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The composition and distribution of storage substances in rice endosperm directly affect grain quality. A floury endosperm mutant, wcr (white-core rice), was identified, exhibiting a loose arrangement of starch granules with a floury opaque appearance in the inner layer of mature grains, resulting in reduced grain weight. The total starch and amylose content remained unchanged, but the levels of the four component proteins in the mutant brown rice significantly decreased. Additionally, the milled rice (inner endosperm) showed a significant decrease in total starch and amylose content, accompanied by a nearly threefold increase in albumin content. The swelling capacity of mutant starch was reduced, and its chain length distribution was altered. The target gene was mapped on chromosome 5 within a 65 kb region. A frameshift mutation occurred due to an insertion of an extra C base in the second exon of the cyOsPPDKB gene, which encodes pyruvate phosphate dikinase. Expression analysis revealed that wcr not only affected genes involved in starch metabolism but also downregulated expression levels of genes associated with storage protein synthesis. Overall, wcr plays a crucial role as a regulator factor influencing protein synthesis and starch metabolism in rice grains. [ABSTRACT FROM AUTHOR]

Controlled synthesis of lead‐halide perovskite crystals is challenging yet attractive because of the pivotal role played by the crystal structure and growth conditions in regulating their properties. This study introduces data‐driven strategies for the controlled synthesis of oriented quasi‐spherical CsPbBr3, alongside an investigation into the synthesis mechanism. High‐throughput rapid characterization of absorption spectra and color under ultraviolet illumination was conducted using 23 possible ligands for the synthesis of CsPbBr3 crystals. The links between the absorption spectra slope (difference in the absorbance at 400 nm and 450 nm divided by a wavelength interval of 50 nm) and crystal size were determined through statistical analysis of more than 100 related publications. Big data analysis and machine learning were employed to investigate a total of 688 absorption spectra and 652 color values, revealing correlations between synthesis parameters and properties. Ex situ characterization confirmed successful synthesis of oriented quasi‐spherical CsPbBr3 perovskites using polyvinylpyrrolidone and Acacia. Density functional theory calculations highlighted strong adsorption of Acacia on the (110) facet of CsPbBr3. Optical properties of the oriented quasi‐spherical perovskites prepared with these data‐driven strategies were significantly improved. This study demonstrates that data‐driven controlled synthesis facilitates morphology‐controlled perovskites with excellent optical properties. [ABSTRACT FROM AUTHOR]

Element tuning of targeted materials and obtaining the optimal synthesis recipe are major goals for many material scientists. However, this is often limited by conventional trial‐and‐error procedures, which are time‐consuming and labor‐intensive. In this work, fine element tuning of halide double perovskite Cs2NaxAg1‐xInyBi1‐yCl6 is conducted by performing a data‐driven investigation combining high‐throughput experiments with machine learning (ML). A positive correlation between the more accessible R value in emission RGB values (the intensities of the red/green/blue primary colors) and photoluminescence intensity is revealed, and over a thousand R values of the Cs2NaxAg1‐xInyBi1‐yCl6 crystals synthesized with different additives and element compositions are collected. More importantly, the volume ratios of Na+/Ag+ (VNa: VAg) and Bi3+/In3+ (VBi: VIn) with the corresponding R values are correlated through ML, and the synergistic regulation of the two ion pairs is revealed. A possible correlation between R and XRD is also proposed. Finally, different emission intensities of LED beads coated with Cs2NaxAg1‐xInyBi1‐yCl6 synthesized using parameters obtained from ML are demonstrated, and an emission enhancement of ≈50 times is observed between the brightest and dimmest LEDs. This work illustrates that data‐driven investigation helps guide material synthesis and will significantly reduce the workload for developing novel materials, especially for complex compositions. [ABSTRACT FROM AUTHOR]

Controlled synthesis of lead-halide perovskite crystals is challenging yet attractive because of the pivotal role played by the crystal structure and growth conditions in regulating their properties. This study introduces data-driven strategies for the controlled synthesis of oriented quasi-spherical CsPbBr 3 , alongside an investigation into the synthesis mechanism. High-throughput rapid characterization of absorption spectra and color under ultraviolet illumination was conducted using 23 possible ligands for the synthesis of CsPbBr 3 crystals. The links between the absorption spectra slope (difference in the absorbance at 400 nm and 450 nm divided by a wavelength interval of 50 nm) and crystal size were determined through statistical analysis of more than 100 related publications. Big data analysis and machine learning were employed to investigate a total of 688 absorption spectra and 652 color values, revealing correlations between synthesis parameters and properties. Ex situ characterization confirmed successful synthesis of oriented quasi-spherical CsPbBr 3 perovskites using polyvinylpyrrolidone and Acacia. Density functional theory calculations highlighted strong adsorption of Acacia on the (110) facet of CsPbBr 3 . Optical properties of the oriented quasi-spherical perovskites prepared with these data-driven strategies were significantly improved. This study demonstrates that data-driven controlled synthesis facilitates morphology-controlled perovskites with excellent optical properties., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The ground and excited state photophysical properties of a series of fac-[Re(L)(CO) 3 (α-diimine)] n+ complexes, where L = Br - , Cl - , 4-dimethylaminopyridine (dmap) and pyridine (py) have been extensively studied utilizing numerous electronic and vibrational spectroscopic techniques in conjunction with a suite of quantum chemical methods. The α-diimine ligand consists of 1,10-phenanthroline with the highly electron donating triphenylamine (TPA) appended in the 5 position. This gives rise to intraligand charge transfer (ILCT) states lying lower in energy than the conventional metal-to-ligand charge transfer (MLCT) state, the energies of which are red and blue-shifted, respectively, as the ancillary ligand, L becomes more electron withdrawing. The emitting state is 3 ILCT in nature for all complexes studied, characterized through transient absorption and emission, transient resonance Raman (TR 2 ), time-resolved infrared (TRIR) spectroscopy and TDDFT calculations. Systematic modulation of the ancillary ligand causes unanticipated variation in the 3 ILCT lifetime by 2 orders of magnitude, ranging from 6.0 μs for L = Br - to 27 ns for L = py, without altering the nature of the excited state formed or the relative order of the other CT states present. Temperature dependent lifetime measurements and quantum chemical calculations provide no clear indication of close lying deactivating states, MO switching, contributions from a halide-to-ligand charge transfer (XLCT) state or dramatic changes in spin-orbit coupling. It appears that the influence of the ancillary ligand on the excited state lifetime could be explained in terms of energy gap law, in which there is a correlation between ln( k nr ) and E em with a slope of -21.4 eV -1 for the 3 ILCT emission.