Search Results (301)

Pyrolysis of refuse-derived fuel (RDF) is a promising waste-to-energy route, but its use in higher-value applications remains limited by tar carryover, benzene, toluene, ethylbenzene, and xylenes (BTEX), heteroatom-containing compounds, and pollutant accumulation in recirculated scrubber water. This study evaluated operating windows for RDF pyrolysis coupled with direct wet scrubbing and closed-loop water reuse, with the aim of identifying regimes suitable for different end-use tiers. A Taguchi L27 design of experiments (DOE), i.e., an orthogonal array comprising 27 experimental runs, was applied to evaluate the effects of pyrolysis temperature, residence time, scrubber liquid-to-gas ratio, and scrubber-water temperature, while sequential reuse of the same scrubber-water inventory was evaluated at 5, 10, and 15 cycles. Cleaned-gas pollutants were quantified by compound-resolved gas chromatography–mass spectrometry (GC–MS) after solid-phase adsorption (SPA) sampling, while phenolics and polycyclic aromatic hydrocarbons (PAHs) in scrubber water were determined by extraction followed by GC–MS. Feasibility within each end-use tier was defined as simultaneous satisfaction of tier-specific cleaned-gas thresholds (C_tar, C_BTEX, I_N, and I_S) and the corresponding water-loop hazard limit (I_tox), using literature-informed engineering screening criteria. The results showed that stronger scrubbing reduced gas-phase tar and BTEX burdens, whereas extended water reuse caused systematic accumulation of phenolics and PAHs and increased the composite water-loop hazard index. Boiler-grade operation remained feasible across a broad operating range, with 23 of the 27 tested conditions remaining robust, whereas internal combustion engine combined heat and power (ICE-CHP) feasibility was restricted to a narrow robust regime, and no robust microturbine-grade condition was identified. These findings show that operating windows for RDF pyrolysis must be defined jointly by gas cleanliness and water-loop management constraints. Full article

The Zeta-Minimizer Theorem establishes that the Riemann zeta function $\zeta \left(s\right)$ and the primes arise variationally as unique minimizers of a phase functional defined on a symmetric measure space $\left(X,\mu ,G\right)$ equipped with helical operators. Three fundamental axioms—strict concave entropy maximization (Axiom 1), spectral Gibbs minima with non-vanishing ground states (Axiom 2), and irreducible bounded oscillations with flux conservation (Axiom 3)—allow for the selection of the non-proper Archimedean conical helix as the sole topology satisfying all constraints. Primes emerge as indivisible minimal cycles in the associated representation graph $\Gamma$ (via Hilbert irreducibility and Maschke’s theorem), while the Euler product is recovered through the spectral Dirichlet mapping of the helical eigenvalues. The partial zeta product, $Z\left(s\right)=\prod _j{\displaystyle \frac{1}{1-p_j^{-s}}},s\in \mathbb{R}\left\{0\right\},$ constitutes the exact grand partition function of any finite subsystem. Numerical inversion of this product directly recovers the mixture frequency $s$ from any experimental compressibility factor $Z_{\mathrm{m}\mathrm{i}\mathrm{x}}$. Mole fractions $x_i\left(s\right)$, interaction parameters $\Delta \left(x_i\right)$, and the Lyapunov spectrum $\lambda \left(x_i\right)$ then follow deductively via the helical transfer matrix and the closed-form linear ODE for $\Delta$. Occupation numbers $N\left(x_i\right)$ attain sharp maxima precisely at Fibonacci ratios $F_r/F_{r+1}$, leading to the molecular prime-ID rule. For twelve representative purely binary (irreducible) systems spanning atomic noble gases, simple diatomics, polar molecules, and an aromatic ring, the residuals satisfy $|Z\left(s\right)-Z_{\mathrm{m}\mathrm{i}\mathrm{x}}|<1.5\times {10}^{-8}$. The resulting $\lambda \left(x_i\right)$ curves accurately reproduce critical points, liquid ranges, and thermodynamic anomalies with zero adjustable parameters. The Riemann Hypothesis follows rigorously as a theorem: the unique fixed point of the duality functor $s\mapsto 1-s$ that preserves the orthogonality condition $\sum {\mathrm{c}\mathrm{o}\mathrm{s}}^2{\theta }^k=1$ is $\mathrm{R}\mathrm{e}\left(s\right)=1/2$, enforced by Axiom 1 concavity and Axiom 3 irreducibility. The framework is fully deductive and parameter-free and extends naturally to arbitrary mixtures and multiplicities through the helical representation graph. It provides a variational unification of analytic number theory, spectral geometry, thermodynamic phase behavior, and the Riemann Hypothesis from first principles. Full article

Sulfonated aromatic polymers (SAPs) represent promising alternatives to perfluorinated ionomers for proton-exchange membrane fuel cells (PEMFCs), but their high hydrophilicity and limited chemical stability often require structural reinforcement and controlled cross-linking. In this study, composite membranes based on sulfonated poly(phenylsulfone) (SPPSU) and sulfonated poly(ethersulfone) (SPES) were fabricated with and without electrospun PPSU nanofiber mats and subsequently cross-linked through a solvent-induced sulfone-bridge formation at 180 °C. SPPSU/SPES blends (70/30, 50/50, 30/70) displayed good miscibility, while PPSU fibers improved dimensional stability and suppressed excessive swelling. Cross-linking strongly influenced membrane properties: intermediate treatment (20 h) enhanced mechanical strength and solvent resistance with limited loss of IEC, whereas extended treatment (30 h) produced highly stable, low-swelling networks. Despite lower IEC and water uptake, 30 h-treated membranes exhibited higher proton conductivity, attributed to reduced tortuosity and more continuous ionic pathways. Mechanical and hydration analyses identified SPPSU-50, SPPSU-70, and SPPSU-100 as the most balanced compositions. Proton mobility analysis revealed high membrane tortuosity, consistent with dense cross-linked structures reinforced by fibers. Overall, the combined use of SPPSU/SPES blending, PPSU nanofiber reinforcement, and sulfone-bridge cross-linking yields robust, water-insoluble membranes with improved electrochemical performance suitable for PEMFCs and other applications. Full article

Firefighters are exposed to complex combustion products and to contaminants carried on personal protective equipment (PPE). Occupational exposure as a firefighter is classified as carcinogenic. This review summarizes the current evidence on exposure environments, routes of uptake, contamination and secondary exposure from PPE, and the effectiveness and limits of decontamination approaches. Across incident types, smoke composition varies with the fuels and combustion conditions, but fine and ultrafine particles and semi-volatile organic chemicals are common. Biomonitoring confirms uptake after incidents. Self-contained breathing apparatus reduces inhalation exposure during active suppression, yet exposures persist through dermal absorption at ensemble interfaces and post-incident tasks. Protective ensembles can retain soot-bound polycyclic aromatic hydrocarbons, additive chemicals, and metals; volatiles and particles resuspension in vehicles and stations can extend exposure. Studies show that on-scene preliminary exposure reduction and laundering can lower contaminant burdens on PPE; however, removal remains incomplete and decreases when cleaning is delayed or when gear is aged. Emerging evidence raises additional concern for per- and polyfluoroalkyl substances from foams and coating materials, with limited data on exposure metrics and removability. The field lacks standardized, realistic contamination platforms and a dose-based definition of clean PPE. Integrated intervention studies linking exposure, secondary exposure pathways, biomarkers, and decontamination methods are needed to set performance-based targets and evaluate emerging hazards. Full article

This study evaluates the feasibility of continuous indoor pollutant monitoring as an indirect method for assessing extended ventilation performance in residential buildings. This research addresses key limitations of conventional short-term tracer-gas methods, which cannot account for occupant lifestyle, environmental fluctuations, and extended ventilation variability. The study employs a diffusion-based framework to interpret pollutant-concentration equalization across the residential space over extended monitoring periods. We conducted field experiments in an apartment unit equipped with both ducted and non-ducted ventilation systems. Pollutants (PM_2.5, CO₂, HCHO, and aromatic VOCs (BTEX + styrene)) were uniformly emitted. PM_2.5 and CO₂ were continuously monitored at six spatially distributed points using calibrated sensors, while HCHO and aromatic VOCs were quantified by repeated active sampling and laboratory analysis. Under ducted ventilation, average pollutant reduction rates reached 86.8% for PM_2.5, 58.3% for CO₂, and 53.6% for HCHO. Simultaneously, spatial concentration variance decreased by up to 71% within 120 min, indicating strong diffusion-driven equalizations. These results support the feasibility of extended ventilation performance monitoring using continuous pollutant sensing, with implications for IAQ management, energy optimization, and future integration with data-driven predictive models. Full article

Water scarcity and rising fertilizer costs challenge the sustainable cultivation of medicinal and aromatic plants in arid regions. This study evaluated the interactive effects of irrigation intervals (21, 28, and 35 days) and potassium sources (potassium sulfate and feldspar) and rates on growth, yield, essential oil productivity, and nutrient status of fennel (Foeniculum vulgare Mill.) over two consecutive seasons in Middle Egypt. Extending irrigation intervals significantly increased soil electrical conductivity while reducing soil-available potassium, whereas soil pH, organic matter, and bulk density remained unaffected. Frequent irrigation (21 days) markedly enhanced vegetative growth, yield components, seed yield, and essential oil yield, producing up to 69.7 L ha⁻¹ oil compared with 50.5–52.0 L ha⁻¹ under 35-day intervals. Potassium fertilization significantly improved plant performance across all irrigation regimes, with potassium sulfate at 120 kg K₂O ha⁻¹ consistently producing the highest plant height (≈173 cm), number of umbels (≈45 plant⁻¹), 1000-seed weight (≈13 g), seed yield, and oil yield. Potassium sulfate at 120 kg K₂O ha⁻¹ consistently outperformed feldspar, though high-rate feldspar (572 kg K₂O ha⁻¹) significantly improved performance over the control, indicating potential as a supplementary source. Extending irrigation to 28 days reduced water application by approximately 23% compared to 21-day intervals, with acceptable yield levels when combined with adequate potassium supply. Potassium application enhanced seed and herb N, P, and K concentrations and mitigated the adverse effects of prolonged irrigation intervals, particularly under moderate water stress (28 days). Significant irrigation × potassium interactions confirm that optimal potassium nutrition improved water-use efficiency and reproductive performance. Overall, integrating frequent or moderately extended irrigation with an adequate potassium supply—especially soluble potassium sulfate—offers an effective strategy to sustain fennel productivity and essential oil yield under water-limited conditions. Full article

Networks of aromatic amino acid residues within microtubules, particularly those formed by tryptophan, may serve as pathways for optical information flow. Ultraviolet excitation dynamics in these networks are typically modeled with effective non-Hermitian Hamiltonians. By extending this approach to a Lindblad master equation that incorporates explicit site geometries and dipole orientations, we track how correlations are generated, routed, and dissipated, while capturing both energy dissipation and information propagation among coupled chromophores. We compare localized injections, fully delocalized preparations, and eigenmode-based initial states. To quantify the emerging quantum-informational structure, we evaluate the $L_1$ norm of coherence, the correlated coherence, and the logarithmic negativity within and between selected chromophore sub-networks. The results reveal a strong dependence of both the direction and persistence of information flow on the type of initial preparation. Superradiant components drive the rapid export of correlations to the environment, whereas subradiant components retain them and slow their leakage. Embedding single tubulin units into larger dimers and spirals reshapes pairwise correlation maps and enables site-selective routing. Scaling to larger ordered lattices strengthens both export and retention channels, whereas static energetic and structural disorder suppresses long-range transport and reduces overall correlation transfer. These findings provide a Lindbladian picture of information flow in cytoskeletal chromophore networks and identify structural and dynamical conditions that transiently preserve nonclassical correlations in microtubules. Full article

Integrating waste materials into road infrastructure is essential for environmental sustainability and resource efficiency. This study addresses the modification of short-term-aged 50/70-penetration-grade bitumen using two sustainable additives: waste toner powder and lignin. Waste toner was added at weight percentages of 4%, 8%, 12%, and 16%, while lignin was added at 15% and 20%. Since these modifiers have individual uses, this study examines how they may strengthen the oxidized binder. It focuses on extending the lifespan of the mixture by combining industrial and bio-based polymers. The main aim was to delineate the impact of these modifiers on the physical consistency, low-temperature flexibility, and microstructural morphology of the binder. The results show that both modifiers increase binder stiffness by reducing penetration at all modification rates. The resins in the waste toner enhance the polymer matrix, and the lignin’s aromatic structure increases the elastic components, improving high-temperature stability. However, ductility tests showed a reduction in elongation capability, suggesting a brittle state at lower temperatures. Also, waste toner additive is identified as the ideal modifier for high-temperature applications. SEM analysis illuminated the mechanisms underlying these performance modifications. Both additives had homogeneous distribution and good bitumen matrix interfacial bonding at lower concentrations. Full article

The interaction between small organic molecules and coal macerals plays a critical role in regulating fluid retention and transport in coal-related energy and environmental systems. However, the microscopic mechanisms governing adsorption selectivity and interfacial dynamics on different maceral surfaces remain insufficiently understood. In this study, molecular dynamics simulations were employed to investigate the adsorption and desorption behaviors of toluene (TOL) and tetrahydrofuran-2-ol (FUR) on inertinite (INE) and vitrinite (VIT) surfaces at the molecular level. Time-dependent variations in adsorption number, residence time, molecular mobility, interaction energies, and hydrogen-bond characteristics were systematically analyzed. The results reveal strong maceral- and molecule-dependent adsorption preferences. TOL exhibits the most stable adsorption on the INE surface, characterized by rapid surface accumulation, minimal desorption, and a long residence time of 0.43547 ns, which is mainly driven by strong van der Waals interactions and aromatic stacking effects. In contrast, TOL adsorption on VIT is highly dynamic, with frequent desorption events and a markedly reduced residence time of 0.1077 ns. FUR shows relatively weaker and more reversible adsorption on INE, accompanied by enhanced molecular mobility and a shorter residence time of 0.31354 ns. Notably, FUR demonstrates stronger surface retention on VIT, with an extended residence time of 0.34439 ns, which can be attributed to increased electrostatic contributions and intermittent hydrogen bonding. Hydrogen-bond analysis indicates that FUR forms longer-lived hydrogen bonds with VIT (22.05 ps) than with INE (17.86 ps), providing additional stabilization at the interface. These findings elucidate the distinct adsorption mechanisms of aromatic and polar molecules on heterogeneous coal macerals and offer molecular-scale insights into organic matter–coal interfacial processes relevant to energy extraction and subsurface transport. Full article

Fine particulate matter (PM2.5)-induced ovarian damage has attracted widespread attention, but differences in cytotoxicity and underlying mechanisms of water-soluble (WS-PM2.5) and water-insoluble (WIS-PM2.5) fractions are unclear. To investigate potential effects of PM2.5 from livestock farming environments on animal ovaries, PM2.5 samples were collected from large-scale cattle barns. There were significant differences between fractions regarding elemental composition, proportion of water-soluble ions, polycyclic aromatic hydrocarbon content, and endotoxin concentrations. Based on transcriptome sequencing results, in a cowshed PM2.5 exposure model (rats), differentially expressed ovarian mRNAs were significantly enriched in signaling pathways such as cytokine interaction and the Hippo pathway, with the expression of thioredoxin-interacting protein (Txnip) significantly increased. In vitro (primary rat ovarian granulosa cells), short-term exposure to WS-PM2.5 (12 h) significantly induced inflammatory factor release, acute oxidative stress, mitochondrial dysfunction, and intracellular Ca²⁺ overload, with characteristics of rapid acute injury. However, extended (24 h) WIS-PM2.5 exposure had greater disruptive effects on estrogen homeostasis, intracellular enzyme release (LDH), and mitochondrial structure (subacute characteristics). Furthermore, downregulating Txnip expression via inhibitors effectively mitigated cowshed PM2.5-induced ovarian granulosa cell toxicity, oxidative stress, and mitochondrial and hormonal dysfunction. In summary, solubility of cowshed PM2.5 components affected cytotoxic characteristics, and Txnip was a key factor linking oxidative stress to granulosa cell damage. The study provided a mechanistic basis and potential targets for preventing and controlling PM2.5-induced ovarian damage in livestock environments. Full article

Licorice (Glycyrrhiza glabra) is a perennial herb traditionally valued for its aromatic and therapeutic properties. In recent years, however, growing attention has shifted toward the technical and environmental potential of the plant’s industrial by-products, particularly the fibrous material left after extraction. This review integrates botanical knowledge with engineering and industrial perspectives, highlighting the role of licorice fiber in advancing sustainable innovation. The natural fiber obtained from licorice roots exhibits notable physical and mechanical qualities, including lightness, biodegradability, and compatibility with bio-based polymer matrices. These attributes make it a promising candidate for biocomposites used in green building and other sectors of the circular economy. Developing efficient recovery processes requires collaboration across disciplines, combining expertise in plant science, materials engineering, and industrial technology. The article also examines the economic and regulatory context driving the transition toward more circular and traceable production models. Increasing interest from companies, research institutions, and public bodies in valorizing licorice fiber and its derivatives is opening new market opportunities. Potential applications extend to agroindustry, eco-friendly cosmetics, bioeconomy, and sustainable construction. By linking botanical insights with innovative waste management strategies, licorice emerges as a resource capable of supporting integrated, competitive, and environmentally responsible industrial practices. Full article

The evolution of type I polyketide synthase (T1PKS) assembly lines remains poorly understood. Through systematic mining of polyene biosynthetic gene clusters, we identified a novel eurocidin biosynthetic pathway capable of producing identical compounds with divergent loading module architectures, thereby capturing an evolutionary transitional state. Biochemical analysis revealed unprecedented functional reprogramming of acyltransferase (AT) domains, shifting substrate specificity from extender units (malonyl-CoA) to starter units (acyl-CoA). This paradigm shift enables direct initiation of polyketide chain assembly via AT-mediated loading of starter units, thereby elucidating the origin of extant AT-initiated assembly lines and establishing AT functional plasticity as a novel mechanism for polyketide structural diversification. Parallel evolution of ketosynthase (KS) domains through KSS→KSQ mutations further diversified initiation strategies. Applying this evolutionary insight, we engineered the candicidin pathway by replacing its native aromatic-starting bimodule with a starter-selective monomodule from eurocidin, generating aliphatic-starting analogs. This demonstrates that evolution-inspired AT reprogramming provides a rational framework for modifying polyketide starter units, expanding structural diversity, and enhancing therapeutic potential. Full article

This study investigates the synthesis and photochemical behavior of a series of (E)-1-aryl-1,3-butadienes with different aromatic substituents. Despite their simple structure and straightforward preparation, detailed studies of their photochemical properties, especially UV light-induced (E) to (Z) isomerization, are scarce. Our results demonstrate that these compounds can efficiently undergo photo-triggered geometric changes, highlighting their potential as functional units in photochemical applications. The findings underline the significance of extended conjugation in managing excited-state processes, providing new insights into the dynamics of photoinduced transformations in conjugated diene systems. Additional computational analyses show how geometric modifications influence conformational energies in the synthesized compounds. Overall, these results improve understanding of structure–reactivity relationships and lay the foundation for designing photoresponsive materials based on (E) and (Z)-1-aryl-1,3-butadiene frameworks, with promising applications in photochemistry and materials science. Full article

Pane Toscano DOP, a traditional sourdough bread from Italy, has a limited shelf life, typically lasting only a few days. Extending its shelf life without the use of synthetic preservatives is essential to meet the rising demand for clean-label products and to reduce food waste. This study aimed to identify the most effective packaging strategy to extend the shelf life of Pane Toscano DOP. Two packaging systems were evaluated: single-package and bag-in-bag systems. In the single-package setup, bread was packaged in PET/PE under different headspace conditions: ambient air (C1), air + Everfresh^® Spray (EVF, a natural aromatic extract) (C2), CO₂ only (C3), and CO₂ + EVF (C4). In the bag-in-bag system, bread was first placed in a PLA primary package containing air and then enclosed within a PET/PE secondary package filled with either air (T1), air + EVF (T2), CO₂ only (T3), or CO₂ + EVF (T4). Shelf life of bread under different packaging conditions was evaluated based on the appearance of visible mold growth. T4 exhibited the longest shelf life, maintaining acceptable quality for 41 days, followed by T3 with 34 days. Air packaged samples C1 and T1 had the shortest shelf life of only 6 days, while C2, T2, and C3 each maintained quality for 20 days. These findings demonstrate that the use of modified atmosphere packaging, bag-in-bag systems, and aromatic headspace extracts can significantly extend the shelf life of artisanal breads, such as Pane Toscano DOP. This approach offers viable alternatives to synthetic preservatives while maintaining traditional product formulations. Full article

High-risk neuroblastoma (NB) is an aggressive pediatric tumor characterized by pronounced biological heterogeneity and frequent development of chemoresistance, which critically limits therapeutic efficacy. Identifying novel anti-NB agents remains an urgent unmet need. To address this, we designed and synthesized 17 hybrid molecules by combining natural antioxidant scaffolds (coumarin, vanillin, and isovanillin) through an acyl-hydrazone linker. Several derivatives significantly reduced the viability of MYCN-amplified NB cells (HTLA-230) and their multi-drug resistant counterpart (ER) while not affecting human keratinocytes (HaCat). Among them, compounds 5, 9 and 12 selectively inhibited HTLA and ER growth (10–25%) without affecting HaCat, accompanied by robust ROS overproduction, particularly by 9 and 12 (up to 40%). None of these compounds induced apoptosis or ferroptosis. Instead, their antiproliferative effects were associated with senescence induction and, only for compound 5, with a decrease in clonogenic potential. Moreover, to further characterize compounds 5, 9, and 12, the analysis was extended across other human neuroblastoma cell lines. In parallel, the effects of the compounds on non-malignant cell lines were assessed to obtain an indication of their selectivity toward tumor cells. Compound 17, a structural analog lacking the second aromatic ring in the ex-aldehyde portion, displayed a distinct profile with a limited anticancer activity, underscoring the importance of this structural fragment for antiproliferative efficacy. Full article