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Journal of Materials Science & technology 2018年第10期34卷 1719-1729页

作者： X.B. Yang J.H. Chen G.H. Zhang L.P. Huang t.w. fan Y. Ding X.w. Yu Center for High-Resolution Electron Microscopy College of Materials Sdence and Engineering Hunan University Changsha Hunan 410082 China Department of Applied Physics School of Physics and Electronics Hunan University Changsha Hunan 410082 China

By Using （scanning） transmission electron microscopy, localized-corrosion morphology variations of the AA7055 AIZn（Cu）Mg alloy with different thermal processes and their underlying microscopic causes were investigated systematically. Our study shows that the corrosion resistance of the nanoscale precipitates varies with their structure type and Cu-content. Just like the Al-matrix, the early-stage precipitates are corrosion resistant, as compared with the ηp/η-precipitates without high Cu-content. with a high Cu-content, however, the η-precipitates become most corrosion resistant among all phases involved. Hence, tailoring the precipitate microstructure and chemistry though thermal processes may change the overall corrosion morphology and improve corrosion resistance property of the alloy.

关键词： Aluminum alloys Precipitates Corrosion Electron microscopy

A micromechanical model based on hypersingular integro-differential equations for analyzing micro-crazed interfaces between dissimilar elastic materials

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Applied Mathematics and Mechanics(English Edition) 2020年第2期41卷 193-206页

作者： X.wANG w.t.ANG H.fan School of Mechanical and Aerospace Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore

the current.w.rk models a weak(soft) interface between two elastic materials as containing a periodic array of micro-crazes. the boundary conditions on the interfacial micro-crazes are formulated in terms of a system of hypersingular integro-differential equations with unknown functions given by the displacement jumps across opposite faces of the micro-crazes. Once the displacement jumps are obtained by approximately solving the integro-differential equations, the effective stiffness of the micro-crazed interface can be readily computed. the effective stiffness is an important quantity needed for expressing the interfacial conditions in the spring-like macro-model of soft interfaces. Specific case studies are conducted to gain physical insights into how the effective stiffness of the interface may be influenced by the details of the interfacial micro-crazes.

关键词： micromechanical modeling micro-crazed interface effective stiffness coefficient hypersingular integro-differential equation

Evaluation of natural goethite on the removal of arsenate and selenite from water

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Journal of Environmental Sciences 2019年第2期31卷 133-141页

作者： Andrew t.Jacobson Maohong fan Department of Chemical Engineering University of Wyoming

Elevated arsenic and selenium concentrations in water cause health problems to both humans and wildlife. Natural and anthropogenic activities have caused contamination of these elements in waters worldwide, making the development of efficient cost-effective methods in their removal essential. In this work, removal of arsenate and selenite from water by adsorption onto a natural goethite(α-FeO OH) sample was studied at varying conditions. the data was then compared with other arsenate, selenite/goethite adsorption systems as much of literature shows discrepancies due to varying adsorption conditions. Characterization of the goethite was completed using inductively coupled plasma mass spectrometry, X-ray diffraction, Fouriertransform infrared spectroscopy, scanning electron microscopy, and Brunauer–Emmett–teller surface area analysis. Pseudo-first order(PFO) and pseudo-second order(PSO) kinetic models were applied; including comparisons of different regression methods. Various adsorption isotherm models were applied to determine the best fitting model and to compare adsorption capacitates with other works. Desorption/leaching of arsenate and selenite was studied though the addition of phosphate and hydroxyl ions. Langmuir isotherm modeling resulted in maximum adsorption capacities of 6.204 and 7.740 mg/g for arsenate and selenite adsorption,respectively. the PSO model applied with a non-linear regression resulted in the best kinetic fits for both adsorption and desorption of arsenate and selenite. Adsorption decreased with increasing pH. Phosphate induced desorption resulted in the highest percentage of arsenate and selenite desorbed, while hydroxide induced resulted in the fastest desorption kinetics.

关键词： Arsenic Selenium Adsorption Desorption FeOOH water treatment

Clinicopathological and prognostic implications of endoglin (CD105) expression in hepatocellular carcinoma and its adjacent non-tumorous liver

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world Journal of Gastroenterology 2005年第2期11卷 176-181页

作者： Joanna w.Ho Ronnie t.Poon Chris K.Sun Sheung-tat fan Centre tor the Study of Liver Disease and Departments of Surgery and PathologyThe University of Hong KongPokfulam Hong Kong China

AIM: the expression pattern of endoglin (CD105) in hepatocellular carcinoma (HCC) has not been reported so far. we hypothesized that CD105 could differentially highlight a subset of microvessels in HCC, and intratumoral microvessel density (IMVD) by CD105 immunostaining (IMVD-CD105) could provide better prognostic information than IMVD by CD34 immunostaining (IMVD-CD34).MEtHODS: Paraffin blocks of tumor and adjacent nontumorous liver tissues from 86 patients who underwent curative resection of HCC were used for this study. Serial sections were stained for CD105 and CD34, respectively,to highlight the microvessels. IMVD was counted according to a standard ***: In the HCC tissues, CD105 was either negatively or positively stained only in a subset of microvessels. In contrast, CD34 showed positive and more extensive microvessel staining in all cases examined. However, in the adjacent non-tumorous liver sections, CD105 showed a diffuse pattern of microvessel staining in 20 of 86 cases,while CD34 showed negative or only focal staining of the sinusoids around portal area. Correlation with clinicopathological data demonstrated that lower scores of IMVD-CD105 were found in larger sized tumors [mean 41.4/0.74 mm2 (＞5 cm tumor) vs 65.9/0.74 mm2(≤ 5 cm tumor), P = 0.043] and more aggressive tumors,as indicated by venous infiltration [36.8/0.74 mm2 (present)vs 64.2/0.74 mm2 (absent), P = 0.020], microsatellite nodules [35.1/0.74 mm2 (present) vs 65.9/0.74 mm2(absent), P = 0.012], and advanced tNM tumor stage [38.8/0.74 mm2 (stage 3 or 4) vs 68.3/0.74 mm2 (stage 1or 2), P = 0.014]. No prognostic significance was observed when median values were used as cut-off points using either IMVD-CD105 or IMVD-CD34. However, the presence of the diffuse pattern of CD105 expression in the adjacent non-tumorous liver tissues predicted a poorer disease-free survival (median 8.6 vs 21.5 mo, P = 0.026).CONCLUSION: Our data demonstrate that a lower IMVDCD105 is associated with larger

关键词： Hepatocellular carcinoma Endoglin Intratumoral microvessel density

Search for potential K ion battery cathodes by first principles

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Journal of Energy Chemistry 2021年第3期30卷 377-385页

作者： Kaining Li Xiaofeng fan David J.Singh wtZheng Key Laboratory of Automobile Materials(Jilin University) Ministry of Educationand College of Materials Science and EngineeringJilin UniversityChangchun 130012JilinChina Department of Physics and Astronomy University of MissouriColumbiaMO 65211-7010USA Department of Chemistry University of MissouriColumbiaMO 65211USA State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130012JilinChina

An important challenge facing K-ion batteries lies in exploring earth-abundant and safe cathode materials that can provide high capacity with high migration rate of K ***,we propose a simple and efficient method for searching potential K cathode materials with first principles *** screening is based on combinations of weight capacity,K ion occupation ratio,volume change per K,and valence *** this screening method we predicted a series of potential K ions cathodes with favorable electrochemical performance,such as K_(2)VPO_(4)CO_(3)-like structures with 1 D diffusion channels,3 D channel structures K_(2)CoSiO_(4),layered materials KCoO_(2),KCrO_(2),KVF_(4) and K_(5)V_(3)F_(14),and *** potential cathodes have small volume changes,suitable voltage,and high capacity,with small diffusion *** may be useful in K-ion batteries with high energy density and rate performance.

关键词： K ion battery Cathodes First principles calculations High capacity with high migration rate Diffusion barriers

MOF-derived ZrO_(2)/C-polyvinylidene fluoride composite t.w.rds negative permittivity regulation mechanism

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Journal of Materials Science & technology 2024年第12期179卷 50-56页

作者： X.t.Song G.H.fan Y.Liu R.H.fan Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Jinan 250061China Institute of Advanced Electrical Materials Qingdao University of Science&TechnologyQingdao 266042China College of Ocean Science and Engineering Shanghai Maritime UniversityShanghai 201306China

Composites featuring negative permittivity have garnered significant attention for their potential in novel capacitance designs,coil-less electrical inductors,and electromagnetic shielding *** this study,we prepared polyvinylidene fluoride(PVDF)matrix composites filled with ZrO_(2)/C nanoparticles de-rived from metal-organic frameworks(MOFs)via a hot-pressing *** an increase in the ZrO_(2)/C content to 30 wt.%,electrical percolation was observed,accompanied by a transition mechanism from hopping conduction to metal-like *** enabled the realization of ZrO_(2)/C/PVDF composites with tailorable negative permittivity properties,attributed to the plasmonic oscillation of free electrons in the composites beyond the percolation threshold(30 wt.%).Furthermore,the permittivity transition along to a shift in the electrical behavior of the percolative composites from capacitive to *** explored the regulatory mechanism behind the negative permittivity in this random composite system,and our findings highlight the potential of these tunable negative permittivity media as promising candi-dates for diverse electromagnetic applications.

关键词： Negative permittivity Electrical properties Plasma oscillation Polymeric composites

Coupled simulation of BES-CFD and performance assessment of energy recovery ventilation system for office model

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Journal of Central South University 2012年第3期19卷 633-638页

作者： Yunqing fan t.Hayashi K.Ito Interdisciplinary Graduate School of Engineering Science(IGSES) Kyushu University

thermal comfort and indoor air quality as well as the energy efficiency have been recognized as essential parts of sustainable building assessment. this work aims to analyze the energy conservation of the heat recovery ventilator and to investigate the effect of the air supply arrangement. three types of mixing ventilation are chosen for the analysis of coupling ANSYS/FLUENt （a computational fluid dynamics （CFD） program） with tRNSYS （a building energy simulation （BES） software）. the adoption of mutual complementary boundary conditions for CFD and BES provides more accurate and complete information of indoor air distribution and thermal performance in buildings. A typical office-space situated in a middle storey is chosen for the analysis. the office-space is equipped with air-conditioners on the ceiling. A heat recovery ventilation system directly supplies flesh air to the office space. Its thermal performance and indoor air distribution predicted by the coupled method are compared under three types of ventilation system. when the supply and return openings for ventilation are arranged on the ceiling, there is no critical difference between the predictions of the coupled method and BES on the energy consumption of HVAC because PID control is adopted for the supply air temperature of the occupied zone. On the other hand, approximately 21% discrepancy for the heat recovery estimation in the maximum between the simulated results of coupled method and BES-only can be obviously found in the floor air supply ventilation case. the discrepancy emphasizes the necessity of coupling CFD with BES when vertical air temperature gradient exists. Our future target is to estimate the optimum design of heat recovery ventilation system to control CO2 concentration by adjusting flow rate of flesh air.

关键词： building energy simulation computational fluid dynamics (CFD) FLUENt tRNSYS energy saving

Gas-solid coupling laws for deep high-gas coal seams

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International Journal of Mining Science and technology 2017年第4期27卷 675-679页

作者： Zhou Aitao wang Kai fan Lingpeng t.A. Kiryaeva Beijing Key Laboratory for Precise Mining of lntergrown Energy and Resources China University of Mining & Technology Beijing 100083 China School of Resource & Safety Engineering State Key Laboratory of Coal Resources and Mine Safety China University of Mining & Technology Belting 100083 China Chinakal Institute of Mining Siberian Branch Russian Academy of Sciences Krasnyi pr. 54 Novosibirsk 630091 Russia

A better understanding of gas-solid coupling laws for deep, gassy coal seams is vital for preventing the compound dynamic disasters such as rock burst and gas outburst. In this paper, a gas-solid coupling theoretical model under the influence of ground stress, gas pressure, and mining depth is established and simulated by using COMSOL Multiphysics software. Research results indicate that under the influence of factors such as high ground stress and gas pressure, the mutual coupling interaction between coal and gas is much more significant, which leads to the emergence of new characteristics of gas compound dynamic disasters. Reducing the ground stress concentration in front of the working face can not only minimize the possibility of rock burst accidents, which are mainly caused by ground stress, but also can weaken the role of ground stress as a barrier to gas, thereby decreasing the number of outburst accidents whose dominant factor is gas. the results have a great theoretical and practical significance in terms of accident prevention, enhanced mine safety, disaster prevention system design, and improved accident emergency plans.

关键词： Deep mining Gassy coal seam Gas-solid coupling Dynamic disaster

Light tuning CO/H_(2)composition on Ag:Unraveling CO_(2)mass transfer and electron-phonon coupling in plasmon-enhanced electrocatalysis

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Nano Research 2025年第1期18卷 173-185页

作者： Rui Lin Dong fan Luca MBerger thomas Possmayer Yu Zhou Jiexin Zhu Xingbao Chen wen Luo Lars Allmendinger Andreas tittl Leonardo de Souza Menezes Guillaume Maurin Shihe Yang and Stefan AMaier Nanoinstitute Munich Faculty of PhysicsLudwig-Maximilians-Universität München80539 MunichGermany Institut Charles Gerhardt Montpellier UMR 5253 CNRS ENSCM UniversitéMontpellierPlace E.Bataillon34090 MontpellierFrance Guangdong Provincial Key Lab of Nano-Micro Material Research School of Advanced MaterialsPeking University Shenzhen Graduate SchoolShenzhen 518055China State Key Laboratory of Advanced technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Faculty of Chemistry and Pharmacy Ludwig-Maximilians-Universität München81377 MunichGermany Departamento de Física Universidade Federal de Pernambuco50670-901 Recife-PEBrazil School of Physics and Astronomy Monash University Clayton CampusMelbourneVictoria 3800Australia Department of Physics Imperial College LondonSW72AZ LondonUK

Plasmon-enhanced electrocatalysis(PEEC)is an emerging approach to mitigate CO_(2)*** mechanisms behind CO_(2)adsorption and reduction at the catalyst-electrolyte interface in PEEC still need to be further ***,we employ a well-defined Ag nanostructure to elucidate these pivotal *** shining light.w.th wavelengths of 625,525,405 nm on Ag,an adjustable CO/H_(2)ratio from 35 to 1 can be *** reaction pat.w.y changing under plasmonic excitation does not originate from the lowered CO_(2)mass transfer in the vicinity of Ag,as the electrochemical quartz crystal microbalance results unravel that a slightly elevated temperature in bulk electrolyte caused by light irradiation cannot.w.aken the CO_(2)adsorption at the Ag catalyst-electrolyte *** calculations reveal that optical excitation t.w.rds shorter wavelengths leads to a progressive lowered energy barrier for H_(2)formation together with an enhanced energy barrier for^(*)COOH *** thermodynamically suppressed,CO_(2)reduction can still be improved kinetically by optimizing the excitation wavelength and intensity,being accompanied with the enhanced *** absorption spectroscopy results further correlate the higher photocurrent.w.th a prolonged electron-phonon coupling time,verifying that the improvement of CO_(2)reduction kinetics in PEEC can be realized by hot electron harnessing.

关键词： plasmonic catalysis photoelectrochemical CO_(2)reduction CO/H_(2)ratio hot electron generation electronphonon coupling thermal effect

Enhancing strength and creep resistance of Mg-Gd-Y-Zn-Zr alloy by substituting Mn for Zr

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Journal of Magnesium and Alloys 2019年第3期7卷 388-399页

作者： C.Xu t.Nakata G.H.fan X.w.Li G.Z.tang S.Kamado School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001PR China Department of Mechanical Engineering Nagaoka University of TechnologyNagaoka 940-2188Japan School of Material Science and Engineering Harbin University of Science and TechnologyHarbin 150040PR China

the age-hardening behavior and mechanical properties of the extruded Mg-2Gd-1.2Y-0.5Zn(at.%)alloy with Zr or Mn additions were *** results show that Mn added alloy exhibits more remarkable age-hardening response than Zr added alloy,which is attributed to the fact that partitioning of Mn into the β'phases,β'precipitates and long period stacking ordered(LPSO)phases leads to the decrement in(G d+Y)concentrations in the second phases,facilitating the precipitation during aging *** peak-aged alloys show bimodal microstructure comprising the fine DRXed grains with nano-sized β phases pinned at DRXed grain boundaries as well as coarse worked grains with strong fiber *** strength and good thermal stability were obtained in both peak-aged Mn and Zr added *** the peak-aged Mn added alloy shows higher strength and superior creep resistance due to its denser β'precipitates,thin LPSO phases and γ'precipitates and higher area fraction of worked grains with strong fiber *** 0.2% tensile proof stress and ultimate tensile strength of peak-aged Mn added alloy reach up to 454 MPa and 508 MPa,respectively,with elongation of 3.2%at room *** minimum creep rate of the peak-aged Mn added alloy at 250℃/150 MPa is 2.4 × 10^-8 s^-1,which is superior than previously reported extruded Mg-Gd based alloys.

关键词： Magnesium alloys Rare earth(RE) Precipitation Mechanical properties Creep resistance