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The electrochemical process of coupling electrocatalytic CO2 reduction and organic conversion reaction can effectively reduce the reaction overpotential and obtain value-added chemicals. Moreover, because of the diversity of substrates and the designability of coupling forms, more and more attention has been paid to this field. This review systematically summarizes the research progress of coupling electrolysis in recent years, (1) co-electrolysis of CO2 and organics at the cathode to obtain specific products with high selectivity, (2) replacing traditional anodic oxygen evolution reaction (OER) with other valuable oxidation reactions to improve energy utilization efficiency and economic benefits of CO2 conversion, (3) in an electrolytic cell without membrane, the cathode and anode jointly transform CO2 and organics to redox products. We hope that the examples and insights on coupling electrolysis introduced in this review can inspire researchers to further explore and innovate in this direction.
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BACKGROUND: Durvalumab plus gemcitabine and cisplatin has a significant clinical benefit for advanced biliary tract cancer (BTC). However, the high price of durvalumab warrants an exploration of the economics. OBJECTIVE: To investigate the cost-effectiveness of adding durvalumab to gemcitabine and cisplatin compared with gemcitabine and cisplatin in first-line therapy of advanced BTC from the perspective of the Chinese healthcare system. METHODS: According to the TOPAZ-1 trial, a three-state Markov model was built by the TreeAge Pro 2022 software. The total costs and quality-adjusted life years (QALYs) were estimated, and the incremental cost-effectiveness ratio (ICER) was used as the evaluation index. The triple 2021 Chinese per capita gross domestic product (GDP) of $37,663.26/QALY was used as the willingness-to-pay (WTP) threshold. Outputs were analyzed for two scenarios with and without a durvalumab drug charity assistance policy. In the scenario analysis, the base-case model was run multiple times with different prices of durvalumab to determine the effect on the ICER. Moreover, the robustness of the model was tested through sensitivity analyses. RESULTS: Compared with chemotherapy alone, durvalumab plus chemotherapy resulted in an additional 0.12 QALY and an incremental cost of $18,555.19, the ICER was $159,644.70/QALY under the situation of charity assistance, and the ICER was $696,571.11/QALY without charity assistance, both exceeding the WTP threshold in China. The scenario analysis demonstrated that when the price of durvalumab fell by more than 94.2% to less than $0.33/mg, durvalumab plus chemotherapy will be more economical compared with chemotherapy alone under the situation of no charity assistance. One-way sensitivity analyses suggested that the cost of durvalumab had the greatest influence on the ICERs, and the probabilistic sensitivity analyses demonstrated that durvalumab plus chemotherapy was impossible to be cost-effective at the WTP threshold whether the charity assistance was available or not. CONCLUSIONS: Adding durvalumab to gemcitabine and cisplatin was not cost-effective for advanced BTC regardless of receiving and not receiving charitable assistance.
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Photo-driven CH4 conversion to multi-carbon products and H2 is attractive but challenging, and the development of efficient catalytic systems is critical. Herein, we construct a solar-energy-driven redox cycle for combining CH4 conversion and H2 production using iron ions. A photo-driven iron-induced reaction system was developed, which is efficient at selective coupling of CH4 as well as conversion of benzene and cyclohexane under mild conditions. For CH4 conversion, 94 % C2 selectivity and a C2 H6 formation rate of 8.4â µmol h-1 is achieved. Mechanistic studies reveal that CH4 coupling is induced by hydroxyl radical, which is generated by photo-driven intermolecular charge migration of an Fe3+ complex. The delicate coordination structure of the [Fe(H2 O)5 OH]2+ complex ensures selective C-H bond activation and C-C coupling of CH4 . The produced Fe2+ can be used to reduce the potential for electrolytic H2 production, and then turns back into Fe3+ , forming an energy-saving and sustainable recyclable system.
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Ferro , Metano , Ferro/química , Metano/química , Etano/química , Oxirredução , Radical HidroxilaRESUMO
Photocatalytic reduction of CO2 into energy-rich carbon compounds has attracted increasing attention. However, it is still a challenge to selectively and effectively convert CO2 to a desirable reaction product. Herein, we report a design of a synergistic photocatalyst for selective reduction of CO2 to CO by using a covalent organic framework bearing single Ni sites (Ni-TpBpy), in which electrons transfer from photosensitizer to Ni sites for CO production by the activated CO2 reduction under visible-light irradiation. Ni-TpBpy exhibits an excellent activity, giving a 4057 µmol g-1 of CO in a 5 h reaction with a 96% selectivity over H2 evolution. More importantly, when the CO2 partial pressure was reduced to 0.1 atm, 76% selectivity for CO production is still obtained. Theoretical calculations and experimental results suggest that the promising catalytic activity and selectivity are ascribed to synergistic effects of single Ni catalytic sites and TpBpy, in which the TpBpy not only serves as a host for CO2 molecules and Ni catalytic sites but also facilitates the activation of CO2 and inhibits the competitive H2 evolution.
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Yolk-shell nanoreactors have received considerable interest for use in catalysis. However, the controlled synthesis of continuous crystalline shells without imperfections or cracks remains challenging. Here, a strategy for the synthesis of yolk-shell metal nanoparticles@covalent organic framework (MNPs@COF) nanoreactors by using MNPs@ZIF-8 core-shell nanostructures as a self-template is designed and developed. The COF shell is formed through an amorphous-to-crystalline transformation process of a polyimine shell in a mildly acidic solution, while the ZIF-8 is etched in situ, generating a void space between the MNPs core and the COF shell. With the protection of the COF shell, multiple ligand-free MNPs are confined inside of the hollow nanocages. Importantly, the synthetic strategy can be generalized to engineer the functions and properties of the designed yolk-shell nanocages by varying the structure of the COF shell and/or the composition of the core MNPs. Representative Pd@H-TpPa yolk-shell nanocages with active Pd NP cores and permeable TpPa shells exhibit high catalytic activity and stability in the reduction of 4-nitrophenol by NaBH4 at room temperature.
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Photocatalytic coupling of methane to ethane and ethylene (C2 compounds) offers a promising approach to utilizing the abundant methane resource. However, the state-of-the-art photocatalysts usually suffer from very limited C2 formation rates. Here, we report our discovery that the anatase TiO2 nanocrystals mainly exposing {101} facets, which are generally considered less active in photocatalysis, demonstrate surprisingly better performances than those exposing the high-energy {001} facet. The palladium co-catalyst plays a pivotal role and the Pd2+ site on co-catalyst accounts for the selective C2 formation. We unveil that the anatase {101} facet favors the formation of hydroxyl radicals in aqueous phase near the surface, where they activate methane molecules into methyl radicals, and the Pd2+ site participates in facilitating the adsorption and coupling of methyl radicals. This work provides a strategy to design efficient nanocatalysts for selective photocatalytic methane coupling by reaction-space separation to optimize heterogeneous-homogeneous reactions at solid-liquid interfaces.
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Fast skeletal troponin C (TNNC2) plays a key role in the regulation of muscle contraction, and modulates the Ca2+-activation characteristics of muscle fibers. In this study, we characterized the full-length cDNA of the porcine TNNC2 gene, which is composed of a 65 bp 5'UTR, a 483 bp (ORF) and a 174 bp 3' UTR. Northern blot analysis indicated that the TNNC2 gene had one transcript of approximately 0.7 kb and was expressed exclusively in skeletal muscle (triceps brachii, biceps femoris and longissimus dorsi). SDS-PAGE and Western blotting analysis indicated that the porcine TNNC2 protein comprised 160 amino acids, and had a molecular mass of 18 kDa. The porcine TNNC2 gene, which spans 3.2 kb, was isolated and was found to be composed of six exons. All exon/intron boundaries adhered to the GT/AG rule. Altogether 20 nucleotide polymorphisms of the TNNC2 gene were discovered in Duroc, Landrace, Lantang and Dahuabai pigs, and included three missense mutations and 17 intronic substitutions. Five of the polymorphisms were genotyped in Lantang, Dahuabai, Landrace, Large White and Duroc pigs using PCR-RFLP. Significant differences in genotype frequencies were observed between the Chinese native breeds (Lantang and Dahuabai) and the western breeds (Landrace, Large White and Duroc). These datas have identified the TNNC2 gene as an excellent model system for studies of developmentally regulated gene expression and a novel marker suitable for studies of the association of candidate genes with growth traits in porcine skeletal muscle.
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Componentes do Gene , Polimorfismo Genético , Troponina C/genética , Regiões 3' não Traduzidas , Regiões 5' não Traduzidas , Animais , DNA Complementar , Perfilação da Expressão Gênica , Frequência do Gene , Genótipo , Músculo Esquelético , RNA Mensageiro , Especificidade da Espécie , Sus scrofaRESUMO
A fluorescent covalent organic framework (COF), featuring precise distribution of thioether pendant arms inside the cavity, was designed. The thioether-functionalized COF exhibits selective sensing and capture of Au ions at ultra-trace levels in water with high sensitivity, selectivity and adsorption capacity, which makes it an excellent candidate for selective detection and recovery of Au.