The removal of C2H2 and C2H6 from C2H4 streams is of great significance for feedstock purification to produce polyethylene and other commodity chemicals but the simultaneous adsorption of C2H6 and C2H2 over C2H4 from a ternary mixture has never been realized. Herein, a robust metal–organic framework, TJT‐100, was designed and synthesized, which demonstrates remarkably selective adsorption of C2H2 and C2H6 over C2H4. Breakthrough experiments show that TJT‐100 can be used as an adsorbent for high‐performance purification of C2H4 from a ternary mixture of C2H2/C2H4/C2H6 (0.5:99:0.5) to afford a C2H4 purity greater than 99.997 %, beyond that required for ethylene polymerization. Computational studies reveal that the uncoordinated carboxylate oxygen atoms and coordinated water molecules pointing towards the pore can trap C2H2 and C2H6 through the formation of multiple C−H⋅⋅⋅O electrostatic interactions, while the corresponding C2H4–framework interaction is unfavorable.

The removal of C2H2 and C2H6 from C2H4 streams is of great significance for feedstock purification to produce polyethylene and other commodity chemicals but the simultaneous adsorption of C2H6 and C2H2 over C2H4 from a ternary mixture has never been realized. Herein, a robust metal–organic framework, TJT‐100, was designed and synthesized, which demonstrates remarkably selective adsorption of C2H2 and C2H6 over C2H4. Breakthrough experiments show that TJT‐100 can be used as an adsorbent for high‐performance purification of C2H4 from a ternary mixture of C2H2/C2H4/C2H6 (0.5:99:0.5) to afford a C2H4 purity greater than 99.997 %, beyond that required for ethylene polymerization. Computational studies reveal that the uncoordinated carboxylate oxygen atoms and coordinated water molecules pointing towards the pore can trap C2H2 and C2H6 through the formation of multiple C−H⋅⋅⋅O electrostatic interactions, while the corresponding C2H4–framework interaction is unfavorable.

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Two robust metal-organic frameworks (MOFs), {H[Ni(π-HO)][Ni(rt-HO)]Ni(Tri)}[VWO]·24HO (1) and {H[Ni(π-O)][Ni(rt-HO)]Ni(Tri)}[VWVOV][VWVOV]·24HO (2) (Tri = 1,2,4-triazole), composed of polyoxometalates (POMs) and metal-organic units, were designed and synthesized by a hydrothermal method. Structure analysis indicates that there is a metal-organic crown [{Ni(Tri)(HO)}] ({Ni}) in these two compounds. In 1, the {Ni} crown embraces four pendant Tri ligands that could capture a cationic [Ni(HO)] group, resulting in the Ni-Tri building unit [Ni(HO){Ni(Tri)(HO)}] ({Ni}). The {Ni} building unit was fused together by Tri bridges into the 2D metal-organic layers, which are pillared by a typical Keggin-type POM [VWO] to construct a 3D supramolecular framework via the hydrogen bonds. Interestingly, the 2D metal-organic layer in 1 was successfully transferred into a 3D covalent MOF via extension of the length of the pillars by capping a Keggin-type POM with V-O units. Moreover, electrochemical behaviors and electrocatalytic properties of these two compounds were both studied, which can act as bifunctional electrocatalysts toward the reduction of HO and oxidation of nitrite in neutral aqueous solution.

The rheological properties of aqueous solutions of a cationic surfactant, 3-hexadecyloxy-2-hydroxypropyl trimethyl ammonium bromide (R 16 HTAB), and its mixed solution system with sodium salicylate (NaSal) have been studied by using steady state and frequency sweep rheological measurements. The microstructure of the formed wormlike micelles has been ascertained by transmission electronic microscopy and 1 H NMR technology. The effects of the surfactant concentration, added salt, temperature and different counterions on the viscoelastic solutions have been systematically investigated. In a salt-free state, the h 0 and R 16 HTAB concentrations obey the relationship of the power law, i.e. h 0 f C 2.53 , in the examined concentration range. The addition of NaSal greatly promoted the micellar growth in R 16 HTAB aqueous solution and resulted in the generation of wormlike micelles. The causes of the formation of wormlike micelles and the strong network structure have been analyzed.

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Two series of lanthanide-based metal-organic frameworks, {[Ln(BIPA-TC)0.5(DMA)2(NO3)]·DMA·H2O}n (1-Ln, Ln = Eu, Dy, Sm, Nd) and {[Ln2(BIPA-TC)1.5(DMA)3(H2O)2]·2DMA·2H2O}n (2-Ln, Ln = Eu, Dy, Sm, Nd), were successfully constructed via solvent regulation strategy...

Two new complexes [Co(H2O)6 Co8(L1)12]X6 x n H2O (X = NO3(-), n = 12 (1); X = HCO3-, n = 24, (2); HL1 = 4,6-bis(2-pyridyl)-1,3,5-triazin-2-ol) have been synthesized and characterized by single-crystal X-ray diffraction. A [Co(H2O)6](2+) ion is encapsuled in the central cavity of the cubelike nanocage [Co(H2O)6 Co8(L1)12](6+) cation, assembled by eight cobalt ions at the corners and twelve bis-bidentate ligands L1 as the edges, via the formation of 12-fold strong hydrogen bonds between the six coordinated water molecules and the oxygen atoms of twelve L1 as a guest. Complex 1 crystallizes in a centrosymmetric space group P1, while 2 is in a very high symmetric space group Im3. In 2, a planar [(HCO3)2](2-) dimer motif R2(2)(8) synthon plus six lattice water molecules constitute a planar supramolecular synthon R8(8)(20), which acts as a four connector, generating a 3D hydrogen-bonded NbO net with cubelike host cavities of approximately 20 A diameter. Interestingly, the cubelike nanocage [Co(H2O)6 Co8(L1)12](6+) cations fill in the cavities as templates. The magnetic properties of 1 have also been studied in the temperature range of 2-300 K, and its magnetic susceptibility obeys the Curie-Weiss law, showing antiferromagnetic coupling.