-liang Ma School of Biological and Chemical Engineering Guangxi University of Science and TechnologyLiuzhou 545006GuangxiChina Center for the Structure of Advanced Matter School of Electronic EngineeringGuangxi University of Science and TechnologyLiuzhou 545006GuangxiChina Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Bay Area Center for Electron Microscopy Songshan Lake Materials LaboratoryDongguan 523808GuangdongChina

In this study,a comprehensive analysis of microstructural features,morphology,crystal structures,and interface structures of long-period stacking ordered(LPSO)structures in a non-equilibrium Mg_(97)Zn_(1)Y_(16)Ca_(0.4)alloy cast in a steel mold was carried *** addition of Ca element plays an important role in the refinement of LPSO *** result reveals new poly-types including 20H F2F2F4,60R(F2F3F3)_(3),and 66H F2F3F3F2(F6)_(4)featuring a 6-Mg structure,alongside the prevalent 18R and 14H LPSO *** incoherent interface between 20H and the Mg matrix is split into two dislocation arrays,leading to the formation of a segment of 60R_(1).Moreover,the superstructure 116L,designated as(F2)_(18)F4,is formed through the ordered distribution of F4 stacking faults in 18R.

关键词： LPSO structures crystal structure Mg alloys heterogeneous interface