Phosphonium cations bearing different alkyl chains were coupled with several common anions so as to prepare ionic liquids (ILs) with diverse hydrophobicity. A temperature-driven phase behaviour of the mixture of various ILs and water has been examined. A few ILs were found to exhibit temperature-sensitive lower critical solution temperature (LCST)-type phase transition after mixing with water. The phase separation temperature (T c ) of the IL/water mixtures depended strongly on the hydrophobicity of the component ions as well as mixing ratio. The number of water molecules per ion pair in the IL phase (m water ) increased dramatically upon cooling. The temperature dependence of this parameter was found to be useful to predict the possibility of the ILs to show the LCST-type phase behaviour after mixing with water. Since the value of m water depended on the ion structure, especially on the hydrophobicity, the T c was accurately set out by suitably mixing two ILs with different hydrophobicity.

Gastrointestinal stromal tumor (GIST) is a mesenchymal tumor of the gastrointestinal tract. Mutation of KIT and PDGFRA genes is implicated in the tumorigenesis. Approximately 10% of GISTs do not harbor mutation of these genes, and they are designated as "wild type" GIST. They are classified into succinate dehydrogenase (SDH)-deficient and non-SDH-deficient groups. SDH-deficient group includes Carney triad and Carney Stratakis syndrome. The patients are young women. Tumors occur in the antrum of the stomach, and tumor cells are epithelioid. Lymph node metastasis is frequent. The non-SDH-deficient group includes neurofibromatosis (NF) type 1 and GISTs with mutations of BRAF, KRAS, and PIK3CA and with the ETV6-NTRK3 fusion gene. GIST in NF occurs in the small intestine, and tumor cells are spindle shaped. GIST with BRAF mutation arises in the small intestine. Attention to the age, gender, family history and other neoplasms may raise the prediction of syndromic disease. Location of the tumor, morphology, and pleomorphism of the tumor cells are further informative. Lymphovascular invasion should be carefully evaluated. The determination of KIT expression is essential for the diagnosis. When wild type GIST is suspected, intensive genetic analysis is required. Further, a careful and long-time observation is recommended.

A mixture of tetrabutylphosphonium N-trifluoromethanesulfonyl leucine and water showed a reversible change between a homogeneous phase and separated liquid-liquid phase by bubbling CO(2) gas or N(2) gas at atmospheric pressure as well as a small temperature change.

Molecular orientation is one of the most crucial factors to boost the efficiency of organic light-emitting devices. However, active control of molecular orientation of the emitter molecule by the host molecule is rarely realized so far, and the underlying mechanism is under discussion. Here, we systematically investigated the molecular orientations of thermally activated delayed fluorescence (TADF) emitters in a series of carbazole-based host materials. Enhanced horizontal orientation of the TADF emitters was achieved. The degree of enhancement observed was dependent on the host material used. Consequently, our results indicate that π-π stacking, CH/n (n = O, N) weak hydrogen bonds, and multiple CH/π contacts greatly induce horizontal orientation of the TADF emitters in addition to the molecular shape anisotropy. Finally, we fabricated TADF-based organic light-emitting devices with an external quantum efficiency (η ext) of 26% using an emission layer with horizontal orientation ratio () of 79%, which is higher than that of an almost randomly oriented emission layer with of 62% (η ext = 22%).

A 1,4-azaborine derivative fused by two naphthalene rings, a dinaphthoazaborine was synthesized, and its molecular structure was revealed by X-ray crystallographic analysis. UV–vis absorption and fluorescence spectra of the dinaphthoazaborine indicated a decrease in the HOMO–LUMO energy gap compared with that of dibenzoazaborines. Electrochemical measurements elucidated the enhanced electron-accepting characteristics of the dinaphthoazaborine.

In this study, we synthesized and characterized multiresonant thermally activated delayed fluorescent (TADF) materials embedded with nitrogen-boron-oxygen (NÀ BÀ O), exhibiting color-tunability between blue and green, namely NBO, m-DiNBO, and p-DiNBO. The three emitter materials showed a high photoluminescence quantum yield (PLQY) and a state-of-the-art narrow full width at half maximum (FWHM) of 96 %/25 nm, 87 %/17 nm, and 99 %/19 nm, respectively. For m-DiNBO and p-DiNBO, the emission color could be tuned from blue to green by regulating the nonbonding/bonding molecular orbital characters. Owing to the expanded planar molecular structure, m-DiNBO and p-DiNBO showed high horizontal dipole ratio (Θ) of 88 % and 92 %, respectively. OLEDs were prepared with NBO, m-DiNBO, and p-DiNBO, exhibiting high external quantum efficiencies of 16.8 %, 24.2 %, and 21.6 %, respectively. NBO and m-DiNBO exhibited pure-blue emission with CIE coordinates of (0.137, 0.142) and (0.126, 0.098), respectively. p-DiNBO showed pure-green emission with a CIE coordinate of (0.258, 0.665).

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