Search Results (13,709)

Combined cooling, heating, and power (CCHP) tri-generation systems can greatly improve comprehensive energy utilization efficiency thanks to their energy-cascade utilization concept. However, traditional fossil-fuel-based CCHP systems still suffer from intensive carbon emissions, hindering their further development in the current low-carbon scenario. To solve this issue, a new low-carbon CCHP system (LC-CCHP) integrating a calcium-looping, sorption-enhanced steam methane reforming (CL-SE-SMR) unit, a lithium bromide absorption chiller, and a hydrogen gas turbine is proposed in this work, and the corresponding system model is built to evaluate its performance. The proposed system features an innovative architecture that integrates carbon capture directly into the reforming process, which simultaneously enables a high hydrogen yield and low carbon-capture penalty. Moreover, instead of the widely used thermodynamic equilibrium assumption, a detailed kinetic model is employed for the CL-SE-SMR unit, which provides more realistic predictions and greater reference value for practical engineering applications. Then, multi-objective optimization is conducted using a particle swarm optimization algorithm to identify the optimal operating conditions. It is found that the proposed system performs best at a steam-to-carbon molar ratio of 4.37, a calcium-to-carbon mass ratio of 6.23, an air-equivalency molar ratio of 1.39 for a hydrogen gas turbine and a reaction temperature of 600 °C for SE-SMR. Under these operating conditions, the system can achieve a carbon-capture rate of 89.2%, an exergy efficiency of 45.7%, an energy efficiency of 95.4%, and a levelized cost of exergy of 0.109 $/kWh. Full article

Multimetallic layered double hydroxides (LDHs) are promising oxyanion sorbents, but their practical use requires evaluation of sorption efficiency and chemical stability. This study examined how introducing Cu²⁺ and Zn²⁺ into the LDH structure affects As(V) sorption, comparing binary Mg₃Al₁ and four-component Mg₂Cu_0.5Zn_0.5Al₁ in carbonate and chloride forms. The materials were synthesised by the co-precipitation method and characterised using XRD, FTIR, SEM, BET, and XPS, while their layer metal composition was determined by ICP-OES. The sorption studies were supplemented by chemical stability analysis (pH 4–11) and As(V) desorption experiments. Equilibrium data were evaluated using the Redlich–Peterson isotherm model. The four-component LDH showed higher As(V) sorption capacity than the conventional MgAl system, with the best performance observed for chloride forms: 37.5 mg/g for MgCuZnAl-LDH and 22.5 mg/g for MgAl-LDH. The sorption kinetics are well described by the pseudo-second-order and Elovich models, indicating a significant contribution from chemisorption. The results suggest that As(V) removal involves the combined action of anion exchange, electrostatic interactions and inner-sphere complex formation, controlled by the composition of the LDH layer and the type of interlayer anion. The introduction of Cu²⁺ and Zn²⁺ promoted additional active sites and stronger As(V) surface interactions. The results indicate that MgCuZnAl-LDH, particularly in the chloride form, exhibits promising As(V) sorption performance under model conditions involving a single solute. Full article

This work focuses on the combustion characteristics and kinetics of three building timber organic solid wastes (BTOSW)—China fir, Eucalyptus wood, and Pine wood—aiming to provide theoretical and data support for the thermal conversion and energy utilization of construction-derived woody biomass. Thermogravimetric analysis (TGA) reveals that all three materials exhibit two-stage combustion behavior: volatile combustion at low temperatures (<320 °C) and char combustion at high temperatures (320–500 °C). Increasing the heating rate shifts the decomposition peaks to higher temperature zones, reflecting the combined effects of thermal lag and shortened reaction time. Kinetic analysis shows that the correlation coefficients (R²) calculated by different models are all greater than 0.97, with the first-order chemical reaction model (O1) demonstrating the highest goodness-of-fit for Pine wood (R² = 1.000) and Eucalyptus wood (R² = 0.995), indicating that homogeneous chemical reactions dominate the combustion process. The initial combustion temperatures of China fir, Eucalyptus wood, and Pine wood are 256 °C, 262 °C, and 270.9 °C, respectively, with flammability indices of 1.08, 1.46, and 1.15 and comprehensive combustion characteristic indices of 2.71 × 10⁻², 1.26 × 10⁻², and 1.75 × 10⁻² °C⁻²min⁻¹, respectively. This work provides important theoretical support for both the energy utilization of timber-framed buildings waste and the fire protection design and flame retardancy of timber-framed buildings, contributing to the development of scientific fire prevention measures and the preservation of this architectural heritage. Full article

Hexavalent chromium (Cr(VI)) contamination in water bodies poses severe risks to ecosystems and human health due to its high solubility, mobility, toxicity, and carcinogenicity. Conventional treatment methods are often limited by high costs, secondary pollution, and inefficiency at scale. This review critically evaluates biochar (BC) as a sustainable solution for Cr(VI) removal from aqueous environments, with a specific focus on comparing the efficiency of pristine BC with that of modified BCs, including non-noble metal/BC, heteroatom/BC, and non-noble metal–heteroatom/BC. It summarizes the fundamental chemistry of Cr(VI) in aqueous environments, particularly pH- and redox-dependent speciation, bioavailability, and toxicity. Pristine BC removes Cr(VI) through electrostatic attraction, reduction to trivalent chromium (Cr(III)), surface complexation, and physisorption; however, it suffers from limited efficiency, poor surface functionality, and weak redox activity. Modification strategies overcome these limitations; for instance, iron-modified BC (Fe/BC) introduces magnetic properties, abundant reactive sites, and efficient Cr(VI) reduction, while nitrogen-doped BC (N/BC) enriches surface functional groups and improves electron transfer; Fe and N co-doped BC (Fe-N/BC) synergistically combines both advantages, achieving higher Cr(VI) removal capacities, far exceeding those of pristine BC. Characterization (SEM, FTIR, and XPS) and modelling (adsorption isotherms and kinetics and density functional theory calculations) techniques confirm the dominant chemisorption and reduction mechanisms of modified BCs. Despite promising laboratory-scale results, challenges remain in field-scale validation, long-term stability of immobilized Cr(III), nanoparticle leaching, and competitive adsorption, which are added in this review as future research directions via integration with machine learning and modelling approaches. Full article

The structural safety of a marine remotely operated vehicle (ROV) launch and recovery system (LARS) under extreme sea conditions determines the reliability of underwater exploration. To address the susceptibility of traditional rigid frames to local yielding and dynamic instability under transient high-frequency impacts from a mother ship, this study conducts structural dynamics simulation and vibration reduction optimization for a heavy-duty ROV LARS. A spatial finite element model was established, introducing boundary conditions that decouple the static gravity field from the transient inertial mass. Mechanical responses under eight typical operating conditions were systematically evaluated. Results indicate that the rigid frame experiences significant limitations under a 1 g horizontal transient impact, with peak stress reaching 195.38 MPa and deformation exceeding 20 mm. Consequently, a non-invasive vibration reduction strategy using viscoelastic damping boundaries is proposed, alongside an equivalent buffer dynamics model. Verifications demonstrate that this flexible damping constraint prolongs collision momentum transfer time and dissipates impact kinetic energy. Post-optimization, maximum transverse and longitudinal von Mises stresses decrease by over 37%, and transient deformation is reduced by over 64%. This study addresses the weight penalty of traditional strengthening designs, providing a mechanical reference for the lightweight design and impact protection of heavy-duty marine equipment. Full article

Food industry wastewater containing synthetic dyes threatens ecological safety and human health. Therefore, efficient and environmentally friendly adsorbents that can remove synthetic food dyes from wastewater are urgently needed. In this work, a self-nitrogen-doped biochar (GSNBC), used for adsorption of food dyes including carmine and tartrazine, was facilely prepared by employing ginger straw waste as the carbon precursor and NaHCO₃ as a mild and relatively benign pore-forming agent via one-step pyrolysis. The as-prepared GSNBC featured well-developed porous structures, a specific surface area of 1712.52 m² g⁻¹, and rich oxygen- and nitrogen-containing functional surface groups. Particularly, GSNBC performed ultrafast adsorption, with approximately 90% of the equilibrium capacity within 1 min (600.13 mg g⁻¹ and 580.24 mg g⁻¹ for carmine and tartrazine, respectively), and reached adsorption equilibrium at about 10 min. In addition, it exhibited excellent regenerability. The adsorption kinetics and isotherms fit well with pseudo-second-order and Langmuir models. DFT calculations indicated that π–π stacking and hydrogen bonding were mainly responsible for the adsorption. This study presents not only a promising and efficient adsorbent for the remediation of dye-laden food industry wastewater but also a sustainable route for the resource utilization of ginger straw waste. Full article

This study investigated the effect of replacing N₂ with CO₂ on the pyrolysis behavior, char structure evolution, and kinetics of Fushun (FS) and Changji (CJ) oil shales. Non-isothermal thermogravimetric experiments were conducted at 5, 10, 20, and 40 °C·min⁻¹ under N₂ and CO₂ atmospheres, and the resulting chars were characterized by FTIR, XPS, BET, and SEM. Kinetic parameters were evaluated using Friedman, FWO, KAS, Starink, and Vyazovkin iso-conversional methods. Both oil shales underwent three stages: moisture release, main organic-matter pyrolysis, and high-temperature mineral decomposition. Increasing the heating rate shifted T_s and T_max to higher temperatures and intensified volatile release. At 40 °C·min⁻¹, replacing N₂ with CO₂ increased T_s from 322.6 to 399.3 °C for FS and from 368.1 to 377.3 °C for CJ, while reducing the maximum mass-loss rates to 6.81 and 8.66%·min⁻¹, respectively. N₂ favored pore development, increasing the specific surface areas of FS and CJ chars to 14.1402 and 6.1464 m²·g⁻¹, whereas CO₂ caused pore blockage in FS char and reduced its surface area to 2.7783 m²·g⁻¹. XPS showed that CO₂ promoted the formation or preservation of oxygen-containing surface carbon, especially C=O and O–C=O groups. The E_α values first decreased and then increased with conversion and were generally lower in CO₂ than in N₂. The average activation-energy differences between the two atmospheres were 23.5 and 43.2 kJ·mol⁻¹ for FS and CJ, respectively. These results provide experimental and kinetic data for modeling primary oil shale pyrolysis and subsequent char combustion and gasification under CO₂-rich conditions. Full article

A nickel oxide/attapulgite (A-ATP/NiO) nanocomposite was synthesized and evaluated for the adsorption and Fenton-like degradation of Rhodamine B (Rh-B) in an aqueous solution. The composite was characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and Brunauer-Emmett-Teller (BET), confirming the successful immobilization of NiO nanoparticles into the attapulgite framework. The attapulgite modification results in enhanced surface properties, including increased surface area (from 68.9 to 111.3 m² g⁻¹), pore volume, and the availability of active sites. Batch experiments demonstrated a high affinity of A-ATP/NiO toward Rh-B, achieving 52% adsorption within 60 min. Upon addition of Fenton reagent (H₂O₂), the composite exhibited excellent catalytic performance, achieving 97% Rh-B degradation in 10 min and almost complete removal (99.39%) within 60 min under optimized conditions (pH 3, 303 K, H₂O₂ 5 mmol L⁻¹, catalyst dose 0.03 g L⁻¹, dye concentration 50 ppm). The synergistic combination of adsorption and catalytic oxidation significantly enhanced dye removal, with reactive hydroxyl radicals (•OH) driving the degradation process. Kinetic analysis indicated that the removal followed a pseudo-first-order model, suggesting that physisorption and surface diffusion are the primary mechanisms for Rh-B degradation. These findings highlight A-ATP/NiO as a low-cost, environmentally friendly, and highly efficient material for the rapid and sustainable remediation of Rh-B-contaminated wastewater. Full article

Agro-industrial residues from livestock and sugarcane production—particularly abundant in regions such as Veracruz, Mexico, where both agro-industries co-occur in high density—constitute underutilized carbon and nitrogen streams with high potential for biotransformation within circular bioeconomy frameworks. This study aimed to evaluate whether inoculation with Lactobacillus delbrueckii subsp. bulgaricus SP96 at increasing levels (5, 10, and 15% v/v) achieves simultaneous stabilization, carbohydrate-to-lactic-acid conversion, and nutritional enrichment of a thermally pretreated bovine manure (BM)–agro-sugarcane waste (ASCW) mixture, and to describe the underlying growth kinetics using the Gompertz model. Thermal pretreatment reduced Salmonella spp. and fecal coliforms to levels compliant with NOM-004-SEMARNAT-2002 Class B biosolid standards, yielding a substrate with suitable fermentability (14.56 gL⁻¹ carbohydrates, 0.44% total nitrogen, pH 6.52, and 90.43% volatile solids). Fermentation at 37 °C and 120 rpm for 72 h followed Gompertz kinetics (R² = 0.92–0.97). The 15% inoculum achieved the highest conversion efficiency and product yield (lactic acid and carbohydrate consumption), whereas the 10% inoculum represented the most balanced operating condition (best kinetic fit, R² = 0.97). However, differences in lactic acid concentration among treatments were not statistically significant (p > 0.05). The resulting biomass showed high organic matter (93.45%), increased crude protein (8.5%), a C/N ratio of 39.9, and enrichment in P₂O₅, MgO, Na₂O, and B. These findings validate a low-cost, scalable platform for simultaneous waste stabilization and generation of value-added, protein-enriched biomass with potential application as a feed supplement and soil amendment, pending further safety and functional characterization, from agro-livestock residues. Full article

This study examined total phenolic release and mass transfer during sequential pyruvic acid (PA) pretreatment and sodium hydroxide (NaOH) extraction of bamboo leaves. A 4 × 4 design comprised PA concentrations of 7.0, 8.0, 9.0, and 10.0% and NaOH concentrations of 3.0, 4.0, 5.0, and 6.0%. Kinetic curves from 40 to 120 min showed rapid release followed by a gradual approach to equilibrium. Normalized conversion F(t) was used to evaluate release progression, and two consistent fitting windows were applied for parameter estimation. The LDF model described the 40, 60, and 80 min data and provided k_f, while the Crank spherical diffusion model described the 80, 100, and 120 min data and provided D_eff. These overlapping windows represent different portions of the same continuous extraction process rather than physically separate stages. Model comparison and predictive validation supported the framework. The characteristic time ratio τ_m/τ_d exceeded 2 under all tested conditions, indicating that external liquid film transfer contributed the greater relative resistance. The condition of 8.0% PA and 5.0% NaOH provided the most balanced performance, yielding 18.55 ± 0.26 mg GAE/g, equivalent to 94.4% of the maximum. These results provide a practical basis for rate control analysis and condition selection. Full article

Periodontitis, a chronic inflammatory disease driven by plaque biofilm, is a leading cause of tooth loss in adults worldwide. Effective treatment requires not only infection and inflammation control but, more critically, functional regeneration of the periodontal ligament, cementum, and alveolar bone. Periodontal regeneration, however, is a highly ordered, multi-stage biological cascade involving temporally coordinated phases of blood clot formation, inflammatory regulation, tissue formation, and remodeling. Conventional single-drug or mixed-delivery strategies cannot distinguish the distinct demands of each healing phase and fail to replicate this natural rhythm. Sequential controlled-release systems address this gap by delivering multiple bioactive agents (antimicrobials, immunomodulators, and growth factors) in a programmed order tailored to the healing cascade, enabling precise modulation of the periodontal microenvironment and orderly tissue regeneration. This review systematically summarizes advances in these systems, classifying material platforms into four categories: (1) diffusion-barrier and degradation-kinetics systems, including multilayer films, core–shell fibers, porous microspheres, and microneedle arrays; (2) stimuli-responsive systems triggered by pH, matrix metalloproteinases, reactive oxygen species, or exogenous physical stimuli; (3) cell and extracellular vesicle-based systems exploiting the inflammatory tropism of M2 macrophage-derived exosomes for targeted immune reprogramming; and (4) asymmetric structural designs achieving spatiotemporal coordination of physical and biochemical signals through hierarchical architectures. These systems follow an anti-infection/anti-inflammation first, osteogenesis later therapeutic logic, circumventing temporal antagonism among bioactive factors. However, significant challenges hinder clinical translation, including individualized prediction of release kinetics, long-term biocompatibility of carrier materials, material retention under dynamic oral conditions, translational limitations of animal models, and precise regulation of complex factor networks. Future progress will likely depend on multi-responsive and logic-gated systems, deeper integration of biotechnology and immunomodulation, personalized precision medicine, AI-driven material design, and robust clinical translational research. Full article

Aim: To establish and validate a quantitative transporter-mediated imaging framework based on gadoxetic acid-enhanced T1 mapping for assessing liver functional reserve (LFR) and to investigate the physiological significance of the relative change in longitudinal relaxation rate (ΔR1%) as a quantitative imaging biomarker. Methods: Female C57BL/6J mice (6–8 weeks old) representing five experimental liver conditions (control, transporter-deficient Slco1b2/Slco1a5 double-knockout, carbon tetrachloride-induced fibrosis, methionine–choline-deficient diet-induced steatohepatitis, and alcohol-associated fatty liver disease; n = 6 per group) underwent serial Gd-EOB-DTPA-enhanced T1 mapping. Quantitative ΔR1% was calculated to characterize hepatobiliary enhancement kinetics. Liver functional reserve was independently evaluated using multispectral optoacoustic tomography of indocyanine green (ICG) pharmacokinetics and serum ICG retention assays, with histopathological and hepatocellular transporter analyses performed for mechanistic validation. Longitudinal data were analyzed using restricted maximum likelihood (REML)-based mixed-effects models. Intergroup comparisons were performed using one-way ANOVA or Kruskal–Wallis tests with appropriate post hoc analyses, and associations between imaging and functional parameters were evaluated using Spearman rank correlation analysis. A two-sided p < 0.05 was considered statistically significant. Results: Five experimental liver models exhibited distinct transporter-dependent hepatobiliary enhancement patterns. The transporter-deficient knockout mice showed minimal enhancement, whereas fibrosis and steatotic liver injury models demonstrated intermediate but clearly distinguishable functional profiles. Longitudinal mixed-effects analysis identified significant effects of time, experimental group, and time-by-group interaction on ΔR1% dynamics (all p < 0.0001). Although MRI-derived ΔR1% parameters were not significantly correlated with regional optoacoustic ICG kinetics, ΔR1% area under the curve showed a strong inverse correlation with serum ICG retention at 600 s (r = −0.729, p < 0.0001), indicating that MRI-derived ΔR1% and ICG-based measurements provide complementary rather than interchangeable assessments of liver function. Histological and molecular analyses further demonstrated marked heterogeneity in fibrosis, steatosis, and hepatobiliary transporter expression across models, whereas transporter abundance alone did not consistently predict imaging-derived functional performance. Conclusions: Quantitative Gd-EOB-DTPA-enhanced T1 mapping provides a transporter-mediated imaging framework for evaluating hepatic functional reserve across mechanistically distinct liver injury models. As a normalized quantitative imaging biomarker, ΔR1% captures the integrated functional consequences of hepatobiliary transport dysfunction and complements established liver function tests. These findings support the translational potential of quantitative T1 mapping as a standardized, noninvasive approach for assessing liver functional reserve. Full article

Bioactive collagen peptides and collagen hydrolysates are dietary proteins whose degradation products also carry signaling activity. This second part of a two-part narrative review addresses the translational dimensions of their bioactivity, integrating veterinary clinical trials, controlled animal-model studies, and human biomedical data, with evidence strictly stratified by type. The gastrointestinal tract acts not only as the absorption site but as a target organ. In cell culture and rodent models, luminal collagen fragments restore tight-junction integrity, alter the microbiome, and shift the enterohepatic bile acid pool; increased secondary bile acid synthesis is proposed to engage the farnesoid X receptor (FXR) and Takeda G-protein-coupled receptor 5 (TGR5). None of these steps have been demonstrated in veterinary clinical patients. The accompanying GLP-1 and PYY response may reflect direct amino acid stimulation of enteroendocrine cells as much as a bile acid-dependent route, and current data do not separate the two. Veterinary trials show objective kinetic improvement in osteoarthritic dogs and horses. Taurine-responsive dilated cardiomyopathy is a reversible, diet-amenable condition; as the principal bile acid conjugation substrate in carnivores, taurine acts on the same bile acid pool as a mechanistically separate input. Recent data implicate prolyl-hydroxyproline in brown adipogenesis, collagen peptides in hippocampal neurogenesis, and taurine in platelet normalisation. The gut–collagen peptide axis is an evolving model linking dietary collagen to systemic metabolic, endocrine, and immune signaling, with implications for companion-animal, equine, and livestock practice. Full article

Cr(VI) is considered one of the most dangerous pollutants due to its bioaccumulation and toxicity, which has driven the search for sustainable and effective solutions for its removal from wastewater. In this regard, the aim of this research was to develop a material based on cellulose acetate (CA) extracted from Cocos nucifera L. fibres and polyhydroxybutyrate (PHB) for the removal of Cr(VI). The biocomposite (PHB/CA) was synthesised using the casting method; its adsorption capacity was evaluated in batch systems and its efficiency measured at different contaminant concentrations. The characterisation results indicated interactions between the fibres and the PHB, resulting in a porous material containing hydroxyl, amino, ether/alcohol, carbonyl and alkane/alkyl functional groups. Cr(VI) removal tests indicated that the optimal operating conditions were achieved at a pH of 3 and a concentration of 15 mg/L, yielding an adsorption efficiency of 44.5%, and showing a trend consistent with the Elovich kinetic model and the Langmuir isotherm. In conclusion, this research proposes the exploration of new bioadsorbents derived from coconut agro-industrial waste combined with biopolymers for the remediation of contaminated water, thereby expanding our understanding of the relationship between the structure of bio-composites of renewable origin and their performance in heavy metal adsorption processes. Full article

As exploration expands into deep and unconventional petroleum systems, light oil and condensate have become key targets for reserve growth and production enhancement. This study employs the gold tube pyrolysis of kerogens from Cretaceous Qingshankou shale to investigate the role of hydrocarbon (HC) expulsion in light oil and condensate generation during thermal maturation. The results show that HC expulsion significantly reduces overall HC yields and alters their chemical composition. Specifically, compared with immature kerogen, n-hexane-extracted mature kerogen (EasyR_o = 0.96%) exhibited reductions of 60%, 57%, and 50% in C₁₅₊ compounds, C_6–14 HCs, and C_1–5 gases, respectively. Moreover, the generation window of C_6–14 HCs (a proxy for light oil) is narrowed and shifted toward lower maturity. Kinetic parameters were further used to establish two separate evolutionary models for methane, wet gas, light oil, and heavy oil. Based on these models, the shale oil resource potential of the first member of the Qingshankou Formation, the Qijia–Gulong Sag, is estimated to be (6.95–8.80) × 10⁶ ton/km² for the no-HC-expulsion scenario and (3.63–3.85) × 10⁶ ton/km² for the significant-HC-expulsion scenario (HEE = 84.35%). These results provide a valuable reference for assessing the light oil and condensate potential of high-maturity Qingshankou shale in the Songliao Basin. Full article