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Developing porous materials for purification of acetylene is of great significance, but remains challenging. Currently, the use of metal-organic frameworks (MOFs) for gas adsorption separation has received substantial research interest. Herein, based on the tetracarboxylic acid ligand H 4 TPTA ([1,1':3′,1″-terphenyl]-4,4′,4″,6′-tetracarboxylic acid), two MOFs (ErTPTA and CdTPTA) constructed by trinuclear cluster secondly building units (SBUs) have been successfully synthesized. They are three dimensional (3D) framework with 1D rhomboid channels, demonstrating a (4,8)-connected scu network. A series of gas adsorption tests were performed and the both compounds exhibited outstanding gas selective adsorption performance. Accordingly, the ideal adsorption solution theory (IAST) is used to simulate the adsorption selectivity, the selectivity of CdTPTA for CO 2 /CH 4 is 11.85 (0.5:0.5) and 17.02 (0.05:0.95), and for C 2 H 2 /CH 4 is 11.81 (0.5:0.5); the selectivity of ErTPTA for C 2 H 2 /CO 2 is 4.45 (0.5:0.5). Two novel MOFs were constructed by multinuclear SBUs and H4TPTA ligand, which exhibits good gas adsorption and separation performance. [Display omitted] • Two novel MOFs (ErTPTA and CdTPTA) were constructed by multinuclear SBUs and ligands. • ErTPTA and CdTPTA showed good C 2 H 2 adsorption capacity over CO 2 and CH 4. • ErTPTA exhibited high selectivity for C 2 H 2 /CO 2 , and CdTPTA showed good ability to separate CO 2 /CH 4. [ABSTRACT FROM AUTHOR]

The luminescent metal-organic framework (LMOF) materials are highly desirable applied in detection of large variety of analytes by photoluminescence method. Here, two novel isostructural LMOFs, [EuDTTA(DMF) 3 ]NO 3 and [TbDTTA(DMF) 3 ]NO 3 (EuDTTA and TbDTTA) [H 2 DTTA ​= ​2,5-di(1 H -1,2,4-triazol-1-yl) terephthalic acid], have been successfully obtained. In the structure, binuclear secondary building units (SBUs) interconnected with ligands utilizing carboxylic acid groups extend to 2D layers, and triazole functional groups of the ligands point to the interior of the pore. Based on overlap mechanism, EuDTTA and TbDTTA demonstrated excellent selective and sensitive detection of Fe3+ ion in water. The quenching constants are 3.63 ​× ​104 and 8.39 ​× ​104 ​M−1 and the detection limits are 4.14 ​× ​10−6 and 1.79 ​× ​10−6 ​M. In addition, the LMOFs exhibit good structural stability and recyclability after several fluorescence detection tests. This work provides two new LMOF materials for the research in the field of detecting metal ions. EuDTTA and TbDTTA can be used as the promising candidate luminescence sensor for detection of Fe3+ in water. Image 1 • Two-dimension LMOF materials (EuDTTA and TbDTTA) were constructed by binuclear SBUs and ligands. • The structure contains a high density of uncoordinated N atoms pointing to the pore. • Two LMOFs display excellent selective and sensitive detection of Fe3+ ion in water based on overlap mechanism. • Two LMOFs exhibit good recyclability and structural stability. [ABSTRACT FROM AUTHOR]

The North China Craton (NCC) is one of the oldest cratons in the world that preserves the records of many important geological events in the early evolution of the Earth. However, the early Precambrian tectonic evolution history of the NCC is still controversial. Here we report Paleoproterozoic leucogranites, garnet granites and granulites in the Fengzhen area that constitutes a junction between the Khondalite Belt and the Trans-North China Orogen (TNCO). The leucogranites have high SiO 2 content (75–85 wt%), and magmatic zircon U-Pb age of 2199 ± 3 Ma. Their zircons have slightly various εHf (t) values (−0.45 to 1.41) with T DM model ages of 2.5–2.6 Ga. The granites show strong LREE enrichment with La/Yb cn ratio of 12–176, and have high initial Nd isotope (ε Nd(t) = 3.5–4.5). Most of them display positive Eu anomaly, excluding fractional crystallization contribution on the high Si feature. The leucogranite was produced by melting of Late Archean felsic TTGs (tonalite–trondhjemite–granodiorite) and addition of juvenile crust. Magmatic zircons yield the garnet granite age of 2002 ± 3 Ma. The zircons show various εHf (t) values (−5.8 to 7.1) and T DM model ages (2.1–2.6 Ga). Low initial ε Nd(t) isotope value (−4.2 to −8.3) was determined in the granites. The granulites are high pressure metamorphic rocks with a peak pressure of 12.0 ± 0.8 kbar, and have similar metamorphic age of 1967 ± 10 Ma to the garnet granites. This indicates that the Fengzhen area underwent 2-Ga inter-continental orogeny, in which the melting of sedimentary rock formed the garnet granites. Similarly, sodic TTG melting to form K-rich leucogranites also needs high pressure. However, the leucogranite age is obviously older than the peak metamorphic timing of continent–continent collision. This implies that the Fengzhen area may have underwent arc-continental collision at 2.2 Ga. [ABSTRACT FROM AUTHOR]

Abstract: Six organophosphine/phosphite stabilized silver(I) complexes of 2-acetyl-1,3-indandione (2-AID) of type L n ·AgC11H7O3 (L=PPh3; n =1, 2a; n =2, 2b; L=P(OMe)3; n =1, 2c; n =2, 2d; L=P(OEt)3; n =1, 2e; n =2, 2f) have been prepared by reacting of [AgC11H7O3], which could be obtained by reacting of 2-AID with AgNO3, with triphenylphosphine, trimethylphosphite, or triethylphosphite in 1:1–2M ratio. These complexes were obtained in high yields and characterized by elemental analysis, 1H, 13C{H} NMR, IR spectroscopy, and thermal analysis (TG and DSC), respectively. The molecular structure of 2a has been determined by X-ray single crystal analysis in which the silver atom is in a distorted trigonal geometry. [Copyright &y& Elsevier]

Abstract: The effects of processing history and annealing treatment on the thermal property and polymorphic structure of nylon-6/clay nanocomposites (NCNs) have been investigated. The nanocomposites, including intercalated and exfoliated ones, were prepared by extruding nylon-6 (N6) with sodium montmorillonite (Na-MMT) or organo-montmorillonite (OMMT), respectively. DSC analysis revealed multiple melting endotherms in either the extruded or the injection-molded N6 and NCNs samples. It has been observed that a small exothermic peak around 195°C just before the lower melting peak in the skin regions. We demonstrated that this sub-T m transition was directly related to the processing-induced shear stresses. WAXD analysis was further performed to characterize the polymorphic structure of injection-molded N6 and NCNs before and after annealing. Annealing at a temperature (80°C) above the T g of N6 resulted in increase of the absolute content of γ-form in the skin regions and of the relative content of γ-form in the core regions of NCNs. In particular, annealing only leaded to increase the fraction of γ-form in the exfoliated N6/OMMT nanocomposites, which might be related to a confining effect of MMT platelet on the polymer chains mobility. [Copyright &y& Elsevier]