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Modeling environmental sensitivity and risk assessment of PAHs in sediments along two marine coastal areas in Egypt

Petroleum Research 2024年第1期9卷 125-142页

作者： Muhammad A.El-Alfy National institute of oceanography and Fisheries NIOFCairoEgypt

Modeling the environmental sensitivity index(ESI)is vital in the planning and management processes,especially along the coastal *** main objectives of the study were to define the main sources of polycyclic aromatic hydrocarbons(PAHs),establish an ESI model,and measure the risk of PAHs on humans and the environment using various *** methodology of the research involved analyzing PAHs according to the EPA 550 methodology in sediments of the coastline in two important coastline areas in Egypt,namely the Gulf of Suez and the Mediterranean Sea,modeling the sensitivity of PAHs using ArcGIS 10.5 by integrating different physical,biological,and land use/cover factors,identifying the sources,and performing a risk *** sediment samples were collected from each *** produced sensitivity map could explain the highly sensitive areas along the Mediterranean Sea and Gulf of Suez coastlines(especially areas that were near drains'outlets,industrial sites,and sea ports).The highest mean PAH concentrations were Acenaphthylene and Fluorine in the Mediterranean Sea and Suez Gulf,***'s obvious that the individual PAH concentrations were within the ERL,ERM,and PEL threshold limits,indicating no adverse biological *** ratios of BaA/BaA+Chy,Flu/Flu+Py,and Ant/Ant+Phe gave an indication that most PAH sources were petrogenic(63.64%)and others(3..3.%)were from petroleum *** principle component analysis(PCA)indicated a diverse correlation among the isomer ratios and LU/LC *** carcinogenic risk values were in the very low category(<10^(-6))for both children and *** most significant contributors to carcinogenicity were IP and BkFlu in the Mediterranean Sea and Suez Gulf,*** sources of carbon in seawater,especially with climatic change,may impact the aquatic environment and have impacts on organisms and coral *** it is highly recommended to keep shorelines and seawater free of oil spillage act

关键词： Polycyclic aromatic hydrocarbons(PAHs) Modeling Sensitivity Gulf of Suez And Mediterranean sea

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Determinants of saturation magnetic flux density in Fe-based metallic glasses: insights from machine-learning models

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Rare Metals 2024年第10期43卷 5256-5267页

作者： Jie Xiong Bo-Wen Bai Hao-Ran Jiang Angeles Faus-Golfe Materials Genome institute Shanghai University institute of Special Environments physical Sciences Harbin Institute of Technology Laboratoire de Physique des 2 Infinis Irene Joliot-Curie (IJCLab) CNRS-IN2P3Universite′Paris-Saclay

Fe-based metallic glasses have garnered significant attention due to their low coercivity force and core loss. Enhancing the saturation magnetic flux density(Bs) of Fe-based metallic glasses is crucial for their industry applications. This work constructed a dataset comprising3.0 training data and 157 test data. The support vector regression model surpassed the tree-based ensemble models in the test set and demonstrated comparable accuracy to the tree-based ensemble models in the training set. Additionally, we proposed an indicator for Bsbased on symbolic regression. This newly proposed indicator exhibits a Pearson correlation coefficient exceeding 0.92 with Bs. The present work provides a simple and accurate formula for predicting the Bsof Fe-based amorphous alloys, demonstrating the effectiveness of machine learning approaches in discovering novel soft magnetic materials.

关键词： Fe-based metallic glasses Machine learning Saturation magnetic flux density Symbolic regression

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Enhancing Tropical Cyclone Intensity Estimation from Satellite Imagery through Deep Learning Techniques

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Journal of Meteorological Research 2024年第4期38卷 652-663页

作者： Wen YANG Jianfang FEI Xiaogang HUANG Juli DING Xiaoping CHENG College of Meteorology and oceanography National University of Defense TechnologyChangsha 410008 Beijing institute of Applied Meteorology Beijing 100029

This study first utilizes four well-performing pre-trained convolutional neural networks(CNNs) to gauge the intensity of tropical cyclones(TCs) using geostationary satellite infrared(IR) *** models are trained and tested on TC cases spanning from 2004 to 2022 over the western North Pacific *** enhance the models performance,various techniques are employed,including fine-tuning the original CNN models,introducing rotation augmentation to the initial dataset,temporal enhancement via sequential imagery,integrating auxiliary physical information,and adjusting *** optimized CNN model,i.e.,visual geometry group network(VGGNet),for TC intensity estimation is ultimately *** applied to the test data,the model achieves a relatively low mean absolute error(MAE) of 4.05 m s~(-1).To improve the interpretability of the model,the SmoothGrad combined with the Integrated Gradients approach is *** analyses reveal that the VGGNet model places significant emphasis on the distinct inner core region of a TC when estimating its ***,it partly takes into account the configuration of cloud systems as input features for the model,aligning well with meteorological *** several improvements made to this model's performance offer valuable insights for enhancing TC intensity forecasts through deep learning.

关键词： tropical cyclone intensity deep learning satellite imagery

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Universal Machine Learning Kohn–Sham Hamiltonian for Materials

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Chinese Physics Letters 2024年第7期41卷 95-110页

作者：钟阳于宏宇杨吉辉郭星宇向红军龚新高 Key Laboratory of Computational physical Sciences(Ministry of Education) Institute of Computational Physical SciencesState Key Laboratory of Surface Physicsand Department of PhysicsFudan UniversityShanghai 200433China Shanghai Qi Zhi institute Shanghai 200030China

While density functional theory(DFT)serves as a prevalent computational approach in electronic structure calculations,its computational demands and scalability limitations ***,leveraging neural networks to parameterize the Kohn-Sham DFT Hamiltonian has emerged as a promising avenue for accelerating electronic structure *** advancements,challenges such as the necessity for computing extensive DFT training data to explore each new system and the complexity of establishing accurate machine learning models for multi-elemental materials still *** these hurdles,this study introduces a universal electronic Hamiltonian model trained on Hamiltonian matrices obtained from first-principles DFT calculations of nearly all crystal structures on the Materials *** demonstrate its generality in predicting electronic structures across the whole periodic table,including complex multi-elemental systems,solid-state electrolytes,Moir´e twisted bilayer heterostructure,and metal-organic ***,we utilize the universal model to conduct high-throughput calculations of electronic structures for crystals in GNoME datasets,identifying 3.40 crystals with direct band gaps and 5109 crystals with flat *** offering a reliable efficient framework for computing electronic properties,this universal Hamiltonian model lays the groundwork for advancements in diverse fields,such as easily providing a huge data set of electronic structures and also making the materials design across the whole periodic table possible.

关键词： Hamiltonian utilize twisted

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First-principles study of electronic and magnetic properties of Fe atoms on Cu_(2)N/Cu(100)

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Chinese Physics B 2024年第8期33卷 498-503页

作者：陈佳乐胡军 institute of High Pressure Physics School of Physical Science and TechnologyNingbo UniversityNingbo 315211China

First-principles calculations were conducted to investigate the structural,electronic,and magnetic properties of single Fe atoms and Fe dimers on Cu_(2)N/Cu(100).Upon adsorption of an Fe atom onto Cu_(2)N/Cu(100),robust Fe-N bonds form,resulting in the incorporation of both single Fe atoms and Fe dimers within the surface Cu_(2)N *** partial occupancy of Fe-3. orbitals lead to large spin moments on the Fe ***,both single Fe atoms and Fe dimers exhibit in-plane magnetic anisotropy,with the magnetic anisotropy energy(MAE)of an Fe dimer exceeding twice that of a single Fe *** magnetic anisotropy can be attributed to the predominant contribution of the component along the x direction of the spin-orbital coupling ***,the formation of Fe-Cu dimers may further boost the magnetic anisotropy,as the energy levels of the Fe-3. orbitals are remarkably influenced by the presence of Cu *** study manifests the significance of uncovering the origin of magnetic anisotropy in engineering the magnetic properties of magnetic nanostructures.

关键词： magnetic nanostructures magnetic anisotropy spin–orbital coupling ultrathin substrate

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Surface modification by ligand growth strategy for dense copper bismuth film as photocathode to enhance hydrogen production activity

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Frontiers in Energy 2024年第1期18卷 89-100页

作者： Zhouzhou WANG Qingwei WU Jieming WANG Ying YU institute of Nanoscience and Nanotechnology College of Physical Science and TechnologyCentral China Normal UniversityWuhan 430079China

Hydrogen production from photoelectrochemical(PEC)water splitting has been regarded as a promising way to utilize renewable and endless solar ***,semiconductor film grown on photoelectrode suffers from numerous challenges,leading to the poor PEC ***,a straightforward sol-gel method with the ligand-induced growth strategy was employed to obtain dense and homogeneous copper bismuthate photocathodes for PEC hydrogen evolution *** various characterizations,it was found that the nucleation and surface growth of CuBi_(2)O_(4)layer induced by 2-methoxyethanol ligand(2-CuBi_(2)O_(4))demonstrated a decent crystallinity and coverage,as well as a large grain size and a low oxygen vacancy concentration,leading to the good ability of light absorption and carrier ***,under simulated sunlight irradiation(AM1.5G,100 mW/cm^(2)),the 2-CuBi_(2)O_(4)photocathode achieved an enhanced photocurrent density of−1.3. mA·cm^(−2)at 0.4 V versus the reversible hydrogen electrode and a promising applied bias photon-to-current efficiency of 0.586%.This surface modification by ligand growth strategy will shed light on the future design of advanced photoelectrodes for PEC water splitting.

关键词： copper bismuthate photocathode ligand growth strategy dense film PEC

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Four-to Six-Year Periodic Variation of Arctic Sea-Ice Extent and Its Three Main Driving Factors

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Advances in Atmospheric Sciences 2024年第10期41卷 1999-2010页

作者： Ping CHEN Jinping ZHAO Xiaoyu WANG institute of Oceanographic Instrumentation Qilu University of Technology(Shandong Academy of Sciences)Qingdao 266000China College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266000China Frontiers Science Center for Deep Ocean Multispheres and Earth SystemKey Laboratory of Physical OceanographyOcean University of ChinaQingdao 266000China

Besides the rapid retreating trend of Arctic sea-ice extent(SIE),this study found the most outstanding low-frequency variation of SIE to be a 4-6-year periodic *** a clustering analysis algorithm,the SIE in most ice-covered regions was clustered into two special regions:Region-1 around the Barents Sea and Region-2 around the Canadian Basin,which were located on either side of the Arctic Transpolar *** 4-6-year periodic variation in these two regions was identified using a novel method called“running linear fitting algorithm”.The rate of temporal variation of the Arctic SIE was related to three driving factors:the regional air temperature,the sea-ice areal flux across the Arctic Transpolar Drift,and the divergence of sea-ice *** 4-6-year periodic variation was found to have always been present since 1979,but the SIE responded to different factors under heavy and light ice conditions divided by the year *** joint contribution of the three factors to SIE variation exceeded 83.and 59%in the two regions,respectively,remarkably reflecting their dynamic *** is proven that the process of El Niño-Southern Oscillation(ENSO)is closely associated with the three factors,being the fundamental source of the 4-6-year periodic variations of Arctic SIE.

关键词： sea-ice extent periodic variation air temperature sea-ice areal flux Arctic Transpolar Drift ice-drift divergence ENSO

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Needs and challenges of optical atmospheric monitoring on the background of carbon neutrality in China

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 49-62页

作者： Wenqing Liu Chengzhi Xing Anhui institute of Optics and Fine Mechanics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 23001China

The achievement of the targets of coordinated control of PM2.5 and O3.and the carbon peaking and carbon neutrality depend on the development of pollution and greenhouse gas monitoring *** monitoring technology,based on its technical characteristics of high scalability,high sensitivity and wide-targets detection,has obvious advantages in pollution/greenhouse gases monitoring and has become an important direction in the development of environmental monitoring *** present,a system of environmental optical monitoring technology with differential optical absorption spectroscopy(DOAS),cavity ring-down spectroscopy(CRDS),light detection and ranging(LIDAR),laser heterodyne spectroscopy(LHS),tunable diode laser absorption spectroscopy(TDLAS),fourier transform infrared spectroscopy(FTIR)and fluorescence assay by gas expansion(FAGE)as the main body has been ***,with the promotion of“reduction of pollution and carbon emissions”strategy,there have been significant changes in the sources of pollution/greenhouse gases,emission components and emission concentrations,which have put forward new and higher requirements for the development of monitoring *** the future,we should pay more attention to the development of new optical monitoring techniques and the construction of stereoscopic monitoring system,the interdisciplinarity(among mathematics,physics,chemistry and biology,etc.),and the monitoring of greenhouse gases and research on atmospheric chemistry.

关键词： Pollution Greenhouse gas Optical atmospheric monitoring Needs and challenges

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Robust asymmetric Cherenkov radiation in tilted anisotropic medium

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 46-51页

作者： Shuwen Xue Yadong Xu Linkang Han Zhi Ning Chen Qiaoliang Bao Shan Zhu Huanyang Chen institute of Electromagnetics and Acoustics and Department of Physics College of Physical Science and TechnologyJiujiang Research InstituteXiamen UniversityXiamen 361005China School of physical Science and Technology Institute of Theoretical and Applied PhysicsSoochow UniversitySuzhou 215006China Department of Electrical and Computer Engineering National University of SingaporeSingapore 8117583Singapore institute of Energy Materials Science(IEMS) University of Shanghai for Science and TechnologyShanghai 200093China

Cherenkov radiation(CR)is available for a wide variety of terahertz(THz)radiation sources,but its efficiency is deeply affected by intrinsic *** find that if the tilted angle(α)of anisotropic material and radiation angle(θ)meet the condition ofθ+α=π/2,the intensity of radiation fields for the charged particle bunch(CPB)moving from left to right cannot be influenced by intrinsic losses,which means long-distance radiation can be ***,we observe an asymmetric CR when the CPB moves from the opposite *** addition,we select natural van der Waals(vd W)materialα-MoO3.s an example,further confirming that the radiation field can reach the far field and the asymmetric CR radiation can also be *** wonderful properties with long-distance radiation will extend the application of CR to a certain extent for future design and fabrication.

关键词： asymmetric Cherenkov radiation intrinsic losses long-distance radiation

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Single thiolate replacement of metal nanoclusters

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Science China Chemistry 2024年第2期67卷 523-528页

作者： Ambreen Ambreen Yue Zhou Wanmiao Gu Qing You Liang Fang Guoqing Bian Nan Yan Nan Xia Zhikun Wu Key Laboratory of Materials Physics Anhui Key Laboratory of Nanomaterials and NanotechnologyInstitute of Solid State PhysicsHefei Institutes of Physical Science(HFIPS)Chinese Academy of SciencesHefei230031China University of Science and Technology of China Hefei230601China institute of physical Science and Information Technology Anhui UniversityHefei230601China

Surface thiolates play important roles in evincing the structures and properties of thiolated metal nanoclusters—one type of recently emerging inorganic-organic hybrids,and thus the thiolate substitution,especially single thiolate substitution,is highly desirable for subtly tailoring the structures and properties of metal ***,such a single-thiolate substituting is challenging,and its influence on the metal-metal and metal-sulfur bonds remains mysterious due to the absence of the singlethiolate-substituted ***,we developed a combined method,concurrently synthesized the single-thiolate-substituted nanocluster and its parent nanocluster,and successfully resolved their structures by single crystal X-ray crystallography,which reveals that the single thiolate substitute has an obvious influence on the metal-metal and metal-sulfur bond lengths although it has no effect on the absorption ***,the metal-metal and metal-sulfur bonds show various thermal extensibility and even the negative thermal expansion phenomena of the Au–S bond were observed in the single-thiolate-substituted *** bond length-related stability was also ***,this study highlights a novel synthesis method and offers novel structural insights and an in-depth structure-property correlation of thiolated metal nanoclusters.

关键词： metal nanoclusters single thiolate replacement thermal expansion stability intercluster interaction

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