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Influence of alloy element partitioning on strength of primary α phase in Ti-6Al-4V alloy

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Journal of Materials Science & Technology 2018年第5期34卷 782-787页

作者： l.R.Zeng h.l.chen X.li l.M.lei G.P.Zhang Shenyang National laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China AVIC Commercial Aircraft Engine Co.LTD Shanghai 200241 China

The partitioning effect of Al（α-phase stabilizer） and V elements（β-phase stabilizer） on strength of the primary α phases in the α/β Ti-6 Al-4 V alloy with the bimodal microstructure was *** was found that partitioning of Al and V elements took place in the Ti-6 Al-4 V alloy during the recrystallization process,leading to the variation of the content of Al and V elements in the primary α phases with changing the volume fraction of the primary α *** tests reveal a general trend that the strength of the primary α phases increases with decreasing the volume fraction of the primary α phases,and such trend is independent on the loading direction relative to the c-axis of the α *** enhanced strength is attributed to the increase of the content of Al element in the primary α phase,but it is not dominated evidently by the change of the V *** solid solution strengthening contributed from both the elastic strain introduced by the solute atoms and the variation of the density of states was estimated theoretically.

关键词： Ti-6Al-4V Nanoindentation Strength Alloy element partitioning Crystallographic orientation

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Phase stability,electronic,elastic and thermodynamic properties of Al-RE intermetallics in Mg-Al-RE alloy:A first principles study

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Journal of Magnesium and Alloys 2015年第3期3卷 197-202页

作者： h.l.chen l.lin P.l.Mao Z.liu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

Electronic structure and elastic properties of Al_(2)Y,Al_(3)Y,Al_(2)Gd and Al_(3)Gd phases were investigated by means of first-principles calculations from CASTEP program based on density functional theory(DFT).The ground state energy and elastic constants of each phase were calculated,the formation enthalpy(Δh),bulk modulus(B),shear modulus(G),Young's modulus(E),Poisson's ratio(ν)and anisotropic coefficient(A)were *** formation enthalpy shows that Al_(2)RE is more stable than Al_(3)RE,and Al-Y intermetallics have stronger phase stability than Al-Gd *** calculated mechanical properties indicate that all these four intermetallics are strong and hard brittle phases,it may lead to the similar performance when deforming due to their similar elastic *** total and partial electron density of states(DOS),Mulliken population and metallicity were calculated to analyze the electron structure and bonding characteristics of the ***,phonon calculation was conducted,and the thermodynamic properties were obtained and further discussed.

关键词： First-principles calculation Phase stability Electronic structure Elastic properties Thermodynamic properties

Analysis of delivery and recalculation of dose using DICOM treatment records

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Radiation Medicine and Protection 2022年第3期3卷 123-130页

作者： Z.chen M.F.Moyers Y.Deng h.l.chen J.li Z.M.Shen J.lin Q.Wang P.Yepes Shanghai Proton and heavy Ion Center Shanghai Engineering Research Center of Proton and Heavy Ion Radiation TherapyShanghai Key Laboratory of Radiation OncologyShanghai 201315China Rice University HoustonTXUnited States

Objective:A procedure has been proposed for patient-specific QA that,instead of comparing a measurement to the planned dose,compares the dose calculated by an independent system to the dose calculated by the planning *** is still prudent,however,to check the accuracy of the beam *** this purpose,the DICOM records from the first treatment fraction can be compared to the planned treatment using an in-house developed planning ***:Totally 1,398 patient portals were subjected to the new QA *** dose distribution for each portal was first recalculated on a water phantom by two treatment planning systems and the dose distributions were *** agreement was observed,the patient was allowed to start treatment without a *** record from the first day was imported into an in-house planning system which was used to evaluate the delivery for errors and calculate the delivered dose distribution and compare it to the planned dose ***:A total of 266 portals passed a strict comparison between the clinical and QA dose calculations and directly used for treatment without *** those portals,the comparison of the delivery records to the plan showed that 99%of spot positions deviated less than 0.2 mm and 99.7%of spot metersets deviated by less than 0.3%.On the other hand,64 portals showed spot size deviations greater than the tolerance of15%with some as large as25%.For 32 portals in which the record was used to calculate the delivered dose distribution,the Gamma passing rates between the planned and delivered distributions were always above 95%using a 2%dose difference and 2 mm distance-to-agreement ***:The new QA process has been implemented slowly with strict *** amount of beam time required has been reduced while maintaining safety.

关键词： Ion beam Quality assurance Monte Carlo DICOM

外侧枕叶灰质容积减少与帕金森病病人的身体虚弱和认知障碍有关

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国际医学放射学杂志 2019年第4期 499-499页

作者：任彦 Y.S.chen h.l.chen C.h.lu M.h.chen K.h.Chou N.W.Tsai Department of Diagnostic Radiology Kaohsiung Chang Gung Memorial Hospital Chang Gung University College of Medicine

摘要研究帕金森病(PD)病人身体虚弱和认知下降相关的脑结构变化。方法收集61例PD病人和59例年龄和性别匹配的健康对照者。对每位入组参与者的虚弱程度均按Fried

关键词：帕金森病神经心理学测试

halogen composition and heterogeneity in the continental lithospheric mantle

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Science China Earth Sciences 2025年第1期68卷 310-314页

作者： Chunfei chen State Key laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences

1. Introduction halogens, including fluorine(F), chlorine(Cl), bromine(Br), and iodine(I), are highly mobile and water-soluble elements that can become significantly enriched in melts and fluids. In fluids and melts, halogens react with nearly all metals and readily form complexes with metal cations, significantly influencing the distribution of metal elements between different phases. Therefore, halogens play a crucial role in the migration, enrichment, and mineralization of key metals in the lithosphere(Weis et al., 2012; liu et al., 2024).

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Cyano migration-mediated radical-polar crossover cyclopropanation

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Science China Chemistry 2025年第1期68卷 241-248页

作者： Ziqiang Wang Yasu chen Jie li chen Zhu Key laboratory of Organic Synthesis of Jiangsu Province College of Chemistry Chemical Engineering and Materials ScienceSoochow University Frontiers Science Center for Transformative Molecules Zhangjiang Institute for Advanced Study and Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Shanghai Jiao Tong University

We report a novel cyano migration-mediated radical-polar crossover process, whereby both the sulfonylcyanation of aliphatic alkenes and the formation of cyclopropanes are concurrently achieved. This transformation yields a diverse array of multisubstituted cyclopropanes under mild photocatalytic conditions. Mechanistic studies elucidate that the reaction proceeds via intramolecular nucleophilic substitution, leading to the formation of the cyclopropane derivatives.

关键词： cyclopropanation cyano migration radical-polar crossover radical reactions

Two paths, one goal: mechanism of calcium homeostasis to balance plant growth and immunity

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Science China life Sciences 2025年第1期68卷 306-308页

作者： Aziz Ul Ikram Yanping Jing huan chen Jian chen International Genome Center Jiangsu University Joint Center for Single Cell Biology School of Agriculture and BiologyShanghai Jiao Tong University

Calcium(Ca2+) is an essential nutrient and a cellular signal in plants. The level of free Ca2+in the apoplast is ～10,000-fold higher than that in the cytoplasm at the resting state. This large Ca2+level gradient across the membrane between the interior and exterior can cause Ca2+overload and toxicity. Plants have evolved mechanisms to export Ca2+out of the cytoplasm or store it in intracellular organelles, such as endoplasmic reticulum（ER）, mitochondria, and vacuole.

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Efficient photocatalytic reduction of CO2 to formate by a molecular noble metal-free system

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Science China Chemistry 2025年第1期68卷 152-156页

作者： lihua Zhang lingjing chen huatian Shi Yue Wei Gui chen Tai-Chu lau School of Environment and Civil Engineering Research Center for Eco-environmental Engineering Dongguan University of Technology Department of Chemistry and Institute of Molecular Functional Materials City University of Hong Kong

Reducing CO2to carbon-neutral solar fuels can not only alleviate the energy demand but also mitigate the greenhouse *** present,developing an efficient non-noble metal photo/electrocatalytic system for converting CO2to a specific product beyond CO is still a big ***,we report a new cobalt complex bearing 2,2′-bi-1,10-phenanthroline ligand that can photocatalytically reduce CO2to formate （hCOO-）.Turnover number （TON） for hCOO-up to 677 with 99%selectivity can be achieved using organic dyes purpurin as photosensitizer and 1,3-dimethyl-2-phenyl-2,3-dihydro-1h-benzo[d]imidazole （BIh） as sacrificial reductant in a CO2-saturated NMP/TEA （v/v,3:1） solution under visible light *** potential electrolysis at-1.41 V （***/Ag Cl） in the presence of 12 m M Et3NhBF4also produced hCOO-with Faradaic efficiency of 39%.Spectroscopic and electrochemical studies suggest that a[CoI-h]species is the key intermediate for CO2reduction.

关键词： photocatalysis noble metal-free CO2 reduction formate cobalt hydride

Toward understanding the role of genomic repeat elements in neurodegenerative diseases

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Neural Regeneration Research 2025年第3期20卷 646-659页

作者： Zhengyu An Aidi Jiang Jingqi chen Institute of Science and Technology for Brain-Inspired Intelligence Fudan UniversityShanghaiChina MOE Frontiers Center for Brain Science Fudan UniversityShanghaiChina MOE Key laboratory of Computational Neuroscience and Brain-Inspired Intelligence Fudan UniversityShanghaiChina Zhangjiang Fudan International Innovation Center ShanghaiChina

Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage sequencing technology, researchers have started to notice that genomic repeat regions, previously neglected in search of disease culprits, are active contributors to multiple neurodegenerative diseases. In this review, we describe the association between repeat element variants and multiple degenerative diseases through genome-wide association studies and targeted sequencing. We discuss the identification of disease-relevant repeat element variants, further powered by the advancement of long-read sequencing technologies and their related tools, and summarize recent findings in the molecular mechanisms of repeat element variants in brain degeneration, such as those causing transcriptional silencing or RNA-mediated gain of toxic function. Furthermore, we describe how in silico predictions using innovative computational models, such as deep learning language models, could enhance and accelerate our understanding of the functional impact of repeat element variants. Finally, we discuss future directions to advance current findings for a better understanding of neurodegenerative diseases and the clinical applications of genomic repeat elements.

关键词： Alzheimer's disease ataxia deep learning long-read sequencing neurodegeneration neurodegenerative diseases Parkinson's disease repeat element structural variant

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