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101.
The rapid development of new energy in the distribution network increases its flexibility while making it more complicated to operate and manage the network. For this reason, a novel flexible switch, which is composed of integrated gate- commutated thyristors (IGCT) and parallel voltage converters, is proposed in this paper. Applying virtual synchronous generator (VSG) control on the parallel voltage converterensures smoothness and steadiness while switching from one feeder to another. Firstly, the proposed flexible switch is compared with the flexible multi-state switch and the mechanical switch on their main characteristics. Then, the operating features of the flexible switch before, during, and after feeder fault are analyzed, as well as its switching logic. Finally, the switching process between different feeders is simulated on a control in-the-loop experiment based on RT-Lab. The voltage and current waveforms are obtained under different operating modes and during flexible switching. The experiment resultsshow that the flexible switch has short-term voltage support capability and does not generate voltage and current impulses during the switching process. © 2023, Editorial Department of Electric Power Engineering Technology. All rights reserved. 相似文献
102.
Chunya Du Hui Liu Zhuang Cheng Shaoqin Zhang Zexing Qu Dezhi Yang Xianfeng Qiao Zujin Zhao Ping Lu 《Advanced functional materials》2023,33(45):2304854
The pursuit for efficient deep blue material is an ever-increasing issue in organic optoelectronics field. It is a long-standing challenge to achieve high external quantum efficiency (EQE) exceed 10% at brightness of 1000 cd m−2 with a Commission International de L'Eclairage (CIEy) <0.08 in non-doped organic light-emitting diodes (OLEDs). Herein, this study reports a deep blue luminogen, PPITPh, by bonding phenanthro[9,10-d]imidazole moiety with m-terphenyl group via benzene bridge. The non-doped OLED based on PPITPh exhibits an exceptionally high EQE of 11.83% with a CIE coordinate of (0.15, 0.07). The EQE still maintains 10.17% at the brightness of 1000 cd m−2, and even at a brightness as high as 10000 cd m−2, an EQE of 7.5% is still remained, representing the record-high result among non-doped deep-blue OLEDs at 1000 cd m−2. The unprecedented device performance is attributed to the reversed intersystem crossing process through hot exciton mechanism. Besides, the maximum EQE of orange phosphorescent OLED with PPITPh as host is 32.02%, and remains 31.17% at the brightness of 1000 cd m−2. Such minimal efficiency roll-off demonstrates that PPITPh is also an excellent phosphorescent host material. The result offers a new design strategy for the enrichment of high-efficiency deep blue luminogen. 相似文献
103.
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
104.
Zhe Zhang Peng He Wenjun Ma Peiyuan Zuo Xiaoyun Liu Qixin Zhuang 《Advanced functional materials》2023,33(33):2302212
Herein, a facile, controllable, and versatile method is reported to prepare monodisperse yolk-shell and yolk-multishell silica nanoparticles (NPs) with mesoporous shells by a novel selective etching strategy. The mechanism of selective etching based on fluoride-silica chemistry is investigated in detail and thus provides a fundamentally novel principle for the fabrication of yolk-shell NPs. Specifically, this unprecedented and versatile synthesis strategy can be used to encapsulate essentially any silica-based, carbon-based, metal, metal oxide, or other possible NPs. Noteworthy is that most of the yolk-shell mesoporous silica (mSiO2) NPs are prepared for the first time. To demonstrate the major structural and compositional advantages of the designed yolk-shell NPs, their applications in the fields of ultralow-dielectric constant (k) materials, drug delivery systems, and catalysts were explored. In detail, the lowest k value of the prepared yolk-shellordered mesoporous silica@mSiO2/fluorinated polybenzoxazole composite films is 2.02; The obtained yolk-shell mSiO2/C@mSiO2/C NPs possess high hydrophilicity and pH-responsive sensitivity; The conversion of the catalytic reaction of the designed magnetic yolk-shell hollow Fe3O4@SiO2/Au@mSiO2 NPs at 20 min is 97% with a high conversion rate (92%) and recyclability even after 10 reuses. This innovative work lays a solid foundation for freely tailorable yolk-shell encapsulation and will greatly stimulate more efforts devoted to relevant research and development. 相似文献
105.
Haotian Wang Jian Sun Hong Ding Ganlin Shan Zhuang Chang 《Journal of Failure Analysis and Prevention》2017,17(6):1182-1190
Performance degradation modeling plays an important role in prognostics and health management of mechanical system. Influenced by the complex structure of the hydraulic pump and the limited experiment standards, it is hard to establish an appropriate performance degradation model. To fulfill current requirements, a method for establishing the performance degradation model based on accelerated experiment is proposed. In order to describe the general trend of the degradation, the double-stress exponential model is firstly established as the theoretical degradation model. On this basement, combined with the characteristics of the experiment, the accelerating coefficient is settled; meanwhile, the procedures for assuring the model parameters are presented. Furthermore, based on the accelerated experiment of the hydraulic pump under various stresses, the performance degradation model is finally established. Result of the experimental analysis indicates that the proposed method is applicable and the presented model is effective to measure the performance degradation of pump. 相似文献
106.
Polypyrrole Whelk‐Like Arrays toward Robust Controlling Manipulation of Organic Droplets Underwater 下载免费PDF全文
Xianyong Lu Zhuang Kong Guozheng Xiao Chao Teng Yunan Li Guangyuan Ren Shuangbao Wang Ying Zhu Lei Jiang 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(40)
Whelk‐like polypyrrole (PPy) arrays film is successfully prepared by electropolymerization of pyrrole in the presence of low‐surface‐energy tetraethylammonium perfluorooctanesulfonate (TEAPFOS) as dopant. The underwater wettability of PPy whelk‐like arrays can be successfully tuned by electrical doping/dedoping of PFOS ions. Interestingly, CCl4 droplets with microliter‐size as a representative sample are gathered together to form a larger droplet underwater at the potential of +0.8 V (vs Ag/AgCl), because PPy is in its PFOS‐doped states. Note that CCl4 droplet can climb uphill successfully on the inclined whelk‐like arrays PPy film under the applied potential of ?1.0 V (vs Ag/AgCl), which may be attributed to wettability gradient derived from different oxidation states of PPy induced by electrochemical potential. These results may provide a simple strategy for on‐demand manipulation of organic droplets underwater at low voltage. 相似文献
107.
Xiaoxia Wang Hong Zhou Shuangping Yuan Weihao Zheng Ying Jiang Xiujuan Zhuang Hongjun Liu Qinglin Zhang Xiaoli Zhu Xiao Wang Anlian Pan 《Nano Research》2017,10(10):3385-3395
High-performance multiphoton-pumped lasers based on cesium lead halide perovskite nanostructures are promising for nonlinear optics and practical frequency upconversion devices in integrated photonics.However,the performance of such lasers is highly dependent on the quality of the material and cavity,which makes their fabrication challenging.Herein,we demonstrate that cesium lead halide perovskite triangular nanorods fabricated via vapor methods can serve as gain media and effective cavities for multiphoton-pumped lasers.We observed blue-shifts of the lasing modes in the excitation fluence-dependent lasing spectra at increased excitation powers,which fits well with the dynamics of Burstein-Moss shifts caused by the band filling effect.Moreover,efficient multiphoton lasing in CsPbBr3 nanorods can be realized in a wide excitation wavelength range (700-1,400 nm).The dynamics of multiphoton lasing were investigated by time-resolved photoluminescence spectroscopy,which indicated that an electron-hole plasma is responsible for the multiphoton-pumped lasing.This work could lead to new opportunities and applications for cesium lead halide perovskite nanostructures in frequency upconversion lasing devices and optical interconnect systems. 相似文献
108.
109.
110.
Ultrathin 2D Zirconium Metal–Organic Framework Nanosheets: Preparation and Application in Photocatalysis 下载免费PDF全文
Ting He Bing Ni Simin Zhang Yue Gong Haiqing Wang Lin Gu Jing Zhuang Wenping Hu Xun Wang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(16)
Synthesizing ultrathin 2D metal–organic framework nanosheets in high yields has received increasing research interest but remains a great challenge. In this work, ultrathin zirconium‐porphyrinic metal–organic framework (MOF) nanosheets with thickness down to ≈1.5 nm are synthesized through a pseudoassembly–disassembly strategy. Owing to the their unique properties originating from their ultrathin thickness and highly exposed active sites, the as‐prepared ultrathin nanosheets exhibit far superior photocatalysis performance compared to the corresponding bulk MOF. This work highlights new opportunities in designing ultrathin MOF nanosheets and paves the way to expand the potential applications of MOFs. 相似文献