SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Alshehri Saad M.) "

Sökning: WFRF:(Alshehri Saad M.)

  • Resultat 1-8 av 8
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Tabiri, S, et al. (författare)
  • 2021
  • swepub:Mat__t
  •  
2.
  • Bravo, L, et al. (författare)
  • 2021
  • swepub:Mat__t
  •  
3.
  •  
4.
  •  
5.
  • 2019
  • Tidskriftsartikel (refereegranskat)
  •  
6.
  • Abouzid, Mohamed, et al. (författare)
  • Investigating the current environmental situation in the Middle East and North Africa (MENA) region during the third wave of COVID-19 pandemic : urban vs. rural context
  • 2022
  • Ingår i: BMC Public Health. - : Springer Nature. - 1471-2458. ; 22:1
  • Tidskriftsartikel (refereegranskat)abstract
    • BackgroundCoronavirus 2019 (COVID-19) pandemic led to a massive global socio-economic tragedy that has impacted the ecosystem. This paper aims to contextualize urban and rural environmental situations during the COVID-19 pandemic in the Middle East and North Africa (MENA) Region.ResultsAn online survey was conducted, 6770 participants were included in the final analysis, and 64% were females. The majority of the participants were urban citizens (74%). Over 50% of the urban residents significantly (p < 0.001) reported a reduction in noise, gathering in tourist areas, and gathering in malls and restaurants. Concerning the pollutants, most urban and rural areas have reported an increase in masks thrown in streets (69.49% vs. 73.22%, resp.; p = 0.003). Plastic bags and hospital waste also increased significantly with the same p-value of < 0.001 in urban areas compared with rural ones. The multifactorial logistic model for urban resident predictors achieved acceptable discrimination (AUROC = 0.633) according to age, crowdedness, noise and few pollutants.ConclusionThe COVID-19 pandemic had a beneficial impact on the environment and at the same time, various challenges regarding plastic and medical wastes are rising which requires environmental interventions.
  •  
7.
  • Shi, Changsheng, et al. (författare)
  • Managing excitons for high performance hybrid white organic light-emitting diodes by using a simple planar heterojunction interlayer
  • 2018
  • Ingår i: Applied Physics Letters. - : AMER INST PHYSICS. - 0003-6951 .- 1077-3118. ; 112:2
  • Tidskriftsartikel (refereegranskat)abstract
    • High performance hybrid white organic light-emitting diodes (WOLEDs) were fabricated by inserting a planar heterojunction interlayer between the fluorescent and phosphorescent emitting layers (EMLs). The maximum external quantum efficiency (EQE) of 19.3%, current efficiency of 57.1 cdA(-1), and power efficiency (PE) of 66.2 mu m W-1 were achieved in the optimized device without any light extraction enhancement. At the luminance of 1000 cdm(-2), the EQE and PE remained as high as 18.9% and 60 mu m W-1, respectively, showing the reduced efficiency-roll. In order to disclose the reason for such high performance, the distribution of excitons was analyzed by using ultra-thin fluorescent and phosphorescent layers as sensors. It was found that the heterojunction interlayer can efficiently separate the singlet and triplet excitons, preventing the triplet excitons from being quenched by the fluorescent emitter. The introduction of the heterojunction interlayer between the fluorescent and phosphorescent EMLs should offer a simple and efficient route to fabricate the high performance hybrid WOLEDs. Published by AIP Publishing.
  •  
8.
  • Wu, Zhongbin, et al. (författare)
  • Achieving Extreme Utilization of Excitons by an Efficient Sandwich-Type Emissive Layer Architecture for Reduced Efficiency Roll-Off and Improved Operational Stability in Organic Light-Emitting Diodes
  • 2016
  • Ingår i: ACS Applied Materials and Interfaces. - : American Chemical Society (ACS). - 1944-8244 .- 1944-8252. ; 8:5, s. 3150-3159
  • Tidskriftsartikel (refereegranskat)abstract
    • It has been demonstrated that the efficiency roll-off is generally caused by the accumulation of excitons or charge carriers, which is intimately related to the emissive layer (EML) architecture in organic light-emitting diodes (OLEDs). In this article, an efficient sandwich-type EML structure with a mixed-host EML sandwiched between two single-host EMLs was designed to eliminate this accumulation, thus simultaneously achieving high efficiency, low efficiency roll-off and good operational stability in the resulting OLEDs. The devices show excellent electroluminescence performances, realizing a maximum external quantum efficiency (EQE) of 24.6% with a maximum power efficiency of 105.6 lm W-1 and a maximum current efficiency of 93.5 cd A(-1). At the high brightness of 5 000 cd m(-2), they still remain as high as 23.3%, 71.1 lm W-1, and 88.3 cd A(-1), respectively. And, the device'lifetime is up to 2000 h at initial luminance of 1000 cd m(-2), which is significantly higher than that of compared devices with conventional EML structures. The improvement mechanism is systematically studied by the dependence of the exciton distribution in EML and the exciton quenching processes. It can be seen that the utilization of the efficient sandwich-type EML broadens the recombination zone width, thus greatly reducing the exciton quenching and increasing the probability of the exciton recombination. It is believed that the design concept, provides a new avenue for us to achieve high-performance OLEDs.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-8 av 8

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy