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111.
Enhanced Electroluminescence from Organic Light‐Emitting Diodes with an Organic–Inorganic Perovskite Host Layer 下载免费PDF全文
Toshinori Matsushima Chuanjiang Qin Kenichi Goushi Fatima Bencheikh Takeshi Komino Matthew Leyden Atula S. D. Sandanayaka Chihaya Adachi 《Advanced materials (Deerfield Beach, Fla.)》2018,30(38)
The development of host materials with high performance is essential for fabrication of efficient and stable organic light‐emitting diodes (OLEDs). Although host materials used in OLEDs are typically organics, in this study, it is shown that the organic–inorganic perovskite CH3NH3PbCl3 (MAPbCl3) can be used as a host layer for OLEDs. Vacuum‐evaporated MAPbCl3 films have a wide band gap of about 3 eV and very high and relatively balanced hole and electron mobilities, which are suitable for the host material. Photoluminescence and electroluminescence take place through energy transfer from MAPbCl3 to an organic emitter in films. Incorporation of an MAPbCl3 host layer into OLEDs leads to a reduction of driving voltage and enhancement of external quantum efficiency as compared to devices with a conventional organic host layer. Additionally, OLEDs with an MAPbCl3 host layer demonstrate very good operational stability under continuous current operation. These results can be extensively applied to organic‐ and perovskite‐based optoelectronics. 相似文献
112.
Brahim Fady Jaouad Terhzaz Abdelwahed Tribak Fatima Riouch Angel Mediavilla 《国际射频与微波计算机辅助工程杂志》2019,29(11)
This article presents a novel low‐cost integrated multiband antenna design customized for navigation media applications. The distinctive feature of the design consists in using a broadband planar dipole with four arms and a miniaturized feeding‐point, easy to deploy inside the tracking devices, and cost‐effective for supply chain industry. The article first introduces the main challenges and the benefits of miniaturizing antennas for supply‐chain and particularly for navigation media system which is the case‐study. Further the parametric study and final dimensions of the design and the simulation results are discussed. The proposed design is fabricated and the measurements of the radiation pattern and the return loss are performed proving that the antenna with maximum gain up to 10 dBi and S11 up to ?30 dB, exhibits excellent performance for all the frequencies required in the navigation media systems such as 1.6, 1.8, 2.3, 2.4, 2.6, 3.6, and 5.8 GHz. The proposed design was implemented and tested inside a tracking device mounted on a vehicle and compared with existing commercial antennas. This study showed that the proposed antenna is suitable for tracking devices as it is miniaturized for internal integration and it has better 4G and GPS signal detection and low power consumption comparatively with existing commercial antennas. 相似文献
113.
Rachid Lajouad Abdelmounime El Magri Abderrahim El Fadili Fatima‐Zahra Chaoui Fouad Giri 《Asian journal of control》2015,17(4):1365-1376
This paper presents a theoretical framework for adaptive control of a wind energy conversion system (WECS), involving a squirrel cage induction generator (SIG) connected with an AC/DC/AC IGBT‐based PWM converter. A multi‐loop nonlinear controller is designed to meet two main control objectives, i.e., (i) speed reference optimization in order to extract a maximum wind energy whatever the wind speed, and (ii) power factor correction (PFC) to avoid net harmonic pollution. These objectives must be achieved despite the mechanical parameters uncertainty. First, a nonlinear model of the whole controlled system is developed within the Park coordinates. Then, a multi‐loop nonlinear controller is synthesized using the adaptive backstepping design. A formal analysis based on Lyapunov stability is carried out to describe the control system performances. In addition to closed‐loop global asymptotic stability, it is proven that all control objectives (induction generator speed tracking, rotor flux regulation, DC link voltage regulation and unitary power factor) are asymptotically achieved. 相似文献
114.
Fatima Pardo-Tarifa Saúl Cabrera Margarita Sanchez-Dominguez Magali Boutonnet 《International Journal of Hydrogen Energy》2017,42(15):9754-9765
The effect of ceria promotion on the performance of Co/Al2O3 catalyst was evaluated in a high pressure fixed bed reactor for Fischer–Tropsch (FT) synthesis at close industrial conditions. Ce–Al2O3 supports with a molar ratio of Al/Ce = 8 were prepared by two different methods: one by co-precipitation of cerium and aluminum precursors in water-in-oil microemulsion and the other one by aqueous impregnation of cerium nitrate on commercial alumina. These supports, together with the unmodified alumina carrier, were used to prepare four cobalt-based catalysts. These catalysts were characterized by XRD, SEM, EDX, TEM, N2 adsorption/desorption, TPR and chemisorption techniques. The results show that the presence of CeO2 on the surface of the support favors the reducibility of cobalt oxides with a shift down in reduction temperature of about 70 °C. The catalytic evaluation of the catalysts revealed that cerium addition by impregnation increases the activity and selectivity to C5+ catalyst in FTS. The catalyst synthetized by microemulsion show lower catalytic performance. Nevertheless, the catalytic property of this material can be improved by increasing the crystalline micro-domains size of CeO2. 相似文献
115.
Maria De Fatima Somerlate Barbosa Daison Olzany Silva Adão José Rezende Pinheiro Walter Vieira Guimarães Arnaldo Chaer Borges 《Journal of dairy science》1985,68(7):1618-1623
Two strains of Kluyveromyces fragilis (145 and 276) and one of Kluyveromyces lactis were tested for their abilities to produce beta-D-galactosidase in cheese whey. Kluyveromyces fragilis 145 was selected for its higher beta-D-galactosidase activity per cell at the end of the exponential growth phase.Addition of ammonium sulfate (.3%) and yeast extract (.1%) to the deproteinized cheese whey increased cell mass and enzyme yield.Addition of 3% lactose did not affect beta-D-galactosidase activity per cell, which responded positively to a reduction in aeration from 1 to .25 air volume/medium volume/min.The harvested yeast cells were ethanol- and acetone-permeabilized to enhance lactose hydrolysis by beta-D-galactosidase. 相似文献
116.
Alexis Espinal Michael W. Epperly Amitava Mukherjee Renee Fisher Donna Shields Hong Wang M. Saiful Huq Diala Fatima Hamade Anda M. Vlad Lan Coffman Ronald Buckanovich Jian Yu Brian J. Leibowitz Jan-Peter van Pijkeren Ravi B. Patel Donna Stolz Simon Watkins Asim Ejaz Joel S. Greenberger 《International journal of molecular sciences》2022,23(10)
(1) Background: The systemic administration of therapeutic agents to the intestine including cytokines, such as Interleukin-22 (IL-22), is compromised by damage to the microvasculature 24 hrs after total body irradiation (TBI). At that time, there is significant death of intestinal microvascular endothelial cells and destruction of the lamina propria, which limits drug delivery through the circulation, thus reducing the capacity of therapeutics to stabilize the numbers of Lgr5+ intestinal crypt stem cells and their progeny, and improve survival. By its direct action on intestinal stem cells and their villus regeneration capacity, IL-22 is both an ionizing irradiation protector and mitigator. (2) Methods: To improve delivery of IL-22 to the irradiated intestine, we gavaged Lactobacillus-reuteri as a platform for the second-generation probiotic Lactobacillus-reuteri-Interleukin-22 (LR-IL-22). (3) Results: There was effective radiation mitigation by gavage of LR-IL-22 at 24 h after intestinal irradiation. Multiple biomarkers of radiation damage to the intestine, immune system and bone marrow were improved by LR-IL-22 compared to the gavage of control LR or intraperitoneal injection of IL-22 protein. (4) Conclusions: Oral administration of LR-IL-22 is an effective protector and mitigator of intestinal irradiation damage. 相似文献
117.
118.
Stephanie Eichhorn Angelika Hrschlger Markus Steiner Josef Laimer Bettina M Jensen Serge A Versteeg Isabel Pablos Peter Briza Laurian Jongejan Neil Rigby Juan A Asturias Antonio Portols Montserrat Fernandez‐Rivas Nikolaos G Papadopoulos Adriano Mari Lars K Poulsen Peter Lackner Ronald van Ree Fatima Ferreira Gabriele Gadermaier 《Molecular nutrition & food research》2019,63(18)
119.
Aghiles Hammas Gisèle Lecomte-Nana Imane Daou Fatima Zibouche 《International Journal of Applied Ceramic Technology》2020,17(5):2265-2276
The present work aims at studying the effect of the sintering temperature and magnesite addition on the structure and final properties of silicate ceramics tapes. A kaolinitic clay from Algeria was selected and mixed with different magnesite contents (≤12 mass%). Tape casting process was used to produce the green tapes in an aqueous system with optimized amount of surfactants. The green tapes were fired from 1000°C to 1200°C using a dwelling time of 30 minutes. The effect of the dwelling time was investigated for a firing temperature of 1200°C namely: 30 minutes, 1 hour 30 minutes and 3 hours for samples with 6 and 12 mass% of magnesite. Regarding firing conditions, crystalline phases, thermal conductivity, porosity, and flexural strength were analyzed. The results showed that increasing the sintering temperature to 1200°C tended to significantly decrease the total porosity of samples, which led to the improvement of the stress to rupture values. Specimens with 6 and 12 mass% sintered during 3 hours exhibited highest stress to rupture values (≈117 MPa) and lowest thermal conductivity (<0.2 W.m−1.K−1) and moderate open porosity (27%). The as-obtained ceramics appeared promising for further utilization in refractory industry, thanks to the presence of both cordierite and mullite phases. 相似文献
120.
Kaniz Fatima Sultana So Young Lee Ji-Eun Lee Joobeom Seo Shim Sung Lee 《Inorganic chemistry communications》2007,10(12):1496-1500
Two 20-membered penta- and hexadentate macrocycles containing one or two pyridine subunits, namely [20]aneNO2S2 (L1) and [20]aneN2O2S2 (L2), have been synthesized. Reaction of L1 with silver(I) nitrate afforded a unique 2:2 (M:L) disilver(I) complex [μ2-Ag2(L1)2](NO3)2 (1) in which two four-coordinate Ag atoms bridge two ligands to form a cyclic dimer. In contrast, an endo-dentate 1:1 monosilver(I) complexes [AgL2]X; [X = ClO4 (2) or PF6 (3)] which show isomorphous structures were obtained from the reactions of L2 with silver(I) salts. 相似文献