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41.
激光二极管泵浦的高效、单频Nd:YVO4激光器 总被引:2,自引:0,他引:2
对激光二极管端面泵浦的单频Nd:YVO4激光器进行了研究,研究了不同输出耦合率情况下输出功率随泵浦功率的变化曲线及光-光转化效率随输出耦合率的变化曲线,实验结果与理论分析结果基本一致.当泵浦功率为2.2 W时,得到瓦级单频1064 nm激光输出,最高光-光转化效率为47.2%. 相似文献
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含稀土抗蠕变压铸镁合金的开发 总被引:5,自引:0,他引:5
针对商用压铸镁合金抗高温蠕变性能较差的现状,开发了抗高温蠕变压铸镁合金,其开发的目的是针对大马力柴油发动机汽缸罩盖,其抗高温蠕变性能应该能够保障其在150℃条件下稳定工作,而且其成本的增加应该控制在AZ91D合金成本的15%以内。讨论了稀土元素Ce,Y,Nd及Ca和Si的添加对压铸镁合金在常温拉伸性能以150℃条件下的蠕变行为、显微组织的影响,以及对表面处理和腐蚀试验的影响,并进行了实际产品的压铸牛产。试验结果表明,所开发的抗蠕变压铸镁合金具有应用于汽车动力系统部件的制造并大幅度减轻重量的潜力。 相似文献
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Xu Lei Li Yaohui Mu Yuanchun Chen Wei Zhang Fan Wang Jinzhen Zu Chenkui 《Journal of Sol-Gel Science and Technology》2021,99(2):413-419
Journal of Sol-Gel Science and Technology - The silica sol and potassium hydroxide solution are mixed under certain conditions to form a precursor solution, which is poured into a closed cavity and... 相似文献
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We demonstrate a 7-bit photonic true-time-delay (TTD) system which uses an 8 × 8 micro-optical-electro- mechanical system (MOEMS) optical switch for phased array antennas (PAAs) beamforming applications. The switch controls the optical signal to pass by the fiber delay lines (FDLs) of different lengths. Different time delays between adjacent channels are obtained due to the chromatic dispersion of FDLs. Therefore, the system cannot be disturbed by the environment. The measured time delay responses are nearly linear with the wavelength spacing between optical carriers as well as the lengths of FDLs, which agrees well with the theoretical analysis. 相似文献
46.
Jian Liu Yaohui Zhu Peisong He Xiaosong Chen Jing-Dong Bao 《The European Physical Journal B - Condensed Matter and Complex Systems》2017,90(4):70
Anomalous diffusion is researched within the framework of the coupled continuous time random walk model, in which the space-time coupling is considered through the correlated function g(t) ~ t γ , 0 ≤ γ< 2, and the probability density function ω(t) of a particle’s transition time t follows a power law for large t: ω(t) ~ t ? (1 + α),1 <α< 2. The bi-fractional generalized master equation is derived analytically which can be applied to describe the transient bi-fractional diffusion phenomenon which is induced by the space-time coupling and the asymptotic behavior of ω(t). Numerical results show that for the transient bi-fractional diffusion, there is a transition from one fractional diffusion to another one in the diffusive process. 相似文献
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Yaohui Liang Prof. Chao Xu Huaqing Zhang Shiying Wu Jian-An Li Yifan Yang Dr. Zhu Mao Prof. Suilian Luo Prof. Cong Liu Prof. Guang Shi Prof. Fengqiang Sun Prof. Zhenguo Chi Prof. Bingjia Xu 《Angewandte Chemie (International ed. in English)》2023,62(7):e202217616
Color-tunable dual-mode organic afterglow excited by ultraviolet (UV) and white light was achieved from classical aggregation-caused quenching compounds for the first time. Specifically, two luminescent systems, which could produce significant organic afterglow composed of persistent thermally activated delayed fluorescence and ultralong organic phosphorescence under ambient conditions, were constructed by doping fluorescein sodium and calcein sodium into aluminum sulfate. Their lifetimes surpassed 600 ms, and the dopant concentrations were as low as 5×10−6 wt %. Moreover, the persistent luminescence colors of the materials could be tuned from blue to green and then to yellow by simply varying the concentrations of guest compounds or the temperature in the range of 260–340 K. Inspired by these exciting results, the afterglow materials were used for UV- and white-light-manipulated anti-counterfeiting and preparation of elastomers with different colors of persistent luminescence. 相似文献
50.
Guihua Zhang Dr. Yaohui Wang Weihang Zhou Dr. Yanmei Lei Prof. Dr. Jinsong Lu Prof. Dr. Wenjin Yin Prof. Dr. Zhi Zhu Prof. Dr. Chaoyong Yang Prof. Dr. Peng Zhang 《Angewandte Chemie (International ed. in English)》2023,62(51):e202315113
The protein phenotypes of extracellular vesicles (EVs) have emerged as promising biomarkers for cancer diagnosis and treatment monitoring. However, the technical challenges in rapid isolation and multiplexed molecular detection of EVs have limited their clinical practice. Herein, we developed a magnetically driven tandem chip to achieve streamlined rapid isolation and multiplexed profiling of surface protein biomarkers of EVs. Driven by magnetic force, the magnetic nanomixers not only act as tiny stir bars to promote mass transfer and enhance reaction efficiency of EVs, but also transport on communicating vessels of the tandem chip continuously and expedite the assay workflow. We designed cyclic surface enhancement of Raman scattering (SERS) tags to bind with target EVs and then release them by exonuclease I, eliminating steric hindrance and amplifying the SERS signal of multiple protein biomarkers on EVs. Due to the excellent assay performance, six breast cancer biomarkers were detected simultaneously on EVs using only 10 μL plasma within 1.5 h. The unweighted SUM signature offers great accuracy in discriminating breast cancer patients from healthy donors. Overall, the dynamic magnetic driving tandem chip offers a new avenue to advance the clinical application of EV-based liquid biopsy. 相似文献