China Coal Research Institute (China)

Long-distance coal gangue slurry transportation pipelines are critical components of underground coal mine green backfilling systems, yet blockage failures severely threaten their safe and efficient operation. Existing distributed acoustic sensing (DAS)-based monitoring methods for such pipelines suffer from three key limitations: insufficient fixed-point quantitative accuracy, lack of verified blockage-specific characteristic indicators, and limited quantitative severity assessment capability. To address these gaps, this paper proposes a novel feature-level fusion monitoring method integrating DAS, fiber Bragg grating (FBG), and piezoelectric accelerometers for accurate blockage identification and quantitative evaluation in coal gangue slurry pipelines. A slurry pipeline circulation test platform with gradient blockage simulation (0% to 76.42%) and a synchronous multi-sensor monitoring system were developed. Through multi-domain signal analysis, three blockage-correlated characteristic frequencies were identified and cross-validated by synchronous multi-sensor data: 1.5 Hz (system background vibration), 26 Hz (blockage-induced fluid-structure resonance, verified by the Euler-Bernoulli beam theory with a theoretical value of 25.7 Hz), and 174 Hz (transient flow impact). The DAS phase change rate exhibited a unimodal nonlinear response to blockage degree, with the peak occurring at 40.94% blockage. On this basis, a sine-fitting quantitative inversion model was developed, achieving a high goodness of fit (R2 = 0.985), and leave-one-out cross-validation confirmed its excellent robustness with a mean relative prediction error of 3.77%. Finally, a collaborative monitoring framework was built to fully leverage the complementary advantages of each sensor, realizing full-process blockage monitoring covering global blockage localization, precise quantitative severity calibration, and high-frequency transient risk early warning. The proposed method provides a robust experimental and technical foundation for real-time early warning, precise localization, and quantitative diagnosis of long-distance slurry pipeline blockages and holds important engineering application value for the safe and efficient operation of underground coal mine green backfilling systems.

Perovskite solar cells (PSCs) have attracted considerable scientific interest due to their remarkable power conversion efficiency (PCE) and economically viable manufacturing processes. However, the commercialization has faced obstacles such as limited operational stability and susceptibility to moisture, which usually stem from the inferior quality of perovskite film. In this study, we present Di-p-toluenesulfonamide (D-pTSAD) as triple-functional ligand featuring multi-site synergistic coordination with the perovskite lattice. Through this mechanism, D-pTSAD simultaneously facilitates oriented crystal growth and mitigates defect formation, achieving a top-performing device with a PCE of 26.22%. Comprehensive analysis reveals that D-pTSAD forms stronger coordination with both Pb2 + and I- ions compared to bifunctional ligands, effectively passivating defects, suppressing ion migration, and reducing nonradiative recombination. After 1,000h of continuous maximum power point tracking, PSCs with D-pTSAD maintained 82.5% of initial PCE. This research underscores the potency of multisite coordination chemistry in elevating both performance and stability of PSCs.

Hepatocellular carcinoma (HCC) develops from chronic inflammatory conditions to malignancy, with the immune microenvironment playing a significant role in this progression. However, the changes in the dynamic immune microenvironment during the transition from hepatitis to HCC remain poorly understood. Systematic analysis of stage-specific immune microenvironment alterations is essential for identifying therapeutic targets and creating precision strategies for HCC. Using single-cell RNA sequencing (scRNA-seq), we created dynamic transcriptome maps of the immune microenvironment across healthy liver, hepatitis, cirrhosis, and HCC stages. Cell-cell communication, trajectory, and enrichment analyses were utilized to characterize relationships between clusters. TCGA-LIHC data were used to validate gene expression and its prognosis. The spatial distribution of ligand-receptor complexes in HCC was confirmed by spatial transcriptomics and multiplexed immunofluorescence. The effects of the tumor microenvironment on cancer cell behavior were examined using co-immunoprecipitation and cell co-culture assays. Finally, the impact of the immune microenvironment on in vivo tumor progression was evaluated using a mouse transplantation model. We identified specific immune cell clusters across HCC progression and revealed significant correlations between the abundance of immune cells (macrophages, B cells)and fibroblasts with disease severity. Crosstalk between SPP1+ macrophages and ITGA5+ fibroblasts was observed explicitly in HCC. In vitro and in vivo data demonstrated that the SPP1-ITGA5 interaction triggered the secretion of MMP2 by fibroblasts, thereby promoting malignant progression in HCC. We present a dynamic transcriptional profile of immune microenvironment evolution during HCC development, aiding in the refinement of diagnostics and the optimization of therapy strategies.

To facilitate the reuse of the gob-side retained entry as a long-term return airway, alleviate mining-excavation pressure, and reduce roadway development costs, this paper proposes a secondary gob-side entry retaining technique. The study examines the movement behavior of overlying strata throughout the entire process of secondary gob-side entry retaining, introduces a roof support concept based on “major and minor structural zones,” establishes a mechanical model of the roof structure for secondary retention, derives a design formula for the roadside backfill, analyzes the main factors influencing the stability of the overlying strata structure, and proposes an integrated “four-in-one” surrounding rock control technology for secondary gob-side entry retaining. The results indicate that: (1) The “major structural zone” of the overlying strata stabilizes only after experiencing three mining disturbances. (2) The coordinated load-bearing behavior of the “minor structural zone” in roof support is crucial to surrounding rock stability. A “four-in-one” control strategy is proposed, integrating the roadside packing bodies on both sides, the roof bolting-cable system, floor reinforcement, and internal roadway support to form a stable load-bearing structure. (3) Appropriately reducing the roadway width, the widths of the two packing bodies, and the cantilever length of the main roof on the goaf side can enhance the support capacity of the coal rib during the initial retention stage. This reduces the load on the packing bodies during the secondary gob-side entry retaining stage, thereby alleviating surrounding rock stress. The proposed approach has yielded favorable outcomes in engineering practice, demonstrating both theoretical relevance and practical significance for supporting roadways under similar conditions.