Different Concentrations Of Acetic Acid Research Articles

Recovery of Copper and Zinc from Livestock Bio-Sludge with An Environmentally Friendly Organic Acid Extraction.

Pig farmers in Taiwan tend to overdose copper (Cu) and zinc (Zn) in animal feeds to ensure pig health. The application of Cu- or Zn-rich livestock compost to fields can result in high Cu/Zn residues in surface soil and violate limitations for zinc and copper in land applications. This study aims to extract Cu and Zn from sludge using organic acid or H2O2/organic acids. The livestock bio-sludge was dried and treated with different concentrations of acetic acid (1N, 2N, and 4N). The acid-extracted sludge was then treated with or without adding H2O2 during different periods (4, 24, and 48 h) to investigate the efficiency of acid extraction of Cu and Zn. The supernatant of the acid-extracted product was separated from the residues through centrifugation. Experimental results showed that the treatment set of dried bio-sludge with 2% H2O2 significantly promoted the removal efficiency of Cu and Zn from the bio-sludge (p < 0.01). The best removal efficiency of Cu and Zn from the bio-sludge was 40% and 70%, respectively, using 4N acetic acid in the 48 h group. The study shows a green method for extracting Cu and Zn from livestock sludge, enhancing the sustainability of intensive livestock farming.

A thermoresponsive hydrogel with a wide‐range tunable phase transition temperature triggered by small molecules

AbstractThermoresponsive polymer hydrogels have great potential in the fields of smart window and information encryption due to the drastic changes in transmittance caused by the phase transition at specific temperatures. The synthesis of thermoresponsive hydrogels with a wide range and sensitive temperature response is current research goal. Here, we demonstrate a polymethacrylamide (PMAAm) hydrogel with the upper critical solution temperature (UCST) ranging from 62 to −1°C by simply polymerizing the monomer in different concentrations of acetic acid (Ac) solutions. The hydrogel exhibits sensitive temperature response with a temperature hysteresis within 2°C and can maintain stable transmittance changes after 200 cycles of testing. The phase transition mechanism is revealed by combining ultraviolet visible spectra, differential scanning calorimetry, Fourier transform infrared spectra, dynamic light scattering and scanning electron microscope measurements. This thermoresponsive hydrogel can be applied in smart window and information encryption. The smart window prepared with the hydrogel had a very high ΔTlum (The luminous transmittance modulation, 94.4%), ensuring daytime illumination and privacy protection at night. Meanwhile, the smart window exhibits an excellent thermal insulation capability for energy‐saving buildings. The hydrogels with different UCST are flexibly combined to display designed patterns at different temperatures, demonstrating the ability of the hydrogels to be used for information encryption.

Acetic Acid Enables Precise Tailoring of the Mechanical Behavior of Protein-Based Hydrogels.

Engineering viscoelastic and biocompatible materials with tailored mechanical and microstructure properties capable of mimicking the biological stiffness (<17 kPa) or serving as bioimplants will bring protein-based hydrogels to the forefront in the biomaterials field. Here, we introduce a method that uses different concentrations of acetic acid (AA) to control the covalent tyrosine–tyrosine cross-linking interactions at the nanoscale level during protein-based hydrogel synthesis and manipulates their mechanical and microstructure properties without affecting protein concentration and (un)folding nanomechanics. We demonstrated this approach by adding AA as a precursor to the preparation buffer of a photoactivated protein-based hydrogel mixture. This strategy allowed us to synthesize hydrogels made from bovine serum albumin (BSA) and eight repeats protein L structure, with a fine-tailored wide range of stiffness (2–35 kPa). Together with protein engineering technologies, this method will open new routes in developing and investigating tunable protein-based hydrogels and extend their application toward new horizons.

Experimental and molecular dynamics simulation of organic structure of bituminous coal in response to acetic acid

To investigate the effect of acetic acid on the organic structure of coal, experimental studies and molecular dynamics simulations were used to jointly characterize the response mechanism of the organic structure of coal to acetic acid. The functional groups of coal after the dissolution of different concentrations of acetic acid were tested using Fourier infrared spectroscopy, and the results showed that: the sensitivity of functional groups in coal to different concentrations of acetic acid differs, and acetic acid mainly acts to break the linkage bonds between molecules and hydroxyl groups, producing a large amount of –OH; high concentrations (100% and 75%) of acetic acid react with CH2 alkanes to produce new CH2 alkanes, but low concentrations (50% and 25%) acetic acid does not undergo this reaction. In this paper, we model the solid–liquid system of coal-acetic acid reaction, simulate and characterize the reaction of bituminous coal organic structure to acetic acid, and find that: water molecules can help acetic acid molecules adsorb on the surface of coal molecules, but water molecules will occupy a large amount of space, thus affecting the adsorption of coal molecules. Most of the coal molecules have water molecules and acetic acid molecules adsorbed on the benzene ring and oxygen-containing functional group structures, while the functional groups associated with aliphatic groups in coal molecules are difficult to adsorb due to their hydrophobicity.

Impact of extraction condition on the yield and molecular characteristics of collagen from Asian bullfrog (Rana tigerina) skin

The present study is the first report on collagen extraction as acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC), which could maximize the exploitation of Asian bullfrog (Rana tigerina) skin as an alternative collagen material in food and pharmaceutical fields. Extraction methods for ASC and PSC from Asian bullfrog skin were developed using different concentrations of acetic acid (0.50, 0.75, and 1.00 M) and pepsin (1.00, 2.00, and 3.00% [w/w]). PSCs exhibited a higher extraction yield (22.59%–28.30%) and recovery (22.48%–31.12%) than ASCs. An electrophoretic study revealed that collagens possessed type I collagen. ASC with 0.75 M acetic acid (ASC-0.75) and PSC with 3.00% (w/w) pepsin (PSC-3.00) were selected and analysed on their solubility, molecular characteristics, and amino acid composition. A better solubility with a higher isoelectric point was observed for PSC-3.00 than ASC-0.75. Fourier transform infrared- and circular dichroism-spectra revealed a high-interacted compact structure with a triple helical-structure of the collagen peptides, respectively. A similar amino acid profile with a high imino acid content was observed. Therefore, collagens from Asian bullfrog skin were successfully extracted, where the optimized conditions provided a high yield with less adverse effects on collagen properties and molecular characteristics.

Investigation of HPLF-111624 in Modified Experimental Models of Ulcerative Proctitis and Anal Fissure in Rats.

BackgroundAlthough ulcerative proctitis (UP) and anal fissure (AF) are common anorectal diseases, there are no appropriate experimental models to screen the drugs intended for these conditions. In this context, existing experimental models mimicking these diseases were modified and the polyherbal formulation, HPLF-111624 was evaluated in these models.ObjectiveTo establish animal model for UP and AF and to evaluate polyherbal formulation, HPLF-111624 in these disease models.MethodsAn experimental model of UP was selected based on the modification of the ulcerative colitis model using different concentrations of acetic acid. The concentration used for induction were 2.5%, 5% and 10% v/v and different weights used to induce AF were 25 g, 50 g and 100 g, which were selected based on the severity of inflammation, fecal score, gross pathology, and histopathological evaluation. Furthermore, these animal models were used to evaluate the efficacy of HPLF-111624, a polyherbal formulation known to be beneficial in anal diseases.ResultsAcetic acid at 5% produced typical pathological changes that resembled UP, with a significant increase in the fecal score, gross lesion, and histopathological changes. Similarly, among the three weights, physical injury with a 100 g weight produced significant changes in the histopathological score in the model of AF. Intervention with HPLF-111624 at doses of 250 and 500 mg/kg b.wt., showed a reduction in the inflammatory cytokines and a significant improvement in the histopathological findings in both the conditions.ConclusionThe results showed that the modified experimental models for UP and AF resemble the human pathological conditions and are simple, versatile and may be used for screening drugs intended for these conditions. Intervention with HPLF-111624 was found to be effective in improving the pathological state of UP and AF.

Optimization of the acetic acid method for microfossil extraction from lithified carbonate rocks: Examples from the Jurassic and Miocene limestones of Saudi Arabia

An optimization experiment with different acid concentrations was carried out to assess the use of acid to minimum sustainable limits for the extraction of microfossils from indurated limestones. Two different limestone formations of Jurassic and Miocene ages were tested. Different concentrations of acid ranging from 50 to 100% and processing times varying from 2 to 10 h were tested for optimal recoveries. The acid residue recoveries show a similar trend for both formations. The weight percentage of residue with particle size >1 mm decreased as the acid concentration increased, especially in the 50–80% acid concentration range. On the other hand, the weight percentage of the smallest size particles > 0.063 mm increased as acid concentration increased. This means that the higher concentrations of acid dissolve more of the unnecessary large particles while the foraminifera, which comprise the sand fraction size, are left in the residue. Although higher acid concentrations with longer reaction times yielded better recoveries than with less reaction time, we recommended a 60% concentration of acetic acid and a reaction time of 10 h for optimal recovery of micropaleontological samples in Saudi Arabian carbonate rocks. By lowering the recommended concentration, the consumption of acid is reduced without compromising the recovery of microfossils.•Acetic acid leaching method is applied on two different age limestone samples to extract foraminifera.•Different concentrations of acetic acid are tried and tested, and consensus is made on an optimum concentration of 60% for a submersion time of 10 h.•The sample recoveries are optimal while using this concentration for a time of 10 h.

CHARACTERISTICS OF FRESHWATER MUSSEL SHELL (Pilsbryoconcha sp.) COLLAGEN ORIGINATING FROM SUNGAI PAKU WATERS EXTRACTED WITH DIFFERENT ACETIC ACID CONCENTRATIONS

This study was aimed to determine the characteristics of freshwater mussel shell collagen originating from Paku river waters extracted with different concentrations of acetic acid and to determine the best concentrations of acetic acid to produce the highest collagen yields. The different concentration of acetic acids to produce collagen was 0.50 M, 0.75 M and 1 M. The parameters of the analysis observed were collagen yield, proximate analysis (moisture, ash, fat, and protein content), pH and heavy metal analysis (Pb and Cd). The use of 0.50 M acetic acid concentration was the best concentration to produce collagen with the characteristics of a yield value of 18.76%, a moisture content value of 6.64%, ash content value of 82.60%, fat content value of 0.28%, protein content value of 6.81%, a pH value of 6.77, The heavy metal content of Pb 0.53 mg/kg and Cd 0.07 mg/kg.

Corrosion and Hydrogen Permeation in H2S Environments with O2 Contamination, Part 3: The Impact of Acetate-Buffered Test Solution Chemistry

This paper highlights the importance of considering the magnitude of acetate (ethanoate) species concentration on corrosion and hydrogen permeation rates, important factors associated with cracking initiation in steels for sour service qualification. Materials selection relies on standards, such as NACE TM0177 and NACE TM0284, which stipulate that oxygen pollution should be avoided during testing in H2S-containing media. The 5% NaCl test solutions in current standards are buffered using acetic acid (CH3COOH)/sodium acetate (CH3COONa) to fix the solution pH over long periods. In this third paper, as part of a series of articles that evaluate how oxygen entry modifies the corrosion of (and hydrogen permeation across) low alloy steel membranes in H2S-containing solutions, the effect that changing the solution chemistry has through testing X65 steel in different concentrations of acetic acid and sodium acetate in H2S-saturated 5% NaCl solutions, i.e., Solutions A and B (NACE TM0177-2016) and the high-strength line pipe (HLP) solution of NACE TM 0284-2016, is investigated. Increasing the total acetic acid + acetate concentration encourages a higher average X65 corrosion rate and longer-sustained hydrogen charging flux, assigned to the cathodic reaction rate enhancement by acetic acid and the iron solubilizing effects of acetates. Introducing 300 ppb of dissolved oxygen does not push the solution pH outside of the permitted error range but increases average X65 corrosion rates and, again, helps sustain hydrogen permeation flux for longer. Through an evaluation of the surface structure and electrochemical data, this appears to be due to an increase in the permeability and protectiveness of the troilite FeStroilite dominant scale and a possible acetic acid buffering of local pH increase at surface cathodic sites during corrosion. The HLP solution (at pH 3.5), with the highest acetic acid and acetate concentration, is the most aggressive. In this electrolyte, an iron sulfide overlayer structure is attained with an oxygen-rich inner layer between the metal substrate and a thick iron sulfide film.

The Impact of the Acidic Environment on the Mechanical Properties of Epoxy Compounds in Different Conditions.

The aim of this work was to determine the impact of the acidic environment on the mechanical properties of two epoxy compounds in different conditions. The samples were made from the epoxy compounds composed of the epoxy resin (based on Bisphenol A), triethylenetetramine curing agent (unmodified compound), and calcium carbonate (CaCO3) (modified compound). The epoxy compound samples were seasoned for the following period of time (i.e., one week, one month, and three months). The environment was tap water and the acidic environment had three different concentrations of acetic acid (3%, 6%, and 9%). Strength tests of the epoxy compound samples were carried out in accordance with the ISO 604 standard. In the case of the modified composition, it is noted that the samples immersed in tap water were characterized by a higher strength than in acidic environments. A similar tendency was observed for unmodified compositions, although the differences were smaller than for the modified compositions. It was also noticed that the increase in the pH of the acidic solution in many analyzed cases contributed to the decrease in mechanical properties, although the immersion time in the acidic solution is important.

Effect of acetic acid concentration on functional group and microcrystalline structure of bituminous coal

The chemical dissolution of mineral components has a good effect on increasing the permeability of coal and oil reservoirs. At present, the accomplishments have focused on the analysis of the impact of strong corrosive acids on low porosity coal rocks. However, strong corrosive acids have safety problems, and their consumption rate is fast. The weak corrosive organic acid has little research on coalbed transformation, and the influence of weak acid on coal composition needs further study. In this study, Fourier transform infrared spectroscopy and X-ray diffraction are used to analyze coal samples that are treated with different concentrations of acetic acid. The results show that the functional groups in coal are sensitive to different concentrations of acetic acid, and acetic acid mainly acts to destroy the connection between molecules and hydroxyl groups, generating a large amount of OH. After soaking in 75% acetic acid, the reduction in coal is the highest, followed by 25%, followed by distilled water, and 50% acetic acid is the weakest. Acetic acid has a destructive effect on the crystals in coal. After the crystals are destroyed, the crystals are recrystallized to form crystals with a larger particle size, which loosens the whole and increases the porosity of the coal. Analysis and fitting of experimental data show that the concentration of acetic acid at 15% to 16% has the greatest effect on the organic structure of coal, and the concentration of acetic acid has the greatest effect on the crystal structure of coal within 89–92%.

Corrosion study on low molecular organic acids in the initial condensation zone of steam turbines

Purpose The purpose of this study was to investigate the corrosion of low molecular organic acids from water-steam cycles such as acetic acid and formic acid in mental parts of steam turbine initial condensation zone. Design/methodology/approach The corrosion behavior of gray cast iron in initial condensate containing different concentrations of acetic acid and formic acid was studied by weight loss test, scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction. Findings The results indicated that gray cast iron had a certain degree of corrosion in the simulated initial condensate containing acetic acid and formic acid, but the acid corrosion of gray cast iron was not only caused by low molecular organic acid but also affected by inorganic anions such as Cl−. When Cl− existed, after removing corrosion products, surface analysis results proved that the surface of gray cast iron was rough and uneven with many cracks, which was corrected more serious. Originality/value The corrosion behavior of thermal equipment by low molecular organic acids and inorganic anions in water-steam cycles was studied. The research results can provide theoretical guidelines for corrosion control of steam turbine in power plants.

Continuous in-situ extraction of acetic acid produced by Acetobacterium woodii during fermentation of hydrogen and carbon dioxide using Amberlite FPA53 ion exchange resins

Ion-exchange resins have emerged as a promising technology for separation of targeted products from biochemical production. In this study, in-situ acetic acid extraction using Amberlite FPA53 resins was examined. The study includes initial testing of the resins for separation of different concentrations of acetic acid in water along with continuous in-situ extraction of acetic acid from gas-liquid fermentation with Acetobacterium woodi on a mixture of 70% H2–30% CO2. An average acetic acid adsorption of 67.6 mg/g resin was achieved using Amberlite FPA53, significantly lower than the concentration obtained with pure acetic acid solutions (159.6 mg/g resin). This result indicates that pH and competing components in the fermentation broth influence the efficiency of the resin. Implementing in-situ extraction of acetic acid increased its production by 1.6-fold resulting in 10.21 g/L acetic acid for extractive fermentation compared to 6.4 g/L for the control, without continuous extraction of acetic acid.

Supercritical Water Gasification of Guaiacol with Acetic Acid as a Radical Scavenger: Interaction Effect on Char Formation and Gas Composition.

Supercritical water gasification (SCWG) of mixtures of guaiacol and acetic acid was carried out in a continuous reactor at 600 °C and 25 MPa with a residence time of 94 s. Different concentrations of acetic acid were employed to investigate the effect of acetic acid on product yield and gas composition. The interaction between guaiacol and acetic acid during SCWG was discussed. Acetic acid, as a radical scavenger, was found to inhibit radical polymerization, resulting in the suppression of char formation.

Agricultural-Grade Apple Cider Vinegar Is Remarkably Attractive to Drosophila suzukii (Diptera: Drosophiliadae) in Mexico.

Due to its availability and low cost, apple cider vinegar (ACV) is a frequently used as an attractant for monitoring the invasive spotted wing drosophila, Drosophila suzukii. In laboratory cage experiments, the attraction of ACV alone was compared with ACV in mixtures with different concentrations of acetic acid, propionic acid, different hydrolyzed proteins, synthetic fruit flavors (strawberry, blackberry and apple) and the addition of fruit nectars (grape, pineapple and apple). The addition of 5% apple nectar to ACV significantly increased fly captures, whereas other combinations were similar to or less attractive than ACV alone. Apple flavored vinegar was not attractive to flies. Captures did not vary significantly among the brands of ACV commonly sold in Mexico, except for one poorly-performing brand, but cup traps baited with an agricultural-grade ACV unfit for human consumption captured approximately two-fold more flies than the commercial attractants Suzukii Trap, Suzukii Trap Max Captures or ACV alone in cage experiments. Field trials performed in polytunnels planted with raspberry crops in Mexico resulted in two-fold to ten-fold higher numbers of D. suzukii captured by the agricultural-grade ACV compared to Droskidrink (a mixture of ACV, red wine and sugar), Suzukii Trap, Suzukii Trap Max Captures or edible grade ACV alone. The species selectivity of the agricultural grade ACV was similar to that of other attractants tested. Agricultural-grade ACV also captured higher numbers of female than male flies in field trials. We conclude that the remarkably high attractiveness and low cost of agricultural-grade ACV makes it a useful tool for monitoring D. suzukii populations in berry crops.

Effect of different acetic acid concentration on physicochemical characteristics of gelatin from starry trigger fish skin (Abalistes stellaris)

Starry trigger fish skin (Abalistes stellaris) is generally considered as waste from fish processing industry, especially in the traditional smoked fish industry. The purpose of this study was to determine the effect of different acid concentrations, used in the immersion process, on the physicochemical characteristics of starry trigger fish skin gelatin. Various concentration of acetic acid (0.2 M; 0.4 M; and 0.6 M) was applied during the gelatin soaking process. The experiment was done in triplicate. The extraction process was carried out for 4 hours at temperature of 55°C. The results showed that different concentration of acetic acid used in the soaking process had a significant effect (p<0.05) on the water, protein, and ash contents, yield, viscosity, gel strength, gelling point, and melting point. The results showed that the higher concentration of acetic acid used during the soaking process would affect the physical and chemical characteristics of gelatin from starry trigger fish skin (Abalistes stellaris).

Crystallinity of nanocellulose isolated from the flower waste of pine tree (Pinus merkusii)

Pine flower is an agricultural waste that has high cellulose content. Cellulose is a major material for making nanocellulose. Nanocellulose has been isolated from the flower waste of the pine tree (Pinus merkusii). The process was initiated by delignification and bleaching process with sodium hydroxide 6% and sodium hypochlorite 6% followed by hydrolysis with acetic acid under stirring at 45°C for 1 hour. Three different concentrations of acetic acid (10%, 30%, and 60%) were studied toward nanocellulose crystallinity. Nanocellulose was characterized by FTIR, XRD spectroscopy, and TEM analysis. The result shows that the % yield of nanocellulose was 87.4%, 94.2%, and 91.8% respectively. Nanocellulose has high crystallinity as indicated by the crystallinity index. Besides, the nanocellulose width is 12.82 – 21.36 nm and the length is 267.12 – 326.87 nm.

Nociceptive-like behavior and analgesia in silver catfish (Rhamdia quelen)

Fish are useful animal models in research and have been employed in developing new pharmacological approaches. This study aimed to establish the use of silver catfish (Rhamdia quelen) as an animal model to evaluate antinociceptive activity. Initially, different concentrations of acetic acid (2.5–20%), formalin 1% (1–10 μL), menthol 0.5% (1–10 μL) or vehicle were injected in the lips to establish which concentration of each sample promotes nociceptive-like behavior in various parameters. The effect of morphine (0.5–10 mg/kg) on locomotion parameters was also evaluated for antinociceptive concentration determination. Morphine was administered intramuscularly immediately prior to algogen administration. The inhibition was evaluated with the antagonist naloxone (5 mg/kg), which was administered in the same way. Recording time varied according to the algogen used in each test and locomotor activity was evaluated by ANY-maze® software. Acid acetic at 15%, 10 μL of 1% formalin, and 1 μL of 0.5% menthol were chosen since they promoted nociceptive-like behavior in several parameters. Morphine (5 mg/kg) reversed the algogen-induced nociceptive-like behavior and naloxone inhibited this effect. Therefore, the proposed experimental model demonstrated specificity for nociception, since the reversion of the nociceptive-like behavior for a compound with well-described analgesic activity was observed. This new pharmacological model contributes to evaluating compounds with analgesic potential and developing new analgesic drugs, in addition to being a promising alternative to use with rodents.

Application of fractal theory to characterize desiccation cracks in contaminated clayey soils

The formation and development of desiccation cracks in contaminated clayey soils is a complex process that affects the strength, stability, and permeability of these soils. To investigate the relationship between different concentrations of pollutants and the characteristics of the desiccation cracks in contaminated clayey soils, soil samples are prepared with different concentrations of acetic acid as the pollutant in this study. Free desiccation tests are carried out to examine the cracks in the contaminated clayey soil samples in the laboratory setting. The rate of water loss and the development of surface desiccation cracks in the soil samples with different concentrations of acetic acid are monitored. The characteristics of the structure of the surface cracks are then described and quantitatively analyzed by using a geographic information system, which involves calculating the fractal dimension with ArcGIS. The results indicate that the characteristics of the development of the surface cracks are different due to the influence of different concentrations of acetic acid. The most rapid development of cracks takes place in the soil sample with 0.4 mol/L of acetic acid, as the influence of the concentration of acetic acid on the rate of water loss is minimal. Three stages are found in the development of cracks in the soil samples: the early, intermediate, and final stages of cracking. The fractal dimension increases rapidly with increased concentration of acetic acid in the early and intermediate stages of cracking. The results therefore have significance for dealing with acid-contaminated foundation and soils.

Changes in Total Plate Counts and Quality of Pig Small Intestine by Different Washing and Packaging Methods.

Pig small intestine not only is used as food but also for sausage casings production in many countries worldwide. However, it is well recognized that the small intestine is important source of spoilage and pathogenic bacteria. The present study aimed at investigating the effects of different washing and packaging methods on the changes of microbial levels and physicochemical characteristics of pig small intestine. After collecting and trimming off of visible fats, the pig small intestine samples were treated with; (i) different packaging methods: aerobic packaging (AP), skin packaging (SP), and vacuum packaging (VP); and (ii) washing with different concentrations of acetic acid. The treated samples were then stored at 4℃ for 1, 4, 7, and 10 d. At 1-d storage, higher pH value was found in the AP-treated samples, however, after 7 to 10 days the samples treated with SP had higher values compared to the ones treated with AP and VP (p<0.05). Thiobarbituric acid reactive substances values were higher in the AP-treated samples than those of the SP- and VP- treated samples at 7-d storage (p<0.05). At 10th d, total plate counts (TPC) were higher in the control than in the acetic acid-washed samples (p<0.05). Additionally, the TPC was lower in the SP- and VP-treated samples than the AP-treated samples at 7-d storage (p<0.05). These obtained results suggest that the applications of washing with acetic acid solution and/or SP and VP methods could be an effective way to extend the shelf-life of pig small intestine during cold distribution.