Acetic Acid Solution Research Articles

Dolomite dissolution and porosity enhancement simulation with acetic acid: Insights into the influence of temperature and ionic effects

Dolostone reservoirs are crucial for global oil and gas storage, holding a significant portion of hydrocarbon reserves within carbonate formations. Understanding the chemical mechanism of dolomite dissolution with organic acids and associated porosity development in these reservoirs is vital for optimizing hydrocarbon recovery. In this work, two sets of simulation experiments are designed to understand the controls of temperature and ionic effects on porosity enhancement during the dissolution of dolomite with acetic acid. In specific, we discovered a three-step reaction process between dolomite and acetic acid, involving acetic acid dissolution in water, acetic acid dissociation, and dolomite dissolution. Burial environments with higher temperatures reduce the degree of acetic acid dissociation, leading to a corresponding decrease in dolomite dissolution in acetic acid solutions. The presence of salt ions in the solution influences the reaction process, with magnesium chloride (MgCl2) having the most significant enhancing effect on dolomite dissolution, followed by sodium chloride (NaCl), while calcium chloride (CaCl2) has a limited impact. Sodium sulfate (Na2SO4) enhances dolomite dissolution at lower temperatures; however, at higher temperatures (>100 °C), it may reduce dolomite dissolution due to the precipitation of CaSO4. Despite a relatively short open-flow time, episodic burial dissolution of dolomite by acetic acid fluids under overburden pressure leads to a "net increase" in the reservoir space and enhances its connectivity attributes. During burial diagenesis, geological forces episodically drive organic acid fluids to the dolomite reservoir, predominantly dissolving dolomite along pre-existing pore development zones and geological interfaces, exhibiting inheritance, episodicity, and localization characteristics. Overall, this study provides insights into the dissolution and diagenetic processes of dolomite in the presence under acetic acids, from the point of dissolution simulation experiments. Collectively, these findings enhance our understanding of pore-system evolution and fluid-rock interactions in deep carbonate reservoirs.

Catalytic oxidation of 4-nitro-a-phenylethanol by ozone in acetic acid solution

For the first time, a systematic study of kinetic features of the reaction of 4-nitro--phenylethanol (an intermediate product of oxidation of 4-nitroethylbenzene) with ozone was conducted. The results of the work showed the ways to transform 4-nitro--phenylethanol into 4-nitroacetophenone. It was shown that unlike the reaction of ethylbenzene ozonation when the attack by benzene ring prevails, 4-nitro--phenylethanol was oxidized by ozone only by the lateral chain with the formation of 4-nitroacetophenone with the yield of 98%. The presence of manganese (II) acetate did not affect the selectivity of oxidation by the lateral chain and the yield of 4-nitroacetophenone remained 98%, however the oxidation rate increased almost three times. To find out this fact, the kinetics of the reaction of alcohol with manganese (IV) acetate in acetic acid was studied at the temperature of 283 K. It was shown that 4-nitroacetophenone is the reaction product in the atmosphere of nitrogen. At the conversion of 4-nitro--phenyletanol of 15% per mole of the converted substrate, it was consumed about one mole of Mn (IV). In the temperature range of 283–343 K, the concentration of Mn(IV) in the system at the reaction beginning was rapidly reduced, and then the reaction was inhibited. The degree of recovery of manganese, which inhibited the reaction, depended primarily on the temperature: the higher is the temperature, the higher is the degree of manganese transformation. The rate of Mn(IV) recovery was influenced by its initial concentration and the concentration of alcohol in the first stage, whereas it was inversely proportional to the concentration of Mn(II). In the process of oxidation of 4-nitro--phenylethanol by ozone at a temperature of 283 K, which is optimal, the variation of the concentrations of reagents and catalyst under studied conditions did not affect the selectivity of oxidation with respect of 4-nitroacetophenon, but was markedly reflected at the reaction rate. The reaction rate was proportional to the concentration of ozone raised to the first power and the concentrations of metal and substrate raised to the power of 0.5. The rate of oxidation of alcohol depended on the temperature: it increases twice with an increase in the temperature from 283 K to 303 K, oxidation being accompanied by a decrease in the oxidation selectivity with respect of 4-nitroacetophenon from 98% to 92%, which is associated with the acceleration of the rate of further oxidation of ketone.

Effect of Additions of Mixtures of Sodium Sulfite and Formic and Acetic Acid on the Photocatalytic Reduction of Water with Cadmium Sulfide Suspensions

The photochemical reduction of water with cadmium sulfide suspensions containing mixtures of sodium sulfite and formic and acetic acid solutions has been studied by electromotive force measurements and gasometry. The sulfite ions are oxidized on the anode in the sulfite–acetate suspensions; the sulfite ions and formic acid, in the sulfite–formate solutions. Hydrogen peroxide was found among the products of the photochemical reaction; it is involved in the oxidation of the radicals of sulfite ions and molecular sulfur of CdS particles and prevents the reduction of water.

Fish Scale Gelatin Nanofibers with Helichrysum italicum and Lavandula latifolia Essential Oils for Bioactive Wound-Healing Dressings.

Essential oils are valuable alternatives to synthetic antibiotics that have the potential to avoid the pathogen resistance side effects generated by leather. Helichrysum italicum and Lavandula latifolia essential oils combined with fish scale gelatin were electrospun using a coaxial technique to design new bioactive materials for skin wound dressings fabrication. Fish scale gelatins were extracted from carp fish scales using two variants of the same method, with and without ethylenediaminetetraacetic acid (EDTA). Both variants showed very good electrospinning properties when dissolved in acetic acid solvent. Fish scale gelatin nanofibers with Helichrysum italicum and Lavandula latifolia essential oil emulsions ensured low microbial load (under 100 CFU/g of total number of aerobic microorganisms and total number of yeasts and filamentous fungi) and the absence of Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 10536, and Candida albicans ATCC 1023 as compared to fish scale gelatin without essential oils, which recommends them for pharmaceutical or topical applications. A scratch-test performed on human dermal fibroblasts proved that the biomaterials contributing to the wound healing process included fish scale gelatin nanofibers without EDTA (0.5% and 1%), fish scale gelatin nanofibers without EDTA and Lavandula latifolia essential oil emulsion (1%), fish scale gelatin nanofibers with EDTA (0.6%), and fish scale gelatin nanofibers with EDTA with Helichrysum italicum essential oil emulsion (1% and 2%).

Characterization of polyhydroxybutyrate production from Halomonas titanicaeKHS3 and manufacturing of electrosprayed nanoparticles

AbstractPolyhydroxyalkanoates (PHAs) are biopolymers accumulated by a diversity of bacterial strains as carbon and energy reserve when grown under unbalanced nutritional conditions. Among the wide spectrum of applications for these biopolymers, the generation of nano and microparticles has drawn huge attention. PHA nanoparticles showed a high surface‐to‐volume ratio that makes them interesting for pharmaceutical uses. Bacteria from the Halomonas genus became interesting tools for biopolymer production in the last years, due to its metabolic plasticity that allows them to grow in a wide spectrum of compounds and salt concentrations. Halomonas titanicae KHS3 was previously isolated based on their ability to grow using aromatic hydrocarbons as the sole carbon source. In this work, the novelty lies in the evaluation of PHA accumulation by H. titanicae KHS3. Accumulation was successfully observed and thoroughly characterized on various carbon sources. Irrespective of the carbon source employed for growth, our experimental conditions consistently yielded PHB as the sole material identified. The truly intriguing aspect of this study is that PHB solutions in glacial acetic acid demonstrated exceptional suitability for electrospraying processing. This groundbreaking development led to the creation of nanoparticles with unique characteristics that hold immense promise for a wide range of applications.

Biopolymer-Assembled Porous Hydrogel Microfibers from Microfluidic Spinning for Wound Healing.

Hydrogels are considered as a promising medical patch for wound healing. Researches in this aspect are focused on improving their compositions and permeability to enhance the effectiveness of wound healing. Here, novel prolamins-assembled porous hydrogel microfibers with the desired merits for treating diabetes wounds are presented. Such microfibers are continuously generated by one-step microfluidic spinning technology with acetic acid solution of prolamins as the continuous phase and deionized water as the dispersed phase. By adjusting the prolamin concentration and flow rates of microfluidics, the porous structure and morphology as well as diameters of microfibers can be well tailored. Owing to their porosity, the resultant microfibers can be employed as flexible delivery systems for wound healing actives, such as bacitracin and vascular endothelial growth factor (VEGF). It is demonstrated that the resultant hydrogel microfibers are with good cell-affinity and effective drug release efficiency, and their woven patches display superior in vivo capability in treating diabetes wounds. Thus, it is believed that the proposed prolamins-assembled porous hydrogel microfibers will show important values in clinic wound treatments.

Ciprofloxacin adsorption performance of Co‐doped UiO‐66

The presence of ciprofloxacin in various water sources, even at low concentrations, causes health risks and serious environmental pollution as well as development of antibiotic resistance. So, it is critically necessary to remove ciprofloxacin effectively from the effluent. Co‐doped UiO‐66 was synthesized through one‐step hydrothermal method and evaluated as an adsorbent for ciprofloxacin adsorption. Ciprofloxacin adsorption was systematically investigated revealing adsorption isotherms, kinetics, and thermodynamics. The findings revealed that Freundlich isotherm model (maximum adsorption capacity: 45.17 mg g−1) at optimum experimental conditions (pH: 5, contact time: 90 min and adsorbent dosage: 0.3 g L−1) and acquired data were fitted using pseudo‐second‐order kinetic model. The ciprofloxacin adsorption was determined to be a spontaneous and endothermic from thermodynamic experiments. Effects of coexisting compound in the aqueous solutions on the Co‐doped UiO‐66 adsorption performance were studied using different concentrations of NaCl solution. The ciprofloxacin removal slightly decreased in the case of increasing the concentrations of Na+ ions. Regeneration of the Co‐doped UiO‐66 was carried out in methanol + acetic acid solution and repeated adsorption experiments were conducted to reveal reusability of the Co‐doped UiO‐66. Its ciprofloxacin adsorption capacity reduced to 38.0 mg g−1 after the four cycles indicating that the Co‐doped UiO‐66 was a reusable and potential adsorbent for ciprofloxacin adsorption process.

DFT, molecular docking and molecular dynamics simulations of 2-imino-4-oxo-1,3-thiazolidine hydrochloride and its activity against Bacillus pasteurii urease

Abstract According to reports, the bioactive thiourea derivative was prepared from the ethanol solutions of thiourea and chloro acetic acid in a 1:1 M ratio. DFT calculations of 2-Imino-4-oxo-1,3-thiazolidine hydrochloride (IOTH) were performed with the use of B3LYP and the 6-311+G(2d,p) basis set. Frontier molecular orbitals, mapped electrostatic potential (MEP) map, and nonlinear optical (NLO) properties of the IOTH were all assessed. The compound was tested for drug-likeness using Swiss ADME. Using B. pasteurii (PDB ID: 4UBP), calculations for molecular docking were then performed on the geometry-optimized structure. In order to determine the complex’s stability and the interactions between ligands and the receptor, the complex was subjected to molecular dynamics (MD) simulations. According to the results, the first hyperpolarizability value (β 0) was 7.459 × 10−24 esu. The large first hyper polarization rate theoretically supported its use in the design of NLO materials. The calculated HOMO–LUMO energy gap value of the IOTH was found to be 2.87 eV. The small HOMO–LUMO energy gap suggested that IOTH is a soft molecule with a high degree of chemical reactivity but poor kinetic stability. The molecular docking study showed that the best ligand pose energy for the IOTH was −101.35 kcal/mol whereas the standard drug (acetohydroxamic acid) was −64.29 kcal/mol. The results demonstrated that the ligand–receptor complex remained stable during the MD simulations due to high binding affinity to Bacillus pasteurii urease. The Lipinski Rule of Five was not violated in any way in the studied compound. This demonstrated that it is bioavailable. During clinical trials, the compound attrition rates would be lower, and the drug would have a better chance of being commercialized.

Preparation of modified zeolite/chitosan composites and study on the adsorption performance of Pb2+

AbstractAs one of the most common pollutants in wastewater, heavy metals seriously threaten human health and survival, and among the current removal methods, the adsorption method has attracted the most attention because of its simple and safe operation. Zeolite is a substance with a unique spatial structure, cheap cost, and environmental friendliness. Zeolite is a substance with a unique spatial structure, cheap cost, and environmental friendliness. Due to its size and high surface area‐to‐volume ratio, zeolite exhibits excellent adsorption and ion exchange properties and is a promising adsorbent. In this paper, the modified zeolite chitosan composite film was prepared by solution method by dissolving chitosan in acetic acid solution as the solvent, and the effects of zeolite content, modifier type, initial pH, pore‐making agent, adsorption time, adsorption temperature, initial concentration, and feeding amount were studied. The optimal conditions for Pb2+ adsorption were 40% modified zeolite content, 293 K in 100 mg/L solution, a feeding amount of 1 g/L, pH = 5.5, and a removal rate of 96.6% in 24 h. The isotherm is consistent with the Langmuir adsorption model, which is manifested as single‐molecule chemical adsorption, and the highest saturated adsorption capacity is 139.6 mg/g. After five cycles, it still has a greater than 90% initial adsorption effect.Highlights Chitosan‐modified zeolite composite membranes are inexpensive. After adsorption, the sorbent is easy to recover.

Preparation of Chitosan from Agaricus bisporus Brown Stems and Studying some Its Physicochemical and Functional Properties

The stems of the brown Agaricus bisporus mushroom, which were obtained from the Al-Wadq mushroom farm / Baghdad, The chemical composition of the mushroom stems was estimated as the proportions of the mushroom components: moisture, protein, fat, ash, carbohydrates (91, 2.8, 0.25, 0.88, 5.07)% respectively. Chitin was extracted from the stemsof A. bisporus brown mushrooms by chemical method using 2 M sodium hydroxide solution and 2% acetic acid. The percentage of chitin extracted from mushroom stems was 13.8%. Chitosan was prepared from the stems of A. bisporus brown using a 50% sodium hydroxide solution at a temperature of 100°C for 3 hours, and the percentage of chitosan in mushroom stems was 10.5%. The chitosan under study was identified using Fourier Transform Infra-Red (FTIR). The degree of deacetylation of chitosan produced from the stems of A. bisporus brown was 83%. The viscosity of mushroom stems chitosan was 40cP. When the viscosity was estimated by dissolving chitosan in 1% acetic acid solution, the molecular weight of mushroom stems chitosan was 46.922 kDa. The stems chitosan was distinguished by its high solubility in 1% acetic acid solution, reaching 90%.

Ameliorating effects of Acacia arabica and Ocimum basilicum on acetic acid-induced ulcerative colitis model through mitigation of inflammation and oxidative stress

IntroductionUlcerative colitis (UC) is a chronic recurrent inflammatory disease of the large intestine and rectum. The disease is characterized by oxidative stress and severe inflammation. Research has shown the anti-oxidative and anti-inflammatory effects induced by consuming the Acacia arabia and Ocimum basilicum. The present study aimed to evaluate the effect of treatment with O. basilicum together with A. arabica on healing, inflammation, and oxidative stress in the course of experimental colitis in rats. MethodsA total number of 50 male rats were selected and randomly assigned to five groups of 10 rats each. Colitis was induced in rats by enemas with a 4 % acetic acid solution. Four days after the colitis induction, the rats were orally treated for the next 4 days with saline or a combination of A. arabica and O. basilicum (1000 mg/kg) or sulfasalazine (100 mg/kg). ResultsAcetic acid-induced colitis increased the colon's macroscopic and histopathological damage scores; increased colon levels of MDA (Malondialdehyde), MPO (Myeloperoxidase), TNF-α (Tissue necrosis factor α), IL6 (Interleukin 6), and IL17 (Interleukin 17); and decreased SOD (Superoxide Dismutase), GPx (Glutathione Peroxidase), and IL10 (Interleukin 10) levels in the treated rats compared with the control group (P < 0.001). Overall, a combination of A. arabica and O. basilicum reduced macroscopic and histopathological damage scores (P < 0.01) of the colon, and MDA, MPO, TNF-α, IL6 (P < 0.001), and IL17 (P < 0.01) levels of the colon. Furthermore, it increased SOD, GPx, and IL10 levels compared to the colitis group (P < 0.01). ConclusionA. arabica and O. basilicum have improving effects on UC by reducing inflammation and oxidative stress.

Development of a fire-proof coating containing silica for polystyrene

The possibility of applying a silica-containing coating to the surface of XPS extruded polystyrene foam, which is characterized by a high degree of flammability, was evaluated. The effect of the content and concentration (11, 22, 44 and 85 %) of orthophosphate acid on the optical properties of silicic acid sols obtained by the exchange reaction between aqueous solutions of liquid glass and acetic acid was studied. The fact of incorporation of orthophosphate acid into the gel structure was confirmed by the results of acid-base titration with a sodium hydroxide solution of the intermicellar liquid isolated as a result of gel syneresis. Using an optical microscope, the structure of the polystyrene film coating after treatment with orthophosphate and sulfuric acid solutions was investigated. In both cases, the effect of an increase in the pore area and a general increase in the looseness of the surface was noted, which can help reduce its hydrophobicity and improve adhesion to the coating. The increase in hydrophilicity of the surfaces of polystyrene films after treatment with acids was also confirmed by the flatter, non-spherical shape of the drops of the composition on them. The structure of the obtained coatings on polystyrene films was analyzed. The similarity of the directions of the cracks in the case of treatment of the films with solutions of both acids was noted, and an assumption was made about the presence of uniform deformation stresses during gel shrinkage. A microscopic study of coatings on the surface of extruded polystyrene foam was conducted, and a positive effect of orthophosphate acid on the density of their structure was established. It was determined that the optimal solution for obtaining a uniform coating is the modification of the sol with the help of a 22 % solution of orthophosphate acid. Schemes of the interaction of the silica coating and the polystyrene base in cases of electrostatic interaction and in the case of the formation of covalent bonds between the coating and the polystyrene surface are proposed.

Pengaruh Variasi dan Konsentrasi Pelarut Terhadap Yield Antosianin Ekstrak Bunga Telang (Clitoria ternatea L.) Sebagai Pewarna Alami

One of these resources that may be used as a source of natural dyes is the telang flower (Clitoria ternatea L). Telang flower contains anthocyanin pigments that give it a blue color so that it can be used as a natural dye that can be applied to food or drinks. The purpose of this study was to determine the anthocyanin levels in the telang flower extract using various types of solvents and solvent concentrations. The solvent variations used were acetic acid, citric acid, and tartaric acid with solvent concentrations of 0.5, 1, 1.5, and 2% (w/v). The method used in this research is the maceration extraction method with a maceration time of 25, 50, 75, and 100 minutes. The results obtained The type of acid, namely acetic acid, citric acid, and acetic acid affected the anthocyanin yield, with values of 0.4729, 0.758, and 0.785 respectively at a solvent ratio of 1: 6. Variation of solvent concentration from 0.5%, 1 %, 1.5%, and 2% (v) 2% (v) acetic acid solvent can produce a maximum anthocyanin yield of 0.254 g/5 g, citric acid is 0.317 mg/5 gram, and tartaric acid is 0.343 at a concentration of 2% ( b/v).

Development of bioplastics from Tawaro's environmentally friendly sago starch (metroxylon)

Sustainable bioplastics made from Tawaro sago starch are investigated in the study. This study is motivated by the global need to lessen the environmental impact of petroleum-based polymers and discover greener alternatives. Tawaro sago starch's amylose concentration, moisture levels, and ecologically friendly qualities are examined in the study. It carefully blends sago starch, glycerol, and an acetic acid and water activator solution to create a bioplastic. The study will examine these bioplastics' chemical composition, crystalline structure, mechanical properties, and reactions to UV radiation and microbial development. Researchers and developers are interested in sago starch, a staple meal in Palopo City, South Sulawesi Province, Indonesia, as a sustainable material. Sago starch is advantageous due to its renewable nature and eco-friendly properties. XRD, mechanical characteristics, and microbiological development in sago bioplastic are examined in the study, providing valuable insights. Tawaro sago bioplastic has no heavy metals, according to XRD. The mechanical characteristics have improved significantly, reaching 2,867 N/mm². A 48-hour UV radiation exposure within limitations changed the chemical chain, causing the improvement. Furthermore, bacteria grow swiftly on sago bioplastic. This research promotes sago-based bioplastics as an eco-friendly alternative to traditional plastics, promoting environmental sustainability. This research supports the global drive to create eco-friendly materials. Using Tawaro sago starch, creative solutions for a greener, more sustainable future are possible, with bioplastics offering a compelling alternative to existing plastics and lowering their environmental impact.

Modification of QuPPe-PO-Method for the Determination of Glyphosate and Aminomethylphosphonic Acid using High Strength Silica Chromatographic Column

Glyphosate (Gly) is a popular herbicide often used for crop desiccation. The use of glyphosate leads to the contamination of the agricultural products as well as soil, surface and groundwater. For food safety control and environment monitoring, a method developed based on liquid chromatography tandem mass spectrometry, which allows quantitative determination of glyphosate and aminomethylphosphonic acid (AMPA), without derivatization. The LOQ of Gly and AMPA in raw materials of plant origin is 0.1 mg/kg; LOQ of Gly in water is 0.001 mg/L, AMPA is 0.002 mg/L; LOQ of Gly in soil is 0.02 mg/kg, AMPA is 0.04 mg/kg. Extraction from raw materials of plant origin was performed by acetic acid solution of methanol in water, in the presence of EDTA-Na2 and dichloromethane. Extraction from water was carried out in the presence of EDTA-Na2 and acetic acid. From soil, Gly and AMPA were extracted with 0.1% of ammonia solution. The extracts are purified on OASIS HLB; proteins were precipitated with acetonitrile, an aliquot of the extract was concentrated. The resulting calibration dependence equations were linear and the correlation values (R) were ≥ 0.99. Relative standard deviation values were in the range of 1.77-19.5%, while the recoveries were from 80.5 to 108%.

Differences in Urine Protein Levels of Hemodialysis Patients With Acetic Acid and Lemon Juice Examination

Background and Objectives: Urine protein examination is a routine examination performed to determine kidney function. The principle of urine protein examination is that the protein in urine is denatured by heating and adding acid. Lemon fruit has a high acid content and lemon has similar properties to acetic acid, namely properties as a weak acid with a pH of 3.0. The direction of this research is to understand the comparison of urine protein using lemon juice and acetic acid solution reagents. Methods: This research uses experimental techniques because urine is treated directly by testing using a 6% acetic acid solution (control) and lemon juice solution. Results: the examination results using lemon juice solution are the same as the examination results using 6% acetic acid solution (control), using the Wilcoxon test, the Asymp.sig (2-tailed) value is 1.000. With the provisions of the test &gt;0.05, Ho is accepted and Ha is rejected, so testing the difference in urine protein levels of hemodialysis patients with acetic acid and lemon juice examination can be carried out. Conclusion: The results of urine protein examination with acetic acid (control) and lemon juice as an alternative reagent. There is no difference in the results of urine protein examination using 6% acetic acid reagent and lemon juice.

Enhanced hydrogen generation in low-range acidic solutions using Mg2NiH4 powders and their mixtures ball-milled with NaCl and fused silica

Hydrogen production through hydrolysis shows a promise as a green and sustainable energy source that can be used for urgent need of energy on-board. This study presents a novel approach to boost the speed of hydrolysis reactions by utilizing Mg2NiH4 powder. The approach involves ball milling with NaCl and fused silica additives, that open additional active areas and accelerate the hydrolysis process. A comprehensive analysis encompasses morphology, elemental mapping, chemical bonding, structural changes, and surface area determination of the prepared powders. The hydrolysis reactions is performed using acetic acid solutions with different molarities (0.25 M, 0.12 M, and 0.06 M), as well as tap water. The impact on kinetics is profound, with reaction rates varying between 600 and 3000 ml/min during the initial seconds for different powders. Moreover, the study examines the application of such hydrolysis system for electricity generation through a proton-exchange membrane fuel cell.

Evaluation of pesticide residues in selected vegetables from Kuala Lumpur, Malaysia using modified QuEChERS and assessment of washing methods

Growing population in Malaysia has resulted in increased production of local vegetables as well as pesticide usage. This constitutes a health risk to human health. In the present work, the level of ten pesticide residues namely chlorpyrifos, profenofos, aldrin, endrin, cypermethrin, lambda-cyhalothrin, carbendazim, propamocarb, imidacloprid, and thiamethoxam in ten types of vegetables collected from six local markets were measured using modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS) and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Results showed that 13.3% samples contained pesticide residues above the maximum residue limit (MRL) prescribed by the Malaysian Food Regulations 1985, 55.0% of samples contained pesticide residues below the MRL, and no pesticide residues were detected in 31.7% of samples. Carbendazim and chlorpyrifos were among the highest pesticides detected in the samples. For the type of vegetables, kale and spinach contained high concentrations of pesticide residues above the MRL. In order to produce safe vegetables, the efficiency of different washing methods (tap water, 10% sodium bicarbonate solution, and 10% acetic acid solution) in reducing carbendazim and chlorpyrifos residues in a kale model system was evaluated. Results showed that the levels of carbendazim and chlorpyrifos reduction for all three methods were significantly different (p &lt; 0.05) with 10% acetic acid solution being the most effective followed by 10% sodium bicarbonate solution, and tap water. Washing kale with 10% acetic acid reduced 76.0 and 41.2% of carbendazim and chlorpyrifos, respectively. Therefore, it is recommended for consumers to practice 10% sodium bicarbonate washing method by soaking vegetables with an acidic solution followed by rinsing with tap water to reduce pesticide residues, and minimise the exposure to hazardous pesticides.

Technological evaluation and determination of the traits stability in breeding materials in the early generations

The experiment was carried out on an experimental field of Institute of Plant Genetic Resources “K. Malkov”, Sadovo during the period 2016 - 2018. Nineteen common winter wheat lines and variety Sadovo 1 were studied, under the controlled trial conditions. The purpose of the research is technological evaluation and determination of the stability of traits in breeding materials in the early generations. The analyzes were carried out in a laboratory to assess the technological qualities of the grain. For the characterization of the studied lines, the following traits were taken into account: sedimentation value (SV) - using a 2% solution of glacial acetic acid (Pumpyanskiy, 1971); fermentation number FN - Pelshenke test (PT) by mixing a sample with live yeast in two repetitions (Pelshenke et al., 1953). The traits stability of breeding material was evaluated by the stability variances σi2 and Si2 according to Shukla (1972), the equivalency Wi according to Wricke (1962) and the criterion of phenotypic stability (Ysi) according to Kang (1993). The program product IPCSSVKYSI (Interactive program for calculating Shukla’s stability index (Ysi), developed by Kang &amp; Magari (1995) was used to determine the stability index. The highest value for the trait sedimentation value was reported for line RU 32/2072.73.74, followed by line RU 47/3504. With a high value of the trait fermentation number are the lines RU 32/2072.73.74, RU 91/1729; RU 93/1895 and RU 128/2900. The influence of the factors genotype, environment and their interaction on the phenotypic appearance of the studied traits has been significant. The following lines can be highlighted as valuable breeding materials: RU 32/2072,73,74 and RU 47/3504 (high value and stability of the traits of sedimentation value and fermentation number). RU 49/2300 (high value and stability of the trait sedimentation value). RU 91/1729 (high value and stability of the trait fermentation number) The listed genotypes can be successfully used in breeding and improvement work to create new and high-quality common winter wheat varieties.

A Comparison Study of Roseolumiflavin Solvates: Structural and Energetic Perspective on Their Stability

Roseolumiflavin is a deep red microcrystalline derivative of isoalloxazine that exhibits a weak photophysical activity in the solid state. In aqueous as well as in acidic solution of formic or acetic acid, respectively, it tends to form solvates. Herein, we present a set of binary and ternary roseolumiflavin solvates including one hydrate and a solvate hydrate. The impact of the solvent on solvate formation along with an in-depth structural analysis was investigated. Calculations of the lattice energies provide insight into the phase stability of the evaluated systems showing an energetic benefit for all solvates with values up to −395.82 kJ/mol. The total interaction energies between molecules calculated via Crystal Explorer further identified cofacial π···π stacks to be the most strongly bonding fragments in the crystal lattices for all systems except the formic acid solvate, followed by remarkably weaker hydrogen-bonded arrangements. The energetic contributions of single intermolecular interactions within the fragments are evaluated by an atoms-in-molecules approach. It is shown that physicochemical properties, such as thermal stability, can be tuned depending on the incorporated solvent molecules despite a high decomposition temperature of the chromophore.