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SYNTHESIS AND CHARACTERIZATION OF POLY(PHTHALAZINONE BIPHENYL ETHER SULFONE KETONE)S FROM 4,4'-DICHLOROBENZOPHENONE

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Chinese Journal of Polymer Science 2011年第6期29卷 719-725页

作者：刘程蹇锡高 Department of Polymer Science and Materials College of Chemical EngineeringDalian University of Technology Liaoning Province engineering Center of High Performance Resins

A series ofpoly（aryl ether sulfone ketone）s containing phthalazinone and biphenyl moieties were synthesized by aromatic nucleophilic displacement polycondensation of 4-（4-hydroxylphenyl）（2H）-phthalazin-l-one （DHPZ）, 4,4＇- dichlorobenzophenone （DCB）, 4,4＇-dichlorodiphenyl sulfone （DCS） and 4,4＇-biphenol （BP） in different molar ratios. The obtained copolymers were characterized by different instrumental techniques （FTIR, TGA, DSC, WAXD, etc.）. The inherent viscosities of these polymers were in the range of 0.43-0.56 dL g^-1. They were amorphous and had good solubility in polar aprotic organic solvents. The copolymers exhibited high glass transition temperatures （TgS） between 225℃ and 256℃and excellent thermal stability up to 51.-526℃ （thermal decomposition temperatures for 5% weight loss, Td, 5%） in nitrogen. The tensile strength and elongation at break of the polymers ranged from 63 MPa to 71.MPa and from 1.% to 21., respectively. The processability of the material was effectively improved by the introduction of biphenyl group into polymer backbone.

关键词： Phthalazinone Poly(aryl ether) Polycondensation Processability Thermal stability

Properties and Applications of the Eccentric-gear Drive

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Chinese Journal of Mechanical engineering 2011年第2期24卷 323-331页

作者： ZHAO Yun SUN Liang YU Gaohong college of Mechanical {1. and Automation Zhejiang Sci-Tech UniversiO Hangzhou 31.01. China

The eccentric-gear can be used for variable speed ***,due to the vibrations caused by variation of backlash in working process,the eccentric-gear is seldom applied in engineering *** is just a little study about the *** it is necessary to take a further research on eccentric-gear transmission for the applications in the transplanting mechanism of high-speed rice *** key of this paper is to extend understanding of three following characteristics of this drive：（1. The rotation-center-distance and the geometrical-center-distance of the two meshing eccentric gears are respectively the hypotenuse and the straight edge of a right triangle in a cycle.（2） The geometrical center line of two meshing gears divides the linking-line of the two rotational centers equally.（3） When two times the eccentricity of gear,the rotation-center-distance and the geometrical-center-distance form a right triangle,the optimal value of rotation-center-distance can be *** addition,the kinematic analysis,such as the relationship between contact point and midpoint of the linking-line of two gears＇ rotational centers,transmission ratio between the driving-gear and the driven-gear,contact angle and coordinate of contact point are be made,further the formula for calculation of contact force,flow chart for writing optimization program and curve for analysis of data are also be *** relationship between the rotation-center-distance and the geometrical-center-distance,which is determined by three characteristics mentioned above, is a key for the rational design and application of eccentric-gear ***,the presented right triangle property of eccentric gear drive is an important reference for effective analysis of dynamic characteristic of eccentric-gear mechanism and its reliable design.

关键词： eccentric gear transmission property variable speed transmission kinematic and dynamic analysis

Synthesis and Characterization of Mesoporous Alumina via a Reverse Precipitation Method

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Journal of Materials Science & Technology 2012年第6期28卷 572-576页

作者： Y.S.Wu J.Ma F.Hu M.C.Li college of Materials Science and {1. Shenyang University of TechnologyShenyang 110870China

Mesoporous aluminaΥ-AI203 with high specific surface area and large pore volume is prepared by using a facile reverse precipitation method from sodium aluminate and nitric acid. The effects of terminal pH value, aging time and thermal stability on the characterization of Υ-Al2Oa are studied by means of X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR）, Brunauer-Emmett-Teller （BET） method and scanning electron microscopy （SEM）. The results show that Υ-A1.03 with better properties can be obtained by changing the preparation parameters. High BET surface area of 340 m2/g can be obtained by calcining at 500℃ for 4 h with large pore volume of 0.90 cm3/g and average pore size of 7.6 nm. After calcining at 1.00°, the surface area is still 86 m2//g and the pore volume is 0.37 cm31.g.

关键词： Mesoporous alumina Reverse precipitation Thermal stability

Study on coupled vibration characteristics of a cylindrical container with multiple elastic annular baffles

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Science China(Technological Sciences) 2012年第12期55卷 3292-3301页

作者： WANG JiaDong ZHOU Ding LIU WeiQing college of Civil {1. Nanjing University of TechnologyNanjing 210009China

The coupled vibration characteristics of multiple elastic annular baffles of the same inner radius in a partially liquid-filled rigid cylindrical container were studied. The liquid domain was divided into several simple sub-domains so that the liquid velocity potential in each liquid sub-domain was of class C 1.with continuous boundary conditions. Based on the superposition principle, the general solution of the liquid velocity potential corresponding to each liquid sub-domain was obtained by means of the method of separation of variables. The coupled modes of the multiple elastic annular baffles were expressed in terms of dry-modal functions. The free surface condition, the interface conditions and coupled vibration conditions were expressed in terms of Fourier series along the liquid height and Bessel series in the radial direction, respectively. Stable and fast numerical computations were investigated by the convergence study. Excellent agreements have been achieved in the comparison of re- suits obtained by the proposed approach with those given by the finite element software ADINA. The natural frequencies and mode shapes versus the position, the inner radius and the number of the annular baffles were thoroughly discussed.

关键词： liquid-container interaction sub-domains multiple baffles sloshing mode bulging mode

In Vitro Evaluation of the Feasibility of Commercial Zn Alloys as Biodegradable Metals

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Journal of Materials Science & Technology 2016年第9期32卷 909-918页

作者： C.Wang H.T.Yang X.Li Y.F.Zheng Department of Interventional Radiology and Vascular Surgery Peking University Third Hospital Department of Materials Science and engineering College of Engineering Peking University

In this work, three widely used commercial Zn alloys （ZA4-1. ZA4-3, ZA6-1.） were purchased and pre- pared by hot extrusion at 200℃. The microstructure, mechanical properties, corrosion behaviors, biocompatibility and hemocompatibility of Zn alloys were studied with pure Zn as control, Commercial Zn alloys demonstrated increased strength and superb elongation compared with pure Zn. Accelerated corrosion rates and uniform corrosion morphologies were observed in terms of commercial Zn alloys due to galvanic effects between Zn matrix and α-Al phases. 1.0% extracts of ZA4-1.and ZA6-1.alloys showed mild cytotoxicity while 50% extracts of all samples displayed good biocompatibility. Retardant cell cycle and inhibited stress fibers expression were observed induced by high concentration of Zn^2＋ releasing during corrosion. The hemolysis ratios of Zn alloys were lower than 1. while the adhered platelets showed slightly activated morphologies. In general, commercial Zn alloys possess promising mechanical properties, appropriate corrosion rates, significantly improved biocompatibility and good hemocompatibility in comparison to pure Zn. It is feasible to develop biodegradable metals based on commercial Zn alloys.

关键词： Commercial Zn alloys Biodegradable metals Mechanical properties Corrosion behaviors Cytotoxicity Hemocompatibility

Synthesis and application of bilayer-surfactant-enveloped Fe_3O_4 nanoparticles: water-based bilayer-surfactant-enveloped ferrofluids

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International Journal of Minerals,Metallurgy and Materials 2016年第2期23卷 234-240页

作者： Bai-yi Chen Jian-hui Qiu Hui-xia Feng Department of Machine Intelligence and Systems engineering Faculty of Systems Engineering Akita Prefectural University college of Petrochemical Technology Lanzhou University of Technology

Superparamagnetic carbon-coated Fe3O4 nanoparticles with high magnetization（85 emu·g-（-1.） and high crystallinity were synthesized using polyethylene glycol-4000（PEG（4000）） as a carbon ***3O4 water-based bilayer-surfactant-enveloped ferrofluids were subsequently prepared using sodium oleate and PEG（4000） as *** using X-ray photoelectron spectroscopy,X-ray diffraction,and Fourier-transform infrared spectroscopy indicate that the Fe3O4 nanoparticles with a bilayer surfactant coating retain the inverse spinel-type structure and are successfully coated with sodium oleate and PEG（4000）.Transmission electron microscopy,vibrating sample magnetometry,and particle-size analysis results indicate that the coated Fe3O4 nanoparticles also retain the good saturation magnetization of Fe3O4（79.6 emu·g^-1. and that the particle size of the bilayer-surfactant-enveloped Fe3O4 nanoparticles is 42.97 nm,which is substantially smaller than that of the unmodified Fe3O4 nanoparticles（486.2 nm）.UV-vis and zeta-potential analyses reveal that the ferrofluids does not agglomerate for 1.0 h at a concentration of 4 g·L^-1.which indicates that the ferrofluids are highly stable.

关键词： magnetic fluids iron oxides nanoparticles bilayers sodium oleate polyethylene glycol

A hybrid deterministic-stochastic model for spouted beds

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Particuology 2019年第1期17卷 104-113页

作者： Shahab Golshan Reza Zarghami Navid Mostoufi Process Design and Simulation Research Centre. School of Chemical engineering. {1. of engineering University of Tehran. TehranIran

A new hybrid deterministic-stochastic model is developed and used to simulate a slot-rectangular spouted *** model includes deterministic and stochastic steps that are executed in *** simulation starts with the deterministic part of the model,in which the computational fluid dynamics-discrete element method (CFD-DEM) equations are solved for 1.s to give the initial velocity distribution of the *** stochastic part is then executed,with the hydrodynamics of the bed taken from the velocity distributions acquired in the first step through Monte Carlo sampling.A full deterministic (CFD-DEM) simulation of the bed is also conducted for comparison with the proposed hybrid ***,the proposed hybrid is validated using experimental data from the *** validations are based on the axial and lateral velocity distributions of the particles and the bed *** effects of the cell size and number of sampling steps on the accuracy of the model are also *** performance of the proposed model is compared with the CFD-DEM results in terms of the computation time and the rate of solid circulation in the *** hybrid model is found to have shorter runtimes than the CFD-DEM approach.

关键词： CFD–DEM Monte Carlo Spouted bed Hydrodynamics Solid circulation rate

Corrosion behavior of magnesium and magnesium alloys

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中国有色金属学会会刊：英文版 2004年第1期14卷 1-10页

作者： I.M.Baghni 吴荫顺李久青张巍 Mechanical engineering Department Engineering College Tajoura Libya Corrosion & Protection Center University of Science and Technology Beijing Beijing 100083 China

The automotive industry has crossed the threshold from using magnesium alloys in interior applications such as instrument panels and steering wheels to unprotected environment such as oil pan, cylinder head and wheels. The expanding territory of magnesium leads to new challenges: mainly environmental degradation of the alloys used and how they can be protected. The present critical review is aimed at understanding the corrosion behavior of magnesium and magnesium alloys in industrial and marine environments, and the effect of microstructure, additive elements and inhibitors on the corrosion mechanism.

关键词：镁镁合金腐蚀显微结构汽车工业

Effect of Potassium and C/N Ratios on Conversion of NH_4^+ in Soils

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Pedosphere 2008年第4期18卷 539-544页

作者： TANG Yan WANG Xiao-Zhi ZHAO Hai-Tao FENG Ke college of Environment Science and {1. Yangzhou University Yangzhou 225009 （China）

Two soils, one consisting of 1.1.clay minerals at pH 4.5 and the other containing 2:1.clay minerals at pH 7.0, were used to estimate the conversion of added NH+4 under different C/N ratios (glucose as the C source) and the addition of potassium. Under lower C/N ratios (0:1.and 5:1., a large part of the added NH4+ in the acid soil was held in the forms of either exchangeable or water soluble NH4+ for a relatively long time and under higher C/N ratio (50:1., a large amount of the added NH4+ was directly immobilized by microorganisms. In the second soil containing appreciable 2:1.type clay minerals a large part of the added NH+4 at first quickly entered the interlayer of the minerals under both lower and higher C/N ratios. In second condition, however, owing to microbial assimilation stimulated by glucose the newly fixed NH4+c ould be completely released in further incubation because of a large concentration gradient between external NH4+ and fixed NH4+ in the mineral interlayer caused by heterotrophic microorganisms, which imply the fixed NH4+ to be available to plants. The results also showed that if a large amount of K+ with carbon source together was added to soil, the higher K+ concentration of soil solution could impede the release of fixed NH4+ , even if there was a lot of carbon source.

关键词： clay minerals fixed NH4^+ N mineralization organic C potassium