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The Application of Recycled Jute Non-woven Material Loaded with Zinc Ions as Substrates for Plant Growth
No full textThe challenges posed by polluted effluents containing heavy metal ions and the increasing amounts of textile waste necessitate prompt action. In response to these environmental concerns, a non-woven sorbent made from jute fibers, recycled from the carpet industry, has been developed. To enhance the sorption capacity for Zn2+ ions, the jute fibers were modified with the biopolymer alginate. The successful application of the alginate coating on the jute fibers was proved through FTIR and FESEM analyses. The presence of carboxyl and hydroxyl groups in alginate led to a 68% increase in sorption capacity. An increase in the initial concentration of ions, pH, and temperature was found to facilitate larger uptake of Zn2+ ions. To mitigate environmental risks associated with metal-saturated sorbents and accumulating textile waste, while addressing zinc deficiency in plants, the developed sorbents were evaluated as growth substrates for Lactuca sativa (lettuce) and Setaria viridis (green bristlegrass), two economically important plant species. Jute waste-growth substrates coated with alginate and enriched with Zn can provide mechanical support, humidity, and a source of this essential micronutrient to plants during early growth stages. Optimization of Zn concentration in the growth substrate can lead to the elevated levels of Zn in plant tissues, but also to the increased content of valuable bioactive compounds. Thus, recycling highly biodegradable natural jute waste and reusing it as plant growth substrates can have profound effects on environmental protection and can also be beneficial to human nutrition and health
Exploring the functional potential of bent-core liquid crystal-based molecules with an amide linking group
No full textA new series of bent-core molecules containing a photoactive π -conjugated structure (azobenzene, stilbene or cyanostilbene) linked to the central aromatic ring by an amide group was synthesized and characterized. Their liquid crystalline properties were analyzed in relation to the molecular structure and compared with amide-containing bent-core liquid crystals from the literature. Replacement of the azobenzene structure with a unit based on stilbene, either with or without a cyano substituent, accounted for the most significant differences in liquid crystalline behavior among the synthesized compounds. Azobenzene compound exhibited an enantiotropic B7-type phase, while (cyano)stilbene compounds formed a monotropic B1Rev phase. Cyanostilbene derivatives were fluorescent and showed aggregation-induced emission (AIE) enhancement. Furthermore, these compounds showed mechanofluorochromism, as observable emission changes in the solid state as a result of mechanical grinding. These changes turned to be reversible upon fuming with tetrahydrofuran vapor. Quantum-chemical calculations were employed to provide a detailed analysis of the most probable conformers, the impact of the cyano group orientation on the transverse and longitudinal components of the molecular dipole moment, and the electronic properties. The obtained results offer valuable molecular design guidelines for the development of new stimuli-responsive self-assembled materials
COVID-19 ante portas: Empirical formula, growth reactions and thermodynamic properties of biosynthesis and antigen-receptor binding of the Omicron XFG variant of SARS-CoV-2
No full textNo one walks alone. In 2019, humanity obtained a permanent companion called SARS-CoV-2. SARS-CoV-2 lives with its human host, adapts to the human host and evolves, in a similar process to that in the human host. The XFG variant is the latest in the sequence of variants that appeared during the process of adaptation. Science has intensively followed the process of evolution of SARS-CoV-2. It was noticed that in accordance with the expectations of the evolution theory, SARS-CoV-2 variants have become less pathogenic and more infective. However, there is a great concern in the general public because of the millions of casualties during the COVID-19 pandemic. In this paper, chemical and thermodynamic characterization was performed: empirical formulas, reactions of biosynthesis, antigen-receptor binding reaction and thermodynamic properties of live matter, biosynthesis and binding were determined, mechanistic model of virus-host interactions was developed and the driving force of biological processes during the life cycle of the virus was determined
Decarbonizing ethylene production via renewable energy electrification: A techno-economic and environmental assessment
No full textThe transition to sustainable production in the chemical industry is essential for achieving global decarbonization targets. This study explores the electrification of an ethylene plant by replacing its conventional natural gas (NG) boilers with electric boilers powered by renewable energy sources. Unlike previous works that focus on single-technology substitution, this paper provides a comprehensive, system-level assessment of ethylene plant electrification by comparing integrated scenarios of concentrated solar power (CSP), photovoltaic (PV) solar energy, and wind power. The optimal configuration is evaluated based on economic feasibility, environmental impact, and land requirements, offering a methodology that can be adopted for other energy-intensive petrochemical processes. The analysis reveals that while wind energy presents the lowest cost among the available renewable sources, its significant land footprint poses a major challenge, particularly when direct power supply to electric boilers is required. Conversely, CSP, despite being the most expensive option, offers the advantage of simultaneously generating steam and power, enhancing system efficiency. PV-based electrification, positioned between wind and CSP in terms of cost and land use, presents a balanced alternative. The study also investigates the prospects of supplementing on-site renewable generation with imported clean electricity to overcome land constraints and improve operational resilience. The findings provide valuable insights into the trade-offs between cost, sustainability, and spatial constraints in electrifying ethylene production, and they outline potential pathways toward a low-carbon, robust and scalable future for the petrochemical sector
Hydrogels based on poly(methacrylic acid) prepared via bio-catalysis using soybean waste peroxidase for anti-inflammatory applications
No full textAn eco-friendly system based on soybean coats peroxidase, vitamin C, and hydrogen peroxide (SP/VC/H2O2) was used for the first time for free radical polymerization of methacrylic acid. Soybean coats make up approximately 5% of the total soybean mass and are rich in peroxidase, so their utilization for enzyme extraction therefore would contribute to waste valorisation. By employing the SP/VC/H2O2 initiation system, pH-sensitive poly(methacrylic acid) (PMA) hydrogels
were successfully prepared through simple, energy-efficient, and eco-friendly one-pot synthesis under ambient conditions. The main objective was to further reduce the reaction time and amount of hydrogen peroxide compared to the method that utilized VC/H2O2 initiation system (24 h and 100 µL), and these were successfully decreased to 6 h and 20 µL, respectively. FTIR and SEM analyses confirmed the PMA hydrogel composition and revealed a regular porous structure, respectively. Increase in SP activity, H2O2, VC, or crosslinker amount led to higher values of
compressive strength and reduced values of equilibrium swelling degree. The PMA hydrogels exhibited pH dependent swelling, which enabled controlled release of anti-inflammatory drug – diclofenac for 24 h at pH 6.8 (a pH value selected to simulate the pH in human small intestines and inflamed tissue microenvironments). The anti-inflammatory effect of the PMA hydrogel was confirmed by testing it on bovine chondrocytes. This eco-friendly approach in the preparation of PMA hydrogels resulted in material with easily tunable properties and potential for treatment
of inflammation
Source-Specific Probabilistic Human Exposure to Potentially Toxic Elements from Private Drinking Water Wells in a Highway Construction Valley
No full textPotentially toxic elements (PTEs) originating from natural processes and human activities pose significant hazards to ecosystems and public health. However, there is very limited information on groundwater PTE contamination in the vicinity of road construction sites. This study incorporated various pollution indices, self-organizing maps (SOM), positive matrix factorization (PMF), and probabilistic Monte Carlo simulation (MCS) to investigate the occurrence, contamination levels, sources, and potential human health risks of PTEs from groundwater in a highway construction area in Serbia. Most PTE concentrations were within the drinking water guidelines, and groundwater fell within the no pollution to low pollution categories based on the pollution indices. The SOM distinguished three clusters corresponding to different pollution sources. The PMF analysis further validated the SOM findings, indicating that the dominant pollution sources were natural processes, agricultural practices, and traffic/highway construction, accounting for 35.0%, 33.3%, and 31.7%, respectively. The deterministic health risk assessment revealed that non-carcinogenic and carcinogenic health risks were generally below safe thresholds. Non-carcinogenic risk for adults and children was unacceptable in 2.4% and 7.1% of the samples, respectively. The carcinogenic risk for children was acceptable, whereas adults faced carcinogenic risk in 7.1% of the samples. The outcomes of the MCS of risks demonstrated that natural processes were the primary source of non-carcinogenic human health risk, whereas agricultural practices were identified as the principal contributor to carcinogenic risk. These findings provide novel insights and represent the first integrated SOM-PMF-MCS assessment of groundwater PTEs associated with highway construction
Structural and functional characterisation of hydrogels prepared from Porphyridium purpureum under acidic conditions
No full textThe red microalgae Porphyridium purpureum exhibits exceptional nutritional properties due to rich protein content, extracellular polysaccharides, polyunsaturated fatty acids, vitamins, and minerals. The coloured and bioactive phycobiliproteins make this microalga a valuable source for developing innovative food products. Herein, we developed a simple procedure to induce the formation of coloured hydrogels (POR) from P. purpureum under acidic conditions (pH 2) by inhibiting the repulsion of charged groups and facilitating polysaccharide chain association. We further investigated the effects of adding alginate at a 0.5 % concentration on the gel structure (POR ALG) and techno-functional properties. The resulting vividly coloured hydrogels were characterised in terms of microstructure (via SEM and confocal microscopy), functional groups (FTIR), rheological behaviour, water uptake and water-holding capacity, digestibility, and antioxidant activity. Alginate addition significantly improved the gel consistency (POR ALG), decreased porosity, and increased the storage modulus by one order of magnitude compared to POR gel. Confocal microscopy revealed that alginate inhibited phycobiliprotein agglomeration, reduced fluorescence, and provided more uniform protein distribution. The water uptake capacity was notably higher in POR ALG hydrogel at pH 2, whereas POR hydrogel had the highest capacity at neutral pH. In vitro digestion studies demonstrated that the hydrogels resisted gastric digestion, while bioactive (chromo)peptides are released in the intestinal phase, thereby preserving their antioxidant activity. Lyophilisation emerged as the preferred drying method, maintaining rehydration potential and structural integrity. The developed P. purpureum-based hydrogels demonstrate significant potential as functional food ingredients, offering bioactive benefits, vibrant colour stability, and protection for sensitive molecules during digestion
Tailoring functional properties of gum Arabic and partially hydrolyzed guar gum-based delivery systems for phenylethanoid glycosides from Mountain Germander (Teucrium montanum L.)
No full textThe growing popularity of plant extracts as valuable sources of bioactive compounds is clearly reflected in the investment in technological solutions that ensure stability and more convenient integration into food formulations. The aim of this study was to investigate the effect of secondary polymers - hydrolyzed collagen (COL), kappa-carrageenan (CAR) and carboxymethylcellulose (CMC) on the physico-chemical and functional properties of spray-dried microparticles based on gum Arabic (GA) and partially hydrolyzed guar gum (GG) for the delivery of phenylethanoid glycosides from Mountain Germander extract. The viscoelastic properties of the feed solutions as well as the physico-chemical, bioactive and thermal properties of the MG microparticles were determined for all formulations. Improved electrostatic repulsion was observed for the GA_CAR and GG_CMC formulations. The addition of CMC improved the surface morphology and reduced the wettability of the microparticles, thus providing controlled release of the PhG. The ATR-FTIR spectra revealed high affinity of the PhG to interact with polar functional groups of examined carrier matrices. The introduction of COL into the GA solution as well as CMC into the GG solution significantly (p < 0.05) reduced the encapsulation efficiency by max. 25 %, depending on the PhG compound analyzed. The results of this study reveal the suitability of GA and GG for the retention of PhG as well as the emerging potential of CMC for modifying the functional properties of the hydrophilic carrier matrix
Heavy metals in fly ash: chemometric modelling of extraction parameters and environmental and health risk assessment
No full textThe growing demand for energy, primarily produced through coal combustion in thermal power plants, leads to the generation of large quantities of fly ash containing potentially hazardous heavy metals. Inadequate disposal of this kind of waste can cause significant environmental harm. A proper handling of this waste material requires a comprehensive physicochemical characterization, and implementation of different analytical methods, in order to obtain as most complete insight into its qualitative and quantitative composition as possible. Standard digestion methods are associated with problems such as: 1) the use of HF, 2) digestion at high temperatures, and 3) long digestion time. Hence, in this work, a microwave-assisted acid digestion method using HNO₃/H₂SO₄/H₂O₂ with V₂O₅ as a catalyst was developed and optimized and compared with the total digestion method (HF/HNO₃/HCl). The influence of digestion temperature and time on the extraction efficiency of heavy metals from fly ash was evaluated. Higher temperatures improved the recovery of Cd, Co, Cr, Ni, Mn, Pb, and Zn (1.5 to 7 times), while lower temperatures favoured the extraction of volatile elements such as Hg (1 to 1.7 times) and As (5 to 15 times). The developed method detected higher concentrations of As (1 to 4 times) and Hg (10 to 80 times) compared to the HF/HNO₃/HCl method during the digestion process at 200 °C. Principal component analysis (PCA) grouped elements based on their behaviour during digestion, while hierarchical cluster analysis (HCA) revealed groupings based on digestion conditions. The study also included ecological and health risk assessments. All samples were categorized as having very high ecological risk, primarily due to elevated levels of Hg, Cd, and As. Health risk analysis identified Hg, Cr, Cd, and As, as the elements of highest concern. These findings emphasize the importance of optimized digestion protocols for accurate risk assessment and support the need for improved fly ash management strategies in the context of environmental protection
Integrated assessment of radiological and heavy metal(loid) hazards in soil at a remediated oil drilling site
No full textThis study investigated the heavy metal (loid) and radionuclide contamination in the soil at a remediated oil drilling site. Radionuclide activity concentrations were within acceptable levels, while elevated concentrations were detected for Cd, Hg, Zn, As, and Cu. Positive matrix factorization identified four distinct sources: oil drilling, remediation process, industrial activities, and natural sources. The radiological risk indices indicated no significant gamma radiation hazard, and non-carcinogenic and carcinogenic indices were within the acceptable levels. The spatial distribution maps of health risk indices followed the distribution pattern of the five heavy metal(loid)s, revealing a single hotspot