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The influence of oxidation state and crystalline structure on the dissolution mechanisms of both pure iron oxides and combusted iron particles in aqueous oxalic acid (0.5 mol/l) at 60 °C was systematically investigated. Dissolution experiments were carried out in a temperature-controlled, continuous-flow capillary reactor, allowing for the removal of reaction products and thereby suppressing the autocatalytic reaction mechanism. The non-reductive dissolution of α-Fe2O3 was observed through in situ x-ray absorption measurements. In contrast, the dissolution of spinel-type oxides such as γ-Fe2O3 and Fe3O4 proceeded reductively, indicated by gradual changes in characteristic spectral features. Given that γ-Fe2O3 and Fe3O4 share a similar crystal structure but differ in the nominal oxidation state, this implies that the phase composition is decisive for the reductive dissolution. For mixed-phase particles consisting of spinel and rhombohedral phases (maghemite and hematite), the preferential dissolution of the spinel phase was observed. Despite the similar bulk composition of spinel and rhombohedral phases in the combusted iron particles (as confirmed by Mössbauer spectroscopy and x-ray diffraction analysis), dissolution predominantly follows a non-reductive pathway, with no preferential dissolution of the γ-phase. This unique dissolution behavior of combusted iron particles arises from their layered microstructure. [ABSTRACT FROM AUTHOR]

The glass formation and the dipolar reorientational motions in deep eutectic solvents (DESs) are frequently overlooked, despite their crucial role in defining the room-temperature physiochemical properties. To understand the effects of these dynamics on the ionic conductivity and their relation to the mechanical properties of the DES, we conducted broadband dielectric and rheological spectroscopy over a wide temperature range on three well-established carboxylic acid-based natural DESs. These are the eutectic mixtures of choline chloride with oxalic acid (oxaline), malonic acid (maline), and phenylacetic acid (phenylaceline). In all three DESs, we observe signs of a glass transition in the temperature dependence of their dipolar reorientational and structural dynamics, as well as varying degrees of motional decoupling between the different observed dynamics. Maline and oxaline display a breaking of the Walden rule near the glass-transition temperature, while the relation between the dc conductivity and dipolar relaxation time in both maline and phenylaceline is best described by a power law. The glass-forming properties of the investigated systems not only govern the orientational dipolar motions and rheological properties, which are of interest from a fundamental point of view, but they also affect the dc conductivity, even at room temperature, which is of high technical relevance. [ABSTRACT FROM AUTHOR]

The extraction of organic pollutants from environmental samples using green solvents has received a lot of interest recently. Simply said, this is due to their extremely low toxicity and volatility when compared to the common organic solvents. Therefore, many extraction exercises now include ionic solvents, as well as the more current deep eutectic solvents (DES). Hence, the current study reports on 1) the synthesis and characterisation of choline chloride/oxalic acid (1:1) and choline chloride/urea (1:2) deep eutectic solvents and 2) their application in liquid-liquid and solid-liquid assisted extraction of 14 targeted OPFRs from landfill leachate and sediment samples. The densities, refractive indices and melting points of the DES measured were 1.11 ± 0.15 g/mL, 1.14 ± 0.10 g/mL; 1.50 ± 0.12, 1.45 ± 0.20; and 12 ± 0.05°C, 35 ± 0.06–55 ± 0.05°C for choline chloride/urea (1:2) and choline chloride/oxalic acid (1:1) respectively. Choline chloride/urea (1:2) and choline chloride/oxalic acid (1:1) viscosities were 87.0 ± 0.20 kg·m −1·s −1 and 13.5 ± 0.14 kg·m −1·s −1 respectively. 1H NMR and FTIR confirmed the structures of the two DES. Recoveries using internal standards dTPP, dTBP, dTPrP and 13C18MTPP ranged from 59.9 ± 7.41–103 ± 5.32%; whereas the percent recoveries using CRM ranged from 85.7–117%. In the leachate (510–1433 ng/L) and sediment (725–1224 ng/g dw) samples from each landfill, 14 and 13 targeted OPFRs, respectively, were detected. The high recoveries and extraction of OPFRs demonstrated by the two DES imply that these could replace conventional organic solvents used to extract OPFRs from environmental media. [ABSTRACT FROM AUTHOR]

Atenolol (ATL) is a cardioselective β1-receptor antagonist used to treat cardiovascular disorders such as hypertension and angina. It belongs to the biopharmaceutical classification system (BCS) class III, for which permeation across the intestinal membrane is the rate-limiting step. This study aims to screen biologically acceptable salts of ATL to improve its diffusion properties using six dicarboxylic acids such as oxalic acid (OXA), fumaric acid (FUM), malic acid (MAL), glutaric acid (GLU), adipic acid (ADP) and pimelic acid (PIM). The organic salts were subjected to solid-state characterization such as powder XRD, single crystal XRD, DSC/TGA, and FT-IR spectroscopy. The crystal structures confirm the proton transfer from the carboxylic acid to the isopropyl amine fraction of ATL. Among the multicomponent salts, ATL forms anhydrous salts with GLU/MAL, whereas ATL–OXA/FUM/ADP/PIM are confirmed to be salt hydrates. Similar to the native drug, all the salts maintained stability for more than 1 month during exposure to 35 ± 5 °C/75 ± 5% relative humidity conditions. In addition, the salts were thermally stable at 50 °C for an hour. The aqueous solubility and diffusion study of the ATL salts (ATL–ADP/FUM/PIM/GLU/MAL/OXA) in pH 6.8 phosphate buffer indicated improved solubility (up to 33-fold) and flux (up to 2.8-fold) compared to the native drug due to ionic interactions between the drug and the counterion. Improved diffusion properties of the ATL salts are partially correlated with their enhanced solubility distribution coefficients and log P of the salt former. [ABSTRACT FROM AUTHOR]

The review presents the main functions of oxalates (oxalic acid and its salts) in physiological processes in plants. The participation of endophytic bacteria, oxalotrophs and/or oxalic acid producers, in the regulation of plant responses to the effects of unfavorable environmental factors of biotic and abiotic nature is considered. A conclusion is made about the prospects for the development of a new direction in the study of the role of endophytic bacteria in the formation of oxalate-mediated adaptive potential in plants. [ABSTRACT FROM AUTHOR]

The objective of this ongoing research is to investigate and assess the aqueous extracts, vegetable oil, and residual plant components derived from O. dillenii by use of HPLC, and GC-MS. Subsequent investigations employed colorimetric techniques to identify reducing and soluble sugars. We developed and validated an energy-dispersive X-ray fluorescence (EDXRF) method for determining the concentrations of essential chemical elements (O, C, Ca, Mg, K, S, P) in seeds, juice, and peel, as well as their residues. HPLC analysis yielded results indicating that extracts from O. dillenii seeds, juice, and peel from distinct regions (Oujda, Nador, and Essaouira) contained elevated concentrations of metabolites. Specifically, peel and juice extracts exhibited the highest levels of organic acids and betanin compared to O. dillenii seeds. Conversely, seed oils displayed a noteworthy tocopherol content, predominantly δ-tocopherol. Similarly, an examination of organic acid composition in juice, peel, and seeds from three different regions revealed their elevated levels. Citric acid and oxalic acid emerged as predominant components in the juice. Overall, Opuntia dillenii's physicochemical and phytochemical characterization improves in understanding its potential as a bioactive chemical promoter, which could lead to the creation of new medicinal medicines or functional food ingredients. [ABSTRACT FROM AUTHOR]

Effective pretreatment is essential for successfully utilizing renewable resources such as lignocellulosic biomass in the production of bioethanol. In this study, ternary deep eutectic solvents (DESs), namely choline chloride/lactic acid/glycerol (ChCl/LA/Gly), choline chloride/oxalic acid/glycerol (ChCl/OA/Gly), choline chloride/lactic acid/ethylene glycol (ChCl/LA/EG), and choline chloride/oxalic acid/ethylene glycol (ChCl/OA/EG) were prepared and employed for the pretreatment of cellulose-rich Napier grass (NG). Post treatment, the NG hydrolysate was subjected to enzymatic saccharification followed by ethanol fermentation. The results showed effective delignification of NG after treatment with the prepared ternary DESs, with ChCl/LA/EG removing a maximum of 92.89% lignin. The efficiency of the prepared DESs is attributed to their low densities, pH, and viscosity. Enzymatic saccharification of ChCl/LA/EG-treated NG resulted in a 1.68 fold increase in reducing sugar yield compared to that of untreated NG. All pretreated NG produced more bioethanol via a separate hydrolysis and fermentation (SHF) process than untreated NG after Saccharomyces cerevisiae fermentation. A maximum of 0.37 g bioethanol/g of biomass was obtained from the one-pot process using ChCl/LA/Gly pretreatment. FTIR and XRD analyses of untreated and pretreated NG corroborated the efficacy of the ternary DESs on cellulose recovery and delignification. Also, enzymatic and microbial inhibition studies on the prepared DESs show their potential to be employed in a one-pot process for biorefinery. The results of the present investigation show the potential of utilizing eco-friendly DESs and renewable resources for the production of bioethanol, a viable option to fossil fuels. [ABSTRACT FROM AUTHOR]

Hexavalent chromium (Cr(VI)) has attracted great considerations due to their high toxicity, teratogenicity, and carcinogenicity. In this study, four Zr‐MOFs were synthesized and used to comparative study their catalytic performances of oxalic acid (OA) for Cr(VI) removal. Results showed that the removal efficiency for Cr(VI) was reached 65.91%, 78.64%, 53.58%, and 96.32% by MOF‐525, MOF‐525(Co), MOF‐525(Zn), and MOF‐525(Fe) in the presence of OA when the initial Cr(VI) concentration was 100 mg·L−1, respectively. The single‐factor experiments for further improving the Cr(VI) removal by MOF‐525(Fe)/OA demonstrated that the optimal conditions were OA dosage of 790 mg·L−1, and MOF‐525(Fe) dosage of 500 mg·L−1 and pH of 2.0, and the MOF‐525(Fe)/OA system could be used to treat Cr(VI)‐containing wastewater at concentrations below 50 mg·L−1. Ionic strength studies indicated that Na+, K+, Mg2+, Cl−, and SO42− had little effect on the catalytic reduction of Cr(VI), while high concentrations of Ca2+ (0.10 and 0.25 mol·L−1), NO3− (0.25 mol·L−1), and PO43− (0.25 mol·L−1) had significant inhibition effects. The reusability experiments showed that the stability of MOF‐525(Fe) was excellent, and it could be used for potential applications. Based on the results of Fourier transform infrared spectroscopy (FTIR), X‐ray photoelectron spectroscopy (XPS), and Electron Paramagnetic Resonance spectrometer (EPR), the possible reduction mechanism of Cr(VI) by MOF‐525(Fe)/OA system was proposed as follows: The complexation of OA with Fe3+ was first complexed to produce Fe2+ and CO2•−, then Cr(VI) was combined with Zr–O and Fe–O clusters in MOF‐525(Fe) to obtain activation energy, and the reduction ability was enhanced at the same time; finally, Cr(VI) obtained electrons from CO2•− and was sequentially reduced as Cr(V) and Cr(III). [ABSTRACT FROM AUTHOR]

The exploitation of deep-eutectic solvents (DESs) offered a potential substitute for water-based solutions when it came to leaching REEs from phosphogypsum (PG). The REEs leachate from PG obtained by DES which comprised choline chloride (ChCl) and diglycolic acid (DGA) or lactic acid (LA). The data offered a successful method for REEs leaching by DES ChCl:LA. The optimal leaching conditions included 150 min, 70°C, ChCl:LA 1:2 molar ratio of 800 rpm, a 15:1 L/S ratio, and 15% additional water. Cyanex 923 was used to assess REEs extraction from DES leachate. The best parameters were 900 rpm, 0.8 M Cyanex/toluene at 25°C, with 15 min extraction time and 1/1 A/O ratio. The REEs were stripped from the REEs/Cyanex after equilibrating for 20 minutes using 0.7 M citric acid, 1/2 A/O ratio, and 1000 rpm at 25°C. The RE ions precipitated from the obtained stripping solution by 30% oxalic acid and pH 1. The RE oxalate was precipitated and then burned at 700°C to gain RE oxide. The RE oxide powder was subjected to analysis to determine the REEs; it was possible to determine that the REEs were 80.98% in RE oxide concentrate, resulting in a purity of 94.76%. [ABSTRACT FROM AUTHOR]

The scientific community has become interested in cellulose extraction from agro-industrial wastes because they contain large quantities of cellulose and are being researched globally due to their application. Cellulose extracted from these wastes offers varying characteristics and structures depending on the specific source. In this study, microcrystalline cellulose (MCC) was extracted from different parts of the durian husk through acid hydrolysis with various concentrations of oxalic acid and cellulose-to-acid ratios. The durian husk underwent a pretreatment method involving bleaching and alkaline treatment. The characteristics of MCC, such as functional group, morphology, and crystallinity, were studied. The findings indicated that lignin was successfully removed through pretreatment. However, traces of hemicellulose were still detected in a few samples. The extracted MCCs demonstrated a diameter range from 6.237 to 25.38 μm and crystallinity within the range of 71.43–78.30%. Polycaprolactone (PCL)-based biocomposites with different MCC weights (0.2, 0.5, and 1.0 wt%) were fabricated, and the performance was evaluated through tensile testing and biodegradability tests. The addition of 1.0 wt% MCC enhanced the tensile strength by 22%. SEM analysis revealed the cross-section fracture surface of the biocomposite, indicating the contribution of the MCC during pull-out. Meanwhile, the biodegradability of the biocomposite increased with the addition of MCC, indicating that the MCC-based biocomposite was fully biodegradable. [ABSTRACT FROM AUTHOR]

Background: Post-harvest losses cause significant product losses in the world, which leads to food waste. Therefore, it is of great importance for people to have access to sufficient amounts of products by increasing the storage period of fruits with applications such as post-harvest calcium chloride (CaCl2). In this study, the effect of calcium chloride (CaCl2) on physical quality parameters and bioactive contents of stored strawberry fruit (Albion cv.) was investigated. Accordingly, strawberries were treated with 2%, 4% and 6% CaCl2 before storage and stored for 15 days (0 ± 0.5 °C and 90 ± 5% RH). Analyses and measurements were conducted every 5 days during the storage period.Weight loss, decay rate, soluble solids content (SSC), acidity, pH, respiration rate, organic acids (malic, citric, ascorbic, fumaric, oxalic, succinic and tartaric) and phenolic compounds (catechin, chlorogenic, ferulic, gallic, o-coumaric, p-coumaric, protocatechuic, quercetin, rutin and syringic) were analyzed as quality parameters during storage. Results: In the study, in general, the best values were observed in 6% CaCl2-treated fruits in terms of weight loss, SSC, TA, decay and respiration rates, although they varied according to different storage periods. Similarly, in terms of phenolic compounds, organic acids and vitamin C, 6% CaCl2-treated fruits had significantly better prevention of quality losses. In addition, the most common phenolic compound of strawberry fruits was gallic acid, followed by chlorogenic acid and catechin, respectively. On the other hand, the predominant organic acid observed in the fruits was malic acid, followed by citric acid, succinic acid and oxalic acid, respectively. Conclusions: In this study, it was observed that CaCl2 applications more effectively prevented weight loss and decay rate by reducing the respiration rate compared to the control group at the end of the storage period (15th day). It was concluded that, particularly, the 6% CaCl2 dose can be used as an important treatment to extend storage life by preserving fruit quality and biochemical changes. [ABSTRACT FROM AUTHOR]

Cotton textiles play a universal role in everyday life, but they are prone to stain and serve as a primary channel for transmitting viruses and bacteria. The photocatalytic/antibacterial coatings are highly effective in addressing bacterial contamination on fabrics, although their efficacy diminishes with continuous use and washing. Here, insights are provided into the attachment of LiNbO 3 on cotton surfaces using eco-friendly chemical activators to promote resistance to washing cycles, self-cleaning, and bactericide textiles. LiNbO 3 nanoparticles were synthesized by low-temperature hydrothermal synthesis and directly applied to cotton fabric using immersion. The synthesized nanoparticles were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) N 2 adsorption, diffuse reflectance for band gap determination, and Raman spectroscopy. A simple and effective impregnation method was used, promoting an ester-bond attachment between the cotton surface and the activators. Microscopy analysis (SEM) confirmed the successful deposition of the nanoparticles on cotton fabric. The LiNbO 3 coating consisted of transparent layers and did not change the properties of cotton. Methylene blue stains are generally eliminated under UV light after 2 h using nanoparticles and activators. Antibacterial properties were evaluated under visible light through direct contact with bacterial suspensions and culturing. The coated cotton fabric that was activated with oxalic acid exhibited significant photocatalytic antibacterial activity against both Escherichia coli (gram-negative) and Staphylococcus aureus (gram-positive) bacteria, with bacterial reduction rate above 97 %, even after 10 washing cycles. This performance can be attributed to the effective coupling of LiNbO 3 with oxalic acid in the cotton's surface and its resistance to washing out. This study's novel synthesis and coating method offers an environmentally friendly, cost-effective, and straightforward approach for producing LiNbO 3 self-cleaning and antibacterial surface-activated cotton. [ABSTRACT FROM AUTHOR]

Background: Dentin hypersensitivity (DH) affects many patients. Various therapeutic options have been devised to alleviate this condition by achieving dentinal tubules (DT) occlusion. This research aimed to investigate the effects of dipotassium oxalate-containing mouthwash, diode laser and their combination on DT occlusion. Methods: Forty dentin samples were obtained from 20 human single-rooted third molars, 40 dentin specimens were obtained, and exposed DT were created in vitro. They were assigned into four groups: Group 1 (n = 10), the control group where no treatment was applied; Group 2 (n = 10), a mouthwash with a 1.4% dipotassium oxalate was applied twice for 60 s during a 5-day period in a shaker at 100 rpm; Group 3 (n = 10), a combination of the same mouthwash and an 810 nm diode laser at an output power of 0.25 W in continuous mode was applied for 60 s without contact at a distance of 3–4 mm; and Group 4 (n = 10), only a diode laser with the same protocol was applied. Occlusion of the DT was observed by scanning electron microscopy. Results: The analysis revealed occlusion of the DT in all treatment groups; however, the effects were more pronounced in the combined treatment group (Group 3). Compared with the test groups, the control group had significantly more open DT in 100 µm2 (p < 0.01). The difference between the Group 2 and Group 4 was not significant (p > 0.05). Conclusion: DT occlusion was achieved via the use of a mouthwash containing 1.4% dipotassium oxalate and an 810 nm diode laser. However, the combination resulted in the greatest results and therefore may be utilized in individuals with DH. [ABSTRACT FROM AUTHOR]

In the present research, it is reported that ball milling technique can be applied to enhance the photocatalytic properties of MnO and ZrO 2 metal oxide powders (MZOx) furthermore the fabricated photocatalyst can be used for the degradation of tetracycline (TTC). XRD analyses revealed that increasing the milling time resulted in the formation of a pure metallic Mn crystal phase, which boosted the antibiotic degradation rate. It was confirmed by SEM technique that the morphological structures of the particles were generally small and uniform. The band gap energy was calculated as 3.70 eV for the hybrid metal oxide. Additionally, the adsorptive and photoluminescence features were illuminated via DRS and PL analyses. The effect of milling time had a major impact on the photodegradation rate of TTC, and the 8 h milling sample (MZOx-8h) exhibited the highest catalytic degradation activity (79.4 %). Low photocatalytic activity was obtained at acidic pHs and increased at alkaline pHs. The presence of H 2 O 2 sharply decreased photocatalytic process time (60 min) and 94.3 % of the TTC was degraded at 7.5 mM H 2 O 2. The photocatalytic degradation process proceeded through superoxide radicals and was supported by holes. The stability of MZOx-8h almost remained constant (70.02 %) even after seven cycles. It was determined that the presence of oxalic acid positively affected the progress of TTC degradation reactions. Further, practical application areas were investigated and MZOx-8h doped on support materials was found to be suitable for such applications in proportion to the doping ratio. Finally, it was demonstrated that MZOx-8h exhibited remarkable performance in photocatalytic reactions of different types of organic pollutants. The synergistic nature of MnO and ZrO 2 with the contribution of ball milling time effect resulted in high photocatalytic activity. • High purity metallic Mn phase was successfully synthesized by ball-milling. • MZOx was used for the first time in TTC photodegradation. • TTC degradation was stable in the seventh cycle. • The different organic pollutants were removed with high efficiency. [ABSTRACT FROM AUTHOR]

Oxalic acid is one of the important acids that is used in many fields. It is of medical, industrial and agricultural importance and is used as an acid in foods, building and construction, pharmacy, and others. This acid is produced in multiple ways, and the biogenic method is the best method because it is safe and cheap. Hence, this study came about, where reliance was placed on wheat bran in preparing nutrient medium to produce oxalic acid from Candida albicans and Aspergillus niger yeast isolated from environmental and pathogenic sources. The study aimed to use wheat bran as an alternative medium for growing fungi and yeasts that produce oxalic acid, and to compare the productivity of this medium with standard media. One hundred fungal isolates were isolated from different environmental and clinical sources, and grown in Sabouraud dextrose agar medium (SDA) and potato dextrose agar to obtain pure isolates of A. niger and C. albicans. Thirty seven isolates of C. albicans and thirty two isolates of A. niger were isolated. Thirty one contaminated samples were discarded. The isolates were grown in standard (SDB, PDB) and alternative (wheat bran) media. The amount of acid was estimated by mulching against potassium permanganate. The results showed that wheat bran medium was the most efficient in producing oxalic acid with a rate of 26.2% for A. niger and 25.3% for C. albicans, compared to standard media. The best temperature for acid production was 32 °C with a production rate of 19.1% for A. niger and 22.7% for C. albicans. The best pH was 6.5 for A. niger with a production rate of 20.2% and 5.5 for C. albicans with a production rate of 23.3%. The study conclude from the above that the fungus A. niger is the best compared to C. albicans, as well as the medium of wheat bran is a promising and effective medium in the production of oxalic acid in an environmentally friendly way. [ABSTRACT FROM AUTHOR]

The physiochemical pretreatment was performed using different concentrations of oxalic acid (OA) as a simultaneous pretreatment and saccharification (SPS) process on rice straw to obtain reducing sugar from two‐phasic SPS process using enzymatic and acidic hydrolysis to subsequently ferment to bioethanol in order to maximize the yield of bioethanol. The optimal condition for pretreating rice straw using 0.5, 0.75, 1, and 1.5 M OA at 120°C for 1 h was evaluated. The morphological and structural changes after simultaneous pretreatment and SPS process were evaluated using Fourier‐transform infrared (FTIR), thermogravimetric analysis (TGA), X‐ray diffraction (XRD), and field‐emission scanning electron microscopy (FESEM) analysis. It was evaluated that optimum pretreatment conditions using a lesser concentration of OA had resulted in 30.37% of xylan removal from pretreated rice straw obtained after simultaneous pretreatment and SPS process. The ethanol production yield ranged from 0.42 to 0.37 g/g with fermentation efficiency of up to 57.18% and an overall ethanol production yield of 42.84% from the obtained hydrolysate of the two‐phasic SPS process. The highest ethanol concentration from the obtained hydrolysate was produced at 120°C for 1 h with 0.75 M OA; under this condition, maximum degradation of utilized lignocellulosic biomass takes place. [ABSTRACT FROM AUTHOR]

Background: Stem rot, caused by the soil-borne pathogen Sclerotium rolfsii, pose a serious challenge in the groundnut (Arachis hypogaea L) cultivation. Although this disease is widespread globally but had most adverse impact in groundnut growing regions of United States, India, and Australia. The pathogen primarily targets the crown region of the plant, resulting in systemic collapse and potentially leading to yield losses up to 80%. Effective genetic control measures are essential to mitigate the impact of this disease on groundnut production. Realizing the time and resource-consuming complex field-based phenotyping, the availability of easy and repeatable phenotyping methods may fasten the process of donor and gene discovery efforts. Results: Multi-season phenotyping was performed for stem rot on 184 minicore germplasm accessions, including checks, under two conditions: sick field screening and response to oxalic acid assay. This study demonstrated medium to high heritability (52–63% broad-sense heritability) and significant environmental influence (36%). The response to the oxalic acid assay showed a high proportion of similarity (approximately 80%) with the percent mortality observed in the sick field indicating an easy way of performing precise phenotyping. Notably, seven genotypes—ICG163, ICG721, ICG10479, ICG875, ICG11457, ICG111, and ICG2857—exhibited stable resistance, with less than 30% mortality against stem rot disease. Among these, ICG163, ICG875, and ICG111 displayed low mortality and consistent stability across multiple seasons in both the sick field and controlled conditions of the oxalic acid assay. Conclusions: The oxalic acid assay developed in this study effectively complements field phenotyping, as a reliable method for assessing stem rot resistance. Seven resistant genotypes identified through this assay can be utilized for the introgression of stem rot resistance into elite genotypes. Given the significant influence of the environment on stem rot resistance, it is essential to implement multi-season phenotyping to obtain precise results. Furthermore, the response to oxalic acid serves as a valuable supplement to traditional field phenotyping, since maintaining uniform disease pressure during field screenings is often challenging. [ABSTRACT FROM AUTHOR]

Cocrystals are assemblies of more than one type of molecule stabilized through noncovalent interactions. They are promising materials for improved drug formulation in which the stability, solubility, or biocompatibility of the active pharmaceutical ingredient (API) is improved by including a coformer. In this work, a range of density functional theory (DFT) and density functional tight binding (DFTB) models are systematically compared for their ability to predict the lattice enthalpy of a broad range of existing pharmaceutically relevant cocrystals. These range from cocrystals containing model compounds 4,4′‐bipyridine and oxalic acid to those with the well benchmarked APIs of aspirin and paracetamol, all tested with a large set of alternative coformers. For simple cocrystals, there is a general consensus in lattice enthalpy calculated by the different DFT models. For the cocrystals with API coformers the cocrystals, enthalpy predictions depend strongly on the DFT model. The significantly lighter DFTB models predict unrealistic values of lattice enthalpy even for simple cocrystals. [ABSTRACT FROM AUTHOR]

A multimode fiber-based sensor is proposed and demonstrated for the detection of lead traces in contaminated water. The sensing mechanism involves using a light sheet to excite a specific group of skew rays that optimizes light absorption. The sensing region features an inline microbubble structure that funnels the skew rays into a tight ring, thereby intensifying the evanescent field. The sensitivity is further refined by incorporating gold nanoparticles, which amplify the evanescent field strength through localized surface plasmon resonance. The gold nanoparticles are functionalized with oxalic acid to improve specificity for lead ion detection. Experiment results demonstrated the significantly enhanced absorption sensitivity of the proposed sensing method for large center offsets, achieving a detection limit of 0.1305 ng/mL (the World Health Organization safety limit is 10 ng/mL) for concentrations ranging from 0.1 to 10 ng/mL. [ABSTRACT FROM AUTHOR]

Purpose: As a commonly engine coolant, ethylene glycol can produce corrosive acid byproducts at high temperatures when the car is running, specifically oxalic acid (OA), which can shorten the service life of engine. At the same time, chloride ions can also be introduced during coolant preparation processes. Therefore, this paper aims to investigate the synergistic corrosion behavior of Cl− and OA on ADC12 aluminum alloy. Design/methodology/approach: The electrochemical tests, scanning electron microscopy, energy dispersive spectrometer, X-ray diffraction and X-ray photoelectron spectroscopy) were used. Findings: The results showed that the corrosion rate of the aluminum alloy increased with the increase of OA and Cl− concentrations. After adding Cl−, the surface film of the aluminum alloy was further damaged, Cl− has a synergistic effect with OA and their interaction further accelerated the corrosion of the aluminum alloy. Nevertheless, as the immersion time increased, the corrosion rate of the aluminum alloy gradually diminished due to the formation of aluminum oxalate. Originality/value: The corrosion of ADC12 aluminum alloy was studied in OA, Cl− and their mixed solutions; the synergistic effect of OA and Cl− on the corrosion of ADC12 aluminum alloy was discussed, and aluminum oxalate formed inhibited its corrosion. [ABSTRACT FROM AUTHOR]

Soybean molasses (SM), a sugar-rich by-product obtained from manufacturing soy protein concentrate, is an interesting source of fermentable sugars for biotechnological processes. For the first time, SM was used as a new and low-cost substrate in Aspergillus niger cultures to produce gluconic acid (GA), a carboxylic acid obtained by the oxidation of glucose and with a wide range of applications. The effect of SM composition and sugar content on GA batch production was studied in a stirred-tank bioreactor using two SM samples with different total sugar concentrations of 46 % and 52 % (w/w) and different sugar profiles. GA productivity improved as the total sugar concentration increased, whereas yield was unaffected. Agitation rate increase positively affected yield and productivity in SM medium with the highest sugar concentration. Under these conditions, the highest GA titer (79 g·L−1) was obtained. Oxalic acid and fructose syrup were other added-value compounds found from the submerged fermentation of SM. This work proved the potential of A. niger in the bioconversion of SM with different compositions into GA, providing a novel strategy for low-cost and eco-friendly GA production from SM. [Display omitted] • Soybean molasses is a new substrate for gluconic acid production by A. niger. • The sugar profile of soybean molasses affects organic acids production • Rise of agitation rate had positive effect on gluconic acid yield and productivity. • The highest titer (79 g·L−1) was obtained at 600 rpm and high sugar concentration. • Oxalic acid and high-fructose syrup were also produced from soybean molasses. [ABSTRACT FROM AUTHOR]

We explored the potential value of the alcohol dehydrogenase (ADH) inhibitor isovaleramide (ISO) in the treatment of acute ethylene glycol (EG) poisoning‐induced acute kidney injury. Sprague–Dawley rats were divided into the control, EG, EG + ISO (10 mg/kg) and EG + ISO (20 mg/kg) groups. It is found that ISO intervention significantly reduced the ADH activity in liver tissue by using visible spectrophotometry, inhibited the in vivo metabolism of EG by using gas chromatography, lowered the levels of toxic metabolites glycolic acid and oxalic acid by using high‐performance liquid chromatography and decreased the expression of kidney injury markers serum creatinine (sCr), KIM‐1, neutrophil gelatinase‐associated lipocalin (NGAL) and liver fatty acid‐binding protein (L‐FABP) by ELISA. Additionally, Western blotting results showed that ISO down‐regulated the expression of apoptotic factors Bax and cleaved caspase‐3 in the kidneys and upregulated the expression of antiapoptotic factor Bcl‐2. Pizzolato staining and polarized light microscopy results revealed the reduced deposition of calcium oxalate crystals in the kidney tubules. Using haematoxylin and eosin (H&E), periodic acid‐Schiff (PAS) and Masson staining, we found attenuated kidney tissue pathological injury. Finally, ISO significantly reduced the mortality rate. In conclusion, ISO has the potential to be a valuable drug for the treatment of EG poisoning‐induced acute kidney injury. [ABSTRACT FROM AUTHOR]

Fusarium verticillioides is both an endophyte and pathogen of maize. During growth on maize, the fungus often synthesizes the mycotoxins fumonisins, which have been linked to a variety of diseases, including cancer in some animals. How F. verticillioides responds to other fungi, such as Fusarium proliferatum , Aspergillus flavus , Aspergillus niger , and Penicillium oxalicum , that coinfect maize, has potential to impact mycotoxin synthesis and disease. We hypothesize that low molecular weight acids produced by these fungi play a role in communication between the fungi in planta/nature. To address this hypothesis, we exposed 48-h maize kernel cultures of F. verticillioides to oxalic acid, citric acid, fusaric acid, or kojic acid and then compared transcriptomes after 30 min and 6 h. Transcription of some genes were affected by multiple chemicals and others were affected by only one chemical. The most significant positive response was observed after exposure to fusaric acid which resulted in >2-fold upregulation of 225 genes, including genes involved in fusaric acid synthesis. Exposure of cultures to the other three chemicals increased expression of only 3–15 genes. The predicted function and frequent co-localization of three sets of genes support a role in protecting the fungus from the chemical or a role in catabolism. These unique transcriptional responses support our hypothesis that these chemicals can act as signaling molecules. Studies with gene deletion mutants will further indicate if the initial transcriptional response to the chemicals benefit F. verticillioides. • Low-molecular-weight fungal acids impact the Fusarium verticillioides transcriptome. • Fusaric acid impacted more genes than other acids. • Kojic acid impacted two gene clusters that occur widely in Fusarium. [ABSTRACT FROM AUTHOR]

Textile dyeing releases over 80% of industrial effluents without proper treatment. Dye discharged into effluents typically needs degradation before release into aquatic environments. In this regard, the present paper reports the nanocomposite copper oxide/polyaniline (CuO/PANI) is successfully synthesized by in situ chemical oxidative polymerization method and investigates their catalytic activity against organic dyes and nitro compounds. CuO is synthesized by colloidal sol–gel method using oxalic acid as capping agent to obtained desired morphology. The elemental composition, unit cell and lattice parameters of nanocomposite are characterized by using XRD. The XRD revealed that nanoparticles are extremely crystalline, but nanocomposite is amorphous because of the presence of polymer. The structural and elemental analysis of CuO and CuO/PANI is confirmed by SEM and EDX analysis. FTIR spectra of CuO showed bending vibration, while CuO/PANI showed the presence of benzenoid and quinoid rings. Catalytic productivity of the CuO and CuO/PANI as catalysts in degradation of dyes and reduction of nitro compounds is also studied. The degradation and reduction processes are monitored through the utilization of UV–Vis spectrophotometer. The catalytic activity of both catalysts is evaluated by several parameters including kapp, degradation/reduction time, % degradation/reduction, degraded/reduced concentration and half-life. Among all substrates, highest kapp is 0.0653 min−1 for CV by CuO, while 0.0502 min−1 for EBT by CuO/PANI due to large surface area. On degradation and reduction rate of substrates, the impact of functional group type and orientation, bond type and steric hindrance is also investigated. [ABSTRACT FROM AUTHOR]

Cerasus humilis fruit is known for its high acidity, surpassing that of most other fruits. The metabolism of organic acids in these fruits significantly influences sugar and calcium accumulation. However, research on this metabolic process is limited. This study investigates the organic acid metabolism and the accumulation patterns of sugars and calcium during the development of Cerasus humilis fruits. Using low−acid and high−acid varieties from Inner Mongolia, we compared organic acid components and the activity of relevant metabolic enzymes during fruit maturation. We also measured the content and proportions of various sugars and calcium forms, performing correlation analyses. Throughout the development and ripening of Cerasus humilis fruits, organic acids, sugars, and calcium exhibited consistent patterns of change across the two acidity types. Malic acid emerged as the most significant organic acid, while fructose was the primary sugar, and active calcium was the dominant calcium component. Correlation analyses indicated that malic acid and total acid positively correlated with sugar and water−soluble calcium content, negatively regulating other calcium forms. Conversely, NADP−ME, citric acid, and oxalic acid negatively correlated with sugars and water−soluble calcium, while positively affecting other calcium forms. In conclusion, the metabolism of organic acids during the development and maturation of Cerasus humilis fruits is closely linked to the accumulation of sugars and calcium. Malic acid, primarily regulated by NAD−MDH and NADP−ME, promotes the accumulation of sugars and water−soluble calcium but inhibits other calcium forms, while citric and oxalic acids inhibit sugar accumulation and promote non−water−soluble calcium forms. [ABSTRACT FROM AUTHOR]

Licorice roots can release low-molecular-weight oxalic acid (OA). However, the allelopathic effects of OA on licorice are unknown. This study presents an investigation of the effects of exogenous OA treatment on licorice roots through transcriptomic and physiological analyses. Transcriptomic analysis demonstrated that following OA treatment, differentially expressed genes (DEGs) were primarily involved in the phenylpropanoid metabolism pathway. At 6 h, the expression levels of genes associated with this pathway, such as PAL, CHS, POD, cellulase, CPY, MYB, and bHLH, were upregulated. The metabolism of related metabolites, such as flavonoids and lignin, also increased. These findings suggest that the phenylpropanoid metabolism pathway may play a significant role in the response to OA treatment. In addition, the activities of GST, CAT, and POD markedly increased, whereas the content of H2O2 gradually decreased, indicating that OA can activate the antioxidant protective capabilities of licorice roots. These findings suggest that OA may enhance the antioxidant defense of licorice root, as well as the effectiveness of its flavonoid constituents (to a certain degree). Our findings provide valuable theoretical insight into the allelopathic effects of licorice roots. [ABSTRACT FROM AUTHOR]

Objective: Complications from diabetic foot wounds, including bacterial infection, ulceration and gangrene, are major causes of hospitalisation and are responsible for 85% of amputations in patients with diabetes. Given that orally administered investigational therapeutic Cytoreg (Cytorex de Venezuela SA, Venezuela), a defined aqueous mixture of hydrofluoric, hydrochloric, sulfuric, phosphoric, citric and oxalic acids, has been shown to increase levels of arterial blood oxygen in a Wistar rat model, oral and oral+topical Cytoreg were tested on patients with diabetic foot ulcers (DFUs) under a humanitarian, compassionate-use protocol. Method: All patients received oral Cytoreg (5.0 ml concentrate in fruit juice) for 30 days; half also received weekly wound washing with Cytoreg concentrate in isotonic saline (1:50 volume/volume) (oral+topical group). In addition to standard clinical observations, wounds were monitored against the Saint Elian checklist system for the diabetic foot. Results: A total of 10 patients took part in the study. Complete wound closure was observed in 4/5 patients in the oral+topical group; in the remaining patient, necrotic and fibrin tissues on the wound edges were eliminated. Half (2/4) of the patients receiving oral-only Cytoreg experienced complete wound closure; one patient in this group was removed prematurely because of an unrelated illness and was not replaced. During the study, no significant differences were observed between groups in either the oxygen saturation of the affected tissues or in insulin and glycaemia levels (p<0.05). Significant increases in arterial haemoglobin and arterial oxygen partial pressure (p<0.05) were observed, and significant decreases were measured in the levels of glycosylated haemoglobin, aspartate aminotransferase, glutamic-pyruvic transaminase, creatine and urea (p<0.05). Conclusion: The results of this study justify an expanded clinical study for the treatment of DFUs with Cytoreg. [ABSTRACT FROM AUTHOR]

Beekeepers in order to control the Varroa population, apply oxalic acid (OA) by trickling, spraying, evaporating, or fumigating, onto broodless colonies for higher efficacy. Recently, a new method was developed using strips with OA and glycerin during brood-rearing periods. However, there has been little research regarding the optimum concentration of the active ingredient and the suitable solvents to reach maximum efficacy. Thus, in the present study, we applied strips with different concentrations of OA in different mixtures of glycerin, assessed the efficacy of the method throughout a 4-year experiment, and compared it with others, commonly followed by beekeepers. Among the tested concentrations of OA, the optimum was 21% (w/v) (60 g OA, 130 mL glycerin, and 100 mL water), while the presence of water made the strips more manageable. The corrected efficacy of the method ranged from 90.4% to 94.5%, despite the different climate conditions prevailing each year and the presence of brood. All the tested concentrations presented a high number of fallen mites in the first 15–18 days, as glycerin releases OA slowly into the hive. On the other hand, synthetic acaricides or other methods (fumigation, essential oils) presented a corrected efficacy range from 10.1% to 85.6%, requiring more in some formulations repetitions. No bees' toxicity was observed in all study cases. The results showed that the application of strips with 21% (w/v) OA diluted in glycerin and water seems to be more practical, leading to a successful Varroa control even in seasons with brood presence. [ABSTRACT FROM AUTHOR]

The western honey bee (Apis mellifera) is severely impacted by the parasitic Tropilaelaps mercedesae mite, which has the capacity to outcompete Varroa destructor mites (the current leading cause of colony losses) and more rapidly overwhelm colonies. While T. mercedesae is native to Asia, it has recently expanded its geographic range and has the potential to devastate beekeeping worldwide if introduced to new regions. Our research exploited the dependence of T. mercedesae on developing honey bees (brood) by combining a cultural technique (brood break) with U.S. registered chemical products (oxalic acid or formic acid) to manage T. mercedesae infestation. To evaluate this approach, we compared four treatment groups: (1) Brood Break; (2) Brood Break + Formic Acid (FormicPro®); (3) Brood Break + Oxalic Acid dribble (Api-Bioxal®); and (4) untreated Control. We found that the mite infestation rate of worker brood in Control colonies rose from 0.4 to 15.25% over 60 days, whereas all other treatment groups had infestation rates under 0.11% on Day 60. Mite fall assessments showed similar results, whereby Control colonies had 15.48 mites fall per 24 h on day 60 compared to less than 0.2 mites for any other treatment group. Evaluation of colony strength revealed that Brood Break + Formic Acid colonies had slightly reduced adult honey bee populations. No treatment eliminated all mites, so additional measures may be needed to eradicate T. mercedesae if detected in countries that do not currently have T. mercedesae. [ABSTRACT FROM AUTHOR]

The present work demonstrates a low-cost, single-step route for synthesizing ZnO, CuO, and ZnO–CuO nanomaterials using oxalic acid as a precipitating agent, avoiding using other surfactants. The current research also demonstrates the chemical reduction method for incorporating Ag nanoparticles onto the surface of the synthesized metal oxide nanostructures using sodium borohydride as the reductant. X-ray diffraction studies reveal the phase purity and crystallinity of the nanoparticles, while X-ray Photoelectron Spectroscopy characterizes the chemical states of surface elements. UV–vis spectra of the samples disclose the modifications shaped by Ag nanoparticles in the absorption characteristics and energy band gap of ZnO, CuO, and ZnO–CuO nanomaterials. The catalytic potentials of the synthesized materials are tested by monitoring degradation reactions of hazardous organic pollutants, including methylene blue and methyl orange, within a few minutes. The significant finding of the present study emphasizes the incorporation of Ag nanoparticles to ZnO–CuO nanocomposite and the use of sodium borohydride in photocatalysis effectively to enhance the rates of degradation of pollutant dyes without the use of intense radiation or unique lamps by initiating a three-stage electron transfer mechanism. [ABSTRACT FROM AUTHOR]

The document titled "Contents list" is from the journal Green Chemistry, published by The Royal Society of Chemistry. The journal focuses on cutting-edge research for a greener and more sustainable future. The document provides a list of articles and papers featured in the journal's latest issue, covering a range of topics such as solar energy, catalysis, and synthesis methods. The journal aims to connect the world with the chemical sciences and reinvest its profits back into the chemistry community. [Extracted from the article]

Açaí seeds are an abundant agroindustrial residue from the Brazilian Amazon region and comprise a rich source of linear mannan polysaccharide, which offers high potential for valorization into bioactive mannose and mannanoligosaccharides. This work optimizes mannose production from açaí seeds using dilute oxalic acid as a safer and greener alternative to sulfuric acid. Experiments were performed to analyze the effects of hydrolysis temperature, time and acid concentration, achieving a maximum mannose yield of 83% when employing 6.0% w/w oxalic acid at 177 °C for 15 min. This is the highest mannose yield ever reported for a one-step hydrolysis of recalcitrant linear mannan using an organic acid. In addition to mannose, this process coproduces mannanoligosaccharides in 9.6% yield. Furthermore, the economic viability of this novel process is demonstrated on an industrial scale via process simulation and techno-economic analysis of a biorefinery processing 6000 kg h−1 of açaí seeds. The simulated process considered oxalic acid recovery and recycling by chromatography, avoiding the use of a base for hydrolysate neutralization and the generation of salt waste, thus minimizing the environmental impacts of the process. The techno-economic analysis revealed a high profitability for a mannose selling price of US$ 10 per kg, resulting in a net present value of US$ 188 million and a payback period of 2.5 years after startup. Therefore, this work provides significant advances in mannose production, offering an efficient and economically viable one-step hydrolysis process that reduces waste, uses renewable raw materials and less harmful chemicals, and has the potential to contribute to a circular bioeconomy in the Amazon region. [ABSTRACT FROM AUTHOR]

Choline chloride (ChCl) based binary and ternary deep eutectic solvents (DES) were evaluated for methylene green electropolymerization with oxalic acid (OA) and ethylene glycol (EG) as hydrogen bond donors. Binary DES ChCl : OA in molar ratios 1 : 1 and 2 : 1 and ChCl : EG 1 : 2 and ternary DES (tDES) in different molar ratios and percentages of water were evaluated. The highest polymer growth was in ChCl : OA : EG‐tDES with 13% added water, that had a lower viscosity and higher ionic conductivity when associated with HCl as dopant. This enhanced the formation of more cation radicals and, consequently, more polymer formation. The PMG/MWCNT/GCE‐tDES sensor was successfully applied to the simultaneous determination of 5‐aminosalicylic acid (5‐ASA) and acetaminophen (APAP) by differential pulse voltammetry in the concentration range 1 μM–200 μM, with detection limits of 0.37 μM and 0.49 μM for 5‐ASA and APAP, respectively. The sensor demonstrated good repeatability, reproducibility and stability, and was successfully applied in pharmaceutical formulations. [ABSTRACT FROM AUTHOR]

In lead (Pb)-contaminated soil, inoculating phosphate-solubilizing bacteria (PSB) to reduce the phytoavailability of Pb and to change the soil nutrients is an important way to inhibit the Pb uptake by plants. In this study, we isolated the native Pb-resistant Pantoea rwandensis from a tailings site. We employed broth culture and pot experiments to investigate the effect of the inoculation of P. rwandensis on Pb immobilization in the soil, the soil nutrients, the microbial community, and Pb accumulation in the biomass of maize (Zea mays L.). The results showed that P. rwandensis not only tolerated Pb2+ but also dissolved Ca3(PO4)2 by secreting oxalic acid, tartaric acid, lactic acid, and acetic acid, which significantly increased the amount of dissolved P, up to 567.50 mg.L-1. In the pot experiment, the application of culture filtrate, an inoculation with P. rwandensis, or a mixture of culture filtrate and P. rwandensis increased the soil residual Pb by 49.57%, 89.81%, and 41.69%, respectively, compared to the control. Consequently, the increase in the residual Pb in the soil inhibited its uptake by maize, and an inoculation of P. rwandensis or a mixture of culture filtrate and P. rwandensis decreased the accumulation of Pb in the shoot biomass of maize by 61.65% and 72.48% and in the roots of maize by 26.00% and 39.59%, respectively. Meanwhile, P. rwandensis and the mixture of culture filtrate and P. rwandensis increased the shoot biomass of maize by 54.39% and 17.86% and the root biomass of maize by 108.77% and 17.86%, respectively. A P. rwandensis inoculation increased the biodiversity of the fungal community and the abundance of Proteobacteria, Mortierella, and Sphingomonas. Our results demonstrate that an inoculation with P. rwandensis could promote the transformation of Pb fractions and a functional change in the soil bacterial community, ultimately decreasing Pb accumulation in the biomass and promoting the development of maize. [ABSTRACT FROM AUTHOR]

One of the few synthetic resins from petroleum-based sources that are biodegradable and can reduce the environmental pollution is polyvinyl alcohol (PVA). PVA film is non-toxic, transparent, and biocompatible in line with green ecologically friendly requirements. It is completely biodegradable and possesses good mechanical properties, chemical resistance, and gas barrier. PVA's hydroxyl groups, however, decrease its mechanical and thermal properties and make it water-soluble, which limits its use. However, it is possible to control the water solubility or absorption by partially cross-linking the polymer chains. This work aims to enhance the mechanical properties while making an insoluble film through cross-linking with oxalic acid (OA). In the present investigation, PVA film was cross-linked with OA (with variable weight percentage (wt%) of OA) to limit its ability to absorb moisture. Tensile testing was utilized to evaluate the mechanical properties of the films, revealing their ultimate tensile strength, % elongation, and Young's modulus. With increase in wt% of OA, % elongation of PVA-based films decreases, whereas maximum tensile strength was observed at 10 wt% of OA configuration. In comparison to neat PVA, the differential thermo-gravimetric analysis peak migrated towards the higher temperature side with an increase in the OA concentration. The peak value of tan δ curve also increased and shifted towards higher temperature side as the OA concentration increased. This concludes that prepared films have high damping coefficient and can absorb impact load. Finally, the films' creep-recovery behaviour was also examined in detail. To represent the potential application of these films as packaging materials, anti-microbial tests were also conducted. [ABSTRACT FROM AUTHOR]

The graphene oxide (GO) membrane treated by ozone, GOL, exhibits a relatively high conductivity, but its mechanical strength cannot be maintained due to severe swelling. To further improve the conductivity while suppressing the swelling, the free-standing GO membrane was subjected to ozone treatment and subsequently modified by crosslinking agents with oxygen functional groups, i.e., glyoxal (GLX) and oxalic acid (OXA). The modified membranes, GLX/GOL and OXA/GOL, successfully reduced the swelling and increased the conductivity to provide an excellent power output of a fuel cell at 30 °C due to the increased oxygen functional groups and the carbon defects. Furthermore, OXA/GOL exhibited a significant stability at elevated temperatures. At 50 °C, the through-plane conductivity and power output increased to 23.5 mS cm−1 and 317 mW cm−2, respectively. This is considered to be due to the relatively high thermal stability of the carboxy group added by the OXA modification. [Display omitted] • The agents with oxygen functional groups were used to crosslink GO layers. • The modified GO membranes showed improved conductivity and reduced swelling. • OXA/GOL exhibited the highest conductivities among the modified GO membranes. • OXA/GOL demonstrated a stable performance at higher temperatures. • A power density of 317 mW cm−2 at 50 °C was achieved by OXA/GOL. [ABSTRACT FROM AUTHOR]

Self adhesion is a simple and effective bonding technique that can be used to produce environmentally friendly and green straw-based fiberboard (CLS) through deep eutectic-like solvent (DES) treatment. This article mainly introduces the use of DES composed of choline chloride and oxalic acid. DES is diluted with deionized water and straw is immersed in it, and finally dried into pretreated fiber raw materials. Fiber boards are prepared by adjusting the hot pressing parameters and the preset moisture content of straw itself for hot pressing solidification. The aim of this study was to investigate the effects of different processing parameters (hot pressing temperature and straw moisture content) on the microstructure, physical properties, and mechanical properties of CLS. Straw-based fiberboard heated at 180 ° C exhibited the best mechanical and water resistance performance. The fiberboard reached its highest mechanical performance at a moisture content of 50%. The bending performance of fiberboard produced at 180 °C reached 13.5 MPa, and compared with the board manufactured at 120 °C, the bending strength, tensile strength, and internal bonding strength increased by 320%, 224%, and 280%, respectively. [ABSTRACT FROM AUTHOR]

The exogenous application of oxalic acid is a potential approach to amplifying phytoremediation performance on Cd-contaminated soils. However, few studies explore the optimal oxalic acid application regime from a perspective of coupling different concentrations and timings to maximize Cd removal rate. Given this, a pot experiment was conducted using oil sunflower (Helianthus annuus L.) as the test plant. Oxalic acid was added to the pots at concentrations of 1, 2, 3, 4, 5, and 6 mmol/kg at 20, 30, 40, and 50 days after emergence. A control (CK) without exogenous oxalic acid was also included. We examined the discrepancies in various soil Cd forms, sunflower height, plant non-protein thiol (NPT) levels, and soil Cd remediation efficiency under different oxalic acid application regimes. The results showed that applying oxalic acid at a concentration of 4 mmol/kg reduced the proportion of Fe-Mn oxide Cd and organic Cd compared to the control (CK), while increased the proportion of available Cd. The optimal application time is 30 or 40 days after emergence. The addition of exogenous oxalic acid promoted the growth of sunflowers, with the greatest increase in plant height observed when 4 mmol/kg oxalic acid was applied at 30 days after emergence. Exogenous oxalic acid enhanced the absorption of Cd by sunflower roots, with the total Cd accumulation in roots, stems, and leaves being higher than in the control (CK). When 4 mmol/kg oxalic acid was applied at 30 days after emergence, the total Cd accumulation in roots, stems, and leaves was highest. Under different application times and concentration levels of oxalic acid, Cd accumulation was highest in roots, followed by leaves, with stems showing the lowest accumulation. The NPT content in each part is as follows: root > stem > leaf. Applying 5 mmol/kg oxalic acid after 30 days of sunflower emergence resulted in relatively higher total NPT content in roots, stems, and leaves compared to the control (CK). The TOPSIS model was used for comprehensive evaluation, which showed that 4 mmol/kg oxalic acid application at 30 days after emergence could be used as the optimal oxalic acid application regime for phytoremediation. These findings indicate that the addition of oxalic acid effectively promoted the absorption of Cd by sunflower and increased the efficiency of Cd removal from the rhizosphere soil, with the optimal removal of soil Cd achieved by applying oxalic acid at a concentration of 4 mmol/kg 30 days after the emergence of oilseed sunflower seedlings. [ABSTRACT FROM AUTHOR]

Water contamination with metals poses significant environmental challenges. The occurrence of heavy metals (HMs) prompts modifications in plant structures, emphasizing the necessity of employing focused safeguarding measures. Cadmium (Cd), lead (Pb), and chromium (Cr) emerge as particularly menacing toxins due to their high accumulation potential. Increasing the availability of organic acids is crucial for optimizing toxic metal removal via phytoremediation. This constructed wetland system (CWs) was used to determine how oxalic acid (OA) treatments of textile wastewater (WW) effluents affected morpho-physiological characteristics, antioxidant enzyme activity, oxidative stress, and HM concentrations in Phragmites australis. Multiple treatments, comprising the application of OA at a concentration of 10 mM and WW at different dilutions (25%, 50%, 75%, and 100%), were employed, with three replications of each treatment. WW stress decreased chlorophyll and carotenoid content, and concurrently enhanced HMs adsorption and antioxidant enzyme activities. Furthermore, the application of WW was found to elevate oxidative stress levels, whereas the presence of OA concurrently mitigated this oxidative stress. Similarly, WW negatively affected soil-plant analysis development (SPAD) and the total soluble proteins (SP) in both roots and shoots. Conversely, these parameters showed improvement with OA treatments. P. australis showed the potential to enhance HM accumulation under 100% WW stress. Specifically, there is an increase in root SP ranging from 9% to 39%, an increase in shoot SP from 6% to 91%, and an elevation in SPAD values from 4% to 64% compared to their respective treatments lacking OA inclusion. The OA addition resulted in decreased EL contents in the root and shoot by 10%–19% and 13%–15%, MDA by 9%–14% and 9%–20%, and H2O2 by 14%–21% and 9%–17%, in comparison to the respective treatments without OA. Interestingly, the findings further revealed that the augmentation of OA also contributed to an increased accumulation of Cr, Cd, and Pb. Specifically, at 100% WW with OA (10 mM), the concentrations of Cr, Pb, and Cd in leaves rose by 164%, 447%, and 350%, in stems by 213%, 247%, and 219%, and in roots by 155%, 238%, and 195%, respectively. The chelating agent oxalic acid effectively alleviated plant toxicity induced by toxins. Overall, our findings demonstrate the remarkable tolerance of P. australis to elevated concentrations of WW stress, positioning it as an eco-friendly candidate for industrial effluent remediation. This plant exhibits efficacy in restoring contaminants present in textile effluents, and notably, oxalic acid emerges as a promising agent for the phytoextraction of HMs. KEY MESSAGE/HIGHLIGHTS: HMs stress decreased the physiology and morphology of Phragmites australis L. OA improved the photosynthetic pigments and antioxidant enzymes HMs accumulation and bioavailability increased under OA Phragmites australis L. showed higher efficacy for textile effluent treatment under OA NOVELTY: The adoption of ecological or nature-based approaches for treating textile industry wastewater poses significant challenges. Despite laboratory and field demonstrations showcasing the potential of macrophytes for remediating metal-polluted wastewater, this study investigates the Phragmites australis to address heavy metal contamination in wastewater. This research bridges this gap by presenting the outcomes of applying oxalic acid single and in combination with wastewater to Phragmites australis, focusing on the accumulation of cadmium, chromium, and lead from textile wastewater. [ABSTRACT FROM AUTHOR]

The complex marine environment often exposes concrete to seawater and acidic conditions during its service life. To investigate the effect and mechanism of special water environments on coral sand concrete, forty-five Φ50 mm × 100 mm cylindrical coral concrete specimens were prepared and cured in freshwater, seawater and oxalic acid in this study. The specimens were cured for 7, 14, 28, 60 and 90 days, respectively. The physical and mechanical properties of the specimens under the lossless state and static failure state were tested through piezoelectric transducer (PZT) test and uniaxial compression test. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed for analyzing the mineral composition and microstructure of the specimens. The results show that the compressive strength of the specimens in seawater and freshwater initially increased and then stabilized with the curing age, whereas in oxalic acid it initially increased and then decreased. The compressive strength of the specimens at 90 days in freshwater, seawater and oxalic acid solution have increased by 54%, 18% and 21%, respectively, compared to that at 7 days. A combination analysis using microscopic and macroscopic test indicated that the completion time required for hydration in freshwater, seawater and oxalic acid solution was 28, 28 and 60 days, respectively. This study suggests that Cl− in seawater accelerates the cement hydration process, improving the early mechanical properties of specimens. During the later hydration process, the soluble CaCl2 and expansile Mg(OH)2 generated during the later hydration process which reduces the strength. In oxalic acid solution, a dense calcium oxalate coating produced through the reaction between oxalic acid and CaCO3 would reduce the degree of hydration. The formation of CO2 would increase the porosity of specimens, thereby weakening the mechanical strength of the concrete. [ABSTRACT FROM AUTHOR]

[Display omitted] • Short-chain organic acids are readily biodegradable to CO 2 and H 2 O. • Selective leaching of Mo/V and Ni from HDS catalysts with organic acids is achieved. • The leaching of metals is jointly influenced by acidolysis and complexolysis. • Roasting pre-treatment is applied to maximize extraction efficiency. • Different leaching processes of Mo and V in HDS catalysts were identified. This article employs six organic acids to selectively dissolve Mo, Ni and V from spent catalysts, and the most effective acid is identified. Then, the effects of key leaching parameters, including acid concentration, temperature, and S/L ratio, on metal leaching are systematically explored to determine the leaching mechanism. The results demonstrate that the leaching ability of organic acids followed the order: oxalic acid > citric acid > tartaric acid > malonic acid > acetic acid > formic acid. The leaching process of metals was jointly influenced by acidolysis and complexolysis. Among them, more than 93.07 % of Mo, 86.64 % of V, and 74.21 % of Ni were selectively leached with oxalic acid at the optimum condition: S/l: 1/20, oxalic acid: 1.0 mol/L, temp: 60 °C. From the correlation coefficients, the resulting activation energies, and n values, it was demonstrated that Mo and V followed the Avrami dissolution reaction model, V leaching was controlled by the diffusion mode, and Mo leaching was controlled by a mixed mode of chemical reaction and diffusion. The dissolution behavior of both metals consistently adhered to the linear trend of the Avrami kinetic model under varying S/L ratios and oxalic acid concentrations. [ABSTRACT FROM AUTHOR]

With the purpose of economizing the routine soil testing for micronutrients and avoiding the use of multiple soil extraction procedures, a laboratory investigation was attempted to evaluate a new chemical extractant for assessing the availability of common micronutrients (Fe, Cu, Mn, Zn, Mo, and B) in soils of widely varying properties (n = 32). The new extractant designated as OM-MES-VERA# contained 0.01 M oxalic acid, 0.02 M maleic acid, 0.02 M 2-(N-Morpholino) ethane sulfonic acid (MES), 0.0025 M ethylene diamine tetraacetic acid di-sodium salt, 0.02 M acetic acid, and 0.1% polyacrylamide (final pH adjusted to 6.0). OM-MES-VERA extracted significantly higher amounts of micronutrient cations and B from soils compared to the conventional diethylene triamine pentaacetic acid (DTPA, pH 7.3) extractable micronutrient cations and hot water soluble B, respectively, but lesser amount of Mo compared to Mehlich-3 universal extractant. Soil test values by both OM-MES-VERA- and conventional extractants were correlated with soil properties. The labile (E and L) values of micronutrient cations and Mo estimated by isotopic dilution method, ammonium bicarbonate-DTPA, pH 7.6 extractable soil B (as an estimate of E for B) and B concentration in maize (as an estimate of L for B) were successfully regressed on soil test values of micronutrients by OM-MES-VERA and conventional soil extractants except in the case of DTPA (pH 7.3) for E-value of Fe and L-value of Mn. The OM-MES-VERA extractant can be considered to assess the availability of common micronutrients in soils of diverse soil properties. [ABSTRACT FROM AUTHOR]

Dark chocolate presents exclusive characteristics that make it a food product with worldwide consumption and also as an ingredient in several food industries. Although chocolate is an energy-dense food, it is also rich in bioactive compounds and recent studies have demonstrated health benefits from a moderate consumption. Therefore, the quantification of the bioactive compounds of different types of cocoa, from different geographical origins, is of great importance to recognize the importance of single origin dark chocolate from the nutritional point of view. Dark chocolate produced from Amelonado variety presented higher values of hardness (5592 g), plastic viscosity (2.87 Pa.s) and yield value (12.91 Pa). Both dark chocolates from Peru, Piura Blanco and Chuncho, presented higher results in total phenolic content, total antioxidant capacity, caffeine and vitamin E. Additionally, sample Piura Blanco presented a higher content of theobromine (720.7 mg/100 g), lactic acid (1153.2 mg/100 g), succinic acid (679.4 mg/100 g) and oxalic acid (468.5 mg/100 g). On the other hand, chocolate from São Tomé presented a higher content of sucrose (38.22%) and SFA (62.38% of total fat). The results obtained demonstrate the existence of heterogeneity in cocoa varieties, supporting decision-makers in the selection of the most suitable cocoa for specific market needs. [ABSTRACT FROM AUTHOR]

Copyright of Inorganic Chemicals Industry is the property of Editorial Office of Inorganic Chemicals Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Phytoremediation is an important method for refining heavy metals, but the main limitation is the low bioavailability of the metals. Chelating agents, by releasing heavy metals from the soil solid phase, can increase their uptake by the plants. In this research, the effects of some chelating agents on the phytoremediation of Vicia faba in a calcareous soil contaminated with Cd were investigated. A factorial experiment was conducted based on a completely randomized design with three replications in the greenhouse of Razi University. The factors included Cd at four levels (0, 5, 10, and 15 mg kg-1 soil as CdCl2), and three chelating agents including ethylene di-amine tetra acetic acid (EDTA), citric acid (CA), and oxalic acid (OA), at two levels (4 and 8 mmol kg-1 ). The results showed that the highest Cd concentration in the root and shoot (39.90 and 27 mg kg-1, respectively) was obtained at 15 mg kg-1 of Cd and 8 mmol kg-1 of EDTA, CA, and OA. The highest values of transfer factor (0.67) and biological accumulation factor (5.65) were obtained at the highest level of Cd pollution and 8 mmol kg-1 of chelating agents. This indicates that firstly, cadmium was mainly accumulated in the root and was less transferred to the shoot. Secondly, it shows the potential of bean in phytoremediation and Cd uptake. Also, the amounts of the measured factors with citric and oxalic acid were not much different from EDTA, and therefore, these two environmentally friendly natural chelating agents could be used instead of EDTA. [ABSTRACT FROM AUTHOR]

Mulberries (Morus alba L.) contain rich and beneficial nutrients for human health. However, as a temperate adaptive species, high-temperature and high-humidity climate conditions may alter the main nutritional value of mulberries after their intended arrival in tropical regions, which has not yet been reported on. In this study, we analyzed the differences in morphology, sugars, organic acids, free amino acids, and aroma contents of five mulberry varieties in the tropics between two harvesting periods. The results show that the full-ripe fruits of M. laevigata W (TLM) have the longest fruit length (83.67 mm) and highest brix (25.90); meanwhile, full-ripe fruits of M. atropurpurea R (D10M) have the longest fruit transverse stem (20.00 ± 0.577 mm) and single-fruit weight (9.63 ± 0.033 g). Fructose, glucose, and sucrose were the main sugars, and oxalic acid, quinic acid, malic acid, and citric acid were the main organic acids in all varieties; in addition, the sucrose content in mature fruits of M. laevigata W. (BLM) and M. alba L. BZZ (BZM) was significantly higher than other sugars. Twenty free amino acids were detected in all five varieties and asparagine was the main free amino acid. A total of 100 volatile compounds were identified, including 31 esters, 20 aldehydes, 14 hydrocarbons, 11 alcohols, 10 acids, 6 ketones, and 8 others. Although the main components of five mulberry full-ripe fruits were significantly higher than the green-ripe fruits, gamma-amino butyric acid and a few other components were otherwise. The research results show that the tropical climate conditions could increase the main nutritional components of mulberries, but the specific molecular regulatory mechanisms need to be further analyzed. [ABSTRACT FROM AUTHOR]

Copyright of Low-Carbon Chemistry & Chemical Engineering is the property of Low-Carbon Chemistry & Chemical Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)