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The electrocatalytic hydrogenation (ECH) of furfural (FF) to furfuryl alcohol, which does not require additional hydrogen or high pressure, is a green and promising production route. In this study, we explore the effects of anions on FF ECH in two buffer electrolytes (KHCO3and phosphate-buffered saline [PBS]). Anions influence the yield of furfuryl alcohol through molecular activation and adsorption. Molecular dynamics simulations show that bicarbonate is present in the first shell layer of the FF molecule and induces strong hydrogen bonding interactions. In contrast, hydrogen phosphate is present only in the second shell layer, resulting in weak hydrogen bonding interactions. Owing to the interfacial anions and hydrogen bonding, FF molecules exhibit strong flat adsorption on the electrode surface in the KHCO3solution, while weak adsorption is observed in the PBS solution, as confirmed by operando synchrotron-radiation Fourier-transform infrared spectroscopy and in situ Raman spectroscopy. Density-functional theory calculations reveal that the overall anionic hydrogen bonding network promotes the activation of the carbonyl group in the FF molecule in KHCO3, whereas electrophilic activity is inhibited in PBS. Consequently, FF ECH demonstrates much faster kinetics in KHCO3, while it exhibits sluggish ECH kinetics and a severe hydrogen evolution reaction in PBS. This work introduces a new strategy to optimize the catalytic process through the modulation of the microenvironment.

Aqueous electrochemical coupling reactions, which enable the green synthesis of complex organic compounds, will be a crucial tool in synthetic chemistry. However, a lack of informed approaches for screening suitable catalysts is a major obstacle to its development. Here, we propose a pioneering electrochemical reductive coupling reaction toward direct electrosynthesis of oxime from NOxand aldehyde. Through integrating experimental and theoretical methods, we screen out the optimal catalyst, i.e., metal Fe catalyst, that facilitates the enrichment and C–N coupling of key reaction intermediates, all leading to high yields (e.g., ∼99% yield of benzaldoxime) for the direct electrosynthesis of oxime over Fe. With a divided flow reactor, we achieve a high benzaldoxime production of 22.8 g h–1gcat–1in ∼94% isolated yield. This work not only paves the way to the industrial mass production of oxime via electrosynthesis but also offers references for the catalyst selection of other electrochemical coupling reactions.

Electrochemical hydrogenation (ECH) of furfural, which uses the proton from water and avoids the usage of gaseous hydrogen and high pressure, is an efficient way to utilize biomass energy. Cu-based catalysts are promising catalysts for the ECH of furfural. However, their active sites and reaction mechanism have not been fully understood yet. This work unveils the active oxidation state of Cu-based electrocatalysts for the ECH of furfural. The co-existence of Cu+and Cu0on the CuO surface under the working potential is confirmed by a series of in situcharacterizations. The poisoning experiment shows that the performance decreased heavily after the Cu+was complexed with SCN−, indicating the decisive role of Cu+. Finally, the density functional theory (DFT) calculation suggests that the Cu0−Cu+synergistic effect is beneficial to both kinetics and thermodynamics: Cu+accelerates the second step hydrogenation process of furfural, and Cu0reduces the energy barrier for the desorption of furfuryl alcohol. This work demonstrates the synergistic effect of Cu0and Cu+states for the electrochemical hydrogenation of furfural and provides a deeper understanding of the furfural hydrogenation mechanism.

Combining the nitrogen reduction reaction (NRR) with organic molecule oxidation could reduce the overall energy consumption and improve resource utilization. In this issue of Chem Catalysis, the Shi group has designed a novel nitrogen-methanol co-electrolysis system by coupling the NRR with methanol reaction oxidation (MOR).

Hexamethylenetetramine (HMTA) is extensively used in the defense industry, medicines, food, plastics, rubber, and other applications. Traditional organic synthesis of HMTA relies on ammonia derived from the Haber process at high temperatures and pressures. In contrast, electrochemical methods enable a safe and green one-pot synthesis of HMTA from waste NO3–. However, HMTA synthesis through the electrochemical method is challenging owing to the complex reaction pathways involving C–N bond construction and ring formation. In this study, HMTA was efficiently synthesized over electrochemical oxidation-derived copper (e-OD-Cu), with a yield of 76.8% and a Faradaic efficiency of 74.9% at −0.30 VRHE. The catalytic mechanism and reaction pathway of HMTA synthesis on e-OD-Cu were investigated through a series of in situcharacterization methods and density-functional theory calculations. The results demonstrated that the electrocatalytic synthesis of HMTA involved a tandem electrochemical–chemical reaction. Additionally, the results indicated that the presence of Cu vacancies enhanced substrate adsorption and inhibited the further hydrogenation of C═N. Overall, this study provides an electrocatalytic method for HMTA synthesis and an electrochemical strategy for constructing multiple C–N bonds.

Apical membrane antigen-1 (AMA-1) has been described as a potential vaccine candidate in apicomplexan parasites. Here we characterize the ama-1 gene. The full-length ama-1 gene of Babesia sp. BQ1 (Lintan) (BLTAMA-1) is 1785 bp, which contains an open reading frame (ORF) encoding a 65-kDa protein of 594 amino acid residues; by definition, the 5′ UTR precedes the first methionine of the ORF. Phylogenetic analysis based on AMA-1 amino acid sequences clearly separated Piroplasmida from other Apicomplexa parasites. The Babesia sp. BQ1 (Lintan) AMA-1 sequence is most closely associated with that of B. ovata and B. bigemina, with high bootstrap value. A recombinant protein encoding a conserved region and containing ectodomains I and II of BLTAMA-1 was constructed. BLTrAMA-1-DI/DII proteins were tested for reactivity with sera from sheep infected by Babesia sp. BQ1 (Lintan). In Western-blot analysis, native Babesia sp. BQ1 (Lintan) AMA-1 proteins were recognized by antibodies raised in rabbits against BLTrAMA-1 in vitro. The results of this study are discussed in terms of gene characterization, taxonomy and antigenicity. [ABSTRACT FROM AUTHOR]

A clear understanding of the main controlling factors for injection and production allocation of polymer flooding is the key to successful differential adjustment for well management in high water cut reservoirs. Generally, sensitivity analysis or design of experiment is used to study the main controlling factors, but the number of adjustment parameters is limited and the optimal results are hard to obtain. Therefore, the paper regards the problem as an inverse problem and studies the controlling factors by combining intelligent optimization and correlation analysis. In general, the correlation between the optimal results of injection and production allocation and each controlling factor is analyzed, and the main controlling factors with the strongest correlation are selected. Results show that injection rate allocation is mainly controlled by pore volume, polymer concentration allocation is mainly controlled by pore volume and formation coefficient, and production rate allocation is mainly controlled by remaining reserves and oil saturation. The case study indicates injection and production adjustment based on the main controlling factors obtains satisfactory development performance while using much less computation cost than that of the intelligent optimization method. The research results provide a good reference for well redistribution adjustment of polymer flooding in large-scale oilfields.

Ovine babesiosis is one of the most important tick-borne haemoparasitic diseases of small ruminants. The ovine parasite Babesia sp. Xinjiang is widespread in China. In this study, recombinant full-length XJrRAP-1aα2 (rhoptry-associated protein 1aα2) and C-terminal XJrRAP-1aα2 CT of Babesia sp. Xinjiang were expressed and used to evaluate their diagnostic potential for Babesia sp. Xinjiang infections by indirect enzyme-linked immunosorbent assay (ELISA). Purified XJrRAP-1aα2 was tested for reactivity with sera from animals experimentally infected with Babesia sp. Xinjiang and other haemoparasites using Western blotting and ELISA. The results showed no cross-reactivities between XJrRAP-1aα2 CT and sera from animals infected by other pathogens. High level of antibodies against RAP-1a usually lasted 10 weeks post-infection (wpi). A total of 3690 serum samples from small ruminants in 23 provinces located in 59 different regions of China were tested by ELISA. The results indicated that the average positive rate was 30·43%, and the infections were found in all of the investigated provinces. This is the first report on the expression and potential use of a recombinant XJrRAP-1aα2 CT antigen for the development of serological assays for the diagnosis of ovine babesiosis, caused by Babesia sp. Xinjiang. [ABSTRACT FROM AUTHOR]

Stimuli‐sensitive polymer materials have limited device functionality, design and manufacturing flexibility although they are pushed to enable smart device applications. Here we demonstrate the capability of integrating thermoresponsive poly(N‐isopropylacrylamide) (PNIPAAm) hydrogels with silicon nanoribbons, and enable the stiff silicon ribbons to become adaptive and drivable by the soft environmentally sensitive substrate, such as becoming mechanically stretched and compressed on temperature change. These and related soft/hard smart devices and systems may open new opportunities in biomedical applications.