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某工业场地土壤砷的空间分布及As(Ⅲ)迁移规律研究

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土壤通报 2024年第2期55卷 502-512页

作者：左玉涛孔文亮代义彬 SEIdOU c.d. 王铁军天津大学地球系统科学学院表层地球系统科学研究院天津300072 天津北大港湿地自然保护区管理中心天津300270 天津大学天津环渤海滨海地球关键带国家野外科学观测研究站天津300072 天津大学天津市环渤海关键带科学与可持续发展重点实验室天津300072

[目的]旨在掌握某工业场地土壤中砷(As)的空间分布特征并揭示其迁移规律,为该工业场地土壤As污染防治提供数据与理论基础。[方法]本文选取葫芦岛市某工业场地为研究区,首先统计分析了场地内土壤As含量的空间分布特征,并比较了等温与动... 详细信息

[目的]旨在掌握某工业场地土壤中砷(As)的空间分布特征并揭示其迁移规律,为该工业场地土壤As污染防治提供数据与理论基础。[方法]本文选取葫芦岛市某工业场地为研究区,首先统计分析了场地内土壤As含量的空间分布特征,并比较了等温与动态吸附两种获取土壤中As(Ⅲ)吸附参数的实验方法的特点与适用性,最终利用HYdRUS-1d模型反演计算了As(Ⅲ)在供试土壤中的d_(L)、K、α、β等迁移参数。[结果]场地土壤As浓度水平分布具有显著差异,在垂向上主要富集于40 cm深度内,且随深度增加而降低。等温吸附实验的结果表明:土样中As(Ⅲ)的平衡固相浓度随液相浓度增加呈非线性增长趋势,Langmuir模型(R^(2)=0.988)对实测数据的拟合效果优于Henry和Freundlich模型。动态吸附实验结果展示了As(Ⅲ)相对浓度完全穿透土柱所需的污染液体积随As(Ⅲ)初始浓度的增加而减少的规律;HYdRUS-1d反演结果表明三类吸附模型中,Langmuir模型(R^(2)=0.990)更适用于模拟土样中As(Ⅲ)的动态吸附过程。相较于等温吸附实验,使用动态吸附实验模拟As(Ⅲ)迁移行为更接近其在土壤中的真实迁移过程。[结论]该场地中的As污染来源于工业活动,主要集中在浅层土壤;土壤中As(Ⅲ)的迁移行为表现为非线性过程,较高的初始浓度将加速As(Ⅲ)的垂向迁移。动态吸附实验方法应优先应用于土壤As迁移过程及其参数获取的研究中。

关键词：土壤砷工业污染等温吸附动态吸附 HYdRUS-1d

Near resonance vibration isolation on a levered-dual response(LEdAR)coulomb-damped system by differential preloads/offsets in linear springs

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1033-1050页

作者： T.I.TOLUWALOJU c.K.THEIN d.HALIM department of Mechanical Materials and Manufacturing EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100Zhejiang ProvinceChina Nottingham Ningbo china Beacons of Excellence Research and Innovation Institute University of Nottingham Ningbo ChinaNingbo 315048Zhejiang ProvinceChina

The levered-dual response(LEdAR)coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear *** takes the advantages of both the preloads/offsets in linear springs and the guiderail friction for realizing different levels of vibration *** isolation capacities are investigated on the strategies with both the horizontal and vertical guiderails,with the horizontal rail only,and without *** compressive preloads generally result in the consumption of most of the initial excitation energy so as to overcome the potential *** isolation onsets at the frequency ratio of 1∓0.095 on the left-hand side(LHS)and the right-hand side(RHS)of the lever are relative to the load plate *** observed near resonant isolation thus makes the LEdAR system a candidate for the isolation of the mechanical systems about resonance while opening a path for simultaneous harvesterisolation functions and passive functions at extreme frequencies.

关键词： lever ratio coulomb damping preload tension/compression isolation band/depth offset potential

Prescribed-Time Nash Equilibrium Seeking for Pursuit-Evasion Game

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IEEE/cAA Journal of Automatica Sinica 2024年第6期11卷 1518-1520页

作者： Lei Xue Jianfeng Ye Yongbao Wu Jian Liu d.c.Wunsch Key Laboratory of Measurement and control of complex Systems of Engineering Ministry of EducationNanjing 210096 School of Automation Southeast UniversityNanjing 210096China department of Electrical and computer Engineering Missouri University of Science and TechnologyRollaMO 65409 USA IEEE

dear Editor,This letter is concerned with prescribed-time Nash equilibrium(PTNE)seeking problem in a pursuit-evasion game(PEG)involving agents with second-order *** order to achieve the prior-given and user-defined convergence time for the PEG,a PTNE seeking algorithm has been developed to facilitate collaboration among multiple pursuers for capturing the evader without the need for any global ***,it is theoretically proved that the prescribedtime convergence of the designed algorithm for achieving Nash equilibrium of ***,the effectiveness of the PTNE method was validated by numerical simulation results.A PEG consists of two groups of agents:evaders and *** pursuers aim to capture the evaders through cooperative efforts,while the evaders strive to evade *** is a classic noncooperative *** has attracted plenty of attention due to its wide application scenarios,such as smart grids[1],formation control[2],[3],and spacecraft rendezvous[4].It is noteworthy that most previous research on seeking the Nash equilibrium of the game,where no agent has an incentive to change its actions,has focused on asymptotic and exponential convergence[5]-[7].

关键词： seeking prescribed convergence

How can Practitioners Support citizen Volunteers in disaster Risk Reduction? Insight from “Good and Ready” in Aotearoa New Zealand

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International Journal of disaster Risk Science 2024年第03期15卷 374-387页

作者： Lo?c Le dé Steve Ronoh Ei Mon Thinn Kyu Brigitte Rive School of Public Health and Interdisciplinary Studies Auckland University of Technology Pacific Health Research centre Auckland University of Technology New Zealand Red cross

Global and national policy frameworks emphasize the importance of people's participation and volunteers' role in disaster risk reduction. While research has extensively focused on volunteers in disaster response and recovery, less attention has been paid on how organizations involved in disaster risk management can support volunteers in leading and coordinating communitybased disaster risk reduction. In 2019, the New Zealand Red cross piloted the Good and Ready initiative in Auckland,Aotearoa New Zealand, with the objective to empower local people in resilience building with a focus on volunteers and community participation. This research examined the positive and negative outcomes of Good and Ready and investigated volunteers' experiences in the disaster resilience initiative. It involved the c.d.sign of a questionnaire-based survey using participatory methods with Good and Ready volunteers, the dissemination of the survey to gather volunteers' viewpoints, and a focus group discussion with participatory activities with Red cross volunteers. The findings highlight that a key challenge lies in finding a balance between a program that provides flexibility to address contextual issues and fosters communities' ownership, versus a prescriptive and standardized approach that leaves little room for creativity and self-initiative. It pinpoints that supporting volunteers with technical training is critical but that soft skills training such as coordinating, communicating,or facilitating activities at the local level are needed. It concludes that the sustainability of Good and Ready requires understanding and meeting volunteers' motivations and expectations and that enhancing partnerships with local emergency management agencies would strengthen the program.

关键词： community-based approach disaster risk reduction New Zealand Participation Volunteers

Polio eradication surveillance in Sri Lanka,2019-2023

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Asian Pacific Journal of Tropical Medicine 2024年第6期17卷 268-272页

作者： M.A.Y.Fernando N.S.Madarasinghe c.Rangana N.Weerasinghe d.c.U.d.Weligamage J.I.Abeynayake department of Medical Microbiology and Immunology Faculty of MedicineUniversity of ColomboSri Lanka department of Virology Medical Research InstituteColombo 08Sri Lanka Medical Research Institute Colombo 08Sri Lanka

Objective:To evaluate the polio laboratory surveillance carried out from January,2019 to May,2023 by the Polio Regional Reference Laboratory,Sri ***:This retrospective study analyzed all stool samples received under the acute flacc.d.paralysis(AFP)and immunodeficient vaccine-derived poliovirus(VdPV)surveillance at Polio Regional Reference Laboratory,Sri Lanka from January,2019 to May,*** results of the testing methodologies were extracted from the laboratory data system,i.e.,poliovirus virus isolation,intra-typic.d.fferentiation/VdPV real time reverse transcriptase polymerase chain reaction(ITd/VdPV rRTPcR)and sequencing,along with the data on timing of reporting results,stool adequacy and *** was analyzed using descriptive ***:A total of 2141 stool samples from 1644 cases were received for AFP surveillance from Sri Lanka(93.61%),Maldives(1.52%),and immunodeficient VdPV(4.86%)*** polioviruses(19/1644,1.15%)and non-polio enteroviruses(73/1644,4.44%)were isolated,while Sabin-like 3 virus was detected in majority(12/19,63.15%)among the poliovirus *** polioviruses or circulating VdPVs were not detected among the *** all years of the study,the non-polio AFP detection rate was>1/100000 in children aged less than 15 years,whereas stool adequacy rate was>80%.All results were reported within 14 days of receipt,ensuring timely reporting as per global ***:The Polio Regional Reference Laboratory,Sri Lanka plays a vital role in maintaining the polio-free status in the country through its robust laboratory surveillance,while adhering to the surveillance ***-detection of wild polioviruses and circulating VdPV during the study period reinforces the polio-free status in the country.

关键词： Poliovirus Polio laboratory surveillance Regional reference laboratory Polio eradication

Solar-driven cO_(2) conversion to methane and methanol using different nanostructured cu_(2)O-based catalysts modified with Au nanoparticles

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Journal of Energy chemistry 2024年第4期91卷 287-298页

作者： João Angelo Lima Perini Lilian d.Moura Torquato Juliana Fde Brito Gustavo A.Andolpho Mateus A.Gonçalves Leonardo d.de Angelis Lucas d.Germano Susana I.córdoba de Torresi Teodorico c.Ramalho Maria V.Boldrin Zanoni São Paulo State University(UNESP) Institute of ChemistryRua Prof.Francisco Degni55AraraquaraSP 14800-060Brazil National Institute of Alternative Technologies for detection Toxicological Evaluation and Removal of Micropollutants and Radioactive Substances(INCT-DATREM)São Paulo State University(UNESP)Institute of ChemistryRua Prof.Francisco Degni55AraraquaraSP 14800-060Brazil Laboratory of Molecular Modelling Department of ChemistryNatural Sciences InstituteFederal University of LavrasLavrasMG 37200-900Brazil department of chemistry Faculty of ScienceUniversity of Hradec KrálovéHradec Králové50003Czech Republic Instituto de Química Universidade de São PauloAv.Prof.Lineu Prestes 74805508-080São PauloSPBrazil

This work describes the use of TiO_(2)nanotubes-based electrodes(TNT)modified with cu_(2)O nanostructures and gold nanoparticles for the photoelectroreduction of cO_(2)to produce value-added compounds.A thin layer of polydopamine was used as both an adherent agent and an electron transfer mediator,due to itsπ-conjugated electron *** highest production yield was achieved using a TNT@PdA/Nc/Au40%electrode,with Faradaic efficiencies of 47.4%(110.5μM cm^(-2))and 27.8%(50.4μM cm^(-2))for methanol and methane,*** performance of the photoelectrodes was shown to be cu_(2)O facet-dependent,with cubic structures leading to greater conversion of cO_(2)to methanol(43%)and methane(27%),compared to the octahedral morphology,while a higher percentage of metallic gold on the nanostructured cu_(2)O surface was mainly important for *** functional theory(dFT)calculations supported these findings,attributing the superior photoelectrocatalytic performance of the TNT@PdA/Nc/Au40%electrode for cH4generation to the formation of an OcH3intermediate bonded to Au *** using isotope-labeling and analysis by gas chromatograph-mass(Gc-MS)demonstrated that13cO_(2)was the source for photoelectrocatalytic generation of13cH3OH and13cH313cH2OH.

关键词： cu_(2)O nanocubes Photoelectrocatalysis Polydopamine cO_(2) photoelectroreduction dFT calculations

Exploring one material for dual applications:A red-emitting Mg2GeO4:Eu3+ nanophosphor for future generation energy efficient WLEds and dosimetric applications

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Journal of Rare Earths 2024年第10期42卷 1835-1845页

作者： Akshay Arjun G.P.darshan S.c.Sharma H.Nagabhushana d.V.Sunitha H.B.Premkumar department of Physics Faculty of Mathematical and Physical SciencesM.S.Ramaiah University of Applied Sciences Jain University c.N.R.Rao centre for Advanc.d.Materials Tumkur University School of Applied Sciences (Physics) REVA University

The envisaged design and developme nt of individual mate rials to excavate a broader spectrum of desired properties and offer multiple applications are highly *** this in mind,a series of forsterite-structured Mg2GeO4:Eu3+（1 mol%-9 mol%） nanophosphors was synthesized via a solution combustion method using oxalyl dihydrazide as a *** X-ray diffraction patterns confirm the orthorhombic crystal system with a Puma space *** results clearly show irregularly shaped cluster-like structures with aggregation of the *** diffuse reflectance spectra,the optical energy band gap of the Mg2GeO4:Eu3+（1 mol%-9 mol%） nanophosphors was estimated and obtained to be～4.12-4.32 *** photoluminescence emission spectra exhibit intense peaks at ～579,589,610,661,and 707 nm,which are due to characteristic.d.→7F0,5d0→7F1,5do→7F2,5d0→7F3and5d0→7F4transitions of Eu3+ions,*** commission International de L'Eclairage color coordinates are gradually tuned from pale red（0.5980,0.4012） to a pure red（0.6385,0.3611） *** glow peaks showcase excellent super-linear response at low doses of γ-irradiations,indicating that the prepared phosphor can be used in thermoluminescent personal dosimetry which is a biological tissue *** aforementioned results demonstrate that the prepared Mg2GeO4:Eu3+（1 mol%-9 mol%） nanophosphors are considered an excellent candidate for dual applications,i.e.,red component in future generation white-light-emitting diodes（WLEds） and personal dosimetric applications.

关键词： dosimetry Nanophosphors Photoluminescence Photometric properties Rare earths Thermoluminescence

Atomistic Investigation of Shock-Induc.d.Amorphization within Micro-shear Bands in Hexagonal close-Packed Titanium

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1590-1600页

作者： Z.c.Meng K.G.Wang T.Ali d.Li c.G.Bai d.S.Xu S.J.Li A.H.Feng G.J.cao J.H.Yao Q.B.Fan H.Wang R.Yang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Interdisciplinary centre for Additive Manufacturing(IcAM) School of Materials and ChemistryUniversity of Shanghai for Science and TechnologyShanghai 200093China School of Materials Science and Engineering Tongji UniversityShanghai 201804China Key Laboratory for Light-Weight Materials Nanjing Tech UniversityNanjing 210009China National Key Laboratory of Science and Technology on Materials Under Shock and Impact School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology chongqing Innovation center Chongqing 401135China

The mechanical response of a single crystal titanium sample against(0001)α surface impact was investigated using molecular dynamics ***,non-uniform plastic.d.formation was observed in the *** high strain rates,amorphization occurred near the edge of the contact region where severe shear strain induc.d.a large number of stacking faults(SFs)and *** contrast,the central part of the contact region underwent less deformation with significantly fewer ***,instead of amorphization by consuming SFs and dislocations,there was a gradual increase in the density of dislocations and SFs during the process of *** local amorphous regions eventually grew into shear bands.

关键词： Shock compression Amorphization Shear band Titanium Molecular dynamics

Analysis of switching conditions of chalcogenide alloys during crystallization

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Journal of University of Science and Technology Beijing 2006年第5期13卷 446-449页

作者： Wanhua Yu c.d. Wright Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China School of Engineering and computer Science University of Exeter Exeter EX4 4QF UK

To understand the principle and limitation of chalcogenide alloy Ge2Sb2Te5 （GST） in solid-state memory devices during crystallization, it was necessary to develop a physically realistic model that could reflect the electrical and thermal properties of these media. A novel comprehensive numerical model has been developed for simulating these memory devices, which describes the electrical and thermal behavior using the solution of the nonlinear, time-dependent electrical and heat conduction equation. The finite-difference-time-domain technique was adopted to compute the electrical field and heat distribution in the device. Several contributing factors that affect the crystallization switching process such as the geometry of the GST layer, temperature and electric field dependency of the electrical conductivity have been discussed. The results of the simulations were then used to provide critical guidelines for fabrication and optimization of the device performance.

关键词： chalcogenide alloy crystallization simulation modeling memory