材料期刊网

An Anomalous Kerr Loop of LaBaMnO Thin Film

Bihui HOU , Qinlun XU , Shizhuo JI , Tianpei ZHANG and Peng PENG (Dept. of Physics , University of Science & Technology of China , Hefei 230026 , China) Changhe SHANG and Yinjun WANG (State Key Lab. of Magnetism , Institute of Physics , Chinese Academy of Science

材料科学技术（英文）

An anomalous Kerr loop was observed in an oriented LaBaMno film annealed in oxygen. Many tiny crystal columns were observed with scanning tunneling microscope and magnetic force microscope. The magnetic moment m in the column is perpendicular outward to the surface, which forms a surface phase with spin pinning state. This spin pinning results in the obvious asymmetrical Kerr loop of magneto-optical effect when the magnetic field is in the two opposite directions vertical to the surface.

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Optical Absorption Characterizations of Porous Al_2O_3Host/NiO Nanocomposites

Weili CAI , Chimei MO , Lan ZHANG , Yuanhong LI and Lianzeng YAO)(Dept. of Materials Science and Engineering , University of Science and Technology of China , Hefei 230026 , China)

材料科学技术（英文）

Porous Al2O3 host/NiO nanocomposites have been prepared by pyrolysis of Ni2(OH)2CO3 inthe nanostructured Al2O3 hosts. Diffuse reflection spectra in the wavelength range of 200 to800 nm were measured. Results show that (1) in each spectrum exist several absorption bandsof nano-NiO. With increasing the pyrolysis temperature from 550 to 1000℃, the numbers ofabsorption bands of NiO increase from 2 to 6 (P1-P6), (2) comparing with optical absorptionbands of single crystal NiO, for porous nanocomposites the P1, P2 and P4 present "blue shift"and the P3, P5 and P6 exhibit "red shift"; (3) when the pyrolysis temperature, Tp, is 550℃, theabsorption bands become so weak that only two bands (P1 and P6) can be observed and inverselywhen Tp=1000℃ all six absorption bands of NiO are strong, (4) for porous Al2O3/NiOnanocomposites prepared by pyrolysis at 1000℃ the PF+ caused by the F+ centers in theAl2O3 host moves towards the short wavelength at first with increasing the doping amount ofNiO from 5 to 50 wt pct and then shifts to the long wavelength with further increasing NiO. Inthis paper, the above phenomena and mechanism of the absorption bands of NiO are discussedin detail.

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Conceptual design of Hefei advanced light source

中国物理C

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Conceptual design of Hefei Advanced Light Source(HALS)injection system

中国物理C

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Controversy about the Origin of the Grain Boundary Internal Friction Peak and Its Clarification

T.S.Ke (Tingsui GE)(Lab. of Internal Friction and Defects in Solids , Institute of Solid State Physics , Chinese Academy of Sciences , Hefei 230031 , China)

材料科学技术（英文）

In the seventies some scientific workers from France and ltaly suggested that the grain boundary internal friction peak (named the Ke peak in the literature) widely accepted as a grain bound ary process, is originated from the motion of lattice dislocations. Since this problem is one of fundamental importance, this controversy has drawn much international attention. Started from 1982, the Hefei research group made a critical analysis of the large amount of literature concerning this problem and performed a series of crucial experiments to clarify the controversy It is concluded that the irrelevant evidence suggested by the controverters comes from the farfetched interpretation and the mis-identification of the internal friction peaks appeared under various experimental conditions and different states of the specimens.

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