Search Results (307)

Real-time detection of chemical warfare agents (CWAs) and toxic industrial chemicals underpins military protection, counter-terrorism, and emergency response. Yet field instruments usually fail for a reason unrelated to sensitivity: they cannot identify agents that are not already in their reference libraries, such as novel analogs, mixtures, and degradation products. We argue that this unknown-agent problem is a structural limitation of single-modality sensing, because any one class of information (molecular bonds, ion mobility, elemental composition, or chemical reactivity) is rarely sufficient to resolve an unfamiliar threat. We review the dominant field modalities, including FTIR, Raman/SERS, ion mobility and field-asymmetric ion mobility spectrometry, laser- and spark-induced plasma spectroscopy, metal-oxide sensor arrays, and portable mass spectrometry, and show that their weaknesses are largely complementary. We then set out the principle of orthogonal multimodal sensing, in which complementary information axes are combined by machine learning with anomaly and open-set detection so that unfamiliar agents are recognized as such rather than misidentified. Four hybrid architectures are critically compared, and we examine spark-induced decomposition diagnostics, consumable-free self-decontaminating field systems with edge AI, and the open challenges of standardized datasets, calibration transfer, and validation, before outlining a roadmap toward field-relevant recognition of unidentified chemical threats. Full article

As microplastics act as ubiquitous carriers for endocrine-disrupting additives in aquatic environments, understanding their leaching dynamics is of critical concern. This study systematically investigated the effects of ultraviolet (UV) aging on the release behavior of phthalates (di-n-butyl phthalate [DnBP] and di(2-ethylhexyl) phthalate [DEHP]) from polyvinyl chloride (PVC) microplastics across diverse environmental conditions, along with the underlying mechanisms. Kinetic analyses and experimental results indicated that the release of plasticizers under UV irradiation was driven by a dynamic competition between the photochemical stability of the plasticizers and the aging of the microplastics: the apparent cumulative amount of photolabile DnBP decreased as irradiation time increased. In contrast, the release of photoresistant DEHP significantly exceeded that under dark conditions in the later stages of aging. Furthermore, highly variable environmental factors exhibited significant selectivity in regulating the release: high ionic strength inhibited plasticizer release through salting-out and cationic bridging effects, with divalent ions (Mg²⁺) in particular suppressing DEHP release by up to 96%; conversely, dissolved humic acid caused a 13-fold surge in DEHP release via robust hydrophobic solubilization. Comprehensive multitechnique characterizations (including SEM, FTIR, XRD, and XPS) confirmed that UV-induced aging—encompassing intense dehydrochlorination reactions, a marked increase in polar oxygen-containing functional groups and the amorphization of crystalline regions—fundamentally dismantled the internal mass transfer resistance, thereby creating physical pathways for the outward migration of internal plasticizers. Ultimately, this study emphasizes that the synergistic interactions between material aging and complex hydrochemical conditions must be fully integrated into assessments of long-term ecological risks and predictions of the real-world environmental fate of microplastic-associated contaminants. Full article

Lung cancer remains a leading cause of cancer-related mortality worldwide, underscoring the need for safer and more effective therapeutic strategies. In this study, zinc oxide nanoparticles (ZnO NPs) were synthesized via a green, biogenic approach using Lantana camara L. flower aqueous extract and evaluated for their anticancer potential against human non-small cell lung cancer (NSCLC) NCI-H460 cells. The biosynthesized ZnO NPs were characterized using UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), Transmission electron microscopy (TEM), energy-dispersive X-ray analysis (EDX), X-ray diffraction (XRD) and particle size analysis, confirming the formation of nanocrystalline ZnO. LC-MS profiling of the Lantana camara flower extract revealed the presence of several bioactive phytochemicals, including phenolic compounds, terpenoids, fatty acids, and alkaloids, which may contribute to the reduction and stabilization of ZnO NPs during green synthesis. Cytotoxicity assessment of ZnO NPs using MTT and trypan blue exclusion assays revealed a dose-dependent reduction in cell viability, with an IC₅₀ value of 50 µg/mL. Mechanistic investigations demonstrated that ZnO NP exposure induced significant oxidative stress, evidenced by increased nitric oxide, lipid peroxidation, and reactive oxygen species levels, along with depletion of intracellular glutathione. Apoptotic cell death was further confirmed by nuclear DNA fragmentation, mitochondrial membrane depolarization, and G0/G1 phase cell cycle arrest. Quantitative real-time PCR analysis revealed upregulation of the pro-apoptotic genes Bax and p53, accompanied by downregulation of the anti-apoptotic gene Bcl-2, indicating activation of a mitochondrial-dependent intrinsic apoptotic pathway. Collectively, these findings suggest that Lantana camara L. flower-mediated ZnO nanoparticles induced apoptotic responses associated with oxidative stress in NSCLC cells, highlighting their ability as an eco-friendly nanoplatform for further anticancer investigations. Full article

This in vitro study examined the effects of rapid high-intensity vs. conventional light-curing on real-time degree of conversion (DC) of conventional and fiber-reinforced resin composites. Two resin composites specifically designed for rapid high-intensity photo-polymerization (Tetric PowerFill, Tetric PowerFlow), two flowable fiber-reinforced composites (everX Flow, FibraFill Flow), and two condensable fiber-reinforced composites (everX Posterior, FibraFill DENTIN) were included. Photo-activation was performed using two protocols: 3 s at 3006 mW/cm² or 10 s at 1108 mW/cm². DC of 1.5 mm thick specimens (n = 6) was monitored for 5 min by real-time ATR-FTIR spectroscopy, and the maximum polymerization rate (R_DCmax) was determined. Data were analyzed using independent t-tests and ANOVA followed by Tukey’s post hoc test (α = 0.05). DC at the end of the 5 min observation period ranged from 33.7 ± 0.9% (FibraFill DENTIN, 3 s) to 59.2 ± 0.3% (Tetric PowerFlow, 10 s). All composites exhibited a significantly higher DC with the 10 s curing protocol compared with 3 s high-intensity light-curing. Within both curing protocols, Tetric PowerFlow, everX Flow, and everX Posterior achieved the highest DC values, whereas FibraFill DENTIN showed the significantly lowest DC. R_DCmax was significantly higher with the 3 s protocol than with 10 s light-curing for all materials, with the significantly highest values recorded for Tetric PowerFill and Tetric PowerFlow. FibraFill DENTIN and FibraFill Flow exhibited the significantly lowest R_DCmax for both curing protocols. In conclusion, 3 s high-intensity photo-activation increased the polymerization rate but simultaneously reduced the degree of conversion of conventional and fiber-reinforced flowable and condensable resin composites compared with a conventional 10 s light-curing regimen. Full article

The discharge of azo-dye-containing wastewater from textile and related industries represents a major environmental challenge because of the persistence, toxicity, and poor bio-degradability of synthetic dyes. Congo red dye (CR), one of the most widely used azo dyes, poses serious ecological and public health risks when released into aquatic ecosystems. Although numerous biological adsorbents have been investigated for dye removal, the development of sustainable fungal-based nanocomposites with high adsorption efficiency, optimized operational conditions, and verified environmental safety remains limited. Therefore, the present work describes the development and evaluation of a novel Aspergillus terreus–silver oxide nanoparticle (Ag₂O NPs) myco-nanocomposite as a promising eco-friendly biosorbent for CR dye removal from aqueous solutions and real wastewater. Aspergillus terreus (GenBank accession PX920301) isolated from dye-contaminated wastewater, the adsorption efficiencies of dried mycelia, and the myco-nanocomposite were compared. Myco-nanocomposite was characterized using ultraviolet visible spectroscopic analysis (UV/Vis), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). A. terreus–Ag₂O NPs myco-nanocomposite exhibited the highest ad-sorption efficiency 92.73%, adsorption capacity (qe) 118.7 mg/g and lowest CR dye residual by 3.81 mg/L, while A. terreus non-autoclaved dried mycelia recorded 78.28% CR removal, adsorption capacity (qe) 100.2 mg/g and CR dye residual by 11.39 mg/L. Adsorption parameters were optimized using a four-factor Box–Behnken experimental design, producing a highly significant quadratic model (R² = 0.986). The highest optimized conditions were obtained at run 17 in which 100 mg L⁻¹ CR dye, pH 8, 0.05 g adsorbent dosage, and 48 h contact time, with removal efficiency of 96.88%, followed by run 14 using 50 mg L⁻¹ CR dye, pH 6, 0.05 g adsorbent dosage, and 48 h contact time, with removal efficiency of 95.79%. Phytotoxicity and microbial toxicity assays demonstrated that the treated wastewater was environmentally safer than untreated CR dye, exhibiting no inhibitory effects on representative bacteria, yeast, and filamentous fungi while improving wheat seedling growth. Furthermore, application of the myco-nanocomposite to real industrial wastewater achieved 94.92% decolorization. This study provides a sustainable myco-nanocomposite of A. terreus–Ag₂O NPs which represents a promising green technology for the remediation of dye-contaminated industrial effluents and supports the development of environmentally sustainable wastewater management strategies and applicability of reusing treated wastewater. Full article

Thermal treatment of clay minerals induces a sequence of dehydration, dehydroxylation, and recrystallization reactions that control the properties of ceramic materials, calcined clays, and other high-temperature products. This review examines how vibrational spectroscopic techniques, particularly Fourier-transform infrared (FTIR), Raman, and infrared emission spectroscopy (IES), have advanced the molecular-level understanding of these transformations. Unlike conventional thermal analysis methods, these techniques directly monitor changes in hydroxyl groups, interlayer water, silicate frameworks, and newly formed phases during heating, providing real-time insight into reaction pathways and intermediate structures. The thermal behavior of major clay mineral groups, including kaolinite-group minerals, serpentines, smectites, illite, palygorskite, sepiolite, and mixed-layer clays, is compared in terms of their characteristic spectroscopic responses to increasing temperature. Particular attention is given to band shifts, intensity variations, band disappearance, and the appearance of new vibrational features associated with structural reorganization and phase development. The reviewed studies demonstrate that thermal stability is primarily governed by octahedral composition, cation–OH bond strength, vacancy distribution, and crystallinity. Integration of spectroscopic observations with complementary diffraction and thermal analysis data provides a unified framework for understanding clay mineral transformations and for optimizing thermal processing in ceramic manufacture and calcined clay applications. Full article

Directing a stream of air across the tooth when light curing resin-based composites (RBCs) may affect their degree of conversion (DC), maximum rate of polymerization (RP_max), and in vitro intrapulpal temperature. Methods: Filtek One Bulk Fill and VisCalor bulk were preheated according to the manufacturer’s instructions and used to fill a Class I cavity in a molar at 32 °C. A stream of air at either 15 or 30 psi was directed across the tooth from an air-water syringe positioned 1 cm from the buccal surface. The RBCs were light-cured for 20 s using the Bluephase N, and the DC and RP_max were determined from real-time FT-IR data. A T-type thermocouple positioned inside the pulp chamber recorded the temperature. DC and RP_max data were analyzed using one-way ANOVA, whereas temperature was analyzed using two-way ANOVA, followed by Tukey post hoc tests. Results: Directing a stream of air at the tooth produced no significant differences in the DC and RP_max. The temperature change (ΔT) decreased compared to when no air was delivered. No significant difference in ΔT was found between the two air pressures. Conclusions: Directing a stream of air across the tooth when the preheated RBC was inserted did not affect the polymerization kinetics. The air stream reduced the temperature rise inside the pulp chamber as the RBC was light-cured. Clinical Significance: Directing a stream of air across the tooth at either 15 psi or 30 psi during light curing is an easy method to reduce the temperature increase inside the pulp chamber without affecting the polymerization kinetics of the evaluated preheated RBCs in this in vitro model. Full article

Overheating of polymeric cable materials is a major contributor to insulation aging, electrical failure, and fire risk in power systems, particularly in densely installed urban underground cable corridors where heat dissipation is limited and early-stage defects are difficult to identify. Although gas-detection approaches are promising for non-invasive overheating monitoring, their practical value depends on identifying material- and lay-er-specific volatile products and clarifying how their release evolves with temperature and time. Herein, volatile products released from the PVC outer jacket of a YJV22-8.7/15 kV-3 × 185 medium-voltage cable were investigated using headspace gas chromatography–mass spectrometry (GC-MS). Temperature- and time-dependent evolution was estimated for selected marker species, and the associated degradation behavior was correlated with chemical/structural and electrical changes using ATR-FTIR, KPFM, and dielectric measurements. The number and observed headspace levels of organic components increased substantially with severe overheating, reaching more than 20 dominant components at 200 °C. 2-Ethylhexanol (2-EH) was observed across the studied range and reached approximately 300 × 10⁻⁶ (volume fraction) at 200 °C for 60 min while remaining at or below approximately 50 × 10⁻⁶ at temperatures up to 140 °C. Benzene was observed mainly at severe overheating, whereas DOTP was first observed at 140 °C among the tested conditions, reaching approximately 40 × 10⁻⁶ at 140 °C for 5 min and exceeding 300 × 10⁻⁶ under more severe conditions. KPFM showed surface roughness increasing from 7.70 to 43.39 nm, and the real permittivity increased by up to 13.9% at 50 Hz. These results provide a temperature- and time-resolved headspace dataset for the tested cable outer jacket and relate its organic-gas profile to surface and dielectric changes. Full article

This study investigates the feasibility of utilizing locally sourced Nicotiana tabacum biomass from Adıyaman, Türkiye, as a cost-effective biosorbent for the removal of copper and chemical oxygen demand (COD) from industrial wastewater originating from the Adıyaman Organized Industrial Zone. Batch adsorption experiments were conducted to systematically investigate the influence of solution pH, contact time, and initial metal concentration on adsorption performance. The untreated wastewater exhibited elevated pollution levels, with mean chemical oxygen demand and copper concentrations of 925 ± 391 mg/L and 2.54 ± 0.97 mg/L, respectively. Four tobacco-derived biosorbents (Çelikhan, Ova, Bulam, and Çağlan) were evaluated under optimized experimental conditions (pH ≈ 8.3, 60 min contact time, and a biosorbent dosage of 2.2 g/L). The Çelikhan biosorbent exhibited the highest copper removal efficiency (approximately 83%), whereas chemical oxygen demand removal ranged between 28% and 34%. The adsorption kinetics were well described by the pseudo-second-order model, with coefficients of determination ranging from 0.987 to 1.000. Isotherm analysis further indicated favorable adsorption behavior, with a maximum Langmuir adsorption capacity of 1.867 mg/g. Fourier transform infrared (FT-IR) spectroscopy confirmed the involvement of hydroxyl, carbonyl, and ester functional groups in metal binding. These findings highlight tobacco biomass as a sustainable and cost-effective biosorbent for industrial wastewater treatment. This study presents the first comprehensive evaluation of locally sourced Adıyaman tobacco biomass as a biosorbent for the removal of copper and organic pollutants from real industrial wastewater, integrating kinetic, isotherm, and FT-IR analyses to elucidate the underlying adsorption mechanisms. Full article

Against the backdrop of rapid development in low-carbon building materials, geopolymer mortar has become a high-quality alternative to traditional cement-based materials due to its advantages of environmental friendliness, high strength, and excellent durability. However, its inherent brittleness and tendency to crack severely limit its widespread adoption and use in engineering. To mitigate the inherent brittleness of geopolymer mortar, this study developed a ternary binder system composed of metakaolin, slag, and fly ash. The effects of basalt fiber contents of 0%, 0.25%, 0.50%, 0.75%, 1.00%, and 1.25% by mass on the flowability, flexural strength, compressive strength, and deformation behavior of the geopolymer mortar were systematically investigated. The evolution of the displacement and strain fields during flexural and compressive loading was monitored in real time using two-dimensional digital image correlation (2D-DIC). The fiber-reinforcement mechanism was further examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). The results show that basalt fiber reduces mortar flowability, and the reduction becomes more pronounced with increasing fiber content. The flexural strength first increased and then decreased with increasing fiber content; at 0.50% fiber content, the 28-day flexural strength reached 12.6 MPa, which was 8.2% higher than that of the fiber-free control. The compressive strength increased only slightly at a low fiber content of 0.25% and then decreased when the fiber content exceeded 0.50%. The 2D-DIC results indicate that a moderate fiber content (0.50–0.75%) markedly increased the ultimate displacement, delayed crack propagation, and enhanced the post-cracking deformation capacity. Microstructural observations revealed that an appropriate fiber content promoted good interfacial bonding with the matrix and enabled fiber bridging and crack resistance. In contrast, excessive fiber addition caused agglomeration-induced micropores and microcracks, thereby degrading mechanical properties. Overall, the recommended basalt fiber content is 0.25–0.50%. These findings provide a theoretical and experimental basis for optimizing high-performance, low-carbon geopolymer mortar for engineering applications. Full article

Background: Photodynamic therapy (PDT) is a promising minimally invasive approach for melanoma; however, many photosensitizers lose activity in aqueous media due to aggregation-induced quenching effects. Objectives: The aim of this study was to develop and characterize castor oil–based nanoemulsions containing chlorophyll (NFs-Chl) and to evaluate their in vitro photodynamic potential against melanoma cells (B16-F10), as well as their selectivity compared with human keratinocytes (HaCaT). Methods: NFs-Chl were prepared by spontaneous emulsification. Physicochemical characterization was carried out using dynamic light scattering (DLS), UV–Vis spectroscopy, FTIR, and Raman spectroscopy. In vitro assays included MTT for cell viability (IC₅₀ determination), real-time cell proliferation (RealTime-Glo™), and cell migration analysis (scratch assay). All photodynamic treatments were performed under irradiation at 660 nm. Results: NFs-Chl exhibited homogeneous nanometric sizes (≈24–31 nm) and a low polydispersity index (≈0.25–0.40), indicating a narrow size distribution. UV–Vis spectra confirmed the preservation of the characteristic absorption peaks of chlorophyll after encapsulation. In B16-F10 cells, NFs-Chl associated with PDT significantly reduced cell viability and metabolic activity over 48 h. Furthermore, NFs-Chl inhibited the migratory capacity of B16-F10 cancer cells. Cell migration assays revealed a clear inhibition of B16-F10 cell migration following treatment with NFs-Chl + PDT. Conclusions: Encapsulation of chlorophyll into castor oil nanoemulsions protected the photosensitizer, improved its cellular delivery, and enhanced its photodynamic cytotoxic effect against melanoma cells, while relatively preserving normal keratinocytes in vitro. Full article

A biogenic ZnO/Ag photoelectrode treated with atmospheric-pressure plasma was evaluated as an anode in a photo-assisted electroflotation system for the transformation of chromophoric pollutants in real industrial wastewater. ZnO was synthesized from Azadirachta indica leaf extract and plasma-treated for 10 min (M2) and 15 min (M3), with an untreated reference (M1). XRD, SEM-EDS, Raman, FTIR, EPR, and XPS analyses showed that the plasma preserved the wurtzite structure, relaxed the bulk, and modified the surface by removing residues, deoxygenating it, and activating oxygen vacancies (V_O). Although M3 reached the highest deoxygenation, M2 showed the most favorable response; thus, the performance did not depend only on the total amount of V_O. Under dark conditions, M2 showed a 14.86 percent decrease in COD compared to the control in a single batch and had the most negative ORP value. However, only ORP came close to statistical significance after multiplicity correction, with p_adj = 0.055. Under illumination, it showed the strongest photoinduced changes in conductivity and total suspended solids. The light–dark differences (ΔL−O) showed sign reversals in COD, conductivity, and pH, which identified three functional regimes and indicated that the electronic coupling of the surface V_O, rather than its amount, controlled the performance. ΔL−O was proposed as an operational test to distinguish these regimes, with the plasma exposure time as a key control variable. Because the effluent responses were single determinations, they are considered exploratory; the mechanism is primarily based on structural and spectroscopic characterization and supported by photoelectrochemical tests. Full article

The polymerization shrinkage stress (SS), degree of conversion (DC), and Vickers hardness (HV) are properties that can affect the performance of resin-based composites (RBCs). This study tested four bulk-fill RBCs used in self-cured mode: Bulk EZ Plus (Zest Dental Solutions), Cention Forte (Ivoclar), Fill-Up! (Coltene), and Stela (SDI Limited), and two light-cured bulk-fill RBCs: Filtek One (Solventum) and SDR flow+ (Dentsply). The test specimens were 6 mm in diameter and 2 mm thick. Axial SS was measured in real time for 4000 s in the self-cured materials and for 1400 s after 10 s of light curing in the light-cured materials (n = 12 for self-cured RBCs; n = 11 for light-cured RBCs). To confirm that the RBCs were adequately polymerized, the DC was assessed using real-time ATR-FTIR spectroscopy, and the HV was measured on the top and bottom surfaces using a 300-gf load for 8 s (n = 5) after 24 h. The SS, DC, and HV differed significantly among the RBCs (p < 0.001). At 1400 s, Cention Forte developed the lowest stress (1.44 MPa), whereas Bulk EZ Plus and Fill-Up! produced the highest stress (3.77 MPa). The self-cured materials continued to develop measurable stress between 1400 s and 4000 s, while the light-cured RBCs had stabilized at 1400 s. Bulk EZ Plus and Stela produced the highest DC values, and Stela had the highest HV. Full article

KTaO₃ (KTO) is a quantum paraelectric perovskite oxide which belongs to the cubic space group Pm$\overline{3}$m in a large temperature range. Polar optical modes with a T_1u symmetry of KTO are infrared-active and Raman-inactive according to the centrosymmetric exclusion principle of the selection rule. In general, the soft modes responsible for ferroelectric instability are infrared-active and Raman-inactive in the paraelectric phase. Therefore, there are still not enough studies on Raman-inactive soft modes and related phonon polaritons. In the present study, Raman-inactive polar modes and related polaritons of KTO crystals are studied by Terahertz Time-Domain spectroscopy (THz-TDS) and FTIR. The real and imaginary parts of a dielectric constant along the [100] axis are uniquely determined by transmission and reflection THz-TDS without any fitting in the low-frequency range between 6 and 225 cm⁻¹, which covers the two lowest-frequency polar modes. The reflectivity is determined by reflection FTIR in the range between 50 and 1200 cm⁻¹, and the complex dielectric constant is also estimated by the fitting in the range between 6 and 1200 cm⁻¹. The phonon–polariton dispersion relations of the real and imaginary parts of the polariton wavevector are also studied in the range between 6 and 1200 cm⁻¹. The crossover from photon-like to phonon-like polaritons and related polariton decay are observed, while no anomaly related to polariton scattering and coupling to other elementary excitations is observed in the polariton dispersion. Full article

The growing demand for sustainable smart packaging arises from the urgent need to preserve food quality and minimize environmental waste. In this study, multifunctional gelatin-based pH-responsive indicator films were fabricated by incorporating anthocyanins extracted from Hibiscus x archeri W Watson (HAE) and zinc oxide nanoparticles (ZnO-NPs). The incorporation of HAE and ZnO-NPs enhanced surface hydrophobicity, as evidenced by an increase in the water contact angle from 99° to 106°. The Fourier transform infrared (FTIR) analysis verified the lack of new chemical bond formation, indicating that the interactions among components were primarily physical in nature. Distinct colour transitions in buffer solutions of differing pH demonstrated the films’ colorimetric behavior. The films exhibited strong antimicrobial activity against Listeria monocytogenes (18.961 mm), Salmonella typhimurium (18.969 mm), and Aeromonas hydrophila (18.237 mm), whereas the neat gelatin film showed no inhibitory zone. The films also demonstrated superior UV-blocking capacity, with an opacity value (1.34 a.u/mm) compared to the control gelatin film (0.79 a.u/mm). Notably, fish fillets wrapped with the films remained fresh for up to 10 days, compared to day 4 for the unwrapped samples. These findings highlight the considerable potential of multifunctional, active and intelligent packaging for food preservation and real-time freshness monitoring. Full article