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Nonlocal nonlinear Schrödinger equations are among the important models of nonlocal integrable systems. This paper aims to present a general formula for arbitrary-order breather solutions to multi-component nonlocal nonlinear Schrödinger equations by using the Hirota bilinear method. In particular, abundant wave solutions of two- and three-component nonlocal nonlinear Schrödinger equations, including periodic and mixed-wave solutions, are obtained by taking appropriate values for the involved parameters in the general solution formula. Moreover, diverse wave structures of the resulting breather and periodic wave solutions with different parameters are discussed in detail. [ABSTRACT FROM AUTHOR]

The movement speed of Typhoon In-Fa (2021) was notably slow, at 10 km h-1 or less, for over 20 hours following its landfall in Zhejiang, China, in contrast to other typhoons that have made landfall. This study examines the factors contributing to the slow movement of Typhoon In-Fa, including the steering flow, diabatic heating, vertical wind shear (VWS), and surface synoptic situation, by comparing it with Typhoons Yagi (2018) and Rumbia (2018) which followed similar tracks. The findings reveal that the movement speed of Typhoons Yagi and Rumbia is most closely associated with their respective 500 hPa environmental winds, with a steering flow of 10-12 m s-1. In contrast, Typhoon In-Fa's movement speed is most strongly correlated with the 850 hPa environmental wind field, with a steering flow speed of only 2 m s-1. Furthermore, as Typhoon In-Fa moves northwest after landfall, its intensity is slightly greater than that of Typhoons Yagi and Rumbia, and the pressure gradient in front of Typhoon In-Fa is notably smaller, leading to its slow movement. Additionally, the precipitation distribution of Typhoon In-Fa differs from that of the other two typhoons, resulting in a weak asymmetry of wavenumber-1 diabatic heating, which indirectly affects its movement speed. Further analysis indicates that VWS can alter the typhoon's structure, weaken its intensity, and ultimately impact its movement. [ABSTRACT FROM AUTHOR]

Two structurally similar columnar ZnII-MOFs {[Zn8L4(TZ)4·0.5H2O]·4[Me2NH2]·6DMF·4H2O}n (Zn-MOF1) and {[Zn4L2(MT)2·H2O]·2[Me2NH2]·4DMF·4H2O}n (Zn-MOF2) were synthesized with irregular ligands, 2,2′-(pyridine-2,6-diyl) diterephthalic acid (H4L), 1,2,4-triazolium (TZ) and 1H-1,2,4-triazole-3-thiol (MT). Structural studies showed that both ZnII-MOFs had a similar 3D framework constructed with multiple SBUs and displayed an unusual (3,4,6)-connection topology. Furthermore, both ZnII-MOFs have high performance in gas adsorption and separation. The separation ratios of C2H2/CH4 and CO2/CH4 of Zn-MOF1 were 15.1 and 6.8, respectively, and those of Zn-MOF2 were 14.6 and 6.5, respectively. Moreover, Eu@Zn-MOF1 and Eu@Zn-MOF2 were successfully obtained by adding Eu3+ ions to the synthesis system. After a series of fluorescence tests, these two MOFs were found to have good fluorescence performance, and showed high selectivity and sensitivity to Fe3+ ions in aqueous solution with a low detection limit. [ABSTRACT FROM AUTHOR]

An anionic three-dimensional framework {(Me2NH2)2[Zn8(L)6(ad)4(μ4-O)]·10DMF·11H2O}(Zn-MOF, L2− = 4,4′-(3-aminopyridine-2,5-diyl)dibenzoic acid; ad− = adeninate) with a column-layered structure was synthesized. Structural studies show that the Zn-MOF has octahedral cages [Zn8(ad)4(μ4-O)], the adjacent cages are connected by O atoms to form 1D columnar SBUs, and every four SBUs are connected by L2− to form a square channel 3D framework. Gas adsorption studies show that the BET and Langmuir surface areas of Zn-MOF are 1370.31 and 1478.04 m2 g−1, respectively, and the total pore volume for single-point adsorption is 0.528 cm3 g−1. The surface of the pores of the Zn-MOF is occupied by open metal sites and uncoordinated carboxyl groups, showing good capture ability for C2H2 and good adsorption selectivity for C2H2/CH4. More importantly, the free (CH3)2NH2+ ions present in the pores of the columnar layered Zn-MOF can cation-exchange with MB, MV, and RhB ions in aqueous solution. Therefore, Zn-MOF can not only effectively adsorb the cationic dyes MB, MV, and RhB, but also exhibit particularly selective sorption towards the mixed anion and cation dyes MB/MO and MV/MO. In addition, a series of fluorescence experiments show that Zn-MOF has good fluorescence properties, exhibiting highly selective and sensitive fluorescence detection and recognition performance for Fe3+ ions in aqueous solution with a low detection limit. [ABSTRACT FROM AUTHOR]

Two porous complexes, namely, {[H2N(Me)2]2[Zn5(L)2(OH)2]·3DMF·4H2O}n (1), and {[H2N(Me)2]4[Cu3(L)2(H2O)2]·4DMF·3H2O}n (2) were solvothermally constructed based on a symmetrical V-shaped rigid multicarboxylic acid ligand H5L (H5L = 3,5-di(2′,5′-dicarboxylphenyl)benzoic acid). Complexes 1 and 2 display 3D frameworks with various metal clusters. Complex 1 is a 3D porous framework with a (4,8)-connected topology featuring a 1D pore structure in the a-axis direction with a penta-nuclear cluster [Zn5(μ2-COO)6(μ1-COO)4(μ3-O)2]. By contrast, 2 displays a 3D (3,4)-connected net based on binuclear [Cu2(COO)4] paddlewheel SBUs. Complex 1 reveals solid-state luminescent properties at ambient temperature, and the maximum emission peak was observed at ∼443 nm (λex = 339 nm). Meanwhile, 1 shows high selectivity and sensitivity not only for Fe3+ cations but also for Cr2O72− anions via the luminescence quenching effect with a low detection limit, which thus could be a potential crystalline material for detecting these substances. The mechanisms of the quenching effect and sensing properties of 1 were discussed in detail. [ABSTRACT FROM AUTHOR]