Search Results (358)

To investigate the effect of Botrytis cinerea infection severity on the flavor characteristics of Petit Manseng noble rot wine, this study analyzed wines produced from Petit Manseng grapes grown in the eastern foothills of Helan Mountain, Ningxia, China. The grapes were categorized into three groups based on infection status: uninfected, mildly infected, and severely infected with Botrytis cinerea. Headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS) and an electronic nose were employed to detect and analyze the aroma components of wines under the three infection conditions. Additionally, trained sensory panelists conducted sensory evaluations of the wine aromas. The results revealed that wines made from severely infected grapes exhibited the richest and most complex aroma profiles. A total of 70 volatile compounds were identified, comprising 32 esters, 17 alcohols, 5 acids, 8 aldehydes and ketones, 4 terpenes, and 4 other compounds. Among these, esters and alcohols accounted for the highest contents. Key aroma-active compounds included isoamyl acetate, ethyl decanoate, phenethyl acetate, ethyl laurate, hexanoic acid, linalool, decanoic acid, citronellol, ethyl hexanoate, and methyl octanoate. Sensory evaluation indicated that the “floral aroma”, “pineapple/banana aroma”, “honey aroma”, and “overall aroma intensity” were most pronounced in the severely infected group. These findings provide theoretical support for the harvesting of severely Botrytis cinerea-infected Petit Manseng grapes and the production of high-quality noble rot wine in this region. Full article

Objective: This study aimed to evaluate the in vitro efficacy of silver nanoparticles (AgNPs) synthesized by bioreduction using lemongrass (Cymbopogon citratus) essential oil against multidrug-resistant (MDR) bacteria isolated from an Intensive Care Unit (ICU). Methods: The essential oil was extracted and characterized by gas chromatography–mass spectrometry (GC-MS). Antioxidant activity was assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, the 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay, and total phenolic content. AgNPs (3 mM and 6 mM silver nitrate) were characterized by UV-Vis spectroscopy, dynamic light scattering (DLS), zeta potential, transmission electron microscopy (TEM), and Fourier-transform infrared (FTIR) spectroscopy. Bacterial isolates were obtained from ICU surfaces and personal protective equipment (PPE). Results: The essential oil presented citral A, citral B, and β-myrcene as major components (97.5% of identified compounds). AgNPs at 3 mM showed smaller size (87 nm), lower Polydispersity Index (0.14), and higher colloidal stability (−23 mV). The 6 mM formulation (147 nm; PDI 0.91; −10 mV) was more effective against a strain of Enterococcus spp. resistant to all antibiotics tested. FTIR analysis indicated the presence of O–H, C=O, and C–O groups involved in nanoparticle stabilization. Discussion: The higher antimicrobial efficacy of the 6 mM formulation was attributed to the greater availability of active AgNPs. Conclusions: The green synthesis of AgNPs using C. citratus essential oil proved effective against MDR bacteria and represents a sustainable and promising alternative for microbiological control in healthcare environments. Full article

The oil and gas industry is subject to significant fire hazards due to the flammability of hydrocarbons and the extreme conditions of operational facilities. Intumescent coatings (ICs) serve as a crucial passive fire protection strategy, forming an insulating char layer when exposed to heat, thereby reducing heat transfer and delaying structural failure. This review article provides an overview of recent developments in the effectiveness of ICs in mitigating fire risks, enhancing structural resilience, and reducing environmental impacts within the oil and gas industry. The literature surveyed shows that analytical techniques, such as thermogravimetric analysis, scanning electron microscopy, and large-scale fire testing, have been used to evaluate the thermal insulation performances of the coatings. The results indicate significant temperature reductions on protected steel surfaces that extend critical failure times under hydrocarbon fire conditions. Recent advancements in nano-enhanced and bio-derived ICs have also improved thermal stability and mechanical durability. Furthermore, numerical modeling based on heat transfer, mass conservation, and kinetic equations aids in optimizing formulations for real-world applications. Nevertheless, challenges remain in terms of standardizing modeling frameworks and enhancing the environmental sustainability of ICs. This review highlights the progress made and the opportunities for continuous advances and innovation in IC technologies to meet the ever-evolving challenges and complexities in oil and gas industry operations. Consequently, the need to enhance fire protection by utilizing a combination of tools improves predictive modeling and supports regulatory compliance in high-risk industrial environments. Full article

Peucedanum ostruthium (L.) W.D.J. Koch (Apiaceae) is a perennial herb native to alpine regions that is renowned in traditional medicine. This study provided a pharmacognostic evaluation, comparing the EOs obtained from its rhizomes and leaves (REO and LEO, respectively). A micromorphological analysis, which was carried out using fluorescence and scanning electron microscopy, revealed terpenoid-rich secretory ducts in both organs. The EOs were extracted by hydrodistillation and characterized by gas chromatography, coupled with flame ionization detection and mass spectrometry (GC-FID and GC-MS), revealing distinct chemical profiles. REO was dominated by monoterpenes (80.08%), especially D-limonene (29.13%), sabinene (19.77%), and α-phellandrene (12.02%), while LEO was sesquiterpene-rich (81.15%), with β-caryophyllene (21.78%), β-selinene (14.09%), and germacrene D (10.43%) as the major compounds. The in vitro assays demonstrated that both EOs exhibit significant antioxidant and anti-inflammatory activities, with LEO consistently outperforming REO across all tests. However, neither EO showed antimicrobial effects against common bacterial or fungal strains. This may have been due to the absence of polar antimicrobial constituents, such as coumarins, which are poorly recovered by hydrodistillation. To fully exploit the therapeutic potential of P. ostruthium, especially its antimicrobial properties, future studies should aim to develop integrated formulations combining volatile and non-volatile fractions, preserving the complete plant complex and broadening bioactivity. Full article

Pyrolysis is an important methodology for achieving efficient and clean utilization of coal. Lump coal pyrolysis demonstrates distinct advantages over pulverized coal processing, particularly in enhanced gas yield and superior coke quality. As a critical parameter in lump coal pyrolysis, particle size significantly influences heat transfer and mass transfer during pyrolysis, yet its governing mechanisms remain insufficiently explored. This research systematically investigates pyrolysis characteristics of the low-rank coal from Ordos, Inner Mongolia, across graded particle sizes (2–5 mm, 5–10 mm, 10–20 mm, and 20–30 mm) through pyrolysis experiments. Real-time central temperature monitoring of coal bed coupled with advanced characterization techniques—including X-ray diffraction (XRD), Raman spectroscopy, Brunauer–Emmett–Teller (BET) analysis, scanning electron microscopy (SEM), gas chromatography (GC), and GC–mass spectrometry (GC-MS)—reveals particle-size-dependent pyrolysis mechanisms. Key findings demonstrate that the larger particles enhance bed-scale convective heat transfer, accelerating temperature propagation from reactor walls to the coal center. However, excessive sizes cause significant intra-particle thermal gradients, impeding core pyrolysis. The 10–20 mm group emerges as optimal—balancing these effects to achieve uniform thermal attainment, evidenced by 20.99 vol% peak hydrogen yield and maximum char graphitization. Tar yield first demonstrates a tendency to rise and then decline, peaking at 14.66 wt.% for 5–10 mm particles. This behavior reflects competing mechanisms: enlarging particle size can improve bed permeability (reducing tar residence time and secondary reactions), but it can also inhibit volatile release and intensify thermal cracking of tar in oversized coal blocks. The BET analysis result reveals elevated specific surface area and pore volume with increasing particle size, except for the 10–20 mm group, showing abrupt porosity reduction—attributed to pore collapse caused by intense polycondensation reactions. Contrasting previous studies predominantly focused on less than 2 mm pulverized coal, this research selects large-size (from 2 mm to 30 mm) lump coal to clarify the effect of particle size on coal pyrolysis, providing critical guidance for industrial-scale lump coal pyrolysis optimization. Full article

External fields modify the confinement potential and electronic structure in a multiple quantum well system, affecting the light–matter interaction. Here, we present a theoretical study of the modulation of the nonlinear optical response simultaneously employing an intense non-resonant laser field and an electric field. Considering four occupied subbands, we focus on a GaAs/AlGaAs symmetric multiple quantum well system with five wells and six barriers. By solving the Schrödinger equation through the finite element method under the effective mass approximation, we determine the electronic structure and the nonlinear optical response using the density matrix formalism. The laser field dresses the confinement potential while the electric field breaks the inversion symmetry. The combined effect of both fields modifies the intersubband transition energies and the overlap of the wave functions. The results obtained demonstrate an active tunability of the nonlinear optical response, opening up the possibility of designing optoelectronic devices with tunable optical properties. Full article

The development of polymer binders with tailored functionalities and green manufacturing processes is highly needed for high-performance lithium–sulfur batteries. In this study, a readily hydrolyzable 3,9-divinyl-2,4,8,10-tetraoxaspiro-[5.5]-undecane is utilized to prepare a water-based binder. Specifically, the acrolein produced by hydrolysis undergoes in situ polymerization to form a linear polymer, while the other hydrolyzed product, pentaerythritol, physically crosslinks these polymer chains via hydrogen bonding, generating a network polymer (BTU). Additionally, gallic acid (GA), a substance derived from waste wood, is further introduced into BTU during slurry preparation, forming a biphenol-containing binder (BG) with a multi-hydrogen-bonded structure. This resilience and robust cathode framework effectively accommodate volumetric changes during cycling while maintaining efficient ion and electron transport pathways. Furthermore, the abundant polar groups in BG enable strong polysulfide adsorption. As a result, sulfur cathode with a high mass loading of 5.3 mg cm⁻² employing the BG (7:3) binder still retains an areal capacity of 4.7 mA h cm⁻² after 50 cycles at 0.1 C. This work presents a sustainable strategy for battery manufacturing by integrating renewable biomass-derived materials and eco-friendly aqueous processing to develop polymer binders, offering a green pathway to high-performance lithium–sulfur batteries. Full article

The evaluation of region-specific aroma characteristics in green tea remains critical for quality control. This study systematically analyzed eight Tongcheng Xiaohua tea samples (standard and premium batches) originating from four distinct regions using sensory analysis, electronic nose (E-nose), headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME-GC-MS), and chemometrics. The E-nose results demonstrated that the volatile characteristics of Tongcheng Xiaohua tea exhibit distinct geographical signatures, confirming the regional specificity of its aroma. HS-SPME-GC-MS identified 66 volatile metabolites across samples, with 18 key odorants (OAV > 1) including linalool, geraniol, (Z)-jasmone, and β-ionone driving aroma profiles. The partial least squares–discriminant analysis (PLS-DA) model, combined with variable importance in projection (VIP) scores and OAV, identified seven compounds that effectively differentiate the origins, among which α-pinene and β-cyclocitral emerged as novel markers imparting unique regional characteristics. Further comparative analysis between standard and premium grades revealed 2-methyl butanal, 3-methyl butanal, and dimethyl sulfide as main differential metabolites. Notably, the influence of geographical origin on metabolite profiles was found to be more significant than batch effects. These findings establish a robust analytical framework for origin traceability, quality standardization, and flavor optimization in tea production, providing valuable insights for the tea industry. Full article

Environmental concerns about the widespread use of non-biodegradable plastic have generated interest in developing quick and effective methods to degrade synthetic polymers. With millions of tons of plastic waste generated annually, biodegradation by microorganisms presents a promising and eco-friendly solution. However, a bottleneck has arisen due to the lack of standardized methods for verification of the biodegradation process. Based on this literature review, he techniques most commonly employed for this purpose currently include measuring mass loss, examining the surface of plastic fragments by scanning electron microscopy (SEM) and atomic force microscopy (AFM), and using analytical methods such as Fourier transform infrared spectroscopy (FTIR), pyrolysis–gas chromatography–mass spectrometry (Pyr-GC/MS) or high-performance liquid chromatography (HPLC). Each of these methods has its advantages and disadvantages. Nevertheless, currently, there is no universal approach to accurately assess the ability of individual microorganisms to degrade plastics. In this review, we summarize the latest advances in techniques for detecting biodegradation of synthetic polymers and future directions in the development of sustainable strategies for mitigating plastic pollution. Full article

The widespread presence of pesticides—especially malathion—in aquatic environments presents a major obstacle to conventional remediation strategies, while the ongoing global energy crisis underscores the urgency of developing renewable energy sources such as hydrogen. In this context, photocatalytic water splitting emerges as a promising approach, though its practical application remains limited by poor charge carrier dynamics and insufficient visible-light utilization. Herein, we report the design and evaluation of a series of TiO₂-based ternary nanocomposites comprising commercial P25 TiO₂, reduced graphene oxide (rGO), and molybdenum disulfide (MoS₂), with MoS₂ loadings ranging from 1% to 10% by weight. The photocatalysts were fabricated via a two-step method: hydrothermal integration of rGO into P25 followed by solution-phase self-assembly of exfoliated MoS₂ nanosheets. The composites were systematically characterized using X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), UV-Vis diffuse reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy. Photocatalytic activity was assessed through two key applications: the degradation of malathion (20 mg/L) under simulated solar irradiation and hydrogen evolution from water in the presence of sacrificial agents. Quantification was performed using UV-Vis spectroscopy, gas chromatography–mass spectrometry (GC-MS), and thermal conductivity detection (GC-TCD). Results showed that the integration of rGO significantly enhanced surface area and charge mobility, while MoS₂ served as an effective co-catalyst, promoting interfacial charge separation and acting as an active site for hydrogen evolution. Nearly complete malathion degradation (~100%) was achieved within two hours, and hydrogen production reached up to 6000 µmol g⁻¹ h⁻¹ under optimal MoS₂ loading. Notably, photocatalytic performance declined with higher MoS₂ content due to recombination effects. Overall, this work demonstrates the synergistic enhancement provided by rGO and MoS₂ in a stable P25-based system and underscores the viability of such ternary nanocomposites for addressing both environmental remediation and sustainable energy conversion challenges. Full article

This study aims to develop a simultaneous analytical method for detecting 19 pesticides, including 4,4′-DDD, in fishery products using gas chromatography with micro-electron capture detection (GC-μECD) and gas chromatography–tandem mass spectrometry (GC-MS/MS). A new analytical method was developed to measure pesticide residues in fishery products based on the modified Association of Official Analytical Chemists protocol combining quick, easy, cheap, effective, rugged, and safe (QuEChERS) and the Pesticide Analytical Manual for extraction and purification. Extraction was performed using acetonitrile containing 0.1% acetic acid, and purification was conducted with Florisil cartridges. The Florisil cartridges were more effective than QuEChERS in removing impurities and pigments during purification and also resulted in a reduced matrix effect. The validation followed Codex guidelines (CAC/GL 40). The limit of detection ranged from 2 to 3 ng/g, and the limit of quantification (LOQ) from 7 to 10 ng/g. Matrix-matched calibration curves exhibited linearity with coefficients of determination exceeding 0.99 for all target analytes. Accuracy was assessed based on recovery rates, while precision was evaluated using relative standard deviations (RSD) at three spiking levels (LOQ, 10×LOQ, and 50×LOQ). The recovery rates ranged from 62.6 to 119.1%, with RSDs of 0.4 to 19.5%, conforming to Codex guidelines. Full article

This study investigates the impact of using Lactiplantibacillus plantarum and Saccharomyces cerevisiae, either individually or in co-culture, on the fermentation of rose beverage. We comprehensively analyzed the resulting changes in quality characteristics and volatile compound profiles. Fermentation significantly altered the physicochemical properties, appearance, color, and free amino acid/organic acid content. Both microbial strains significantly increased total polyphenols and flavonoid content, with co-fermentation exhibiting a more pronounced effect compared to single-strain fermentations. Furthermore, the volatile compounds in rose beverages fermented with different microorganisms were characterized by an electronic nose (E-nose) and headspace–solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME/GC-MS). E-nose analysis demonstrated distinct volatile profiles distinguishing the four fermentation samples. HS-SPME/GC-MS identified a total of 245 volatile compounds, among which alcohols constituted the most abundant class. Integrating GC-MS data with odor activity value (OAV ≥ 1) analysis pinpointed 34 key aroma compounds. Partial least-squares discriminant analysis (PLS-DA) based on variable importance in projection (VIP) identified eight key volatile markers: eugenol, phenylethyl alcohol, (E)-3,7-dimethyl-2,6-octadienoic acid, methyleugenol, ethyl octanoate, citronellol, D-citronellol, and 2,4-bis(1,1-dimethylethyl)phenol. These findings provide valuable insights into the microbial influence on rose beverage quality and offer a theoretical basis for optimizing industrial fermentation processes. Full article

A novel cost-effective, rapid, and eco-friendly method was described for the removal of carbon dioxide (CO₂) from the gaseous emissions of gasoline engines. This involved the use of a sandwich filter (~10 cm diameter) made of a nonwoven poly (m-phenylene isophthalamide) (Nomex) fabric loaded with a thin layer of activated carbon. The optimized filter, with an activated carbon mass of 2.89 mg/cm², a thickness of 4.8 mm, and an air permeability of 0.5 cm³/cm²/s, was tested. A simple homemade sampling device equipped with solid-state electrochemical sensors to monitor the concentration levels of CO₂ before and after filtration of the emissions was utilized. The data were transmitted via a General Packet Radio Service (GPRS) link to an Internet of Things (IoT)-based gas monitoring system for remote management, and real-time data visualization. The proposed device achieved a 70 ± 3.4% CO₂-removal efficiency within 7 min of operation. Characterization of the filter was conducted using a high-resolution scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and Brunauer–Emmett–Teller (BET) analysis. The effects of loaded activated carbon mass, fabric type, filter porosity, gaseous removal time, and adsorption kinetics were also examined. The proposed filter displayed several advantages, including simplicity, compactness, dry design, ease of regeneration, scalability, durability, low cost, and good efficiency. Heat resistance, fire retardancy, mechanical stability, and the ability to remove other gasoline combustion products such as CO, SO_x, NO_x, VOCs, and particulates were also offered. The filtration system enabled both in situ and on-line CO₂ real-time continuous emission monitoring. Full article

Circulating fluidized bed combustion flue gas desulfurization generates large volumes of dry desulfurization ash requiring sustainable management. This study evaluated the impacts of substituting desulfurization ash for mineral powder filler in asphalt mastic on low-temperature rheological properties. Asphalt mastics were produced with 0–100% ash replacing mineral powder at 0.8–1.2 powder-binder mass ratios. Ductility and bending beam rheometer testing assessed flexibility and crack resistance. Burgers’ model fitted bending creep compliance to derive relaxation time, m(t)/S(t) index, and low-temperature compliance parameter for analytical insight. Scanning electron microscopy and Fourier transform infrared spectroscopy probed microstructural development and interaction mechanisms. Results showed that the inclusion of desulfurization ash reduced the low-temperature performance of the asphalt mastic compared to the mineral powder asphalt mastic. Additionally, as the temperature decreased further, the effect of the powder-to-gum ratio on the slurry’s crack resistance became less pronounced. Desulfurization ash primarily interacted with the base bitumen through physical means, and the performance of desulfurization ash asphalt slurry mainly depended on the degree of swelling between the desulfurization ash and the base asphalt. Full article

This study investigated the phytochemical composition and biological activities of Myrtus communis essential oil (EO) from Algeria, focusing on its antimicrobial, antifungal, and insecticidal properties using in vitro and in silico approaches. Gas chromatography–mass spectrometry (GC-MS) analysis identified myrtenyl acetate (57.58%), 1,8-cineole (17.82%), and α-terpineol (6.82%) as the major constituents. M. communis EO exhibited significant antibacterial activity, particularly against Staphylococcus aureus (13.00 ± 0.70 mm) and Salmonella typhimurium (13.00 ± 1.50 mm), with moderate inhibition of Bacillus subtilis (10 ± 1.00 mm) and Escherichia coli (9.00 ± 0.70 mm), while Pseudomonas aeruginosa showed resistance. The antifungal activity was notable against Fusarium oxysporum (16.50 ± 0.50 mm), Aspergillus fumigatus (11.00 ± 1.00 mm), and Penicillium sp. (9.00 ± 0.60 mm) but ineffective against Aspergillus niger. Insecticidal activity against Tribolium castaneum was evaluated using contact toxicity, fumigation toxicity, and repellent activity assays. The EO demonstrated potent insecticidal effects, with an LC₅₀ value of 0.029 µL/insect for contact toxicity and 162.85 µL/L air for fumigation after 96 h. Additionally, the EO exhibited strong repellent activity, achieving 99.44% repellency at a concentration of 0.23 mg/cm² after 24 h. Density functional theory (DFT) calculations provided insights into the molecular geometry and electronic properties of the key bioactive compounds. Molecular docking studies evaluated their binding affinities to bacterial enzymes (DNA gyrase, dihydrofolate reductase6, and Gyrase B) and insecticidal targets (acetylcholinesterase), revealing strong interactions, particularly for geranyl acetate and methyleugenol. These findings highlight M. communis EO as a promising natural antimicrobial and insecticidal agent, with potential applications in plant protection and biopesticide development. Full article