Alcohol Acid Research Articles

Recent Advance of Sustainable Polymers for Packaging Applications

The extensive application of non-renewable polymers has brought about deep environmental concerns, demonstrating the immediate requirement for new biodegradable and biobased packaging choices. The work offers an in-depth look at a wide array of degradable and biobased polymers like Polylactic Acid (PLA), Polyhydroxyalkanoates (PHA), and Polyvinyl Alcohol (PVOH), as well as starch and cellulose materials, discussing their qualities, uses, and the issues faced in food packaging. These types of green polymers, either in new ways or from renewable sources, offer great advances not only from decomposition into harmless parts but also from the reduction of environmental damage. The essay covers the exploitation side of this material, be it the role of PLA in enzymatic, hydrolytic, or microbial degradations, or the main tactical function of PHA in terms of a water barrier aimed at preserving the quality of stored food. Additionally, the multifunctionality of these substances is represented anew in packaging dairy goods, such as fruits, and vegetables, and specialized applications like edible films or water-soluble bags. The participation of compostable polymers has become increasingly vital in the area of food packaging to meet consumers’ demands and to upgrade the present science technologies aimed at guiding food producers who are looking for more sustainability in their business.

Influence of maternal health status during pregnancy and the child´s medical history on molar-incisor hypomineralization in a group of Spanish children (aged 6-14 years): a retrospective case-control study.

Molar-incisor hypomineralization (MIH) is a qualitative enamel defect that is highly prevalent in children. It has been reported that patients with MIH have higher caries occurrence with an increased need and frequency of dental treatment compared to patients without MIH. The objective of this study was to analyze the association between MIH and a series of factors related to maternal health status during pregnancy and children´s medical history in early childhood. A retrospective study of cases (patients with MIH) and controls (patients without MIH) was designed between 2023 and 2024. A total of 280 children (cases = 140; controls = 140) aged 6 to 14 years (138 boys and 142 girls) were examined according to the European Academy of Pediatric Dentistry (EAPD) criteria for MIH. A survey was carried out with mothers regarding the potential exposure of their children to etiological factors of MIH. Possible prenatal and postnatal etiological factors were obtained through a personal interview with the patients' mothers. The statistical analysis was carried out with the contrast test and the chi-square test. During pregnancy, folic acid consumption, alcohol intake, systemic viral and/or bacterial infections, and gestational diabetes were statistically significantly related to MIH, as were breastfeeding, asthma, and corticosteroid consumption during childhood. Although there are different factors that may have statistically significant relationships with MIH, they cannot be predicted. Therefore, longitudinal studies, with a large sample size, are needed to determine the influence of prenatal and postnatal factors on the prevalence and severity of MIH in children.

Natural variation in the chickpea metabolome under drought stress.

Chickpea is the world's fourth largest grown legume crop, which significantly contributes to food security by providing calories and dietary protein globally. However, the increased frequency of drought stress has significantly reduced chickpea production in recent years. Here, we have performed a field experiment with 36 diverse chickpea genotypes to evaluate grain yield, photosynthetic activities and molecular traits related to drought stress. For metabolomics analysis, leaf tissue was collected at three time points representing different pod-filling stages. We identified L-threonic acid, fructose and sugar alcohols involved in chickpea adaptive drought response within the mid-pod-filling stage. A stress susceptibility index for each genotype was calculated to identify tolerance capacity under drought, distributing the 36 genotypes into four categories from best to worst performance. To understand how biochemical mechanisms control different traits for genetic improvement, we performed a differential Jacobian analysis, which unveiled the interplay between various metabolic pathways across three time points, including higher flux towards inositol interconversions, glycolysis for high-performing genotypes, fumarate to malate conversion, and carbon and nitrogen metabolism perturbations. Metabolic GWAS (mGWAS) analysis uncovered gene candidates involved in glycolysis and MEP pathway corroborating with the differential biochemical Jacobian results. Accordingly, this proposed data analysis strategy bridges the gap from pure statistical association to causal biochemical relations by exploiting natural variation. Our study offers new perspectives on the genetic and metabolic understanding of drought tolerance-associated diversity in the chickpea metabolome and led to the identification of metabolic control points that can be also tested in other legume crops.

The Critical Role of Phenylpropanoid Biosynthesis Pathway in Lily Resistance Against Gray Mold

Gray mold caused by Botrytis elliptica is one of the most determinative factors of lily growth and has become a major threat to lily productivity. However, the nature of the lily B. elliptica interaction remains largely unknown. Here, comparative transcriptomic and metabolomic were used to investigate the defense responses of resistant (‘Sorbonne’) and susceptible (‘Tresor’) lily cultivars to B. elliptica infection at 24 hpi. In total, 1326 metabolites were identified in ‘Sorbonne’ and ‘Tresor’ after infection, including a large number of phenylpropanoids. Specifically, the accumulation of four phenylpropanes, including eriodictyol, hesperetin, ferulic acid, and sinapyl alcohol, was significantly upregulated in the B. elliptica-infected ‘Sorbonne’ compared with the infected ‘Tresor’, and these phenylpropanes could significantly inhibit B. elliptica growth. At the transcript level, higher expression levels of F3′M, COMT, and CAD led to a higher content of resistance-related phenylpropanes (eriodictyol, ferulic acid, and sinapyl alcohol) in ‘Sorbonne’ following B. elliptica infection. It can be assumed that these phenylpropanes cause the resistance difference between ‘Sorbonne’ and ‘Tresor’, and could be the potential marker metabolites for gray mold resistance in the lily. Further transcriptional regulatory network analysis suggested that members of the AP2/ERF, WRKY, Trihelix, and MADS-M-type families positively regulated the biosynthesis of resistance-related phenylpropanes. Additionally, the expression patterns of genes involved in phenylpropanoid biosynthesis were confirmed using qRT-PCR. Therefore, we speculate that the degree of gray mold resistance in the lily is closely related to the contents of phenylpropanes and the transcript levels of the genes in the phenylpropanoid biosynthesis pathway. Our results not only improve our understanding of the lily’s resistance mechanisms against B. elliptica, but also facilitate the genetic improvement of lily cultivars with gray mold resistance.

Preparation and performance study of modified diatomite based PCM for construction

Phase change energy storage technology provides a good solution to the spatial and temporal mismatch of energy use in buildings, but organic solid–liquid phase change materials suitable for the building sector limit their application due to leakage problems. To mitigate the effects of the above problems, diatomite (DME) is designed as the carrier for encapsulation in this experiment. Adsorption performance of DME is improved through double effects of 600°C high-temperature calcination and hydrochloric acid modification. The binary low eutectic mixture was prepared by co-melting of lauric acid (LA) and octadecyl alcohol (OD) with mass ratio of 70:30. Shape-stabilized composite phase change material (SSCPCM) was prepared by vacuum adsorption method with LA-OD and DME with a mass ratio of 35:65 and the melting temperature and latent heat of SSCPCM are 39.10°C and 54.02 J/g. It was experimentally evaluated that the surface impurities of modified DME under microscopic conditions were removed and LA-OD was uniformly embedded in the micropores of DME, and the prepared SSCPCM was able to maintain a thermal inertia of 39°C with good thermal properties and thermal stability, thus SSCPCM could be used as a building energy-saving material to reduce building energy consumption, in addition to expanding the utilization of inorganic mineral materials.

Metabolic engineering of hairy root cultures in Beta vulgaris for enhanced production of vanillin, 4-hydroxybenzoic acid, and vanillyl alcohol.

The flavor of vanilla is a complex blend of compounds, with vanillin as the most prominent, along with vanillyl alcohol and 4-hydroxybenzoic acid. Natural vanillin extracted from vanilla beans is expensive, so researchers use heterologous synthesis to produce nature-identical vanillin in plant hosts. Consequently, alternative traditional farming and gathering methods are required to bridge the significant disparity between supply and demand. The current research successfully developed a method to induce hairy root formation from leaves. It integrated the Vanillin synthase (VpVAN) gene into transgenic hairy root lines of Beta vulgaris, synthesizing vanillin-related compounds. The presence of the VpVAN gene in transgenic roots was confirmed using PCR analysis. Additionally, RT-qPCR analysis demonstrated the expression of the VpVAN gene in the transgenic root lines. The transgenic hairy root clones H1, H2, and H5 showed enhanced vanillin production, vanillyl alcohol, and 4-hydroxybenzoic acid. Elicitation with methyl jasmonate (MJ) and salicylic acid (SA) further improved the production of these compounds in B. vulgaris hairy roots. The maximum hairy root biomass was observed after 60 days, with the maximum synthesis of vanillin and 4-hydroxybenzoic acid obtained from hairy root clones H5 and HR2, respectively. Vanillyl alcohol HR2 was obtained on the 45th day of cultivation. Elicitation with wound-associated hormone methyl jasmonate and salicylic acid enhanced the yield of vanillin, vanillyl alcohol, and 4-hydroxybenzoic acid, with a 215-fold increase in vanillin, a 13-fold increase in vanillyl alcohol, and a 21 fold increase in 4-hydroxybenzoic acid. The study results indicate that establishing transgenic hairy root cultures with the VpVAN gene is a promising alternative method for enhancing the production of vanilla flavor compounds such as vanillin, vanillyl alcohol, and 4-hydroxybenzoic acid. A cost-effective protocol has been developed to mass-produce phenolic compounds using a hairy root culture of B. vulgaris. This approach addresses the increasing demand for these substances while reducing the cost of natural vanillin production, making it suitable for industrial-scale applications.

Rumex japonicus Houtt. Leaves: the chemical composition and anti-fungal activity

BackgroundCandida albicans is a pathogenic commensal fungus. Trichophyton mentagrophytes and Trichophyton rubrum are the leading pathogens of dermatophysis. Rumex japonicus Houtt. has a miraculous effect on the treatment of tinea skin disease, but its mechanism has not been clarified. Purpose: This paper investigated the anti-fungal ingredients of the leaves of Rumex japonicus Houtt. (RJH-L) and the mechanism of the anti-fungal (Trichophyton mentagrophytes, Trichophyton rubrum and Candida albicans). MethodFirst, the chemical composition analysis of RJH-L was conducted by acid extraction and alcohol precipitation, high performance liquid chromatography (HPLC) and nuclear magnetic resonance spectroscopy (NMR); in vitro anti-fungal experiments were carried out, including the minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) spore germination rate, germ tube production rate, nucleic acid and protein leakage rate, biofilm structure, PCR, etc., to study the mechanism of action of RJH-L anti-fungal and anti-biofilm activity. ResultSeven monomer compounds were obtained: anthraquinones (rhein, emodin and aloe-emodin); polyphenols (ferulic acid, p-coumaric acid), and flavonoids (rutin and quercetin). The results of in vitro anti-fungal experiments showed that the extracts of RJH-L had strong inhibitory effect on both fungi (MIC: 1.96 µg/mL-62.50 µg/mL), of which emodin had the strongest effect on Trichophyton mentagrophytes; and rhein had the strongest effect on Candida albicans and Trichophyton rubrum. The above active components can inhibit the germination of fungal spores and germ tube, change cell membrane permeability, prevent hyphal growth, destroy the biofilm structure, and down-regulate the expression of agglutinin-like sequencefamily1 of biofilm growth. ConclusionThis study shows that RJH-L are rich in polyphenols, flavonoids, and anthraquinones, and play a fungicidal role.

Machine learning discrimination and prediction of different quality grades of sauce-flavor baijiu based on biomarker and key flavor compounds screening

The quality grade of base Baijiu directly determines the final quality of sauce-flavor Baijiu. However, traditional methods for assessing these grades often rely on subjective experience, lacking objectivity and accuracy. This study used GC-FID, combined with quantitative descriptive analysis (QDA) and odor activity value (OAV), to identify 27 key flavor compounds, including acetic acid, propionic acid, ethyl oleate, and isoamyl alcohol etc., as crucial contributors to quality grade differences. Sixteen bacterial biomarkers, including Komagataeibacter and Acetobacter etc., and 7 fungal biomarkers, including Aspergillus and Monascus etc., were identified as key microorganisms influencing these differences. Additionally, reducing sugar content in Jiupei significantly impacted base Baijiu quality. Finally, 11 machine learning classification models and 9 prediction models were evaluated, leading to the selection of the optimal model for accurate quality grade classification and prediction. This study provides a foundation for improving the evaluation system of sauce-flavor Baijiu and ensuring consistent quality.

Tropical Leaf Wax n‐Alkane and n‐Alkanoic Acid Reflect δD of Precipitation During Early Stages of Leaf Growth: Insights From an Isotope Labeling Experiment

AbstractThe hydrogen isotopic compositions of leaf‐wax n‐alkanes (δDalk) and n‐alkanoic acids (δDacid) reflect ambient climatic conditions (including precipitation δD values, δDprecip). However, the understanding of climatic conditions of exactly which period (i.e., early or entire period of the leaf's lifespan) these biomarkers preserve is still evolving. Previous studies on the δDalk and δDacid values, done only in extra‐tropical regions, mostly indicate that δDalk values are biased toward the early growing season whereas δDacid values are not biased toward any season. To decipher the seasonal bias in δDalk and δDacid records from tropics, we conducted a long‐duration experiment wherein deciduous and evergreen species were grown using normal water (δD = −2‰) during early stages of the leaf growth and later using isotopically labeled water (δD = 1,000‰). Our experiment revealed (a) in deciduous and evergreen species, δDalk and δDacid values reflect δDprecip during early stages of the leaf growth, (b) synchronous synthesis of n‐alkanes and n‐alkanoic acids, and (c) in deciduous species, minor incorporation of the previous year's photosynthates in leaf wax pool of the current year's mature leaves. Our study suggests that δDalk and δDacid records in the tropics are biased toward the climatic conditions prevailing during early stages of leaf growth. This bias should be considered while comparing the δDprecip values generated from leaf wax proxy records and isotope‐enabled atmospheric circulation models.

The combination of hydrogels and rutin-loaded black phosphorus nanosheets treats rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease characterized by inflammation, joint pain, and cartilage degradation. The fluctuating nature of RA often necessitates long-term oral administration of treatment drugs, which can unfortunately lead to adverse effects such as gastrointestinal discomfort and hepatic and renal dysfunction. Therefore, a percutaneous local delivery method for the release of inflammatory modulators in arthritic joints represents a promising therapeutic approach for RA. In this study, we have developed a unique and innovative therapeutic platform (named BP-Rut@Gel). This hydrogel was formulated by incorporating the drug Rutin (Rut) into Black phosphorus nanosheets (BP) and subsequently integrating them within a Hyaluronic Acid (HA) and Polyvinyl Alcohol (PVA) matrix to create a composite hydrogel. Notably, Secondly, photothermal therapy (PTT) under Near-Infrared Irradiation (NIR) and anti-inflammatory drugs synergistically worked together to efficiently quell inflammation and enhance therapeutic effectiveness. Additionally, toxicity experiments have revealed that our synthesized black phosphorus nanosheet composite hydrogel possesses excellent biocompatibility and significantly reduces the inflammatory response in RA joints. Given these remarkable properties, our BP-Rut@Gel hydrogel held significant promise and demonstrated immense clinical potential for the treatment of RA.

Enhancement of wound dressings through cerium canadate and hydroxyapatite-infused hyaluronic acide and PVA membranes: A comprehensive characterization and biocompatibility study

This study explores the emhancement of advanced wound dressings by enhancing traditional bandages with suitable biomedical materials. We utilized Hyaluronic Acid (HA) and Polyvinyl Alcohol (PVA) as a polymeric matrix to create a novel membrane. Employing a film casting technique, we incorporated varying ratios of biological nanoparticles—Hydroxyapatite (HAP) and Cerium Vanadate (Ce₃(VO₄)₄)—to improve the wound dressing's properties. Wettability assessments provided insights into the surface characteristics of the scaffolds, revealing a diverse range of contact angles that reflect varying hydrophilic properties. Notably, the pure PVA/HA sample exhibited a contact angle of approximately 31.2° ± 12.1°, indicating excellent hydrophilicity and a strong capacity for drug absorption. However, the doping of nanoparticles resulted in an raise in contact angles, suggesting a slight reduction in hydrophilicity. Specifically, the addition of HAP produced a contact angle of about 36.5° ± 6.7°, while the addition of Ce₃(VO₄)₄ resulted in a contact angle of approximately 38.6° ± 6.4°. A significant increase in contact angle to 42.23° ± 4.8° was observed when mixing the nanoparticles, though the introduction of Graphene Oxide (GO) reduced the angle to 37.4° ± 0.35°, enhancing the hydrophilic properties of the composite. Cell viability testing was conducted to confirm the biocompatibility and bioactivity of the fabricated scaffolds. The results confirmed the ability of the scaffolds to promote cell growth, with an increase of 88.4 % in cell growth ratio observed at a suitable drug concentration of approximately 0.68 μg/ml. These findings highlight the potential of the developed scaffolds to enhance the wound healing process.

Electron beam induced graft polymerized anti oil-fouling biaxial polypropylene membrane with harsh environment tolerance

The intrinsic hydrophobic behavior of biaxial-oriented polypropylene microporous membrane limits its broad application area by leading serious membrane fouling. An environment-friendly, practical, and facile to large-scale prepared surface modification process is designed to enhance the membrane wettability and oil-fouling. By employing electron beam radiation, acrylic acid, and polyvinyl alcohol in the pre-irradiation-induced graft polymerization process, a micro-nano structure was developed and the surface roughness was increased from 66.5 nm to 99.3 nm. Enhancing the grafting ratio further reduces the pore size of the final modified membrane from 54 nm to 25 nm, which is significantly smaller than the size of the emulsified oil droplet. By modifying the morphological and structural characteristics of the grafted membrane, excellent oil-fouling resistance features are attained with UWOCA value 161° and separation efficiency of 99.3 %. Moreover, the theoretical explanations for hydrophilicity and oil-fouling resistance of modified membranes are also developed using DFT calculations and the Hermia model, which shows alignment with experimental data. Consequently, considerable improvements in wettability, thermal and mechanical behavior are obtained by this facial surface modification approach, which could further broaden the modified membrane's applications area in membrane separation technology while lengthening its service life.

Microbial dynamics, chemical profile, and bioactive potential of diverse Egyptian marine environments from archaeological wood to soda lake

Halophilic archaea are a unique group of microorganisms that thrive in high–salt environments, exhibiting remarkable adaptations to survive extreme conditions. Archaeological wood and El–Hamra Lake serve as a substrate for a diverse range of microorganisms, including archaea, although the exact role of archaea in archaeological wood biodeterioration remains unclear. The morphological and chemical characterizations of archaeological wood were evaluated using FTIR, SEM, and EDX. The degradation of polysaccharides was identified in Fourier transform infrared analysis (FTIR). The degradation of wood was observed through scanning electron microscopy (SEM). The energy dispersive X–ray spectroscopy (EDX) revealed the inclusion of minerals, such as calcium, silicon, iron, and sulfur, into archaeological wood structure during burial and subsequent interaction with the surrounding environment. Archaea may also be associated with detected silica in archaeological wood since several organosilicon compounds have been found in the crude extracts of archaeal cells. Archaeal species were isolated from water and sediment samples from various sites in El–Hamra Lake and identified as Natronococcus sp. strain WNHS2, Natrialba hulunbeirensisstrain WNHS14, Natrialba chahannaoensis strain WNHS9, and Natronococcus occultus strain WNHS5. Additionally, three archaeal isolates were obtained from archaeological wood samples and identified as Natrialba chahannaoensisstrain W15, Natrialba chahannaoensisstrain W22, and Natrialba chahannaoensisstrain W24. These archaeal isolates exhibited haloalkaliphilic characteristics since they could thrive in environments with high salinity and alkalinity. Crude extracts of archaeal cells were analyzed for the organic compounds using gas chromatography–mass spectrometry (GC–MS). A total of 59 compounds were identified, including free saturated and unsaturated fatty acids, saturated fatty acid esters, ethyl and methyl esters of unsaturated fatty acids, glycerides, phthalic acid esters, organosiloxane, terpene, alkane, alcohol, ketone, aldehyde, ester, ether, and aromatic compounds. Several organic compounds exhibited promising biological activities. FTIR spectroscopy revealed the presence of various functional groups, such as hydroxyl, carboxylate, siloxane, trimethylsilyl, and long acyl chains in the archaeal extracts. Furthermore, the archaeal extracts exhibited antioxidant effects. This study demonstrates the potential of archaeal extracts as a valuable source of bioactive compounds with pharmaceutical and biomedical applications.

Relationship between dietary oxidative balance score, anthropometric measurements and socioeconomic factors in women at low risk of cardiovascular disease

IntroductionThe aim of this study was to investigate the relationship between the dietary oxidative balance score (OBS), an indicator of oxidative stress, anthropometric measures and socioeconomic factors in women at low risk of cardiovascular disease. MethodsThe participants’ 3-day dietary intake, demographic information, anthropometric measurements and blood pressure values were recorded, and the Framingham Risk Score (FRS) and OBS values were determined. Oxidative balance score consists of prooxidant and antioxidant scores. Prooxidant scores were calculated from red meat consumption, total iron and polyunsaturated fatty acid intake, alcohol and cigarette consumption parameters, while antioxidant scores were calculated by assessing cruciferous consumption, dietary total vitamin C, vitamin E, β-carotene, β-cryptoxanthin, β-carotene, β-cryptoxanthin, lycopene, lutein+zeaxanthin and selenium intake. ResultsA total of 145 women were included in the study. Education level was associated with anthropometric measurements, income status with antioxidant and prooxidant scores, and exercise status with OBS (p<0.05). Weight, waist, hip, BMI, waist/hip, and waist/height ratio were significantly lower in subjects with low prooxidant score (p<0.05); there was no significant relationship between age, systolic, diastolic, FRS (p>0.05). ConclusionThe study, conducted in healthy women, showed that dietary oxidative balance scoring is promising in preventing the development of CVD and reducing the burden of disease, and that prospective cohort studies should be conducted in this area.

Biocompatible Quince Seed Mucilage Hydrogel: A Versatile Platform for Efficient Drug Delivery of Ceftriaxone with Enhanced Adsorption Properties

AbstractThe objective of this study was to explore the applicability of biocompatible quince seed mucilage hydrogel as a promising material for drug delivery systems. In this investigation, the hydrogel was synthesized through the graft copolymerization of acrylic acid and allyl polyvinyl alcohol onto quince seed mucilage in an aqueous solution under an argon atmosphere. Characterization of the synthesized hydrogel was performed using Fourier‐transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FE‐SEM), and thermogravimetric analysis (TGA). Subsequently, the developed hydrogel served as a carrier for ceftriaxone antibiotic release in both distilled water and a buffer solution with a pH of 7.4. The results demonstrated an impressive encapsulation efficiency of 96.1% for ceftriaxone within the hydrogel matrix. Additionally, the adsorption properties of ceftriaxone onto the proposed hydrogel structures (I, II, and III) were theoretically investigated in the aqueous phase using Monte Carlo adsorption locator calculations in Materials Studio2017. Our findings revealed strong adsorption on structure (III) compared to structures (I and II), with respective theoretical energies of −2.836 kcal/mol, −2.840 kcal/mol, and −2.127 kcal/mol. Therefore, the proposed hydrogel structure (III) emerges as a promising candidate for drug delivery applications, emphasizing its potential as an efficient carrier system.

Synthesis of plantain peel powder-based biofilm

The present study investigated the use of ripe plantain peel powder, crude glycerol, vinegar, egg shell powder and cassava starch as source raw materials for producing plantain peel-based biodegradable biofilm (P-BF). The synthesized biofilm was characterized by chemical test (FTIR, GC-MS, morphology test, water absorption property, biodegradation test, solubility test and swelling test) and mechanical test (ultimate tensile test, flexural, hardness test, % elongation and thermogravimetric analysis). Results showed successful production of P-BF. A non-plantain bioplastic (NP-BF) served as control. The FTIR analysis showed eight functional groups; ether, ethene, amine, carboxylic acid, nitriles, methylene, cyclic ester, primary, secondary and tertiary alcohols common to hydrocarbons. The biodegradation test showed the P-BF degraded at the same pace as NP-BF which degraded on the 6th day of the test. The mechanical test showed P-BF had higher thermal stability and water absorption property compared to the NP-BF. However, P-BF showed lower ultimate tensile test, flexural, hardness test, percentage elongation compared to the NP-BF. Morphology test showed that there was uneven distribution of constituents materials in P-BF compared to the NP-BF which affected its mechanical properties. In conclusion, the study successfully produced plantain peel-based biodegradable biofilm with good mechanical properties, biodegradability, thermal stability, fair water absorption property.

Synthesis, characterization and photoelectrochemical performance of Bi2Fe4O9 thin films

Mullite-type Bi2Fe4O9 has been little explored in thin film form as a photoanode for photoelectrochemical water splitting. In this study, Bi2Fe4O9 thin films have been prepared using the sol-gel technique from a simple precursor solution based on the corresponding metal salts, acetic acid, and polyvinyl alcohol. The films were deposited by dip-coating onto fluorine-doped tin oxide substrates and dried at 350 °C, repeating the dipping-drying cycle six times, and finally sintered at 600 °C. The films were characterized by GIXRD, revealing the formation of the material in its orthorhombic phase. Raman spectroscopy showed the Ag and B1g vibrational modes, validating the formation of the bismuth iron oxide. UV–Vis transmittance measurements revealed that the material exhibits two optical transitions: a direct band gap of 2.86 eV and an indirect band gap of 1.98 eV. FESEM micrographs and AFM images showed a uniform nanostructured surface morphology. The photoelectrochemical properties of the Bi2Fe4O9 films were studied using cyclic voltammetry and chronoamperometry with front side illumination, demonstrating the stability of the material in aqueous media and the generation of photocurrent in the presence of H2O2. Furthermore, results from intensity-modulated photocurrent spectroscopy (IMPS) revealed that the photocurrent is limited by both bulk and surface recombination and a short hole diffusion length.

Testing sample selection criteria and loss of biomarkers during cleaning of archaeological unglazed pottery to maximize organic residue quantities

AbstractAs the number of studies in organic residue analysis (ORA) of ancient pottery—a sensitive but as of today also a destructive method—increases, archaeologists are interested in knowing which samples promise the biggest abundance of analytes in order to avoid unnecessary loss of artefacts. Another frequently asked question is whether the routinely performed cleaning procedure should be omitted for samples intended for ORA to preserve the availability of analytes. We tested several selection criteria commonly accessible to archaeologists (texture, position, shape) for lipid quantities in ancient pottery in order to determine the most productive sherds for analysis. Moreover, we monitored loss of lipids during the water‐and‐brush cleaning process. Beside the usually targeted straight‐chain fatty acids (FA), less abundant biomarkers such as α,ω‐dicarboxylic acids (DCA), ω‐(o‐alkylphenyl)alkanoic acids (APAA) and hydroxy fatty acids (HFA) were also screened. The highest concentrations of analytes were observed in rims of coarse‐textured plates and cooking pots, demonstrating the usefulness of the proposed criteria. The washing procedure applied here did not lead to a loss of bulk FA, although the effect on minor components was not uniform.

Sustainable synthesis of 2-ethyl hexyl oleate via lipase-catalyzed esterification: A holistic simulation and cost analysis study

Lipase catalyzed synthesis of fatty acid esters has recently attracted much attention as it represents a cleaner production route compared to the conventional energy intensive chemical method. In this study, the technical and economic viability of 2-ethyl hexyl oleate (2-EHO) synthesis by the catalytic esterification of oleic acid (OA) and 2-ethyl hexyl alcohol (2-EHA) in a stirred tank reactor using Novozym 435 (Candida antarctica lipase B) was investigated. A conversion rate of 91% was obtained by adopting the subsequent optimized parameters: 4% enzyme amount, 2 h reaction time, 4:1 M ratio of alcohol to fatty acid, 150 rpm stirring speed, and 60 °C temperature. The lipase operational stability study showed that enzymes can be used for 30 successive cycles without significant lose in activity. The use of Aspen Plus simulator enabled the development of a detailed process flow diagram, which significantly improved the understanding of this clean production method and assessed the overall costs. A holistic cost analysis revealed a production cost of $2109 per ton of 2-EHO, thereby yielding an approximate 28% profit margin relative to prevailing market rates. Rigorous financial assessments corroborated the project's viability, substantiating a net present value (NPV) of $14.7 MM, a return on investment (ROI) of 583.91% (plant life time = 15 years), projected Payback Period stands at 6 years, and an internal rate of return (IRR) of 23%. These results confirm the technical and economic feasibility of lipase catalyzed production of 2-EHO, highlighting its potential as an environmentally and profitable approach in the synthesis of fatty acid esters.

Citric Acid and Polyvinyl Alcohol Induced PEDOT: PSS with Enhanced Electrical Conductivity and Stretchability for Eco-Friendly, Self-Healable, Wearable Organic Thermoelectrics.

Poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT: PSS) is a promising material for organic thermoelectric (TE) applications. However, it is challenging to achieve PEDOT: PSS composites with stretchable, self-healable, and high TE performance. Furthermore, some existing self-healing TE materials employ toxic reagents, posing risks to human health and the environment. In this study, a novel intrinsically self-healable and wearable composite is developed by incorporating environmentally friendly, highly biocompatible, and biodegradable materials of polyvinyl alcohol (PVA) and citric acid (CA) into PEDOT: PSS. This results in the formation of double hydrogen bonding networks among CA, PVA, and PEDOT: PSS, inducing microstructure alignment and leading to simultaneous enhancements in both TE performance and stretchability. The resulting composites exhibit a high electrical conductivity and power factor of 259.3 ± 11.7 S·cm-1, 6.9 ± 0.4 µW·m-1·K-2, along with a tensile strain up to 68%. Furthermore, the composites display impressive self-healing ability, with 84% recovery in electrical conductivity and an 85% recovery in tensile strain. Additionally, the temperature and strain sensors based on the PEDOT: PSS/PVA/CA are prepared, which exhibit high resolution suitable for human-machine interaction and wearable devices. This work provides a reliable and robust solution for the development of environmentally friendly, self-healing and wearable TE thermoelectrics.