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中国有色金属学会会刊：英文版 2009年第3期19卷 545-551页

作者：肖璇鲁世强胡平黄铭刚 m.w.fu School of materials Science and Engineering Nanchang Hangkong University College of Electromechanical Engineering Nanjing University of Aeronautical and Astronautics Department of mechanical Engineering The Hong Kong Polytechnic University

Laves phase NbCr2 alloys with a composition of Nb-66.7Cr (molar fraction, %) were prepared by mechanical alloying and hot pressing. The microstructures and properties of the Laves phase NbCr2 alloys, prepared from elemental niobium and chromium powders under various ball milling time by hot pressing at 1 250 ℃ for 0.5 h, were investigated. The results indicate that if the ball milling time is longer than 40 h, the synthesizing reaction of Laves phase NbCr2 can be accomplished much sufficiently. Then the nearly full-dense Laves phase NbCr2 alloys can be prepared by hot pressing from ball milled powders with more than 40 h. The hot pressing sample with homogeneous and fine microstructure made from 40 h ball milled powders has the optimum microstructure and properties. It has a relative density of 98.1%, Vickers hardness of 11.4 GPa, compress strength of 1 981 mPa and fracture toughness of 4.82 mPa·m1/2. The effect of fine grain toughening is fully realized.

关键词：金合成热压性能铬元素球磨粉末

multi-scale defects in powder-based additively manufactured metals and alloys

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Journal of materials Science & Technology 2022年第27期122卷 165-199页

作者： J.fu H.Li X.Song m.w.fu Department of mechanical Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of mechanical and Automation Engineering Chinese University of Hong KongShatinHong KongChina

Defect formation is a critical challenge for powder-based metal additive manufacturing(Am).Current understanding on the three important issues including formation mechanism,influence and control method of metal Am defects should be *** this review paper,multi-scale defects in Amed metals and alloys are identified and for the first time classified into three categories,including geometry related,surface integrity related and microstructural *** particular,the microstructural defects are further divided into internal cracks and pores,textured columnar grains,compositional defects and dislocation *** root causes of the multi-scale defects are *** key factors that affect the defect formation are identified and *** detection methods and modeling of the multi-scale defects are briefly *** effects of the multi-scale defects on the mechanical properties especially for tensile properties and fatigue performance of Amed metallic components are *** control and mitigation methods for the corresponding defects,include process parameter control,post processing,alloy design and hybrid Am techniques,are summarized and *** research aspect,current research gaps and future prospects from three important aspects of the multi-scale Am defects are identified and delineated.

关键词： metal additive manufacturing multi-scale defects Detection and modeling mechanical properties Defect control and mitigation

High temperature deformation behavior and optimization of hot compression process parameters in TC11 titanium alloy with coarse lamellar original microstructure

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Transactions of Nonferrous metals Society of China 2013年第2期23卷 353-360页

作者：鲁世强李鑫王克鲁董显娟傅铭旺南昌航空大学材料科学与工程学院南昌330063 香港理工大学机械工程系

The high temperature deformation behaviors of α＋β type titanium alloy TC11 （Ti-6.5Al-3.5mo-1.5Zr-0.3Si） with coarse lamellar starting microstructure were investigated based on the hot compression tests in the temperature range of 950-1100 ℃ and the strain rate range of 0.001-10 s-1. The processing maps at different strains were then constructed based on the dynamic materials model, and the hot compression process parameters and deformation mechanism were optimized and analyzed, respectively. The results show that the processing maps exhibit two domains with a high efficiency of power dissipation and a flow instability domain with a less efficiency of power dissipation. The types of domains were characterized by convergence and divergence of the efficiency of power dissipation, respectively. The convergent domain in a＋fl phase field is at the temperature of 950-990 ℃ and the strain rate of 0.001-0.01 s^-1, which correspond to a better hot compression process window of α＋β phase field. The peak of efficiency of power dissipation in α＋β phase field is at 950 ℃ and 0.001 s 1, which correspond to the best hot compression process parameters of α＋β phase field. The convergent domain in β phase field is at the temperature of 1020-1080 ℃ and the strain rate of 0.001-0.1 s^-l, which correspond to a better hot compression process window of β phase field. The peak of efficiency of power dissipation in ℃ phase field occurs at 1050 ℃ over the strain rates from 0.001 s^-1 to 0.01 s^-1, which correspond to the best hot compression process parameters of ,8 phase field. The divergence domain occurs at the strain rates above 0.5 s^-1 and in all the tested temperature range, which correspond to flow instability that is manifested as flow localization and indicated by the flow softening phenomenon in stress-- strain curves. The deformation mechanisms of the optimized hot compression process windows in a＋β and β phase fields are identified to be spheroidizing and dynamic recrystallizing

关键词： titanium alloy coarse lamellar microstructure high temperature deformation behavior processing map hot compression process parameter optimization

基于murty判据的Ti-6.5Al-3.5mo-1.5Zr-0.3Si钛合金α+β相区热变形机制及工艺优化(英文)

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稀有金属材料与工程 2008年第4期37卷 577-583页

作者：李鑫鲁世强王克鲁傅铭旺李臻熙曹春晓南京航空航天大学江苏南京210016 南昌航空大学江西南昌330063 香港理工大学中国香港九龙红北京航空材料研究院北京100095

根据murty失稳判据，利用原始等轴组织的TC11钛合金在780～990℃和0．001～70s^-1范围内的等温恒应变速率压缩实验数据，建立了该合金的加工图。依据加工图研究了TC11钛合金的变形机制和变形缺陷与变形热力参数之间的关系。结果表明，在... 详细信息

根据murty失稳判据，利用原始等轴组织的TC11钛合金在780～990℃和0．001～70s^-1范围内的等温恒应变速率压缩实验数据，建立了该合金的加工图。依据加工图研究了TC11钛合金的变形机制和变形缺陷与变形热力参数之间的关系。结果表明，在780～990℃和0．001～0．01s^-1范围是超塑性变形区；在780～990℃和高于0．0ls^-1范围，易出现口相裂纹和空洞、局部流动以及绝热剪切等流变失稳现象。根据加工图分析，结合微观组织观察结果，并考虑变形抗力的大小，确定出了较佳的变形热力参数范围为850～940℃和0．001～0．01s^-1，最佳的变形热力参数在900℃和0．001s^-1附近。

关键词：钛合金 Ti-6.5A1-3.5mo-1.5Zr-0.3si 工艺优化 murty失稳判据变形机制

Solar evaporation for simultaneous oil-water separation and electricity generation with Janus wood-based absorbers

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 13-23页

作者： Yue Yang Ze fu Qi Zhang Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse School of Environmental and Biological EngineeringNanjing University of Science&TechnologyNanjing 210094China Key Laboratory of Industrial Ecology and Environmental Engineering(ministry of Education) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China National Laboratory of Solid State microstructures Collaborative Innovation Center of Advanced MicrostructuresCollege of Engineering and Applied SciencesKey Laboratory of Intelligent Optical Sensing and Manipulation(Ministry of Education)Jiangsu Key Laboratory of Artificial Functional MaterialsNanjing UniversityNanjing 210093China

Oily wastewater from ocean oil spills endangers marine ecosystems and human health. Therefore, developing an effective and sustainable solution for separating oil-water mixtures is urgent. Interfacial solar photothermal evaporation is a promising approach for the complete separation of two-phase mixtures using only solar energy. Herein, we report a carbonized wood-based absorber with Janus structure of comprising a hydrophobic top-layer and an oleophobic bottom-layer for simultaneous solar-driven oil-water separation and electricity generation. Under sunlight irradiation, the rapid evaporation of seawater will induce a separation of oil-water mixtures, and cause a high salt concentration region underlying the interface, while the bottom “bulk water” maintains in a low salt concentration, thus forming a salinity gradient. Electricity can be generated by salinity gradient power. Therefore, oil-water separation efficiency of > 99% and derived extra electricity power of ~0.1 w/m2 is achieved under solar radiation, demonstrating the feasibility of oil-water separation and electricity production synchronously directly using solar energy. This work provides a green and cost-effective path for the separation of oil-water mixtures.

关键词： Oily wastewater Carbonized wood Salinity gradient Electricity generation Solar irradiation

Significantly Enhanced melt memory Effect of metallocene-made Isotactic Polypropylene Containing Talc

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Chinese Journal of Polymer Science 2024年第2期42卷 213-222,I0008页

作者： Hong-wen Sun fu-Shan wang Yan Gao fu-Qing wei Jia-Chun Feng State Key Laboratory of molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China Lanzhou Petrochemical Corporation of PetroChina Lanzhou730060China Lanzhou Petrochemical Research Center Petrochemical Research Institute of PetroChinaLanzhou730060China

The melt memory effect is a widely observed phenomenon in semi-crystalline polymers. In practical applications, various additives are usually introduced into polymers, which may affect their melt memory behavior. In this work, the effect of talc on the melt memory effect of metallocene-made isotactic polypropylene(m-PP) was investigated in detail by using the differential scanning calorimetry. The results indicated that the introduction of talc significantly strengthened the melt memory effect of m-PP. Specifically, the upper limit temperature of Domain II increased from 161 ℃ to 174 ℃, resulting in a substantial widening of the temperature range of Domain IIa from 1 ℃ to 14 ℃. Analysis of the crystal orientation of the m-PP containing talc cooled from various Ts suggested that the remarkably enhanced melt memory effect could be ascribed to the stabilization of oriented nuclei facilitated by talc. This stabilizing effect was likely attributable to the prefreezing effect or the sorption interaction between talc and the m-PP chains.

关键词： metallocene-made isotactic polypropylene Talc melt memory effect Crystal orientation

Relationship between seismic structures and the diverse rupture processes of the 2023 Türkiye earthquake doublet

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Science China Earth Sciences 2024年第9期67卷 2810-2823页

作者： Zhi wANG Yi fu Shunping PEI CAS Key Laboratory of Ocean and marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Southern marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Recent geodetic and seismological observations of two major earthquakes in southeastern Türkiye in February 2023 have revealed complex rupture initiation,propagation,and segmentation along the East Anatolian Fault Zone(EAFZ)and surrounding ***,the role of upper crust structures along the EAFZ in determining the diverse rupture processes of this earthquake doublet remains *** further investigate this,we employed double-difference location and seismic tomography techniques to determine high-resolution seismic velocities(V_(P),V_(S))and Poisson’s ratio(σ)structures using a multiparameter joint tomographic *** dataset includes 100,833 high-quality source-receiver travel-time pairs of P-and *** find that the unique rupture processes of this earthquake doublet were primarily influenced by contrasting crustal seismic structures and localized geological *** m_(w)7.8 mainshock was initiated within a transitional edge zone characterized by a rigid part(asperity)of the seismogenic zone with sharp contrast variations in rock strength ranging from low to high along the *** comparison,the m_(w)7.6 rupture originated in a ductile belt featuring fluid saturation with low-VP,low-VS,and high-σvalues that extended parallel to the Cardak *** pronounced contrast structures observed along the former rupture can be attributed to the oblique collision system between the weakened section of the east Anatolian plateau and the brittle Arabian platform,while the latter rupture was initiated within the ductile structure associated with fluid intrusion caused by the northward subduction of the Cyprus slab and subsequent ***,the occurrence of the first earthquake(E1)serves to alleviate shear stress on the second earthquake(E2)fault,potentially impeding the initiation of an E2 *** the contrary,this event also significantly reduces the normal stress acting on the E2 fault due to a double left-lateral strike-slip system

关键词： 2023 Turkiye earthquake doublet Joint seismic tomography Tomographic transition edge Seismic rupture process Strong fault coupling

A high-order target phase approach for the station-keeping of periodic orbits

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Astrodynamics 2024年第1期8卷 61-75页

作者： Xiaoyu fu Nicola Baresi Roberto Armellin Surrey Space Centre University of SurreyGuildfordGU27XHUK Te PūnahaĀtea-Auckland Space Institute University of AucklandAuckland1010New Zealand

A novel high-order target phase approach(TPhA)for the station-keeping of periodic orbits is proposed in this *** key elements of the TPhA method,the phase-angle Poincare map and high-order maneuver map,are constructed using differential algebra(DA)techniques to determine station-keeping epochs and calculate correction maneuvers.A stochastic optimization framework tailored for the TPhA-based station-keeping process is leveraged to search for fuel-optimal and error-robust TPhA ***-satellite orbits(QSOs)around Phobos are investigated to demonstrate the efficacy of TPhA in mutli-fidelity dynamical *** Carlo simulations demonstrated that the baseline QSO of JAXA’s martian moons eXploration(mmX)mission could be maintained with a monthly maneuver budget of approximately 1 m/s.

关键词： target phase approach(TPhA) station-keeping Poincarémap differential algebra(DA) quasi-satellite orbit(QSO)

Transcriptomic and machine learning analyses identify hub genes of metabolism and host immune response that are associated with the progression of breast capsular contracture

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Genes & Diseases 2024年第3期11卷 427-437页

作者： Yukun mao Xueying Hou Su fu Jie Luan Breast Plastic and Reconstructive Surgery Center Plastic Surgery HospitalChinese Academy of Medical SciencesPeking Union Medical CollegeBeijing 100144China

Capsular contracture is a prevalent and severe complication that affects the post-operative outcomes of patients who receive silicone breast *** present,prosthesis replacement is the major treatment for capsular contracture after both breast augmentation procedures and breast reconstruction following breast cancer ***,the mecha-nism(s)underlying breast capsular contracture remains *** study aimed to identify the biological features of breast capsular contracture and reveal the potential underlying mechanism using RNA *** tissues from 12 female patients(15 breast capsules)were divided into low capsular contracture(LCC)and high capsular contracture(HCC)groups based on the Baker ***,41 lipid metabolism-related genes were identified through enrichment analysis,and three of these genes were identified as candidate genes by SVm-RFE and LASSO *** then compared the proportions of the 22 types of im-mune cells between the LCC and HCC groups using a CIBERSORT analysis and explored the Cor-relation between the candidate hub features and immune ***,PRKAR2B was positively correlated with the differentially clustered immune cells,which were m1 macro-phages and follicular helper T cells(area under the ROC=0.786).In addition,the expression of PRKAR2B at the mRNA or protein level was lower in the HCC group than in the LCC *** molecular mechanisms were identified based on the expression levels in the high and low PRKAR2B *** findings indicate that PRKAR2B is a novel diagnostic biomarker for breast capsular contracture and might also influence the grade and progression of capsularcontracture.

关键词： Biomarker Breastcapsular contracture Immune infiltration machinelearning algorithms PRKAR2B

Numerical simulation of granular silicon growth and silicon fines formation process in polysilicon fluidized bed

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Particuology 2024年第4期87卷 74-86页

作者： Guangkai Gu Guoqiang Lv wenhui ma Shanlin Du Boqiang fu Faculty of metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Complex Nonferrous metal Resources Cleaning Utilization in Yunnan Province Kunming 650093China

Operating conditions strongly affect the yield and quality of polysilicon in a polysilicon fluidized *** this study,a new model of polysilicon fluidized bed was established using the Euler-Euler model coupled with population balance model(PBm),which was combined with fluid flow,heat,and mass transfer models,while considering the scavenging effect of silicon *** effects of different operating conditions on the deposition and formation rates of silicon fines were *** show that the model can correctly describe the particle growth process in the fluidized bed of *** silicon fines and the interphase velocity difference show"N"-and"m"-shaped distributions along the axial direction,*** particle temperature and concentration near the wall are higher than those in the central *** decomposition of silane in the bottom region of the bed is dominated by het-erogeneous *** scavenging of silicon fines occurs in the dilute-phase *** effects of operating conditions,*** gas temperature,silane composition,and gas velocity,on the reactor performance were also explored *** the inlet gas composition and velocity enhances the formation rates of solid silicon and *** the inlet gas temperature promotes the growth of solid silicon and inhibits the formation of silicon *** fluidization ratio,low inlet silane concentration,and high inlet gas temperature enhance the selectivity of silicon growth.

关键词： Polysilicon fluidized bed Particle growth Fines CFD Population balance model(PBm)