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Acta metallurgica Sinica(English Letters) 2003年第3期16卷 192-196页

作者： S.m.Han m.S.zhao Y.z.zeng Department of Environmental and Chemical Engineering Yanshan University Qinhuangdao 066004China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied Chemistry The Chinese Academy of SciencesChangchun 130022 ChinaDepartment of Environmental and Chemical Engineering Yanshan University Qinhuangdao 066004China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied Chemistry The Chinese Academy of SciencesChangchun 130022 ChinaDepartment of Environmental and Chemical Engineering Yanshan UniversityQinhuangdo 066004 China

The crystal structure, the phase composition and the electrochemical characteristics of zr0.9Ti0.1(Ni1.1mn0.7V0.2)x (x=0.90, 0.95, 1.00, 1.05) alloys were investigated by means of XRD, SEm, EDS and electrochemical measurements. It was shown that all alloys are multiphase with C15 Laves phase as a main phase along with C14 phase and some secondary phases. And the amounts of the C14 phase and secondary phases in the four alloys increases with decreasing x. The results indicated that the various stoichiometric ratios have great effects on the electrochemical characteristics such as the maximum discharge capacity, discharge rate capability and self-discharge properties etc. for zr0.9Ti0.1(Ni1.1mn0.7 V0.2)X (x=0.90, 0.95, 1.00, 1.05) alloys. The hyper-stoichiometric zr0.9 Ti0.1(N1.1mn0.7 V0.20)1.05 exhibits the maximum discharge capacity of 332mAh-g-1. The C14 phase and secondary phases seems to improve discharge rate capability of the alloys.

关键词： metal hydride electrode microstructure electrochemical characteristics non-stoichiometric ratio

Thermal Product of Type-E Fast Response Temperature Sensors

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Journal of Thermal Science 2010年第4期19卷 364-371页

作者： H.A.mohammed H.Salleh m.z.Yusoff Antonio Campo Department of mechanical Engineering College of EngineeringUniversiti Tenaga NasionalKm 7Jalan Kajang-Puchong43009 KajangSelangorMalaysia Department of mechanical Engineering The University of Texas at San AntonioSan AntonioTX 78249USA

This paper provides practical data for thermal product values of different scratched temperature sensors that can be used for accurate transient heat transfer measurements under hypersonic flow *** effect of using different scratch techniques(abrasive papers and scalpel blades)to form the sensor's junction is *** was observed that the thermal product of a particular sensor depends on the mach number,junction scratch technique, junction location and enthalpy *** was demonstrated that using different scratched technique would produce different thermal product values.

关键词： thermal product fast response temperature sensor hypersonic flow.

Structural & magnetic Characterizations of NiLizn Nanoferrites Synthesized by Co-precipitation method

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Journal of materials Science & Technology 2011年第11期27卷 991-995页

作者： D.N. Rohadiana z.A.z. Jamal S.B. Jamaludin m.F. Bari J. Adnan Sustainable Engineering Research Cluster Universiti Malaysia Perlis School of microelectronic Engineering Universiti Malaysia Perlis

Synthesis of ***（0.5-x）Fe204 nanoparticles with x=0, 0.1, 0.2, 0.3, 0.4 and 0.5 were realized via coprecipitation method. X-ray diffraction （XRD） and vibrating sample magnetometer （VSm） measurements were performed on the samples to determine the characteristics of the crystal structures and the magnetic properties of the samples, respectively. The spinel phase structures of the samples were confirmed by XRD analysis. Patterns of decreased lattice parameter and increased crystallite size values were observed by increasing the Li concentration at longer synthesis reaction periods. Similarly, for the magnetic properties, both the saturation magnetization （ms） and coercivity （Hc） were found to vary with increasing patterns at higher Li doping levels and longer synthesis reaction periods. The results and mechanisms concerned were discussed.

关键词： Lithium nickel zinc ferrite Co-precipitation Crystal structure magnetic properties

Solving Nonlinear Fractional Differential Equation by Generalized mittag-Leffler Function method

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Communications in Theoretical Physics 2013年第6期59卷 661-663页

作者： A.A.m.Arafa z.Rida A.A.mohammadein H.m.Ali Department of mathematics and Computer Science Faculty of Science Port Said University Department of mathematics Faculty of Science South Valley University Department of mathematics Faculty of Science Aswan University

In this paper, we use mittag-Leffler function method for solving some nonlinear fractional differential equations. A new solution is constructed in power series. The fractional derivatives are described by Caputo's se... 详细信息

关键词： nonlinear fractional differential equations mittag-Leffler function Caputo fractional derivative

microstructure and mechanical Properties of X80 Pipeline Steel Joints by Friction Stir Welding Under Various Cooling Conditions

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Acta metallurgica Sinica(English Letters) 2020年第1期33卷 88-102页

作者： G.m.Xie R.H.Duan P.Xue z.Y.ma H.L.Liu z.A.Luo State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

X80 pipeline steel plates were friction stir welded(FSW)under air,water,liquid CO2+water,and liquid CO2 cooling conditions,producing defect-free *** microstructural evolution and mechanical properties of these FSW joints were *** granular bainite was observed in the nugget zone(Nz)under air cooling,and lath bainite and lath martensite increased signifi cantly as the cooling medium temperature *** particular,under the liquid CO2 cooling condition,a dual phase structure of lath martensite and fi ne ferrite appeared in the *** to the case under air cooling,a strong shear texture was identifi ed in the Nzs under other rapid cooling conditions,because the partial deformation at elevated temperature was retained through higher cooling *** liquid CO2 cooling,the highest transverse tensile strength and elongation of the joint reached 92%and 82%of those of the basal metal(Bm),respectively,due to the weak tempering softening.A maximum impact energy of up to 93%of that of the Bm was obtained in the Nz under liquid CO2 cooling,which was attributed to the operation of the dual phase of lath martensite and fi ne ferrite.

关键词： Friction stir welding Pipeline steel microstructure mechanical properties Cooling

Lignite-Derived Humic Acid Effect on Growth of Wheat Plants in Different Soils

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Pedosphere 2011年第1期21卷 124-131页

作者： m.m.TAHIR m.KHURSHID m.z.KHAN m.K.ABBASI m.H.KAzmI Department of Soil and Environmental Sciences Faculty of AgricultureUniversity of Azad Jammu and Kashmir Land Resource Research Programme National Agriculture Research Centre Department of Agronomy Faculty of AgricultureUniversity of Azad Jammu and Kashmir

Humic acid （HA）, a fairly stable product of decomposed organic matter that consequently accumulates in ecological systems, enhances plant growth by chelating unavailable nutrients and buffering pH. We examined the effect of HA derived from lignite on growth and macronutrient uptake of wheat （Triticum acstivum L.） grown in earthen pots under greenhouse conditions. The soils used in the pot experiment were a calcareous Haplustalf and a non-calcareous Haplustalf collected from Raisalpur and Guliana, respectively, in Punjab Province, Pakistan. The experiment consisted of four treatments with HA levels of 0 （control without HA）, 30, 60, and 90 mg kg^-1 soil designated as HA0, HA1, HA2, and HA3, respectively. In the treatment without HA （HA0）, nitrogen （N）, phosphorus （P）, and potassium （K） were applied at 200, 100, and 125 mg kg^-1 soil, respectively. Significant differences among HA levels were recorded for wheat growth （plant height and shoot weight） and N uptake. On an average of both soils, the largest increases in plant height and shoot fresh and dry weights were found with HA2 （60 mg kg^-1 soil）, being 10%, 25%, and 18%, respectively, as compared to the control without HA （HA0）. Both soils responded positively towards HA application. The wheat growth and N uptake in the non-calcareous soil were higher than those of the calcareous soil. The HA application significantly improved K concentration of the non-calcareous soil and P and NO3-N of the calcareous soil. The highest rate of HA （90 mg kg^-1 soil） had a negative effect on growth and nutrient uptake of wheat as well as nutrient accumulation in soil, whereas the medium dose of HA （60 mg kg^-1 soil） was more efficient in promoting wheat growth.

关键词： calcareous soil NO3-N nutrient uptake plant height soil nutrient

Detailed analysis of the relativistic configuration of Bardeen anisotropic spheres in modified f(G)gravity

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Communications in Theoretical Physics 2024年第6期76卷 45-56页

作者： Adnan malik Ayesha Almas Tayyaba Naz Rubab manzoor m z Bhatti School of mathematical Sciences Zhejiang Normal UniversityJinhuaZhejiangChina Department of mathematics University of Management and TechnologySialkot CampusLahorePakistan National University of Computer and Emerging Sciences Lahore CampusPakistan Department of mathematics University of Management and TechnologyJohar Town CampusLahore 54782Pakistan Department of mathematics University of the PunjabQuaid-i-Azam CampusLahore-54590Pakistan

The aim of this work is to investigate anisotropic compact objects within the framework of f(G)modified theory of *** our present work,we utilize Krori-Barua metrics,i.e.,λ(r)=Xr^(2)+Y andβ(r)=zr^(2).We use some matching conditions of spherically symmetric spacetime with Bardeen's model as an exterior ***,we establish some expressions of energy density and pressure components to analyze the stellar configuration of Bardeen compact stars by assuming viable f(G)*** examine the energy conditions for different stellar structures to verify the viability of our considered ***,we also investigate some other physical features,such as equilibrium condition,equation of state parameters,adiabatic index,stability analysis,mass function,surface redshift,and compactness factor,*** is worthwhile to mention here for the current study that our stellar structure in the background of Bardeen's model is more viable and stable.

关键词： Bardeen compact stars f(G)modified gravity Krori-Barua potential

RESEARCH ON LASER DIRECT DEPOSITION PROCESS OF Ti-6Al-4V ALLOY

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Acta metallurgica Sinica(English Letters) 2007年第3期20卷 171-180页

作者： S.Y. Gao Y.z. zhang L.K. Shi B.L. Du m.z. Xi H.z. Ji mechanical Engineering College Yanshan University O~mhuangdao 066004 China Beijing General Research Institute for Nonferrous metals Beijing 100088 China

Laser direct deposition （LDD） of metallic components is an advanced technology of combining CAD/CAm （computer aided design/computer aided manufacturing）, high power laser, and rapid prototyping. This technology uses laser beam to melt the powders fed coaxiaUy into the molten pool by the laser beam to fabricate fuUy dense metallic components. The present article mainly studies the LDD of Ti-6Al-4V alloy, which can be used to fabricate aircraft components. The mechanical properties of the Ti-6Al-4V alloy, fabricated by LDD, are obtained using the tension test, and the oxygen content of used powders and deposited specimens are measured. In the present article, it can be seen that the mechanical properties obtained using this method are higher than the ones obtained by casting, and equal to those got by wrought anneal. One aircraft part has been made using the LDD process. Because of this aircraft part, with sophisticated shape, the effect of the laser scanning track on the internal soundness of the deposited part was discussed.

关键词： laser direct deposition Ti-6Al-4V alloy mechanical property depositing process aircraft component

DAmPING BEHAVIOR OF ULTRAFINE-GRAINED PURE ALUmINUm L2 AND THE DAmPING mECHANISm

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Acta metallurgica Sinica(English Letters) 2006年第3期19卷 223-227页

作者： z.m. zhang C.J. Xu J.C. Wang H.z. Liu School of materials Science ＆ Engineering Xi＇an University of Technology Xi＇an 710048 Ghina State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi＇an 710072 Ghina

Ultrafine-grained pure aluminum L2 with a mean grain size of 1.01μm was produced by equal channel angular pressing （ECAP） and annealing at 150℃ for 2h. Damping behavior of the alloy was measured using a dynamic mechanical thermal analyzer. The alloy had an excellent damping capacity Q^-1 with the ambient value being 9.8×10^-3 at 1.0Hz when the strain amplitude was 2.0×10^-5. The damping behavior of the alloy showed a non-linear damping variation tendency, that is, with an increase in temperature and a decrease of frequency, the damping capacity of the alloy increased. The damping capacity increased with the strain amplitude when the strain amplitude was less than 4.6×10^-5. When the strain amplitude was higher than 4.6×10^-5, the damping capacity became a constant and independent of strain amplitude. The high damping capacity was attributed to dislocation unpinning and a drag of dislocation on pinning points.

关键词： ECAP ultrafine grain damping capacity aluminum alloy

Detonation initiation developing from the Richtmyer-meshkov instability

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Acta mechanica Sinica 2007年第4期23卷 343-349页

作者： H.H.Teng z.L.Jiang z.m.Hu LHD.Institute of mechanics,CAS.Beijing 100080,China LHD Institute of Mechanics CAS Beijing 100080 China

Detonation initiation resulting from the Richtmyer-meshkov instability is investigated numerically in the configuration of the shock/spark-induced-deflagration interaction in a combustive gas mixture. Two-dimensional multi-species Navier-Stokes equations implemented with the detailed chemical reaction model are solved with the dispersion-controlled dissipative scheme. Numerical results show that the spark can create a blast wave and ignite deflagrations. Then, the deflagration waves are enhanced due to the Richtmyer-meshkov instability, which provides detonation initiations with local environment conditions. By examining the deflagration fronts, two kinds of the initiation mechanisms are identified. One is referred to as the deflagration front acceleration with the help of the weak shock wave, occurring on the convex surfaces, and the other is the hot spot explosion deriving from the deflagration front focusing, occurring on the concave surfaces.

关键词： Hot spot Deflagration front acceleration Detonation initiation Richtmyer-meshkov instability