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Shock compression and spallation damage of high-entropy alloy Al_(0.1)CoCrFeNi

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Journal of Materials Science & Technology 2022年第33期128卷 1-9页

作者： N.B.Zhang J.xu Z.D.feng Y.F.Sun J.Y.huang x.J.Zhao x.h.Yao S.Chen L.Lu S.N.Luo Key Laboratory of Advanced Technologies of Materials Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China The Peac Institute of Multiscale Sciences Chengdu 610031China Department of Engineering Mechanics South China University of TechnologyGuangzhou 510641China

Shock compression and spallation damage of a face-center cubic phase high-entropy alloy(hEA)Al_(0.1)CoCrFeNi were investigated via plate impact experiments along with free surface velocity *** samples were characterized with transmission electron microscopy and electron backscatter *** hugoniot equation of state and spall strength at different impact strengths were *** exists a power-law relation between spall strength and strain *** spall strength of Al_(0.1)CoCrFeNi hEA is about 50%higher than those of previously studied hEAs and comparable to those widely applied structural stainless steels at the same shock *** glide and stacking faults are the important deformation mechanisms in the Al_(0.1)CoCrFeNi *** are only observed at high shock *** in the Al_(0.1)CoCrFeNi hEA is ductile in *** are nucleated preferentially in grain interiors,and the intragranular voids show a strong dependence on grain boundary misorientation and peak stress.

关键词： Al_(0.1)CoCrFeNi high-entropy alloy hugoniot Spall damage Microstructure

CELLULAR SPACING SELECTION OF Al-0.53wt%Zn ALLOY UNDER NEAR-RAPID DIRECTIONAL SOLIDIFICATION CONDITION

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Acta Metallurgica Sinica(English Letters) 1998年第5期11卷 320-324页

作者： J.feng W.D.huang x.Lin T.Li Y.F.xue Y.h.Zhou Northwestern Polytechnical Univ Xi'an China

In order to investigate the response of cellular spacing to the variation of growth velocity under near-rapid directional solidification condition, Al-0.53wt%Zn alloy is directionally solidified with Bridgman apparatus. The results show that at the given temperature gradient the obtained microstrvctures are all cells and there exists a wide distribution range of cellular spacing. The maximum, λmax, minimum, λmin, and average cellular spacing, λ, as functions of growth rate, V, can be given by λmax=948.51V-0.4961, λmin= 661.16V-0.5015 and λ=412.41V-0.5049, respectively. The experimental results are compared with that predicted by KGT model, and a good agreement is found. Moreover,it is found that the average cellular spacing is also remarkably history-dependent.

关键词： Al-Zn alloy near-rapid directional solidification cellular spacing history-dependence

Structures of Isodoternifolin A and B

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Chinese Chemical Letters 1996年第9期7卷 816-817页

作者： Wang, ZM feng, h Liang, xT ChINESE ACAD TRADIT ChINESE MED INST CHINESE MAT MEDBEIJING 100700PEOPLES R CHINA ChINESE ACAD MED SCI INST MAT MEDBEIJING 100050PEOPLES R CHINA

Two new diterpenoids, named isodoternifolins A(1) and B(2), together with seven known compounds were isolated from the ethanol extract of dried stems and leaves of Isodon ternifolius (D. Don) Kudo. The structures of 1 and 2 were determined as 7 beta-hydroxy-6 beta,11 alpha,15 beta-triacetoxy-7 alpha, 20-epoxy-entkaur-16-ene and 6 beta,7 beta,15 beta-trihydroxy-11 alpha-acetoxy-7 alpha,20-epoxy-entkaur-16-ene by chemical and spectral evidence respectively.

关键词： Structures of Isodoternifolin A and B

Effect of Mo on microstructural characteristics and coarsening kinetics of γ' precipitates in Co–Al–W–Ta–Ti alloys

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Journal of Materials Science & Technology 2018年第5期34卷 799-805页

作者： h.J.Zhou F.xue h.Chang Q.feng State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing National Center for Materials Service Safety University of Science and Technology Beijing

The solvus temperature,volume fraction,coarsening behavior of γ＇ precipitates and the partitioning behavior of alloying elements as well as lattice misfit of γ/γ＇ phases influence the creep behavior of Ni-and Co-base ***,few investigations about the microstructural characteristics and the coarsening behavior of γ＇ precipitates were reported in multicomponent novel Co-base superalloys during thermal *** alloys containing different contents of molybdenum and tungsten have been investigated to explore the effect of molybdenum on γ＇ solvus temperature,γ ＋γ＇ microstructure and γ＇ coarsening in Co–Al–W–Ta–Ti-base *** results showed that the γ＇ solvus temperature decreases with the addition of *** addition reduces the Y＇ volume fractions after aging above 1000℃,but results in negligible influence on the γ＇ volume fractions aging at 900℃.Meanwhile,γ＇ coarsening is controlled by diffusion in experimental alloys after aging at 900℃ and 1000℃,and the kinetics of Y＇growth in experimental alloys are consistent with the predictions of LSW theory.

关键词： Cobalt alloys Molybdenum Coarsening Microstructure

Experimental　Investigation　of　Forced　Convective　Boiling　Flow　Instabilities　in　horizontal　helically　Coiled　Tubes

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Journal of Thermal Science 1996年第3期5卷 210-216页

作者： L. J. Guo Z. P. feng x. J. Chen N. h. Thomas National Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an China Fluid and Surface Transport Team School of Chemical Engineering The University of Birmingham Edgbaston Birmingham UK

An experimental investigation is described for the characteristics of convective boiling flow instabilities in horizontally helically coiled tubes using a steam-water two-phase closed circulation test loop at pressure from 0.5 MPa to 3.5 MPa. Three kinds of oscillation are reported: density waves; pressure drop excursions; thermal fluctuations. We describe their dependence on main system parameters such as system pressure, mass flowrate, inlet subcooling, compressible volume and heat flux. Utilizing the experimental data together with conservation constraints, a dimensionless correlation is proposed for the occurrence of density waves.

关键词： two-phase flow forced convective boiling flow instabilities horizontal helically coiled tubes experimental investigation

PERSPECTIVES IN MEChANICS OF hETEROGENEOUS SOLIDS

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Acta Mechanica Solida Sinica 2011年第1期24卷 1-26页

作者： C.Q. Chen J.Z. Cui h.L. Duan x.Q. feng L.h. he G.K. hu M.J. huang Y.Z. huo B.h. Ji B. Liu x.h. Peng h.J. Shi Q.P. Sun J.x. Wang Y.S. Wang h.P. Zhao Y.P. Zhao Q.S. Zheng W.N. Zou Department of Engineering Mechanics AML Tsinghua University Beijing 100084 China Academy of Mathematics and Systems Sciences Chinese Academy of Sciences Beijing 100190 China State Key Laboratory for Turbulence and Complex System and Department of Mechanics and Aerospace Engineering College of Engineering Peking University Beijing 100871 China CAS Key Laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of China Hefei Anhui 230026 China School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China Institute for Advanced Study Nanchang University Nanchang 330031 China Depariment of Mechanics and Engineering Sciences Fudan University 220 Handa Road Shanghai 200433 China Department of Mechanical Engineering Hong Kong University of Science and Technology Hong KongChina Department of Mechanical Engineering Hong Kong University of Science and Technology Hong Kong China Institute of Engineering Mechanics Beijing Jiaotong University Beijing 100044 China State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

The Micro- and Nano-mechanics Working Group of the Chinese Society of Theoretical and Applied Mechanics organized a forum to discuss the perspectives, trends, and directions in mechanics of heterogeneous materials in January 2010. The international journal, Acta Mechanica Solida Sinica, is de- voted to all fields of solid mechanics and relevant disciplines in science, technology, and engineering, with a balanced coverage on analytical, experimental, numerical and applied investigations. On the occasion of the 30TM anniversary of Acta Mechanica Solida Sinica, its editor-in-chief, Professor Q.S. Zheng invited some of the forum participants to review the state-of-the-art of mechanics of heterogeneous solids, with a particular emphasis on the recent research development results of Chinese scientists. Their reviews are organized into five research areas as reported in different sections of this paper. ~I firstly brings in fo- cus on micro- and nano-mechanics, with regards to several selective topics, including multiscale coupled models and computational methods, nanocrystal superlattices, surface effects, micromechanical damage mechanics, and microstructural evolution of metals and shape memory alloys. ~II shows discussions on multifield coupled mechanical phenomena, e.g., multi-fields actuations of liquid crystal polymer networks, mechanical behavior of materials under radiations, and micromechanics of heterogeneous materials. In ~III, we mainly address the multiscale mechanics of biological nanocomposites, biological adhesive surface mechanics, wetting and dewetting phenomena on microstructured solid surfaces. The phononic crystals and manipulation of elastic waves were elaborated in ~IV. Finally, we conclude with a series of perspectives on solid mechanics. This review will set a primary goal of future science research and engineering application on solid mechanics with the effort of social and economic development.

关键词： heterogeneous materials smart materials biological materials multiscale mechanics micro- and nano-mechanics damage and fracture constitutive relation elastic wave surface effects

An improvement method for the detection of insitu telomerase activity : in situ telomerase activity labeling

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World Journal of Gastroenterology 1999年第6期5卷 535-537页

作者： feng DY Zheng h Fu CY Cheng Rx hunan Med Univ Dept Pathol Changsha 410078 Hunan Province Peoples R China

INTRODUCTIONTelomerase is a special reverse transcriptase which consists of a template RNA and protein, and uses the RNA template to catalyze the addition of telomeric DNA to chromosome ends[1-5]. The enzyme is active in adult male germ-line cells, embryonic cells and hemopoietic stems, but is undetectable in normal somatic cells except for proliferative cells of renewal tissue, e.g., activated lymphocytes, basal cells of the epidermis and intestinal crypt cells, whereas in almost all malignant tumor cells and immortal cell lines, telomerase activity has been measured. Thus, it is believed that activation of telomerase is closely associated with genesis and development of malignant tumors.

关键词： methodology telomerase in situ labeling polymerase chain reaction

Electronic and magnetic structures of chain structured ironselenide compounds

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Frontiers of physics 2014年第4期9卷 465-471页

作者： Wei Li Chandan Setty x. h. Chen Jiangping hu State Key Laboratory of Functional Materials for Informatics and Shanghai Center for Superconductivity Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China Department of Physics and State Key Laboratory of Surface Physics Fudan University Shanghai 200433 China Department of Physics Purdue University West Lafayette IA 47907 USA hefei National Laboratory for Physical Science at Microscale and Department of Physics University of Science and Technology of China Hefei 230026 China Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences Beijing 100190 China

Electronic and magnetic structures of iron selenide compounds Ce2O2FeSe2 （2212＊） and BaFe2Se3 （123＊） are studied by the first-principles calculations. We find that while all these compounds are composed of one-dimensional （1D） Fe chain （or ladder） structures, their electronic structures are not close to be quasi-lD. The magnetic exchange couplings between two nearest-neighbor （NN） chains in 2212＊ and between two NN two-leg-ladders in 123＊ are both antiferromagnetic （AFM）, which is consistent with the presence of significant third NN AFM coupling, a common feature shared in other iron-chalcogenides, FeTe （11＊） and KyFe2-xSe2 （122＊）. In magnetic ground states, each Fe chain of 2212＊ is ferromagnetic and each two-leg ladder of 123＊ form a block-AFM structure. We suggest that all magnetic structures in iron-selenide compounds can be unified into an extended J1-J2-J3 model. Spin-wave excitations of the model are calculated and can be tested by future experiments on these two systems.

关键词： first-principles calculations magnetism spin-wave excitations

DRYING OF GRANULAR MATERIALS IN AGITATED FLUIDIZED BED

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Journal of hydrodynamics 2001年第2期13卷 29-31页

作者： Ma, J.h. Liu, h. feng, D.Z. Dept. of Air-Condition Eng. Shandong Inst. of Civil Eng. Jinan 250014 China

An experimental study of the drying characteristics of an agitated fluidized bed dryer is presented and discussed. In the study, the citric acid particles were used as bed material with the diameters ranging from 0.2 mm to 1.3 mm. The variables affecting apparently the drying rate were found to be the mass flow rate, the inlet air temperature, the rotary speed of agitating mechanism and the particles feed rate. Comparing with other variables considered, mass flow rate was found to have the least important influence on the drying rate. The agitated fluidized bed dryer is suitable to drying agglomerating or sticky materials.

关键词： Dryers (equipment) Drying Experiments Mass transfer