xBST-(1-x)YIG composite ceramics with x=0-1 were prepared by solid-state reaction method. The variations for phase compositions were determined by XRD, and the magnetic and dielectric properties of the composites were...
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xBST-(1-x)YIG composite ceramics with x=0-1 were prepared by solid-state reaction method. The variations for phase compositions were determined by XRD, and the magnetic and dielectric properties of the composites were studied in the frequency range of 100Hz-1GHz. The results showed that the composites (x=0.1-0.9) are consisted of BST phase and YIG phase and no significant chemical interaction occurs between these two phases. The composite materials exhibit excellent frequency dependences of dielectric and magnetic properties. The resonance frequency and high frequency characteristics of YIG are improved by additions of BST, and when x=0.3, xBST-(1-x)YIG has the best dielectric and magnetic properties.
Three series of ZnO-based materials with different doping levels were prepared. The correlation between the composition and microstructure, and the roles of main dopants, Bi2O3 and Sb2O 3, in the sintering behaviors w...
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Three series of ZnO-based materials with different doping levels were prepared. The correlation between the composition and microstructure, and the roles of main dopants, Bi2O3 and Sb2O 3, in the sintering behaviors were proposed. Both Bi 2O3 and Sb2O3 evaporated at 1115°C, but the amount of them, in which bismuth is the majority, is not significant. Bi2O3 functioned mainly as liquid during sintering to promote the sintering of ZnO, but it doesn't mean the materials will be denser. The bismuth-rich phase retracted into small pores during cooling, leaving the big pores as voids at room temperature. More Bi 2O3 added would result in less increase in material densities and dramatic decrease in relative densities, and a little bit increase in grain sizes of matrix ZnO. Sb2O3 would react with ZnO matrix into spinel, Zn7Sb2O12, which will pin at the grain boundary of ZnO to control the ZnO grain growth. The more Sb 2O3 added, the smaller the grain sizes of ZnO. Appropriate amount of Sb2O3 added will yield denser materials.
Lotus fiber,which is isolated from the secondary wall of tracheary elements in lotus petiole,is a new kind of natural fiber with high quality and great developing *** fabric made of it has good moisture absorption and...
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Lotus fiber,which is isolated from the secondary wall of tracheary elements in lotus petiole,is a new kind of natural fiber with high quality and great developing *** fabric made of it has good moisture absorption and permeability,fine flexibility and elasticity,antistatic property *** structural and morphological analysis of lotus fiber and lotus petiole is carried out using optical microscope,SEM,and *** properties and decomposition mechanism of lotus fiber have been determined by TG and DSC analyses in comparison to *** studies on structure and properties of lotus fiber can lay a foundation for comprehensive development and utilization of this fiber.
In this paper,the ultrasound alone and microwave-ultrasonic treatment were used to obtain the Apocynum venetum *** structures and properties of fibers obtained by above mentioned methods were characterized by scanning...
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In this paper,the ultrasound alone and microwave-ultrasonic treatment were used to obtain the Apocynum venetum *** structures and properties of fibers obtained by above mentioned methods were characterized by scanning electron microscopy(SEM),transform infrared(FTIR) spectroscopy and mechanical property by *** was found that the fibers treated by ultrasound and microwaveultrasound were the structure of cellulose Ⅰ as well as the bast of Apocynum venetum according to ***,seen from SEM micrographs,the fibers treated by microwave-ultrasound were cleaner than that of fibers treated by ***,the mechanical property of fibers treated by two methods confirmed the fibers were suitable for textile *** results suggested that ultrasonic and microwave-ultrasonic pretreatment were higher efficiency and more environmental friendly than traditional chemical degumming methods.
CaCu3Ti4O12 (CCTO) ceramic thick films have been prepared on Copper substrate, using ceramic powders by an aerosol deposition method (ADM). The ceramic powders are prepared by traditional solid state reaction processi...
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CaCu3Ti4O12 (CCTO) ceramic thick films have been prepared on Copper substrate, using ceramic powders by an aerosol deposition method (ADM). The ceramic powders are prepared by traditional solid state reaction processing at 1100°C for 5 h. X-ray diffraction and scanning electron microscopy are used to investigate the microstructure and the phase composition of the deposited films. The results indicate that thick films are pure CCTO phase and homogenous. The dielectric impedance spectra indicate that the dielectric constant of CCTO thick film can reach 3×103.
A new compound,[Co（dien）2]（dienH3）（H3O）7[P2Mo5O23]2·14H2O, has been hydrothermallly synthesized by using Na2MoO4,CoCl2, H3PO4 and dien, and structurally characterized by elemental analysis, X-ray powder dif...
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A new compound,[Co（dien）2]（dienH3）（H3O）7[P2Mo5O23]2·14H2O, has been hydrothermallly synthesized by using Na2MoO4,CoCl2, H3PO4 and dien, and structurally characterized by elemental analysis, X-ray powder diffraction analysis, SEM, IR and TG analysis. The results show that the compound is composed of a polyanion [P2Mo5O23]2^12, complex [Co（dien）2]^2＋ cation, protonated [dienH3]^3＋ , and forteen crystallization water molecule.
An intrinsic plastic Cu45Zr46Al7Ti2 bulk metallic glass (BMG) with high strength and superior compressive plastic strain of up to 32.5% was successfully fabricated by copper mold casting. The superior compressive plas...
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An intrinsic plastic Cu45Zr46Al7Ti2 bulk metallic glass (BMG) with high strength and superior compressive plastic strain of up to 32.5% was successfully fabricated by copper mold casting. The superior compressive plastic strain was attributed to a large amount of randomly distributed free volume induced by Ti minor alloying, which results in extensive shear band formation, branching, interaction and self-healing of minor cracks. The mechanism of plasticity presented here suggests that the creation of a large amount of free volume in BMGs by minor alloying or other methods might be a promising new way to enhance the plasticity of BMGs.
We report the magnetic properties of slightly electron-doped Sm1−xCaxMnO3 (0.80≤x≤0.92). The Griffiths phase behavior in the inverse magnetic susceptibility was observed for x≥0.85. The thermomagnetic irreversibili...
We report the magnetic properties of slightly electron-doped Sm1−xCaxMnO3 (0.80≤x≤0.92). The Griffiths phase behavior in the inverse magnetic susceptibility was observed for x≥0.85. The thermomagnetic irreversibility found in all samples could be explained according to the influence of martensitic strain on the magnetization behavior under various cooling histories. In the modified phase diagram, the low-field thermomagnetic irreversibility line passes through the region of Griffiths phase, indicating that the Griffiths phase is correlated with the accommodation strain. Our result indicates that the strain field, in addition to quenched disorders, may be an alternative approach to understand the observed Griffiths phase. Besides, the Griffiths phase itself is suggested to be insufficient for the appearance of colossal magnetoresistance effect in the present system.
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