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In this work, a microporous Pb(II)-based framework (FJI-H22) has been synthesized upon solvothermal reaction, which is constructed from two kinds of rarely seen tetranuclear Pb(II) clusters. FJI-H22 has two kinds of one-dimensional microporous channels (ca. 12.80 A × 15.08 and 6.05 A × 11.83 A) along the crystallographic b axis. Interestingly, when immersed in methanol FJI-H22 can undergo reverse single-crystal-to-single-crystal transformations to form FJI-H22-MeOH. In particular, high stability (stable up to 300 °C in atmosphere), large Brunauer–Emmett–Teller (BET) surface area (483 m2·g–1), and the nature of microporosity enable desolvated FJI-H22 to be a good candidate for purification of natural gas. As anticipated, desolvated FJI-H22 can selectively adsorb C2/C3 hydrocarbons over CH4 at 298 K and 1 bar. Furthermore, ideal adsorbed solution theory calculations reveal that FJI-H22 shows highly selective separation of higher hydrocarbons over CH4 under ambient conditions.

We demonstrate the successful use of Eu3+-activated core–shell–shell nanoprobes for in vitro upconverting/downshifting luminescent detection of a cancer biomarker of alpha-fetoprotein., Trivalent europium (Eu3+) doped inorganic nanoparticles (NPs), emerging as a new class of red luminescent nanoprobes, have shown great promise in bioapplications as diverse as luminescent bioassays and disease theranostics owing to their superior optical properties such as long-lived downshifting luminescence (DSL) and upconverting luminescence (UCL). However, the exploration of Eu3+-doped NPs as red luminescent bioprobes particularly combined with DSL and UCL of Eu3+ hitherto remains untouched. Herein, we report a rational core–shell–shell (CSS) design strategy to construct Eu3+-activated NaGdF4:Yb/Tm@NaGdF4:Eu@NaEuF4 CSS NPs functionalized with efficient UCL and dissolution-enhanced DSL of Eu3+ for in vitro tumor marker detection and tumor-targeted imaging. By utilizing the CSS NPs as red luminescent nanoprobes, we demonstrate the successful UCL and DSL bioassays of a typical hepatic carcinoma biomarker, alpha-fetoprotein (AFP), in human serum samples. The UCL bioassay shows a limit of detection (LOD) of AFP down to 20 pg mL–1 (290 fM), which is the lowest among luminescent bioassays of AFP ever reported, and a 30-fold improvement relative to that of the commercial dissociation-enhanced lanthanide fluoroimmunoassay kit. Meanwhile the DSL bioassay, by employing the identical CSS NPs, can serve as a self-referential validation for the reliability and accuracy of the UCL bioassay for AFP detection. Furthermore, these CSS NPs can also function well in tumor-targeted UCL bioimaging, thereby revealing the great promise of the designed CSS NPs as red luminescent bioprobes in ultrasensitive in vitro detection of tumor markers in clinical diagnosis.

A metal–organic framework with high adsorption and selectivity for reversible uptake of Cd(ii) was developed. Both fast detection of Cd(ii) at low concentration and in situ reconstruction of the used MOF were successfully achieved., An extraordinary metal–organic framework FJI-H9 with high adsorption and selectivity for the reversible uptake of Cd(ii) has been developed. Further research indicates that such high absorption results from an unusual synergy from active sites and the confined cavity. In addition, fast detection of Cd(ii) at low concentrations down to 10 ppm and in situ reconstruction of the used framework into a fresh one have also been successfully achieved.

Four isostructural lanthanide(III) complexes, [Ln2(HL)2(H2O)4]n·2nH2O (H4L = 3,3′,6,6′-tetracarboxyl-2,2′-bipyridine) (Sm (1), Eu (2), Gd (3), Tb (4)), have been synthesized under the hydrothermal condition and characterized by single-crystal X-ray diffractions, powder X-ray diffractions (PXRD), thermal analyses (TGA) and elemental analyses (EA). These four complexes all exhibit 1D chain-like structures containing di-nuclear lanthanide(III) units, which are further linked by hydrogen bonding into 3D supramolecules. To further investigate the properties of the above complexes, the photoluminescent properties of 2 and 4 are also discussed.

Methyl 3-deoxy-3-(diphenylphosphino)-4,6-O-benzylidene-α-D-altropyranoside (1) and methyl 2-deoxy-2-(diphenylphosphino)-4,6-O-benzylidene-α-D-altropyranoside (2) were prepared from methyl 2,3-anhydro-4,6-O-benzylidene-O-D-mannopyranoside and methyl 2,3-anhydro-4,6-O-benzylidene-α-D-allopyranoside, respectively, via regioselective and stereospecific ring-opening reactions in high yields. Compounds 1 and 2 were oxidized to give the corresponding phosphine oxides (S and 4).

The title complex, [La(btec)1/2(H2btec)1/2 (H2O)]n (H4btec= 1, 2,4,5-benzenetetracarboxylic acid) (1) was synthesized by the hydrothermal reaction of 1,2,4,5-benzenetetracarboxylic dianhydride with La(NO3)3·6H2O in H2O, and crystallizes in the triclinic system, space group P-1 with a = 0.64403(3) nm, b = 0.94500(4) nm, c = 0.96380(5) nm, a = 88.535(2)°, β = 100.314(2)°, γ = 76.6470(10)°, V = 1.60968(10) nm3, Z = 2, and final R = 0.0274, Rw = 0.0735. In 1, each La(m) ion is coordinated by eight oxygen atoms from six carboxylate groups and one coordinated water molecule. Two different coordination modes of H4btec were present in the structure, one of which contains two protonated carboxylate groups to balance the charge.

A penta-coordinated Cu(II) complex with mixed ligands 4, 4′-bipyridine (4,4′-bpy) and 2-pyrazine-5-carboxylate anion (2-pzc), [Cu(4,4′-bpy)(2-pzc)(H2O)]CIO4·HzO (1), has been solvothermally synthesized and characterized. Complex 1 crystallizes in the monoclinic space group P21/n with a = 0.82996(2) nm, b = 1.58156(5) nm, c = 1.53837(1) nm, β = 103.536(2)°, V = 1.96322(8) nm3, Mr = 478.30, Z = 4, Dc = 1.618 g/cm3, final R = 0.0544 and wR = 0.1487. The Structure of 1 indicates that the central Cu(II) atom is penta-coordinated by two N atoms from two 4,4′-bpy ligands, and one N atom and one oxygen atom of the 2-pzc ligand in the equatorial plane, and one oxygen atom of the coordinated water molecule at the axial position. The coordination geometry of Cu(II) atom could be considered as a slightly distorted square-pyramidal environment. The 4, 4′-bpy ligands bridge the Cu(II) centers to form a one-dimensional chain, and 2-pzc acts as a terminal chelated ligand, and #±# interaction between the pyrazine rings of 2-pzc ligands of adjacent chains links the chains into a 2D sheet. Furthermore, the hydrogen bonds among the oxygen atoms of the uncoordinated water molecules and the N atoms and O atoms of 2-pzc ligands and the oxygen atoms of the coordinated water molecules link the sheets into the ultimate 3D network of complex 1.

Ba 0.55 Sr 0.45 TiO 3 (BST) precursors were synthesized via a polyvinyl alcohol (PVA) modified sol-precipitation route. And the obtained precursors were then calcined in air at temperatures ranging from 400 to 800 °C. The formation mechanism of BST phase was investigated using X-ray diffraction (XRD), while the effect of PVA on the particle morphology of the BST phase was studied by using scanning electron microscopy (SEM). The results show that the introduction of PVA significantly affects the morphology of the BST powders. High purity nanocrystalline powders were synthesized by calcination of the BST precursors encapsulated by PVA gel, with narrow particle distribution (30–80 nm) and being nearly free of agglomeration. While, large particles (40–170 nm) with evident agglomeration were obtained from the solution without PVA.

Compounds (Et4N)2[MCu3S4(dtcR2)3] (M=W (1) or Mo (2); R2  C5H10 (a), Et2 (b) or C4H8 (c) were synthesized by the reaction of (Et4N)2MS4 and CuCl in the presence of NadtcR2 in DMF. The crystal and molecular structures of 1a·DMF and 2a·DMF were determined from X-ray diffraction data. The compounds are isomorphous and crystallize in the triclinic space group P 1 with unit cell parameters for 1a(2a)·DMF: a=12.047(0) (12.053(2)), b= 17.620(3) (17.650(5)), c=14.514(1) (14.533(4)) A; α=100.83(9) (100.43(3)), β=115.41(3) (115.47(2)), γ=79.49(8) (79.78(2))°; V=2715.9 (2727.8) A3, Z=2 (2), and Dx=1.611 (1.497) g/cm3. The final R values converged to 0.048 and 0.067 for M=W and Mo respectively. [p ]The four metal atoms MCu3 are coplanar with the central tetrahedron of MS4 preserved. Each Cu(I) ion is coordinated to two inorganic S atoms from MS4 and two organic S atoms from one dtcC5H10 ligand in a distorted tetrahedral geometry. Infrared spectra showed two stretching vibrations at 430–442 cm− for μ3-SM and 455–463 cm−1 for μ2-SM. The compounds are diamagnetic and show reversible one-electron oxidation-reduction at E1/2 = 0.55 V (2a).

We report the synthesis and structure of a novel cluster compound (Et 4 N) 2 [W 2 Cu 5 S 8 (S 2 CNMe 2 ) 3 ] consisting of two defective cubane cores, WCu 2 S 4 and WCu 3 S 4 , bridged by two Me 2 dtc − ligands and jointed by two weak Cu-S bonds

The reaction system of [Et 4 N] 2 MoSe 4 , FeCl 2 and R 2 NCS 2 Na in DMF-CH 3 CN at ambient temperature yielded the Mo-Fe-Se cluster compounds MoFe 3 Se 4 (m-R 2 NCS 2 ) 2 (R 2 NCS 2 ) 4 (R 2 =Me 2 (1), Et 2 (2), C 4 H 8 (3)) with MoFe 3 Se 4 core. X-ray diffraction analyses of 2 revealed that the molecular structure contains a distorted cubane like M 4 Se 4 core with two bridged and four chelated Et 2 NCS 2 - ligands. The cyclic voltammetric studies of the compounds showed the reversible multielectrontransfer sequence.