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171.
Marta Martínez-Abadía Aurelio Mateo-Alonso 《Advanced materials (Deerfield Beach, Fla.)》2020,32(40):2002366
The ability to design and synthesize monomers can affect fundamental aspects in 2D covalent organic frameworks, such as dimensionality, topology, and pore size. Besides this, the structure of the monomers can also affect interlayer interactions, which provide an additional means to influence crystallinity, layer arrangement, interlayer distances, and exfoliability. Herein, some of the effects that the structure of monomers can have on the interlayer interactions in 2D covalent organic frameworks and related materials are illustrated. 相似文献
172.
In this paper, we investigated the effect of PEI cathode interlayer on the work function and the interface resistance of ITO electrode in the inverted polymer solar cells (PSCs) based on PBDTTT-C-T:PC70BM. It is found that a very thin layer of PEI (⩽5.5 nm), either linear PEI (l-PEI) or branched PEI (b-PEI) with different molecular weights, is enough to lower the work function of the ITO electrode and to enhance the photovoltaic performance of the devices. The champion power conversion efficiency (PCE) of the devices with the PEI cathode interlayer is 7.84%, more than doubled of that without the interlayer. However, a thicker PEI interlayer (⩾10 nm) results in abrupt decrease of the PCEs due to the increase of the resistance. Interestingly, for the thicker interlayers, the l-PEI shows high photovoltaic performance than that of b-PEI, which can also be explained by their difference in the resistances. This work supplies an insight into the function of PEI cathode interlayer on improving the work function and resistance of ITO electrode in the inverted PSCs, and provides some instructions on the future design of interlayer materials in PSCs. 相似文献
173.
Two star-shaped oligofluorenes with hexakis(fluoren-2-yl)benzene as core are designed and synthesized, namely Tn0 and Tn1. Diethylamino groups are attached to the side chain of fluorene units of Tn0 and Tn1 and enable them alcohol solubility, additional hydrophobic nhexyl chains are grafted on the π-extended fluorene arms of Tn1. Power conversion efficiency (PCE) as high as 8.62% and 8.80% are achieved when utilizing Tn0 and Tn1 as cathode interlayers in inverted polymer solar cells, respectively. The work function of ITO effectively decreased by introducing interlayer, resulting in high Voc of the device, besides, the wetting properties of the interlayers can be tuned by modifying the oligofluorenes with π-extended structure, and the more hydrophobic interlayer will benefit the device performance with enhanced Jsc and FF. 相似文献
174.
Cheng-Che Tsai Wu-Han Liao Sheng-Yuan Chu Cheng-Shong Hong Mei-Chieh Yu Yun-You Lin Zhi-Yuan Wei 《Journal of the European Ceramic Society》2021,41(4):2472-2481
Multilayer piezoelectric ceramics must be sintered in a reducing atmosphere, preventing oxidation of the inner base metal. Plate-like textured (Ba, Ca)(Ti, Sn, Hf)O3 ceramics with a <001> preferred orientation were successfully developed at a low oxygen partial pressure (PO2:10?8 atm) using a BaTiO3 (BT) template with sintering temperatures < 1300 °C, which is beneficial for multilayer applications using base metal co-firing with ceramics. When adding the 3 wt% BT template, the proposed samples had a Lottgering factor of 84 %, piezoelectric coefficients d33 = 324 pC/N, -d31 = 122 (pC/N), and Qm = 452, and the strain values increased from 0.07 % for the randomly oriented ceramics to 0.115 % at 20 kV/cm for the textured ceramics, confirming that the texturing behavior assisted the grain growth and improved both the soft and hard behaviors and insulation resistance of the proposed lead-free ceramics. These findings make a significant contribution to the production of high-power piezoelectric components. 相似文献
175.
Wei Wang Xiaojun Wei Chuanshen Wang Wencai Zhou Bailin Zhu Chongjie Wang Linfei Liu 《Ceramics International》2021,47(3):3548-3552
Using the magnetic sputtering technique, the SnO2/Ag/SnO2 tri-layer transparent films were fabricated on float glasses successfully. Compared with the commercial FTO (F-doped SnO2) film, the SnO2/Ag/SnO2 tri-layer films have higher visible-light transmittance and better conductivity. The total thickness of the SnO2/Ag/SnO2 films is one third of the commercial FTO film leading to the high visible-light transmittance. The high carrier concentration of the SnO2/Ag/SnO2 films contributes to the tri-layer films’ low resistivity. In addition, to further improve the performance of the SnO2/Ag/SnO2 tri-layer films, samples were annealed under different temperatures. The results illustrate that the lowest sheet resistance (5.92 Ω/sq) and the highest visible-light transmittance (87.0%) were obtained after annealing at 200 °C. Furthermore, the thermal stability of the films could be enhanced by a multi-step annealing process due to the recrystallization effect. 相似文献
176.
Hanqin Liang Kaihui Zuo Yongfeng Xia Dongxu Yao Jinwei Yin Yuping Zeng 《Ceramics International》2018,44(5):4824-4828
Lu-Al-Si-O-N tapes with different thickness were used to join gas pressure sintered Si3N4 ceramics. The microstructure of the joints and the influences of the joint thickness and joining temperature on the bonding strength of the as-joined Si3N4 ceramics have been investigated. The highest bonding strength about ~ 300 MPa of the joined specimens was achieved by using 450 µm interlayer at 1450 °C. The existence of Si3N4 nanowires was beneficial for the improvement of the bonding strength by interweaving the oxynitride glass matrix in the joint region. 相似文献
177.
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179.
Water sorption and cooking time of red kidney beans (Phaseolus vulgaris L.): part I – Effect of freezing and drying conditions on water sorption and cooking time 下载免费PDF全文
Fuji Jian Digvir S. Jayas Paul G. Fields Noel D.G. White 《International Journal of Food Science & Technology》2017,52(9):2031-2039
Water sorption and cooking time of kidney beans were determined. The beans were manually harvested at 19.2 ± 0.1% moisture content and stored at ?20 and ?10 °C for about half a year. The beans were further dried at 30, 40 and 50 °C inside a thin‐layer drier for 7.5 h or under room conditions for 4 week. The freezing storage temperature before the beans were dried did not influence their cooking time and water sorption. The saturated kernel volumes decreased approximately 7% after drying. The beans decreased their sphericity during water sorption and had a larger swelling ratio in the thickness direction than in other directions. Lower initial moisture content, especially with a higher drying temperature, decreased water sorptivity and resulted in higher percentage of uncooked kernels if the beans were not soaked before cooking. However, there was no relationship between initial moisture content and uncooked percentage if the beans were soaked before cooking. High drying temperature resulted in hard‐to‐cook (HTC) phenomenon. 相似文献
180.
《中国有色金属学会会刊》2021,31(8):2277-2286
The effects of laser parameters and interlayer material on the microstructure and properties of the welded joint between 6061 aluminum alloy and stainless steel were studied. The results show that the density and microstructure of the welded joint can be optimized by changing the laser power with 0.05 mm Cu foil and 0.1 mm Ni foil as interlayer. A large number of new Cu–Al binary phases were found near the aluminum alloy, which effectively inhibited the formation of the binary brittle phase of Fe–Al. The maximum shear force of 1350.96 N was obtained with laser power of 2200 W. The shear force of the welded joint increased to 1754.73 N when the thickness of the Cu foil thickness changed to 0.02 mm. 相似文献