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Journal of Magnesium and Alloys 2024年第5期12卷 1931-1943页

作者： Farid Bahari-Sambran Fernando carreno c.M.cepeda-Jiménez Alberto Orozco-caballero Physical Metallurgy Department CENIM-CSICAv.Gregorio del Amo 828040 MadridSpain Department of Mechanical Engineering Chemistry and Industrial DesignPolytechnic University of MadridRonda de Valencia 328012MadridSpain

The aim of this work is to predict,for the first time,the high temperature flow stress dependency with the grain size and the underlaid deformation mechanism using two machine learning models,random forest(RF)and artificial neural network(ANN).With that purpose,a ZK30 magnesium alloy was friction stir processed(FSP)using three different severe conditions to obtain fine grain microstructures(with average grain sizes between 2 and 3μm)prone to extensive superplastic *** three friction stir processed samples clearly deformed by grain boundary sliding(gBS)deformation mechanism at high *** maximum elongations to failure,well over 400% at high strain rate of 10^(-2)s^(-1),were reached at 400℃ in the material with coarsest grain size of 2.8μm,and at 300℃ for the finest grain size of 2μ***,the superplastic response decreased at 350℃ and 400℃ due to thermal instabilities and grain coarsening,which makes it difficult to assess the operative deformation mechanism at such *** work highlights that the machine learning models considered,especially the ANN model with higher accuracy in predicting flow stress values,allow determining adequately the superplastic creep behavior including other possible grain size scenarios.

关键词： Machine learning Artificial intelligence Magnesium alloys Superplasticity Friction stir processing grain coarsening

ground-based and additional science support for SMILE

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Earth and Planetary Physics 2024年第1期8卷 275-298页

作者： J.A.carter M.Dunlop c.Forsyth K.Oksavik E.Donovon A.Kavanagh S.E.Milan T.Sergienko R.c.Fear D.g.Sibeck M.connors T.Yeoman X.Tan M.g.g.T.Taylor K.McWilliams J.gjerloev R.Barnes D.D.Billet g.c.isham A.Dimmock M.P.Freeman D.-S.Han M.D.Hartinger S.-Y.W.Hsieh Z.-J.Hu M.K.James L.Juusola K.Kauristie E.A.Kronberg M.Lester J.Manuel J.Matzka I.Mccrea Y.Miyoshi J.Rae L.Ren F.Sigernes E.Spanswick K.Sterne A.Steuwer T.Sun M.-T.Walach B.Walsh c.Wang J.Weygand J.Wild J.Yan J.Zhang Q.-H.Zhang Planetary Sciences group School of Physics and AstronomyUniversity of LeicesterUniversity RoadLeicesterLE17RHUK Rutherford Appleton Laboratory Space Science Technology Facilities CouncilOxfordshireUK School of Space and Environment Beihang UniversityBeijing 100191China Key Laboratory of Space Environment Monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing 100017China Department of Space and climate Physics UCLMullard Space Science LaboratoryHolmbury St.MaryDorkingSurreyRH56NTUK Birkeland centre for Space Science Department of Physics and Technology.University of BergenBergenNorway Department of Physics and Astronomy University of Calgary2500 University DriveCalgaryAlbertaCanada T2N 1N4 British Antarctic Survey CambridgeUK Swedish Institute of Space Physics KirunaSweden West Highfield campus University of SouthamptonUniversity RoadSO171BJUK goddard Space Flight center NASAGreenbeltMarylandUSA Athabasca University AthabascaCanada ESTEc European Space AgencyNetherlands University of Saskatchewan SaskatoonCanada The Johns Hopkins University Applied Physics Laboratory LaurelMarylandUSA Swedish Institude of Space Physics UppsalaSE 75121Sweden Tongji University Shanghai 200092China center for Space Plasma Physics Space Science Institute4765 Walnut Street Suite BBoulderColorado80301USA Polar Research Institute of china Shanghai 200136China Finnish Meteorolog.c.l Institute(FMI) Finland Department of Earth and Environmental Sciences(geophysics) Ludwig Maximilian University of Munich(LMU)MunichTheresienstr.41MunichD-80333Germany canadian Space Agency MontrealCanada gFZ german Research centre for geosciences PotsdamGermany Nagoya University Institute for Space Earth Environment ResearchCenter for Integrated Data ScienceNagoyaAichiJP 464-8601 Northumbria University Newcastle upon TyneTyne and WearUK NE18ST National Space Science center Chinese Academy SciencesBeijing 100190China Arctic geophysics University Centre in Svalbard

The joint European Space Agency and chinese Academy of Sciences Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will explore global dynamics of the magnetosphere under varying solar wind and interplanetary magnetic field conditions,and simultaneously monitor the auroral response of the Northern Hemisphere *** these large-scale responses with medium and fine-scale measurements at a variety of cadences by additional ground-based and space-based instruments will enable a much greater scientific impact beyond the original goals of the SMILE ***,we describe current community efforts to prepare for SMILE,and the benefits and context various experiments that have explicitly expressed support for SMILE can offer.A dedicated group of international scientists representing many different experiment types and geographical locations,the ground-based and Additional Science Working group,is facilitating these *** include constructing an online SMILE Data Fusion Facility,the discussion of particular or special modes for experiments such as coherent and incoherent scatter radar,and the consideration of particular observing strategies and spacecraft *** anticipate growing interest and community engagement with the SMILE mission,and we welcome novel ideas and insights from the solar-terrestrial community.

关键词： magnetosphere ionosphere magnetosphere-ionosphere coupling ground-based experimentation SMILE conjunctions missions

FINITE ELEMENT gALERKIN APPROAcH FOR A cOMPUTATIONAL STUDY OF ARTERIAL FLOW

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Applied Mathematics and Mechanics(English Edition) 2001年第9期22卷 1012-1018页

作者： g.c.夏玛马德胡.珍阿尼尔.克乌玛 School of Mathematical Sciences Institute of Basic Science Khandari India

A finite element solution for the Navier_Stokes equations for steady flow through a double branched two dimensional section of three dimensional model of canine aorta is obtained. The numerical technique involves transformation of the physical coordinates to a curvilinear boundary fitted coordinate system. The shear stress at the wall is calculated for Reynolds number of 1000 with branch to main aortic flow rate ratio as a parameter. The results are compared with earlier works involving experimental data and it is observed that the results are very close to their solutions. This work in fact is an improvement of the work of Sharma and Kapoor (1995) in the sense that computations scheme is economic and Reynolds number is large.

关键词： shear stress blood flow arterial flow galerkin approach

Outcomes of liver resection in hepatitis c virus-related intrahepatic cholangiocarcinoma:A systematic review and meta-analysis

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World Journal of Virology 2024年第1期13卷 107-119页

作者： Feng Yi cheo Kai Siang.c.an Vishal g Shelat Yong Loo Lin School of Medicine National University of SingaporeSingapore 117597Singapore Department of general Surgery Tan Tock Seng HospitalSingapore 308433Singapore

BAcKgROUND cholangiocarcinoma is the second most common primary liver *** incidence and mortality rates have been increasing in recent *** c virus(HcV)infection is a risk factor for development of cirrhosis and ***,surg.c.l resection remains the only curative treatment option for *** aim to study the impact of HcV infection on outcomes of liver resection(LR)in intrahepatic cholangiocarcinoma(Icc).AIM To study the outcomes of curative resection of Icc in patients with HcV(i.e.,HcV+)compared to patients without HcV(i.e.,HcV-).METHODS We conducted a systematic review and meta-analysis of randomized controlled trials(RcTs)and observational studies to assess the outcomes of LR in Icc in HcV+patients compared to HcV-patients in tertiary care ***,EMBASE,The cochrane Library and Scopus were systematically searched from inception till August *** studies were RcTs and non-RcTs on patients≥18 years old with a diagnosis of Icc who underwent LR,and compared outcomes between patients with HcV+vs HcV-.The primary outcomes were overall survival(OS)and recurrence-free *** outcomes include perioperative mortality,operation duration,blood loss,intrahepatic and extrahepatic *** Seven articles,published between 2004 and 2021,fulfilled the selection *** of the studies were retrospective ***,incidence of male patients,albumin,bilirubin,platelets,tumor size,incidence of multiple tumors,vascular invasion,bile duct invasion,lymph node metastases,and stage 4 disease were comparable between HcV+and *** transaminase[MD 22.20,95%confidence interval(cI):13.75,30.65,PcI:20.20,34.34,Pgnificantly higher in HcV+group compared to *** of cirrhosis was significantly higher in HcV+group[odds ratio(OR)5.78,95%cI:1.38,24.14,P=0.02]compared to *** of poorly

关键词： cholangiocarcinoma Bile duct cancer Hepatitis c Surg.c.l resection Hepatectomy

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.c.mmunitybased 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 codesign 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

A survey of geothermal power generation combined with renewable energy for low carbon emissions

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cLEAN ENERgY 2024年第3期8卷 138-146页

作者： Liu, Xuyang.c.i, Dongsheng Ukwuoma, chiagoziem c. Huang, Qi Bamisile, Olusola chengdu Univ Technol Coll Nucl Technol & Automat Engn Chengdu Sichuan Peoples R China Southwest Univ Sci & Technol Elect Engn Dept Maiyang Sichuan Peoples R China

At present, industrial development is heavily dependent on traditional fossil energy, which has had an increasingly serious impact on the environment. clean and renewable energy has received extensive attention and its proportion in daily life has gradually increased. As a clean and renewable energy source that is not affected by changes in weather and seasons, geothermal energy has developed rapidly in recent years and has received increasing attention. According to reports, the total installed capacity of geothermal power generation in the world in 2020 was 15 950 MW-an increase of similar to 27% over 2015. At the end of 2019, the total installed capacity for global geothermal direct use was 107 727 MW-an increase of 52.0% compared with 2015; the total annual energy use was 1 020 887 TJ (283 580 gWh)-an increase of 72.3% over 2015. Through the investigation of geothermal power generation technology in recent years, the characteristics and shortcomings of various power generation methods are analysed. At the same time, this review analyzes the characteristics of geothermal energy and other renewable-energy (solar energy, water energy) coupling power generation, and analyzes the principles and characteristics of geothermal energy and various new-energy coupling power generation methods. Through investigation and analysis, this review provides a complete understanding of various geothermal power generation technologies and provides insights into the future development direction. [gRAPHIcS] .

关键词： geothermal power generation solar energy water energy combined power generation ABANDONED OIL cOMBINED SYSTEM gAS-WELLS HEAT RESOURcES DRIVEN

Investigations of nuclear chirality at iThemba LABS

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Frontiers of physics 2024年第2期19卷 7-38页

作者： R.A.Bark E.A.Lawrie c.Liu S.Y.Wang iThemba Laboratory for Accelerator Based Sciences National Research FoundationP.O.Box 722Somerset-West 7129South Africa Department of Physics University of the Western CapePrivate Bag X177535BellvilleSouth Africa Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China

Progress in the studies of chirality in atomic nuclei at iThemba LABS is *** regions of chirality,around mass 80 and 190 have been discovered using the AFRODITE array,specifically in the nuclei^(74)As,^(78,80,82)Br,^(81)Kr,and^(193,194,198)*** phenomena have been observed,including multiple chiral bands in the same nucleus,the coexistence of octupole correlations and nuclear chirality,and the coexistence of pseudo spin and nuclear *** best example of chiral degeneracy to date was found in ^(194)*** level scheme of ^(106)Ag has been revisited and interpreted in terms of two-and four-quasiparticle *** using the particle-rotor model have shown that the fingerprints of chirality in the two-quasiparticle system only can occur in an idealised model *** systems with a higher number of quasiparticles,the calculations showed that nuclear chirality can persist.

关键词： chirality high-spin states particle-rotor model

Effects of dust controls on respirable coal mine dust composition and particle sizes:case studies on auxiliary scrubbers and canopy air curtain

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International Journal of coal Science & Technology 2024年第3期11卷 86-101页

作者： F.Animah c.Keles W.R.Reed E.Sarver Department of Mining and Minerals Engineering Virginia Polytechnic Institute&State UniversityBlacksburgVAUSA National Institute of Occupational Safety and Health(NIOSH) PittsburghPAUSA

control of dust in underground coal mines is critical for mitigating both safety and health *** decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the effectiveness of various dust control technologies in coal *** studies have included the evaluation of auxiliary scrubbers to reduce respirable dust downstream of active mining and the use of canopy air curtains(cAcs)to reduce respirable dust in key operator *** detailed dust characterization was not a focus of such studies,this is a growing area of *** preserved filter samples from three previous NIOSH studies,the current work aims to explore the effect of two different scrubbers(one wet and one dry)and a roof bolter cAc on respirable dust composition and particle size *** this,the preserved filter samples were analyzed by thermogravimetric analysis and/or scanning electron microscopy with energy dispersive *** indicate that dust composition was not appreciably affected by either scrubber or the ***,the wet scrubber and cAc appeared to decrease the overall particle size *** an effect of the dry scrubber was not consistently observed,but this is probably related to the particular sampling location downstream of the scrubber which allowed for significant mixing of the scrubber exhaust and other return *** from the insights gained with respect to the three specific dust control case studies revisited here,this work demonstrates the value of preserved dust samples for follow-up investigation more broadly.

关键词： Respirable dust Dust control SEM–EDX Scrubber canopy air curtain Silica

n-Alkane bound biomarker fingerprints from asphaltenes in the bitumens of Eastern Dahomey Basin,Nigeria:Source and genetic implications

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Petroleum Research 2024年第1期9卷 85-91页

作者： Modupe A.Egbeola Olubunmi c.Adeigbe Olajide J.Adamolekun Department of geology University of IbadanIbadanNigeria Structural geology and Tectonics Institute of Applied GeosciencesKIT-Karlsruhe Institute of TechnologyAdenauerring 20a76131KarlsruheGermany

The asphaltene fractions of the bitumens of Eastern Dahomey Basin in Nigeria,were analyzed by flash pyrolysis-gas chromatography(Py-gc)method in order to unravel its geochemical history and *** distributions of the initial biomarkers of the original oils from the pyrolysates are related to the assessment of organic matter source,paleo-redox conditions and source environment during ***,it effectively establishes the genetic relationship of the *** n-alkane distributions in the pyrolysates reveal nc_(9)-nc_(32)n-alkanes,maximizing at nc_(14),isoprenoids-pristane(Pr)and phytane(Ph),and some n-alkene *** peaks of low to medium-weight nc_(9)-nc20 n-alkanes and low peaks of nc_(21)+n-alkanes characterize the *** reveal that abundant algal organic matter with some terrigenous inputs contributed to the source rock of the *** high concentration of marine organic matter inputs to the source rock is further confirmed by the nc_(17)/nc27 ratios which range from 5.39 to 19.82 and shows the predominance of nc_(17)*** general unimodal n-alkane distributions in the bitumens indicate derivation from similar organic matter types showing that they are genetically *** anoxic to suboxic environmental conditions that prevailed during the deposition of the sediments is revealed by the isoprenoids,Pr/Ph ratios(0.72-1.28).Pristane/nc_(17)and Phytane/nc_(18)range from 0.16 to 0.33 and 0.22 to 0.56,revealing that the bitumens were from predominantly marine organic matter(type II kerogen)preserved in a reducing environment with no evidence of ***,the Ph/nc_(18)ratio and the cross plot of Pr+Ph/nc_(17)+nc_(18)allow the classification of the bitumens into two subfamilies/groups(A and B).The bitumen samples have low wax content as indicated by the degree of waxiness ranging from 0.21 to 0.38 which confirms low terrigenous *** on the carbon preference index(cPI:0.92 to 1.55)and odd-even predo

关键词： genetic relationship Flash pyrolysis Biomarker Asphaltene Pyrolysates

Barosinusitis due to routine weather changes:A cross-sectional analysis of public websites

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 18-23页

作者： James c.campbell Julia E.canick Philip g.c.en Ralph Abi Hachem David W.Jang Department of Head and Neck Surgery&communication Sciences Duke University School of MedicineDurhamNorth CarolinaUSA Duke University School of Medicine DurhamNorth CarolinaUSA Department of Otolaryngology-Head and Neck Surgery University of Texas Health Science Center San AntonioSan AntonioTexasUSA

Background:Sinusitis is a common diagnosis that can be erroneously associated with routine weather‐related barometric pressure *** actuality,these pressure changes likely exacerbate migraine headaches,which can cause facial pain and pressure rather than true sinus ***:The present study sought to characterize the representation of both sinusitis and migraine in association with barometric pressure changes across websites on the ***:An Internet search for relevant terms was conducted,and content of the resulting pages was assessed for associations between weather‐related pressure changes and either sinusitis or *** in reported results across different subtypes of Internet sources were *** primary outcomes measured were(1)whether a given media source associated barometric weather changes with sinusitis,(2)whether that source associated barometric weather changes with migraine,and(3)treatment options offered by that ***:Of the 116 included webpages,36(31.03%)associated sinusitis and routine barometric pressure *** these,10(27.77%)were otolaryngology practice ***‐seven webpages(57.76%)associated migraine and routine barometric pressure *** these,nonotolaryngology webpages were more likely to report this ***:Otolaryngology practice sites were observed to be the most frequent professional medical resource reporting the unsubstantiated claim that routine barometric pressure changes are associated with *** sources were more likely to link weather‐related pressure changes to *** results suggest that opportunities exist for otolaryngology practice sites to educate patients about nonrhinogenic headache etiologies.

关键词： acute rhinosinusitis balloon sinus dilation headache migraine sinusitis