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A simple route for prepara.ion of TRIP-assisted Si-Mn steel with excellent performance using direct strip casting

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International Journal of Minera.s,Metallurgy and Materials 2024年第10期31卷 2173-2181页

作者： hui Xu Lejun Zhou Wanlin Wang Yang Yi School of Metallurgy and Environment Central South UniversityChangsha 410083China National Center for International Research of Clean Metallurgy Central South UniversityChangsha 410083China

The complex producing procedures and high energy-consuming limit the la.ge-scale production and application of advanced high-strength steels(AHSSs).In this study,the direct strip casting(DSC)technology with unique sub-ra.id solidification chara.teristics and cost advantages was applied to the production of low-alloy Si-Mn steel with the help of quenching&partitioning(Q&P)concept to address these *** this method with the conventional compact strip production(CSP)process,the initial microstructure formed under different solidification conditions and the influence of heat treatment processes on the final mechanical properties were *** results show that the initial structure of the DSC sample is a dual-phase structure composed of fine la.h martensite and bainite,while the initial structure of the CSP sample consists of pearlite and *** volume fra.tion and carbon content of retained austenite(ra.in DSC samples are usually higher than those in CSP samples after the same Q&P *** samples typically demonstra.e better comprehensive mechanical properties than the CSP *** DSC sample partitioned at 300℃ for 300 s(DSC-Pt300)achieves the best comprehensive mechanical properties,with yield strength(YS)of 1282 MPa,ultimate tensile strength(UTS)of 1501 MPa,total elongation(TE)of 21.5%,and product of strength and elongation(PSE)as high as 32.3 GPa·%.These results indicate that the excellent mechanical properties in low-alloy Si-Mn steel can be obtained through a simple process(DSC-Q&P),which also demonstra.es the superiority of DSC technology in manufacturing AHSSs.

关键词： direct strip casting sub-ra.id solidification quenching and partitioning TRIP-assisted AHSSs microstructure

Particle Size Optimization of Thermochemical Salt Hydra.es for High Energy Density Thermal Stora.e

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Energy & Environmental Materials 2024年第2期7卷 326-333页

作者： Andrew Martin Drew Lilley ra.i Pra.her Sumanjeet Kaur Energy Technologies Area Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA Department of Mechanical Engineering UC BerkeleyBerkeleyCA 94720USA

Thermal energy stora.e(TES)solutions offer opportunities to reduce energy consumption,greenhouse gas emissions,and ***,they can help reduce the peak load and address the intermittency of renewable energy sources by time shifting the load,which are critical toward zero energy *** materials(TCMs)as a cla.s of TES undergo a solid-gas reversible chemical reaction with water vapor to store and release energy with high stora.e capacities(600 kWh m^(-3))and negligible self-discharge that makes them uniquely suited as compact,stand-alone units for daily or seasonal ***,TCMs suffer from instabilities at the material(salt particles)and reactor level(packed beds of salt),resulting in poor multi-cycle efficiency and high-levelized cost of *** this study,a model is developed to predict the pulverization limit or Rcrit of various salt hydra.es during thermal *** is critical as it provides design rules to make mechanically stable TCM composites as well as enables the use of more energy-efficient manufacturing process(solid-state mixing)to make the *** model is experimentally validated on multiple TCM salt hydra.es with different water content,and effect of Rcrit on hydra.ion and dehydra.ion kinetics is also investigated.

关键词： high energy density hydra.ion kinetics long-term cycling thermal energy stora.e thermochemical materials

Phase field modeling of gra.n stability of nanocrystalline alloys by explicitly incorpora.ing mismatch stra.n

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ra.e Metals 2024年第7期43卷 3370-3382页

作者： Min Zhou Hong-hui Wu Yuan Wu hui Wang Xiong-Jun Liu Sui-He Jiang Xiao-Bin Zhang Zhao-Ping Lu Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083Cnina Institute for Carbon Neutra.ity University of Science and TechnologyBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

Ab st ra.ct Nanocrystalline materials exhibit unique properties due to their extremely high gra.n boundary(GB) ***,this high-density chara.teristic induces gra.n coarsening at elevated tempera.ures,thereby limiting the widespread application of nanocrystalline *** experimental observations revealed that GB segregation and second-phase pinning effectively hinder GB migra.ion,thereby improving the stability of nanocry stalline *** this study,a mouified phase-field model that integra.es mismatch stra.n,solute segregation and precipitation was developed to evaluate the influence of la.tice misfit on the thermal stability of nanocrystalline *** simula.ion results indicated that introducing a suitable mismatch stra.n can effectively enhance the microstructura. stability of nanocrystalline *** synergizing precipitation with an appropriate la.tice misfit,the formation of second-phase particles in the bulk gra.ns can be suppressed,thereby facilitating solute segregation/precipitation at the *** concentra.ed solute segregation and precipitation at the GBs effectively hinders gra.n migra.ion,thereby preventing gra.n *** findings provide a new perspective on the design and regula.ion of nanocrystalline alloys with enhanced thermal stability.

关键词： Phase field model Mismatch stra.n Second-phase precipitation Gra.n boundary segregation Nanocrystalline alloys

Combining systemic infla.matory response index and albumin fibrinogen ra.io to predict early serious complications and prognosis after resectable gastric cancer

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 732-749页

作者： Jing-Yao Ren Da Wang Li-hui Zhu Shuo Liu Miao Yu hui Cai School of Clinical Medicine Ningxia Medical UniversityYinchuan 750000Ningxia Hui Autonomous RegionChina Genera. Surgery Clinical Medical Center Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina Key la.ora.ory of Molecula. Diagnostics and Precision Medicine for Surgical Oncology in Gansu Province Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina NHC Key la.ora.ory of Diagnosis and Thera.y of Gastrointestinal Tumor Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina Medical College of Jiangsu University Jiangsu UniversityZhenjiang 212013Jiangsu ProvinceChina The First Clinical Medical School Lanzhou UniversityLanzhou 730000Gansu ProvinceChina

BACKGROUND Gastric cancer has a high incidence and fatality ra.e,and surgery is the preferred course of ***,patient survival ra.es are still low,and the incidence of major postopera.ive complications cannot be *** systemic infla.matory response,nutritional level,and coagula.ion status are key factors affecting the postopera.ive recovery and prognosis of gastric cancer *** systemic infla.matory response index(SIRI)and the albumin fibrinogen ra.io(AFR)are two valuable comprehensive indicators of the severity and prognosis of systemic infla.mation in various medical *** To assess the clinical importance and prognostic significance of the SIRI scores and the AFR on early postopera.ive outcomes in patients undergoing ra.ical gastric cancer *** We conducted a retrospective analysis of the clinicopathological chara.teristics and relevant la.ora.ory indices of 568 gastric cancer patients from January 2018 to December *** calcula.ed and compared two indicators of infla.mation and then examined the diagnostic ability of combined SIRI and AFR values for serious early postopera.ive *** scored the patients and categorized them into three groups based on their SIRI and AFR *** analysis was used to compare the three groups of patients the prognostic value of various preopera.ive SIRI-AFR scores for 5-year overa.l survival(OS)and disease-free survival(DFS).RESULTS SIRI-AFR scores were an independent risk factor for prognosis[OS:P=0.004;hazards ra.io(HR)=3.134;DFS:Pra.ive tra.sfusion(P=0.044),positive carcinoembryonic antigen(P=0.014)findings,and major postopera.ive complications(P=0.011)were factors associated with *** Preopera.ive SIRI and AFR values were s

关键词： Infla.mation Albumin fibrinogen ra.io Gastric cancer Complications Prognosis

Prevalence of visual impairment and estimation of refra.tive errors among school children in Kakamega,Kenya

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 932-939页

作者： Isabel Signes-Soler Alfred ra.ot Sheila. Nangena Andrew Wekesa ra.l Montalbán Lla.usí Department of Optics and Optometry and Vision Sciences Universidat de ValènciaBurjassotValencia 46010Spain NGO Vision Without Borders(Visio Sense Fronteres VSF)Calpe 03710AlicanteSpain Masinde Muliro University of Science and Technology P.O Box 190-50100KakamegaKenya Clinica Baviera.Alicante C/Ausóy Monzó 16Alicante 03006Spain

AIM:To investigate the prevalence of visual impairment(VI)and provide an estimation of uncorrected refra.tive errors in school-aged children,conducted by optometry students as a community ***:The study was *** 3343 participants were included in the *** initial examination involved assessing the uncorrected distance visual acuity(UDVA)and visual acuity(VA)while using a+2.00 D *** inclusion criteria for a subsequent comprehensive cycloplegic eye examination,performed by an optometrist,were as follows:a UDVAra.ge 4 to 17y),and 51.3%of the children were female(n=1715).The majority of the children(89.7%)fell within the age ra.ge of 8 to *** the ethnic groups,the highest representation was from the Luhya group(60.6%)followed by Luo(20.4%).Mean logMAR UDVA choosing the best eye for each student was 0.29±0.17(ra.ge 1.70 to 0.22).Out of the total,246 participants(7.4%)had a full eye *** estimated prevalence of myopia(defined as spherical equivalent≤-0.5 D)was found to be 1.45%of the total *** around 0.18%of the total sample had hyperopia value exceeding+1.75 *** astigmatism(cilra.tive *** was detected in 0.66%(22/3343)of the screened *** was no statistically significant correla.ion observed between age or gender and refra.tive ***:The primary cause of VI is determined to be uncorrected refra.tive errors,with myopia being the most prevalent refra.tive error *** findings underscore the significance of early identification and correction of refra.tive errors in school-aged children as a means to alleviate the impact of VI.

关键词： visual impairment refra.tive errors myopia amblyopia sustainable development goals

Remarkable Wear Resistance in a Complex Concentra.ed Alloy with Nanohiera.chical Architecture and Composition Undula.ion

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Research 2024年第1期2023卷 403-416页

作者： Yushan Geng Wenyuan Chen hui Tan Jun Cheng Shengyu Zhu Jun Yang Weimin Liu State Key la.ora.ory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000PR China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049PR China Shandong la.ora.ory of Yantai Advanced Materials and Green Manufacturing Yantai 264000PR China

Sustained wear damages on the sliding surfaces of alloys are genera.ly the culprit responsible for the failure of various mechanical *** by high-entropy effects,here we delibera.ely deploy nanohiera.chical architecture with composition undula.ion in a Ni50(AlNbTiV)_(50) complex concentra.ed alloy,which yields ultra.ow wear ra.e within the order of 10^(−7) to 10^(−6) mm^(3)/Nm between room tempera.ure and 800℃.Such remarkable wear resistance heretofore represents one of the highest wear resistance reported for the bulk alloys or composites,and originates from the multi-type adaptive friction interface protection governed by intrinsically nano-coupled gra.ns and *** coopera.ive heterostructure releases gra.ient frictional stress in stages upon wear at room tempera.ure through the coexistence of multiple deformation pathways while activating a dense nanocrystalline gla.e la.er upon wear at 800℃ to minimize adhesive and oxidative *** work uncovers a pra.tical avenue for tailoring wear properties with multicomponent heterostructures over a wide tempera.ure ra.ge.

关键词： wear alloys friction

Four buildings and a flush:Lessons from degra.ed water quality and recommendations on building water management

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Environmental Science and Ecotechnology 2024年第2期18卷 104-113页

作者： Kyungyeon ra.Caitlin Proctor Christian Ley Danielle Angert Yoora. Noh Tolulope Odimayomi Andrew J.Whelton Lyles School of Civil Engineering Purdue University550 Stadium Mall DriveWest LafayetteIN47907USA Agricultura. and Biological Engineering Division of Environmental and Ecological EngineeringPurdue UniversityWest LafayetteIN47907USA Division of Environmental and Ecological Engineering Purdue UniversityWest LafayetteIN47907USA Civil and Environmental Engineering University of Colorado1111 Engineering DriveBoulderCO80309USA Civil Architectural and Environmental EngineeringUniversity of Texas301E E Dean Keeton StreetAustinTX78712USA Civil and Environmental Engineering Virginia Tech750 Drillfield DriveBlacksburgVA24061USA Lyles School of Civil Engineering Division of Environmental and Ecological EngineeringPurdue University550 Stadium Mall DriveWest LafayetteIN47907USA

A reduction in building occupancy can lead to stagnant water in plumbing,and the potential consequences for water quality have gained increasing *** investigate this,a study was conducted during the COVID-19 pandemic,focusing on water quality in four institutional *** of these buildings were old(>58 years)and la.ge(>19,000 m2),while the other two were new(>13 years)and small(la.ge *** analysis found that residual chlorine was ra.ely detectable in cold/drinking water ***,the pH,dissolved oxygen,total organic carbon,and total cell count levels in the first dra. of cold water samples were simila. across all ***,the ra.ges of heavy metal concentra.ions in la.ge buildings were greater than observed in small ***(Cu),lead(Pb),and manganese(Mn)spora.ically exceeded drinking water limits at cold water fixtures,with maximum concentra.ions of 2.7 mg Cu L^(-1),45.4 mg Pb L^(-1),1.9 mg Mn L^(-1).Flushing the plumbing for 5 min resulted in detectable residual at fixtures in three buildings,but even after 125 min of flushing in la.gest and oldest building,no residual chlorine was detected at the fixture closest to the building's point of *** the pandemic,the building owner conducted fixture flushing,where one to a few fixtures were opera.ed per visit in buildings with hundreds of fixtures and multiple ***,further research is needed to understand the fundamental processes that control faucet water quality from the service line to the *** the absence of this knowledge,building owners should create and use as-built dra.ings to develop flushing pla.s and conduct periodic water testing.

关键词： COVID-19 pandemic Stagnation Drinking water quality Flushing

Enhancing personalized exercise recommendation with student and exercise portra.ts

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Journal of Electronic Science and Technology 2024年第2期22卷 91-109页

作者： Wei-Wei Gao hui-Fang Ma Yan Zhao Jing Wang Quan-Hong Tian College of Computer Science and Engineering Northwest Normal UniversityLanzhou730070China Computer Center of Gansu Province Lanzhou730070China

The exercise recommendation system is emerging as a promising application in online learning scenarios,providing personalized recommendations to assist students with explicit learning *** solutions genera.ly follow a colla.ora.ive filtering para.igm,while the implicit connections between students(exercises)have been la.gely *** this study,we aim to propose an exercise recommendation para.igm that can reveal the la.ent connections between student-student(exercise-exercise).Specifically,a new fra.ework was proposed,namely personalized exercise recommendation with student and exercise portra.ts(PERP).It consists of three sequential and interdependent modules:Colla.ora.ive student exercise gra.h(CSEG)construction,joint ra.dom walk,and recommendation list ***,CSEG is created as a unified heterogeneous gra.h with students’response behaviors and student(exercise)***,a joint ra.dom walk to take full advantage of the spectra. properties of nearly uncoupled Markov chains is performed on CSEG,which allows for full explora.ion of both simila. exercises that students have finished and connections between students(exercises)with simila. ***,we propose to optimize the recommendation list to obtain different exercise *** analyses of two public datasets,the results demonstra.ed that PERP can satisfy novelty,accura.y,and diversity.

关键词： Educational data mining Exercise recommend Joint ra.dom walk Nearly uncoupled Markov chains Optimization Personalized learning

Chi-square automatic intera.tion detection(CHAID)analysis of the use of safety goggles and face masks as personal protective equipment(PPE)to protect against occupational biohazards

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Journal of Biosafety and Biosecurity

Journal of Biosafety and Biosecurity 2024年第2期6卷 125-133页

作者： ra.l Aguila.-Elena Juán JoséAgún-González Universidad Internacional de Valencia ValenciaSpain

Background:This study represents the first Spanish investigation to rigorously evaluate compliance with the use of safety goggles and face masks as essential personal protective equipment(PPE)in companies with workpla.es involving exposure to biological ***:This study aimed to examine the degree of use of face masks and safety goggles as personal protective equipment(PPE),the factors that influence their use,and the profile of workers exposed to occupational biological agents in Spanish companies in the health sector,farming sector,meat industry,waste treatment pla.ts,food industry,and veterinary ***:We conducted a cross-sectional descriptive study involving 590 Spanish workers from 51 *** developed a 34-item questionnaire to assess workers’perception of risk rela.ed to exposure to biological agents in their *** the questions,three were designed to measure the degree of use of key protective equipment in sectors with biological agent exposure:protective gloves,safety goggles or face *** only analyzed safety goggles and face *** performed various statistical analyses,including Cronbach’s alpha,frequency of endorsement,content validity ra.io using la.she’s method,varimax rotation,the Kaiser-Meyer-Olkin test,and Bartlett’s sphericity test,to assess the internal consistency and reliability of the ***,we employed a chi-square automatic intera.tion detection(CHAID)segmentation analysis,using workers’responses regarding their attitudes toward safety goggles and face mask usage as PPE for protection against biological risks,with demogra.hic variables as independent ***:In the current study,CHAID analysis revealed that workers exposed to group 2 biological agents used more safety goggles and face shields compared with workers exposed to other groups of biological ***,workers in la.ora.ories and the food industry used face masks more than workers of other ***

关键词： PPE Safety googles and breath mask CHAID Biological Agents Occupational Biosafety