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Journal of Materials Science & Technology 2022年第36期131卷 221-230页

作者： Yaojia Ren Hong Wu Bin Liu Yong Liu Sheng Guo ZBJiao ian baker State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Department of Industrial and Materials Science Chalmers University of TechnologyGothenburg SE-41296Sweden Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China Thayer School of Engineering Dartmouth CollegeHanover NH 03755-8000United States

The present study investigated the microstructure,nanomechanics,and corrosion behavior of AlCoCuFeNi high entropy alloys fabricated by selective laser melting(SLM)and laser metal deposition(LMD).The microstructure of SLM-processed specimens was mainly composed of columnar-grained BCC matrix(^90μm in width)and Cu-rich twinned FCC *** columnar grains grew epitaxially along the building direction and exhibited a strong{001}*** comparison,a coarse columnar-grained BCC matrix(^150μm in width)with a strongertexture,rod-like B2 precipitates,and large core-shell structured FCC phases were formed in the LMD-processed specimens due to the higher heat accumulation ***,the LMD-processed specimens showed a lower hardness,wear resistance,and corrosion resistance,but higher creep resistance and reduced Young's modulus than the SLM-processed *** cracks occurred in both types of specimens,which could not be completely suppressed due to Cu segregation.

关键词： Selective laser melting Laser metal deposition High entropy alloys Nanomechanics Corrosion

微粒对多晶冰流变行为的影响——(Ⅱ)滞弹性行为

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地球物理学报 2007年第4期50卷 1156-1160页

作者：宋旼 David M Cole ian baker 中南大学粉末冶金国家重点实验室 US Army Cold Regions Research and Engineering Laboratory HanoverNH03755USA Thayer School of Engineering Dartmouth CollegeHanoverNH03755USA

用反相直接加载的方法研究了微粒对多晶冰滞弹性的影响.结果表明:在较高频率时(1Hz和10-1Hz),滞弹性应变与应力峰值呈线性关系;在较低频率时(10-2Hz),其应力/应变偏离线性关系.微粒在高频时(1Hz)通过阻碍晶界滑移对晶界弛豫产生重要影响... 详细信息

用反相直接加载的方法研究了微粒对多晶冰滞弹性的影响.结果表明:在较高频率时(1Hz和10-1Hz),滞弹性应变与应力峰值呈线性关系;在较低频率时(10-2Hz),其应力/应变偏离线性关系.微粒在高频时(1Hz)通过阻碍晶界滑移对晶界弛豫产生重要影响,增加了模量和降低了内耗.但微粒对低频时的位错弛豫没有明显的影响.通过滞弹性实验计算了非线性弛豫模型的两个重要参数,计算表明K值约为0.07Pa,α值约为0.54.

关键词：冰与冰川滞弹性弛豫模型流变

微粒对多晶冰及冰川流变行为的影响——(Ⅰ)基于位错的弛豫模型

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地球物理学报 2007年第1期50卷 126-130页

作者：宋旼 David M.Cole ian baker 中南大学粉末冶金国家重点实验室 US Army Cold Regions Research and Engineering Laboratory Hanover NH03755U.S.A. Thayer School of Engineering Dartmouth CollegeHanover NH03755U.S.A.

为量化冰及冰川在流变过程中位错密度随流变应力的变化,发展了一个基于位错的非线性弛豫模型.模型的计算表明:在冰的指数蠕变阶段,滞弹性试验所形成的应力/应变滞后环的宽度与面积随流变应力的增加呈线性增加,位错密度随流变应力的增加... 详细信息

为量化冰及冰川在流变过程中位错密度随流变应力的变化,发展了一个基于位错的非线性弛豫模型.模型的计算表明:在冰的指数蠕变阶段,滞弹性试验所形成的应力/应变滞后环的宽度与面积随流变应力的增加呈线性增加,位错密度随流变应力的增加呈平方增加;在冰的线性蠕变阶段,滞弹性试验所形成的应力/应变滞后环的宽度、面积和位错密度保持不变.

关键词：冰与冰川位错弛豫流变非线性模型

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Zr基块体非晶合金的摩擦磨损行为(英文)

Transactions of Nonferrous Metals Society of China 2012年第3期22卷 585-589页

作者：吴宏 ian baker 刘咏吴晓蓝中南大学粉末冶金国家重点实验室 Thayer School of Engineering Dartmouth CollegeHanoverNH 03755-8000U.S.A

采用销盘式摩擦实验研究Zr基块体非晶合金分别在空气与氩气环境中的摩擦磨损行为。结果表明,在16N和23N2种不同载荷下,非晶试样在氩气中的磨损量都比在空气中的低45%以上。通过X射线衍射仪、差示扫描量热分析仪、扫描电子显微镜和光学... 详细信息

采用销盘式摩擦实验研究Zr基块体非晶合金分别在空气与氩气环境中的摩擦磨损行为。结果表明,在16N和23N2种不同载荷下,非晶试样在氩气中的磨损量都比在空气中的低45%以上。通过X射线衍射仪、差示扫描量热分析仪、扫描电子显微镜和光学表面轮廓仪等检测分析手段对磨损试样摩擦面的形貌和微观结构进行表征,发现在空气中磨损试样的表面存在大量摩擦颗粒和犁沟,而氩气中的试样表面相对平滑;非晶试样的磨损机理在空气中以磨粒磨损为主,而在氩气中则为粘着磨损。

关键词：块体非晶合金摩擦磨损氧化磨损机理

Cu-Based Materials for Enhanced C_(2+) Product Selectivity in Photo-/Electro-Catalytic CO_(2) Reduction: Challenges and Prospects

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Nano-Micro Letters 2024年第4期16卷 25-66页

作者： baker Rhimi Min Zhou Zaoxue Yan Xiaoyan Cai Zhifeng Jiang Institute for Energy Research School of Chemistry and Chemical EngineeringJiangsu UniversityZhenjiang 212013People’s Republic of China School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221116People’s Republic of China

Carbon dioxide conversion into valuable products using photocatalysis and electrocatalysis is an effective approach to mitigate global environmental issues and the energy shortages. Among the materials utilized for catalytic reduction of CO_(2), Cu-based materials are highly advantageous owing to their widespread availability, cost-effectiveness, and environmental sustainability. Furthermore, Cu-based materials demonstrate interesting abilities in the adsorption and activation of carbon dioxide, allowing the formation of C_(2+) compounds through C–C coupling process. Herein, the basic principles of photocatalytic CO_(2) reduction reactions(PCO_(2)RR) and electrocatalytic CO_(2) reduction reaction(ECO_(2)RR) and the pathways for the generation C_(2+) products are introduced. This review categorizes Cu-based materials into different groups including Cu metal, Cu oxides, Cu alloys, and Cu SACs, Cu heterojunctions based on their catalytic applications. The relationship between the Cu surfaces and their efficiency in both PCO_(2)RR and ECO_(2)RR is emphasized. Through a review of recent studies on PCO_(2)RR and ECO_(2)RR using Cu-based catalysts, the focus is on understanding the underlying reasons for the enhanced selectivity toward C_(2+) products. Finally, the opportunities and challenges associated with Cu-based materials in the CO_(2) catalytic reduction applications are presented, along with research directions that can guide for the design of highly active and selective Cu-based materials for CO_(2) reduction processes in the future.

关键词： Photocatalytic CO_(2)reduction Cu-based materials Electrocatalytic CO_(2)reduction

First experience in laparoscopic surgery in low and middle income countries: A systematic review

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 546-553页

作者： Rebekka Troller Jasmine Bawa Olivia baker James Ashcroft Department of Surgery Medway Maritime HospitalGillingham ME75NYKentUnited Kingdom Department of Surgery University Hospital CambridgeCambridge CB20QQUnited Kingdom

BACKGROUND Laparoscopic surgery has reduced morbidity and mortality rates,shorter post-operative recovery periods and lower complication rates than open *** is routine practice in high-income countries and is becoming increasingly common in countries with limited ***,introducing laparoscopic surgery in low-and-middle-income countries(LMIC)can be expensive and requires resour-ces,equipment,and *** To report the challenges and benefits of introducing laparoscopic surgery in LMIC as well as to identify solutions to these challenges for countries with limited finances and *** MEDLINE,EMBASE and Cochrane databases were searched for studies reporting first experience in laparoscopic surgery in *** studies were published between 1996 and 2022 with full text available in *** criteria were studies considering only open surgery,ear,nose,and throat,endoscopy,arthro-scopy,hysteroscopy,cystoscopy,transplant,or bariatric *** Ten studies out of 3409 screened papers,from eight LMIC were eligible for inclusion in the final analysis,totaling 2497 *** reported challenges were related to costs of equipment and training programmes,equipment pro-blems such as faulty equipment,and access to surgical ***-related challenges were reliance on foreign trainers and lack of locally trained surgeons and theatre *** benefits of introducing laparoscopic surgery were economic and clinical,including a reduction in hospital stay,complications,and morbidi-ty/*** introduction of laparoscopic surgery also provided training opportunities for junior *** Despite financial and technical challenges,many studies emphasise the overall benefit of introducing laparoscopic surgery in LMICs such as reduced hospital stay and the related lower cost for *** many of the clinical centres in LMICs have proposed practical solutions to the challenges reported,more support is critical

关键词： Laparoscopic surgery Low and middle income country First experience Training in laparoscopic surgery

SiB3模式对作物区CO_2通量的模拟研究

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环境科学 2013年第10期34卷 4000-4008页

作者：张庚军卢立新蒋玲梅蒋磊 ian baker 中国科学院遥感与数字地球研究所遥感科学国家重点实验室北京100101 中国科学院大学北京100049 美国科罗拉多州立大学大气联合研究所 co80523 北京师范大学/中国科学院遥感应用研究所遥感科学国家重点实验室北京100875 北京师范大学地理学与遥感科学学院北京100875 美国科罗拉多州立大学大气科学系 co80523

以苏州东山观测站农田为对象,通过使用简单生物圈模式（SiB3）,在苏州东山站选取不同植被类型作为模式输入参数进行CO2通量的模拟,并利用苏州东山站2010-04-16~2011-06-30日的观测数据进行对比,讨论不同植被对苏州东山站CO2通量的影响.... 详细信息

以苏州东山观测站农田为对象,通过使用简单生物圈模式（SiB3）,在苏州东山站选取不同植被类型作为模式输入参数进行CO2通量的模拟,并利用苏州东山站2010-04-16~2011-06-30日的观测数据进行对比,讨论不同植被对苏州东山站CO2通量的影响.结果发现,选择玉米作为站点植被类型输入模式模拟的各月CO2通量日变化趋势与观测数据比较一致;而选择普通作物类型输入模式模拟获得的CO2通量,在4月和5月,白天低估CO2通量,6月高估CO2通量;选择茶树类型作为模式植被类型输入的模拟结果,高估5月和6月白天的CO2通量.另外,本研究还使用SiB3模式对每日CO2通量进行模拟,与观测对比后发现,选择的3种植被类型模拟获得的结果能较准确模拟出每日CO2通量的收支,但存在一定偏差.这说明,选择正确的植被类型能够使SiB3模式有效地模拟出CO2通量的日变化,但对时间从小时上升到每日尺度的CO2通量进行模拟时还存在一定困难,需要进一步验证.

关键词： SiB3 CO2通量植被类型模拟观测

SiB2和SiB3对高寒草甸和茶树地表能量通量模拟的比较

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气象学报 2013年第4期71卷 692-708页

作者：张庚军卢立新蒋玲梅蒋磊 ian baker 中国科学院遥感与数字地球研究所遥感科学国家重点实验室北京100101 中国科学院大学北京100049 美国科罗拉多州立大学大气联合研究所 CO80523 北京师范大学/中科院遥感应用研究所遥感科学国家重点实验室北京师范大学地理学与遥感科学学院北京100875 美国科罗拉多州立大学大气科学系 CO80523

运用简单生物圈模式第2版(SiB2)和第3版(SiB3),分别模拟青藏高原两个观测站(那曲、安多)和长江三角洲苏州东山观测站的近地面能量收支,并与相应观测数据进行比较研究,分析SiB2、SiB3模拟结果和观测资料产生差异的原因,以此来认识上述地... 详细信息

运用简单生物圈模式第2版(SiB2)和第3版(SiB3),分别模拟青藏高原两个观测站(那曲、安多)和长江三角洲苏州东山观测站的近地面能量收支,并与相应观测数据进行比较研究,分析SiB2、SiB3模拟结果和观测资料产生差异的原因,以此来认识上述地区地表能量收支特点。结果表明,SiB2和SiB3模拟的近地面能量通量与观测数据有较好的一致性。对感热通量,那曲和安多站SiB3比SiB2模拟的结果更接近观测资料,但苏州站SiB2模拟的结果与观测资料更吻合;对潜热通量,SiB3比SiB2模拟的日变化与观测资料更一致,SiB3的模拟结果与观测资料(除苏州站外)相关系数都在0.8以上;对地表土壤热通量,SiB2和SiB3模拟结果与观测数据相关系数都在0.8以上;对净辐射通量,SiB2和SiB3模拟结果与观测资料相关系数接近1.0。与SiB2相比,SiB3引用通用陆面模式的土壤描述并增加对冠层空间层温度、湿度和痕量气体的预报,使其能够改善潜热通量和土壤热通量的模拟,但对复杂下垫面的感热和净辐射通量模拟能力提高不明显。

关键词： SiB2 SiB3 能量通量日变化

Loss to Specialized Cardiology Follow-Up in Adults Living with Congenital Heart Disease

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Congenital Heart Disease 2024年第1期19卷 49-63页

作者： Cheryl Dickson Danielle Osborn David baker Judith Fethney David S.Celermajer Rachael Cordina Department of Cardiology Royal Prince Alfred HospitalSydneyAustralia Department of Cardiothoracic Surgery Westmead HospitalSydneyAustralia Susan Wakil School of Nursing and Midwifery The University of SydneySydneyAustralia Sydney Medical School The University of SydneySydneyAustralia

Background:Much has been written about the loss to follow-up in the transition between pediatric and adult Congenital Heart Disease(CHD)care *** less is understood about the loss to follow-up(LTF)after a successful *** is critical too,as patients lost to specialised care are more likely to experience mor-bidity and premature ***:To understand the prevalence and reasons for loss to follow-up(LTF)at a large Australian Adult Congenital Heart Disease(ACHD)***:Patients with moderate or highly complex CHD and gaps in care of>3 years(deﬁned as LTF)were identiﬁed from a comprehensive ACHD *** telephone interviews examined current care and barriers to clinic ***:Overall,407(22%)of ACHD patients(n=1842)were *** mean age at LTF was 31(SD 11.5)years and 54%were male;311(76%)were *** to adults seen regularly,lost patients were younger,with a greater socio-economic disadvantage,and had less complex CHD(pian study reports younger age,moderate complexity defects,and socio-economic disadvantage as predictive of loss to *** study highlights the need for novel approaches to patient-centered service delivery even beyond the age of transition and resources to maintain patient engagement within the ACHD service.

关键词： Loss to follow-up follow-up adult congenital heart disease lapse in care gaps in care care gaps care continuity ACHD predictors

Multiplicity dependence of the freezeout parameters in high energy hadron-hadron collisions

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Chinese Physics C 2024年第5期48卷 124-133页

作者： Muhammad Ajaz Majid Shehzad Muhammad Waqas Haifa I.Alrebdi Mohammad Ayaz Ahmad Antalov Jagnandan Shawn Jagnandan Murad Badshah Jalal Hasan baker Abdul Mosawir Quraishi Department of Physics Abdul Wali Khan University MardanMardan 23200Pakistan School of Mathematics Physics and Optoelectronic EngineeringHubei University of Automotive TechnologyShiyan 442002China Department of Physics College of SciencePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia Department of Mathematics Physics and StatisticsFaculty of Natural SciencesUniversity of Guyana101110 GeorgetownGuyananSouth America Department of Physics Faculty of ScienceUniversity of TabukTabukKingdom of Saudi Arabia Department of Electrical Engineering College of EngineeringQassim UniversityUnaizahSaudi Arabia

We examined the transverse momentum(pT)spectra of various identified particles,encompassing both light-flavored and strange hadrons(π++π−,K++K−,p+p¯,ϕ,K0s,Λ+Λ¯,Ξ−+Ξ¯+,andΩ−+Ω¯+),across different multiplicity classes in proton-proton collisions(p-p)at a center-of-mass energy of s√=7 *** the Tsallis and Hagedorn models,parameters relevant to the bulk properties of nuclear matter were *** models exhibit good agreement with experimental *** our analyses,we observed a consistent decrease in the effective temperature(T)for the Tsallis model and the kinetic or thermal freeze-out temperature(T0)for the Hagedorn model,as we transitioned from higher multiplicity(class-I)to lower multiplicity(class-X).This trend is attributed to the diminished energy transfer in higher multiplicity ***,we observed that the transverse flow velocity(βT)experiences a decline from class-I to *** normalization constant,which represents the multiplicity of produced particles,was observed to decrease as we moved toward higher multiplicity *** the effective and kinetic freeze-out temperatures,as well as the transverse flow velocity,show a mild dependency on multiplicity for lighter particles,this dependency becomes more pronounced for heavier *** multiplicity parameter for heavier particles was observed to be smaller than that of lighter particles,indicating a greater abundance of lighter hadrons compared to heavier *** particle species were observed to undergo decoupling from the fireball at distinct temperatures:lighter particles exhibit lower temperatures,while heavier ones show higher temperatures,thereby supporting the concept of multiple freeze-out ***,we identified a positive correlation between the kinetic freeze-out temperature and transverse flow velocity,a scenario where particles experience stronger collective motion at a higher freeze-out *** reason for this positive correlation is th

关键词： multiplicity dependence collective properties thermal energy