Nanoantennas made of high-index dielectrics with low losses in visible and infrared frequency ranges have emerged as a novel platform for advanced nanophotonic devices. On the other hand, halide ...perovskites are known to possess high refractive index, and they support excitons at room temperature with high binding energies and quantum yield of luminescence that makes them very attractive for all-dielectric resonant nanophotonics. Here we employ halide perovskites to create light-emitting nanoantennas with enhanced photoluminescence due to the coupling of their excitons to dipolar and multipolar Mie resonances. We demonstrate that the halide perovskite nanoantennas can emit light in the range of 530–770 nm depending on their composition. We employ a simple technique based on laser ablation of thin films prepared by wet-chemistry methods as a novel cost-effective approach for the fabrication of resonant perovskite nanostructures.
Achieving efficient localization of white light at the nanoscale is a major challenge due to the diffraction limit, and nanoscale emitters generating light with a broadband spectrum require ...complicated engineering. Here we suggest a simple, yet highly efficient, nanoscale white-light source based on a hybrid Si/Au nanoparticle with ultrabroadband (1.3–3.4 eV) spectral characteristics. We incorporate this novel source into a scanning-probe microscope and observe broadband spectrum of photoluminescence that allows fast mapping of local optical response of advanced nanophotonic structures with submicron resolution, thus realizing ultrabroadband near-field nanospectroscopy.
Excitons in lead bromide perovskites exhibit high binding energy and high oscillator strength, allowing for a strong light‐matter coupling regime in the perovskite‐based cavities localizing photons ...at the nanoscale. This opens up the way for the realization of exciton‐polariton Bose–Einstein condensation and polariton lasing at room temperature – the inversion‐free low‐threshold stimulated emission. However, polariton lasing in perovskite planar photon cavities without Bragg mirrors has not yet been observed and proved experimentally. In this study, perovskite metasurface is employed, fabricated with nanoimprint lithography, supporting so‐called exceptional points to demonstrate the room‐temperature polariton lasing. The exceptional points in exciton‐polariton dispersion of the metasurface appear upon optically pumping in the nonlinear regime in the spectral vicinity of a symmetry‐protected bound state in the continuum providing high mode confinement with the enhanced local density of states beneficial for polariton condensation. The observed lasing emission possesses high directivity with a divergence angle of 1° over one axis. The employed nanoimprinting approach for solution‐processable large‐scale polariton lasers is compatible with various planar photonic platforms suitable for on‐chip integration.
A strong light‐matter coupling regime is observed at room temperature in the lead‐halide perovskite metasurface fabricated by nanoimprint lithography. Thanks to the high polariton nonlinearity under the non‐resonant pump, exceptional points appear providing enhanced local density of states and exciton‐polariton condensation with low‐threshold highly‐directive lasing.
A complete package ensemble, complex of physical and chemical investigations was conducted: x-ray phase analysis, differential thermal analysis, chemical analysis of waste generated in the production ...of vanadium. It was established that these wastes, which contain 17.39% Mn
2
O
3
in their composition, are a promising raw material for the production of wall ceramics with volumetric-staiing. The effect of heat treatment at 200, 500, 600, and 700°C on the phase composition of the wastes from the production of vanadium was investigated.
•Synthesis of Al-, Zn- and Ti-containing metal–organic frameworks is presented.•These materials effectively adsorb free fatty acids and peroxides in vegetable oils.•These materials are more effective ...adsorbents as compared with traditional adsorbents.•Used adsorbent can be easily regenerated and recycled at least five times.•The adsorption mechanism of free fatty acids and peroxides is proposed.
Reported here is the synthesis of aluminum-, zinc- and titanium-containing metal–organic frameworks based on terephthalic acid and an investigation on the possibility of using these compounds as adsorbents for the purification of unrefined vegetable oils. It is found that aluminum-, zinc- and titanium-containing metal–organic frameworks improve the physicochemical properties of unrefined vegetable oils (more pleasant taste and odor) due to the binding of free fatty acids and peroxide compounds. It is established that the synthesized materials are more effective in these respects as compared with traditional adsorbents. An adsorption mechanism of free fatty acids and peroxides is proposed. Last but not least, the used MOF can be easily recycled at least five times, via solvent washing.
A resource- and energy-saving technology for using foam paints to decorate manufactured glass articles was developed. The optimal parameters for firing the coating by a plasma-forming argon-gas flow ...were determined. The effect of sodium liquid glass on the quality of a decorative coating was investigated.
Background
Cognitive impairment is an irreversible, aging-associated condition that robs people of their independence. The purpose of this study was to investigate possible causes of this condition ...and propose preventive options.
Methods
We assessed cognitive status in long-living adults aged 90+ (
n
= 2,559) and performed a genome wide association study using two sets of variables: Mini-Mental State Examination scores as a continuous variable (linear regression) and cognitive status as a binary variable (> 24, no cognitive impairment; <10, impairment) (logistic regression).
Results
Both variations yielded the same polymorphisms, including a well-known marker of dementia, rs429358in the APOE gene. Molecular dynamics simulations showed that this polymorphism leads to changes in the structure of alpha helices and the mobility of the lipid-binding domain in the APOE protein.
Conclusion
These changes, along with higher LDL and total cholesterol levels, could be the mechanism underlying the development of cognitive impairment in older adults. However, this polymorphism is not the only determining factor in cognitive impairment. The polygenic risk score model included 45 polymorphisms (ROC AUC 69%), further confirming the multifactorial nature of this condition. Our findings, particularly the results of PRS modeling, could contribute to the development of early detection strategies for predisposition to cognitive impairment in older adults.
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