Direct structural information of confined CO2 in a micropore is important for elucidating its specific binding or activation mechanism. However, weak gas-binding ability and/or poor sample crystallinity after guest exchange hindered the development of efficient materials for CO2 incorporation, activation and conversion. Here, we present a dynamic porous coordination polymer (PCP) material with local flexibility, in which the propeller-like ligands rotate to permit CO2 trapping. This process can be characterized by X-ray structural analysis. Owing to its high affinity towards CO2 and the confinement effect, the PCP exhibits high catalytic activity, rapid transformation dynamics, even high size selectivity to different substrates. Together with an excellent stability with turnover numbers (TON) of up to 39,000 per Zn1.5 cluster of catalyst after 10 cycles for CO2 cycloaddition to form value-added cyclic carbonates, these results demonstrate that such distinctive structure is responsible for visual CO2 capture and size-selective conversion.

A novel cadmium-based metal-organic framework (MOF) material with dual-emission signals has been constructed that can act as the first example of MOF-implicated ratiometric sensor for mercury(II) in pure water with a fast response, high selectivity, and sensitivity. The sensing mechanism is also discussed.

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A heteroatom-rich 3D noninterpenetrating metal-organic framework (MOF) Cd-EDDA constructed from an ethylene glycol ether bridging tetracarboxylate ligand H4 EDDA (5,5'-(ethane-1,2-diylbis(oxy))diisophthalic acid) shows good chemical resistance to both acidic and alkaline solutions with a pH ranging from 2.0 to 12.2. There is a corresponding ratiometric luminescence response to pH from 2.0 to 11.5, and the sensing mechanism is also discussed through ion chromatography and molecular force field-based calculations. Importantly, the probe can easily be regenerated simply by modulating the pH of the solution, thus being the first example of a regenerable MOF-based ratiometric luminescent probe for pH.

A novel aldehyde-functionalized porous metal-organic framework (MOF) material has been constructed that can act as the first example of MOF-implicated sensors for discriminating Hcy from natural amino acids and even thiol-related peptides (GSH) with high sensitivity (LOD = 40 nM). The sensing mechanism is also discussed.

The scientific literature on blockchain technology is emerging but increasing rapidly. This review paper aims to provide a deeper understanding of the nature and scope of the extant literature on blockchain technology in the particular context of business organizations. To achieve our main objective, we searched five databases and screened 320 papers for inclusion. As a result of the search and screen process, we identified 39 relevant articles. Data coding was first pilot tested and then performed independently by two teams of researchers. All disagreements were reconciled by a third coder. Our findings reveal that most of the extant literature focuses on "how" blockchain technology works and, to a lesser extent, on the "what", i.e. its potential applications and usages in business organizations. For its part, the "why" question, which focuses on the organizational motivations for adopting blockchain technology, was scarcely discussed in prior literature. In short, our findings reveal that many issues and questions remain to be investigated. Based on a gap analysis, we propose a few promising avenues that shall guide future research efforts in this important topic.

The recovery of natural gas from CH4 hydrate deposits in permafrost environments through injection of CO2 is considered to be a suitable strategy for CH4 production and CO2 storage. To study the replacement characteristics of CO2–CH4 hydrate below the freezing point, the experiment was conducted in ice powder with particle size of 800 μm at different injection pressures (3.6, 4.0, and 4.5 MPa) of CO2. The experimental results showed that the average replacement rate and efficiency increased with the increasing of injected pressure of CO2 gas. Also, the average replacement rate and efficiency reached up to 0.403 mmol/h and 13.20% when the injected pressure of CO2 was at 4.5 MPa. The results also indicated that, compared with the temperature conditions above the freezing point, the replacement rate of CO2–CH4 hydrate was slow below the freezing point. These results provide a theoretical guidance for gas production from methane hydrate using CO2–CH4 replacement method in permafrost region in the future.

A simple and effective strategy was developed to immobilize ecofriendly dye inside a porous metal-organic framework (MOF) built from Eosin Y with [Cd(COO)(μ-HO)] secondary building units for the first time. The MOF exhibited efficient photocatalytic activity for H evolution under visible-light irradiation with a turnover number of 13920 and an initial turnover frequency of 7433 h, which was approximately 31 times the photocatalytic efficiency of Eosin Y.