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Acta Metallurgica Sinica(english Letters) 2024年第2期37卷 255-265页

作者： X.y.yue S.y.Peng X.Zhang c.n.He y.Z.Tian Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China School of Materials Science and engineering and Tianjin Key Laboratory of composite and Functional Materials Tianjin UniversityTianjin300350China Research centre for Metallic Wires Northeastern UniversityShenyang110819China

A cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution *** hot-pressed sintered and solution treated materials were rolled and *** precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron *** contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the cu-10wt%Fe *** cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IAcS and softening temperature of 838 *** for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were *** findings provide a theoretical basis for designing high-performance cu-based in-situ composites by post treatment.

关键词： cu-Fe composite Hot-pressed sintering Thermal stability Strength Electrical conductivity

Optimization of chemistry and process parameters for control of intermetallic formation in Mg sludges

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Journal of Magnesium and Alloys 2024年第4期12卷 1431-1448页

作者： y.Fu G.G.Wang A.hu y.Li K.B.Thacker J.P.Weiler H.hu Department of Mechanical Automotive and Materials EngineeringUniversity of Windsor401 Sunset AveWindsorOntario N9B 3P4Canada Global Technology centre Meridian Lightweight Technologies25 MacNab AveStrathroyOntario N7G 4H6Canada

Intermetallic formation in sludge during magnesium(Mg)melting,holding and high pressure die casting practices is a very important ***,very often it is overlooked by academia,original equipment manufacturers(OEM),metal ingot producers and even die *** aim of this study was to minimize the intermetallic formation in Mg sludge via the optimization of the chemistry and process *** Al8Mn5 intermetallic particles were identified by the microstructure analysis based on the Al and Mn *** design of experiment(DOE)technique,Taguchi method,was employed to minimize the intermetallic formation in the sludge of Mg alloys with various chemical compositions of Al,Mn,Fe,and different process parameters,holding temperature and holding *** sludge yield(Sy)and intermetallic size(IS)was selected as two *** optimum combination of the levels in terms of minimizing the intermetallic formation were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,690℃ for the holding temperature and holding at 30 mins for the holding time,*** best combination for smallest intermetallic size were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,630℃ for the holding temperature and holding at 60 mins for the holding time,*** groups of sludge factors,chemical Sludge(cSF),Physical Sludge(PSF)and comprehensive Sludge Factors(and cPSF)were established for prediction of sludge yields and intermetallic sizes in Al-containing Mg *** cPSF with five independent variables including both chemical elements and process parameters gave high accuracy in prediction,as the prediction of the PSF with only the two processing parameters of the melt holding temperature and time showed a relatively large deviation from the experimental *** chemical Sludge Factor was primarily designed for small ingot producers and die casters with a limited melting and holding capacity,of which process parameters could be fixed *** Physical Sludge Factor could be used f

关键词： Magnesium sludge Al-Mn intermetallic Optimization Taguchi method Sludge factor chemical composition Process parameter

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 flaccid 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 differentiation/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

Inclusion of coTiO_(3) to ameliorate the re/dehydrogenation properties of the Mg–na–Al system

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Journal of Magnesium and Alloys 2024年第3期12卷 1215-1226页

作者： n.A.Ali n.y.yusnizam n.A.Sazelee Sami-ullah Rather Haizhen Liu M.Ismail Energy Storage Research Group Faculty of Ocean Engineering TechnologyUniversiti Malaysia Terengganu21030 Kuala NerusTerengganuMalaysia Department of chemical and Materials engineering King Abdulaziz UniversityP.O.Box80204Jeddah 21589Saudi Arabia Guangxi novel Battery Materials Research center of engineering Technology School of Physical Science and TechnologyGuangxi UniversityNanning 530004China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for composite Structures Nanning 530004China

For the first time,the MgH_(2)–naAlH_(4)(ratio 4:1)destabilized system with coTiO_(3) addition has been *** coTiO_(3)-doped MgH_(2)–naAlH_(4) sample begins to dehydrogenate at 130℃,which is declined by 40℃ compared to the undoped MgH_(2)–naAlH_(4).Moreover,the de/rehydrogenation kinetics characteristics of the coTiO_(3)-doped MgH_(2)–naAlH_(4) were greatly *** the inclusion of coTiO_(3),the MgH_(2)–naAlH_(4) composite absorbed 5.2 wt.%H_(2),higher than undoped MgH_(2)–naAlH_(4).In the context of dehydrogenation,the coTiO_(3)-doped MgH_(2)–naAlH_(4) sample desorbed 2.6 wt.%H_(2),almost doubled compared to the amount of hydrogen desorbed from the undoped MgH_(2)–naAlH_(4) *** activation energy obtained by the Kissinger analysis for MgH_(2) decomposition was significantly lower by 35.9 kJ/mol than the undoped MgH_(2)–naAlH_(4) *** reaction mechanism demonstrated that new phases of Mgco and AlTi_(3) were generated in situ during the heating process and are likely to play a substantial catalytic function and be useful in ameliorating the de/rehydrogenation properties of the destabilized MgH_(2)–naAlH_(4) system with the inclusion of coTiO_(3).

关键词： Destabilize system Magnesium hydride Sodium alanate Hydrogen storage Additive.

Influence of biomass burning on ozone levels in the Megalopolis of central Mexico during the cOVID-19 lockdown

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Journal of Environmental Sciences 2024年第9期143卷 99-115页

作者： Victor Almanza Luis Gerardo Ruiz-Suárez Ricardo Torres-Jardón Agustín García-Reynoso Iván y.Hernández-Paniagua Institute for Atmospheric Sciences and climate change National Autonomous University of MexicoCoyoacan 04510Mexico CityMexico

The massive reductions in anthropogenic emissions resulting from the cOVID-19 lockdown provided a unique opportunity to evaluate the effect of mitigation measures aiming to abate air *** Mexico,the total lockdown period took place during the dry-hot season when biomass burning activity is ***,we investigate the role of biomass burning emissions on regional ozone levels in the Megalopolis of central *** studied period covers the lockdown phases 2 and 3,and the first month of the new *** applied a factor separation technique and process analysis to estimate the pure and synergistic contributions of emission reductions under lockdown and that from biomass burning to daily ozone maximum concentrations in 7 metropolitan areas of different states in the *** results revealed that biomass burning plumes likely masked the effect of massive reductions from mobile emissions,impacted the PBL development during phase 3 and favored transition and mixed nO_(x)-limited and VOc-limited regional *** contributed to increased ozone production in the middle to lower PBL by changing the regional background levels which potentially could bias high ozone production efficiency *** the Megalopolis contribution to economic and societal development at national scale,our study suggests that ozone mitigation measures during the dry-hot season targeting mainly mobile emissions will likely be offset by biomass burning plumes.A regional and synergic policy aiming to control biomass burning would help to reduce the occurrence of high ozone levels in central Mexico with the co-benefit of tackling short-lived climate pollutants.

关键词： cOVID-19 Mexico Megalopolis Ozone Factor Separation Process Analysis

Hierarchical control Strategy for Load Regulation Based on Stackelberg Game Theory considering Randomness

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cSEE Journal of Power and Energy Systems 2024年第3期10卷 929-941页

作者： Tingyu Jiang Ping Ju c.y.chung yuzhong Gong college of Energy and Electrical engineering Hohai UniversityNanjing 211100China Department of Electrical engineering City University of Hong KongHong Kong CF624China Department of Electrical and computer engineering University of SaskatchewanSaskatoonSK S7N 5A9Canada cSEE IEEE

Demand response has been recognized as a valuable functionality of power systems for mitigating power *** paper proposes a hierarchical control strategy among the distribution system operator(DSO),load aggregators(LAs),and thermostatically controlled loads(TcLs);the strategy includes a scheduling layer and an executive layer to provide load *** the scheduling layer,the DSO(leader)offers compensation price(cP)strategies,and the LAs(followers)respond to cP strategies with available regulation power(ARP)*** of the DSO and LAs are modeled according to their behaviors during the load regulation *** game is adopted to capture interactions among the players and leader and to obtain the optimal strategy for each participant to achieve ***,considering inevitable random factors in practice,e.g.,renewable generation and behavior of users,two different stochastic models based on sample average approximation(SAA)and parameter modification are formulated with improved scheduling *** the executive layer,distributed TcLs are triggered based on strategies determined in the scheduling layer.A self-triggering method that does not violate user privacy is presented,where TcLs receive external signals from the LA and independently determine whether to alter their operation *** simulations are performed on the modified IEEE-24 bus system to verify effectiveness of the proposed strategy.

关键词： Demand response hierarchical control load regulation self-triggering method Stackelberg game

Investigation of mechanical and electrical characteristics of selfsensing pneumatic torsional actuators

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Science china(Technological Sciences) 2024年第1期67卷 130-142页

作者： XIAO Wei hu DeAn hu GuoLiang XIAO yihua Key Laboratory of convey.nce and Equipment Ministry of EducationEast China Jiaotong UniversityNanchang 330013China Key Laboratory of Advanced Design and Simulation Techniques for Special Equipment Ministry of EducationHunan UniversityChangsha 410082China

Soft pneumatic actuators are one of the most promising actuation for soft robots,and great achievements have been *** it remains challenging to endow sensing capabilities to pneumatic actuators,especially for the sensing ability originating directly from the actuator ***,a self-sensing pneumatic torsional actuator(SPTA)is designed based on the electromagnetic induction effect and magnetically responsive *** SPTA can generate feedback voltage and current with the deformation,in which the sensing function comes from its inherent *** investigate the mechanical and electrical characteristics,an experimental platform and a finite element model are established,*** find that the torsion angle and output torque increase in nonlinear with the actuating *** maximum torsion angle is 66.35°,which is 84.34%of that for the actuator fabricated by pure *** maximum output torque(24.9 n mm)improves by 23.19%compared with the actuator made by pure *** regards the electrical characteristics,the maximum feedback voltage and current are 2.90μV and 29.50 nA when the SPTA is actuated by a pressure of−40 *** also demonstrate that the relationship between the torsion angle and the magnetic flux change is approximately ***,the number of turns of wires,magnetic powders contents,and magnetic direction on the feedback voltage and current are *** show that the feedback voltage and current can be enhanced by increasing the number of turns and magnetic powders *** envision that the SPTA would be promising for soft robots to realize their accuracy control and intelligentization.

关键词： pneumatic torsional actuators self-sensing feedback voltage finite element modeling soft robots

Effect of Al_(2)O_(3)on the Mechanical Properties of(B_(4)c+Al_(2)O_(3))/Al neutron Absorbing Materials

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Acta Metallurgica Sinica(english Letters) 2024年第8期37卷 1411-1420页

作者： J.X.cai B.M.Shi n.Li y.Liu Z.G.Zhang y.n.Zan Q.Z.Wang B.L.Xiao Z.y.Ma Shi‑changxu Innovation center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory of nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Department of Materials Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

B_(4)c/Al composites are widely utilized as neutron absorbing materials for the storage and transportation of spent nuclear *** order to improve the high-temperature mechanical properties of B_(4)c/Al composites,in-situ nano-Al_(2)O_(3)was introduced utilizing oxide on Al powder *** this study,the Al_(2)O_(3)content was adjusted by utilizing spheroid Al powder with vary.ng diameters,thereby investigating the impact of Al_(2)O_(3)content on the tensile properties of(B_(4)c+Al_(2)O_(3))/Al *** was found that the pinning effect of Al_(2)O_(3)on the grain boundaries could hinder the recovery of dislocations and lead to dislocation accumulation at high *** the result,with the increase in Al_(2)O_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al powder used in this investigation had a diameter of 1.4μm,whereas the resultant composite exhibited a maximum strength of 251 MPa at room temperature and 133 MPa at 350℃,surpassing that of traditional B_(4)c/Al composites.

关键词： Al matrix composites neutron absorbing materials (B_(4)c+Al_(2)O_(3))/Al composites High-temperature strength

Physics-informed deep learning for fringe pattern analysis

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Opto-Electronic Advances 2024年第1期7卷 4-15页

作者： Wei y.n yuxuan che Xinsheng Li Mingyu Li y.n hu Shijie Feng Edmund y.Lam Qian chen chao Zuo Smart computational Imaging Laboratory(ScILab) School of Electronic and Optical EngineeringNanjing University of Science and TechnologyNanjing 210094China Smart computational Imaging Research Institute(ScIRI)of nanjing University of Science and Technology Nanjing 210019China Jiangsu Key Laboratory of Spectral Imaging&Intelligent Sense Nanjing 210094China Department of Electrical and Electronic.engineering The University of Hong KongPokfulamHong Kong SAR 999077China

Recently,deep learning has yielded transformative success across optics and photonics,especially in optical *** neural networks (Dnns) with a fully convolutional architecture (e.g.,U-net and its derivatives) have been widely implemented in an end-to-end manner to accomplish various optical metrology tasks,such as fringe denoising,phase unwrapping,and fringe ***,the task of training a Dnn to accurately identify an image-to-image transform from massive input and output data pairs seems at best naive,as the physical laws governing the image formation or other domain expertise pertaining to the measurement have not yet been fully exploited in current deep learning *** this end,we introduce a physics-informed deep learning method for fringe pattern analysis (PI-FPA) to overcome this limit by integrating a lightweight Dnn with a learning-enhanced Fourier transform profilometry (Le FTP) *** parameterizing conventional phase retrieval methods,the Le FTP module embeds the prior knowledge in the network structure and the loss function to directly provide reliable phase results for new types of samples,while circumventing the requirement of collecting a large amount of high-quality data in supervised learning *** by the initial phase from Le FTP,the phase recovery ability of the lightweight Dnn is enhanced to further improve the phase accuracy at a low computational cost compared with existing end-to-end *** results demonstrate that PI-FPA enables more accurate and computationally efficient single-shot phase retrieval,exhibiting its excellent generalization to various unseen objects during *** proposed PI-FPA presents that challenging issues in optical metrology can be potentially overcome through the synergy of physics-priors-based traditional tools and data-driven learning approaches,opening new avenues to achieve fast and accurate single-shot 3D imaging.

关键词： optical metrology deep learning physics-informed neural networks fringe analysis phase retrieval

Early Phases of Star Formation: Testing chemical Tools

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Research in Astronomy and Astrophysics 2024年第1期24卷 96-118页

作者： n.c.Martinez S.Paron cOnIcET-Universidad de Buenos Aires.Instituto de Astronomía y Física del Espacio Ciudad Universitaria(C1428EGA)Ciudad Autónoma de Buenos AiresArgentina

Star-forming processes strongly influence the ISM ***,many high-quality databases are available at millimeter *** them,it is possible to carry out studies that review and deepen previous *** these studies involve large samples of sources,it is preferred to use direct tools to study the molecular *** the aim of testing these tools such as the use of the Hcn/Hnc ratio as a thermometer,and the use of H^(13)cO^(+),Hc_(3)n,n_(2)H^(+) and c_(2)H as "chemical clocks," we present a molecular line study toward 55 sources representing massive young stellar objects at different evolutionary stages:infrared dark clouds(IRDcs),highmass protostellar objects(HMPOs),hot molecular cores(HMcs) and ultracompact H II *** found that the use of the Hcn/Hnc ratio as a universal thermometer in the ISM should be taken with care because the Hcn optical depth is a big issue that can affect the ***,this tool should be utilized only after a careful analysis of the Hcn spectrum,checking that no line,neither the main nor the hyperfine ones,presents absorption *** point out that the analysis of the emission of H^(13)cO^(+),Hc_(3)n,n_(2)H^(+) and c_(2)H could be useful to trace and distinguish regions among IRDcs,HMPOs and *** molecular line widths of these four species increase from the IRDc to the HMc stage,which can be a consequence of the gas dynamics related to the starforming processes taking place in the molecular *** results not only contribute with more statistics,acting as a probe of such chemical tools,useful to obtain information in large samples of sources,but also complement previous works through the analysis of other types of sources.

关键词： stars:formation ISM:molecules ISM:clouds