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91.
Zhenguo Shi Shifeng Zhou Zhongmin Yang 《Journal of the American Ceramic Society》2021,104(5):2030-2038
Flexible scintillating fiber plays an important role in X-ray radiation monitoring and high-resolution medical imaging, while construction of scintillating fiber derived from the commercial material system meet with limited success. Here, we report the design and successful fabrication of the Ce-activated lutetium aluminum silicate glass, nanostructured glass, and fiber, and explore their scintillating properties. The scintillating glass with optimized composition and optical properties is determined. The crystallization behavior of lutetium aluminum silicate glass is studied and the nanostructured glass embedded with orthorhombic Lu2Si2O7 phase is successfully constructed for the first time. Importantly, the crystalline layer thickness of the nanostructured glass can be finely tuned and ~172.89% enhancement in the scintillating performance can be achieved. Furthermore, the fiber with large sized core is fabricated and its radiation response properties are tested. The results show that it exhibits high sensitivity and its scintillating emission is lineally dependent on the X-ray power, indicating the potential application for radiation detection. 相似文献
92.
Simultaneous control of the chemical state and local environment of Cr dopant in glass for extended emission 下载免费PDF全文
Jiejie Chen Yongze Yu Hao Luo Liting Lin Shifeng Zhou 《Journal of the American Ceramic Society》2018,101(1):159-166
Control of the chemical state and local environment of Cr dopant in glass through self‐limited nanocrystallization is presented. Interesting wavelength‐tunable and ultra‐broadband near‐infrared luminescence with the full width at half maximum of about 380 nm from obtained Cr‐activated glass‐ceramics are demonstrated. The results indicate that the presented method may be an effective means of fabricating multifunctional optical gain materials and wideband fiber light sources. 相似文献
93.
本文介绍辅助绘图系统的设计思想、辅助绘图系统通用接口、设备结构参数输入及绘图数据计算等主要程序结构、数据及图形管理、用户开发方法等。 相似文献
94.
Fang Guan Yiquan Wu Iva Milisavljevic Xin Cheng Shifeng Huang 《Journal of the American Ceramic Society》2021,104(10):5148-5156
Spinel-structured NiMn2O4 ceramics, with different valence Ni sources, were originally prepared using Ni2O3 and NiO as raw materials, and the effects of different valence Ni sources on their electrical properties were first investigated. XRD patterns show that both Ni2O3-based and NiO-based NiMn2O4 ceramics are single cubic spinel structures. SEM/EDS images indicate that the NiMn2O4 ceramics exhibited high density at the experiment-determined sintering temperatures. XPS results and Raman drifts prove that the Ni valence-induced changes in Mn ions at B sites played a significant role in the electrical properties and thermal stability of NiMn2O4 ceramics. Compared with NiO-based NiMn2O4, the resistivity at 25°C (ρ25°C) of Ni2O3-based NiMn2O4 increased dramatically from 3109 to 106958 Ω cm, the thermal constant (B25/50) increased from 3264 to 4473 K, and the resistance shifts after annealing for 1000 h at 150°C decreased from 0.80% to 0.74%. The investigation of the relationship between the material properties and valence of Ni sources has provided a new and effective way for designing the spinel-structured negative temperature coefficient (NTC) materials by modulating the valence of ions at A sites in the raw materials. 相似文献
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Yingying Wang Qinggang Li Shifeng Huang Xin Cheng Pengkun Hou Yongchen Wang Guanliang Chen Shanling Yi 《Ceramics International》2018,44(1):471-476
Aluminum oxynitride (AlON) powders were synthesized using the raw materials of γ-Al2O3 and carbon black through the carbothermal reduction and nitridation process. The carbon content in the γ-Al2O3/C mixture and heating temperature were investigated. The AlON powders were synthesized by calcination for 2 h at 1750 °C when the carbon content in the γ-Al2O3/C mixture was 5.8 wt%. The particle size of powder is important to the transparency of ceramics, but the size of the synthesized powder was large. Therefore, a few methods, such as freeze-drying, ultrasonic dispersion, and liquid nitrogen ball milling, were used to reduce the particle size of powders. Among the three methods, liquid nitrogen milling had the best results. 相似文献
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Electron beam (EB) irradiation of polyvinyl chloride (PVC) was carried out in the presence of three different ethylene–vinyl acetate copolymers (EVA). The mechanical properties of the original and irradiated blends were tested. The gel content measurement, chlorine loss upon electron irradiation, and gel permeation chromatograph (GPC) were used to characterize the effect of EVA on the irradiation behavior of PVC/EVA blends. The content and the chemical structure of EVA in the blends had considerable effects on the mechanical properties and gel content of the blends. The incorporation of EVA into PVC blend can increase the gel content and reduce chlorine loss of the blends. The GPC analysis of the soluble part in the irradiated PVC samples showed that the addition of EVA into the PVC blend lowered the polydispersity of molecular weight of PVC. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1571–1575, 2004 相似文献
100.
Qiangbing Guo Xiaofeng Liu Shifeng Zhou 《Journal of the American Ceramic Society》2015,98(10):2976-2979
Here, we demonstrate the relationship between glass network topological structure and the chemical state of embedded lanthanide ions. It is revealed that a more dispersed state of lanthanide ions is shown in more constrained 3D rigid network, which delivers valuable information toward homogeneous doping in glasses from the perspective of glass topological structure. The results are believed to be of great significances in the development of advanced optoelectronic devices like high‐power laser, efficient fiber amplifier, smaller integrated photonic circuit, etc. 相似文献