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941.
Controllable Preparation of Al2O3‐MgO·Al2O3‐CaO·6Al2O3 (AMC) Composite with Improved Slag Penetration Resistance 下载免费PDF全文
Junhong Chen Mingwei Yan Jindong Su Bin Li Kuo‐Chih Chou Xinmei Hou Mao Chen Baojun Zhao 《International Journal of Applied Ceramic Technology》2016,13(1):33-40
Compact Al2O3‐MgO·Al2O3‐CaO·6Al2O3 (AMC) composite was obtained by melting technology using industrial alumina, light‐burned magnesia, and quick lime as raw materials based on the Al2O3‐MgO‐CaO ternary phase diagram. The results show that the phases of MgO·Al2O3 and Al2O3 are formed as the main framework with plate‐like CaO·6Al2O3 crystals mainly discontinuously embedded in MgO·Al2O3. The bulk density of AMC composite is up to 3.42 g/cm3, equivalent to 90.5% of the theoretical density. The synthesized compact AMC composite in the work also exhibits better slag penetration resistance than the castable based on tabular corundum due to the formation of liquid phase. 相似文献
942.
The Relationship between Microstructure and Properties in PP/Rubber Powder/nano‐CaCO3 Ternary Blends
Xinqing Su Youqing Hua Jinliang Qiao Yiqun Liu Xiaohong Zhang Jianming Gao Zhihai Song Fan Huang Manli Zhang 《大分子材料与工程》2004,289(3):275-280
Summary: A new kind of rubber powder with “salami” structure (RPS) was prepared by spray drying the mixture of styrene‐butadiene rubber latex and nano‐CaCO3 slurry. It was found that RPS is an effective toughener with synergistic toughening effect on poly(propylene) (PP). The Izod impact strength of PP/RPS blend is not only higher than that of PP/rubber powder or PP/nano‐CaCO3 blends, but also higher than that of a PP/rubber powder/CaCO3 blend. TEM images show that the microstructure of the PP/RPS blend is an “island‐sea” structure with “salami” structure in RPS, in which nano‐CaCO3 particles are embedded in styrene‐butadiene rubber particles. The relationship between properties and microstructure has been studied by using TEM, SEM, DSC, etc.
943.
S. J. Liao W. H. Hsieh James T. Wang Y. C. Su 《Polymer Engineering and Science》2004,44(11):2029-2040
This study demonstrates the successful use of back‐propagation artificial neural networks (BPANNs) in predicting the shrinkage and warpage of injection‐molded thin‐wall parts. The effects of structural parameters of a BPANN on the predictionaccuracy and the capability of a BPANN in determining the optimal process condition are also discussed. The training and testing data are obtained experimentally based on a Taguchi L27 (313) test schedule. The results show that the trained BPANN can successfully predict the shrinkage and warpage of injection‐molded thin‐wall parts. Comparing the prediction accuracies of the trained BPANN and C‐Mold software, it is noted that the trained BPANN predicts more accurately. In terms of determining the optimal process condition for minimizing the shrinkage and warpage of injected thin‐wall parts, the trained BPANN is also shown to give a better optimal process condition than Taguchi's method. Polym. Eng. Sci. 44:2029–2040, 2004. © 2004 Society of Plastics Engineers. 相似文献
944.
Vinylbenzyl chloride was allowed to react with a low‐molecular‐weight oligomer of butadiene in order to give a material that could then be used to alkylate an amine to form an ammonium salt. This ammonium salt was ion‐exchanged onto a clay to give a new organically modified clay, which was used to prepare polystyrene‐clay nanocomposites by solution and bulk polymerization and by melt blending. The nanocomposites were characterized by using X‐ray diffraction, transmission electron microscopy, thermogravimetric analysis, cone calorimetry, and the evaluation of mechanical properties. These systems show good nanodispersion and improvement in thermal and mechanical properties. J. Vinyl Addit. Technol. 10:44–51, 2004. © 2004 Society of Plastics Engineers. 相似文献
945.
946.
Zhou‐Su Xu Cheng Xu Qiang‐Bing guo Xiao‐Feng Liu Jian‐Rong Qiu 《Journal of the American Ceramic Society》2016,99(3):760-764
Bi‐doped xTeO2–(60?x)GeO2–15B2O3–20MgO–5Al2O3 glasses were prepared by the conventional melt‐quenching method and their absorption and fluorescence spectra were characterized. Broadband near‐infrared (NIR) emission from Bi centers centered around 1240 nm with a full width at half maximum (FWHM) of 250 nm was observed, and the position of the emission peak strongly depends on the excitation wavelength. Increasing TeO2 concentration results in the strong coloration of the glass, leading to the reduction and finally, complete quenching of the NIR emission. Based on Raman, X‐ray photoelectron spectroscopy and transmission microscopy observation, the coloration of the glass at high TeO2 concentration can be ascribed to the precipitation of elemental Te nanoparticles of around 3–8 nm, which effectively suppresses the NIR emission by reabsorption. The precipitation of Te nanoparticles in an oxide glass may find novel applications in photonics and relevant fields. 相似文献
947.
Photopolymerizable multifunctional monomers and their evaluation as reactive Bis‐GMA eluents 下载免费PDF全文
J. Abraham González‐López Carlos E. Cuevas‐Suárez Alma Antonia Pérez‐Mondragón M. Lydia Berlanga Duarte Ana M. Herrera‐González 《应用聚合物科学杂志》2018,135(19)
Bis‐GMA {2,2‐bis[4‐(2′‐hydroxy‐3′‐methacryloyloxy‐propoxy)‐phenyl]‐propane}, TEGDMA <2‐{2‐[2‐(2‐methylprop‐2‐enoyloxy)ethoxy]ethoxy}ethyl‐2‐methylprop‐2‐enoate>, and methyl methacrylate (MMA) are some of the most commonly used monomers in the field of restorative dentistry. These compounds are characterized by having one or two terminal double bonds. Besides the effort to synthesize new monomers, several problems still affect the clinical behavior of contemporary dental materials. In this work, two monomers with three terminal double bonds, 5A13DA and 5A13DMA, were synthesized. Both monomers were used to completely replace TEGDMA as reactive diluent of photopolymerizable dental resin composites containing Bis‐GMA. The effects of 5A13DA and 5A13DMA on flexural properties, double bond conversion, water sorption, solubility, and polymerization shrinkage were evaluated. In addition, both monomers were evaluated as crosslinking agents for methylmethacrylate, resulting in copolymers with enhanced thermal stability. The results obtained suggest that newly synthesized monomers are potential substitutes for TEGDMA in the formulation of dental composites, providing 50% lower volumetric shrinkage than the composite resin used as control and adequate mechanical properties. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46240. 相似文献
948.
Yilun Liu Siqi Liu Hui Chen Xianqiong Zhao Chi Liu Tianxiang Wu Jiahui Su 《化学工程与技术》2018,41(5):913-920
The discharge process of granular material from a wedge‐shaped feed hopper was numerically simulated using a 3D discrete element method. The effects of particle size, feed pipe, side and rear wedge angle on the discharge performance were investigated in terms of flow pattern, discharge rate, and stability. The results show that with larger particle size the granular flow pattern gradually transforms from mass flow to edge flow where the flow rate decreases and the discharging integrity and stability become worse. The presence of the feed pipe reduces the discharge rate and stability. The increase of the feed pipe diameter will diminish the discharge rate and enhance the discharge stability. Both the side and the rear wedge angle have a certain effect on the discharge performance. The effects of feed pipe, side and rear wedge angle on the discharge stability become more significant with larger particle size. 相似文献
949.
Improvement of anti‐icing properties of low surface energy coatings by introducing phase‐change microcapsules 下载免费PDF全文
Polymers with low surface energy such as silicone and fluoropolymers are widely applied in preparing anti‐icing coatings, but they may have some limitations. To improve the anti‐icing properties of the coatings, composite coatings were developed by introducing phase‐change microcapsules (PCMs). Room temperature vulcanized silicone rubber and a fluorosilicone methacrylate copolymer were examined. Tests involving infrared thermal imaging, icing delay time, and ice shear strength were performed to determine the anti‐icing properties of the coatings. It was found that during cooling the composite coatings containing PCMs could release the latent heat of phase change to delay the icing process of water droplets on its surface. The introduction of PCMs increased the surface roughness, and the ice shear strengths of the composite coatings could remain at a low level and ice on the coatings could be easily removed, indicating that PCMs could be practicably applied in anti‐icing coatings. POLYM. ENG. SCI., 58:973–979, 2018. © 2017 Society of Plastics Engineers 相似文献
950.
Thermal‐cycle dependent residual stress within the crack‐susceptible zone in thermal barrier coating system 下载免费PDF全文
Peng Jiang Xueling Fan Yongle Sun Hongtao Wang Luochuan Su Tiejun Wang 《Journal of the American Ceramic Society》2018,101(9):4256-4261
Nondestructive and accurate measurement of residual stress in ceramic coatings is challenging, but it is crucial to the assessment of coatings failure and life. In this study, for the first time, the thermal‐cycle dependent residual stress in an atmosphere plasma sprayed thermal barrier coating system has been nondestructively and accurately measured using photoluminescence piezo‐spectroscopy. Each thermal cycle consists of a 5‐minute heating held at 1150°C and a 3‐minute water quenching. The measurement was performed within a crack‐susceptible zone in the yttria‐stabilized‐zirconia (YSZ) top coat (TC) closely above the thermally grown oxide layer. A YSZ:Eu3+ sublayer was embedded in TC as a stress sensor. It was found that the initial residual stress was compressive, with a mean value of 240 MPa, which rapidly increased to 395 MPa after 5 thermal cycles (12.5% life) and then increased gradually to the peak of 473 MPa after 25 thermal cycles (62.5% life). After 30 thermal cycles (75% life), the mean stress dropped abruptly to 310 MPa and became highly heterogeneous, with gradual reduction toward final spallation. The heterogeneous stress distribution indicates that many microcracks nucleated at different locations and the spallation occurred due to the coalescence of the microcracks. 相似文献