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Nano Research 2020年第2期13卷 401-411页

作者： fantao kong Yu Qiao Chaoqi Zhang Xiaohong Fan Aiguo kong Yongkui Shan School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200241China

Developing the highly efficient and durable non-precious metal electrocatalysts by taking advantage of inexpensive and abundant resources is of paramount importance for the widespread application of energy conversion and storage techniques such as fuel cells and metal-air ***,the sponge-like unadulterated carbontube-graphene complexes(D/G-CTs-1,000)with multifarious intrinsic defect active sites are fabricated by boric acid-hydrothermal and pyrolysis *** close contact or juncture between open nanotubes and few-layer graphene in D/G-CTs-1,000 constructs the hierarchical networks with plentifuchannels,the larger surface area and outstanding *** a result,the as-prepared D/G-CTs-1,000 electrocatalyst exhibits an excellent trifunctional electrocatalytic performance for oxygen reduction reaction(ORR),oxygen evolution reactior(OER)and hydrogen evolution reaction(HER).The primary Zn-air batteries and overall water splitting system using D/G-CTs-1,000 as the electrode materials delivers higher power density outperforming the advanced Pt/C-based batteries and the overall watersplitting performance comparable to those using the non-precious metal/carbon-based materials as *** work provides a universal and efficient synthetic strategy to produce the unadulterated carbons with high activity and long-time durability as trifunctional electrocatalysts and promote the widespread applications of metal-free electrocatalysts in sustainable energy conversior technology.

关键词： boric acid-splicing unadulterated carbon electrocatalysis rechargeable Zn-air battery overall water splitting

Impacts of agri-food e-commerce on traditional wholesale industry:Evidence from China

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Journal of Integrative Agriculture 2024年第4期23卷 1409-1428页

作者： Ruyi Yang Jifang Liu Shanshan Cao Wei Sun fantao kong Institute of Agricultural Information Chinese Academy of Agricultural SciencesBeijing 100081China Institute of Special Animal and Plant Sciences Chinese Academy of Agricultural SciencesChangchun 130112China

Rapidly expanding studies investigate the effects of e-commerce on company operations in the retail ***,the interaction between agri-food e-commerce(AEC)and the traditional agri-food wholesale industry(AWI)has not received enough attention in the existing *** on the provincial panel data from 2013 to 2020 in China,this paper examines the effect of AEC on AWI,comprising three dimensions:digitalization(DIGITAL),agrifood e-commerce infrastructure and supporting services(AECI),and agri-food e-commerce economy(AECE).First,AWI and AEC are measured using an entropy-based combination of *** results indicate that for China as a whole,AWI has remained practically unchanged,whereas AEC exhibits a significant rising ***,the findings of the fixed-effect regression reveal that DIGITAL and AECE tend to raise AWI,whereas AECI negatively affects ***,threshold regression results indicate that AECI tends to diminish AWI with three-stage inhibitory intensity,which manifests as a first increase and then a drop in the inhibition *** results suggest that with the introduction of e-commerce for agricultural product circulation,digital development will have catfish effects that tend to stimulate the vitality of the conventional wholesale industry and promote technical ***,the traditional wholesale industry benefits financially from e-commerce even while it diverts part of the traditional wholesale circulation for agricultural products.

关键词： agri-food e-commerce traditional wholesale industry panel threshold model dual-channel circulation

Electron Structure of γ/α2 Phase Boundaries in TiAl Based Alloys

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Journal of Materials Science & Technology 2003年第z1期19卷 85-87页

作者： fantao kong Ziyong CHEN Yuyong CHEN Jing TIAN Yufeng SI School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

The valence electron structure of γ/α2 phase boundaries in lamellar colonies in Ti-47Al-2M (M=Nb, Cr, V) (at. pct) was investigated by empirical electron theory of solid and molecules (EET) and its bond-length-difference (BLD) method. On this basis, the boundary condition of electron movement was employed in the improved Thomas-Fermi-Dirac (TFD) theory to decide the continuity of the electron density of the lamellar colonies interface and it is found that of γ/α2 interface is continuous. Furthermore, it is found that adding alloying elements (including Nb, Cr, and V) can improve the electron density (ρ) of γ/α2 interface, decrease Aρ of γ/α2 interface. With the electron structure analysis together with properties analysis,the effect mechanism of alloying elements (Nb, Cr, V) improving mechanical properties was explained.

关键词： TiAl based alloy, Valence electron structure, Phase boundaries, Site occupancy

Effect of V and Nb additions on microstructure,properties,and deformability of Ti-45Al-9 (V,Nb,Y) alloy

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China Foundry 2010年第4期7卷 357-361页

作者： Yang Fei kong fantao Chen Yuyong Xiao Shulong School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China Department of Powder Metallurgy. Guangzhou Research Institute of Non-ferrous Metals Guangzhou 510650 China

Ti-45Al-9(V, Nb, Y) alloys with four different x=V/Nb (atomic ratio x = 1, 1.5, 2 and 3.5) have been prepared, and the microstructures, properties and hot deformation behaviors were investigated. SEM, XRD and TEM results showed that Ti-45Al-9(V, Nb, Y) alloys were mainly composed of γ, α 2 , and β phase, and the volume fraction of β phase increased with the increase of the atomic ratio of V/Nb. The alloys were featured with lamellar microstructure with β and γ phases locating at the colony boundaries, and some β precipitates appearing at γ/γ interfaces. It was found that the colony size decreased with the increase of x. The alloys exhibited moderate mechanical properties at room temperature, with a yield strength of over 600 MPa, and fractures showed mainly translamellar character. The alloy with x=3.5 exhibited the best deformability at elevated temperature and that with x=1 had superior oxidation resistance at 800 ℃.

关键词： TiAl alloy microstructure and properties hot deformation behavior oxidation

In-situ growth and spectrum characterization of ZnSe nanocrystals in silica gel-glasses

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Chinese Science Bulletin 2004年第7期49卷 747-750页

作者： WANG Minqiang WANG Yunpeng YAO Xi kong fantao ZHANG Liangying ElectronicMaterialsResearchLaboratory(EMRL) KeyLaboratoryofEducationMinistryXi'anJiaotongUniversityXi'an710049China

ZnSe nanocrystals were in-situ grown in silica gel-glasses by using sol-gel process and the reductive thermal treatment. The transparent, homogeneous ZnSe/SiO2 nano-composites with the yellow color were first obtained. We used X-ray diffraction pattern (XRD), UV-VIS optical absorption and Raman scattering to characterize the spectrum proper-ties of ZnSe nanocrystals. The broadening of XRD peaks, the blueshift of interband optical absorption edge and the change of Raman spectrum were observed. From these experimental results, we theoretically calculated the size of ZnSe nanocrystals. The results of XRD, optical absorption and Raman spectra were approximately consistent, with the mean diameter of about 4.6 nm. The discrepancies from dif-ferent methods were discussed.

关键词：二氧化硅凝胶玻璃硒化锌纳米晶体光吸附拉曼散射溶胶-凝胶体参数限制 X-射线衍射半导体

Characterization of zirconia-based slurries with different binders for titanium investment casting

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China Foundry 2012年第2期9卷 125-130页

作者： Zhao Ertuan kong fantao Chen Yanfei Chen Ruirun Chen Yuyong National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology Harbin 150001China

The materials and physical properties of primary slurry are crucial to the surface quality of the finished castings,especially for high reactivity titanium *** aim of this study is to investigate the influence of different binders on the physical properties of primary slurry for titanium alloy investment *** zirconia-based slurries with different binders were evaluated by comparing the parameters:viscosity,bulk density,plate weight, suspensibility,gel velocity and *** results indicate that a higher viscosity of binder leads to a higher viscosity and suspensibility of slurry with the same powder/binder *** retention rate and thickness of primary layer increase with an increase in the viscosity of the slurry,and a higher retention rate is associated with a thicker primary *** gel velocity of the slurry is correlated with the gel velocity of the *** green strength and the baked strength of the primary layer are determined by the properties of the binder after gel and by the production of the binder after fired,respectively.

关键词： primary slurry binder investment casting titanium alloy

Effect of yttrium on microstructure and mold filling capacity of a near-α high temperature titanium alloy

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China Foundry 2012年第4期9卷 344-348页

作者： Zhao Ertuan Chen Yuyong kong fantao Zhang Changjiang Xiao Shulong National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China

The addition of rare earth yttrium(Y) can improve the performances of high temperature titanium alloys,such as the tensile ductility,thermal stability and creep property,***,few studies on the effect of Y on the castability of titanium alloys have been carried out,which is significant to fabrication of thin-walled complex titanium castings by investment *** this study,the microstructure and mold filling capacity of a Ti-1100 alloy with different Y additions(0,0.1wt.%,0.3wt.%,0.5wt.% and 1.0wt.%) were investigated systematically through investment casting experiments,and the casting experiments were carried out in a centrifugal titanium casting *** microstructures of the alloy were observed via the optical microscopy,scanning electron microscopy and transmission electron *** mold filling capacity was tested by using of a grid pattern and was evaluated by the number of segments completely filled by the cast *** results indicate that the grain size is decreased and the mold filling capacity is improved significantly with increasing the addition of Y from 0 to 1.0wt.%.The average primary grain size of Ti-1100 alloy is reduced from 250 μm to 50 μm and the mold filling capacity is increased from 61.5% to 100%.Considering the potential harmful effect on tensile properties of titanium alloys due to high concentrations of Y,it is suggested that Y addition should be about 0.3wt.%.

关键词： high temperature titanium alloy yttrium mold filling capacity investment casting

Improvement in collapsibility of ZrO2 ceramic mould for investment casting of TiAl alloys

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China Foundry 2011年第1期8卷 9-13页

作者： Chen Yanfei Xiao Shulong Tian Jing Xu Lijuan kong fantao Chen Yuyong School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

Investment casting has been widely recognized as the best option in producing TiAl components with key benefits of accuracy,versatility and *** collapsibility of ceramic moulds for investment casting is critical in the manufacturing process of TiAl components due to TiAl's intrinsic brittleness at room *** aim of the present research is to provide a method for production of TiAl components by investment casting in ZrO2 ceramic moulds with improved *** prepared with high polymer additions were utilized during the preparation of ceramic *** stress/strain curves obtained from green and baked ceramic moulds demonstrate that the green strength was increased with the application of high polymer,while baked strength decreased,thus the collapsibility of ceramic moulds was *** is suggested that this result is related to the burn-out of high polymer which left a lot of *** experimental findings were also verified by the investment casting of "I"-shaped TiAl components.

关键词： collapsibility improvement ZrO2 ceramic mould TiAl alloys investment casting