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The production of ammonia (NH3) from nitrogen (N2) in mild electrochemical conditions is of prime importance to obtaining sustainable fertilizers and carbon-free energy conversion, which strongly depends on the electronic occupation state at reactive sites. Herein, the structural symmetry breaking is regulated to rearrange spin electron configuration in an effort to optimize the reaction pathway of nitrogen reduction. The structure distortion is achieved in multistage-coupled BiErRu2O7 pyrochlores by controlling the bonding interaction from Bi-6s lone pair electrons. The results demonstrate that the structural symmetry breaking can effectively optimize the bonding interaction and charge transfer between active sites and reactants, finally leading to the selection of reaction pathway from N2 to NH3. The structural symmetry breaking is regulated to rearrange spin electron configuration in multistage-coupled BiErRu2O7 pyrochlores, which can effectively optimize the bonding interaction and charge transfer between active sites and reactants, finally leading to the selection of reaction pathway from N2 to NH3. [ABSTRACT FROM AUTHOR]

The electrochemical conversion of CO 2 to HCOOH has been extensively regarded as a promising strategy to achieve carbon utilization. However, the direct synthesis of value-added HCOOH still encounters the difficulty of low energy conversion and selectivity. The performance of catalysts is determined by the electronic occupation at their half-filled 3d orbitals and their structural symmetry. Herein, we intentionally decorate some Co atoms onto Pd metallene to form a series of topological patterns to reveal their reaction kinetics, in an effort to achieve a higher catalytic activity. This work provides a new insight into boosting CO 2 electroreduction by designing topological patterns. • The electronic occupations at metal sites are optimized in their bonding interaction and charge transfer with adsorptive CO 2. • The morphology of Co active sites anchored onto Pd matrix directly affects the reaction kinetics of CO 2 electroreduction. • The electronic state coupling between Pd metallene and single Co atom boosts CO 2 electroreduction to HCOOH. [ABSTRACT FROM AUTHOR]

Bioconversion of CO2 into liquid fuels or chemicals, preferred medium chain carboxylic acids (caproic and caprylic acid), is an attractive CO2 utilization technology. The present study aims to investigate the effects of different ratios of H2/CO2 on regulating the distribution of C2‐C8 carboxylic acid products, while the headspace pressure of 1.5 bar was set to amplify the effect of different ratios. The H2/CO2 ratio of 4:1 was more suitable for preparing acetic acid, where the highest acetic acid yield was 17.5 g/L. And the H2/CO2 ratio of 2:1 showed excellent chain elongation ability with the highest n‐caprylic yield of 2.4 g/L. Additionally, the actual H2/CO2 ratios of 4:1 reactors were higher than that in 2:1 may be course chain elongation often accompanied by H2 production. The 16S rRNA genes analysis shows that the genus Terrisporobacter and Coriobacteriales may be related to acetic acid production enriched in H2/CO2 ratio 4:1 reactors, and the genus Clostridium and Paenibacillaceae may associate with the chain elongation pathway were enriched in H2/CO2 ratio 2:1 reactors. [ABSTRACT FROM AUTHOR]

Feline coronavirus (FCoV) is an unsegmented, single-stranded RNA virus belonging to the Alphacoronavirus genus. It can cause fatal feline infectious peritonitis (FIP) in cats of any ages. Currently, there are no effective prevention and control measures to against FCoV. In this study, we developed a recombinant adenovirus vaccine, AD5-N, based on the nucleocapsid(N) protein of FCoV. The immunogenicity of AD5-N was evaluated through intramuscular immunization in 6-week-old Balb/c mice and 9–12 months old cats. Compared to the control group, AD5-N specifically induced a significant increase in IgG and SIgA levels in the vaccinated mice. Furthermore, AD5-N not only effectively promoted strong cellular immune responses in cats but also induced high levels of specific SIgA, effectively helping cats resist FCoV infection. Our findings suggest that adenovirus vector vaccines based on the N gene have the potential to become candidate vaccines for the prevention and control of FCoV infection. • A recombinant adenovirus vaccine candidate named AD5-N for cats was developed. • AD5-N specifically induced a significant increase in IgG and SIgA levels in the vaccinated mice and cats. • AD5-N could provide effective protection for cats resisting type I FCoV and type II FCoV infection. [ABSTRACT FROM AUTHOR]

Waste-to-energy technologies for food waste (FW) and digestate treatment face environmental and economic barriers including pollutant emission and practical application concerns. This study investigated environmental impacts and economic feasibility of four scenarios to dispose 1 ton FW by life cycle assessment: Scenario A: mesophilic anaerobic digestion (AD) with digestate for biofertilizer; Scenario B: thermophilic AD with digestate for biofertilizer; Scenario C: mesophilic AD combining with digestate for 400 °C pyrolysis; and Scenario D: thermophilic AD combining with digestate for 700 °C pyrolysis. Scenario D was recommended for FW treatment especially for climate change, fine particulate matter formation, and Fossil depletion credits. Electrical recovery was identified as the most contributing and sensitive factor based on uncertainty and sensitivity analysis. Optimizing electrical generation efficiency from 39 % to 44 % benefited all 17 environmental categories through scenario analysis. Furthermore, Scenario D showed an economic advantage over the other scenarios, which was attributed to digestate post-treatment by 700 °C pyrolysis. This study provided a comprehensive reference for FW and digestate management. [Display omitted] • Anaerobic digestion coupled with pyrolysis is recommended for food waste treatment. • 700 °C pyrolysis as the post-treatment for AD digestate benefited climate change. • Biogas to electricity is a major contributor to environmental and economic benefits. • Enhancing electrical generation efficiency benefited all environmental categories. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effects of various microaerobic pretreatments on AD of tobacco straw were studied. • Biogas slurry as pretreatment agent dosing 4 mL/g VS of O 2 (BS-4) performed better. • BS-4 had a good performance in the lignocellulosic decomposition of tobacco straw. • O 2 dosing in microbial pretreatment process could change the microbial diversity. Tobacco straw is an abundant biomass in China's agricultural ecosystems, and has high potential for methane production. However, the anaerobic digestion (AD) efficiency is limited by the recalcitrant lignocellulose structure of the tobacco straw. In this study, three microaerobic pretreatments were performed for the AD of tobacco straw to increase methane production. Among them, microbial pretreatment with biogas slurry at an oxygen concentration of 4 mL/g VS resulted in the highest methane production of 349.1 mL/g VS, increasing by 19.8 % than that of untreated. During this pretreatment, the relative abundances of Enterococcus and Clostridium sensu stricto 12 , which are closely related to acetic acid production and cellulose degradation, were high, and these bacteria might have an important contribution to substrate hydrolysis and the methanogenesis efficiency of the AD process. This study advances the understanding of microaerobic pretreatment processes and provides technological guidance for the efficient utilization of tobacco straw. [ABSTRACT FROM AUTHOR]

[Display omitted] • The machine learning model for methane yield prediction was constructed. • Lignin content, organic loading and nitrogen content were vital predictive features. • The interaction of digestion time, cellulose and lignin contents was uncovered. • An online platform for methane yield prediction was created for public access. The biochemical methane potential test is a standard method to determine the biodegradability of lignocellulosic wastes (LWs) during anaerobic digestion (AD) with disadvantages of long experiment duration and high operating expense. This paper developed a machine learning model to predict the cumulative methane yield (CMY) using the data of 157 LWs regarding physicochemical characteristics, digestion condition and methane yield, with the coefficient of determination equal to 0.869. Model interpretability analyses underscored lignin content, organic loading, and nitrogen content as pivotal attributes for CMY prediction. For the feedstocks with a cellulose content exceeding about 50%, the CMY in the early AD stage would be relatively lower than those with low cellulose content, but prolonging digestion time could promote methane production. Besides, lignin content in feedstock surpassing 15% would significantly inhibit methane production. This work contributes to valuable guidance for feedstock selection and operation optimization for AD plants. [ABSTRACT FROM AUTHOR]