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This study was carried out in three seasons 2019, 2020 and 2021 to examine the effect of spraying Pota crastal or Vast trivolium compounds each at 0.1% either once, twice or thrice on growth and vine nutritional status of Superior grapevines grown under El- Minia region.Application of Pota crastal or Vast trivolium compounds once, twice or thrice each at 0.1% was very effective in enhancing main shoot length, leaf area, wood ripening coefficient, pruning wood weight/ vine, chlorophylls a , b , total chlorophylls, total carotenoids, N, P, K, Mg (as %) Fe, Mn and Zn ( as ppm) of superior grapevines over the control treatment.Using vast trivolium compound was favourable in enhancing some characteristics of vegetative growth and vine nutritional status rather than application of Pota crastal compound. The improvement in the growth characteristics and vine nutritional status was associated with an increase in the number of spraying times from one to three times. The best results with regard to character growth and vine nutritional status of superior grapevines grown under El- Minia region were observed due to treating the vines three times during each season at growth start, just after berry setting and at one month later intervals with vast trivolium compound at 0.1%.

The study reports two pairs of chiral multi‐resonant thermally activated delayed fluorescence (MR‐TADF) materials PCP‐DiKTa and Czp‐DiKTa by decorating a known MR‐TADF core, DiKTa, with different [2.2]paracyclophane (PCP) based planar chiral groups. PCP‐DiKTa shows narrow sky‐blue emission with a full width at half maximum (FWHM) of 44 nm, while the emission of Czp‐DiKTa is slightly broader with a FWHM of 66 nm and redshifted. Both emitters show high photoluminescence quantum yields of 93 and 99% for PCP‐DiKTa and Czp‐DiKTa, respectively. Enantiomerically pure samples of both compounds show chiroptical properties in the ground state while only Czp‐DiKTa exhibits chiroptical activity in the excited state, with dissymmetry factors (|gPL|) of 4 × 10−4. Organic light‐emitting diodes (OLEDs) with PCP‐DiKTa and Czp‐DiKTa show maximum external quantum efficiencies (EQEmax) of 25.7 and 29.2%, with λEL of 489 and 518 nm, and FWHMs of 53 and 69 nm, respectively. These EQEmax values are higher than those of other reported devices employing PCP‐based D‐A type emitters. This work demonstrates that the PCP moiety is not only a powerful building block to develop planar chiral emitters but one that is compatible with the fabrication of high efficiency devices. [ABSTRACT FROM AUTHOR]

The prototypical example of a (cyclo)phane, [2.2]paracyclophane (PCP), has proven to be a versatile stereogenic moiety within the design of circularly polarized thermally activated delayed fluorescence (CP‐TADF) emitters; however, the exploration of other cyclophanes within CP‐TADF emitter design has been largely neglected. Here, a comparative study of the photophysical and optoelectronic properties of two cyclophane emitters, (1,7)tBuCzpPhTrz and its isomer (1,4)tBuCzpPhTrz, is presented. The carbazolophane‐triazine compound (1,7)tBuCzpPhTrz, obtained via an unprecedented intramolecular rearrangement, is the first example of a planar chiral TADF emitter deviating from the PCP scaffold. Significant geometrical change of the enclosed carbazole in (1,7)tBuCzp results in an attenuation of the donor strength, while the merits of rigidity and steric bulk remain. In particular, the full width at half maximum (FWHM) of the photoluminescence spectrum in toluene of (1,7)tBuCzpPhTrz is reduced by 34% and blue‐shifted by 20 nm compared to that of (1,4)tBuCzpPhTrz. In doped films, the compounds reach high photoluminescence quantum yields (ΦPL) of 91 and 81%, respectively. The chiroptical properties reveal dissymmetry factors |gPL| of up to 5 × 10−4. These results demonstrate the impact of the cyclophane for the development of CP‐TADF materials and add to the currently limited scope of available planar chiral donors. [ABSTRACT FROM AUTHOR]

Multiresonant thermally activated delayed fluorescence (MR‐TADF) emitters have been the focus of extensive design efforts as they are recognized to show bright, narrowband emission, which makes them very appealing for display applications. However, the planar geometry and relatively large singlet–triplet energy gap lead to, respectively, severe aggregation‐caused quenching (ACQ) and slow reverse intersystem crossing (RISC). Here, a design strategy is proposed to address both issues. Two MR‐TADF emitters triphenylphosphine oxide (TPPO)‐tBu‐DiKTa and triphenylamine (TPA)‐tBu‐DiKTa have been synthesized. Twisted ortho‐substituted groups help increase the intermolecular distance and largely suppress the ACQ. In addition, the contributions from intermolecular charge transfer states in the case of TPA‐tBu‐DiKTa help to accelerate RISC. The organic light‐emitting diodes (OLEDs) with TPPO‐tBu‐DiKTa and TPA‐tBu‐DiKTa exhibit high maximum external quantum efficiencies (EQEmax) of 24.4% and 31.0%, respectively. Notably, the device with 25 wt% TPA‐tBu‐DiKTa showed both high EQEmax of 28.0% and reduced efficiency roll‐off (19.9% EQE at 1000 cd m−2) compared to the device with 5 wt% emitter (31.0% EQEmax and 11.0% EQE at 1000 cd m−2). The new emitters were also introduced into single‐layer light‐emitting electrochemical cells (LECs), equipped with air‐stable electrodes. The LEC containing TPA‐tBu‐DiKTa dispersed at 0.5 wt% in a matrix comprising a mobility‐balanced blend‐host and an ionic liquid electrolyte delivered blue luminance with an EQEmax of 2.6% at 425 cd m−2. The high efficiencies of the OLEDs and LECs with TPA‐tBu‐DiKTa illustrate the potential for improving device performance when the DiKTa core is decorated with twisted bulky donors. [ABSTRACT FROM AUTHOR]

Some applications of organic light‐emitting diodes (OLEDs) require large area, high light output, and high uniformity. It is difficult to achieve these attributes simultaneously because of voltage drops in the contacts, which cannot easily satisfy high optical transparency and electrical conductivity simultaneously. In large area OLEDs, thin electrodes with high sheet resistance induce voltage drops across the devices, leading to non‐uniform distribution of light. However, thick electrodes with low sheet resistance decrease the light output due to low transmittance. To overcome this trade‐off, a multilayer hybrid electrode based on Ag (20 nm)/WO3/Ag (20 nm)/WO3 is designed to obtain high electrical conductance with low optical loss. Compared to conventional devices using a single Ag (40 nm) top electrode, there is a considerable increase in the external quantum efficiency (EQE) of the device using this electrode (from 11.5% to 25.5% at 1000 cd m−2), while maintaining similar sheet resistance. In addition, a large area (≈57 cm2) OLED with the hybrid electrode demonstrates a luminance uniformity of 77% as compared to a device using single silver electrode with uniformity of 66%. Therefore, the proposed Ag/WO3/Ag/WO3 hybrid electrode is a promising choice for the fabrication of efficient and uniform large‐area OLEDs. [ABSTRACT FROM AUTHOR]

Objective: This cross-sectional study was conducted from April to July 2014 in Khartoum state, the Sudan, to investigate aerobic bacteria and fungi of skin lesions of fish in 3 different areas in Khartoum. Material and methods: A total of 50 samples were collected from the skin lesions of different types of fish including Synodontis species (n=17), Tilapia niloticus (n=15), Labeo niloticus (n=10), Hydrocynus species (n=4), and Clarias species (n=4). Liquid, semi-solid, and solid culture media like nutrient broth, blood agar, MacConkey agar, sabouraud dextrose agar (SDA), and Simmons citrate medium were used for the isolation and identification of bacteria and fungi. Besides, Gram staining and biochemical characterization were also conducted. Results: Culturing of the collected samples revealed growth of bacteria from all (100%), and growth of fungi could be found from 32% samples. A number of 188 bacteria were isolated, mainly Staphylococcus species, Bacillus species, Aeromonas species, Pseudomonas species, and Vibrio species. Besides, 16 fungi could be identified containing Aspergillus niger, A. flavus, A. fumigatus, and Phycomycete. Conclusion: Fishes with skin lesions are harboring many pathogenic bacteria and fungi and may act as a source of zoonotic infections and can transmit several pathogens to workers in fish industry and consumers. Therefore, thorough and strict routine inspection of fish is recommended to ensure safety and that there are no serious risks to consumers. [J Adv Vet Anim Res 2016; 3(4.000): 375-385]