Exploring temperature-dependent photoluminescence dynamics of colloidal CdSe nanoplatelets using machine learning approach.

The study explore machine learning (ML) techniques to predict temperature-dependent photoluminescence (PL) spectra in colloidal CdSe nanoplatelets (NPLs), leveraging polynomial regression models trained on experimental data from 85 to 270 K spanning temperatures to forecast PL spectra backward to 0 K and forward to 300 K. 6th-degree polynomial models with Tweedie regression were optimal for band energy ([Formula: see text]) predictions up to 300 K, while 9th-degree models with LassoLars and Linear Regression regressors were suitable for backward predictions to 0 K. For exciton energy ([Formula: see text]), the Lasso model of degree 5 and the Ridge model of degree 4 performed well up to 300 K, while the Tweedie model of degree 2 and Theil-Sen model of degree 2 showed promise for predictions to 0 K.

Photoluminescent chain-of-dimer anion in a novel hybrid halometallate (CHN){SbBr}: atypical behavior in one-dimensional anionic systems.

In pursuit of identifying less toxic hybrid compounds suitable for optoelectronic applications, we synthesized a novel homopiperazinium bromoantimonate(III), (CHN){SbBr}. It readily crystallized from an aqueous hydrobromic acid solution and was found to be stable both in air and upon heating up to 175 °C. The crystal structure of the new bromoantimonate(III) consisted of {SbBr} zigzag chains, which were composed of strongly trigonally distorted SbBr octahedral anions and CHN dications.

Collapses and revivals of spin polarization quantum oscillations in two-dimensional systems of spin 1/2 charged particles with spin-orbit interaction.

We analyzed spin polarization dynamics in a two-dimensional system of spin 1/2 charged particles with spin-orbit interaction in perpendicular magnetic field in the presence of external noise. It was shown that spin polarization reveals quantum oscillations, collapses, and revivals. The hierarchy of time scales corresponding to quantum oscillations, collapses, and revivals was identified and analyzed.

Extended investigation of the conductive characteristics of monoclinic tungstates with a BiWO ( = La, Pr or Nd) composition.

δ-BiO-based materials have long been a focus of interest as potential solid oxide fuel cell materials due to their high electrical conductivity. Here, extensive studies of thermal stability, polymorphism and conductivity have been carried out for the first time on BiWO ( = La, Pr or Nd) compounds in the ternary BiO-O-WO system, mentioned more than 20 years ago by Watanabe. The obtained single-phase materials were found to be sufficiently dense (more than 94%) and thermally stable (up to 900 °C).

Features of the defect structure of a lithium-gradient nonlinear optical single crystal LiNbO and their manifestation in the Raman spectra.

LiNbO crystal with a lithium composition gradient of Li/Nb = 0.8 wt%/cm (LiNbO) were obtained. A monotonic change in the edge of the UV absorption edge is observed when scanning the surface of the gradient crystal along the growth direction.

Temperature dependence of the electron and hole Landé -factors in CsPbI nanocrystals embedded in a glass matrix.

The coherent spin dynamics of electrons and holes in CsPbI perovskite nanocrystals in a glass matrix are studied by the time-resolved Faraday ellipticity technique in magnetic fields up to 430 mT across a temperature range from 6 K to 120 K. The Landé -factors and spin dephasing times are evaluated from the observed Larmor precession of electron and hole spins. The nanocrystal size in the three studied samples varies from about 8 to 16 nm, resulting in exciton transition varying from 1.

Modeling Temperature-Dependent Photoluminescence Dynamics of Colloidal CdS Quantum Dots Using Long Short-Term Memory (LSTM) Networks.

This study addresses the challenge of modeling temperature-dependent photoluminescence (PL) in CdS colloidal quantum dots (QD), where PL properties fluctuate with temperature, complicating traditional modeling approaches. The objective is to develop a predictive model capable of accurately capturing these variations using Long Short-Term Memory (LSTM) networks, which are well suited for managing temporal dependencies in time-series data. The methodology involved training the LSTM model on experimental time-series data of PL intensity and temperature.

Di(pyridin-2-yl)amino-substituted 1,10-phenanthrolines and their Ru(II)-Pd(II) dinuclear complexes: synthesis, characterization and application in Cu-free Sonogashira reaction.

Dinuclear complexes bearing Ru(II) photoactive centers are of interest for the development of efficient dual catalysts for many photocatalyzed reactions. Ditopic polypyridine ligands, bis(pyridin-2-yl)amino-1,10-phenanthrolines, containing an additional coordination site (bis(pyridin-2-yl)amine, dpa) at positions 3, 4 or 5 of the 1,10-phenanthroline core (Phen-3NPy2, Phen-4NPy2 and Phen-5NPy2) were synthesized. They were used as bridging ligands to obtain dinuclear complexes [(bpy)Ru(Phen-NPy2)PdCl](PF) (Ru(Phen-NPy2)Pd) in good yields stepwise complexation.

Impact of Graphene Oxide Nanoparticles on In Vitro Development of a Mouse Preimplantation Embryo and Interaction With the Zona Pellucida.

The development of assisted reproductive technologies increases the likelihood of nanoparticles' (NPs) direct contact with gametes and embryos in in vitro conditions. Analyzing the influence of nanomaterials on the early mammalian embryo becomes increasingly relevant. This work is devoted to the effect of graphene oxide (GO) NPs on the in vitro development of mammalian embryos.

Synchronization transitions in a system of superdiffusively coupled neurons: Interplay of chimeras, solitary states, and phase waves.

In this paper, a network of interacting neurons based on a two-component system of reaction-superdiffusion equations with fractional Laplace operator responsible for the coupling configuration and nonlinear functions of the Hindmarsh-Rose model is considered. The process of synchronization transition in the space of the fractional Laplace operator exponents is studied. This parametric space contains information about both the local interaction strength and the asymptotics of the long-range couplings for both components of the system under consideration.

Multitemperature atomic ensemble: Nonequilibrium evolution after ultrafast electronic excitation.

Ultrafast laser radiation or beams of fast charged particles primarily excite the electronic system of a solid driving the target transiently out of thermal equilibrium. Apart from the nonequilibrium between the electrons and atoms, each subsystem may be far from equilibrium. From first principles, we derive the definition of various atomic temperatures applicable to electronically excited ensembles.

Salt-coated air oxidation nanodiamond surface purification with a photoluminescence spectroscopy quality control.

Emerging fields of quantum technologies and biomedical applications demand pure nanodiamonds (NDs) with well-defined surface chemistry. Therefore, an inexpensive, scalable and eco-friendly ND surface purification technology is required. In this study, we report our method, salt-coated air oxidation (SCAO) thermal annealing, to achieve uniform purification of a ND surface without the loss of diamond material.

Microdosimetric Simulation of Gold-Nanoparticle-Enhanced Radiotherapy.

Conventional X-ray therapy (XRT) is commonly applied to suppress cancerous tumors; however, it often inflicts collateral damage to nearby healthy tissue. In order to provide a better conformity of the dose distribution in the irradiated tumor, proton therapy (PT) is increasingly being used to treat solid tumors. Furthermore, radiosensitization with gold nanoparticles (GNPs) has been extensively studied to increase the therapeutic ratio.

Formation of directed wide-aperture flows of runaway electrons in air-filled magnetized diodes.

This paper presents the results of research, development, and testing of magnetically insulated air diodes with replaceable graphite and stainless-steel tubular and coaxial cathodes of various configurations capable of generating directed bunches of runaway electrons. At the anode, the bunches have cross sections shaped as circles or rings with an outer diameter of 1-2 cm. The durations of the bunches, which carry currents of a few to tens of amperes, range from tens of picoseconds to 100 ps, and their charges range from tenths of a nanocoulomb to a few nanocoulombs.

Laser-synthesized plasmonic HfN-based nanoparticles as a novel multifunctional agent for photothermal therapy.

Hafnium nitride nanoparticles (HfN NPs) can offer appealing plasmonic properties at the nanoscale, but the fabrication of stable water-dispersible solutions of non-toxic HfN NPs exhibiting plasmonic features in the window of relative biological transparency presents a great challenge. Here, we demonstrate a solution to this problem by employing ultrashort (femtosecond) laser ablation from a HfN target in organic solutions, followed by a coating of the formed NPs with polyethylene glycol (PEG) and subsequent dispersion in water. We show that the fabricated NPs exhibit plasmonic absorption bands with maxima around 590 nm, 620 nm, and 650 nm, depending on the synthesis environment (ethanol, acetone, and acetonitrile, respectively), which are largely red-shifted compared to what is expected from pure HfN NPs.

Structure and luminescence properties of EuF and SrF:Eu nanoparticles after microwave plasma annealing in "methane-hydrogen".

Recently, progress has been made in fabricating diamond-based scintillators with integrated rare-earth luminescent particles. These luminescent particles are integrated into the bulk of diamond during their synthesis by chemical vapor deposition (CVD). However, the growth conditions include a chemically aggressive plasma environment and elevated temperatures, which results in the partial degradation of particles and a decrease in the intensity of their luminescence.

Boron Nanoparticle-Enhanced Proton Therapy: Molecular Mechanisms of Tumor Cell Sensitization.

Boron-enhanced proton therapy has recently appeared as a promising approach to increase the efficiency of proton therapy on tumor cells, and this modality can further be improved by the use of boron nanoparticles (B NPs) as local sensitizers to achieve enhanced and targeted therapeutic outcomes. However, the mechanisms of tumor cell elimination under boron-enhanced proton therapy still require clarification. Here, we explore possible molecular mechanisms responsible for the enhancement of therapeutic outcomes under boron NP-enhanced proton therapy.

4,7-Substituted 1,10-phenanthroline-2,9-dicarboxamides: photophysics of ligands and their complexes with the Eu-Gd-Tb triad.

The impact of substituents at the 4- and 7-positions of 1,10-phenanthroline-2,9-dicarboxamides on the photophysical properties of the ligands and their coordination compounds with the lanthanide triad-europium, gadolinium, and terbium-was analyzed. This study demonstrates how modification of the electronic nature of ligands through the incorporation of diverse functional groups affects the luminescence properties of their complexes. The introduction of various substituents leads to the appearance of intra-ligand or ligand-to-ligand charge transfer (CT) states.

Optical Characteristics of a New Molecular Complex: "Nafion-Colloidal CdSe/CdS/ZnS Nanocrystals".

Here, the optical properties of the Nafion polymer membrane containing colloidal CdSe/CdS/ZnS nanocrystals embedded by diffusion have been studied. The CdSe/CdS/ZnS nanocrystals have a core/shell/shell appearance. All experiments were carried out at room temperature (22 ± 2) °C.

Polysaccharide from Helianthus tuberosus L. as a potential radioprotector.

Introduction: Radioprotectors help to protect the body or at least minimize the negative consequences of radiation exposure. The present study aimed to assess the radioprotective potential of Helianthus tuberosus L. polysaccharide (HTLP) in vitality and micronuclei tests.

Strong diffraction effects accompany the transmission of a laser beam through inhomogeneous plasma microstructures.

In the study we thoroughly analyze diffraction effects accompanying the laser beam transmission through inhomogeneous plasma microstructures and simulate their diffraction patterns at the object output and in the near field. For this we solve the scalar Helmholtz wave equation in the first Rytov approximation and compute the diffraction spreading of the transmitted beam in free space. Diffraction effects are found to arise within the beam passage through inhomogeneous plasma microstructures even in the simplest approximations of the laser beam interaction with plasma.

Fluorescence saturation imaging microscopy: molecular fingerprinting with a standard confocal microscope.

Molecular specificity in fluorescence imaging of cells and tissues can be increased by measuring parameters other than intensity. For instance, fluorescence lifetime imaging became a widespread modality for biomedical optics. Previously, we suggested using the fluorescence saturation effect at pulsed laser excitation to map the absorption cross-section as an additional molecular contrast in two-photon microscopy [Opt.