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Science china Chemistry 2007年第4期50卷 468-475页

作者： WANG ZhengWu1 & YI XiZhang2 1 Department of Food Sciences & Technology, school of Agriculture and Biology, Shanghai Jiao Tong university, Shanghai 200240, china 2 Institute of Theoretical Chemistry, shandong university, jinan 250100, china 1. Department of Food Sciences & Technology School of Agriculture and Biology Shanghai Jiao Tong University Shanghai 200240 China 2. Institute of Theoretical Chemistry Shandong University Jinan 250100 China

By using the binary anionic/cationic surfactants system CH3(CH2)nOSO_3/CH3(CH2)nN+(CH3)3 as an ex-ample, the molecular exchanging energy (ε) of adsorption on the surface monolayer of aqueous solu-tion has been studied. ε can be obtained with two methods. One is from the relationship between ε and the molecule interaction parameter (β). This relationship is founded by considering that the adsorption of mixed surfactants on the surface monolayer of solution satisfies the dimensional crystal model condition under which β can be obtained by testing the surface tension of solution. The other is directly from the molecular structure of surfactants with the Lennard-Jones formula. The results for the studied system show that these two methods coincide well.

关键词： surfactant molecule exchanging energy dimensional crystal model

Morita contexts on the Hopf algebroid

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Science china Mathematics 2005年第7期48卷 958-971页

作者： YIN Yanmin school of Mathematical Sciences, Peking university, Beijing 100871, china Department of Mathematics, shandong Institute of Architecture and Engineering, jinan 250101, china 1. school of Mathematical Sciences Peking University 100871 Beijing China 2. Department of Mathematics Shandong Institute of Architecture and Engineering 250101 Jinan China

We generalize the Morita theory to the Hopf algebroid and give the characterization of the surjectivity of one of the Morita context maps.

关键词： comodule algebra, generalized smash product, Morita context.

Study on the cluster of floating dross before nucleating during hot-dipping process

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Science china Chemistry 2005年第1期48卷 83-88页

作者： WEI Yunhe1, ZHANG Changqiao1, QIN Jingyu2 & LIU Chengbu1 1. school of Chemistry and Chemical Engineering, shandong university, jinan 250100, china 2. The Key Laboratory of Liquid Structure and Heredity of Materials of Ministry of Education, shandong university, jinan 250061, china 1. school of Chemistry and Chemical Engineering Shandong University 250100 Jinan China 2. The Key Laboratory of Liquid Structure and Heredity of Materials of Ministry of Education Shandong University 250061 Jinan China

During hot-dipping in molten Zn-55Al, the forming of “floating” dross is closely re- lated with the interaction between the Al and the Fe atoms. Utilizing the thita-thita X-ray diffraction and the Percus-Yevick hard sphere model, this paper investigates the structure of molten Al3Fe that is an approximant of partial melt in practical Zn-55Al alloy melt. It is found that in the melt there exist clusters that resemble the structure of intermetallic compound Al3Fe. The strong in- teraction between Al and Fe atoms is also indicated by the deficiency of the coordination number from 12 and the shrinkage of averaged atomic diameter. Based on such information, it is specu- lated that in the molten Zn-55Al, with the accumulation of Fe, Al3Fe-like clusters form with priority, then grow into dross. On the other hand, after deflating of the effective hard sphere diameter of pure Al atom and enlarging that of the pure Fe atom, the modified model can achieve reasonable fit to the experimental structure factor. Hard sphere modeling also gave a good estimation of the mass density 3.65 g/cm3 of liquid Al3Fe alloy at 1550℃. Compared with the density of 3.7 g/cm3 of Zn-55Al, the reason for dross floating is satisfactorily understood.

关键词： hot-dipping, dross, Al3Fe alloy, molten structure, P-Y model.

Synthesis and structural characterization of Zn_3N_2 powder

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Science china(physics,Mechanics & Astronomy) 2005年第2期48卷 201-210页

作者： ZONG Fujian1, MA Honglei1, XUE Chengshan2, ZHUANG Huizhao2, ZHANG Xijian1, MA Jin1, JI Feng1 & XIAO Hongdi1 1. school of physics and Microelectronics, shandong university, jinan 250100, china 2. Institute of Semiconductor, shandong Normal university, jinan 250014, china school of physics and Microelectronics Shandong University Jinan 250100 China Institute of Semiconductor Shandong Normal University Jinan 250014 China

Zinc nitride (Zn3N2) powder has been synthesized through the nitridation reaction of Zn powder with NH3 gas (at the flow rate of 500 ml/min) at the nitridation temperature of 600℃ for 120 min. X-ray diffraction (XRD) indicates that Zn3N2 is cubic in structure with the lattice constant being a = 0.9788 nm. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show that Zn3N2 powder has surface morphology of various types. X-ray photoelectron spectroscopy (XPS) shows the differences in chemical bonding states between Zn3N2 and ZnO, and confirms the formation of N–Zn bonds. Observation through high resolution transmission electron microscopy (HRTEM) also indicates that the computer simulation of the structure of Zn3N2 is consistent with the structural model put forward by Partin.

关键词： nitridation, Zn3N2 powder, structure, XRD, SEM, TEM, HRTEM, XPS.

Lattice Effects and Irreversible Magnetoresistance in Gd Doped La-Ca-Mn-O

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Journal of Materials Science & Technology 2002年第6期18卷 509-512页

作者： Baoxin HUANG, Yihua LIU, Ruzhen ZHANG, Chengjian WANG, Gang JI and Liangmo MEIDepartment of physics and State Key Laboratory of Crystal Materials, shandong university, jinan, 250100, china shandong Univ Dept Phys Jinan 250100 Peoples R China shandong Univ State Key Lab Crystal Mat Jinan 250100 Peoples R China

The Gd substituting effects for La in La0.67Ca0.33MnO3 has been studied. With increasing the substituting amount of Gd, the phase transition temperature of metal-isolator for the samples decreases, the corresponding peak resistivity increases, the Curie temperature decreases monotonically. The substitution of La-Ca-Mn-O with 11% Gd for La improved the magnetoresistance ratio by an order of magnitude. The effects of substituting Gd can be explained in terms of the lattice effects. An irreversible MR behaviour was observed in Gd-substituting compounds. This effect became marked when the substituting amount of Gd was greater than 7%. A maximum irreversible increment of MR ratio as large as 91% was obtained when Gd substituting amount was 11%.

关键词： Manganese perovskites Colossal magnetoresistance Lattice effect Irreversible magnetoresistance

The optical near-field speckles and their first order statistics on the basis of the integral equations of electromagnetic field

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Science china(physics,Mechanics & Astronomy) 2004年第3期47卷 365-380页

作者： CHENG Chuanfu1, 2, SONG Hongsheng2, LIU Chunxiang2, REN Xiaorong2, ZHANG Ningyu3, TENG Shuyun1 & XU Zhizhan1 1. Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P. O. Box 800-211, Shanghai 201800, china 2. Department of physics, shandong Normal university, jinan 250014, china 3. shandong Institute of Architecture and Engineering, jinan 250014, china 1. Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences P. O. Box 800-211 201800 Shanghai China 2. Department of physics Shandong Normal University 250014 Jinan China 3. shandong Institute of Architecture and Engineering 250014 Jinan China

From Helmholtz equation of the harmonic electromagnetic waves, the integral equations of the light field at the medium boundaries are obtained by use of the Green's theorem and are discretized into linear equation set with the values of the light field and its derivative as the unknowns. On solving the linear equation set, we realize the rigorous computations of the light fields at the boundaries. Then the intensities of the light waves scattered by the random self-affine fractal surfaces in the optical near-field are calculated, and the propagation characteristics, the evolutions of the contrast and the intensity probability density function of the near-field speckles are studied in detail. The near-field speckles are much different from the conventional speckles in the diffraction regions and in the imaging systems. There are obvious local fluctuations in the intensity distributions of the near-field speckles and such fluctuations disappear after propagating a distance of one wavelength from the medium surfaces. For the random surfaces with smaller lateral correlation lengths, the speckle contrasts approach the saturation values and the speckle fields approach Gaussian distribution within the near-field, while for the random surfaces with larger lateral correlation lengths, such evolutions become comparatively slow.

关键词： speckle, near-field optics, first order statistics, Green's function.

Large deviation principle for diffusion processes under a sublinear expectation

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Science china Mathematics 2012年第11期55卷 2205-2216页

作者： CHEN ZengJing 1,2 & XIONG Jie 3,4,1 school of Mathematics,shandong university,jinan 250100,china 2 Department of Financial Engineering,Ajou university,Suwon 443749,Korea 3 Department of Mathematics,university of Macao,PO Box 3001,Macao,china 4 Department of Mathematics,university of Tennessee,Knoxville,TN 37996-1300,USA 1. school of Mathematics Shandong University Jinan 250100 China 2. Department of Financial Engineering Ajou University Suwon 443749 Korea 3. Department of Mathematics University of Macau PO Box 3001 Macau China 4. Department of Mathematics University of Tennessee Knoxville TN 37996-1300 USA

We represent the exponential moment of the Brownian functionals under a nonlinear expectation according to the solution to a backward stochastic differential *** an application,we establish a large deviation principle of the Freidlin and Wentzell type under the corresponding nonlinear probability for diffusion processes with a small diffusion coefficient.

关键词： large deviation principle backward stochastic differential equation g-expectation ambiguity

Magnetic properties and giant magnetoresistance effect of nanometer Fe-In_2O_3 granular films

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Chinese Science Bulletin 2002年第24期47卷 2025-2028页

作者： ZHANG Lin, LIU Yihua & HUANG BaoxinInstitute of physics and Microelectronics, shandong university, Ji’nan 250100, china Institute of physics and Microelectronics Shandong University Ji'nan China

Nanometer ferromagnetic metal-semiconductor matrix Fe-In2O3 granular films are fabricated by the radio frequency sputtering. Magnetic properties and the giant magnetoresistance (GMR) effect of Fex(In2O3)1-x granular film samples are studied. The result shows that the magnetoresistance (MR) ratio value of the granular film samples with Fe volume fraction x = 35% is 4.5% at room temperature. The temperature dependence (r = 1.5-300 K) of the MR ratio value of Fe0.35(In2O3)0.65 granular films shows that value below 10 K increases rapidly with the decrease of the temperature, and when T = 2 K, value is 85%. Through the study of the dependence of low field susceptibility on temperature and the hysteresis loops at different temperatures, it has been found that, when the temperature decreases to a critical point TP = 10 K, the change of the structure in Fe0.35(In2O3)0.65 granular films results in the transformation of state from ferromagnetic to spin-glass-like. The remarkable increase of the MR ratio value

关键词： granular films magnetic property giant magnetoresistance effect structure superparamagnetic.

INTERLAYER COUPLING AND FERROMAGNETIC RESONANCE IN Fe-Si/Cr MULTILAYERS

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Acta Metallurgica Sinica(English Letters) 1996年第4期9卷 283-286页

作者： S.S.Yan: YH Liu: X.D Ma,YM. Zhang and L.M Mei(Department of physics, shandong university, jinan 250100, china )

Fe-Si/Cr multilayers with amorphous Fe-Si magnetic layers and Cr nonmagnetic layers were prepared by an rf-sputtering *** the thickness of the Cr layers varies from 0.5 to 6 nm, the interlayer coupling oscillates periodically from ferromagnetic to antiferromagnetism. For each sample only one wide uniform resonance peak is detected by the ferromagnetic resonance. The uniform resonance field Hb and the resonance line width △H_b oscillate periodically as the thickness of the Cr layers increases, which is related to the oscillation of the interlayer coupling from ferromagnetic to *** oscillation period is about 1.5nm.

关键词： multilayer interlayer coupling ferromagnetic resonance

Fabrication and abrasive wear properties of metal matrix composites reinforced with three-dimensional network structure

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Rare Metals 2006年第6期25卷 671-679页

作者： WANG Shouren GENG Haoran LI Kunshan SONG Bo WANG Yingzi HUI Linhai school of Mechanical Engineering Jinan University Jinan 250022 China The Key Laboratory of Liquid Structure and Heredity of Materials Shandong University Jinan 250014 China school of Materials Science Jinan University Jinan 250022 China

Reticulated polyurethane was chosen as the preceramic material for preparing the porous preform using the replication process. The immersing and sintering processes were each performed twice for fabricating a high-porosity and super-strong skeleton. The aluminum magnesium matrix composites reinforced with three-dimensional network structure were prepared using the infiltration technique by pressure assisting and vacuum driving. Light interfacial reactions have played a profitable role in most of the ceramic-metal systems. The metal matrix composites interpenetrated with the ceramic phase have a higher wear resistance than the metal matrix phase. The volume fraction of ceramic reinforcement has a significant effect on the abrasive wear, and the wear rate can be decreased with the increase of the volume fraction of reinforcement.

关键词： metal matrix composites infiltration fficdon and wear three dimensional network structure microstructure