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991.
面向激光增材制造钛合金表面的光整加工需求,设计出一种多磁极耦合旋转磁场光整加工装置来研究光整加工特性。基于ANSYS Maxwell仿真软件分析了光整加工装置的磁场强度分布。搭建了实验光整平台,分析了主轴转速、C轴转速和加工间隙对表面质量的影响。结果表明,在主轴转速500 r/min、C轴转速160 r/min和加工间隙0.7 mm的加工条件下,表面粗糙度Ra由5.991 μm下降至0793 μm。扫描电子显微镜(SEM)观测表明,光整后的钛合金表面沉积层消失,表面质量得到显著改善。 相似文献
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Synthesis and thermophysical properties of RETa3O9 (RE = Ce,Nd, Sm,Eu, Gd,Dy, Er) as promising thermal barrier coatings 下载免费PDF全文
Lin Chen YeHua Jiang XiaoYu Chong Jing Feng 《Journal of the American Ceramic Society》2018,101(3):1266-1278
Thermal barrier coatings (TBCs) are one of the most important materials in gas turbine to protect the high temperature components. RETa3O9 compounds have a defect‐perovskite structure, indicating that they have low thermal conductivity, which is the critical property of TBCs. Herein, dense RETa3O9 bulk ceramics were fabricated via solid‐state reaction. The crystal structure was characterized by X‐ray diffraction (XRD) and Raman Spectroscope. Scanning electron microscope (SEM) was used to observe the microstructure. The thermophysical properties of RETa3O9 were studied systematically, including specific heat, thermal diffusivity, thermal conductivity, thermal expansion coefficients, and high‐temperature phase stability. The thermal conductivities of RETa3O9 are very low (1.33‐2.37 W/m·K, 373‐1073 K), which are much lower than YSZ and La2Zr2O7; and the thermal expansion coefficients range from 4.0 × 10?6 K?1 to 10.2×10?6 K?1 (1273 K), which is close to La2Zr2O7 and YSZ. According to the differential scanning calorimetry (DSC) curve there is not phase transition at the test temperature. Due to the high melting point and excellent high‐temperature phase stability with these oxides, RETa3O9 ceramics were promising candidate materials for TBCs. 相似文献
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Wenjun Shan Ronghe Chen Qiang Zhang Jie Zhao Binbin Chen Xi Zhou Shefang Ye Shengli Bi Liming Nie Lei Ren 《Advanced materials (Deerfield Beach, Fla.)》2018,30(28)
In recent years, hepatitis B core protein virus‐like particle (HBc VLP) is an impressive biomaterial, which has attracted considerable attention due to favorable properties such as structural stability, high uptake efficiency, and biocompatibility in biomedical applications. Heretofore, only a few attempts have been made to apply it in physical, chemical, and biological therapy for cancer. In this study, a tumor‐targeting RGD‐HBc VLP is first fabricated through genetic engineering. For image‐guided cancer phototherapy, indocyanine green (ICG) is loaded into RGD‐HBc VLP via a disassembly/reassembly pathway and electrostatic attraction with high efficiency. The self‐assembled stable RGD‐HBc VLP significantly improves body retention (fourfold longer), aqueous stability, and target specificity of ICG. Remarkably, these positive reformations promote more accurate and sensitive imaging of U87MG tumor, as well as prolonged tumor destruction in comparison with free ICG. Moreover, the photothermal and photodynamic effect on tumors are quantitatively differentiated by multiple linear regression analysis. Overall, less‐potent medicinal ICG can be perfectly rescued by bioengineered HBc VLP to realize enhanced cancer optotheranostics. 相似文献
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Xingguang Chen Beibei Chu Huiting Xi Junjun Xu Lizhi Lai Huifeng Peng Danwen Deng Ganhui Huang 《Journal of dairy science》2018,101(11):9647-9658
Chloride ion concentration in milk was determined by pulsed amperometric detection in a flow injection system. Results showed that the Au electrode lost 3 electrons at 1.10 V and formed chloroaurate ions (AuCl4?) by combining with chloride ions, after which AuCl4? was partly reduced to Au at 0.6 V. Based on the electrochemical process, a triple waveform with detection potential of 1.15 V, detection time of 150 ms, oxidation potential of 1.4 V, oxidation time of 550 ms, reduction potential of 0 V, and reduction time of 400 ms was applied to the Au electrode for detecting chloride ion concentration in milk. The approach is rapid and automatic and features a detection limit of 0.005 g/L. The relative standard deviation obtained by 60 repetitive injections reached 1.48% at 2 g/L of NaCl. The method developed using the Au electrode without modification was used to analyze the chloride ion concentration in raw milk without preprocessing. The method showed good agreement with potentiometric titration. 相似文献
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