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Buildings account for approximately one-third of global energy consumption and greenhouse gas emissions. Accurate occupancy data is critical for enabling energy-efficient control strategies and enhancing comfort in buildings. However, most current research on multi-zone occupancy-centric control (OCC) relies on simulated rather than real-world occupancy data. Additionally, the optimal operational intervals of existing OCC-based HVAC systems have not been fully explored in dynamic indoor environments. This study presents an extensive experimental study evaluating the impact of multi-zone real-world OCC systems on energy conservation and comfort in a multi-zone building. We collected real-world occupancy data using vision-based methods and developed HVAC control strategies using operational intervals of 5, 10, 15, 30, and 60 min to evaluate their effects on energy efficiency and occupant comfort. Simulations were performed using OpenStudio with EnergyPlus. The results indicate that customized operational intervals significantly improve both energy efficiency and occupant comfort. Shorter intervals can provide effective energy savings in dynamic settings, while longer intervals yield improved comfort and energy efficiency in more stable environments. This study demonstrates the effectiveness of OCC systems in optimizing energy usage and comfort and sets the stage for future developments in building management strategies. Emerging trends, such as integrating large language models into OCC, are also discussed for future exploration. • Real-world 7-zone occupancy data captured via cameras for experimental studies. • Real-world rooms modeled in EnergyPlus with OpenStudio for simulations. • OCC systems improve energy efficiency and enhance occupant comfort. • Short HVAC control intervals fit dynamic conditions; longer ones fit stable settings. • Future trends include leveraging large language models for OCC applications. [ABSTRACT FROM AUTHOR]

In this study, Ag/CNTs composite films with excellent properties of surface-enhanced Raman scattering (SERS) were fabricated. The SEM images show that the template effect and stress concentration area of carbon nanotubes (CNTs) can not only induce the growth of Ag nanoparticles, but effectively increase the number and intensity of "hot spots". Due to the introduction of CNTs, the plasma absorption peak of Ag/CNTs composite films was observed to be enhanced in the range of visible light. The as-deposited Ag/CNTs samples showed high sensitivity and good temporal stability in the detection of MB probe molecules, with the detection limit of 10−9 mol/L and the enhancement factor of 6 × 105, respectively. In addition, the enhancement contribution of the substrate was further investigated by Finite difference time domain simulation, and the simulation results were consistent with those of the experimental results, which indicate that the synthesized Ag/CNTs thin films have potential application prospect in SERS technology. • Ag NPs self-assemble and grow on CNTs, leading to the formation of more "hotspots", which enhances the LSPR effect. • After 30 days of exposure to air, the Ag/CNTs samples exhibited excellent stability in SERS measurements of MB. • The detection limit of methylene blue can be reduced to 10−9 M in Ag/CNTs samples, with an EF of about 6 × 105. [ABSTRACT FROM AUTHOR]

Variable Air Volume (VAV) system is a typical time delay system with multiple variables, and it is difficult to build a dynamic response model for describing room temperature regulation process. This paper firstly proposes a novel model of dynamic response of room temperature based on the analytical solution of heat balance equation in VAV air conditioning zone. According to the solution, inertia time constant and magnification coefficient of room temperature response can be directly calculated by initial environmental parameters. The model is further extended to a Multi-Input Single-Output (MISO) model with airflow regulating actuators as input and room temperature as model output. Experimental studies are carried out to test practical supply airflow and room temperature response and corresponding model parameters are identified according to the measured data in the VAV experimental platform. The proposed identification method based on analytical solution is validated through simulation and compared with classical identification method. Results indicate that the proposed identification method could describe the room temperature dynamic characteristics of VAV system well, and it can be applied in control simulation and engineering application in future work. [ABSTRACT FROM AUTHOR]

Buildings substantially impact global energy usage and emit significant carbon dioxide. Building occupancy is crucial to enabling energy conservation in buildings and achieving zero emissions by 2050. While existing occupancy prediction methods have made remarkable progress, their analysis is limited to complex practical scenes. In addition, the expectations of Transformers are high for predicting building occupancy. To address these problems, we introduce Transformer algorithms for building occupancy number prediction. We publicly provide an actual operating dataset for 2 weeks in 6 zones, including multi-sensor sensing information (e.g., temperature, occupancy, relative humidity, FCU control, FCU fan feedback, and FCU on/off feedback). To evaluate the performance, we provide an experimental analysis and comparison among our Transformer-based occupancy prediction algorithm and different machine learning methods (e.g., random forest, decision trees, XGBoost, and long short-term memory networks). Our Transformer-based occupancy prediction algorithm performs better on our dataset than other existing algorithms. The code, dataset, and demo are available at https://github.com/kailaisun/occprediction. • A Transformer-based building occupancy number prediction algorithm was proposed. • A 2-week real operating multi-sensor occupancy dataset is available publicly. • Quantitative analyses and comparisons were conducted on our dataset. • Transformer-based algorithm achieved superior performance than 4 ML methods. [ABSTRACT FROM AUTHOR]

Characteristics and problem of building automation system (BAS) existed in the practical engineering application are analyzed, and then the development of BAS is discussed from the perspective of network structure and supplied function service. Aiming at the space distribution feature, this paper presents the network architecture of Ubi-bus fieldbus, and then essential feature, operation mechanism and standardized information model are introduced respectively. Software and hardware are designed and developed in the control platform of variable air volume (VAV) air conditioning system. Based on the network architecture of Ubi-bus, it is potential for the solution of BAS integration in the practice application. [ABSTRACT FROM AUTHOR]

Indoor temperature prediction is an essential component of building control and energy saving. Although existing indoor temperature prediction frameworks have achieved remarkable progress, they struggle to achieve high performance due to information, method, application, and sim-to-real gaps. Aiming to fill these gaps, we propose a novel deep-learning framework for short-term indoor temperature prediction in multi-zone buildings. In particular, we expand the sensing information and formulate the multi-zone indoor temperature prediction (MITP) problem. To improve the prediction performance, we employ information fusion and encoder–decoder architecture to the MITP problem and propose MITP-Net. We set up 11 ablation experiments to compare the prediction performance of relative frameworks. To evaluate frameworks' performance, we publicly release a dataset including 2-week real operating data in a multi-zone office with a 1-min sampling interval (829,440 digits in total). Compared with existing deep-learning frameworks, MITP-Net significantly raises the prediction accuracy and can flexibly adjust the lengths of input and prediction sequences for different requirements. We provide the usage steps of MITP-Net and publish the operating data and codes on the GitHub repository: https://github.com/XingTian1994/MITP-Net. • We formulate the MITP problem and propose a novel deep-learning prediction framework. • MITP-Net utilizes a two-stage information fusion method for multi-modal data. • MITP-Net adopts the encoder–decoder architecture for variable sequences length. • We publicly release a real multi-zone office dataset and verify MITP-Net. • MITP-Net significantly improves the performance compared to existing methods. [ABSTRACT FROM AUTHOR]

Building occupancy information is essential for energy saving, comfort improvement, and security management. Existing vision-based indoor occupancy measurement methods have achieved remarkable progress; however, they mainly focus on single-vision situations, i.e., cameras at room entrances or interiors. These methods struggle to achieve high accuracy because of the complex indoor environments. For example, they often fail to detect occupants and generate many false positives. In this paper, to address these issues, we propose a novel fusion framework for occupancy detection and estimation based on two different perspectives. First, we design a head detection method combined with indoor scene knowledge to filter false positives and recover missed detection. Second, we propose a two-vision entrance counting method to refine the predicted results. Finally, we propose a cumulative error clearing strategy named dynamic Bayesian fusion (DBF), which integrates entrance counting and static estimation. Our framework achieves superior performance through ablation studies compared to existing methods on practical building surveillance videos, with occupancy estimation SCOREs of 99.2%, 98.5%, and 94.9%. Our framework can clear cumulative errors and stabilize estimation results. Practical experiments validate its potential for building energy saving and comfort improvement. The code is available at https://github.com/kailaisun/FFO. • Fusion framework improves the performance of vision-based occupancy estimation. • Heterogeneous visual information does contribute to perception of occupancy. • DBF can clear cumulative errors; LCM can stabilize shaking results. • Quantitative & qualitative analyses were conducted on practical surveillance videos. • Experiments validated its potential for energy saving and comfort improvement. [ABSTRACT FROM AUTHOR]

Many studies have shown that glutamate-induced oxidative stress can lead to neuronal cell death involved in the development of neurodegenerative diseases. In this work, protective effects of ethyl acetate extract (EAE) of Arctium lappa L. roots against glutamate-induced oxidative stress in PC12 cells were evaluated. Also, the effects of EAE on antioxidant system, mitochondrial pathway, and signal transduction pathway were explored. Pretreatment with EAE significantly increased cell viability, activities of GSH-Px and SOD, mitochondrial membrane potential and reduced LDH leakage, ROS formation, and nuclear condensation in a dose-dependent manner. Furthermore, western blot results revealed that EAE increased the Bcl-2/Bax ratio, and inhibited the up-regulation of caspase-3, release of cytochrome c, phosphorylation of p38, c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinase 1/2 (ERK 1/2). Therefore, our results indicate that EAE may be a promising neuroprotective agent for the prevention and treatment of neurodegenerative diseases implicated with oxidative stress. [ABSTRACT FROM AUTHOR]

Previous studies have demonstrated that chronic periodontitis (CP) is closely associated with the occurrence and development of a variety of systemic diseases. In this study, we successfully constructed a rat CP model through dental silk ligation, and the corresponding inflammatory reactions and fatty lesions were observed in the liver. Sprague-Dawley rats (n = 6) underwent tooth ligation at the bilateral first molars with silk thread to induce CP and were sacrificed 8 weeks later and compared to non-ligated rats (n = 6). RNA sequencing and 16S rRNA analysis were performed to determine the molecular mechanisms of CP involved in inducing liver disease. Alveolar bone loss, liver enzymes, mandible and liver histopathology, and inflammatory responses were compared between groups. RNA sequencing of liver tissue showed that the expression of SCD1 increased significantly in CP rats compared to controls. KEGG enrichment analysis showed that the AMPK signalling pathway may be involved in liver steatosis. The intestinal flora of faecal samples of rats were analysed by 16S rRNA sequencing, and the results indicated that the intestinal flora of the CP group was evidently imbalanced. The expression levels of tight junction proteins (ZO-1, occludin, and claudin-1) were significantly reduced in CP rats. Meanwhile, increases in serum IL-1β and lipopolysaccharide in CP rats reflected a systemic inflammatory response. CP may be involved in the occurrence and development of hepatic injury and liver steatosis, and its mechanism may be related to the oral-gut-liver axis and SCD1/AMPK signal activation in the liver. [ABSTRACT FROM AUTHOR]

[Display omitted] • MEC and CBC are combined to upgrade cow-manure-based anaerobic co-digestion. • MEC 0.6 CBC 0.15 improves the methane yield by 120.68% and COD removal rate by 58.33%. • MEC with CBC demonstrates an excellent electrochemical activity. • Digestates exhibit an acceptable thermal stability and fertilizer efficiency. • A general strategy to understand enhanced performance of MEC with CBC is proposed. Microbial electrolysis cells (MECs) and exogenous accelerants can augment anaerobic digestion performance. Herein, MECs and coconut-shell-derived bio-based carbon (CBC) accelerant are adopted to strengthen anaerobic co-digestion of cow manure and aloe peel waste. The MEC with the voltage of 0.6 V and CBC accelerant of 0.15 wt.% gained the highest cumulative biogas yield (444.20 NmL/g VS) and chemical oxygen demand removal rate (75.46%), which are 80.25% and 58.33% higher than those (246.44 NmL/g VS, 47.66%) of the blank group, respectively. The digestates embodied a utilization potential with thermogravimetric loss of 37.12%–50.67% and total nutrient content of 35.36–51.58 g/kg. These results benefited from excellent electrocatalytic activity of MECs and physicochemical properties of CBC accelerant. A general strategy for understanding improved methanogenesis was proposed based on integrated effects of MECs and CBC accelerant. This work will shed light on development of anaerobic co-digestion by combining MECs and bio-based carbon accelerants. [ABSTRACT FROM AUTHOR]

Background: Acute kidney injury (AKI), characterised by excessive inflammatory cell recruitment and programmed cell death, has a high morbidity and mortality; however, effective and specific therapies for AKI are still lacking.Objective: This study aimed to evaluate the renoprotective effects of gypenoside XLIX (Gyp XLIX) in AKI.Methods: The protective effects of Gyp XLIX were tested in two AKI mouse models established using male C57BL/6 mice (aged 6-8 weeks) by a single intraperitoneal injection of cisplatin (20 mg/kg) or renal ischemia-reperfusion for 40 min. Gyp XLIX was administered intraperitoneally before cisplatin administration or renal ischemia-reperfusion. Renal function, tubular injury, renal inflammation and programmed cell death were evaluated. In addition, the renoprotective effects of Gyp XLIX were also evaluated in cisplatin- or hypoxia-treated tubular epithelial cells. The mechanisms underlying these effects were then explored using RNA sequencing.Results: In vivo, Gyp XLIX substantially suppressed the increase in serum creatinine and blood urea nitrogen levels. Moreover, tubular damage was alleviated by Gyp XLIX as shown by periodic acid-Schiff staining, electron microscopy and molecular analysis of KIM-1. Consistently, we found that Gyp XLIX suppressed renal necroptosis though the RIPK1/RIPK3/MLKL pathway. The anti-inflammatory and antinecroptotic effects were further confirmed in vitro. Mechanistically, RNA sequencing showed that Gyp XLIX markedly suppressed the levels of IGF binding protein 7 (IGFBP7). Co-immunoprecipitation and western blot analysis further showed that Gyp XLIX reduced the binding of IGFBP7 to IGF1 receptor (IGF1R). Additionally, picropodophyllin, an inhibitor of IGF1R, abrogated the therapeutic effects of Gyp XLIX on cisplatin-induced renal cell injury; this finding indicated that Gyp XLIX may function by activating IGF1R-mediated downstream signalling Additionally, we also detected the metabolic distribution of Gyp XLIX after injection; Gyp XLIX had a high concentration in the kidney and exhibited a long retention time. These findings may shed light on the application of Gyp XLIX for AKI treatment clinically.Conclusion: Gyp XLIX may serve as a potential therapeutic agent for AKI treatment via IGFBP7/ IGF1R-dependent mechanisms. [ABSTRACT FROM AUTHOR]

• Four transition metal oxides promote the anaerobic digestion by enhanced DIET. • First-principle calculations illustrate the metallic feature of accelerants. • Mediated electrochemical tests verify an electron exchange capacity of accelerants. • Microbial community confirms the syntrophic bacteria in anaerobic digestion. • A universal strategy for understanding the enhanced DIET is proposed. Transition metal compounds have been widely used to enhance the anaerobic digestion (AD) performance, while the role of transition metal compounds in enhancing AD performance remains unclarified. In this work, the function of transition metal oxide accelerants (tantalum oxide, niobium oxide, hafnium oxide, and tungsten oxide) in enhanced AD systems was investigated from experimental and theoretical standpoints. Higher biogas production (565.01–617.85 mL/g VS), chemical oxygen demand degradation rate (67.17%-70.45%), total solids and volatile solids reduction rates (29.76%-34.71%, 51.83%-60.88%) were achieved in AD systems with transition metal oxide accelerants than the control (327.08 mL/g VS, 56.65%, 22.65%, and 41.18%). The first-principle density functional theory calculations, electron exchange capacity analysis, and the 16S rRNA gene pyrosequencing demonstrated superior electron transfer and exchange capacities as well as microbial consortia development in transition metal oxides-induced DIET mechanism. This work provides a promising strategy for understanding the function of high-performance accelerants in AD systems. [ABSTRACT FROM AUTHOR]

The Buildings Global Status Report (Buildings-GSR) highlights the significant impact of the buildings and construction sector on global climate change. This sector is responsible for approximately 34% of global energy consumption and 37% of carbon dioxide (C O 2) emissions. Smart building is a promising solution to achieve Zero Net goals. High-accuracy occupancy counting plays a crucial role in enhancing building energy efficiency, improving environmental comfort, and reducing disease transmission. Occupancy information can serve as feedback in a closed-loop building control strategy, enabling occupant-centric control (OCC). Even though existing studies have made developments, they struggle to obtain high-accuracy occupancy counting because of many challenges, e.g., cumulative errors and occlusion. To address these challenges, a novel deep learning-based occupancy counting method by edge cameras at crowded entrances is introduced. We annotate the occupancy tracking dataset and train tracking neural networks to count occupants, achieving 80.4% and 69.9% MOTA in two different cameras. We fuse multi-camera information to achieve high performance. Our methods achieve an occupancy counting accuracy of approximately 98.1% with two real-scene surveillance cameras, surpassing the existing occupancy counting methods by 7.7%. Besides, we design an occupant-centric control method to save energy in buildings. Our experiments demonstrate that our occupancy counting method achieves better performance on a real-world dataset, compared to other methods. Our experiments verify that our occupant-centric control method has the potential for building energy saving about 17%-25% in a room. Our study deepens the insights into occupancy measurement, paving the way toward energy-efficient buildings and comfortable indoor environments. We make our code available at https://github.com/kailaisun/Head-tracking-for-occupancy-counting. [ABSTRACT FROM AUTHOR]

This study utilized two-sample Mendelian randomization (TSMR) to investigate the bidirectional causal associations between temporomandibular disorders (TMD) and five mental disorders. Single-nucleotide polymorphisms (SNPs) linked to TMD were extracted from the Genome-Wide Association Studies (GWAS) database. The SNPs selected as instrumental variables (IVs) were required to have strong associations with the exposure phenotype and to meet the assumptions of Mendelian randomization (MR) analysis. The primary method employed for TSMR analysis was the Inverse Variance-Weighted (IVW) method. Additionally, the Weighted Median, Weighted Mode, and MR Egger methods were used as secondary approaches to ensure the reliability and credibility of the results. Furthermore, heterogeneity, pleiotropy, and sensitivity tests were conducted to ensure the accuracy and robustness of the findings. After MR analysis, we performed reverse analysis to explore the bidirectional association between TMD and five mental disorders. Our study provided evidence of a positive correlation between TMD and both anxiety (P = 5.94 × 10−15, OR = 1.5253, 95 % CI = 1.3719–1.6959) and depression (P = 3.79 × 10−12, OR = 1.4243, 95 % CI = 1.2890–1.5738). In the reverse TSMR analysis, a positive association was found between anxiety and TMD (P = 0.0126, OR = 1.0664, 95 % CI = 1.0139–1.1217). However, no causal relationship was found between TMD and depression, insomnia, bipolar disorder, or schizophrenia (P > 0.05). These evidences indicated a bidirectional relationship between TMD and anxiety, and TMD may also contribute to the development of depression. [Display omitted] • TMD has a bidirectional causal association with anxiety. • Depression is positively correlated with TMD but not in the reverse analysis. • It reveals no causal association between TMD and other mental disorders. [ABSTRACT FROM AUTHOR]

• Introduction of binary and ternary TEs can improve biogas yield by 66.52–76.32%. • Three kinetic models (FOM, LM, and MGM) are employed to predict biogas yield. • Predicted data (0.32–5.3%) of LM and MGM are closer to measured data than FOM. • Coats-Redfern fitting proves TEs reduce activation energy of digestate (3.9–26.2%). • The selected kinetic models fit well with the experimental data (R2 > 0.98). The effects of binary and ternary trace elements (TEs) (Fe/Co, Fe/Ni, and Fe/Co/Ni) on the anaerobic digestion (AD) of cattle manure were investigated using kinetic models (first-order, logistic, modified Gompertz, and Coats-Redfern) and experimental measurements. Binary and ternary TEs can significantly improve the biogas production rate and yield potential. The deviation between the predicted and measured data for biogas yield with logistic model (2.1%–5.3%) and modified Gompertz model (0.32%–2.9%) was smaller than that with first-order kinetic model (6.9%–9.9%). The Coats-Redfern model fitting indicated that the activation energy of digestates with trace elements during pyrolysis was reduced by 3.9%–26.2% compared with the control group. Meanwhile, digestates with TEs showed remarkable fertility (5.72%–5.95%). The combination of kinetic models and experimental measurements can effectively quantify the effect of TEs on AD performance and provide an informed choice for industrial production. [ABSTRACT FROM AUTHOR]

• Zigzag channels with bending angle 30° are studied experimentally. • Empirical correlations are proposed for friction factor and Nusselt number. • Fanning factor in this study is about 7–10 times that in straight channels. • Nusselt number in this study is about twice that in straight channels. Zigzag-channel printed circuit heat exchangers have a wide range of application prospects in Gen-IV nuclear systems related to supercritical carbon dioxide Brayton cycles. Experimental data and empirical correlations are the basis for the design of zigzag-channel printed circuit heat exchangers. In this study, experimental investigation on flow and heat transfer of supercritical carbon dioxide in zigzag channels is carried out. The dimensions of the tested zigzag channels are as follows, the channel diameter 1.95 mm, the bending angle 30°, the longitudinal pitch 7.24 mm, as well as the radius of the curvature at the bending corner 0.5 mm. The Reynolds number and Prandtl number of supercritical carbon dioxide in the experimental study range between 3201 and 43258 and 1.1–6.0, respectively. Based on the obtained local Fanning friction factors and local Nusselt numbers, the effect of zigzag angle on flow and heat transfer are analyzed. And new flow and heat transfer correlations for the tested zigzag channel are proposed. The predicted values by the new developed correlations agree with the experimental data well. Comparisons between the new developed correlations and the existing correlations developed for printed circuit heat exchangers are conducted. Heat transfer enhancement obviously occurs when comparing with straight channels. Result shows that the heat transfer coefficient in the tested zigzag channels is about twice that predicted by Dittus-Boelter correlation (under cooling condition). The Fanning friction factor in the tested zigzag channel is about seven to ten times that in straight channels within the scope of investigated. [ABSTRACT FROM AUTHOR]

The microscopic origin of the remarkable optoelectronic properties of one of the most studied contemporary materials remains unclear. Here, we identify the existence of magnetic interactions between intermolecular proton orbitals in CH 3 NH 3 PbI 3 and CH 3 NH 3 PbBr 3. In particular, a unique sharp drop and a pronounced step-up discontinuity in the magnetic susceptibility at the tetragonal-to-cubic phase transitions are identified in CH 3 NH 3 PbI 3 and CH 3 NH 3 PbBr 3 , respectively. The magnetic interactions in the orthorhombic and tetragonal phases are dependent on thermal history and lattice orientation while nearly independent of the applied external magnetic field. In CH 3 NH 3 PbBr 3 , the CH 3 and NH 3 + components reorient in an uncorrelated fashion resulting the cubic phase to also exhibit magnetic anisotropy. Our findings provide a potential link connecting the highly light-absorbing CH 3 NH 3 + and the exceptional properties of the charge carriers of the inorganic framework in hybrid perovskite solar cells. [Display omitted] [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.cogpsych.2010.01.003 Byline: Xing Tian (a), David E. Huber (b) Keywords: Semantic satiation; Reading; Discounting; Habituation; Repetition priming; Semantic priming; Lexical representation; Semantic processing; Categories; Semantic retrieval Abstract: How is the meaning of a word retrieved without interference from recently viewed words? The ROUSE theory of priming assumes a discounting process to reduce source confusion between subsequently presented words. As applied to semantic satiation, this theory predicted a loss of association between the lexical item and meaning. Four experiments tested this explanation in a speeded category-matching task. All experiments used lists of 20 trials that presented a cue word for 1s followed by a target word. Randomly mixed across the list, 10 trials used cues drawn from the same category whereas the other 10 trials used cues from 10 other categories. In Experiments 1a and 1b, the cues were repeated category labels (FRUIT-APPLE) and responses gradually slowed for the repeated category. In Experiment 2, the cues were nonrepeated exemplars (PEAR-APPLE) and responses remained faster for the repeated category. In Experiment 3, the cues were repeated exemplars in a word matching task (APPLE-APPLE) and responses again remained faster for the repeated category. Author Affiliation: (a) Neuroscience and Cognitive Science Program, Department of Psychology, University of Maryland, College Park, MD 20742, United States (b) Department of Psychology, University of California, San Diego, La Jolla, CA 92093-0109, United States Article History: Accepted 21 January 2010

• Combined effect of SMF and FA accelerant is firstly investigated in AD systems. • Combining FA accelerant and SMF can increase biogas yield by 35.55%. • Total nutrient contents in digestate are increased with FA accelerant and SMF. • The DIET is improved with combined effect of SMF and FA accelerant. • Mechanism of SMF coupled with FA in AD systems is illustrated. The anaerobic-co-digestion (AcoD) of dairy-manure (DM) and aloe-peel-residue (ALR) waste is enhanced by combining static-magnetic-field (SMF) and fly-ash (FA). Varying SMF intensities (5–30 mT) were applied to the co-digestion digesters containing the optimum FA concentration (1.5 wt.%), which were selected from co-digestion systems with a varying FA (0–2 wt.%). All experimental groups exhibit the greater COD removal rates (51.56–64.19%) and cumulative biogas yields (604.14–671.64 mL/g VS) than reference group (37.77% and 433.19 mL/g VS). The digester with optimum FA concentration (1.5 wt.%) under 5 mT shows the highest biogas yield (671.64 mL/g VS), and exhibits superior digestate stability (45.4%) and fertility (7.01%) for fertilizer utilization. A powerful strategy for understanding the underlying mechanism of the SMF and FA accelerant in an enhanced AcoD system is proposed. This work documents an innovative technique for an enhanced AcoD system using the SMF coupled with FA accelerant. [ABSTRACT FROM AUTHOR]

• Magnetic field and Ti-sphere core–shell structured additives are firstly used in AD. • Optimized 5 mT magnetic field intensity exhibits a positive effect in AD systems. • The Ti-2 MF-5 increases the biogas yield by 65.53% as compared with the CK. • Enhanced performance is due to the synergistic effect of magnetic field and additive. • A general strategy for understanding enhanced methanogenesis pathway is proposed. Enhancing anaerobic digestion performance is highly desired for its large-scale application. In the present work, magnetic fields (0–30 mT) and Ti-sphere core–shell structured additives (Ti-1 and Ti-2) are simultaneously introduced in anaerobic mono-digestion and co-digestions. Compared with the control group, the Ti-sphere core–shell structured additives increase the biogas yield by 27.12%–65.53% for mono-digestion and 8.47%–35.89% for co-digestion systems under the optimized magnetic field intensity (5 mT), respectively. Meanwhile, the degradation rate of total chemical oxygen demand is 54.68%–69.14% for anaerobic mono-digestion and 53.03%–78.25% for anaerobic co-digestion with Ti-sphere core–shell structured additives, respectively. The digestate with Ti-sphere core–shell structured additives exhibits the remarkable stability (45.24%–53.17%) and fertility (4.85%–4.97%). This work clarifies the effect of magnetic field in AD system, and proposes a possible mechanism for understanding the enhanced methanogenesis pathways induced by Ti-sphere core–shell structured additives. [ABSTRACT FROM AUTHOR]

• Biomass-derived carbon-based composites are firstly used as accelerants in AD system. • Composite accelerants effectively enhance the biogas yield by 34.2% in AD system. • The digestate with accelerants shows the total nutrient content of 3.50–4.55%. • A general strategy for understanding the DIET mechanism of accelerants is proposed. • The first-principle DFT calculations provide the theoretical basis for the DIET. The performance of anaerobic digestion (AD) can be improved by the addition of accelerants. Three types of biomass-derived carbon-based composites (Co/C, CoO/C, and Co 3 O 4 /C) were used as accelerants to investigate the effect on AD systems in this work. These accelerants significantly improved the cumulative biogas yield (576–585 mL/g VS), and the total chemical oxygen demand degradation rate (68.48–71.11%) compared to the reference group (435.8 mL/g VS, 50.74%). The digestates with accelerants exhibited exceptional stability (59.24–63.67%) and superior fertilizer utilization (3.50–4.55%). In addition, first-principle density functional theory (DFT) calculations were conducted to provide the theoretical basis for the direct interspecies electron transfer (DIET), and a general strategy was proposed to help understand the enhanced methanogenesis pathway induced by the biomass-derived carbon-based composites. These important findings provide a novel avenue for the development of composite accelerants for AD systems. [ABSTRACT FROM AUTHOR]