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51.
A novel torsion sensor is proposed, which is composed of one long period fibre grating and one asymmetrically corrugated long period fibre grating based on the high-frequency CO2 laser pulses technology and burning fibre coating and etching cladding technology, respectively. By combing the advantages of the two aforementioned elements, a sensitivity of 331.7 and 310.3 pm/(rad/m) towards clockwise and anticlockwise direction, respectively, is reached in the experiments. 相似文献
52.
Chen J Luo Y Hong L Ling Y Pang J Fang Y Wei K Gao X 《Journal of materials science. Materials in medicine》2011,22(3):547-555
A superior drug controlled release system capable of achieving efficient osteogenesis is in imperative demand because of limited
bone substitute tissue for the treatment of bone defect. In the present study, we investigated the potential of using poly(ε-caprolactone)–hydroxyapatite
(PCL–HA) composite microspheres as an injectable bone repair vehicle by controlled release of alendronate (AL), a medicine
that belongs to the bisphosphonates family. The PCL/HA–AL microspheres were prepared with solid/oil/water emulsion technique,
which included two processes: (1) AL was loaded on the hydroxyapatite nanoparticles; (2) the HA–AL complex was built in the
PCL matrix. The spherical PCL/HA–AL microspheres were characterized with its significantly improved encapsulation efficiency
of hydrophilic AL and better sustained release. Human bone mesenchymal stem cells (hMSCs) were cultured on the surface of
these microspheres and exhibited high proliferative profile. Specifically, in osteogenic medium, hMSCs on the surface of PCL/HA–AL
microspheres displayed superior osteogenic differentiation which was verified by alkaline phosphatase activity assay. In conclusion,
by presenting strong osteogenic commitment of hMSCs in vitro, the PCL/HA–AL microspheres have the potential to be used as
an injectable vehicle for local therapy of bone defect. 相似文献
53.
Background The accelerator-driven subcritical transmuta-tion system(ADS)is an advanced technology for the harmless disposal of nuclear waste.A theoretical analy... 相似文献
54.
55.
Cheng Wang Jian-Hao Tan Xiao-Xia Huang Yi-Xing Lu Lin Wang Wen-Cheng Fang Zhen-Tang Zhao 《核技术(英文版)》2021,32(9):84-93
To further improve the performance of acceler-ators, the first cryogenic normal-conducting RF gun in China was designed and manufactured. As a new and attractiv... 相似文献
56.
57.
In this study,by changing both pier diameters and particle sizes of sand bed in flume experiments,the scour process around cylindrical bridge piers under an ice... 相似文献
58.
Yinian Feng Bo Zhang Chen Zhi Ke Liu Weilong Liu Fang Shen Chuanqi Qiao Jicong Zhang Yong Fan Xiaobo Yang 《中国通信》2021,(5):210-220
With the successful demonstration of terahertz (THz) high-speed wireless data transmission,the THz frequencies are now becoming a worth candidate for post-5G wi... 相似文献
59.
60.
Lei Wang Xiaoqing Gong Yongqin Zhang Pengfei Xu Xiaojiang Chen Dingyi Fang Xia Zheng Jun Guo 《Multimedia Tools and Applications》2018,77(3):2973-2990
Chinese calligraphy is a unique visual art, and and is one of the material basis of China’s traditional cultural heritage. However, time had caused the old calligraphy works to weathering and damages, so it is necessary to utilize advanced technologies to protect those works. One of those technologies is digital imaging, and the obtained images by digital imaging can preserve the visual information of calligraphy works better, furthermore, they can be used in further researches. While the basic works for those researches are to extract the artistic features which include two elements, i.e., form and spirit. However, most of the existing methods only extract the form and ignore the characters’ spirit, especially they are insensitive to the slight variation in complex ink strokes. To solve these problems, this paper proposes an extraction method based on regional guided flter (RGF) with reference images, which is generated by KNN matting and used as the input image for RGF. Since RGF is sensitive to the slight variation of ink, so the detailed information of the inside of strokes can be detected better. Besides, unlike the past works, which filter the whole strokes, RGF filters the inside of strokes and edges in different windows respectively, which results in that the edges are preserved accurately. Results from a deployment of several famous Chinese calligraphy works demonstrate that our method can extract more accurate and complete form and spirit with lower error rate. 相似文献