Abstract The development of eco-friendly intelligent packaging has attracted considerable attention due to increasing concerns regarding food safety and environmental sustainability. In this study, an intelligent packaging film based on canna starch reinforced with microcrystalline cellulose (MCC) derived from golden melon peel ( Cucumis melo L.) and incorporated with roselle ( Hibiscus sabdariffa L.) anthocyanin extract (RAE) was developed as a pH-responsive freshness indicator for vannamei shrimp ( Litopenaeus vannamei ). The isolated MCC exhibited a crystallinity index of 64.45 %, confirming successful removal of amorphous regions. RAE incorporation imparted pH-sensitive color-changing properties, transitioning from red/orange under acidic to yellow-green under alkaline conditions. Visual observation during shrimp storage revealed that the 0.06 % RAE film exhibited the earliest color response, with visible edge discoloration at 12 h corresponding to TVB-N levels approaching the safety threshold (24.89 ± 0.37 mg N/100 g), while 0.02 % and 0.10 % RAE films showed no visible changes at the same time point. Increasing RAE concentration increased film thickness, moisture content, elongation at break, and water vapor permeability, while reducing tensile strength and water solubility. TVB-N and pH measurements confirmed shrimp remained fit for consumption up to 12 h at room temperature. The developed films demonstrate strong potential as sustainable intelligent packaging for real-time freshness monitoring of vannamei shrimp.
Abstract Against the backdrop of the global energy transition toward green and low-carbon development, the exploitation of unconventional oil and gas resources has become a strategic priority worldwide. This critical review systematically summarizes the state-of-the-art progress of high-temperature, eco-friendly water-based drilling fluids (WBDFs), with a focused discussion on three core categories of functional additives: modified natural polymers, synthetic polymers, and organic–inorganic nanocomposites. Natural polysaccharides (e.g., guar gum, xanthan gum) achieve improved thermal stability through functional group grafting and hydrophobic association modification. Synthetic polymers – especially zwitterionic polyelectrolytes and amphiphilic copolymers – deliver outstanding performance in high-temperature and high-salinity (HT/HS) environments, benefiting from rigid carbon backbones and self-charge compensation mechanisms. Nanostructured biopolymers and polymer-nano hybrid networks collectively enhance thermal endurance, salt tolerance, and shear resistance. This work clarifies standardized scaling rules for converting laboratory-measured WBDF performance metrics to field engineering practice, and characterizes typical HT-triggered performance deterioration behaviors of the three additive families. Representative eco-friendly fluid systems, including HPWBM, MEG-WBM, and synthetic-based drilling fluids, have achieved successful field deployment in shale-gas horizontal wells and deepwater drilling projects. Green nanocomposites maintain uniform dispersion and favorable interfacial compatibility under extreme HT/HS conditions. Future research directions are proposed as follows: developing intrinsically heat-resistant materials with thermal tolerance exceeding 200 °C; optimizing nanocomposite interfaces via three core technical routes (nanoparticle surface functionalization, silane coupling agent modification, and core–shell structural construction); and developing digitally intelligent adaptive WBDF design frameworks.
Abstract This document gives definitions of terms related to computational and modeling studies of polymeric materials. The terms and methods covered by this document are characterized by different degrees of resolution, such as molecular dynamics and Monte Carlo simulations of both atomistic and coarse-grained polymer models. Most of the terms defined herein apply to particle-based methods, which retain at least some degree of molecular-level information. Thus, continuum-level theories and computational methods are excluded, while electronic structure methods are included to some extent. Modeling of polymerization and other chemical reactions are excluded. The list is restricted to the most commonly encountered terms.
Abstract Food waste remains a significant issue globally, often driven by misinterpretation of expiration dates, resulting in the disposal of still-edible food. Intelligent food packaging offers a solution by monitoring food freshness through observable colour changes. As the freshness of protein-based foods deteriorates, gases like NH 3 will be released as a result of protein degradation, making NH 3 a reliable target analyte for monitoring food freshness. Polyaniline (PANI), with its ability to change colour based on oxidation states, offers a promising approach for freshness detection. However, its application as intelligent food packaging is restricted by poor mechanical properties and non-biodegradability. In this study, PANI synthesized via chemical oxidative polymerization was incorporated into kappa-carrageenan (κ-CGN) to enhance functionality while maintaining environmental sustainability. κ-CGN/PANI film was exposed to varying NH 3 concentrations from 200 to 1000 ppm and temperatures from −20 °C to 40 °C. A visible colour change from green to blue occurred after 45 min, measured using the RGB model of ImageJ. κ-CGN/PANI 0.50 % showed the best performance with good sensitivity (0.00005), linearity (R 2 = 0.9945), precision (RSD = 1.50 %), and LOQ (638 ppm). Long-term stability and real sample analysis showed signal ranges of 1.0620–1.0957 and 1.0151–1.0215, showcasing the potential of κ-CGN/PANI film as an effective label-form intelligent food packaging for real-time freshness monitoring.
Abstract This study compared the metabolite composition and antioxidant capacity of acetone and methanolic extracts from the leaves (LAc and LMet) and twigs (Tac and TMet) of Araucaria bidwillii , with particular emphasis on biflavonoid profiling and quantification. LC-MS/MS analysis identified agathisflavone-, amentoflavone-, and cupressuflavone-type biflavonoids in both leaves and twigs. 7,4′,7″,4‴-Tetra- O -methylcupressuflavone and two unidentified metabolites were exclusively found in leaves, and kolaflavanone was detected only in twigs. Among all extracts, LAc exhibited the most diverse metabolite profile and the highest abundance of methylated biflavonoids. HPLC-DAD analysis confirmed that LAc contained the highest levels of target biflavonoids, with 7,4′,7″-tri- O -methylcupressuflavone being the predominant compound (0.2618 ± 0.0132 mg/g). LAc exhibited superior antioxidant performance in CUPRAC assays, whereas LMet showed the highest FRAP value. These findings indicate that antioxidant capacity is influenced not only by the total abundance of phenolic compounds but also by their qualitative composition, particularly the distribution of biflavonoids. Overall, the results demonstrate that acetone is more effective than methanol for recovering biflavonoid-rich fractions from A. bidwillii leaves. The combination of a diverse metabolite profile, high biflavonoid content, and strong antioxidant activity identifies LAc as the most promising extract for future bioactivity-guided isolation and pharmacological investigations of biflavonoids from A. bidwillii .
