Propionate is a key intermediate in anaerobic digestion (AD), and its accumulation may lead to over-acidification and process failure. This study assessed methanogenic tolerance to increased propionate concentrations. The specific methane yield ranged from 238.0 to 277.3 mL/g COD at the initial propionate concentration of 2 to 10 g COD/L, and slightly decreased to 260.6 and 233.3 mL/g COD at 13 and 16 g COD/L, respectively. Kinetic analysis indicates lower inoculum-to-substrate ratio primarily negatively affected digestion time rather than accumulated methane yield. No clear inhibition occurred, even at 16 g COD/L, indicating a substantial propionate tolerance in AD. 16S rRNA gene analysis revealed that Desulfobacterota, particularly the family Syntrophobacteraceae was positively associated with propionate degradation, showing a linear correlation (p < 0.01) with both initial propionate concentration and digestion duration. Genome-centric metagenomic analysis further identified Bin.002 (Syntrophobacteraceae JABUEY01) and Bin.012 (Syntrophobacteraceae sp.) as dominant syntrophic populations, exhibiting high RPKM abundance and encoding the complete methylmalonyl-CoA (mmc) pathway. A metabolically diverse methanogenic community was also enriched, including aceticlastic Methanosarcina mazei (Bin.006), Methanothrix spp. (Bin.009 and Bin.014), and hydrogenotrophic Methanobacterium spp. (Bin.011 and Bin.026), which rapidly consumed metabolic intermediates, thereby avoiding inhibition at high propionate concentrations. Overall, the batch experiments demonstrated strong propionate tolerance under stable anaerobic conditions, supporting the conclusion that propionate accumulation is more likely a consequence rather than a primary cause of anaerobic reactor imbalance.
Adsorptive separation of propane and propylene represents a promising technology in the chemical industry for propylene purification with low energy consumption. Carbon molecular sieves hold particular promise in light of their high stability, facile regeneration, and low cost. However, fine engineering of the pore size of carbon molecular sieves remains a notable challenge due to their amorphous nature. Here, we report the synthesis of a PAEK‐N polymer, which is used as a precursor for the preparation of PAEK‐N‐derived carbon molecular sieves (PCMSs). We show, through adjusting the carbonization process, that the pore dimensions as well as the gas adsorption performance of these PCMSs can be effectively regulated. Specifically, PCMS‐700, carbonized at 700°C, exhibits a high C 3 H 6 adsorption capacity of 47.4 cm 3 /g at 303 K and 1 bar while fully excludes C 3 H 8 , enabling precise size‐sieving of C 3 H 6 and C 3 H 8 . The separation capability was further validated through dynamic breakthrough experiments.
This overview presents AIEgens integrated with phthalocyanines and subphthalocyanines, summarizing how the conversion of aggregation-caused quenching to aggregation-induced emission-active systems enhances their emission-related applications.
A novel film-driven stretching device has been developed to more accurately simulate ocular accommodation. This device utilizes a rubber film stretcher that adheres to the ciliary body of enucleated porcine eyes, delivering uniform 360° radial traction to the lens through the zonular fibers. The anterior globe is stabilized, and the ciliary body is securely fixed using a dissection support base equipped with a Kimwipe featuring a central circular aperture and a pair of inter-fitting rings. This configuration facilitates rapid and reproducible preparation while maintaining lens transparency. A pre-stretching protocol has been established to reduce baseline zonular tension, allowing investigation across the full physiological accommodative range. The stretcher is installed in a modified 6‑well culture plate equipped with a micrometer to control the stretching level, rendering the system compatible with conventional laboratory equipment. A modified Topcon LM-8 manual lensmeter is employed to measure the refractive power of the porcine lens at various stretching levels. The mean change in dioptric power between the unstretched state (micrometer setting: 0 mm) and a stretching displacement of 1.5 mm is 1.47 ± 0.18 D. Compared to conventional multi-arm stretching systems, this film-driven stretcher features a simpler structure, provides more physiologically relevant radial traction, and is compatible with a wide range of analytical techniques. This compact setup provides an enhanced experimental tool for investigating the biomechanics and optical behavior of the crystalline lens during accommodation.
The sea level anomaly (SLA) has been accurately tracked by satellite altimetry, yet its barotropic and depth-integrated baroclinic components are routinely interpreted using theoretical or modeled vertical structures. In this study, we utilized manometric SLA from the Gravity Recovery and Climate Experiment (GRACE) and steric SLA from observational and reanalysis temperature/salinity databases to evaluate their roles in seasonal variations of geostrophic velocity anomalies and eddy kinetic energy (EKE) in the South China Sea (SCS). Through the empirical orthogonal function analysis, we found that the manometric component of geostrophic velocity anomalies is closely associated with the western boundary current, reflecting a barotropic response to seasonally reversed wind stress in summer and winter. The steric component, primarily driven by baroclinic instability, shapes two large cyclonic (anticyclonic) gyres (Luzon and Nansha Gyres) in the northeastern and southern SCS during summer (winter), as well as small mesoscale anomalies in the northwestern SCS during spring and autumn. The cross-correlation analysis demonstrates considerable influence of wind stress on the surface dynamics throughout SCS, while wind stress curl predominantly contributes to the gyres and dipole system off the Vietnamese coasts. Opposing covariances between manometric and steric EKE along the eastern deep and western shelf sides of the southwestern continental slope were investigated via vertical density, temperature, and salinity anomalies along three transects. These patterns arise from seasonally distinct horizontal and vertical mixing structure in upper-layer and near-bottom cross-shelf currents, providing observational evidence for significant interactions between baroclinic and barotropic instabilities in coastal regions.
