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141.
142.
针对SILEX-I超短超强脉冲激光装置输出光束光谱分布的精密测量问题,采用脉冲激光相对光谱功率来评价光谱分布,以溴钨灯为标准光源开展相对光谱功率测量方法的研究,获得相对光谱功率的理论计算公式。以SP2760光栅光谱仪作为光谱测量设备在SILEX-I激光装置上进行了光谱分布测量的验证实验,并给出了不确定度评定,获得了扩展相对不确定度1.7%的测量精度。测量结果显示,相对光谱功率分布与光栅光谱仪的原始光谱响应值分布具有显著的差异,可以更加准确地反映输出脉冲的光谱分布。 相似文献
143.
针对光学元件损伤图像中损伤区域的高精度检测问题,对内全反射照明下光学元件损伤图像的处理技术进行了研究。根据在线检测图像中损伤区域中心峰值的信号强度高于局部背景的信号强度这一特点,利用高斯滤波器生成待检测图像的局部信号强度比图像,实现了对损伤区域的低漏检率自动定位;根据CCD的成像原理,利用辐射标定的方法建立起损伤区域的尺寸与其在图像中总灰度的关系方程,实现了损伤区域的亚像素高精度尺寸测量。实验结果表明,与传统的光学元件损伤图像处理算法相比,本文提出的算法在保持低漏检率的同时大大提高了损伤区域的测量精度。 相似文献
144.
Dongming Xu Xueting Ren Haoyu Li Yuran Zhou Simin Chai Yining Chen Hang Li Lishun Bai Prof. Zhi Chang Prof. Anqiang Pan Prof. Haoshen Zhou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(21):e202402833
Aqueous zinc-metal batteries (AZMBs) usually suffered from poor reversibility and limited lifespan because of serious water induced side-reactions, hydrogen evolution reactions (HER) and rampant zinc (Zn) dendrite growth. Reducing the content of water molecules within Zn-ion solvation sheaths can effectively suppress those inherent defects of AZMBs. In this work, we originally discovered that the two carbonyl groups of N-Acetyl-ϵ-caprolactam (N-ac) chelating ligand can serve as dual solvation sites to coordinate with Zn2+, thereby minimizing water molecules within Zn-ion solvation sheaths, and greatly inhibit water-induced side-reactions and HER. Moreover, the N-ac chelating additive can form a unique physical barrier interface on Zn surface, preventing the harmful contacting with water. In addition, the preferential adsorption of N-ac on Zn (002) facets can promote highly reversible and dendrite-free Zn2+ deposition. As a result, Zn//Cu half-cell within N-ac added electrolyte delivered ultra-high 99.89 % Coulombic efficiency during 8000 cycles. Zn//Zn symmetric cells also demonstrated unprecedented long life of more than 9800 hours (over one year). Aqueous Zn//ZnV6O16 ⋅ 8H2O (Zn//ZVO) full-cell preserved 78 % capacity even after ultra-long 2000 cycles. A more practical pouch-cell was also obtained (90.2 % capacity after 100 cycles). This method offers a promising strategy for accelerating the development of highly efficient AZMBs. 相似文献
145.
Hall效应对三维磁流体发生器的影响 总被引:3,自引:0,他引:3
应用三维非理想低磁雷诺数磁流体五方程模型发展了对带有强制项的Navier-Stokes方程组采用熵条件格式, 对椭圆型电势方程采用SOR进行迭代的数值方法,研究了Hall效应对磁流体旁路超燃冲压发动机中磁流体发生器流动及性能的影响.磁流体发生器采用电子束获得有效可靠的电导率. 计算结果表明,Hall效应可引起流场和电场的扭曲, 从而诱导出不稳定二次流的发展与演变,并破坏Joule热的分布. 对这些磁流体现象作出了较详细的分析.最后计算了磁流体发生器的性能参数, 说明Hall效应将导致磁流体发生器的性能下降. 相似文献
146.
Yueyan Cao Qiang Zhu Yuguo Huang Xi Li Yifan Wei Haoyu Wang Ji Zhang 《Electrophoresis》2022,43(16-17):1774-1783
In forensic genetics, the use of ancestry informative single-nucleotide polymorphisms (AISNPs) panels can narrow the direction of the investigation by estimating an individual's biogeographic ancestry. However, distinguishing subgroups within continental regions requires more specific panels. In this study, we screened 19 AISNPs from the 1000 Genomes Project (1KG) based on their FST values to distinguish target populations in East Asia and obtained genotypes through SNaPshot. The 19 AISNPs could divide the global population of the 1KG into five clusters and could further divide the East Asian population into four clusters: Japanese, Han Chinese, Dai Chinese, and Kinh in Ho Chi Minh City of Vietnam. In summary, the 19-AISNP panel may serve as a useful and cost-effective tool for forensic ancestry inference in East Asian populations at a finer scale. 相似文献
147.
Yiran Jiao Chen Ling Jie-Xin Wang Honeyfer Amanico Joshua Saczek Haoyu Wang Sreepathy Sridhar Ben Bin Xu Steven Wang Dan Wang 《Particle & Particle Systems Characterization》2020,37(9):2000129
Upconversion nanophosphors (UCNPs) are considered as an important synthesis arm within biomedical and energy sectors due to their unique optical characteristics, which can convert near-infrared light into higher energy emissions. However, key challenges, cost, compatibility of the materials, etc. have to be taken into serious consideration to transform this in-lab UCNPs technology into scale-up production for wider commercial needs. This review highlights the fundamental concepts of synthetic approaches for UCNPs and recaps recent advances in terms of large-scale production. A number of typical synthesis routes in both batch and continuous processes are reviewed, alongside their limitations and potential improvements when being considered for mass production. By discussing and exploiting the technical compacity for the potential synthetic trends, key challenges, and expectations of future synthesis methods for UCNPs are also outlined. 相似文献
148.
We report a feasibility study for violation in τ-→ KSπ-vτ decays at a Super Tau Charm Facility (STCF).With an expected luminosity of 1 ab-1 collected by STCF pe... 相似文献
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