Diesel-methanol partially premixed combustion (DM-PPC), characterized by prior mixing and controlled autoignition, is a promising strategy for improving combustion controllability and extending methanol utilization in compression-ignition engines. However, the spatiotemporal evolution of ignition and flame development under different injection intervals remains insufficiently quantified. In this work, diesel-methanol dual-fuel direct-injection jet flame tests were conducted in a constant-volume chamber at 750 K and 40 bar. A CNNbased denoising and recognition method centered on the Fast and Flexible Denoising Network (FFDNet) was developed for jet-flame Schlieren images, integrating noise-level map generation-estimation and robust segmentation. Three DM-PPC modes were identified. In the methanol-leading low-temperature DM-PPC mode, the blue flame lasted about 0.7-0.8 ms, the yellow flame was weak and short-lived for about 0.4 ms, the flamecontour area growth-rate peak was about 2.0-3.0 m2/s, and the total flame lift-off length (FLOL) was short, about 40-80 mm, toward the methanol side. In the co-injection premixed-diffusion-coupled DM-PPC mode, multi-point ignition kernels formed within the diesel-methanol mixing zone, with flame-contour growth-rate peaks of about 7.0-9.0 m2/s and average flame-speed spikes of 170-220 m/s. In the diesel-leading diffusionflame-dominated DM-PPC mode, the short blue-flame stage was followed by strong yellow-flame clusters; the flame-contour growth-rate peak reached 1.5-1.8 m2/s, the initial average flame-speed spike increased to 200-230 m/s, and the early total FLOL was the largest, about 100 mm. The novelty of this study lies in integrating a spatially adaptive FFDNet-based denoising framework with high-speed Schlieren diagnostics to quantitatively identify injection-interval-governed DM-PPC flame modes under high-temperature and highpressure conditions.
The objective of the current study was to assess the hepatoprotective properties of nano-phytosomes (CRV-PNPs) loaded with carvacrol (CRV) in response to lead (Pb)- triggered liver injury. Male Wistar rats were assigned to six groups: Control, CRV, CRV-PNPs, Pb, Pb/CRV, and Pb/CRV-PNPs. Pb intoxication led to considerable blood profile disruption; in addition, it lowered serum total protein and its fractions. Pb also provoked an oxidative stress cascade, indicated by reductions in catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities and glutathione (GSH) levels, coinciding with a marked increase in malondialdehyde (MDA) concentrations. Pb also increased the inflammatory mediators (NF-kappa B, TNF-alpha, IL-1 beta, IL-6, NLRP3). Compared to crude CRV, CRV-PNPs provided significantly better protection against Pb-induced hepatotoxicity by restoring hematological indices and liver function, correcting dyslipidemia, and attenuating histopathological alterations. This protective efficacy was associated with improved antioxidant enzyme activity, diminished oxidative damage, and reduced inflammatory response by downregulating key mediators. Molecular docking revealed that CRV has a strong affinity for antioxidant and inflammatory proteins. The CRV-PNPs exhibited a better protective effect against Pb-induced hepatic damage than crude CRV, which might be attributed to improved stability, solubility, and bioavailability, as well as multiple protective mechanisms.
The interaction between natural gas and air in the inhomogeneous, partially premixed, stratified (IPPS) regime governs the reaction, flame structure, and combustion stability in practical systems. The mixing field in the IPPS regime exhibits local interaction between rich and lean pockets at different scales, so that the local mixing layer thickness and the mixture fraction gradient are two of the main characteristic parameters. The current investigation primarily addresses these parameters in laminar and turbulent natural gas flames within a concentric-flow conical nozzle (CFCN) burner, where mixing is well controlled across the extremes of fully premixed and non-premixed conditions. In addition, a quantitative evaluation of the level of mixture inhomogeneity has been conducted to address the details of the mixture fraction distribution for different operating parameters in laminar and turbulent combustion. Highly resolved measurements of the mixture fraction distribution at the nozzle exit of the CFCN burner were performed using the Rayleigh scattering technique. The data are illustrated in a recently developed three-axis regime diagram. A recently introduced factor representing the level of mixture fraction inhomogeneity was evaluated and used to provide a quantitative measure of the mixing field inhomogeneity for different operating conditions. The data exhibit useful correlations between the level of mixture inhomogeneity and the main operating parameters. In addition, the current study provided a strong correlation between the level of mixture inhomogeneity and the stability of IPPS turbulent natural gas flames in the CFCN burner for the first time. The stability of the IPPS flames within the CFCN burner is highest at delta MI = 0.05. The stability is then reduced at lower and higher values where the flame changes to either fully premixed or non-premixed conditions. The local mixing layer thickness and mixture fraction gradients extracted from the measurements affect the flame stability and can thus be used for quantitative analyses of the mixing field structure. The mixing layer thickness affects the interaction between the rich and lean pockets within the IPPS structure. The current study provided a useful tool for the design of a highly stabilized industrial gaseous fuel burner with a low level of pollutants.
Mosquitoes pose a significant global health threat due to their capacity to transmit fatal diseases and their growing resistance to conventional synthetic insecticides. This study synthesized and evaluated three novel 2,4thiazolidinedione (TZD) derivatives (TzTPOMe, TzTPCl, and TzTPNO2) as multi-target larvicides against the 3rd larval instar of Culex pipiens. The compounds were synthesized via Knoevenagel condensation and characterized by spectral analyses (IR, NMR, and mass) and DFT calculations at the B3LYP/6-31G(d,p) level to examine the electronic properties of their E and Z isomers. Biological evaluations demonstrated exceptional potency, with all compounds achieving up to 100% mortality at 1000 & micro;g/mL within 24 h. The nitro-substituted derivative, TzTPNO2, exhibited the highest toxicity, recording the lowest LC50 values at 24 and 48 h, respectively. Biochemical assays revealed a potent multi-target mechanism; the leading derivatives significantly inhibited neuro-enzymes (Acetylcholinesterase) and critical metabolic enzymes (GABA-T, amylase, and lipase) while simultaneously suppressing antioxidant defenses (SOD, GST, CAT, and GSH). This systemic collapse triggered catastrophic oxidative stress, evidenced by elevated lipid peroxidation and total protein carbonyl content. Safety assessments against non-target aquatic predators (Stratiomys longicornis, Cybister tripunctatus, Sphaerodema urinators, and Gambusia affinis) revealed a high selectivity toward mosquito larvae with minimal impact on predatory efficiency, supporting their environmental compatibility. These findings were robustly supported by computational modeling; molecular docking and 100 ns molecular dynamics (MD) simulations confirmed the formation of highly stable protein-ligand complexes, often exceeding the binding affinities of established inhibitors. Complemented by favorable ADMET profiling indicating high intestinal absorption and a safe, nonmutagenic profile, these TZD hybrids, particularly TzTPNO2 represent a promising strategy for developing new, resistance-breaking chemical larvicides through combined neurotoxicity, metabolic disruption, and severe oxidative damage, offering a sustainable and environmentally safe approach for integrated vector management programs.
