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471.
配电网中馈线终端设备由于运行环境恶劣,往往面临意外失效问题。本文针对海量馈线终端装置的失效率预测问题,使用堆叠降噪自编码器实现基于馈线终端的各个关键元件的失效率预测;采用基于Dropout的模型正则化方法防止自编码器训练过程中出现过拟合现象,同时采用Adadelta算法对堆叠自编码器进行优化,在保证预测准确率的同时提高学习速率,实现馈线终端故障失效率的高效准确预测;最后基于馈线终端装置现场数据进行仿真验证。仿真结果验证了本文方法对失效率预测的准确性和泛化能力。 相似文献
472.
Zixin Yang Lili Han Qi Yang Xianghe Ren Syed Zaheer Ud Din Xiaoyan Zhang Jiancai Leng Jiabao Zhang Baitao Zhang Kejian Yang Jingliang He Chunlong Li Jun Wang 《中国光学快报(英文版)》2021,(3):64-68
Two-dimensional(2 D) Te nanosheets were successfully fabricated through the liquid-phase exfoliation(LPE) method. The nonlinear optical properties of 2 D Te nanosheets were studied by the open-aperture Z-scan technique. Furthermore, the continuous wave mode-locked Nd:YVO_4 laser was successfully realized by using 2 D Te as a saturable absorber(SA) for the first time, to the best of our knowledge. Ultrashort pulses as short as 5.8 ps were obtained at 1064.3 nm with an output power of 851 m W. This primary investigation indicates that the 2 D Te SA is a promising photonic device in the fields of ultrafast solid-state lasers. 相似文献
473.
Michio Kurosu Katsuhiko Mitachi Junshu Yang Edward V. Pershing Bruce D. Horowitz Eric A. Wachter John W. Lacey III Yinduo Ji Dominic J. Rodrigues 《Molecules (Basel, Switzerland)》2022,27(1)
Rose bengal has been used in the diagnosis of ophthalmic disorders and liver function, and has been studied for the treatment of solid tumor cancers. To date, the antibacterial activity of rose bengal has been sporadically reported; however, these data have been generated with a commercial grade of rose bengal, which contains major uncontrolled impurities generated by the manufacturing process (80–95% dye content). A high-purity form of rose bengal formulation (HP-RBf, >99.5% dye content) kills a battery of Gram-positive bacteria, including drug-resistant strains at low concentrations (0.01–3.13 μg/mL) under fluorescent, LED, and natural light in a few minutes. Significantly, HP-RBf effectively eradicates Gram-positive bacterial biofilms. The frequency that Gram-positive bacteria spontaneously developed resistance to HP-RB is extremely low (less than 1 × 10−13). Toxicity data obtained through our research programs indicate that HP-RB is feasible as an anti-infective drug for the treatment of skin and soft tissue infections (SSTIs) involving multidrug-resistant (MDR) microbial invasion of the skin, and for eradicating biofilms. This article summarizes the antibacterial activity of pharmaceutical-grade rose bengal, HP-RB, against Gram-positive bacteria, its cytotoxicity against skin cells under illumination conditions, and mechanistic insights into rose bengal’s bactericidal activity under dark conditions. 相似文献
474.
Polymer-bonded sugars (PBSs) can be used as a substitute material for polymerbonded explosives (PBXs) due to their ability to simulate the mechanical properties... 相似文献
475.
Crystallography Reports - A di-nuclear uranyl complex with the formula of [(UO2)2(L)4(H2O)2]?4H2O (1) (HL = quinoline-6-carboxylic acid) was synthesized hydrothermally and characterized by... 相似文献
476.
477.
Polymer dispersions, even in very low concentrations, can improve the performance of cholesteric liquid crystal materials necessary for their application in flat panel displays. Normal scattering mode, reverse scattering mode and reflective mode cholesteric liquid crystal materials are described. The roll of the polymer in each of these display modes is reviewed as are the unique electro-optic characteristics of the dispersions. 相似文献
478.
Oskar Nuyken Gerhard Maier Michael Leitner Dazhong Yang Martin Wolf 《Macromolecular Symposia》1995,98(1):269-283
Cationic polymerisation of 1, 4-diisopropenyl benzene, 1, 4-(2-chloro-isopropyl)benzene and related compounds yields soluble polymers with repeating units of indan. High performance polymers with indan units are available via nucleophilic substitution of halogenated aromatic monomers containing a central indan element, which are synthesized from 1, 1, 3-trimethyl-3-phenylindan via Friedel-Crafts-reaction with corresponding halogenated acyl- and sulfonyl chlorides. 相似文献
479.
Chenxi Zhai Yang Yu Yumei Zhu Jing Zhang Ying Zhong Jingjie Yeo Mingchao Wang 《Molecules (Basel, Switzerland)》2022,27(3)
Foaming effect strongly impacts the physical and mechanical properties of foam glass materials, but an understanding of its mechanism especially at the molecular level is still limited. In this study, the foaming effects of dextrin, a mixture of dextrin and carbon, and different carbon allotropes are investigated with respect to surface morphology as well as physical and mechanical properties, in which 1 wt.% carbon black is identified as an optimal choice for a well-balanced material property. More importantly, the different foaming effects are elucidated by all-atomistic molecular dynamics simulations with molecular-level insights into the structure–property relationships. The results show that smaller pores and more uniform pore structure benefit the mechanical properties of the foam glass samples. The foam glass samples show excellent chemical and thermal stability with 1 wt.% carbon as the foaming agent. Furthermore, the foaming effects of CaSO4 and Na2HPO4 are investigated, which both create more uniform pore structures. This work may inspire more systematic approaches to control foaming effect for customized engineering needs by establishing molecular-level structure–property–process relationships, thereby, leading to efficient production of foam glass materials with desired foaming effects. 相似文献
480.
Dong-Zhao Yang Zhen-Zhen Chen Mei Chi Ying-Ying Dong Shou-Zhi Pu Qi Sun 《Molecules (Basel, Switzerland)》2022,27(3)
5-Hydroxymethyl-2′-deoxycytidine (5hmdC) phosphoramidite and triphosphate are important building blocks in 5hmdC-containing DNA synthesis for epigenetic studies. However, efficient and practical methods for the synthesis of these compounds are still limited. The current research provides an intensively improved synthetic method that enables the preparation of commercially available cyanoethyl-protected 5hmdC phosphoramidite with an overall yield of 39% on 5 g scale. On the basis of facile and efficient accesses to cyanoethyl protected-5hmdU and 5hmdC intermediates, two efficient synthetic routes for 5hmdC triphosphate were also developed. 相似文献