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Intriguing 1D single-walled metal–organic nanotubes (MONTs) Zn2(RR-CHCAIP)Py2(H2O) (HMOF-2) were successfully self-assembled using a semirigid homochiral ligand, 5,5′-((1R,2R)-cyclohexane dicarbonyl bis(azanediyl)) diisophthalic acid (RR-CHCAIP) with zinc salt, which was constructed from an organic ligand similar to the twin blades of a propeller with the Zn2(COO)4(H2O)(Py)2 cluster acted as the SBU, and the terminal pyridine auxiliary ligand capping at the Zn atoms played a key role in the formation of the 1D single nanotubes. The fluorescence of the HMOF-2 emulsion could be effectively quenched by D/L-lactic acid, D/L-tartaric acid enantiomers and D/L-alanine via hydrogen bonding interactions with the inwall of MONTs, which suggested this to be a remarkable chiral sensor for α-hydroxyl carboxylic acid and amino acid enantiomers with good sensitivity and enantioselectivity. Comparatively, HMOF-2 showed a negligible response towards D/L-mandelic acid and D/L-tyrosine, which chiefly arose from the confinement effect and the host–guest interaction of MONTs with the analytes. The construction strategy of MONTs based on the homochiral propeller-like ligand that bridges two metallic pillars will open new perspectives for developing self-assembling chiral MONTs with unique and practically useful enantioselective functions.

The design of white-light phosphors is attractive in solid-state lighting (SSL) and related fields. A new strategy in obtaining white light emission (WLE) from dual-way photon energy conversion in a series of dye@MOF (LIFM-WZ-6) systems is presented. Besides the traditional UV-excited one-photon absorption (OPA) pathway, white-light modulation can also be gained from the combination of NIR-excited green and red emissions of MOF backbone and encapsulated dyes via two-photon absorption (TPA) pathway. As a result, down-conversion OPA white light was obtained for RhB+ @LIFM-WZ-6 (0.1 wt %), BR-2+ @LIFM-WZ-6 (2 wt %), and APFG+ @LIFM-WZ-6 (0.1 wt %) samples under 365 nm excitation. RhB+ @LIFM-WZ-6 (0.05 wt %), BR-2+ @LIFM-WZ-6 (1 wt %) and APFG+ @LIFM-WZ-6 (0.05 wt %) exhibit up-conversion TPA white light under the excitation of 800, 790, and 730 nm, respectively. This new WLE generation strategy combines different photon energy conversion mechanisms together.

Two-dimensional (2D) metal-organic frameworks (MOFs) have attracted growing interest due to excellent performance in gas separation, energy conversion and storage, catalysis, and sensing, but their homochirality and exfoliation as well as related enantioselective catalysis and sensing remain a stage of pending exploration owing to the scarcity of homochiral MOFs and intrinsic aggregation of nanosheets. Herein, a homochiral 2D MOF (HMOF-3) with polymeric chirality, good thermostability, and solvent stability is designed and constructed by a homochiral organic ligand 5,5'-((1R,2R)-cyclohexane dicarbonyl bis(azanediyl)) diisophthalic acid (R,R-CHCAIP), a ditopic coligand 4,4'-bipyridine, and Zn salts. Remarkably, HMOF-3 can be exfoliated via solvent-assisted sonication to achieve 2D HMOF-3 nanosheets (HMOF-3-NS), which exhibit a sensitive turn-on effect with the fluorescence enhancement up to 63.5 times in the presence of R/S-mandelic acid, d/l-tartaric acid, d/l-lactic acid, d/l-alanine, and d/l-tryptophan. More importantly, the high surface area, polymeric chirality environment, and highly accessible functional sites on the surface of HMOF-3 nanosheets enable close contact with probed enantiomers, leading to highly enantioselective and sensitive sensing. The turn-on mechanism of host-guest-assisted electronic transfer is confirmed by DFT calculation and the relative experiment. This work highlights the promise of homochiral 2D MOF nanosheets for enantioselective sensing applications.

Solvothermal reactions of lanthanide salts and a semirigid tripodal H3tatab (4,4′,4″-s-triazine-1,3,5-triyltri-p-aminobenzoic acid) ligand in mixed water and N-methyl pyrrolidone (NMP) generated novel breathing MOFs [Ln(tatab)]·solvent (Ln = Eu in 1-Eu, Tb in 1-Tb, Eu0.015Tb0.985 in 1-Eu0.015Tb0.985). The framework of 1 was contracted upon removal of guests to form partly desolvated [Ln (tatab)]·3.7H2O·2.5NMP (1′). Single-crystal X-ray analyses demonstrated that 1 has the breathing ability to spontaneously release guests and maintain the same topology. In contrast to as-synthesized 1, the cell volume of 1′ decreased markedly upon removal of the guests. Different from linear dicarboxylates, the semirigid tripodal tatab ligand is bridged to an inorganic Ln–O chain, limiting the rotation around the O–O-axis of carboxylate. The breathing mechanism is based on the flexible C–N–C angles of amide bonds in the tatab ligand, causing a change in the solvent-accessible volume in the framework. Interestingly, the luminescence color of breathing co-doped lanthanide MOF 1′-Eu0.015Tb0.985 is blue-shifted and turned from orange to green with an increase in temperature, which can be attributed to a change in the relative intensity of Tb and Eu emissions, and is quite different from that observed for the reported related compounds. The breathing co-doped lanthanide MOF 1′-Eu0.015Tb0.985 can be applied as a high-sensitivity ratiometric thermometer in a broad temperature from 90 to 300 K.

Self-assembly of zinc salt with rationally designed chiral ligand, (1R,2R)-2-(pyridine-4-ylcarbamoyl) cyclohexanecarboxylic acid (RR-PCCHC) generated 2D homochiral metal-organic framework [Zn(RR-PCCHC)2] (HMOF-1) that is composed of DNA-like right-handed double-helix structure. HMOF-1 shows high solvent and thermal stability and is also stable in neutral, weak acidic and weak basic aqueous solution. Emulsified HMOF-1 shows strong inherent circular dichroism (CD) signal in aqueous solution, which can show regular intensity change by induction of amino acids. On the basis of the measuring of CD signal intensity, a chemosensor for unmodified amino acids is fabricated, which differ from reported those in which CD signal is amplified by a complicated chemical reaction of originally CD-silent molecule with probed amino acids. This chemosensor can be used for rapid, convenient and sensitive detection of micro amount of amino acids. Most remarkably, 3 × 10-8 mol of l-aspartic acid and 4 × 10-8 mol of d-aspartic acid in aqueous solution can completely quench CD signal of emulsified HMOF-1 in H2O. It is found that the difference of recognition ability between d- and l-proline is the largest in all probed amino acids. The LOD (limit of detection) of the proposed sensor for the determination of aspartic acid is 13.31 ppm. The recognition efficiency η = [Formula: see text] × 100% for l-aspartic acid is as high as 92.1%. The interacting mechanism of DNA-like HMOF-1 with probed amino acids is similar to that of groove binding of targeting drug with DNA.

As the repaid development mobile phone and mobile internet, the mobile phone is considered as the import interface between brands and consumers by managers. Mobile advertising, Mobile advertising, which is defined as any form of marketing, advertising or sales promotion activity aimed at consumers and conducted over a mobile channel, is becoming the new promising marketing channel. Mobile advertising is getting more and more sophisticated. Thus, how to apply mobile advertising to increase advertising effect is an important challenge for CMOs. To help the CMO to understand the mobile advertising, this paper reviewed recent advances in mobile advertising researches.

Near-UV single-phase white-light phosphor (Eu0.045Tb0.955CPOMBA/La0.6Eu0.1Tb0.3CPOMBA) based on metal-organic framework was prepared by in situ doping isostructural lanthanide MOF with Eu(3+) and Tb(3+), and it is found that the energy can effectively transfer from organic ligand to lanthanides, which can overcome weak absorption under direct excitation of lanthanide ions due to the forbidden f-f transitions. The photoluminescence and thermostability of the new MOF phosphor are investigated, and effective white-light emission is achieved under 365 and 380 nm excitations. By employing Eu0.045Tb0.955CPOMBA as phosphor, we fabricated a near-ultraviolet white-light-emitting diode (n-UV WLED) (365 nm) with low CCT (5733 K), high CRI (Ra = 73.4), and CIE chromaticity coordinate (0.3264, 0.3427). This approach may open new perspectives for developing single-phase UV phosphors.

The synthesis of fifteen new N-glycosyl-N'-(4-arylthiazol-2-yl) aminoguanidines is described. Some of the synthesized guanidines displayed inhibitory activity against NOS or anti-HIV-1 PR activity. The structure of all new compounds was confirmed by MS, IR and 1 H NMR spectral data and elemental analyses.

A series of novel N-glycosyl-N'-pyrazolylmethylene aminothioureas (4a-4e, 5a-5e) were synthesized from N-glycosyl-N'-aminothioureas (2a-2d) and 4-formylpyrazole (3a-3e). Activated 4A molecular sieves were adopted for dehydrated reagent to improve the reaction rate and yield. The structures of the new compounds were identified on the basis of IR, 1 H NMR and MS spectra. Simultaneously, the compounds were detected by fluorescence spectrophotometer and had preferable fluorescence activity, so they can be selected as a kind of novel fluorescence labeled derivative of sugar.