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排序方式: 共有1115条查询结果,搜索用时 15 毫秒
1.
Liu Wei Zhao Fusheng Kong Meiling Yin Songfeng Wang Huiying Liu Xiaoying 《Fire Technology》2022,58(5):2811-2823
Fire Technology - The use of perfluorinated hexanone as a fire extinguishing agent for lithium-ion batteries (LIBs) has been steadily increasing in China in recent years. It successfully handles... 相似文献
2.
Meiling Shi Leqi Yao Junfeng Xu Chao Liang Yan Dong Qiyue Shao 《Journal of the American Ceramic Society》2021,104(7):3279-3288
Phosphors-converted LEDs (pc-LEDs) are excellent artificial light sources for indoor plant cultivation, in which the far-red-emitting component (700−780 nm) plays an important role in regulating the photomorphogenesis of plants. Accordingly, highly efficient and thermally stable far-red-emitting phosphors are indispensable for developing high-performance plant cultivation pc-LEDs. Herein, far-red-emitting YAl3(BO3)4:Cr3+ (YAB:Cr3+) phosphors were synthesized by solid-state reaction, and their photoluminescence characteristics, thermal quenching, quantum yield (QY), and application in pc-LEDs were systematically investigated. The YAB:Cr3+ phosphor has an intense broadband absorption to the blue light, simultaneously exhibiting the sharp-line 2E emission and the broadband 4 T2 emission of Cr3+ with a QY of ~86.7%. The far-red broadband emissions of YAB:Cr3+ centered at ~735 nm show a high resemblance to the active-state (PFR) absorption of plant phytochrome. Moreover, the YAB:Cr3+ phosphor shows the thermally enhanced luminescence at temperatures of 303−393 K and the near-zero thermal quenching up to 423 K. The anomalous thermal enhancement is attributed to the temperature-dependent repopulation between 2E and 4 T2 states. Finally, a pc-LED device was fabricated with the YAB:Cr3+ phosphor and blue chip, exhibiting the light out power of ~50.6 mW and energy conversion efficiency of ~17.4% at 100 mA drive current, respectively. The exceptional PL features including suitable excitation/emission wavelengths, suppressed thermal quenching and high QY make YAB:Cr3+ phosphors very promising for applications in plant growth pc-LEDs. 相似文献
3.
Sangmin Lee Biao Che Meiling Tai Wanzhao Li Shin-Hyun Kim 《Advanced functional materials》2021,31(42):2105477
Hydrogel shells that compartmentalize the water core from the aqueous surrounding provide molecular selectivity on size and charge in transmembrane transport. It is highly demanding to produce thin hydrogel shells to minimize diffusion length and maximize core volume. Here, internal osmosis in water-in-oil-in-water-in-oil (W/O/W/O) triple-emulsion droplets is used to produce thin hydrogel shells enclosing a large water core. The triple-emulsion droplets are prepared to have an ultrathin middle oil layer using a capillary microfluidic device. The innermost water droplet has a higher osmolarity than the outer water layer containing photopolymerizable hydrogel precursors, which pumps water from the outer layer to the core through the ultrathin oil layer by the osmosis. Therefore, the outer layer gets thinner and hydrogel precursors are enriched while the size of the triple-emulsion droplets remains unchanged. Through photopolymerization of precursors and phase transfer from oil to water, hydrogel shells enclosing water core are produced in the water environment; the oil layer is ruptured for molecular exchange through the shells. The thickness and composition of the hydrogel shells are precisely controllable by the osmotic conditions. The shells show a high permeation rate due to the thinness as well as controlled cut-off threshold of permeation for neutral and charged molecules. 相似文献
4.
Meiling He Yinzi Cheng Linli Shen Huiling Zhang Chenyang Shen Weidong Xiang Xiaojuan Liang 《Journal of the American Ceramic Society》2019,102(3):1090-1100
CsPbX3 (X = Cl, Br, I) perovskite quantum dots (QDs) represent bright and tunable photoluminescence, it is regrettable that the air instability and poor water resistant properties prevent their application in optoelectronic devices. At the same time, the toxicity of lead is also a major factor restricting its development. As a consequence, we demonstrate the partial replacement of Pb with Mn through conventional melt-quenching and heat-treatment method preparation of Mn-doped CsPb(Cl/Br)3 QD glass. Mn-doped CsPb(Cl/Br)3 QD glass exhibits high luminescent intensity like QDs. It is important that Mn-doped CsPb(Cl/Br)3 QD glass with Dual-Color maintained the same lattice structure like Mn-doped CsPb(Cl/Br)3 QDs, and highly homogeneous spectral characteristics of Mn luminescence. The intensity and position of this Mn-related emission are also tunable by altering the experimental parameters, such as the Pb-to-Mn feed ratio, annealing temperature. More importantly, the as-prepared orange Mn-doped CsPb(Cl/Br)3 QD glass was employed to fabricate white LEDs combined with a commercial Ce3+:Y3Al5O12 phosphor-in-glass (Ce-PiG) on top of a InGaN blue chip. And the constructed WLEDs generate a warm white with an optimal luminous efficacy (LE) of 67.00 lm/W, a high CRI of 81.4, and a low CCT of 4902 K. 相似文献
5.
6.
Safa Meraghni Labib Sadek Terrissa Meiling Yue Jian Ma Samir Jemei Noureddine Zerhouni 《International Journal of Hydrogen Energy》2021,46(2):2555-2564
Prognostics and health management of proton exchange membrane fuel cell (PEMFC) systems have driven increasing research attention in recent years as the durability of PEMFC stack remains as a technical barrier for its large-scale commercialization. To monitor the health state during PEMFC operation, digital twin (DT), as a smart manufacturing technique, is applied in this paper to establish an ensemble remaining useful life prediction system. A data-driven DT is constructed to integrate the physical knowledge of the system and a deep transfer learning model based on stacked denoising autoencoder is used to update the DT with online measurement. A case study with experimental PEMFC degradation data is presented where the proposed data-driven DT prognostics method has applied and reached a high prediction accuracy. Furthermore, the predicted results are proved to be less affected even with limited measurement data. 相似文献
7.
Zhang Beixian Liu Meiling Zhou Bo Liu Xingyi 《Multimedia Tools and Applications》2022,81(24):34263-34279
Multimedia Tools and Applications - Graph Convolutional Networks (GCNs) recently have been adopted in several feature representation studies for different classification tasks. While many of these... 相似文献
8.
A core-shell Pt/C@NCL300 catalyst with an accessible layer was designed to recover lost ORR activity and was constructed via a one-step self-assembly process in this paper. A thin porous layer derived from Nafion was first formed on the surface of Pt/C catalyst to create a shell. This first coating successfully separated the Nafion and Pt particles in the catalysts and reducing the negative impact of Nafion on ORR activity and enhancing the fuel cell performance. The newly fabricated Pt/C@NCL300 catalyst exhibited much higher specific activity than the original Pt/C catalyst in RDE tests under the same conditions and were comparable to the activity of Pt/C electrode without Nafion poisoning. Moreover, the fuel cell with Pt/C@NCL300 catalyst exhibited a higher power density without an obvious increase in proton transport and O2 transport resistance compared to that of a Pt/C fuel cell with a low Pt loading. This result indicates that coating the Pt/C catalyst with a layer accessible for oxygen and protons is a promising way to effectively promote Pt-based catalysts that work under normal operating conditions. 相似文献
9.
黑虎香葡萄属于鲜食、酿酒兼用品种,香气独特、抗逆性强。对转色期黑虎香葡萄果实喷施不同浓度脱落酸(ABA),研究其对葡萄酒品质的影响。结果表明,喷施500 mg/L ABA处理效果最好,显著提高黑虎香葡萄酒酒精度、干浸出物、花色苷和总酚含量,显著降低酸含量(P<0.05);显著增加黑虎香葡萄酒萜烯类、醇类和醛酮类等香气物质含量(P<0.05),含量影响较大的香气成分为乙酸乙酯、乙酸苯乙酯、苯乙醇、壬醇、戊二酮、香叶基丙酮、乙缩醛、香茅醇和香叶醇。 相似文献
10.