Search Results (1,965)

Roasting time strongly influences almond oil yield, flavor and oxidative stability. This study investigated almond oils obtained by pressing almond kernels roasted at 130 °C for 0, 5, 10 and 20 min, corresponding to cold-aroma, light-aroma, strong-aroma and sauce-aroma groups, respectively, by combining physicochemical analysis, fatty acid quantification, gas chromatography–ion mobility spectrometry (GC-IMS), machine learning and lipidomics. Increasing roasting time enhanced oil yield from 45.81% to 50.34%, with no further significant increase after 10 min. Stronger roasting moderately reduced the free radical level. In contrast, acid value, peroxide value and thiobarbituric acid reactive substances (TBARS) increased from 0.28 to 0.38 mg KOH/g oil, 1.20 to 1.46 meq O₂/kg oil and 0.38 to 0.46 mg malondialdehyde/kg oil, respectively, indicating limited oxidative deterioration. Fatty acid analysis showed that oleic acid remained relatively stable at 644.37–647.03 mg/g oil, whereas linoleic acid decreased significantly from 150.42 to 140.19 mg/g oil. GC-IMS detected 59 volatile signals and clearly separated the four processing groups, indicating substantial roasting-induced changes in volatile fingerprints. A positive–unlabeled (PU) learning model used 27 literature-supported aroma-active compounds as the positive class and 32 compounds without confirmed aroma-activity evidence as the unlabeled class. The model showed good cross-validated discrimination, with a mean area under the receiver operating characteristic curve (ROC-AUC) of 0.866 and a mean area under the precision–recall curve (PR-AUC) of 0.756, and prioritized eight unlabeled compounds, mainly alcohols and methional, as candidate aroma-active compounds requiring further sensory validation. Lipidomic analysis showed that accelerated oxidation caused broad lipid remodeling, with 327 differential lipids between cold-aroma oxidized and unoxidized oils, mainly involving glycerophospholipids, glycerol lipids, sphingolipids and fatty acyls. Overall, increasing roasting time improved oil recovery and promoted aroma differentiation while causing only limited initial oxidative deterioration, providing a theoretical basis for optimizing roasting conditions in industrial processing. Full article

Branch prediction errors can reduce superscalar throughput by more than the error frequency alone suggests because a single misprediction can trigger redirect, squash, refetch, refill, and window recovery, which collectively disrupt sustained instruction-level parallelism. This paper presents a quantitative framework that relates prediction accuracy to realized parallelism loss in out-of-order superscalar processors. The framework separates prediction-error frequency, effective recovery cost, and unrealized issue capacity using prediction accuracy (Acc), misprediction rate (MR), effective branch penalty in cycles per misprediction (BP), parallelism loss ratio (PLR), the ratio-based branch sensitivity factor $BSF=PLR/MR$, and the slope-based branch sensitivity factor $\mathit{S-BSF}=\mathit{\partial }PLR/\mathit{\partial }MR$. BSF measures how strongly a particular processor configuration and workload convert prediction errors into lost issue capacity, whereas S-BSF provides a more stable sensitivity estimate when MR approaches zero. The framework is evaluated using timing-detailed gem5 O3 simulations on RV64GC workloads. The evaluation includes controlled branch microbenchmarks and six GAPBS graph workloads, allowing the proposed metrics to be examined under both mechanism-isolating and complex workload conditions. Two complementary controlled sweeps are used. At a fixed processor structure, predictor family and predictor level are varied to determine whether changing the predictor strengthens or weakens the relationship between MR and IPC/PLR. At a fixed predictor configuration, issue width and an effective front-end-depth proxy are varied to measure how the microarchitecture amplifies the performance cost of the remaining prediction errors. Thus, issue width is treated as an amplification variable for branch-prediction failures rather than as an independent performance topic. At the fixed structural point, Tournament and BiMode predictors show strong monotonic MR–PLR relationships on the high-branch benchmark, with Spearman coefficients of 1.00 and 0.98, whereas the Local predictor exhibits nearly unchanged MR but materially different IPC and PLR across levels. This demonstrates that the mapping from MR to throughput depends on predictor family and configuration rather than being invariant. In the controlled structural sweep, increasing issue width from 4 to 8 raises PLR by 37.6% and BSF by 55.0% on the high-branch benchmark, even though MR remains in the same order of magnitude. On GAPBS workloads, the lowest-MR configuration is not always the highest-IPC configuration, confirming that effective branch penalty and parallelism loss must be considered together with prediction frequency. These numerical findings are conditional on the evaluated single-thread gem5 DerivO3CPU model, RV64GC binaries, predictor implementations, memory hierarchy, and workload set. They characterize predictor–microarchitecture interactions in this controlled simulation environment and should not be interpreted as universal constants for all processors or applications. Full article

Liupao tea (LPT), one of China’s representative fermented dark teas, develops its unique “red, heavy, aged, and mellow” flavor characteristics. This review provides a comprehensive update on LPT aroma, integrating analyses of volatile organic compounds (VOCs), associated microorganisms, odor-active compounds (OACs), and metabolic pathways of key odor-active compounds (KOACs). With over 2000 VOCs documented, predominated by alcohols (368), hydrocarbons (357), and ketones (351), the total for LPT substantially exceeds the approximately 1000 compounds typically reported for other dark teas. By combining sensory evaluation with techniques such as gas chromatography–olfactometry (GC-O) and odor activity value (OAV), KOACs, predominantly comprising alcohols, aldehydes, and methoxybenzene derivatives, were identified as key contributors to the floral, fruity, aged, stale and other notes that define LPT’s characteristic aroma. The formation of the aroma compounds is closely linked to microbial metabolism and the enzymatic activities generated by microorganisms. Fungi, including Aspergillus, Rhodotorula, Geosmithia, Wallemia, Penicillium, Blastobotrys, Fusarium, and Xeromyces, and bacteria, including Burkholderia, Ralstonia, and Achromobacter, serve as the primary functional microorganisms driving fermentation and aging. This review provides a comprehensive framework for understanding the chemical and microbial complexity of LPT aroma. Full article

Fuel cells (FCs) are critical for decarbonizing the transport industry, with Life Cycle Assessment (LCA) serving as the standard evaluation framework. However, existing literature exhibits severe methodological heterogeneities and divergent system boundaries that introduce deep epistemic uncertainties. This review conducts a systematic analysis to critically harmonize FC environmental performance across the road, aviation, and maritime sectors. Quantitative synthesis reveals global warming potential (GWP) as the dominant metric. For light-duty vehicles, GWP drops to around 30 gCO₂eq/km, matching battery-electric configurations exclusively under deeply decarbonized grids. Manufacturing FC stacks and advanced storage imposes a severe upfront carbon debt, particularly prominent in heavy-duty freight (60–130 tCO₂eq). In aviation, 80–90% in-flight GWP reductions trigger massive burden-shifting, transferring 60–70% of lifecycle damages to ground-based infrastructure. Maritime FCs shrink GWP to 0.06–0.60 kgCO₂eq/kWh, strictly contingent on upstream hydrogen production. Crucially, despite long-term GWP advantages, FC pathways face systematic penalties in acidification, eutrophication, and ecotoxicity, heavily driven by platinum-group catalysts and fluoropolymer membranes. By isolating software-driven biases and database discrepancies, this work delivers an actionable methodological roadmap, establishing a policy-aligned baseline for future FC transportation sustainability frameworks. Full article

Deep eutectic solvents (DESs) are promising electrolyte media for solar redox flow batteries, but their high viscosity and sluggish ion transport can limit redox-species diffusion, interfacial charge transfer, and photocharging performance. This study aimed to regulate a TEMPO/VCl₃-based DES electrolyte by controlled water addition for a Yb,Er-doped TiO₂–g-C₃N₄ photoanode solar redox flow battery. DES electrolytes containing 0, 5, 10, and 15 wt% added water were evaluated by physicochemical, electrochemical, and photoelectrochemical measurements, while full-cell tests compared pristine DES with the half-cell-selected 10 wt% electrolyte. While water incorporation systematically enhanced bulk redox-species transport, the optimal photoelectrochemical performance was achieved at 10 wt% water, rather than 15 wt%. Although the 15 wt% electrolyte exhibited the highest bulk diffusivity, the 10 wt% composition provided the most favorable balance between mass transport and interfacial charge transfer kinetics. The Raman spectra supported water-induced reorganization of the bulk DES hydrogen-bonding network. Full-cell tests confirmed that the 10 wt% water-containing electrolyte delivered higher and more stable photocharging responses than pristine DES over 20 cycles. These results indicate that moderate water regulation is an effective strategy for improving DES-based solar redox flow batteries. Full article

Quorum sensing (QS) is critically involved in mediating microbial interactions and serves as a central regulatory mechanism in bacterial pathogenesis. As an emerging countermeasure, quorum quenching (QQ) suppresses QS-regulated virulence through enzymatic or chemical disruption of signal systems. N-acyl homoserine lactone (AHL), an evolutionarily conserved QS signal, coordinates the pathogenicity of multiple plant pathogens, particularly Dickeya zeae, which causes soft rot disease in various crops and leads to substantial agricultural losses. In this study, the QQ strain Acinetobacter schindleri XJ-10 was evaluated for its capacity to degrade AHL and attenuate the pathogenicity of D. zeae EC1 in host plants. Notably, strain XJ-10 exhibited efficient AHL degradation at 0.2 mmol/L within 24 h, achieving a degradation efficiency of 98.80%. Subsequently, gas chromatography–mass spectrometry (GC-MS) analysis identified N-hexanoyl-L-homoserine lactone and propanamide as key intermediates during AHL degradation, confirming complete mineralization to CO₂ and H₂O. Based on the structural characterization of AHL and its intermediates, the metabolic pathway within strain XJ-10 was proposed. The degradation pathway initiates with the hydrolysis of the ester ring of N-hexanoyl-L-homoserine lactone, generating N-hexanoyl-L-homoserine. Subsequent carbon–nitrogen bond scission is predicted to yield N-cyclohexyl-propanamide, which is further catabolized to produce hexanamide and propanamide. Furthermore, strain XJ-10 exhibited biocontrol activity against soft rot disease affecting potato (Solanum tuberosum), radish (Raphanus sativus), and Chinese cabbage (Brassica rapa subsp. pekinensis), as its crude enzyme extract effectively reduced disease incidence and severity in planta. While strain XJ-10 showed no detectable acylase activity, it exhibited significant degradation activity against AHL, suggesting a distinct QQ mechanism. Collectively, these findings broaden the scope of QQ-based biocontrol strategies and enhance mechanistic insights into managing bacterial diseases through QS modulation. Full article

Conventional cement-based grouts used to stabilize fractured rock slopes and fill large cavities are heavy, carbon-intensive, and can impose excessive dead load on weakened rock masses. This study addresses these limitations by integrating bio-based rigid polyurethane—particularly castor oil-based polyurethane—into a slag-based geopolymer mortar, producing a lightweight, low-permeability, rock-adherent alternative grouting system. Three formulations were evaluated: unmodified geopolymer grout (GG), geopolymer grout modified with petroleum-based polyurethane (G-PUG), and geopolymer grout modified with castor oil-based polyurethane (GCO-PUG). Materials were characterized using infrared spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction, and scanning electron microscopy with energy-dispersive X-ray spectroscopy, and tested for apparent density, permeability, unconfined compressive strength, and direct shear behavior—including at the grout–limestone interface using rock sourced from El-Mokattam plateau, Cairo. Polyurethane incorporation reduced apparent density by up to 24% (from 22.15 to 16.89 kN/m³) and permeability to as low as 2.3 × 10⁻⁸ m/s, at the cost of a substantial reduction in compressive strength (from 5564 to 139 kN/m²). The castor oil-based grout also showed improved rock adhesion, with interfacial cohesion increasing by 67% relative to its standalone state. Accordingly, unmodified GG is recommended for high-load structural applications, whereas GCO-PUG provides a lightweight, low-permeability, and strongly rock-adherent alternative for filling large cavities and stabilizing slopes under moisture-sensitive and weight-critical conditions, where reducing self-weight and limiting water ingress are more important than achieving maximum compressive strength. Full article

This study investigates the performance, energy flow, efficiency, and environmental impact of a C-segment battery electric vehicle (BEV). As BEVs are increasingly considered a sustainable alternative to conventional internal combustion engine vehicles, a detailed understanding of their energy utilization and operational emissions is essential. A MATLAB/Simulink-based vehicle model incorporating an 88.5 kWh battery pack, a 160 kW permanent magnet synchronous motor (PMSM), regenerative braking, and longitudinal vehicle dynamics was developed. The developed model was validated by comparing the simulated vehicle performance characteristics with the publicly available specifications and performance data of the reference TOGG T10F vehicle. The vehicle was evaluated under the WLTP Class 3 driving cycle, while the effects of aggressive and high-speed driving conditions were further investigated using the US06 and Artemis Motorway 150 cycles. The results indicate a net vehicle energy consumption of 136.4 Wh/km and a driving range of 623 km under WLTP conditions. The PMSM achieved average efficiencies of 93.4% in traction mode and 92.7% in regenerative braking mode, while the cumulative battery-to-wheel drivetrain efficiency reached 81.5%. In addition, approximately 19.9% of the consumed energy was recovered through regenerative braking. Vehicle emissions were also assessed using different electricity generation mixes based on the rated energy consumption, including charging losses, yielding operational emissions between 27.7 and 116.0 gCO₂e/km. The findings demonstrate that the developed model provides realistic performance predictions and confirm the potential of BEVs to achieve high efficiency and substantially lower emissions than conventional passenger vehicles. Full article

Thermochemical depolymerization of polymer mixtures and composite materials is challenging due to non-additive degradation behavior and the emergence of new reaction pathways during pyrolysis. Both polytetrafluoroethylene (PTFE) and silicone rubber (SR) can depolymerize into monomers or low-molecular-weight oligomers when pyrolyzed individually, making them, in principle, suitable candidates for depolymerization-based recycling. Because they are frequently combined in technical applications and composites, their behavior during co-pyrolysis warrants investigation. However, the pyrolysis of PTFE:SR mixtures and composites remains poorly understood. In this study, we examine the pyrolysis behavior of PTFE:SR systems with emphasis on mass balance, product composition, and the formation of new species to address potential limitations for depolymerization-based recycling. Experiments were conducted on virgin PTFE and SR, defined polymer mixtures, and commercially relevant composites, including PTFE-lined silicone tubing and PTFE:SR septa. The results reveal a pronounced, non-linear dependence of product distribution on PTFE content. Product identification by GC-MS, NMR, and FTIR indicates cleavage of Si–O and Si–CH₃ bonds and the formation of fluorinated siloxanes as well as new per- and polyfluoroalkyl substances (PFAS). At low PTFE contents, liquid products are dominated by cyclic siloxanes (D_x). These findings show that depolymerization strategies developed for pure polymers cannot be directly applied to PTFE:SR composites. While systems with low PTFE content may be more amenable to depolymerization, higher PTFE fractions promote the formation of PFAS and difficult-to-valorize fluorinated silicon species. These products complicate selective monomer recovery and could pose significant challenges for the depolymerization-based recycling of PTFE-rich composites. Full article

Background/Objectives: Date seeds contain a wide range of biologically active constituents and have been associated with multiple health benefits. Our study aimed to evaluate the utility of biphasic aqueous methanol/chloroform extraction for separating diverse metabolites from powdered Malakabi Ajwa date seeds and to identify the most effective chromatographic and spectroscopic techniques for their comprehensive profiling and structural characterization. Methods: Biphasic extraction generated organic, aqueous, and insoluble phases. Proper chromatography-mass spectrometry and spectroscopy analytical tools were then utilized to profile the metabolites in the aqueous and organic phases. Results and Conclusions: In the organic phase, fatty acids and their methyl esters were identified using GC-MS and confirmed by ¹H NMR, while the absence of an O–H band in the FT-IR spectrum, together with ¹H NMR data, supported the natural esterification of these fatty acids. In the aqueous phase, UV-Vis spectroscopy and LC-MS revealed anthocyanin pigments, and LC-MS additionally detected four amino acids. HPLC was used to quantify and validate the sugar composition, and ¹H 1D and 2D NMR spectra enabled the assignment of α- and β-glucopyranose, β-fructopyranose, and sucrose signals. ³¹P NMR indicated that orthophosphate monoesters were the predominant phosphorus-containing compounds in both organic and aqueous phases. Overall, our findings show how an integrated chromatographic and spectroscopic workflow provides a robust strategy for comprehensive metabolite profiling of natural products such as Malakabi Ajwa date seeds. Full article

In semiconductor photocatalysis, the strong redox ability of a wide band gap and the broad light absorption range of a narrow band gap are a pair of irreconcilable trade-offs. By combining semiconductors with different band gap widths and band edge positions, both of these advantages can be achieved simultaneously. A ternary Cu₂O-SnO₂/g-C₃N₄ (CuSnCN) composite photocatalyst was prepared through the hydrothermal and calcination method. Structural analyses confirm the successful integration of truncated octahedral Cu₂O, spherical SnO₂, and layered g-C₃N₄, which extends the visible-light response to 650 nm. The optimized system achieves a remarkable 96.58% degradation of methyl orange (80 min, 0.2 g/L catalyst, pH = 3) through dual heterojunction synergies: p–n junctions (Cu₂O/g-C₃N₄ and SnO₂/g-C₃N₄) and Z-scheme charge transfer (SnO₂/Cu₂O), with •O₂⁻/h⁺ identified as the dominant reactive species. This work establishes a tunable heterojunction platform for the elimination of multiple pollutants through engineered radical-generation pathways. Full article

This study investigates the high-temperature pyrolysis pathways and product distribution of the battery immersion coolant HFE-7300 (C₇H₃F₁₃O) within a simulated thermal runaway environment. Using a tube furnace system combined with GC-MS analysis across a temperature range of 300–800 °C (residence time of 3 s), the thermal stability and cracking evolution were evaluated. Experimentally, HFE-7300 exhibits low initial decomposition at 400 °C with a pyrolysis rate of 5.84%, which rapidly scales up to 48.72% at 500 °C, and reaches a near-complete degradation of 98.46% at 800 °C. Qualitative product characterization identified C₂H₄, C₂F₄, C₃F₆ C₄F₈, and C₅H₃F₉O as the primary species evolved. To map the micro-scale degradation trajectories, a reaction network comprising 12 elementary pathways was constructed via density functional theory (DFT) calculations at the B3LYP/6-311+G(d,p) level. Using the TST method, we calculated the reaction rate constants for the main decomposition pathways. Analysis reveals that the C4–C5 bond scission pathway (R6) serves as the predominant initial decomposition channel, yielding C₅H₃F₉O and CF₂=CF₂ as the definitive primary products. These findings provide baseline thermodynamic data and critical safety insights for the engineering design of immersion-cooled battery thermal management systems. Full article

We have recently demonstrated that the pendant tert-butyldiphenylsilyl (TBDPS) groups in the short oligonucleotides TBDPS-5′-CG-3′-3′-GC-5′-TBDPS and TBDPS-5′-CGG-3′-3′-GGC-5′-TBDPS promoted the formation of new lipophilic and stable tetramolecular G-quadruplexes (GQs). Encouraged by these findings, we sought to investigate the effect of alternative lipophilic substituents at the flanking cytidine residues on GQ formation and properties. Herein, we reported on the synthesis and spectroscopic characterization of the new N⁴-benzoyl-N³-benzyl-2′-deoxycytidine, which was obtained during our attempts to synthesize N⁴-benzoyl-5′-O-benzyl-2′-deoxycytidine. Full article

Background: Bonding to sclerotic dentin remains one of the most challenging procedures in restorative dentistry due to tubular occlusion and hypermineralization, which limit resin infiltration. This study evaluated the influence of adhesive system, surface treatment, storage time, and substrate position on microtensile bond strength (µTBS) to natural sclerotic dentin. Methods: Sixteen extracted human molars with sclerotic dentin were selected and randomly assigned to nine experimental groups according to the adhesive system and surface treatment. Three adhesives were tested: a two-step self-etch adhesive (Clearfil SE Bond 2, Kuraray Noritake Dental, Tokyo, Japan) and two universal adhesives, one containing 10-MDP (G-Premio Bond, GC Corp., Tokyo, Japan) and one without 10-MDP (iBond Universal, Kulzer GmbH, Hanau, Germany). Each adhesive was applied under three conditions: no pretreatment (control), Al₂O₃ air-abrasion, and Bioglass 45S5 (ProSylc^®, Velopex International, London, UK) air-abrasion. Composite build-ups were performed, and the specimens were sectioned into 1 mm² beams for microtensile testing either after 24 h or after 6 months of storage in distilled water at 37 °C of hypertonic solution. The effect of beam position (central vs. peripheral) was also analyzed. Bond strength was measured by µTBS testing, and the results were analyzed using multifactorial ANOVA and Tukey’s test (α = 0.05). Failure modes were examined under stereomicroscopy, whereas optical microscopy was used for qualitative evaluation of representative fractured interfaces. Results: Significant main effects were found for adhesive system and surface treatment (p < 0.001), with a notable interaction between them (p < 0.05). Al₂O₃ air-abrasion produced the highest bond strengths, particularly for the self-etch adhesive containing functional monomers (53.4 ± 6.1 MPa), representing a 53% increase over the untreated control. Bioglass air-abrasion did not enhance adhesion and led to irregular hybrid layers. The position of the beams affected only one universal adhesive, with higher µTBS in peripheral regions. After six months of water storage, bond strengths remained stable across most groups, indicating good hydrolytic resistance of the interfaces. Conclusions: Both the adhesive system and the surface treatment significantly influenced bonding effectiveness to sclerotic dentin. The combination of Al₂O₃ air-abrasion with an MDP-containing self-etch adhesive achieved the most durable and homogeneous bond interface. providing a clinically reliable protocol for restorative treatments in sclerotic dentin. Within the limitations of this in vitro study, this combination may represent a potentially useful strategy for improving adhesion to sclerotic dentin, although further investigations are required to confirm its clinical applicability. Full article

Paraffin wax precipitation and deposition significantly hinder crude oil production and transportation by reducing flow efficiency, increasing operational downtime, and requiring costly remediation procedures. Conventional wax mitigation methods commonly rely on environmentally unfriendly chemicals and energy-intensive thermal or mechanical treatments. This study investigates the use of a natural polymer from Swietenia macrophylla (Mahogany), modified with metal nanoparticles (MNPs), namely silver oxide (Ag₂O), zinc oxide (ZnO), and silver-doped zinc oxide (Ag-ZnO), for petroleum wax inhibition. Material characterization was conducted using FTIR, TGA and GC-MS analyses, while performance evaluation employed rheological measurements, Cross-Polarized Microscopy (CPM), and pour point testing. GC-MS analysis revealed the presence of oxygenated fatty acid esters such as glycidyl oleate (59.61%) and glycidyl palmitate (16.86%). These compounds indicate the presence of hydrocarbon-compatible and surface-active constituents beneficial for wax crystal modification. FTIR spectra further confirmed carbonyl, aliphatic hydrocarbon, and ether functionalities associated with natural wax-mitigation compounds and effective MNP binding sites. The application of 2 wt% polymeric materials demonstrated significant wax inhibition performance. The unmodified polymer reduced the activation energy (Ea) for crude oil flow by 49.4 kJ·mol⁻¹ from the virgin crude oil value of 213.6 kJ·mol⁻¹. The polymer + ZnO formulation achieved the highest pour point reduction of 1.72 °C, while polymer + Ag-ZnO recorded the greatest viscosity reduction of 77.1% at 1 s⁻¹ and 91.6% at 200 s⁻¹. This study demonstrates, for the first time, the potential of Swietenia macrophylla-derived nanocomposite polymers as sustainable and effective wax mitigation agents for waxy crude oil systems. Full article