Lingfeng Zhao

Shale gas production dynamics display strong heterogeneity and nonlinearity, posing challenges to conventional analytical methods. This study applies fractal theory to analyze long-term production data from 178 global shale gas fields by calculating Hurst exponent (H) and fractal dimension (D). Results show 60.7% of fields are suitable for fractal analysis, with H values of 0.64–0.92 and D values of 1.0–1.9, indicating significant long-term memory and structural complexity. Cluster analysis reveals two distinct production patterns: stable trend (13.0%) and fluctuating trend (87.0%). Key innovations include: (1) extending fractal theory from static reservoir characterization to dynamic production analysis; (2) establishing a fractal-based production classification system; and (3) defining applicability conditions for fractal analysis in shale gas evaluation. This study demonstrates fractal theory’s effectiveness as a quantitative tool for production dynamics analysis, EUR estimation, and development strategy optimization.

Bio-gels are a class of functional polymeric materials with three-dimensional network structures. Their exceptional biocompatibility, biodegradability, high specific surface area, and tunable physicochemical properties make them highly promising for environmental remediation. This article systematically reviews the classification of bio-gels based on source, cross-linking mechanisms, and functional attributes. It also elaborates on their fundamental properties such as porous structure, high water absorbency, stimuli-responsiveness, and mechanical stability and examines how these properties influence their environmental remediation efficiency. This review comprehensively analyze the mechanisms and efficacy of bio-gels in adsorbing heavy metal ions, removing organic dyes, improving soil water retention, and restoring ecosystems. Special attention is given to the interactions between surface functional groups and contaminants, the role of porous structures in mass transfer, and the ecological effects within soil–plant systems. Additionally, this review explores extended applications of bio-gels in medical tissue engineering, controlled release of drugs and fertilizers, and enhanced oil recovery, highlighting their versatility as multifunctional materials. Finally, based on current progress and challenges, this review outline key future research directions. These include elucidating microscopic interaction mechanisms, developing low-cost renewable feedstocks, designing multi-stimuli-responsive structures, improving long-term stability, and establishing full life-cycle environmental safety assessments. These efforts will help advance the efficient, precise, and sustainable use of bio-gels in environmental remediation, offering innovative solutions to complex environmental problems.