A series of blue and green-emitting phosphorescent heteroleptic cyclometalated Ir(III) complexes with mesityl-phenyl-imidazole Ligand for organic light-emitting devices are investigated theoretically ...to explore their electronic structures, spectroscopic properties and the application value for organic light emitting devices. The geometries, electronic structures, lowest-lying singlet absorptions, and triplet emissions of Ir(mpim)3, and the theoretically designed models Ir(F-mpim)3, Ir(F2-mpim)3, (mpim)2Ir(acac), (F-mpim)2Ir(acac), (F2-mpim)2Ir(acac), (mpim)2Ir(tpip), (F-mpim)2Ir(tpip), (F2-mpim)2Ir(tpip), are investigated with Density Functional Theory (DFT) approaches, where mpim denotes 1-mesityl-2-phenyl-1H-imidazole, F-mpim denotes 2-(4-fluorophenyl)-1-mesityl-1H-imidazole, F2-mpim denotes 2-(2,4-difluorophenyl)-1-mesityl-1H-imidazole, acac denotes acetylacetonate, and tpip denotes tetraphenylimido-diphosphinate.
A series of heteroleptic cyclometalated Ir (III) complexes, which are used for OLED application,were investigated by DFT and TD-DFT method. The frontier molecular orbital character and charge transfer charactershown that they have theadvantagesof low efficiency roll-offproperties, which is a “stumbling block”in the process of OLED solid-lighting’s development. Namely, means the materials will play animportant role in the journey development of OLED. Display omitted
•Cyclometalated iridium (III) complexes have received special attention as dopants for harvesting the otherwise nonemissive triplet states formed in OLEDs, but now, most of them cannot satisfy to be used for the applications, especially for blue and green, since that a fast reduction in efficiency known as roll-off, however, occurs when the drive current increases, this leads to a much lower luminance and more power consumption.•Thus in this paper, in order to find a series of blue and green OLED materials with low efficiency roll-off properties, we theoretical design and investigate a series of Iridium complexes.•The geometries, electronic structures, the lowest-lying singlet absorptions, triplet emissions properties and the application value for organic light emitting devices were all analysed by theory in this article.
Polyelectrolyte-surfactant complexes(PESCs) were fabricated through the interaction of poly(acrylic acid) and four different cationic surfactants or their mixtures. PESC membranes were prepared by ...solution casting method and were applied in ethanol recovery from aqueous solution via pervaporation. Elemental analysis(EA), Fourier transform infrared spectroscopy(FTIR), water contact angle(CA) measurement, differential scanning calorimetry(DSC) and X-ray scattering were employed to characterize the composition, structure and properties of PESCs. The results reveal that the investigated PESCs are similar in hydrophobicity but different in hierarchical nanostructures. In separating 5 wt% ethanol/water mixture, PESC membranes with high crystallinity will have both low flux and ethanol selectivity because of the high packing density and low permeability of crystalline regions. Meanwhile, the hierarchical nanostructures of PESC membranes change under pervaporation environment as was revealed by in situ synchrotron radiation X-ray scattering measurement. That is, the crystalline region could melt at high temperature in swelling state, thus consequently enhancing the ethanol selectivity.
Trans-tympanic injection into the middle ear has long been the standard for local delivery of compounds in experimental studies. Here we demonstrate the advantages of the novel method of ...intra-tympanic injection through the otic bone for the delivery of compounds or siRNA into the adult mouse cochlea. First, a fluorescently-conjugated scrambled siRNA probe was applied via intra-tympanic injection into the middle ear cavity and was detected in sensory hair cells and nerve fibers as early as 6 h after the injection. The fluorescent probe was also detected in other cells of the organ of Corti, the lateral wall, and in spiral ganglion cells 48 h after the injection. Furthermore, intra-tympanic delivery of Nox3 siRNA successfully reduced immunofluorescence associated with Nox3 in outer hair cells 72 h after injection by 20%. Drug or siRNA delivery via intra-tympanic injection does not compromise the tympanic membrane or interfere with noise-induced hearing loss, while trans-tympanic injections significantly altered the cochlear response to noise exposure. In summary, intra-tympanic injection through the otic bone into the middle ear cavity provides a promising approach for delivery of compounds or siRNA to cochlear hair cells of adult mice, relevant for the study of mechanisms underlying inner ear insults and, specifically, noise-induced hearing loss.
► Fluorescence-conjugated siRNA probes are taken up by cochlear sensory hair cells. ► siRNA target protein is successfully suppressed in cochlear sensory hair cells. ► Intra-tympanic delivery of siRNA or other compounds is suitable for study of NIHL.
The development of probes for rapid and selective detection of peroxynitrite in vivo is of great importance in biological science. We investigate different photoinduced electron transfer (PIET) ...processes of two generations of peroxynitrite probes. Each has fluorescein and phenol moieties; one is conjugated by an ether linkage while the other is conjugated via an amine linkage. Using theoretical calculations, we demonstrated that the PIET in the probe with an ether linkage occurs from the benzoic acid to the xanthene moiety. In contrast, the PIET in the probe with an amine linkage occurs from the phenol moiety to the fluorescein. This suggests that better sensitivity can be accomplished in probes with an amine linkage than with an ether linkage. Following this model, we designed two novel peroxynitrite probes and simulated their detection capabilities in the near-infrared region.
The anti-cracking properties of polymer-modified asphalt depend largely on the molecular structure of the polymer modifier. However, the mysterious structure-performance relationship is still ...elusive. In this paper, three kinds of polymers with different chain structures were selected to address this issue. The indices of styrene, trans-butadiene, aliphatic branched-chain, and aliphatic long-chain from the infrared spectrum were used to quantify the functional group compositions of polymer modifiers. Viscoelastic parameters, including relaxation time, dissipation energy ratios, and stiffness were assessed to illustrate the anti-cracking properties of polymer-modified asphalt. Results showed that relaxation time and dissipation energy ratios were mainly determined by the polymer network strength, molecular size, aliphatic chain feature, and the orientations speed of aliphatic chains. The short relaxation time and high dissipation ratio lead to the low stiffness and favorable low-temperature performance of asphalt. The improvement of these performances requires a polymer with high indices of an aliphatic long-chain, styrene, aliphatic branched-chain, and trans-butadiene, respectively. An aliphatic-long chain, aliphatic branched-chain, and trans-butadiene were soft segments in asphalt while styrene was the rigid segment. The soft segments affect the intramolecular friction, orientation, and thermal motion at low temperatures, whereas the rigid segment enhances the strength of polymer networks. Thus, the anti-cracking property of polymer-modified asphalt can be improved by adjusting the ratio of soft and rigid segments in the polymer modifier.
Laser-induced damage often determines the effective lifetime of an optic in large high-energy laser facilities. We present the damage performance on the rear surface of a large-aperture KDP crystal ...for 351 nm, 5 ns laser pulses. Surface damage shows a lower threshold than bulk damage after conditioning. Craters initiated on the scratch are found to increase with the shot number before filling the scratch. The experimental results reveal that damage initiation is mainly caused by extrinsic nanoabsorbers buried in the surface during the large-aperture laser operation.
Polyelectrolyte complexes (PECs) commonly suffer from poor processability owing to their ionic crosslinking nature, a problem which spurs increasing interest in processable PECs. New processing ...technologies have been exploited to render PECs processable, but usually at the expense of compromising their mechanical properties. Through a conceptually novel strategy of "complexation-sulfation", here we engineer solution-processable PECs derived from a strong polyacid, in pursuit of high mechanical strength combined with exceptional separation performance. Effects of chemical structures and compositions on mechanical properties of these PEC membranes were studied. It was found that the mechanical properties of these PEC membranes based on strong "ion-pairs" were substantially enhanced, with their tensile strength and elongation at break reaching as high as 108.3 MPa and 5.0%, respectively. In addition, PEC membranes exhibited a high performance in separating water-ethanol mixtures. For example, the flux and water content in the permeate for PEC membranes were 2100 g m super(-2) h super(-1) and 99.58 wt%, respectively, in dehydrated 10 wt% water-ethanol mixture at 70 degree C.
Objective
This cross‐sectional study aimed to determine the epidemiology of olfactory and gustatory dysfunctions related to COVID‐19 in China.
Methods
This study was conducted by 45 tertiary Grade‐A ...hospitals in China. Online and offline questionnaire data were obtained from patients infected with COVID‐19 between December 28, 2022, and February 21, 2023. The collected information included basic demographics, medical history, smoking and drinking history, vaccination history, changes in olfactory and gustatory functions before and after infection, and other postinfection symptoms, as well as the duration and improvement status of olfactory and gustatory disorders.
Results
Complete questionnaires were obtained from 35,566 subjects. The overall incidence of olfactory and taste dysfunction was 67.75%. Being female or being a cigarette smoker increased the likelihood of developing olfactory and taste dysfunction. Having received four doses of the vaccine or having good oral health or being a alcohol drinker decreased the risk of such dysfunction. Before infection, the average olfactory and taste VAS scores were 8.41 and 8.51, respectively; after infection, they decreased to 3.69 and 4.29 and recovered to 5.83 and 6.55 by the time of the survey. The median duration of dysosmia and dysgeusia was 15 and 12 days, respectively, with 0.5% of patients having symptoms lasting for more than 28 days. The overall self‐reported improvement rate was 59.16%. Recovery was higher in males, never smokers, those who received two or three vaccine doses, and those that had never experienced dental health issues, or chronic accompanying symptoms.
Conclusions
The incidence of dysosmia and dysgeusia following infection with the SARS‐CoV‐2 virus is high in China. Incidence and prognosis are influenced by several factors, including sex, SARS‐CoV‐2 vaccination, history of head‐facial trauma, nasal and oral health status, smoking and drinking history, and the persistence of accompanying symptoms.
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