Potential Large-Scale CO2 Utilisation for Salicylic Acid Production via a Suspension-Based Kolbe-Schmitt Reaction in Toluene.

Conversion of CO2 into organic chemicals offers a promising route for advancing the circularity of carbon capture, utilisation, and storage in line with the international 2050 Net Zero agenda. The widely known commercialised chemical fixation of CO2 into organic chemicals is the century-old Kolbe-Schmitt reaction, which carboxylates phenol (via sodium phenoxide) into salicylic acid. The carboxylation reaction is normally carried out between the gas-solid phases in a batch reactor. The mass and heat transfer limitations of such systems require rather long reaction times and a high pressure of CO2 and are often characterised by the low formation of undesirable side products. To address these drawbacks, a novel suspension-based carboxylation method has been designed and carried out in this present study, where sodium phenoxide is dispersed in toluene to react with CO2. Importantly, the addition of phenol played a critical role in promoting the stoichiometric conversion of phenoxide to salicylic acid. Under the optimal conditions of a phenol/phenoxide molar ratio of 2:1 in toluene, a reaction temperature of 225 °C, a CO2 pressure of 30 bar, a reaction time of 2 h, and stirring at 1000 rpm, an impressive salicylic acid molar yield of 92.68% has been achieved. The reaction mechanism behind this has been discussed. This development provides us with the potential to achieve a carboxylation reaction of phenoxide with CO2 more effectively in a continuous reactor. It can also facilitate the large-scale fixing of CO2 into hydroxy aromatic carboxylic acids, which can be used as green organic chemical feedstocks for making various products, including long-lived polymeric materials.

UV Light-Driven Nitric Oxide Release from Porous Nitrogen Heterocyclic Polymers.

In this study, porous polymers with nitrogen heterocyclic core structures are synthesized through the condensation of enaminonitrile and terephthalaldehyde monomers. These polymers are used as a platform to store bioactive nitric oxide (NO) and control its release. NO loading is achieved by nitrosating the polymers with acidified nitrite, a process that also imparts photoresponsivity to the polymers. Polymer composition and porosity affect NO storage and release. It is observed that under UV light at 365 nm in a PBS solution, the polymers (NO@DHP-POP) can release NO in a manner fully controlled by UV lighting. Under experimental conditions, these porous polymers release NO at a rate of ≈10.0-50.0 µmol g-1 over 60 min. These findings demonstrate the potential of these polymers for integrating NO delivery into phototherapy applications.

Ultraviolet Light Responsive N-Nitroso Polymers for Antibacterial Nitric Oxide Delivery.

This study investigates the incorporation of active secondary amine moieties into the polymer backbone by co-polymerizing 2,4,6-tris(chloromethyl)-mesitylene with three diamines, namely 1,4-diaminobutane, m-phenylenediamine, and p-phenylenediamine. This process results in the stabilization of the amine moieties and the subsequently introduced nitroso groups. Charging bioactive nitric oxide (NO) into the polymers is accomplished by converting the amine moieties into N-nitroso groups. The ability of the polymers to store and release NO depends on their structures, particularly the amount of incorporated active secondary amines. With grafting photosensitive N-nitroso groups into the polymers, the derived NO@polymers exhibit photoresponsivity. NO release is completely regulated by adjusting UV light irradiation. These resulting polymeric NO donors demonstrate remarkable bactericidal and bacteriostatic activity, effectively eradicating E. coli bacteria and inhibiting their growth. The findings from this study hold promising implications for combining NO delivery with phototherapy in various medical applications.

Effects of Carbon Tax on Urban Carbon Emission Reduction: Evidence in China Environmental Governance.

Carbon tax is an important economic instrument in achieving the goal of carbon emission reduction and sustainable development. This paper investigates the effects of carbon tax on carbon emission reduction in China. First, a non-competitive input-output table for Carbon Emissions of 28 sectors in China after Carbon Tax was established, based on the "2018 China Non-competitive Input-Output Table (42 Sectors)" and the carbon emission data of sectors provided by China Carbon Emission Accounts and Datasets (CEADs). Then, an input-output price model was established to study the changes on product price, GDP, employment, and carbon dioxide emissions of 28 sectors after carbon taxing ranged from 10 to 200. When the carbon tax rate reaches 200 yuan/ton, the inflation rate will be 5.907%, the total GDP will be decreased to 1.910%, the total labor force will be decreased to 1.744%, and the total carbon emission reduction rate will be increased to 8.171%. Results showed that with the increases in carbon tax, the inflation rate was increased, the rate of carbon emission reduction was increased, and the negative effects on GDP and employment were also increased. Suggestions on policy making, such as combination of carbon taxing and carbon trading, dynamic adjustment mechanism, tax neutrality, and forcing active carbon reduction, were proposed to minimize the adverse effect of levying carbon tax. The results from this paper would provide a reference for the policy making on carbon management.

FeIII in the high-spin state in dimethylammonium bis[3-ethoxysalicylaldehyde thiosemicarbazonato(2-)-κ3O2,N1,S]ferrate(III).

The synthesis and crystal structure (100 K) of the title compound, [(CH3)2NH2][Fe(C10H11O2N3S)2], are reported. The asymmetric unit consists of an octahedral [FeIII(L)2]- fragment, where L2- is 3-ethoxysalicylaldehyde thiosemicarbazonate(2-), and a dimethylammonium cation. Each L2- ligand binds with the thiolate S, the imine N and the phenolate O atoms as donors, resulting in an FeIIIS2N2O2 chromophore. The ligands are orientated in two perpendicular planes, with the O and S atoms in cis positions, and mutually trans N atoms. The FeIII ion is in the high-spin state at 100 K. The variable-temperature magnetic susceptibility measurements (5-320 K) are consistent with the presence of a high-spin FeIII ion with D = 0.83 (1) cm-1 and g = 2.

Critical role of chemical potential to assure effective encapsulation.

HYPOTHESIS: In emulsification-polymerisation avoiding monomer escape from emulsion droplets is the key to successful encapsulation. So far, it is believed that (1) a hydrophobe needs to be included and (2) free-micelles of surfactant need to be depleted. However, these criteria do not always work. The paper explores the critical role of the chemical potential difference between the inside and outside of the emulsion droplet for successful encapsulation. EXPERIMENTS: Crossflow membrane emulsification was used to produce uniform droplets of 1-2 µm of solutions of 3-iodoprop-2-yn-1-yl butylcarbamate (a biocide), castor oil (hydrophobe) in methyl 2-methylprop-2-enoate (monomer) into aqueous solutions with a large amount of free-micelles of surfactant. The encapsulation was followed by polymerisation. The size distribution of microcapsule from different formula were examined. FINDINGS: The biocide encapsulation depends on castor oil content: >12% (full); 6-12% (either full or partial); <6% (minor). Results show a critical molar fraction ratio of the monomer in the droplet to water in the aqueous phase that provides a definitive criterion to assure size retention and full encapsulation. This critical value corresponds to an energy barrier of 116 J/mol to prevent the monomer escaping. This finding is proposed to be used as an advanced rule to guide precision formulation for desired microencapsulation.

Feasibility of Solar Updraft Towers as Photocatalytic Reactors for Removal of Atmospheric Methane-The Role of Catalysts and Rate Limiting Steps.

Due to the alarming speed of global warming, greenhouse gas removal from atmosphere will be absolutely necessary in the coming decades. Methane is the second most harmful greenhouse gas in the atmosphere. There is an emerging technology proposed to incorporating photocatalysis with solar updraft Towers (SUT) to remove methane from the air at a planetary scale. In this study, we present a deep analysis by calculating the potential of methane removal in relation to the dimensions and configuration of SUT using different photocatalysts. The analysis shows that the methane removal rate increases with the SUT dimensions and can be enhanced by changing the configuration design. More importantly, the low methane removal rate on conventional TiO2 photocatalyst can be significantly improved to, for example, 42.5% on a more effective Ag-doped ZnO photocatalyst in a 200 MW SUT while the photocatalytic reaction is the rate limiting step. The factors that may further affect the removal of methane, such as more efficient photocatalysts, night operation and reaction zone are discussed as possible solutions to further improve the system.

Power Generation Performance of a Pilot-Scale Reverse Electrodialysis Using Monovalent Selective Ion-Exchange Membranes.

Reverse electrodialysis (RED) is a promising process for harvesting energy from the salinity gradient between two solutions without environmental impacts. Seawater (SW) and river water (RW) are considered the main RED feed solutions because of their good availability. In Okinawa Island (Japan), SW desalination via the reverse osmosis (RO) can be integrated with the RED process due to the production of a large amount of RO brine (concentrated SW, containing ~1 mol/dm3 of NaCl), which is usually discharged directly into the sea. In this study, a pilot-scale RED stack, with 299 cell pairs and 179.4 m2 of effective membrane area, was installed in the SW desalination plant. For the first time, asymmetric monovalent selective membranes with monovalent selective layer just at the side of the membranes were used as the ion exchange membranes (IEMs) inside the RED stack. Natural and model RO brines, as well as SW, were used as the high-concentrate feed solutions. RW, which was in fact surface water in this study and close to the desalination plant, was utilized as the low-concentrate feed solution. The power generation performance investigated by the current-voltage (I-V) test showed the maximum gross power density of 0.96 and 1.46 W/m2 respectively, when the natural and model RO brine/RW were used. These are a 50-60% improvement of the maximum gross power of 0.62 and 0.97 W/m2 generated from the natural and model SW, respectively. The approximate 50% more power generated from the model feed solutions can be assigned to the suppression of concentration polarization of the RED stack due to the absence of multivalent ions.

IL-6, IL-10 and IL-13 are associated with pathogenesis in children with Enterovirus 71 infection.

In the present study, the aim was to reveal the relationship of serum IL-6, IL-10 and IL-13 levels in patient with Enterovirus 71 (EV71) infection. To elucidate the role of immune mechanisms in the pathogenesis of Hand, foot, and mouth disease (HFMD), we analyzed the cytokine of 112 EV71-infected patients. A significant elevation of serum (interleukin) IL-6, IL-10 and IL-13 levels in patients with EV71 infection compare with Un-EV71 infection HFMD patient and Healthy individuals. The production of inflammatory cytokines was increased with disease clinical stage. In addition, the immunological consequences of these cytokine in patient with EV71 infection showed a downward trend after cure. These data suggested that EV71 infection significantly increased the release of circulating IL-6, IL-10 and IL-13. The systemic inflammatory response may play an important role in the pathogenesis of HFMD. Moreover, this study may be designed to evaluate the potential therapeutic of medicine in the treatment of patients with EV71 infection.

Exceptional function of nanoporous metal organic framework particles in emulsion stabilisation.

A new concept of nanoporous metal organic framework particles stabilising emulsions was investigated. The copper benzenetricarboxylate MOF particles adsorbed at the oil/water interface play an exceptional role in stabilising both oil-in-water and water-in-oil emulsions.

Responsive core-shell latex particles as colloidosome microcapsule membranes.

Responsive core-shell latex particles are used to prepare colloidosome microcapsules using thermal annealing and internal cross linking of the shell, allowing the production of the microcapsules at high concentrations. The core-shell particles are composed of a polystyrene core and a shell of poly[2-(dimethylamino)ethyl methacrylate]-b-poly[methyl methacrylate] (PDMA-b-PMMA) chains adsorbed onto the core surface, providing steric stabilization. The PDMA component of the adsorbed polymer shell confers thermally responsive and pH-responsive characteristics to the latex particle, and it also provides glass transitions at temperatures lower than those of the core and reactive amine groups. These features facilitate the formation of stable Pickering emulsion droplets and the immobilization of the latex particle monolayer on these droplets to form colloidosome microcapsules. The immobilization is achieved through thermal annealing or cross linking of the shell under mild conditions feasible for large-scale economic production. We demonstrate here that it is possible to anneal the particle monolayer on the emulsion drop surface at 75-86 °C by using the lower glass-transition temperature of the shell compared to that of the polystyrene cores (∼108 °C). The colloidosome microcapsules that are formed have a rigid membrane basically composed of a densely packed monolayer of particles. Chemical cross linking has also been successfully achieved by confining a cross linker within the disperse droplet. This approach leads to the formation of single-layered stimulus-responsive soft colloidosome membranes and provides the advantage of working at very high emulsion concentrations because interdroplet cross linking is thus avoided. The porosity and mechanical strength of the microcapsules are also discussed here in terms of the observed structure of the latex particle monolayers forming the capsule membrane.