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The thermal effect of coal pyrolysis is a key parameter in the process of coal pyrolysis mechanism research and reactor design. At present, there are a lot of differences in the accuracy of evaluation methods for coal pyrolysis thermal effect. The most widely used and feasible method is based on simultaneous thermal analyzer (TG-DSC synchronous combination). However, this method still relies heavily on the measurement accuracy of the instrument, and there are also some differences in the accuracy of thermal effect calculation methods after the heat flow curve is obtained, resulting in a poor repeatability of the data and difficulty in adapting to the needs of large-scale production and process design. Tar-rich coal is high-quality raw material for coal to tar, it contains more hydrogen-rich structures such as aliphatic side chains and bridge bonds, it could be pyrolyzed to produce more tar during pyrolysis. The regulation of pyrolysis process is the key factor affecting the quality of tar produced by the pyrolysis of tar-rich coal, and the thermal effect of pyrolysis process is an important parameter for selecting pyrolysis process. Therefore, it is urgent to develop an accurate and efficient evaluation method of coal pyrolysis thermal effect for both tar-rich coal pyrolysis and generalized coal conversion. Based on the experimental results for the slow pyrolysis of tar-rich coal, combined with pyrolysis reaction mechanism and empirical formula, the product-oriented pyrolysis reaction system of tar-rich coal was constructed. The chemical reaction heat for the pyrolysis process of tar-rich coal was obtained by the thermodynamic calculation of the reaction system using the classical thermodynamic analysis method. Combined with the physical heat absorption in the pyrolysis process, the thermal effect in the low-temperature slow pyrolysis process of tar-rich coal could be obtained. Then, based on the reported coal pyrolysis experimental results and measured values of pyrolysis thermal effect, the random forest model of machine learning method was used to nonlinearly model and predict the thermal effect of coal pyrolysis. The results showed that based on experimental results, the thermal effect value for slow pyrolysis of tar-rich coal calculated by the product-oriented calculation was generally lower than that measured by TG-DSC synchronous combination, and the error was within 10%. The prediction accuracy for the thermal effect value of tar-rich coal pyrolysis based on machine learning algorithm was 0.935 2. Overall, the two prediction models of thermal effect of tar-rich coal pyrolysis constructed were practical and applicable.

Abstract To solve the problems of low gasification efficiency and high tar content caused by solid–solid contact between biomass and oxygen carrier in traditional biomass chemical looping gasification process. The decoupling strategy was adopted to decouple the biomass gasification process, and the composite oxygen carrier was prepared by embedding Fe2O3 in molecular sieve SBA-16 for the chemical looping reforming process of pyrolysis micromolecular model compound methane, which was expected to realize the directional reforming of pyrolysis volatiles to prepare hydrogen-rich syngas. Thermodynamic analysis of the reaction system was carried out based on the Gibbs free energy minimization method, and the reforming performance was evaluated by a fixed bed reactor, and the kinetic parameters were solved based on the gas–solid reaction model. Thermodynamic analysis verified the feasibility of the reaction and provided theoretical guidance for experimental design. The experimental results showed that the reaction performance of Fe2O3@SBA-16 was compared with that of pure Fe2O3 and Fe2O3@SBA-15, and the syngas yield was increased by 55.3% and 20.7% respectively, and it had good cycle stability. Kinetic analysis showed that the kinetic model changed from three-dimensional diffusion to first-order reaction with the increase of temperature. The activation energy was 192.79 kJ/mol by fitting. This paper provides basic data for the directional preparation of hydrogen-rich syngas from biomass and the design of oxygen carriers for pyrolysis of all-component chemical looping reforming.

The biomass chemical looping gasification process involves various complex reaction processes, including pyrolysis, gasification, and reforming, which occur within the same reaction space. These reactions exhibit intricate interactions, posing challenges for achieving targeted control. Consequently, some issues arise, such as low carbon conversion, high tar yield, and difficulties in attaining auto thermal operation. The biomass pyrolysis chemical looping re-forming process, employing the decoupling strategy, aims to achieve an independent regulation of pyrolysis and reforming reactions, thereby mitigating the issues mentioned above. The process underwent simulation using the Aspen Plus software, and the model’s validity was confirmed by comparing it with the results of pyrolysis experiments. Using the established process model, the impact of pyrolysis reactor temperature, fuel reactor temperature, and steam-to-biomass mass ratio on process performance was examined. The results demonstrate the effective predictive capability of the established process model regarding the distribution of pyrolysis products within the temperature range of 400−600 ℃. As the pyrolysis temperature rises, the syngas yield exhibits a generally increasing trend, reaching its peak at 550 ℃ with a value of 1158.98 Nm3/kg biomass. At a pyrolysis temperature of 600 ℃, the heat demand of the reforming reactor is adequately met by the exothermic reactions of pyrolysis char and oxygen carrier oxidation without any surplus energy. Elevating the fuel reactor temperature augments the syngas yield but diminishes the H2-to-CO ratio and energy efficiency of the syngas while also necessitating a substantial increase in the circulation rate of bed material for achieving auto thermal operation. Steam serves as an effective regulator for controlling the H2-to-CO ratio in syngas. The pyrolysis chemical looping reforming process generates syngas with an H2-to-CO ratio of 2.0 when the steam-to-biomass mass ratio is 0.45, lower than the ratio needed for the biomass chemical looping gasification process. Consequently, taking into account the syngas yield and process performance, the recommended operating conditions for the pyrolysis chemical looping reforming process are as follows: a pyrolysis reactor temperature ranging from 550 to 600 ℃, a fuel reactor temperature of 700 ℃, and a steam-to-biomass mass ratio of 0.45.

Abstract Improving the resistance of Saccharomyces cerevisiae to vanillin, derived from lignin, will benefit the design of robust cell factories for lignocellulosic biorefining. The transcription factor Yrr1p mediates S. cerevisiae resistance to various compounds. In this study, eleven predicted phosphorylation sites were mutated, among which 4 mutants of Yrr1p, Y134A/E and T185A/E could improve vanillin resistance. Both dephosphorylated and phosphorylated mutations at Yrr1p 134 and 185 gathered in the nucleus regardless of the presence or absence of vanillin. However, the phosphorylated mutant Yrr1p inhibited target gene expression, while dephosphorylated mutants promoted expression. Transcriptomic analysis showed that the dephosphorylated Yrr1p T185 mutant, under vanillin stress, upregulated ribosome biogenesis and rRNA processing. These results demonstrate the mechanism by which Yrr1p phosphorylation regulates the expression of target genes. The identification of key phosphorylation sites in Yrr1p offers novel targets for the rational construction of Yrr1p mutants to improve resistance to other compounds.

Chemical looping gasification (CLG) characteristics and kinetic analysis of Chlorella (CHL), simulated Chlorella (V-CHL) and medium-chain triglycerides (MCT) were investigated using a thermogravimetric analyzer coupled with an online mass spectrometer. The apparent activation energy was obtained via Kissinger-Akahira-Sunose (KAS) method. In the result of the weightless behavior, the addition of oxygen carrier inhibited the decomposition of V-CHL at lower temperatures but promoted its decomposition at high temperatures. The values of chemical looping process characteristic parameters showed that a 10 wt% oxygen carrier would maximize the release of volatile products in the CLG of MCT, with 5.12 × 10−6 %·min−1·oC−3. Oxygen carriers also affected gaseous products. The LHV of gaseous products of CHL reached the largest when the oxygen carrier was 10 wt%, which was 8.13 MJ/m3. And the gaseous product of MCT had the largest LHV with 30 wt% oxygen carrier, which was 8.83 MJ/m3. According to the kinetic analysis, the minimum value of apparent activation energy of MCT chemical looping gasification was 89.54 kJ·mol−1 with the oxygen carrier of 30 wt%, which was 50% less than that of MCT pyrolysis. And the minimum value for V-CHL was obtained when the mass fraction of Fe2O3 was 50 wt%. This paper could provide a reference for the choice of algae, the design of reactors, and the targeted regulation of the gaseous product for the algae CLG process.

Autophagy is a highly conserved intracellular degradation pathway in eukaryotic organisms, playing an adaptive role in various pathophysiological processes throughout evolution. Inflammation is the immune system’s response to external stimuli and tissue damage. However, persistent inflammatory reactions can lead to a range of inflammatory diseases and cancers. The interaction between autophagy and inflammation is particularly evident during viral infections. As a crucial regulator of inflammation, autophagy can either promote or inhibit the occurrence of inflammatory responses. In turn, inflammation can establish negative feedback loops by modulating autophagy to suppress excessive inflammatory reactions. This interaction is pivotal in the pathogenesis of viral diseases. Therefore, elucidating the regulatory roles of autophagy and inflammation in viral infections will significantly enhance our understanding of the mechanisms underlying related diseases. Furthermore, it will provide new insights and theoretical foundations for disease prevention, treatment, and drug development.

Studying the mechanisms of resistance to vanillin in microorganisms, which is derived from lignin and blocks a major pathway of DNA double-strand break repair in yeast, will benefit the design of robust cell factories that produce biofuels and chemicals using lignocellulosic materials. A high vanillin-tolerant Saccharomyces cerevisiae strain EMV-8 carrying site mutations compared to its parent strain NAN-27 was selected for the analyses. The dynamics of the chromatin structure of eukaryotic cells play a critical role in transcription and the regulation of gene expression and thus the phenotype. Consequently, Hi-C and transcriptome analyses were conducted in EMV-8 and NAN-27 in the log phase with or without vanillin stress to determine the effects of mutations and vanillin disturbance on the dynamics of three-dimensional chromosome organization and the influence of the organization on the transcriptome. The outcomes indicated that the chromosome interaction pattern disturbed by vanillin stress or genetic mutations in the log phase was similar to that in mouse cells. The short chromosomes contact the short chromosomes, and the long chromosomes contact the long chromosomes. In response to vanillin stress, the boundaries of the topologically associating domain (TAD) in the vanillin-tolerant strain EMV-8 were more stable than those in its parent strain NAN-27. The motifs of SFL1, STB3, and NHP6A/B were enriched at TAD boundaries in both EMV-8 and NAN-27 with or without vanillin, indicating that these four genes were probably related to TAD formation. The Indel mutation of YRR1, whose absence was confirmed to benefit vanillin tolerance in EMV-8, caused two new interaction sites that contained three genes, WTM2, PUP1, and ALE1, whose overexpression did not affect vanillin resistance in yeast. Overall, our results revealed that in the log phase, genetic mutations and vanillin disturbance have a negligible effect on three-dimensional chromosome organization, and the reformation or disappearance of TAD boundaries did not show an association with gene expression, which provides an example for studying yeast chromatin structure during stress tolerance using Hi-C technology.

Abstract Background Vanillin is one of the important phenolic inhibitors in Saccharomyces cerevisiae for bioconversion of lignocellulosic materials and has been reported to inhibit the translation process in cells. In our previous studies, it was confirmed that the deletion of the transcription factor gene YRR1 enhanced vanillin resistance by promoting some translation-related processes at the transcription level. In this work, we investigated the effects of proteomic changes upon induction of vanillin stress and deletion of YRR1 to provide unique perspectives from a transcriptome analysis for comprehending the mechanisms of YRR1 deletion in the protective response of yeast to vanillin. Results In wild-type cells, vanillin reduced two dozens of ribosomal proteins contents while upregulated proteins involved in glycolysis, oxidative phosphorylation, and the pentose phosphate pathway in cells. The ratios of NADPH/NADP+ and NADH/NAD+ were increased when cells responded to vanillin stress. The differentially expressed proteins perturbed by YRR1 deletion were much more abundant than and showed no overlaps with transcriptome changes, indicating that Yrr1 affects the synthesis of certain proteins. Forty-eight of 112 upregulated proteins were involved in the stress response, translational and transcriptional regulation. YRR1 deletion increased the expression of HAA1-encoding transcriptional activator, TMA17-encoding proteasome assembly chaperone and MBF1-encoding coactivator at the protein level, as confirmed by ELISA. Cultivation data showed that the overexpression of HAA1 and TMA17 enhanced resistance to vanillin in S. cerevisiae. Conclusions Cells conserve energy by decreasing the content of ribosomal proteins, producing more energy and NAD(P)H for survival in response to vanillin stress. Yrr1 improved vanillin resistance by increasing the protein quantities of Haa1, Tma17 and Mbf1. These results showed the response of S. cerevisiae to vanillin and how YRR1 deletion increases vanillin resistance at the protein level. These findings may advance our knowledge of how YRR1 deletion protects yeast from vanillin stress and offer novel targets for genetic engineering of designing inhibitor-resistant ethanologenic yeast strains.