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71.
Aiming at the approximate measurement of magnetic rotation angle in optical current sensor based on light intensity detection mode, this paper proposes a current measurement method based on triangular constant transformation to reconstruct magnetic rotation angle, so as to avoid the large current measurement error caused by the approximate measurement of the magnetic rotation angle. By extracting the direct current (DC) component and the alternating current (AC) component of the light intensity signal detected by the photoelectric detector (PD), the sine signal containing the magnetic rotation angle is directly obtained by dividing the two components, and then the triangular identity transformation method is used to linearly demodulate the magnetic rotation angle and reconstruct the current waveform. The experimental results show that the relative error of current measurement does not exceed 1.40% in the current range of 0.05—0.50 A, which is less than the approximate linear measurement (ALM) method, and the magnetic rotation angle and the current have a good linear relationship. 相似文献
72.
Xiaohui Chen Niu Niu Dan Li Zicong Zhang Zeyan Zhuang Dingyuan Yan Jiangao Li Zujin Zhao Dong Wang Ben Zhong Tang 《Advanced functional materials》2023,33(8):2211571
Photoactivatable agent is a powerful tool in biomedicine studies due to high-precision spatiotemporal control of light. However, those previously reported agents generally suffer from short wavelength, fluorescence self-quenching effect, and the lack of photosensitizing property, which severely restrict their practical applications. To address these issues, molecular engineering of 1,4-dihydropyridine derivatives is conducted to obtain an optimized agent, namely TPA-DHPy-Py, which exhibits low oxidation potential, high photoactivation efficiency, and excellent type I/II combined photodynamic activity. Concurrently, its photoactivated counterpart is featured by aggregation-induced near-infrared emission and remarkable reactive oxygen species (ROS) production efficiency. Upon photoactivation, TPA-DHPy-Py is capable of precisely identifying cancer cells from co-culturing cancer cells and normal cells without the assistance of any extra targeting units, and in situ monitoring lipid droplets and endoplasmic reticulum alteration under ROS stress, as well as achieving fluorescent visualization of tumor in vivo with supremely high imaging contrast. Furthermore, the unprecedented performance on photodynamic cancer therapy is demonstrated by the significant inhibition of tumor growth. Therefore, the photoactivatable TPA-DHPy-Py with dual-organelle-targeted and excellent photodynamic activity associated with self-monitoring ability is highly promising for cancer theranostics in clinical trials. 相似文献
73.
Ultra-Stable and Sensitive Ultraviolet Photodetectors Based on Monocrystalline Perovskite Thin Films
Xu Li Chang Liu Feng Ding Zheyi Lu Peng Gao Ziwei Huang Weiqi Dang Liqiang Zhang Xiaohui Lin Shuimei Ding Bailing Li Ying Huangfu Xiaohua Shen Bo Li Xuming Zou Yuan Liu Lei Liao Yiliu Wang Xidong Duan 《Advanced functional materials》2023,33(15):2213360
The detection of ultraviolet (UV) radiation with effective performance and robust stability is essential to practical applications. Metal halide single-crystal perovskites (ABX3) are promising next-generation materials for UV detection. The device performance of all-inorganic CsPbCl3 photodetectors (PDs) is still limited by inner imperfection of crystals grown in solution. Here wafer-scale single-crystal CsPbCl3 thin films are successfully grown by vapor-phase epitaxy method, and the as-constructed PDs under UV light illumination exhibit an ultralow dark current of 7.18 pA, ultrahigh ON/OFF ratio of ≈5.22 × 105, competitive responsivity of 32.8 A W−1, external quantum efficiency of 10867% and specific detectivity of 4.22 × 1012 Jones. More importantly, they feature superb long-term stability toward moisture and oxygen within twenty-one months, good temperature tolerances at low and high temperatures. The ability of the photodetector arrays for excellent UV light imaging is further demonstrated. 相似文献
74.
Xiaohui Lin Long Chen Chenglin He Yiliu Wang Xu Li Weiqi Dang Kun He Ying Huangfu Dan Wu Bei Zhao Bo Li Jia Li Xidong Duan 《Advanced functional materials》2023,33(1):2210278
Single crystal metal halide perovskites thin films are considered to be a promising optical, optoelectronic materials with extraordinary performance due to their low defect densities. However, it is still difficult to achieve large-scale perovskite single-crystal thin films (SCTFs) with tunable bandgap by vapor-phase deposition method. Herein, the synthesis of CsPbCl3(1–x)Br3x SCTFs with centimeter size (1 cm × 1 cm) via vapor-phase deposition is reported. The Br composition of CsPbCl3(1–x)Br3x SCTFs can be gradually tuned from x = 0 to x = 1, leading the corresponding bandgap to change from 2.29 to 2.91 eV. Additionally, an low-threshold (≈23.9 µJ cm−2) amplified spontaneous emission is achieved based on CsPbCl3(1–x)Br3x SCTFs at room temperature, and the wavelength is tuned from 432 to 547 nm by varying the Cl/Br ratio. Importantly, the high-quality CsPbCl3(1–x)Br3x SCTFs are ideal optical gain medium with high gain up to 1369.8 ± 101.2 cm−1. This study not only provides a versatile method to fabricate high quality CsPbCl3(1–x)Br3x SCTFs with different Cl/Br ratio, but also paves the way for further research of color-tunable perovskite lasing. 相似文献
75.
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77.
使用光学显微镜、扫描电镜和透射电镜分析了Al-Zn-Mg合金和含微量钪的Al-Zn-Mg合金钨极氩弧焊接头的微观组织,并对其力学性能和耐应力腐蚀性能进行了对比。结果表明:在传统Al-Zn-Mg合金板材熔合线附近的热影响区出现再结晶和晶粒异常长大,而含钪Al-Zn-Mg合金基体中热稳定性优良的纳米Al3(Sc, Zr, Ti)相在焊接过程中能阻碍晶界迁移,抑制再结晶晶粒的形核和长大,进而细化熔合线附近的组织。同时,含微量钪的Al-Zn-Mg合金焊接接头的强度明显比传统合金的高,其强化效果主要来源于熔合线附近区域的细晶强化和二次Al3(Sc, Zr, Ti)相的弥散强化。 相似文献
78.
Xiaohui Chen Sheng Xu Huarui Yin Weidong Wang Guo Wei 《Personal and Ubiquitous Computing》2011,15(1):75-84
Connectivity is very important to enable ubiquitous computing. Wireless communication plays a continual key role in future
ubiquitous network where all devices need to be connected freely. Ultra-wideband (UWB) radio is a new method of short-range
wireless technology which is suit for ubiquitous computing. In this paper, we provided the potentials of impulse radio UWB
(IR-UWB) technology in ubiquitous computing environments. Our study investigated possible communication methods which can
be used in ubiquitous network. Comparisons between different communication technologies demonstrated that UWB-based solutions
can support identification, location, sensing, and connectivity. In addition, we proposed two typical schemes which show how
IR-UWB is used in ubiquitous computing. 相似文献
79.
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