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MIcROSTRUcTURE AND TENSILE PROPERTY OF AN AS-cAST DUPLEX STAINLESS STEEL

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Acta Metallurgica Sinica(English Letters) 2001年第4期14卷 285-290页

作者： P.L. Mao1,2), k. Yang1) and c. Y. Su1) 1) Institute of Metal Research, The chinese Academy of Sciences, Shengyang 110016, china 2) School of Metal Material, Shenyang University of Technology, Shengyang 110023, china Institute of Metal Research The Chinese Academy of Sciences School of Metal Material Shenyang University of Technology

The effect of high temperature solution heat treatment on the microstructure and tensile property of as-cast 0cr17Mnl4Mo2N duplex stainless steel was investigated. It was found that the morphology of δ-ferrite in the dual phases microstructures changed gradually from dendritic to lamellar and then to spheroidal, and its distribution became more uniform under appropriate treatment. When the treat temperature was lower than 1250°c, the spheroidal ratio and the homogeneous distribution of δ-ferrite increased with the increase of temperature, which corresponds to a better tensile property. In addition, when the treat temperature reached 1250°c and above, the microstructure consists of coarse equiaxial δ-ferrite grains with the needle austenite at its boundaries, which results in the decrease of the tensile properties of the steel.

关键词： Mechanical properties Metal castings Microstructure Tensile properties

Dynamic Active Noise control of Broadband Noise in Fighter Aircraft Pilot Helmet

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Sound & Vibration 2022年第4期56卷 319-331页

作者： Y.k.Bharath S.Veena Malnad college of Engineering Hassan573202India National Aerospace Laboratories Bengaluru560017India

This paper presents the development of a dynamic Active Noise control(ANc)algorithm aimed towards redu-cingthe broadbandnoiseinside the helmet earcups ofaﬁghter aircraftpilot *** dynamicANc involves a Variable Step-Size Grifﬁths(VSSG)FxLMS algorithm to attenuate noise entering directly through helmet,a LMS based adaptive noise canceller to attenuate noise entering through the pilot microphone,and energy detectors for failure protection and optimized battery power *** algorithms are implemented on Texas Instruments’TMS320c6748 processor and are tested in a helmet ANc experimental setup.

关键词： Active noise control Variable Step-Size Grifﬁths algorithm FxLMS

^(11)c-蛋氨酸PET显像诊断胶质瘤的价值

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中华核医学杂志 2003年第2期23卷 75-76页

作者：邵虹 Trampal c 吴靖川上海第二医科大学附属新华医院儿童医学中心影像诊断中心 200127 瑞典乌普萨拉大学PET中心上海第二医科大学附属新华医院儿童医学中心核医学科 200127

目的　评价1 1 c 蛋氨酸 (MET)PET显像诊断胶质瘤及鉴别良恶性胶质瘤的价值。方法2 2例经病理检查证实的不同分级胶质瘤患者行1 1 c METPET显像 ,对病灶进行定量分析。结果　 2 2例患者的瘤组织均有明显1 1 c MET摄取且与周围正常组织... 详细信息

目的　评价1 1 c 蛋氨酸 (MET)PET显像诊断胶质瘤及鉴别良恶性胶质瘤的价值。方法2 2例经病理检查证实的不同分级胶质瘤患者行1 1 c METPET显像 ,对病灶进行定量分析。结果　 2 2例患者的瘤组织均有明显1 1 c MET摄取且与周围正常组织分界清晰 ,Ⅰ～Ⅱ级胶质瘤热点计数与对侧相同部位 (HS cA)放射性比值为 1 .57± 0 .2 8,明显低于Ⅲ～Ⅳ级胶质瘤 (3 .0 6± 0 .47,t=6 .48,P cA比值差异无显著性 (t=1 .85 ,P >0 .0 5)。结论　1 1 c METPET显像有助于鉴别诊断不同分级的胶质瘤。

关键词： ^11c-蛋氨酸 PET显像诊断胶质瘤碳放射性同位素

kinetics and mechanistic investigation of epoxide/cO2 cycloaddition by a synergistic catalytic effect of pyrrolidinopyridinium iodide and zinc halides

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Journal of Energy chemistry 2019年第10期28卷 35-42页

作者： Abdul Rehman Valentine c. Eze M.F.M.Gunam Resul Adam Harvey School of Engineering Merz CourtNewcastle UniversityNewcastle Upon Tyne NE1 7RUUK Department of chemical and Polymer Engineering University of Engineering and Technology LahoreFaisalabad CampusPakistan

Formation of styrene carbonate (Sc) by the cycloaddition of cO2 to styrene oxide (SO) catalysed by pyrrolidinopyridinium iodide (PPI) in combination with zinc halides (Zncl2, ZnBr2 and ZnI2) was investigated. complete conversion of the SO to Sc was achieved in 3 h with 100% selectivity using 1/0.5 molar (PPI/ZnI2) catalyst ratio under mild reaction conditions i.e., 100℃ and 10 bar cO2 pressure. The synergistic effect of ZnI2 and PPI resulted in more than 7-fold increase in reaction rate than using PPI alone. The cycloaddition reaction demonstrated the first-order dependence with respect to the epoxide, cO2 and catalyst concentrations. Moreover, the kinetic and thermodynamic activation parameters of Sc formation were determined using the Arrhenius and Eyring equations. The positive values of △H(42.8 kJ mol^-1) and △G(102.3 kJ mol^-1) revealed endergonic and chemically controlled nature of the reaction, whereas the large negative values of △S(-159.4 J mol^-1 k^-1) indicate a highly ordered activated complex at the transition state. The activation energy for Sc formation catalyzed by PPI alone was found to be 73.2 kJ mol^-1 over a temperature range of 100-140℃, which was reduced to 46.1 kJ mol^-1 when using PPI in combination with ZnI2 as a binary catalyst. Based on the kinetic study, a synergistic acid-based reaction mechanism was proposed.

关键词： cycloaddition cO2 utilization cyclic carbonates Homogeneous catalysis Activation energy

Laser-induced graphene-coated wearable smart textile electrodes for biopotentials signal monitoring

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Frontiers of Materials Science 2024年第1期18卷 95-111页

作者： c.M.Vidhya Yogita Maithani Sakshi kapoor J.P.Singh Department of Physics Indian Institute of Technology DelhiHauz KhasNew Delhi 110016India

This paper describes how to produce a wearable dry electrode at a reasonable cost and how to use it for the monitoring of biopotentials in *** textiles in wearable technologies have made a great advancement in the health care management and living standards of *** was manufactured using the low-cost single-step process,laser ablation of polyimide,a commercial *** dispersions were made using solvent isopropyl alcohol which has low boiling point,nontoxicity,and environmental *** successive coating of the graphene dispersion on the cotton fabric to make it conductive,the sheet resistance of the resulting fabric dropped to 3% of its initial *** laser-induced graphene(LIG)cotton dry electrodes thus manufactured are comparable to Ag/Agcl wet electrodes in terms of the skin-to-electrode impedance,measuring between 78.0 and 7.2 kΩ for the frequency between 40 Hz and 1 *** LIG cotton electrode displayed a signal-to-noise ratio of 20.17 *** to its comfort,simplicity,and good performance over a longer period of time,the textile electrode appears suited for medical applications.

关键词： biopotential electrocardiogram electromyogram flexible electrode textile porous graphene

cadmium removal mechanistic comparison of three Fe-based nanomaterials: Water-chemistry and roles of Fe dissolution

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Frontiers of Environmental Science & Engineering 2022年第12期16卷 15-29页

作者： Xiaoge Huang Lihao chen Ziqi Ma kenneth c.carroll Xiao Zhao Zailin Huo college of Water Resources and civil Engineering China Agricultural UniversityBeijing100083China Plant&Environmental Science Department New Mexico State UniversityLas CrucesNM88003USA

cadmium(cd)is a common toxic heavy metal in the *** cd(II)as a target contaminant,we systematically compared the performances of three Fe-based nanomaterials(nano zero valent iron,nZVI;sulfidated nZVI,S-nZVI;and nano FeS,nFeS)for cd immobilization under anaerobic *** of nanomaterials doses,initial pH,co-existing ions,and humic acid(HA)were *** identical conditions,at varied doses or initial pH,cd(II)removal by three materials followed the order of S-nZVI>nFeS>*** pH 6,the cd(II)removal within 24 hours for S-nZVI,nFeS,and nZVI(dose of 20 mg/L)were 93.50%,89.12%and 4.10%,*** fast initial reaction rate of nZVI did not lead to a high removal *** cd removal was slightly impacted or even improved with co-existing ions(at 50 mg/L or 200 mg/L)or HA(at 2 mg/L or 20 mg/L).characterization results revealed that nZVI immobilized cd through coprecipitation,surface complexation,and reduction,whereas the mechanisms for sulfidated materials involved replacement,coprecipitation,and surface complexation,with replacement as the predominant reaction.A strong linear correlation between cd(II)removal and Fe(II)dissolution was observed,and we proposed a novel pseudo-second-order kinetic model to simulate Fe(II)dissolution.

关键词： Nano zero valent iron Sulfided zero valent iron FeS cd(II)immobilization Fe dissolution

Laboratory visualization of damage asymmetry formation of rock fracture via acoustic emission and digital imaging correlation

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第11期16卷 4480-4490页

作者： Qiquan Xiong Qing Lin Yue Gao Yanhui Han Jesse c.Hampton Geomechanics and Damage Group(GeoD) Department of Civil and Environmental EngineeringUniversity of Wisconsin-MadisonMadisonWI53706USA State key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China college of Petroleum Engineering China University of PetroleumBeijing102249China Aramco Americas:Aramco Research center-Houston HoustonTX77084USA

Rock fracture mechanics and accurate characterization of rock fracture are crucial for understanding a variety of phenomena interested in geological engineering and *** phenomena range from very large-scale asymmetrical fault structures to the scale of engineering projects and laboratory-scale rock fracture *** study can involve mechanical modeling,site or post-mortem investigations,and inspection on the point cloud of the source locations in the form of earthquake,microseismicity,or acoustic *** study presents a comprehensive data analysis on characterizing the forming of the asymmetrical damage zone around a laboratory mixed-mode rock *** substantiate the presence of asymmetrical damage through qualitative analysis and demonstrate that measurement uncertainties cannot solely explain the observed *** implications of this demonstration can be *** a larger scale,it solidifies a mechanical model used for explaining the contribution of aseismic mechanisms to asymmetrical fault *** a laboratory scale,it exemplifies an alternative approach to understanding the observational difference between the source location and the in situ or post-mortem inspection on the rock fracture *** mechanical model and the data analysis can be informative to the interpretations of other engineering practices as well,but may face different types of challenges.

关键词： Shear fracture Dynamics of fracture Acoustic emission Digital image correlation Uncertainty analysis Error ellipsoid

How are children with medical complexity being identified in epidemiological studies?A systematic review

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World Journal of Pediatrics 2023年第10期19卷 928-938页

作者： Patrícia Vicente Oliveira carla c.Enes Luciana B.Nucci Postgraduate Program in Health Sciences Center for Life SciencesPontifical Catholic University of CampinasAv.John Boyd Dunlop s/nCampinasCEP 13060-904Brazil Postgraduate Program in Health Sciences School of NutritionPontifical Catholic University of CampinasSão PauloBrazil Postgraduate Program in Health Sciences School of MedicinePontifical Catholic University of CampinasSão PauloBrazil

Background There are different definitions to identify/classify children with medical complexity(cMc).We aimed to investigate and describe the definitions used to classify cMc in epidemiological *** PubMed,SciELO,LILAcS,and EMBASE were searched from 2015 to 2020(last updated September 15th,2020)for original studies that presented the definition used to classify/identify cMc in the scientific research *** applied the Preferred Reporting Items for Systematic Reviews and Meta-Analyses *** the included studies,the following were identified:first author,year of publication,design,population,study period,the definition of cMc used,limitations,and *** Nine hundred and sixty-seven records were identified in the searched databases,and 42 met the inclusion *** the 42 studies included,the four most frequent definitions used in the articles included in this review were classification of cMc into nine diagnostic categories based on the International classification of Diseases,Ninth Revision(IcD-9)(35.7%,15 articles);update of the previous classification for IcD-10 codes with the inclusion of other conditions in the definition(21.4%,nine articles);definition based on a medical complexity algorithm for classification(16.7%,seven articles);and a risk rating system(7.1%,three articles).conclusions cMc definitions using diagnostic codes were more ***,several limitations were found in its *** research highlighted the need to improve health information systems to accurately characterize the cMc population and promote the provision of comprehensive care.

关键词： children with medical complexity complex chronic conditions Epidemiologic studies Pediatrics Systematic review

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3期15卷 374-387页

作者： Loïc Le Dé Steve Ronoh Ei Mon Thinn kyu Brigitte Rive School of Public Health and Interdisciplinary Studies Auckland University of TechnologyAuckland2025New Zealand Pacific Health Research centre Auckland University of TechnologyAuckland2025New Zealand New Zealand Red cross Auckland2241New Zealand

Global and national policy frameworks emphasize the importance of people's participation and volunteers'role in disaster risk *** 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 *** 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 *** research examined the positive and negative outcomes of Good and Ready and investigated volunteers'experiences in the disaster resilience *** 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 *** 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 *** 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 *** 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