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Ultra‐long room temperature phosphorescence (ULRTP) materials show valuable applications in encryption, biological imaging, and many other fields. Amazingly, the concomitant impurities from raw materials that are normally ignored contribute dramatically to the ULRTP. In this study, CzPMB [9‐(4‐bromo‐3‐methylphenyl)‐9H‐carbazole] with phosphorescent quantum efficiency of 64% is prepared from commercial carbazole, but the phosphorescent efficiency is drastically reduced to < 2% once trace impurity (5‐(4‐bromo‐3‐methylphenyl)‐5H‐benzo[b]carbazole) is separated. HPLC studies demonstrated the separated impurity is a byproduct derived from trace benzocarbazole in commercial carbazole. Subsequently, the ULRTP for the CzPMB synthesized from lab‐made carbazole is totally unobserved, strongly confirming the dramatic impact of impurity. A defect trapping mechanism in multicomponent system rather than heavy atom effect is proposed for highly efficient ULRTP after carefully analyzing the crystal packings and molecular energy levels. Inspired by this discovery, a series of effective ULRTP bi‐component systems with the highest phosphorescence efficiency of 64.1% are reproduced by directed host‐guest doping. This strategy paves a viable path for the design of organic materials with highly efficient ULRTP. [ABSTRACT FROM AUTHOR]

A series of platinum(II) complexes bearing 1,3-bis(2-pyridylimino)isoindoline (BPI) derivatives as ligand have been prepared by substitution of the coordinated Cl in precursors [Pt(L)Cl] [L = L1 ( 1), L2 ( 2), L3 ( 3)] by a monodentate strong-field ligand such as CN-, CN-cyclohexyl, PPh3, NCS-, PhS-, or N(CN)2-. Most of these compounds display orange-to-red luminescence in both the solid state and solution at ambient temperature. Compared with precursors 1- 3, both low-energy absorption and emission bands in ligand-substituted platinum(II) complexes 4- 13 exhibit distinct blueshifts. The emission of platinum(II) complexes with CN-containing monodentate ligands shows progressive blueshifts with increasing ligand field strength: 609 ( 10, NCS-) → 603 [ 12, N(CN)2-] → 590 ( 4, CN-) → 581 nm ( 7, C≡N-cyclohexyl). The emission of complexes 4- 9 originates mainly from the 3[π → π*(BPI)] 3IL triplet excited state, mixed with some 3[dπ(Pt) → π*(BPI)] 3MLCT character. In contrast, the emission of 10- 13 arises from a clearly increased 3[π(L) → π*(BPI)] 3LLCT state with reduced 3[π → π*(BPI)] 3IL and 3[5d(Pt) → π*(BPI)] 3MLCT character. Noticeably, dicyanamido-linked dinuclear complex 13 displays a significant ligand-ligand electronic interaction between the two BPI across the Pt-N≡C-N-C≡N-Pt bridge with remarkable LLCT character from one BPI to the other. [ABSTRACT FROM AUTHOR]

A major objective of quantitative trait locus (QTL) studies is to find genes/markers that can be used in breeding programs via marker assisted selection (MAS). We surveyed the QTLs for yield and yieldrelated traits and their genomic distributions in common wheat (Triticum aestivum L.) in the available published reports. We then carried out a meta-QTL (MQTL) analysis to identify the major and consistent QTLs for these traits. In total, 55 MQTLs were identified, of which 12 significant MQTLs were located on wheat chromosomes 1A, 1B, 2A, 2D, 3B, 4A, 4B, 4D and 5A. Our study showed that the genetic control of yield and its components in common wheat involved the important genes such as Rht and Vrn. Furthermore, several significant MQTLs were found in the chromosomal regions corresponding to several rice genomic locations containing important QTLs for yield related traits. Our results demonstrate that meta-QTL analysis is a powerful tool for confirming the major and stable QTLs and refining their chromosomal positions in common wheat, which may be useful for improving the MAS efficiency of yield related traits. [ABSTRACT FROM AUTHOR]