Search Results (967)

This study investigated the potential of hazelnut wood (Corylus avellana L.) as an alternative raw material in the production of single-layer structural particleboards. Boards with a target density of 700 kg m⁻³ and thickness of 13 mm were manufactured using varying substitution levels (5%, 10%, 25%, 50% and 100%) of hazel wood particles relative to industrial pine (Pinus sylvestris L.) particles. Phenol-formaldehyde (PF) resin was used as the adhesive at a 15% resination rate. Mechanical and physical properties, including modulus of rupture (MOR), modulus of elasticity (MOE), internal bond (IB), screw withdrawal resistance (SWR), water absorption (WA), and thickness swelling (TS), were evaluated according to relevant European standards. Density profiles (DP) were also assessed. The results showed that while higher hazel content reduced bending strength (from 23.3 N mm⁻² for reference to 18.7 N mm⁻² for 100% hazel wood board) and stiffness (from 3515 N mm⁻² for reference to 2520 N mm⁻² for 100% hazel wood board), most boards met standard mechanical requirements of EN 312 for P3 and P5 boards. Notably, IB strength improved significantly at higher hazel content, with the 100% variant (2.07 N mm⁻²) exceeding the reference board (1.57 N mm⁻²). Screw withdrawal resistance also increased with hazel wood addition (from 235 N mm⁻¹ for reference to 262 N mm⁻¹ for 100% hazel wood board), linked to its higher density. However, water resistance and dimensional stability worsened with increasing hazel content, particularly in bark-containing particles, leading to excessive thickness swelling after prolonged water exposure. Thickness swelling after 24 h of soaking rose from 16.36% for the reference board to 20.13% for the 100% hazel wood board. Density profiles revealed a more uniform internal structure in boards with higher hazel content. Overall, hazelnut wood shows promise as a partial substitute for pine in particleboard production, especially at moderate substitution levels, though limitations in moisture resistance must be addressed for broader industrial application. Full article

To investigate the effect of body size on muscle quality of common carp (Cyprinus carpio L.), we systematically tracked the dynamic changes in nutrient content, texture, and volatile organic compounds (VOCs) among small-sized (~100 g), medium-sized (~250 g), and large-sized (~600 g) fish (SYRC, MYRC, and HYRC, respectively) over a 30-week feeding trial. The results indicated that the HYRC showed significantly reduced moisture and lipid content, along with increased protein content, hydroxyproline, hardness, and chewiness compared to the SYRC (p < 0.05). The long-chain polyunsaturated fatty acids (LC-PUFAs) and fish lipid quality in the MYRC were significantly lower than those in both the SYRC and HYRC (p < 0.05). The HYRC demonstrated an elevated health-promoting index and a reduced atherogenicity value compared to the SYRC (p < 0.05). The contents of alcohol, ketones, and furans in the HYRC increased by 32.53%, 44.62%, and 144.29%, respectively, compared with those in the SYRC (p < 0.05), including key VOCs in aquatic products such as oct-1-en-3-ol and pent-1-en-3-ol. In conclusion, the SYRC have higher levels of LC-PUFAs and lower hardness; the MYRC have poor levels of LC-PUFAs; and the HYRC have an optimal synergy of nutrition, texture, and VOCs, but the overaccumulation of undesirable VOCs requires mitigation. This provides theoretical references and data support for fish quality optimization, processing, and consumption guidelines. Full article

This paper presents the research results on the synthesis of rhenium catalysts MTO, Re₂O₇/Al₂O₃, and M-Re₂O₇/Al₂O₃ (where M = Ni, Ag, Co, Cu) from rhenium compounds (ammonium perrhenate, perrhenic acid, nickel(II) perrhenate, cobalt(II) perrhenate, zinc perrhenate, silver perrhenate, and copper(II) perrhenate) derived from waste materials. Methyltrioxorhenium (MTO) was obtained from silver perrhenate with a yield of over 80%, whereas when using nickel(II), cobalt(II), and zinc perrhenates, the product was contaminated with tin compounds and the yield did not exceed 17%. The Re₂O₇/Al₂O₃ and M-Re₂O₇/Al₂O₃ catalysts were obtained from the above-mentioned rhenium compounds. Alumina obtained in a calcination process of aluminum nitrate nonahydrate was used as a support. The catalysts were characterized in terms of their chemical and phase composition and physicochemical properties. Catalytic activity in model reactions, such as cyclohexene epoxidation and hex-1-ene homometathesis, was also studied. MTO obtained from silver perrhenate showed >70% activity in the epoxidation reaction, thus surpassing commercial MTO (1.0 mol% MTO, room temperature, and reaction time—2 h). Ag-Re₂O₇/Al₂O₃, Cu-Re₂O₇/Al₂O₃, and H-Re₂O₇/Al₂O₃ catalysts were inactive, while Co-Re₂O₇/Al₂O₃ and Ni-Re₂O₇/Al₂O₃ showed low activity (<43%) in the hex-1-ene homometathesis reaction. Only Re₂O₇/Al₂O₃ catalysts achieved >70% activity in this reaction (2.5 wt% Re, room temperature, and reaction time—2 h). The results indicate the potential of using rhenium compounds derived from waste materials to synthesize active catalysts for chemical processes. Full article

The transition to sustainable energy systems demands efficient recycling methods for critical raw materials like lithium. In this study, we present a new class of pH- and light-switchable flotation collectors based on isomeric derivatives of the natural product Punicine, termed inverse Punicines. These amphoteric molecules were synthesized via a straightforward four-step route and structurally tuned for hydrophobization by alkylation. Their performance as collectors was evaluated in microflotation experiments of lithium aluminate (LiAlO₂) and silicate matrix minerals such as melilite and calcium silicate. Characterization techniques including ultraviolet-visible (UV-Vis), nuclear magnetic resonance (NMR) and electron spin resonance (ESR) spectroscopy as well as contact angle, zeta potential (ζ potential) and microflotation experiments revealed strong pH- and structure-dependent interactions with mineral surfaces. Notably, N-alkylated inverse Punicine derivatives showed high flotation yields for LiAlO₂ at pH of 11, with a derivative possessing a dodecyl group attached to the nitrogen as collector achieving up to 86% recovery (collector conc. 0.06 mmol/L). Preliminary separation tests showed Li upgrading from 5.27% to 6.95%. Radical formation and light-response behavior were confirmed by ESR and flotation tests under different illumination conditions. These results demonstrate the potential of inverse Punicines as tunable, sustainable flotation reagents for advanced lithium recycling from complex slag systems. Full article

Current treatments against leukemia present several limitations, prompting the search for new therapeutic agents, particularly those derived from natural products. In this context, structural modifications were performed on the triterpene 3α,24-dihydroxylup-20(29)-en-28-oic acid (T1), isolated from Phoradendron wattii. Among the five derivatives obtained, 3α,24-dihydroxy-30-oxolup-20(29)-en-28-oic acid (T1c) exhibited the highest activity, with an IC₅₀ value of 12.90 ± 0.1 µM against THP-1 cells. T1c significantly reduced cell viability in both acute lymphoblastic leukemia (CCRF-CEM, REH, JURKAT, and MOLT-4) and acute myeloid leukemia (THP-1) cell lines, inducing apoptosis after 48 h of treatment, while showing minimal cytotoxicity toward normal mononuclear cells (MNCs). In silico molecular docking studies were conducted against three key protein targets: BCL-2 (B-cell lymphoma 2), EGFR (epidermal growth factor receptor, tyrosine kinase domain), and FLT3 (FMS-like tyrosine kinase 3). The lowest binding energies (kcal/mol) observed were as follows: T1–BCL-2: −10.12, EGFR: −12.75, FLT3: −14.05; T1c–BCL-2: −10.23, EGFR: −14.50, FLT3: −14.07; T2–BCL-2: −11.59, EGFR: −15.00, FLT3: −14.03. These findings highlight T1c as a promising candidate in the search for anti-leukemic drugs which deserves further study. Full article

Lubrication between the rail gauge face and wheel flange is necessary to improve vehicle performance and reduce component wear. One way to achieve this is to use a solid stick loaded against the wheel flange. This paper details twin-disc testing of eight stick products according to Annex H of EN 15427-2-1:2022 (previously Annex L of EN 16028:2012) and then describes a new assessment methodology using conditions more relevant to field application. EN 15427-2-1:2022 specifies a test involving the application of the product during wheel–rail specimen contact. Once a specified time has elapsed, product application ceases, and performance is assessed as the time taken for the friction coefficient to return to a nominal dry value. This is described as “retentivity”. In the new test, the product is applied whilst wheel and rail are out of contact, to allow the product to build up on the wheel, then the specimens are put into contact, under conditions representing 150 m of continuous, heavy flange contact; this process is repeated a set number of times. The new test showed that products that failed the current friction criteria successfully protect the wheel and rail from wear, which is ultimately the aim of the product application. Full article

The paper investigates the process of degumming substandard soybean oil using an enzyme complex of phospholipases to prepare it as a feedstock for biodiesel production. Dehumidification is an important refining step aimed at reducing the phosphorus content, which exceeds the permissible limits according to ASTM, EN, and ISO standards, by re-moving phospholipids. The enzyme complex of phospholipases includes phospholipase C, which specifically targets phosphatidylinositol, and phospholipase A2, which catalyzes the hydrolysis of phospholipids into water-soluble phosphates and lysophospholipids. This process contributes to the efficient removal of phospholipids, increased neutral oil yield, and reduced residual oil in the humic phase. The use of an enzyme complex of phospholipases provides an innovative, cost-effective, and environmentally friendly method of oil purification. The results of the study demonstrate the high efficiency of using the phospholipase enzyme complex in the processing of substandard soybean oil, which allows reducing the content of total phosphorus to 0.001% by weight, turning it into a high-quality raw material for biodiesel production. The proposed approach contributes to increasing the profitability of agricultural raw materials and the introduction of environmentally friendly technologies in the field of renewable energy. Full article

Calcipotriol, a synthetic vitamin D₃ analogue widely used in psoriasis treatment, requires a detailed stability assessment due to its topical application and potential exposure to UV radiation. As a drug applied directly to the skin, calcipotriol is particularly susceptible to photodegradation, which may affect its therapeutic efficacy and safety profile. The present study focuses on the analysis of calcipotriol photostability. An advanced UHPLC/MS^E method was employed for the precise determination of calcipotriol and its degradation products. Particular attention was given to the effects of commonly used organic UV filters—approved for use in cosmetic products in both Europe and the USA (benzophenone-3, dioxybenzone, meradimate, sulisobenzone, homosalate, and avobenzone)—on the stability of calcipotriol. Unexpected degradation of calcipotriol was observed in the presence of sulisobenzone. Importantly, this effect was consistently detected in methanolic solution and in the pharmaceutical formulation containing calcipotriol and betamethasone, which is particularly significant from a practical perspective. This finding underscores the necessity of evaluating photostability under real-life conditions, as cosmetic ingredients, when co-applied with topical drugs on the skin, may substantially influence the stability profile of the pharmaceutical active ingredient. The research resulted in the first-time characterization of four degradation products of calcipotriol. The degradation process was found to primarily affect the E-4-cyclopropyl-4-hydroxy-1-methylbut-2-en-1-yl moiety, causing its isomerization to the Z isomer and the formation of diastereomers with either the R or S configuration. Computational analyses using the OSIRIS Property Explorer indicated that none of the five degradation products exhibit a toxicity effect, whereas molecular docking studies suggested possible binding of two of the five degradation products of calcipotriol with the VDR. Full article

Hotpot dishes are widely favored by consumers for their flavor profiles developed during the cooking process. This study investigated the quality characteristics and volatile compounds (VOCs) of donkey meat slices across varying boiling durations (0–42 s) using gas chromatography–ion mobility spectrometry (GC-IMS). The results demonstrated that donkey meat boiled for 12–18 s exhibited optimal characteristics in terms of meat retention, color parameters, shear force values, and pH measurements. Forty-eight distinct VOCs were identified in the samples, with aldehydes, alcohols, ketones, acids, furans, and esters representing the predominant categories. Among these compounds, 18 were identified as characteristic aroma compounds, including 3-hexanone, 2, 3-butanedione, and oct-1-en-3-ol. Samples subjected to different boiling durations were successfully differentiated through topographic plots, fingerprint mapping, and multivariate analysis. The abundance and diversity of VOCs reached peak values in samples boiled for 12–18 s. Furthermore, 28 VOCs were identified as potential markers for distinguishing between different boiling durations, including 2-butoxyethanol D, benzaldehyde D, and (E)-2-pentenal D. This study concludes that a boiling duration of 12–18 s for donkey meat during hotpot preparation yields optimal quality characteristics and volatile flavor compound profiles and provides valuable insights for standardizing cooking parameters in hotpot preparations of other meat products. It is necessary to confirm this finding with sensory evaluations in further research. Full article

During the Swern oxidation of 3-methylbut-3-en-1-ol, an unexpected C-C bond formation product, 3-methyl-2-(methylthio)but-2-enal, was obtained. Its structure was characterized using ¹H-NMR, ¹³C-NMR, and HRMS. Based on the classical Swern oxidation mechanism and the unique structural features of the substrate, we propose a plausible reaction pathway. This discovery not only provides insights into the selection of oxidation conditions for 1, 1-disubstituted homoallylic alcohols with analogous structures but also offers a viable synthetic route for the preparation of compounds containing the 3-methyl-2-(methylthio)but-2-enal motif. Full article

The synthesis of cannabigerol—a cannabinoid with significant pharmaceutical potential—is described. The synthesis involves four stages. In the first step, (E)-non-3-en-2-one reacts with dimethyl malonate to yield a cyclic enone, which is subsequently oxidized with bromine to produce the olivetol ester. This ester then undergoes an alumina-catalyzed coupling reaction with geraniol, followed by ester hydrolysis to obtain cannabigerol. By modifying the chain length of the enone in the initial step and employing allylic alcohols other than geraniol, a range of cannabigerol derivatives can be synthesized, including the natural product cannabigerovarin. Full article

The objective of this paper is to evaluate the capability of various steel rope manufacturers to maintain the desired variability within the strength class of wires used in the production of steel ropes. From a service life perspective, it is optimal to achieve the narrowest possible strength class interval for wires integrated into steel ropes. However, the applicable EN 12385 standards permit a relatively wide interval of allowable strength class dispersion. The analysis encompasses 112 steel ropes tested over the period from 2000 to 2025. For the purpose of evaluating rope quality in terms of wire strength variability, the ropes were categorized into four quality classes. The assessment of wire strength was conducted using statistical quality control methods, specifically through the application of control charts. Based on these methods, the stability and capability of wire strength within each rope were verified. The results highlight the differences in wire strength performance across the evaluated quality classes. Full article

Background: Bariatric surgeries, specifically laparoscopic sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB), are a common intervention for morbid obesity, significantly affecting food tolerance and quality of eating. Understanding these changes is crucial for improving postoperative care and long-term success. Methods: This observational study at University Hospital Mannheim involved 91 patients, aged between 18 and 65 year, who underwent SG or RYGB between 2009 and 2019. Food tolerance was assessed between 25 days and 117 months after surgery using the validated score by Suter et al. (Food Tolerance Score, FTS) and an additional score evaluating tolerance to specific food groups and quality of life. Data on body composition were collected through Bioelectrical Impedance Analysis (BIA) at follow-up visits. Statistical analyses included linear mixed models to analyze the association of food tolerance with body composition changes. Results: The FTS indicated moderate or poor food tolerance in 62.6% of patients, with no significant differences between SG and RYGB. Considering the results of the additional score, food groups such as red meat, wheat products, raw vegetables, carbon dioxide, fatty foods, convenience food, and sweets were the most poorly tolerated food groups. A total of 57 of the participants had a baseline and follow-up BIA measurement. Postoperatively, a significant reduction in body weight and BMI as well as in BIA parameters (fat mass, lean mass, body cell mass, and phase angle) was found. Quality of life improved after bariatric surgery and 76.9% rated their nutritional status as good or excellent, despite possible food intolerances. Conclusions: Bariatric surgery significantly reduces weight and alters food tolerance. Despite moderate or poor food tolerance, patients reported high satisfaction with their nutritional status and quality of life. Detailed food tolerance assessments and personalized dietary follow-ups are essential for the early detection and management of postoperative malnutrition, ensuring sustained weight loss and improved health outcomes. Full article

Medicinal mushroom production utilising rural cultivation (solid state fermentation) requires approximately six months compared to culinary mushroom production (7 days). Urban cultivation (submerged liquid fermentation) can be used as a sustainable method of producing medicinal mushroom biomass. In this study, chicken patties were fortified with liquid-fermented Ganoderma lucidum flour (GLF) and Pleurotus djamor mushroom biomass flour (PDF) at concentrations of 3%, 6%, and 9%. These were compared to a negative control (0% mushroom flour chicken patty) and a commercial patty. Chicken patties fortified with 3% PDF and 9% GLF recorded the lowest cooking loss, at 5.55% and 10.3%, respectively. Mushroom chicken patties exhibited lower cooking losses and significant changes in colour and texture compared to control samples. Notably, 3% GLF chicken patty achieved the highest overall acceptability score of 6.55 followed by 9% PDF chicken patty (6.08) (p < 0.05). Biomass flour of liquid-fermented Ganoderma lucidum (ENS-GL) and Pleurotus djamor (ENS-PD) were extracted for their endopolysaccharide and analysed for their functional properties. All elemental, FT-IR, and NMR spectroscopy analyses revealed the existence of a comparable beta-glucan polymer structure, linkages, and absorptions when compared to the Laminarin standard. In addition, ENS-GL also proved to possess higher antimicrobial activities and significant antioxidant levels (DPPH-scavenging activity, ferric reduction potential and total phenolic content) compared to ENS-PD. Overall, this study revealed that sustainable liquid-fermented Ganoderma lucidum, a medicinal mushroom, outperformed Pleurotus djamor, a culinary mushroom, as a potential alternative flour for combating hunger in the future. Full article

Satellite-based monitoring of atmospheric column-averaged dry-air mole fraction (XCH₄) is essential for quantifying methane (CH₄) emissions, yet uncharacterized spatially varying biases in XCH₄ observations can cause misattribution in flux estimates. This study assesses the potential of the upcoming TanSat-2 satellite mission to estimate China’s CH₄ emission using a series of Observing System Simulation Experiments (OSSEs) based on an Ensemble Kalman Filter (EnKF) inversion framework coupled with GEOS-Chem on a 0.5° × 0.625° grid, alongside an evaluation of current TROPOMI-based products against Total Carbon Column Observing Network (TCCON) observations. Assuming a target precision of 8 ppb, TanSat-2 could achieve an annual national emission estimate accuracy of 2.9% ± 4.2%, reducing prior uncertainty by 84%, with regional deviations below 5.0% across Northeast, Central, East, and Southwest China. In contrast, limited coverage in South China due to persistent cloud cover leads to a 26.1% discrepancy—also evident in pseudo TROPOMI OSSEs—highlighting the need for complementary ground-based monitoring strategies. Sensitivity analyses show that satellite retrieval biases strongly affect inversion robustness, reducing the accuracy in China’s total emission estimates by 5.8% for every 1 ppb increase in bias level across scenarios, particularly in Northeast, Central and East China. We recommend expanding ground-based XCH₄ observations in these regions to support the correction of satellite-derived biases and improve the reliability of satellite-constrained inversion results. Full article