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The formation of cesium lead bromide (CsPbBr3 ) nanocrystal superlattices (NC SLs) is accompanied by a red shift in the NC photoluminescence (PL). The values of the PL red shift reported in the literature range from none to 100 meV without unifying explanation of the differences. Using a combination of confocal PL microcopy and steady-state

Fully inorganic cesium lead halide perovskite (CsPbX3) nanocrystals (NCs) have been extensively studied due to their excellent optical properties, especially their high photoluminescence quantum yield (PLQY) and the ease with which the PL can be tuned across the visible spectrum. So far, most strategies for synthesizing CsPbX3 NCs are highl

We report the synthesis of various binary and ternary inorganic and hybrid organic-inorganic iodide nanocrystals (NCs) starting from molecular iodine (I2). The synthesis described herein utilizes a reaction between I2 and oleylamine, which results in oleylammonium iodide, an iodide precursor that can be directly used in the preparation of iodide-based NCs. The generality of the synthesis was demon

We show here the first colloidal synthesis of double perovskite Cs2AgInCl6 nanocrystals (NCs) with a control over their size distribution. In our approach, metal carboxylate precursors and ligands (oleylamine and oleic acid) are dissolved in diphenyl ether and reacted at 105 °C with benzoyl chloride. The resulting Cs2AgInCl6 NCs exhibit the expected double perovskite crystal structure, are stable

In laser spectroscopy, high photon flux can perturb the sample away from thermal equilibrium, altering its spectroscopic properties. Here, we describe an optical beam scanning apparatus that minimizes repetitive sample excitation while providing shot-to-shot sample exchange for samples such as cryostats, films, and air-tight cuvettes. In this apparatus, the beam crossing point is moved within the

Femtosecond two-dimensional Fourier transform spectroscopy is used to determine the static bandgap inhomogeneity of a colloidal quantum dot ensemble. The excited states of quantum dots absorb light, so their absorptive two-dimensional (2D) spectra will typically have positive and negative peaks. It is shown that the absorption bandgap inhomogeneity is robustly determined by the slope of the nodal

In experiments with high photon flux, it is necessary to rapidly remove the sample from the beam and to delay re-excitation until the sample has returned to equilibrium. Rapid and complete sample exchange has been a challenge for air-sensitive samples and for vibration-sensitive experiments. Here, a compact spinning sample cell for air and moisture sensitive liquid and thin film samples is describ

Pump-probe polarization anisotropy measurements with 15 fs pulses are employed to investigate the electronic structure of PbS quantum dots. The initial anisotropy at the bandgap is anomalously low (<0.1) and suggests large electronic couplings.

The first low-energy Coulomb-excitation measurement of the radioactive, semi-magic, two proton-hole nucleus 206Hg, was performed at CERN's recently-commissioned HIE-ISOLDE facility. Two γ rays depopulating low-lying states in 206Hg were observed. From the data, a reduced transition strength B(E2; 2+1 → 0+1) = 4.4(6) W.u. was determined, the first such value for an N=126 nucleus south of 208Pb, wh

A recent case of a flawed medical AI system that was backed by public funding provides an opportunity to discuss the impact of government policies and regulation in AI.

Multi-gigawatt-scale hydrogen production by water electrolysis is central in the green transition when it comes to storage of energy and forming the basis for sustainable fuels and materials. Alkaline water electrolysis plays a key role in this context, as the scale of implementation is not limited by the availability of scarce and expensive raw materials. Even though it is a mature technology, th

This article addresses the development under Xi Jinping of ideological and political education at the university level. It provides an overview of trends among youth, major policies and recent developments, and an analysis of how ideological and political education is organised at universities and incorporated into the curricula. It also argues that ideological and political education targeting yo

The increasing investment in and emphasis on ideological andpolitical education at Chinese universities, and statements, including by Xi Jinping himself, and other policies related to youth and higher education, reveals a growing concern about youth. This article provides a brief overview of developments and policies affecting Chinese youth, including the emergence of new values among them.

OBJECTIVE: The aim of this study was to investigate if desquamated oral epithelial cells (DOECs) express the epidermal growth factor (EGF) and if these cells thereby may contribute to salivary EGF contents.BACKGROUND: DOECs have recently been shown to harbor the antimicrobial peptide LL-37, proposing that they may also store other biologically important salivary peptides/proteins. The EGF peptide

Small-angle neutron scattering (SANS) experiments were conducted on cyclic and linear polymers of racemic and l-lactides (PLA) with the goal of comparing chain configurations, scaling, and effective polymer–solvent interactions of the two topologies in acetone-d6 and THF-d8. There are limited reports of SANS results on cyclic polymers due to the lack of substantial development in the field unt

This work demonstrates the first continuous, stable, and safe operation of organometallic reactions in flow under ambient conditions with high moisture tolerance and clogging resistance. The addition of deep eutectic solvents (DESs), such as glyceline (choline chloride/glycerol) and reline (choline chloride/urea), overcomes the previous limitations associated with the need for cryogenic conditions

Mixtures of sulfobetaine based lipids with phosphocholine phospholipids are of interest in order to study the interactions between zwitterionic surfactants and the phospholipids present in cell membranes. In this study we have investigated the structure of mixed monolayers of sulfobetaines and phosphocholine phospholipids. The sulfobetaine used has a single 18-carbon tail, and is referred to as SB