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EFFECT OF PROCESSING METHOD ON THE IMPACT STRENGTH OF POM/TPU/CaCO_3 TERNARY COMPOSITES

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Chinese Journal of Polymer science 2005年第5期23卷 531-537页

作者： Xiao-ling Gao Cheng Qu Qin Zhang Rong-ni Du and Qiang Fu department of Polymer science & materials,Sichuan university,State key laboratory of Polymer materials engineering,Chengdu 610065,china Sichuan Univ Dept Polymer Sci & Mat State Key Lab Polymer Mat Engn Chengdu 610065 Peoples R China

Polyoxymethylene （POM）/elastomer/filler ternary composites were prepared, in which thermoplastic polyurethane （TPU） and inorganic filler, namely, CaCO3, were used to achieve balanced mechanical properties of POM. The dispersion and phase morphology of POM/elastomer/filler composites were found to depend largely on processing method, CaCO3 content in masterbatch and the filler size. Two processing methods were employed to prepare POM/elastomer/filler ternary composites. One is called the one-step method, in which elastomer and the filler directly melt blended with POM matrix. The other is called the two-step method, in which the elastomer and the filler were mixed to get masterbatch first, which was then melt blended with pure POM of different content. The effect of phase morphology and processing method on impact strength was investigated. It was found that the two-step method results in an increase in impact strength but not for the one-step method. Additionally, the impact strength of POM ternary composites decreases with the increase in the size of CaCO3 particles.

关键词： POM/TPU/CaCO3 composites Core-shell structure Impact strength.

The Microstructure and Chemical Bonds of β-C_2S Under the High Energy Ball Grinding Function

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Journal of Wuhan university of Technology(materials science) 2006年第1期21卷 150-153页

作者：胡曙光 key laboratory for Silicate materials science and engineering of ministry of education Wuhan University of Technology Wuhan 430070 China

Using the laser granularity survey technology , logy, X-ray powder diffraction, scanning electron microscopy （SEM） and infrared spectrum anal）sis methods, we studied the microscopic structure and chemical bonds changes of β-C2 S monomineral under the high energy ball grinding function. The result indicates that, continuously under the mechanical power, β-C2 S crystal size would decrease, the micro strain and the effective Beff parameter would increase, and the amorphous phases would be presented. Furthermore, the mechanical power would cause Si-O bond broken and reorganized, the specific surface area would increase, the energy of micro-powder agglomeration vibration would be enhanced and the crystal would be disordered. Finally, β- C2 S was caused to have the mechanochemical change and the activity enhancement.

关键词： dicalcium silicate crystal microscopic structure mechanochemistry

Study on soil solidification based on microbiological precipitation of CaCO_3

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science china(Technological sciences) 2010年第9期53卷 2372-2377页

作者： LU WangJie,QIAN ChunXiang & WANG RuiXing School of materials science & engineering,Jiangsu key laboratory for Construction materials,Southeast university,Nanjing 210089,china 1. School of materials science & engineering Jiangsu Key Laboratory for Construction Materials Southeast University Nanjing 210089 China

The soil solidifying technology started booming from the 1940s and formed an integrated *** paper aimed to study the effect and mechanism of soil solidification by *** specimens treated by different methods were *** the compressive strengths of these specimens on day 7 were tested and the situ bacteria culturing technique in soil was *** the mechanism of soil solidification by microorganisms was explored according to the decomposition rate of substrate,pH value and the SEM and XRD *** results showed that the soil could be solidified by filling enhancement and precipitation of *** compressive strength increased with bacteria A but decreased with substrate B,and soil specimen got a higher strength with bacteria situ *** suitable pH value for bacteria A was 8–9,and the delay of lime addition could make substrate decomposition more completely,lower the influence by the existence of substrate,and improve the *** XRD and SEM images,precipitation of CaCO3 could be speculated.

关键词： soil solidification bacteria compressive strength situ cultured decomposition rate precipitation

Preparation and Properties of Dip-coated CeO_2-TiO_2 Thin Golden Glass Film

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Journal of Wuhan university of Technology(materials science) 2007年第3期22卷 482-485页

作者：李宏 key laboratory of Silicate materials science and engineering (Wuhan university of Technology) Ministry of Education

The golden and ultraviolet-absorbed CeO2-TiO2 film was prepared on soda-lime glass substrate with the thickness of 2 mm via the sol-gel method. The transmission spectra in range of 200 nm-800 nm were measured, and the crystallization, the abrasion and acid resistance were also investigated. The appropriate sol contents and heat-treatment schedule were determined. The results indicate that the appropriate molar ratio of Ce/Ti was 3：5 to 5：6. The ultraviolet-absorbance ability increased with the increase of the Ce/Ti molar ratio, but when the Ce/Ti molar ratio was higher than 1.5, the homogeneity of the film was deteriorated. With the increase of heat-treatment temperature, the main wavelengths of the color of the coated glasses were equal, but the color＇ s saturation decreased; the transmission peaks were the same, while the intensity of the peaks decreased. The roughness, abrasion and acid resistance of the film were also enhanced at the same time. The appropriate heat- treatment temperature may be 340℃.

关键词： sol-gel method CeO2-TiO2 film dip-coating process

Characterization of γ′ precipitates in a nickel base superalloy quenching from aging temperature at different rates

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Rare Metals 2010年第2期29卷 204-208页

作者： LI Hongyu, SONG Xiping, WANG Yanli, and CHEN Guoliang State key Lab for advanced Metals and materials, university of science and Technology beijing, beijing 100083, china State key Lab for advanced Metals and materials University of Science and Technology Beijing

The characteristics of γ′ precipitates in a superalloy quenched from 1050°C at different rates were investigated using field emission scanning electron microscope（FESEM）.When quenched from 1050°C, the size of primary aging γ′ precipitates has a small increase in the specimens that experienced iced-brine-quenching, oil-quenching, and air-cooling-quenching conditions and a drastic increase in the specimen that experienced a furnace-cooling-quenching *** cooling γ′ precipitates have unimodal distributions after quenching at the air-cooling rate and bimodal distributions after quenching at the furnace-cooling rate, but there are not these distributions in the specimens that experienced iced-brine-quenching and oil-quenching *** aging at 760°C, the size of primary aging γ′ precipitates appears unaffected in the specimens that experienced iced-brine-quenching, oil-quenching, and air-cooling-quenching ***, it has a drastic increase in the specimen that experienced a furnace-cooling-quenching condition, and it is interesting that the bigger cooling γ′ precipitates have a coalescence and octodendritic *** microhardness study indicates that the hardness has no variation in the specimens that experienced iced-brine-quenching, oil-quenching, and air-cooling-quenching conditions and has a drastic decrease in the specimens that experienced a furnace-cooling-quenching condition and obtains the minimum microhardness value 390.8 HV.

关键词： superalloys precipitates quenching rate microhardness

UV Spectral Analysis of the Chemical Modification and Photolysis of Acetylacetone Modified Alumina Aqueous Solution

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Journal of materials science & Technology 2004年第5期20卷 639-640页

作者： Chengbin JING, Xiujian ZHAO, Haizheng TAO, Xina WANG and Aiyun LIUkey laboratory of Silicate materials science and engineering, ministry of education, Wuhan university of Technology, Wuhan 430070, china Lab. of Silicate Mat. Sci. and Eng. Wuhan Univ. of Technol. Wuhan 430070 China

Acetylacetone was firstly introduced into the aqueous media with the presence of aluminum sec-butoxide and pep-tizator. It was confirmed that the UV (ultraviolet) absorption band of acetylacetone underwent 14 nm of red-shift due to the formation of the six-membered ring of the complex between alumina and acetylacetone in the aqueous solution. It was also found that the chemical modification can be dissociated by the UV irradiation with a wavelength shorter than 286 nm as a result of the excitation of π-π* transition in the complex.

关键词： Chemical modification Aluminum sec-butoxide Acetylacetone Photolysis

LARGE DEFLECTION THEORY OF NANOBEAMS

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Acta Mechanica Solida Sinica 2010年第5期23卷 394-399页

作者： Dujuan Zeng Quanshui Zheng 1(department of engineering Mechanics,tsinghua university,beijing 100084,china) [a] department of engineering Mechanics Tsinghua University Beijing 100084 China

One-dimensional nanostructured materials are often used as beams in many applications such as ultrahigh-frequency resonators and ultrasensitive sensors. Compared with usual macroscopic beams, nanobeams have much higher surface/volume ratios so that their surface energies may play a significant role. Besides, they often bear large deflections due to their typically large slenderness ratios and larger elastic ranges. There is, however, lack of a theory that takes into account of both the above two features owned by nanobeams. In this paper, we present such a theory and give applied examples to show that surface energy and large deflection may individually or jointly have notable effects.

关键词： nanobeam surface energy large deflection

Localization of calmodulin and calmodulin-like protein and their functions in biomineralization in P. fucata

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Progress in Natural science:materials International 2008年第4期18卷 405-412页

作者： Zi Fang a, Zhenguang Yan a, Shuo Li a, Qin Wang a, Weizhong Cao a, Guangrui Xu a, Xunhao Xiong a, Liping Xie a,b, Rongqing Zhang a,b, a Institute of Marine Biotechnology, department of Biological science and Biotechnology, tsinghua university, beijing 100084, china b Protein science laboratory of the ministry of education, tsinghua university, beijing 100084, china Institute of Marine Biotechnology Department of Biological Science and Biotechnology Tsinghua University Beijing 100084 China Protein science laboratory of the ministry of education Tsinghua University Beijing 100084 China

Calmodulin (CaM) and calmodulin-like protein (CaLP) are two proteins involved in biomineralization. Their localizations in Pinct- ada fucata mantle epithelia were studied by Western blot (WB) analysis of the nuclear/cytosol fraction of primary cultured P. fucata mantle cells and immunogold electron microscopy. The results showed a completely different distribution of these two proteins at the subcellular level. CaM was distributed throughout both the nucleus and cytoplasm of the mantle epithelium but CaLP was distributed only in the cytoplasm. The functions of these two proteins in biomineralization were investigated by shell regeneration. During this pro- cess, the expressions of CaM and CaLP were greatly enhanced in different organelles of the mantle epithelium. Overexpression of these two proteins and a mutant of calmodulin-like protein (M-CaLP) that lacks an extra C-terminal tail in MC3T3-E1 promoted the mRNA expression of osteopontin, a biomineralization marker for osteoblasts. All of the results indicated that CaM and CaLP have completely different distributions in the mantle epithelium and affect the biomineralization process at different levels. The extra C-terminal tail of CaLP is important for its functions in biomineralization in P. fucata.

关键词： Pinctada fucata Calmodulin Calmodulin-like protein Immunogold electron microscopy

Analysis on Microstructure and Misorientation of Ultrathin Hot Strip of Low Carbon Steel Produced by Compact Strip Production

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Journal of materials science & Technology 2002年第6期18卷 501-503页

作者： Hao YU, Yonglin KANG and Jie FUSchool of materials science and engineering, university of science and Technology beijing, beijing 100083, china Sch. of Mat. Sci. and Eng. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The microstructure and misorientation of ultrathin hot strip were analyzed by CSP technology using electron back scattered diffraction (EBSD) method and Autoforge finite element program. The experimental results showed that the finishing hot rolling microstructures were the mixture of recrystallized and deformed austenite. After phase transformation, ferrite grains embody substructures and dislocations, leading to the high strength and relatively low elongation rate of the ultrathin hot strip. The FEM simulation of strain mode and distribution in deformation area has been fulfilled. The simulation results are in good agreement with the theoretical analysis and experimental results.

关键词： CSP Electron back scattered diffraction, Texture, Finite element method