14 research outputs found
New insights into organic light emitting devices: photophysics, recombination, and out coupling
Efficacy of mobile-based educational intervention using Instructional Systems Design in promoting preventive behaviors for sexually transmitted infections among Iranian women: a randomized controlled trial
Abstract Background Women who are sexually active are at risk of sexually transmitted infections (STIs), which can cause serious difficulties for their reproductive health. However, despite the high global burden of STIs, most infections are preventable with education for behavioral change. The purpose of this study is to investigate the Efficacy of Mobile-Based Educational Intervention Using Instructional Systems Design in Promoting Preventive Behaviors for Sexually Transmitted Infections among Iranian Women. Methods This randomized controlled trial aimed at promoting preventive behaviors related to STIs in Iranian women with an educational intervention based on the Instructional Systems Design (ISD) in 2022. The participants in this study were recruited from a single center, specifically the Health House No. 3 located in District 11 of Tehran Municipality. Two instruments were used in the present study: a) a valid scale titled: “Four-Scale of STI Preventive Behaviors”, and b) a researcher-made Questionnaire titled: “Social perception affecting sexually transmitted infections (SOPESTI)”. These tools contain 8 demographic items and specific questions with a total of 68 five-point Likert scales. The intervention comprised three phases: a pre-test (baseline), a training program, and two follow-up assessments (4 and 12 weeks after the start of the training program). The experimental group received education through a mobile app, while the control group received no intervention. SPSS v.26 was used, with a significance level of P < 0.05. The chi-square test, Fisher’s exact test, independent t-tests, analysis of covariance (ANCOVA), and repeated measures ANOVA were used to analyze the data. Results A total of 80 women, with a mean age of 36.524 ± 6.91 (experiment group) and 34.78 ± 8.20 (control group), respectively, participated in the trial. The study revealed a statistically significant difference in the mean score for eight domains, including STIs Knowledge, STIs Vulnerability, STIs Preventive Self-efficacy, STIs Prevention intentions, STIs Perceived social exclusion, STIs Perceived cognitive barriers, STIs Perceived social support, and STIs Perceived risks in the experiment group following the intervention compared to before the intervention (p < 0.05). Conclusion The results of this study showed that a mobile-based educational intervention based on the ISD model had a significant effect on the preventive behaviors of STIs in Iranian women. These results highlight the potential benefit of mobile health in enhancing reproductive health. Trial registration ClinicalTrials.gov IRCT20200602047638N1. Registered on 22 May 2021 with the IRCTID, V1.0. https://www.irct.ir/trial/5563
Hybrid Area-Emitting Transistors: Solution Processable and with High Aperture Ratios.
Area emission is realized in all-solution-processed hybrid light-emitting transistors (HLETs). A new HLET design is presented with increased aperture ratio, and optical and electrical characteristics are shown
Semitransparent and Low-Voltage Operating Organic Light-Emitting Field-Effect Transistors Processed at Low Temperatures
A see-through organic light emitting field-effect transistor (LEFET) is realized by using a highly transparent, high mobility material. Low voltage operated LEFETs with increased optical and electrical characteristics are shown
Hybrid area emitting transistors: solution processable and with high aperture ratios: supplementary information
1. MATERIALS AND METHODS Materials used in this study – Table S1 ZTO morphology and electrical characteristics – Figure S1, S2 2. OPTICAL AND ELECTRICAL PROPERTIES OF THE ORGANIC EMISSIVE MATERIALS Molecular structures of the emissive materials – Figure S3 EL and PL of the emissive materials – Figure S4 CIE Coordinates of emissive materials – Figure S5 Area Emission in SY, F8BT and PFO interdigitated devices – Figure S6 Device schematics, energy diagrams and working principles – Figure S7 Calculation of HOMO/LUMO for SY, F8BT and PFO – Figure S8 and Table S2 3. DEVICE CHARACTERISTICS Measurement of ZTO and ZTO/PEIE workfunction using KPFM – Figure S9 HLETs (control) using F8BT and PFO as the active layer – Figure S10, S11 Transmission spectrum for drain electrode – Figure S12 Comparison with literature values – Table S
Charge transport and recombination in heterostructure organic light emitting transistors
Light-emitting field effect transistors (LEFETs) are a class of organic optoelectronic device capable of simultaneously delivering the electrical switching characteristics of a transistor and the light emission of a diode. We report on the temperature dependence of the charge transport and emissive properties in a model organic heterostructure LEFET system from 300 K to 135 K. We study parameters such as carrier mobility, brightness, and external quantum efficiency (EQE), and observe clear thermally activated behaviour for transport and injection. Overall, the EQE increases with decreasing temperature and conversely the brightness decreases. These contrary effects can be explained by a higher recombination efficiency occurring at lower temperatures, and this insight delivers new knowledge concerning the optimisation of both the transport and emissive properties in LEFETs
Synthesis and properties of pyrrolo[3,2-b]pyrrole-1,4-diones (isoDPP) derivatives
The synthesis of three pyrrolo[3,2-b] pyrrole-1,4-dione (isoDPP) derivatives is described, namely 1,3,4,6-tetraphenylpyrrolo[3,2-b] pyrrole-2,5(1H, 4H)-dione 2, 1,4-diphenyl-3,6-di(thiophen-2-yl) pyrrolo[3,2-b]-pyrrole-2,5(1H, 4H)-dione 3, and 1,4-bis(4-(hexyloxy) phenyl)-3,6-di(thiophen-2-yl) pyrrolo[3,2-b] pyrrole-2,5(1H, 4H)-dione 7 in which the molecular structures differ in the aromatic ring (phenyl or thiophene) attached to the nitrogen atom. Thin films of 2, 3, and 7 could be formed by evaporation under vacuum. In the case of 2 and 3 GIWAXS measurements showed that the film structural ordering was similar to that measured in single crystals. In contrast GIWAXS showed that 7 had features associated with liquid crystalline materials. Time dependent density functional theory (TDDFT) calculations predicted that the transition between the lowest energy singlet excitation (S-1) and the ground state (S-0) would be optically forbidden due to the centrosymmetric geometries of compounds. Photophysical measurements showed that the compounds were weakly luminescent, with low radiative rates in solution of order 10(6) s(-1), which are consistent with the TDDFT predictions. Furthermore, photoinduced absorption (PIA) spectroscopy showed that there is a long-lived low energy state, which has been assigned as a triplet and provides a further non-radiative decay pathway for the excited state
Effect of capping group on the properties of non-polymeric diketopyrrolopyrroles for solution-processed bulk heterojunction solar cells
Solution-processable non-polymeric organic semiconductors are attractive for opto-electronic applications due to their relatively simple synthetic reproducibility and characterization, and enhanced capability for fine-tuning of their properties. We report the synthesis, charge transport, photophysics, and photovoltaic properties of three non-polymeric materials based upon bisarylthiophenyl diketopyrrolopyrrole [DPP(ThAr)(2)]. The DPP(ThAr)(2) molecules are comprised of solubilizing alkyl groups, 2-ethylhexyl (for 1a) and 2-octyldodecyl (for 1b and 2), which are capped with "electron accepting" moieties -fluorenone (1) or benzothiadiazole (2). While the materials could be prepared under standard SuzukiMiyaura cross-coupling conditions, a simple direct arylation afforded 2 and 1b in good yields. We found 1a with a short alkyl chain lacked sufficient solubility for solution processing but 1b and 2 are solution processable and form good quality films. All three materials exhibited ambipolar charge transport in field effect transistors, with 1b showing balanced charge mobilities of about 10(-3) cm(2) V-1 s(-1). Bulk heterojunction solar cells of 1b or 2 with PC71BM were found to have high opencircuit voltages (up to 0.9 V) with power conversion efficiencies of up to 4.5% and 2.6%, respectively. (C) 2017 Elsevier B.V. All rights reserved