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Journal of Materiomics 2020年第2期6卷 293-299页

作者： Yong Du Jiageng Chen Qiufeng Meng Jiayue Xu Biplab Paul per eklund School of Materials Science and Engineering Shanghai Institute of Technology100 Haiquan RoadShanghai201418China Thin Film Physics Division Department of PhysicsChemistryand Biology(IFM)Link€oping UniversitySE-58183Link€opingSweden

Flexible ternary carbon black/Bi_(2)Te_(3) based alloy/polylactic acid(CB/BTBA/PLA)composites were fabricated by additive manufacturing and their thermoelectric properties were investigated from 300 K to 360 *** 300 K,as the mass ratios of BTBAs in the composites increased from 38.5% to 71.4%,both the electrical conductivity and Seebeck coefficient of the composites increased from 5.8 S/cm to 13.3 S/cm,and from 60.2 mV/K to 119.9 mV/K,respectively,and the thermal conductivity slightly increased from 0.15 W m^(-1)K^(-1) to 0.25 W m^(-1)K^(-1),as a result,the ZT value of the composites increased from 0.004 to *** the temperature increased from 300 K to 360 K,the electrical conductivity of all the composites slightly decreased,while the thermal conductivity slowly increased,and a highest ZT value of 0.024 was achieved for the composites with 71.4% BTBAs at 320 *** traditional sterolithography,fused deposition modeling,selective laser melting,etc.,this additive manufacturing process can directly print the solutions which contain inorganic fillers and polymer matrixes into almost any designed intricate geometries of thermoelectric composites,therefore this process has great potential to be used for fabrication of flexible polymer based thermoelectric composites and devices.

关键词： Flexible Bi_(2)Te_(3)based alloy Additive manufacturing Thermoelectric

Al/Mo-C中间层对锆合金表面Zr_(2)Al_(3)C_(4)涂层界面性能影响

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无机材料学报 2021年第5期36卷 541-546页

作者：叶文浩魏强梁佳敏周洁孟凡平 eklund per 黄庆天津大学材料科学与工程学院天津300350 中国科学院宁波材料技术与工程研究所新能源技术研究所宁波315201 河北工业大学机械工程学院天津300130 Department of Physics Chemistryand Biology(IFM)Linköping UniversityLinköping 58183Sweden

锆合金表面涂层研究作为提高核燃料包壳事故容错能力的重要技术手段之一,能够有效解决失水事故下锆水反应的问题。Zr_(2)Al_(3)C_(4)以其优异的抗氧化性能和适用于核环境的化学组分而成为锆合金包壳的候选涂层材料之一。由于Zr_(2)Al_(3... 详细信息

锆合金表面涂层研究作为提高核燃料包壳事故容错能力的重要技术手段之一,能够有效解决失水事故下锆水反应的问题。Zr_(2)Al_(3)C_(4)以其优异的抗氧化性能和适用于核环境的化学组分而成为锆合金包壳的候选涂层材料之一。由于Zr_(2)Al_(3)C_(4)涂层与锆合金基底之间的元素扩散以及热膨胀系数不匹配等问题,在其上制备Zr_(2)Al_(3)C_(4)涂层的相关研究较少。本研究通过磁控溅射结合后续热处理工艺,以Al/Mo-C作为扩散屏障层,在锆合金基底上制备Zr_(2)Al_(3)C_(4)涂层。结合X射线衍射仪、扫描电子显微镜和透射电子显微镜等分析手段,研究了Al/Mo-C中间层对涂层的相和微观结构的影响。结果表明,在800℃退火3 h后,未添加中间层的涂层开裂,同时由于Zr-Al-C涂层与基底之间存在明显的元素扩散,导致Zr_(2)Al_(3)C_(4)无法成相。Al/Mo-C中间层作为扩散屏障,能够有效阻止退火过程中Zr-Al-C涂层和基底之间的元素扩散,从而大大降低Zr-Al-C涂层与标准化学量比的偏差,有利于最终涂层中Zr_(2)Al_(3)C_(4)相的形成。此外,该扩散屏障层能够抑制Zr_(2)Al_(3)C_(4)涂层在退火过程中产生裂纹,同时将退火态涂层与锆合金基底的结合力提高30 N。

关键词： Zr_(2)Al_(3)C_(4) 中间层扩散屏障结合力

基于A位元素置换策略合成新型MAX相材料Ti_3ZnC_2

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无机材料学报 2019年第1期34卷 60-64页

作者：李勉李友兵罗侃 LU Jun eklund per perSSON per ROSEN Johanna HULTMAN Lars 都时禹黄政仁黄庆中国科学院宁波工业技术与工程研究所核能材料工程实验室(筹) 宁波315201 Department of Physics Chemistry and Biology (IFM) Link?ping University

MAX相材料是一类兼具金属和陶瓷特性的三元层状材料,在高温导电、耐磨、耐腐蚀和耐辐照损伤等方面性能优异。目前已经合成出的MAX相材料已有70余种,但A位元素一直局限在ⅢA和ⅣA主族元素,如Al、Si、Ga等,而以副族元素占据A位的MAX相鲜... 详细信息

MAX相材料是一类兼具金属和陶瓷特性的三元层状材料,在高温导电、耐磨、耐腐蚀和耐辐照损伤等方面性能优异。目前已经合成出的MAX相材料已有70余种,但A位元素一直局限在ⅢA和ⅣA主族元素,如Al、Si、Ga等,而以副族元素占据A位的MAX相鲜有报道。本研究以Ti_3AlC_2为前驱体,利用熔盐中的A位置换反应,制备出了A位为Zn元素的全新MAX相材料Ti_3ZnC_2。结合X射线衍射、扫描电子显微镜和透射电子显微镜等分析手段对Ti_3ZnC_2的成分和结构进行了确认,并通过密度泛函理论对Ti_3ZnC_2的结构稳定性和晶格参数进行了确定。进一步通过热力学计算对Fe、Co、Ni、Cu等几种元素的A位置换反应进行了预测,发现采用这几种元素的氧化物进行置换反应在热力学上也都具有可行性。本研究所提出的元素置换策略是在保持MAX相六方层状晶体结构的基础上,利用Al、Zn在高温下形成共晶产物实现Zn原子向A层内的迁移,而熔盐介质的存在促进了反应动力学。本方法巧妙地避免了MAX相传统合成过程中竞争相的形成,如M-A合金相,因此可以用于探索更多未知的MAX相材料。

关键词： MAX相置换反应 Ti3ZnC2

Electrochemical Lithium Storage performance of Molten Salt Derived V_(2)SnC MAX Phase

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Nano-Micro Letters 2021年第10期13卷 266-275页

作者： Youbing Li Guoliang Ma Hui Shao Peng Xiao Jun Lu Jin Xu Jinrong Hou Ke Chen Xiao Zhang Mian Li per OÅpersson Lars Hultman per eklund Shiyu Du Zhifang Chai Zhengren Huang Na Jin Jiwei Ma Ying Liu Zifeng Lin Qing Huang Engineering Laboratory of Advanced Energy Materials Ningbo Institute of Industrial TechnologyChinese Academy of SciencesNingbo 315201ZhejiangPeople’s Republic of China Qianwan Institute of CNiTECH Ningbo 315336People’s Republic of China College of Materials Science and Engineering Sichuan UniversityChengdu 610065People’s Republic of China CIRIMAT UMR CNRS 5085 UniversitéToulouse III-Paul Sabatier118 route de Narbonne31062 Toulouse Cedex 9France Department of Physics Chemistry and Biology(IFM)Linköping University58183 LinköpingSweden School of Machine Engineering Dongguan University of TechnologyDongguan 523808People’s Republic of China Institute of New Energy for Vehicles School of Materials Science and EngineeringTongji UniversityShanghai 201804People’s Republic of China

MAX phases are gaining attention as precursors of two-dimensional MXenes that are intensively pursued in applications for electrochemical energy ***,we report the preparation of V_(2)SnC MAX phase by the molten salt method.V_(2)SnC is investigated as a lithium storage anode,showing a high gravimetric capacity of 490 mAh g−1 and volumetric capacity of 570 mAh cm^(−3) as well as superior rate performance of 95 mAh g^(−1)(110 mAh cm^(−3))at 50 C,surpassing the ever-reported performance of MAX phase ***-ported by operando X-ray diffraction and density functional theory,a charge storage mechanism with dual redox reaction is proposed with a Sn-Li(de)alloying reaction that occurs at the edge sites of V_(2)SnC particles where Sn atoms are exposed to the electrolyte followed by a redox reaction that occurs at V_(2)C layers with *** study offers promise of using MAX phases with M-site and A-site elements that are redox active as high-rate lithium storage materials.

关键词： MAX phase Molten salt Lithium storage High-rate Energy storage

Iterative Subregion Correction Preconditioners with Adaptive Tolerance for Problems with Geometrically Localized Stiffness

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Communications on Applied Mathematics and Computation 2024年第2期6卷 811-836页

作者： Michael Franco per-Olof persson Will Pazner Department of Mathematics University of CaliforniaBerkeleyBerkeleyCA 94720-3840USA Fariborz Maseeh Department of Mathematics and Statistics Portland State UniversityPortlandOR 97201USA

We present a class of preconditioners for the linear systems resulting from a finite element or discontinuous Galerkin discretizations of advection-dominated *** preconditioners are designed to treat the case of geometrically localized stiffness,where the convergence rates of iterative methods are degraded in a localized subregion of the *** convergence may be caused by a number of factors,including the mesh size,anisotropy,highly variable coefficients,and more challenging *** approach taken in this work is to correct well-known preconditioners such as the block Jacobi and the block incomplete LU(ILU)with an adaptive inner subregion *** goal of these preconditioners is to reduce the number of costly global iterations by accelerating the convergence in the stiff region by iterating on the less expensive reduced *** tolerance for the inner iteration is adaptively chosen to minimize subregion-local work while guaranteeing global convergence *** present analysis showing that the convergence of these preconditioners,even when combined with an adaptively selected tolerance,is independent of discretization parameters(e.g.,the mesh size and diffusion coefficient)in the *** demonstrate significant performance improvements over black-box preconditioners when applied to several model convection-diffusion ***,we present performance results of several variations of iterative subregion correction preconditioners applied to the Reynolds number 2.25×10^(6)fluid flow over the NACA 0012 airfoil,as well as massively separated flow at 30°angle of attack.

关键词： Subregion correction Nested Krylov Geometrically localized stiffness

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鸟类形态特征的同质性比较

动物学杂志 2024年第3期59卷 321-336页

作者：郑雪星 per G.P.Ericson 屈延华中国科学技术大学生命科学与医学部合肥230026 中国科学院动物研究所动物进化与系统学院重点实验室北京100010 瑞典自然历史博物馆瑞典斯德哥尔摩50007

鸟类作为脊椎动物中的主要类群之一,其内部演化关系一直是动物学研究的重点。形态特征及分子特征在推断鸟类内部类群间的系统发育关系时被广泛应用,但长久以来受制于同质性的影响,不同形态特征难以得到一致的系统发育关系。随着基因组... 详细信息

鸟类作为脊椎动物中的主要类群之一,其内部演化关系一直是动物学研究的重点。形态特征及分子特征在推断鸟类内部类群间的系统发育关系时被广泛应用,但长久以来受制于同质性的影响,不同形态特征难以得到一致的系统发育关系。随着基因组测序技术及分析方法的快速发展,基于大量DNA序列数据所建的物种树成为领域内普遍认可的鸟类系统发育关系。在此基础之上,重新挖掘形态特征的研究价值成为可能。本研究基于Prum发表于2015年的鸟类科级水平系统发育树,比较了不同形态特征同质性水平的差异,讨论了形态特征对于提高分子特征系统发育信号及分子树支持率的作用。研究发现,不同种类形态特征的同质性水平存在显著的差异,以一致性指数为标准,杂项特征(包括神经、肌腱及肠道的特征)的得分显著高于骨学特征和肌学特征(P<0.01),颅骨特征的得分显著高于非颅骨、躯干及腿部特征的得分(P<0.05);加入形态特征能够显著提高分子特征的系统发育信号(P<0.05),也提高了分子树的支持率。综上所述,不同的形态特征在同质性水平的得分上具有显著差异,在分子特征上加入形态特征既能够提高分子特征的系统发育信号,也能够提高分子树的支持率。

关键词：形态特征同质性水平一致性指数系统发育信号支持率

On the potential of using ensemble learning algorithm to approach the partitioning coefficient(k)value in Scheil-Gulliver equation

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Materials Genome Engineering Advances 2024年第3期2卷 48-58页

作者： Ziyu Li He Tan Anders E.W.Jarfors Jacob Steggo Lucia Lattanzi per Jansson Comptech i Skillingaryd AB SkillingarydSweden Department of Materials and Manufacturing School of EngineeringJönköping UniversityJönköpingSweden Department of Computing School of EngineeringJönköping UniversityJönköpingSweden

The Scheil-Gulliver equation is essential for assessing solid fractions during alloy solidification in materials *** the prevalent use of the Calculation of Phase Diagrams(CALPHAD)method,its computational intensity and time are limiting the simulation ***,Artificial Intelligence has emerged as a potent tool in materials science,offering robust and reliable predictive modeling *** study introduces an ensemble-based method that has the potential to enhance the prediction of the partitioning coefficient(k)in the Scheil equation by inputting various alloy *** findings demonstrate that this approach can predict the temperature and solid fraction at the eutectic temperature with an accuracy exceeding 90%,while the accuracy for k prediction surpasses 70%.Additionally,a case study on a commercial alloy revealed that the model's predictions are within a 5℃deviation from experimental results,and the predicted solid fraction at the eutectic temperature is within a 15%difference of the values obtained from the CALPHAD model.

关键词： AI application partitioning coefficient scheil-gulliver equation solidification

May Traditional Chinese Medicine Reduce the Risk of Developing Rheumatoid Arthritis?An One-armed Prospective Study

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Clinical Complementary Medicine and Pharmacology 2024年第1期4卷 10-18页

作者： Kaixin Gao Qi Liang Dongyun Li Chuanning Li Maojie Wang Xiumin Chen Qingchun Huang Zehuai Wen per-Johan Jakobsson Runyue Huang The Second Affiliated Hospital of Guangzhou University of Chinese Medicine(Guangdong Provincial Hospital of Chinese Medicine) Guangzhou 510006GuangdongChina The Second Clinical Medical College Guangzhou University of Chinese MedicineGuangzhou 510006GuangdongChina State Key Laboratory of Dampness Syndrome of Chinese Medicine The Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510120GuangdongChina Guangdong Provincial Key Laboratory of Chinese Medicine for Prevention and Treatment of Refractory Chronic Diseases Guangzhou 510403GuangdongChina Guangdong-Hong Kong-Macao Joint Lab on Chinese Medicine and Immune Disease Research Guangzhou 510000GuangdongChina The key unit of methodology of clinical research The Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510000GuangdongChina Rheumatology Unit Department of Medicine SolnaKarolinska InstituteKarolinska University HospitalStockholm 17177Sweden Department of Doctor-Patient Relationship The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510630GuangdongChina

Background:Rheumatoid arthritis(RA)is a worldwide public health *** and prevention before the onset of rheumatic diseases is a new direction in current ***:The aim of this study was to evaluate the potential and feasibility of traditional Chinese medicine(TCM)in the prevention of ***:This was a single-armed prospective clinical *** participants were recruited from a single center in Guangdong,*** who were tested positive for anti-cyclic citrullinated peptide antibody(anti-CCP)and/or rheumatoid factor(RF),had no synovitis and never been treated with disease-modifying anti-rheumatic drugs(DMARDs),were enrolled to take the Huayu-Qiangshen-Tongbi(HQT)decoction orally twice daily,200 mL each time for 24 *** outcome was the proportion of patients who met 2010 ACR(American College of Rheumatology)/EULAR(European League Against Rheumatism)classification criteria of RA during *** outcomes included levels of anti-CCP,RF,erythrocyte sedimentation rate(ESR),C-reactive protein(CRP),assessment of signs and symptoms,and radiographic progression by magnetic resonance imaging(MRI).Results:19 individuals were enrolled in the study,4 of which withdrew because of the epidemic of *** the observation period,3 individuals(20%)developed RA and they had longer morning stiffness(P=0.009)and more obvious synovial enhancement in MRI(P=0.041)at baseline when compared with those who did not develop *** 24 weeks of intervention,there were improvements in 28-swollen joint count(SJC28)(P=0.046),Visual Analog Scale(VAS)(P=0.019),Patient’s Global Assessment(PtGA)(P=0.019)and Physician’s Global Assessment(PGA)(P=0.031),but no statistical significance was observed in the levels of anti-CCP,RF,ESR,CRP,morning stiffness,28-tender joint count(TJC28),Health Assessment Questionnaire(HAQ)and magnetic resonance imaging(MRI)analysis(P>0.05).Conclusion:The HQT formula is safe and could improve joint symptoms and s

关键词： Rheumatoid arthritis(RA) Prevention Traditional Chinese medicine(TCM) Huayu-Qiangshen-Tongbi decoction(HQT) Clinical trial

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湿型砂铸铝:打开新的视角

铸造 2024年第1期73卷 135-138页

作者： per Larsen Tim J.Baron 陈之伟(译) 刘溢(译) DISA Industries A/S 迪砂中国

许多汽车零部件已经用铸铝件替代以前的铸铁件。铸铝件在电动汽车的过渡中至关重要。随着汽车行业的成功转型,大批量的新型电动汽车传动系统铝部件应运而生,如电机壳和机盖。众所周知,湿型砂工艺能高效,可低成本生产出高质量的铸铁件。... 详细信息

许多汽车零部件已经用铸铝件替代以前的铸铁件。铸铝件在电动汽车的过渡中至关重要。随着汽车行业的成功转型,大批量的新型电动汽车传动系统铝部件应运而生,如电机壳和机盖。众所周知,湿型砂工艺能高效,可低成本生产出高质量的铸铁件。随着全球对铸铝件的需求不断上升,降低成本的压力不断加大,越来越多的铸造厂和制造商开始探索湿型砂生产铸铝件的运用。铸铁厂用湿型砂生产的优势成功转移到铸铝件,带来低成本、快速成形和灵活性等优点。

关键词：铸铝件湿型砂铸铁件低成本生产快速成形汽车零部件汽车传动系统电机壳

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Oxidized organic molecules in the tropical free troposphere over Amazonia

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National Science Review 2024年第1期11卷 174-184页

作者： Qiaozhi Zha Diego Aliaga Radovan Krejci Victoria A.Sinclair Cheng Wu Giancarlo Ciarelli Wiebke Scholz Liine Heikkinen Eva Partoll Yvette Gramlich Wei Huang Markus Leiminger Joonas Enroth Otso per?kyl? Runlong Cai Xuemeng Chen Alkuin Maximilian Koenig Fernando Velarde Isabel Moreno Tuukka Pet?j? Paulo Artaxo Paolo Laj Armin Hansel Samara Carbone Markku Kulmala Marcos Andrade Douglas Worsnop Claudia Mohr Federico Bianchi Institute for Atmospheric and Earth System Research/Physics University of Helsinki Joint International Research Laboratory of Atmospheric and Earth System Sciences Nanjing University Department of Environmental Science & Bolin Centre for Climate Research Stockholm University Department of Chemistry and Molecular Biology University of Gothenburg Institute for Ion and Applied Physics University of Innsbruck Ionicon Analytik GmbH Laboratory for Atmospheric Physics Institute for Physics Research Universidad Mayor de San Andrés Institute of Physics University of Sao Paulo Institute for Geosciences and Environmental Research (IGE) University of Grenoble Alpes Agrarian Sciences Institute Federal University of Uberl?ndia Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Department of Atmospheric and Oceanic Sciences University of Maryland Aerodyne Research Inc. Department of Environmental System Science ETH Zürich Switzerland and Laboratory of Atmospheric Chemistry Paul Scherrer Institute

New particle formation(NPF) in the tropical free troposphere(FT) is a globally important source of cloud condensation nuclei, affecting cloud properties and climate. Oxidized organic molecules(OOMs)produced from biogenic volatile organic compounds are believed to contribute to aerosol formation in the tropical FT, but without direct chemical observations. We performed in situ molecular-level OOMs measurements at the Bolivian station Chacaltaya at 5240 m above sea level, on the western edge of Amazonia. For the first time, we demonstrate the presence of OOMs, mainly with 4–5 carbon atoms, in both gas-phase and particle-phase(in terms of mass contribution) measurements in tropical FT air from Amazonia. These observations, combined with air mass history analyses, indicate that the observed OOMs are linked to isoprene emitted from the rainforests hundreds of kilometers away. Based on particle-phase measurements, we find that these compounds can contribute to NPF, at least the growth of newly formed nanoparticles, in the tropical FT on a continental scale. Thus, our study is a fundamental and significant step in understanding the aerosol formation process in the tropical FT.

关键词： oxidized organic molecules tropical aerosol formation Amazon free troposphere