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The effects of γ-ray irradiation on the lipophilic and hydrophobic properties of two types of polypropylene (PP) foam materials were systematically studied. Isotactic polypropylene (iPP) and high-melt-strength polypropylene (HMSPP) sheets were prepared by hot pressing with a thickness of 1 mm, and then PP foams were prepared by supercritical CO2 batch foaming. Finally, the foamed samples were irradiated with γ-rays. The results showed that the melting points and crystallization temperatures of the two foams decreased after irradiation. The scanning electron microscope images showed that the cell walls of both PP foams appeared cracks and the roughness of the foam’s cross-section increased significantly. The water contact angle of iPP foam largely increased by 26.4%, and the contact angle of HMSPP foam increased from 135.2° to 141.8°, which almost reached the super-hydrophobic level. The enhanced roughness increased the hydrophilic defects and the droplet adhesion resistance. Moreover, the appearance of the cracks in the cell walls increased the connectivity between cells, which largely increased the foam oil absorption permeability and the oil absorption quantity. This study provides a method for preparing lipophilic and hydrophobic foam.

Metal ions widely exist in biological systems and participate in many vital biochemical processes. Monitoring and analyzing metal ions in biological systems can help reveal physiological processes and understand disease causes. There are various detection methods for metal ions, among which organic small-molecule fluorescent probes have significant advantages, such as high fluorescence quantum yield, easy modification, good biocompatibility, high sensitivity, and fast real-time detection. This review presents recent studies on fluorescent probes for alkali and alkaline earth metal ions (including Na+, K+, Ca2+, and Mg2+) in biological systems. All the candidates are organized according to their structures, and the sensing mechanisms of fluorescent probes are also highly taken into account. Finally, the challenges, trends and prospects of fluorescent probes in metal ion detection are discussed. We hope that this review can provide guidance for the development of fluorescent molecular probe-based alkali and alkaline earth metal ion detection methods in the future. [ABSTRACT FROM AUTHOR]

Silicon (Si) is proposed as a promising anode material for high-performance lithium-ion batteries (LIBs) due to its ultrahigh theoretical capacity. However, this material suffers from serious volume expansion during lithium insertion and extraction processes and even severe pulverization, so the practical commercial application of Si electrode materials still faces numerous challenges. Herein, the natural polymer konjac flour (KF) and polyvinylpyrrolidone (PVP) are used as the carbon source and the nitrogen source, respectively, to synthesize Si/SiOx/N–C composites by a scalable sol–gel method and one-step pyrolysis. Benefiting from the strong interfacial adhesion between the Si/SiOx nanoparticles and KF, the Si/SiOx nanoparticles are well embedded into the nitrogen-doped carbon layers after carbonization. Moreover, the SiOx buffer layers can effectively alleviate the volume change of Si during the cycling process. As an anode material for LIBs, the Si/SiOx/N–C composite exhibits an outstanding cycling performance (952 mA h g−1 after 100th cycles at 200 mA g−1) and a high capacity retention ratio (91.7%). These results suggest that this superior anode material synthesized by a simple and scalable method has potential application in LIBs. [ABSTRACT FROM AUTHOR]

A series of 6-amino-8-aryl-3,4-dihydro-1 H-spiro[naphthalene-2,2'-[1,3] dioxolane]-5,7-dicarbonitrile and 8-arylidene-4-aryl-7,8-dihydro-5 H-spiro[quinazoline-6,2'-[1,3] dioxolan]-2-amine derivatives have been synthesized from the reactions of 1,4-dioxaspiro[4.5] decan-8-one, aromatic aldehydes, and malononitrile (or guanidine carbonate) under different conditions with high yields. In this research, it was found the DBU-THF was efficient reaction condition for obtaining 6-amino-8-aryl-3,4-dihydro-1 H-spiro[naphthalene-2,2'-[1,3]dioxolane]-5,7-dicarbonitrile derivatives, while 95% EtOH and NaOH was the preferred condition for the synthesis of 8-rylidene-4-aryl-7,8-dihydro-5 H-spiro[quinazoline-6,2'-[1,3]dioxolan]-2-amine derivatives. To the best of our knowledge, these Spiroheterocycles were first reported in our research. The other advantages of this process were short-reaction time, wide scope substrates, and simple set-up. [ABSTRACT FROM AUTHOR]

An efficient and facile method for the synthesis of 5-arylindeno[2′,1′:5,6]pyrido[2,3-d] pyrimidine-2,4(3H)-dione and 7-arylbenzo[h]pyrimido[4,5-b]quinoline-8,10(5H,9H)-dione derivatives from the reactions of 2-arylidene-2,3-dihydroinden-1-one (or 2-arylidene-3,4- dihydronaphthalen-1(2H)-one) and 6-amino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione under mild conditions was described. This is a simple, efficient, and very rapid synthetic method, which is believed to provide a useful process for the synthesis of these fused heterocyclic compounds. The products were confirmed by infrared,1H NMR,13C NMR, and high-resolution mass spectrometry. [ABSTRACT FROM PUBLISHER]

A series of 5-(thiophene-2-carbonyl)-6-(trifluoromethyl)-tetrahydropyrimidin-2(1 H)-one and 6-(thiophen-2-yl)-4,5-dihydropyrimidin-2(1 H)-one derivatives have been synthesized from the reactions of aromatic aldehydes, 4,4,4-trifluoro-1-(thien-2-yl)butane-1,3-dione and urea under the different conditions with high yields. In this research, it was found that the p-toluenesulfonic acid was an efficient catalyst for obtaining 5-(thiophene-2-carbonyl)-6-(trifluoromethyl)-tetrahydropyrimidin-2(1 H)-one derivative. At the same time, solvent-free and NaOH were the preferred conditions for the synthesis of 6-(thiophen-2-yl)-4,5-dihydropyrimidin-2(1 H)-one derivative. Moreover, because of short reaction time, excellent yields, simple setup, this research offered an efficient process for preparing these kind compounds. [ABSTRACT FROM AUTHOR]

An efficient and facile synthesis of 5-amino-2,3-dihydrobenzo[ b]thiophene-4,6-dicarbonitrile and 5-amino-2,3-dihydrobenzo[ d]thiazole-4,6-dicarbonitrile derivatives from the reactions of aldehyde, malononitrile, and dihydrothiophen-3(2 H)-one or rhodanine has been reported. This is the first reported method for preparation of these compounds containing sulfur 2,6-dicyanoanilines. The compounds were confirmed by IR, H NMR, C NMR, and HRMS. The other advantages of this procure are simple handling, high yields, and short reaction times. [ABSTRACT FROM AUTHOR]