Among the large family of metal-organic frameworks (MOFs), Zr-based MOFs, which exhibit rich structure types, outstanding stability, intriguing properties and functions, are foreseen as one of the most promising MOF materials for practical applications. Although this specific type of MOF is still in its early stage of development, significant progress has been made in recent years. Herein, advances in Zr-MOFs since 2008 are summarized and reviewed from three aspects: design and synthesis, structure, and applications. Four synthesis strategies implemented in building and/or modifying Zr-MOFs as well as their scale-up preparation under green and industrially feasible conditions are illustrated first. Zr-MOFs with various structural types are then classified and discussed in terms of different Zr-based secondary building units and organic ligands. Finally, applications of Zr-MOFs in catalysis, molecule adsorption and separation, drug delivery, and fluorescence sensing, and as porous carriers are highlighted. Such a review based on a specific type of MOF is expected to provide guidance for the in-depth investigation of MOFs towards practical applications.

Flowering of many plants is induced by environmental signals, but these responses can depend on the age of the plant. Exposure of Arabidopsis thaliana to vernalization (winter temperatures) at germination induces flowering, whereas a close perennial relative Arabis alpina only responds if exposed when at least 5 weeks old. We show that vernalization of these older A. alpina plants reduces expression of the floral repressor PEP1 and activates the orthologs of the Arabidopsis flowering genes SOC1 (Aa SOC1) and LFY (Aa LFY). By contrast, when younger plants are vernalized, PEP1 and Aa SOC1 mRNA levels change as in older plants, but Aa LFY is not expressed. We demonstrate that A. alpina TFL1 (Aa TFL1) blocks flowering and prevents Aa LFY expression when young plants are exposed to vernalization. In addition, in older plants, Aa TFL1 increases the duration of vernalization required for Aa LFY expression and flowering. Aa TFL1 has similar functions in axillary shoots, thus ensuring that following a flowering episode vegetative branches are maintained to continue the perennial life cycle. We propose that Aa TFL1 blocks flowering of young plants exposed to vernalization by setting a threshold for a flowering pathway that is increased in activity as the shoot ages, thus contributing to several perennial traits.

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Two 2:2 types of monolanthanide substituted polyoxometalates [{(R-PW 11 O 39 H)Ln(H 2 O) 3 } 2 ] 6-(Ln=Nd III for 1 and Gd III for 2) and [{(R-PW 11 O 39 )Ln(H 2 O)(η 2 ,μ-1,1)-CH 3 COO} 2 ] 10-(Ln=Sm III for 3, Eu III for 4, Gd III for 5, Tb III for 6, Ho III for 7 and Er III for 8) have been synthesized in aqueous solution and characterized by elemental analyses, IR spectra, UV-vis-NIR spectra, thermogravimatric analyses and single-crystal X-ray diffraction. The common structural features are that they are constructed from monovacant Keggin-type polyoxoanions [R-PW 11 O 39 ] 7and trivalent lanthanide cations. Both 1 and 2 are essentially isomorphous, and the molecular structure is built by two symmetrically related monolanthanide substituted Keggin units [R-PW 11 O 39 Ln(H 2 O) 3 ] 4linked via two Ln-O-W bridges, representing the first monovacant Keggin polyoxotungstate dimers constituted by two [R-PW 11 O 39 ] 7polyoxoanions and two lanthanide cations in polyoxometalate chemistry. 3-8 are also isostructural and display another dimeric structure constructed from two monolanthanide substituted units [(R-PW 11 O 39 )Ln(H 2 O)(η 2 ,μ-1,1)-CH 3 COO] 5bridged by two (η 2 ,μ-1,1)-acetato ligands. The photoluminescence properties of 4 and 6 were investigated at room temperature. Magnetic susceptibility measurements of 1, 3, 4, 7 and 8 between 2 and 300 K exhibit that their magnetic behaviors mainly result from the spin-orbital coupling interactions as well as weak antiferromagnetic exchange interactions within magnetic centers. The electrochemical properties of 1, 3, 4, 5, 7 and 8 were studied by means of cyclic voltammetry in aqueous solution with 0.5 M Na 2 SO 4 as supporting electrolyte.

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A certain amount of Na2S2O3·5H2O solution added to the solution containing cadmium ions to form Cd/CdS photocatalysts could remove cadmium ions and produce hydrogen efficiently under visible light irradiation.

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