Addition Of Peroxide Research Articles

On the Mechanism of Promoting the Autoignition of Rich Methanol–Air Mixtures by Small Additions of Hydrogen Peroxide

On the Mechanism of Promoting the Autoignition of Rich Methanol–Air Mixtures by Small Additions of Hydrogen Peroxide

Hydrogen Peroxide, Povidone-Iodine and Chlorhexidine Fail to Eradicate Staphylococcus aureus Biofilm from Infected Implant Materials.

Hydrogen peroxide, povidone-iodine, and chlorhexidine are antiseptics that are commonly added to irrigants to either prevent or treat infection. There are little clinical data available that demonstrate efficacy of adding antiseptics to irrigants in the treatment of periprosthetic joint infection after biofilm establishment. The objective of the study was to assess the bactericidal activity of the antiseptics on S. aureus planktonic and biofilm. For planktonic irrigation, S. aureus was exposed to different concentrations of antiseptics. S. aureus biofilm was developed by submerging a Kirschner wire into normalized bacteria and allowing it to grow for forty-eight hours. The Kirschner wire was then treated with irrigation solutions and plated for CFU analysis. Hydrogen peroxide, povidone-iodine, and chlorhexidine were bactericidal against planktonic bacteria with over a 3 log reduction (p < 0.0001). Unlike cefazolin, the antiseptics were not bactericidal (less than 3 log reduction) against biofilm bacteria but did have a statistical reduction in biofilm as compared to the initial time point (p < 0.0001). As compared to cefazolin treatment alone, the addition of hydrogen peroxide or povidone-iodine to cefazolin treatment only additionally reduced the biofilm burden by less than 1 log. The antiseptics demonstrated bactericidal properties with planktonic S. aureus; however, when used to irrigate S. aureus biofilms, these antiseptics were unable to decrease biofilm mass below a 3 log reduction, suggesting that S. aureus biofilm has a tolerance to antiseptics. This information should be considered when considering antibiotic tolerance in established S. aureus biofilm treatment.

Effects of Deacetylase Inhibition on the Activation of the Antioxidant Response and Aerobic Metabolism in Cellular Models of Fanconi Anemia.

Fanconi anemia (FA) is a rare genetic disease characterized by a dysfunctional DNA repair and an oxidative stress accumulation due to defective mitochondrial energy metabolism, not counteracted by endogenous antioxidant defenses, which appear down-expressed compared to the control. Since the antioxidant response lack could depend on the hypoacetylation of genes coding for detoxifying enzymes, we treated lymphoblasts and fibroblasts mutated for the FANC-A gene with some histone deacetylase inhibitors (HDACi), namely, valproic acid (VPA), beta-hydroxybutyrate (OHB), and EX527 (a Sirt1 inhibitor), under basal conditions and after hydrogen peroxide addition. The results show that VPA increased catalase and glutathione reductase expression and activity, corrected the metabolic defect, lowered lipid peroxidation, restored the mitochondrial fusion and fission balance, and improved mitomycin survival. In contrast, OHB, despite a slight increase in antioxidant enzyme expressions, exacerbated the metabolic defect, increasing oxidative stress production, probably because it also acts as an oxidative phosphorylation metabolite, while EX527 showed no effect. In conclusion, the data suggest that VPA could be a promising drug to modulate the gene expression in FA cells, confirming that the antioxidant response modulation plays a pivotal in FA pathogenesis as it acts on both oxidative stress levels and the mitochondrial metabolism and dynamics quality.

Optimization of a continuous flow electrocoagulation as pretreatment for membrane distillation of the waste stream in vinyl ester resin production

Vinyl ester resin production wastewater (VERW) contains high concentrations of organics particularly, methacrylic acid and bisphenol A, which are hazardous chemicals and harmful to the aquatic environment. Therefore, there is an urgent need to properly treat the effluent before discharge into the aquatic system. In this work, direct contact membrane distillation (DCMD) was explored as an advanced treatment of the VERW pre-treated by a continuous flow electrocoagulation (EC) and peroxi-electrocoagulation (PEC) processes. Optimization of EC and PEC processes were investigated and the DCMD performance was evaluated. Results showed that the optimal value of current density and polyacrylamide (PAM) dosage was 15 mA/cm2 and 1 mg/L, respectively in the EC process. For the PEC process, the optimal addition of hydrogen peroxide (H2O2) dosage was four times of the chemical oxygen demand (COD) concentration of EC effluent. The COD of VERW was effectively removed via EC followed by PEC (EC-PEC), resulting in the significant alleviation of membrane fouling during DCMD filtration of VERW. The initial flux of DCMD filtration of VERW pre-treated via EC-PEC improved by 35%, compared that only pre-treated by EC. Moreover, the concentration factor (CF) of the DCMD system reached up to 8.1 and the conductivity of distillate was less than 33.2 μS/cm. Hence, the EC and membrane distillation hybrid process paves a new way for the effective treatment of waste steam from resin production.

APLIKASI HIDROGEN PEROKSIDA DI SEDIMEN TERHADAP KUALITAS AIR DAN PERTUMBUHAN UDANG VANAME Litopenaeus vannamei

Pond bottom sediment conditions influence shrimp culture. As benthic organisms, shrimp are mainly on the surface of the pond bottom, so cultivation preparations related to improving sediment quality are essential. Pond bottom practice, such as drying, liming, and fertilizing, is common. However, in bottom pond conditions where total drying cannot be carried out, other treatments are needed, such as the addition of hydrogen peroxide. The purpose of this study was to determine the effect of adding hydrogen peroxide in pond sediments on the performance of shrimp growth and water quality. The study was conducted with five doses of hydrogen peroxide (0.25 mL, 0.5 mL, 1 mL, 2 mL) mixed with 350 g of pond soil sediment. Ten shrimps with an average weight of 0,27±0,03 g were put into the rearing container, which had been given pond bottom sediment according to the treatment. The results showed that the 2 mL hydrogen peroxide treatment gave the best results on the growth rate and average weight of Pacific whiteleg shrimp at the end of rearing. Water quality such as pH value, dissolved oxygen, and temperature were not significantly different between treatments. Hydrogen peroxide treatment can improve shrimp growth performance without affecting water quality during rearing.

Degradation of Vibrio cholerae from drinking water by the underwater capillary discharge

Abstract Underwater plasma discharge is considered a nontoxic and effectual purification approach to control waterborne bacterial pathogens. In the present study, Vibrio cholerae contaminated drinking water was sterilized by using underwater capillary discharge generation via high voltage, oxygen ( O 2 {{\rm{O}}}_{2} ) injection, and hydrogen peroxide ( H 2 O 2 {{\rm{H}}}_{2}{{\rm{O}}}_{2} ) addition. The effects of oxidant species generated by plasma discharge on V. cholerae disinfection have been studied and reported. The electrical and optical analysis of capillary discharge revealed the generation of reactive oxygen species ( OH . {{\rm{OH}}}^{.} , H and O), which are highly useful for bacterial disinfection along with enhanced power and energy of discharge pulses. Complete elimination of V. cholerae (0 CFUs (colony forming units)) from the water after O 2 {{\rm{O}}}_{2} injected and H 2 O 2 {{\rm{H}}}_{2}{{\rm{O}}}_{2} added plasma discharge was achieved, and 100% inactivation of V. cholera from drinking water was proven. The retardant effect of the initial V. cholerae colonies with time variation was reported through optical density (OD600 nm) measurements. The time course study of bactericidal activity of plasma treatment on V. cholerae, observed every 12 h up to 36 h, revealed a high retardant effect on V. cholerae CFUs. Underwater capillary discharge is an efficient approach for the inactivation of V. cholerae from drinking water.

Numerical Analysis of Hydrogen Peroxide Addition and Oxygen-Enriched Methane Combustion.

Methane (CH4)/air lean combustion can be enhanced by increasing the concentration of the oxidizer, like oxygen (O2) enrichment, or adding a strong oxidant to the reactant. Hydrogen peroxide (H2O2) is a strong oxidizer that yields O2, steam, and appreciable heat after decomposition. This study numerically investigated and compared the effects of H2O2 and O2-enriched conditions on the adiabatic flame temperature, laminar burning velocity, flame thickness, and heat release rates of CH4/air combustion using the San Diego mechanism. The result showed that in fuel-lean conditions, the adiabatic flame temperature changed from H2O2 addition > O2-enriched scenario to O2-enriched scenario > H2O2 addition with increasing α. This transition temperature was not affected by the equivalence ratio. Adding H2O2 enhanced the laminar burning velocity of the CH4/air lean combustion more than the O2-enriched scenario. The thermal and chemical effects are quantified in various H2O2 additions, and it is found that the chemical effect has a noticeable contribution to the laminar burning velocity compared with the thermal effect, especially in higher H2O2 addition. Further, the laminar burning velocity had a quasi-linear correlation with (OH)max in the flame. The maximum heat release rate was observed at lower temperatures for H2O2 addition and higher temperatures for the O2-enriched scenario. The flame thickness was significantly reduced upon adding H2O2. Finally, the dominant reaction to the heat release rate changed from the reaction of CH3 + O ↔ CH2O + H in the CH4/air or O2-enriched scenario to the reaction of H2O2 + OH ↔ H2O + HO2 in the H2O2 addition scenario.

Hydrogen peroxide enhanced photoinactivation of Candida albicans by a novel boron-dipyrromethene (BODIPY) derivative.

Photodynamic inactivation (PDI) has received increasing attention as a promising approach to combat Candida albicans infections. This study aimed to evaluate the synergistic effect of a new BODIPY (4,4-difluoro-boradiazaindacene) derivative and hydrogen peroxide on C. albicans. BDP-4L in combination with H2O2 demonstrated enhanced photokilling efficacy. In suspended cultures of C. albicans, the maximum decrease was 6.20 log and 2.56 log for PDI using BDP-4L (2.5μM) with or without H2O2, respectively. For mature C. albicans biofilms, 20μM BDP-4L plus H2O2 eradicated C. albicans, causing an over 6.7 log count reduction in biofilm-associated cells, while only a reduction of ~ 1 log count was observed when H2O2 was omitted. Scanning electron microscopy analysis and LIVE/DEAD assays suggested that PDI using BDP-4L plus H2O2 induced more damage to the cell membrane. Correspondingly, amplification of nucleic acids release was observed in biofilms treated with the combined PDI. Additionally, we also discovered that the addition of hydrogen peroxide potentiated the generation of 1O2 in PDI using the singlet oxygen sensor green probe. Collectively, BDP-4L combined with H2O2 presents a promising approach in the treatment of C. albicans infections.

Synthesis and Characterization of Humic/Melanin-like Compounds by Oxidative Polymerization of Simple Aromatic Precursors

Dissolved organic matter (DOM) is a complex mixture of naturally occurring organic molecules originating from multiple marine and terrestrial sources. DOM plays a significant role in water quality by affecting the photochemistry, trace metal transport, and acidity in aquatic systems. Understanding the chemical composition of DOM helps interpret the links between its optical properties and molecular structures. Currently, the molecular origins of the optical properties of DOM are not well-defined. In this study, we oxidize and initiate the polymerization of melanin precursors 1,8-dihydroxy naphthalene and 5,6-dihydroxy indole by the addition of hydrogen peroxide and/or with ultraviolet irradiation. Our goal is to evaluate the possibility of reproducing the optical signatures of DOM from simple aromatic precursors. Optical characterization shows an extreme shift of the absorbance to a featureless trend and broad fluorescence peaks (350–500 nm) like DOM. Electrospray ionization (ESI) and matrix-assisted laser desorption ionization (MALDI) mass spectrometry show evidence of oligomers with varying degrees of oxidation. The combination of our results shows that about 1–4 units of melanin oligomers with varying degrees of oxidation mimic the optical properties of DOM. Overall, our results strongly support the idea that simple precursors form oligomeric chromophores mimicking DOMs optical properties through simple oxidative steps.

Metformin reverses oxidative stress‑induced mitochondrial dysfunction in pre‑osteoblasts via the EGFR/GSK‑3β/calcium pathway.

Oxidative stress is one of the main causes of osteoblast apoptosis induced by post‑menopausal osteoporosis. The authors previously found that metformin can reverse the loss of bone mass in post‑menopausal osteoporosis. The present study aimed to further clarify the effects and mechanisms of action of metformin in post‑menopausal osteoporosis under conditions of oxidative stress. Combined with an in‑depth investigation using the transcriptome database, the association between oxidative stress and mitochondrial dysfunction in post‑menopausal osteoporosis was confirmed. A pre‑osteoblast model of oxidative stress was constructed, and the apoptotic rate following the addition of hydrogen peroxide and metformin was detected using CCK‑8 assay and Annexin V‑FITC/PI staining. Mitochondrial membrane potential was detected using the JC‑1 dye, the intracellular calcium concentration was detected using Fluo‑4 AM, the intracellular reactive oxygen species (ROS) level was observed using DCFH‑DA, and the mitochondrial superoxide level was observed using MitoSOX Red. Bay K8644 was used to increase the level of intracellular calcium. siRNA was used to interfere with the expression of glycogen synthase kinase (GSK)‑3β. Western blot analysis was used to detect the expression of mitochondrial dysfunction‑related proteins. The results revealed that oxidative stress decreased mitochondrial membrane potential and increased intracellular ROS, mitochondrial superoxide and cytoplasmic calcium levels in pre‑osteoblasts; however, metformin improved mitochondrial dysfunction and reversed oxidative stress‑induced injury. Metformin inhibited mitochondrial permeability transition pore opening, suppressed the cytoplasmic calcium influx and reversed pre‑osteoblast apoptosis by promoting GSK‑3β phosphorylation. Moreover, it was found that EGFR was the cell membrane receptor of metformin in pre‑osteoblasts, and the EGFR/GSK‑3β/calcium axis played a key role in metformin reversing the oxidative stress response of pre‑osteoblasts in post‑menopausal osteoporosis. On the whole, these findings provide a pharmacological basis for the use of metformin for the treatment of post‑menopausal osteoporosis.

Effective and Efficient Porous CeO2 Adsorbent for Acid Orange 7 Adsorption.

A porous CeO2 was synthesized following the addition of guanidine carbonate to a Ce3+ aqueous solution, the subsequent addition of hydrogen peroxide and a final hydrothermal treatment. The optimal experimental parameters for the synthesis of porous CeO2, including the amounts of guanidine carbonate and hydrogen peroxide and the hydrothermal conditions, were determined by taking the adsorption efficiency of acid orange 7 (AO7) dye as the evaluation. A template-free hydrothermal strategy could avoid the use of soft or hard templates and the subsequent tedious procedures of eliminating templates, which aligned with the goals of energy conservation and emission reduction. Moreover, both the guanidine carbonate and hydrogen peroxide used in this work were accessible and eco-friendly raw materials. The porous CeO2 possessed rapid adsorption capacities for AO7 dye. When the initial concentration of AO7 was less than 130 mg/L, removal efficiencies greater than 90.0% were obtained, achieving a maximum value of 97.5% at [AO7] = 100 mg/L and [CeO2] = 2.0 g/L in the first 10 min of contact. Moreover, the adsorption-desorption equilibrium between the porous CeO2 adsorbent and the AO7 molecule was basically established within the first 30 min. The saturated adsorption amount of AO7 dye was 90.3 mg/g based on a Langmuir linear fitting of the experimental data. Moreover, the porous CeO2 could be recycled using a NaOH aqueous solution, and the adsorption efficiency of AO7 dye still remained above 92.5% after five cycles. This study provided an alternative porous adsorbent for the purification of dye wastewater, and a template-free hydrothermal strategy was developed to enable the design of CeO2-based catalysts or catalyst carriers.

Plywood for Construction Purposes on a Phenol-Formaldehyde Binder Modified with Hydrogen Peroxide

Reducing the pressing temperature of plywood on the FF binder allows you to reduce its cost, but at the same time, the physical and mechanical characteristics of plywood deteriorate. Modification of the phenol-formaldehyde binder with hydrogen peroxide reduces the curing time of the phenolic binder, the pressing temperature of the FSF plywood, and improves the physical and mechanical properties of the FSF plywood. Regression models have been developed for dependence of the plywood strength during cleavage along the adhesive seam, strength during static bending, and thickness swelling after 24 hours in water on the factors varied in the experiment – the proportion of hydrogen peroxide addition and the pressing temperature. The IR spectra of plywood allow us to estimate the effect of H2O2 on the bonds involved in the structure formation of material. With the addition of hydrogen peroxide, the number of active methylene groups decreases, which indicates an increase in degree curing of modified binder.

The effect of protein oxidation on the formation of advanced glycation end products after chicken myofibrillar protein glycation

Investigation that protein oxidation to the formation of advanced glycation end products (AGEs) after chicken myofibrillar protein glycation is limited. Models of protein oxidation induced by different concentrations of hydroxyl radicals (·OH) were developed after the chicken myofibrillar protein mild glycation (MPG). Results exhibited that levels of AGEs and surface hydrophobicity (H0) steadily increased with the addition of hydrogen peroxide (H2O2) concentration. However, levels of sulfhydryl group, free amino group, and particle size gradually decreased with the H2O2 concentration. The protein carbonyl value increased in H2O2 concentration until 10 mmol/L. Pearson’s correlation indicated that MPG structure modification (unfolding and degradation) induced by protein oxidation were significantly positively correlated with AGEs concentration (P < 0.05). Finally, a mechanism was proposed to hypothesize the effect of protein oxidation on the formation of AGEs under MPG conditions.

Effects of sodium persulfate and hydrogen peroxide on imidazolium ionic liquid degradation by simulated solar light in aqueous ZnO suspension

AbstractThe degradation of an ionic liquid: hexyl methyl imidazolium chloride (HMImCl) in the systems of simulated solar light/ZnO and simulated solar light/ZnO/oxidant (i.e., H2O2 and S2O82−) were investigated in aqueous solution. The influences of different variables such as catalyst concentration, hydrogen peroxide, and persulfate dosage on HMImCl photocatalytic degradation were determined. It was found that the adsorption of HMImCl on the catalyst surface was insignificant. The photocatalytic degradation of HMImCl followed pseudo first‐order kinetics, and the rate constant at natural pH (pH 7.2) was 11.8 × 10−2 min−1. The addition of hydrogen peroxide to the process not only does not enhance the degradation rate of HMImCl but also decreases kapp significantly with [HMImCl] = 3×10−5 mol L−1, oxidant concentration (in the range of 5 × 10−5–10−1 mol L−1), and catalyst concentration of 1 g L−1. The results elucidated that the use of Na2S2O8 (in the range of 10−4–10−2 mol L−1) strongly enhances the degradation rate of HMImCl compared with photocatalytic process of the catalyst.

Scalable preparation of high-quality graphene by electrochemical exfoliation: effect of hydrogen peroxide addition

Scalable preparation of high-quality graphene by electrochemical exfoliation: effect of hydrogen peroxide addition

UVC-Assisted Tertiary Treatments for the Removal of Pollutants of Emerging Concern in Real WWTP Matrices

The aim of this work is to investigate the enhancement of UVC-based tertiary treatments; for this purpose, real wastewater treatment plant (WWTP) effluent was spiked with a model pollutant, namely acetaminophen. UVC irradiation resulted in some photodegradation of the acetaminophen, which was enhanced upon the addition of hydrogen peroxide (11 mM), but higher amounts of this oxidizing agent resulted in no significant acceleration of the process. An experimental design methodology based on Doehlert matrices showed the significance of hydrogen peroxide concentration and the flow rate for the reactor operating in continuous mode. The addition of low amounts of iron had a positive influence on the process, most probably due to a photo-Fenton-like process using the complexing ability of organic matter. For effluents with higher turbidity, a strategy combining coagulation-flocculation with UVC irradiation was tested: this approach was meaningful as flocculation-coagulation decreased water turbidity and resulted in a more efficient acetaminophen removal. However, under those conditions, the presence of iron did not show a positive role, most probably because of the absence of organic matter, which makes the UVC/H2O2 process more efficient and, on the other hand, humic-like substances available to complex iron to drive a neutral photo-Fenton process.

Sulfide Removal by Catalitic Oxidation From Rayon Waste

Catalytic oxidation of spent sulfidic caustic consist of SH- ion or NaHS compound by H 2 O2 in neutral or acidic solution to elemental sulphur may provide a convenient and economical method for the control of sulphide wastes and their associated odors at pulp, paper and textile industry. Oxidation of sulfide in rayon waste by hydrogen peroxide was investigated in the presence of ferric sulfate catalyst. Kinetic equations and activation energies of H 2 O2 and SH- ion to total sulphur and sulphate in rayon waste for catalytic oxidation reaction were calculated based on the experimental results. For the removal of sulfide from sulfide solution the most common process involves its catalytic oxidation to a more benign form sulfate. The rate of sulfidic catalytic oxidation was found higher at lower initial sulphide concentration and the rate of sulphide catalytic oxidation was found directly proportional to loading and hydrogen peroxide addition. Optimum total sulphide concentration was achieved when sulphide solutions in the presence of H 2 O 2 in the ratios SH-/H 2 O 2 1:4.2. The potential user of H 2 O 2 determine the optimal conditions for control of odor, corrosion and waste treatment cost due to sulfide consisting of sulphur ion, sulphate ion, etc. The catalytic oxidation of sulphides into sulphates by H 2 O 2 may be applied directly to aqueous wastes containing these odorants

Development of Alkali-Activated Porous Concrete Composition from Slag Waste

In this paper, a porous alkali-activated slag concrete was developed that can be used in the construction sector as a sustainable building material and potentially as an alternative to the aerated concrete products currently on the market. Ferrous slag from the metallurgical industry (Finland) and phosphogypsum from a fertilizer plant (Lithuania) were used as precursors in alkali-activated systems. The addition of hydrogen peroxide and phosphogypsum led to positive changes in the final properties of the test material. Porous concrete based on alkali-activated slag was analyzed by X-ray diffraction (XRD), Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) methods. The compressive strength, density, thermal conductivity and porosity of the hardened specimens were evaluated as well. Research is being conducted with the material in question to create a cheap, particularly low-energy demanding building material. This material must have suitable mechanical properties for the structure and, at the same time, suitable thermal conductivity properties. It was determined that this porous concrete had compressive strength in the range of 2.12-7.95 MPa, density from 830 kg/m3 to 1142 kg/m3, and thermal conductivity in the range of 0.0985-0.2618 W/(m·K). The results indicate that the recommended content of phosphogypsum in alkali-activated material is 3-5% due to the optimal distribution of the mechanical and thermal properties and the conductivity. Alkali-activated slag and phosphogypsum material can be used in the manufacture of low-strength insulation blocks and to protect structures from the effects of high temperatures.

Mitigation of the Toxicity of Capsaicin on Anaerobic Codigestion of Food Waste and Waste Activated Sludge Using Calcium Peroxide: A Comprehensive Analysis Using Computational and Biological Approaches

Increasing amounts of food waste with high concentrations of capsaicin are generated globally. Capsaicin concentration has been proven to inhibit methane production in the anaerobic codigestion process; thus, strategies to alleviate this toxicity are urgently needed. This study focuses on the use of calcium peroxide for alleviating the inhibitory effect of capsaicin and methane production promotion in anaerobic codigestion for the first time. Results show that calcium peroxide increases the rate of capsaicin degradation significantly. Based on active site prediction, degradation product identification, and density functional theory calculations, the main pathways of capsaicin degradation are verified to be O-demethylation and hydrogen abstraction. According to the quantitative structure–activity relationship, the main degradation products are less toxic than capsaicin. With an increase of calcium peroxide addition from 0 to 0.10 g/g VS (volatile solid), the methane yield and production rate are promoted from 174.92 ± 7.12 mg/g VS and 10.54 ± 0.32 mL/(g VS·d) to 307.56 ± 10.43 mg/g VS and 23.15 ± 0.72 mL/(g VS·d), respectively. This study provides insights into calcium peroxide-enhanced capsaicin degradation and demonstrates an effective niche to mitigate the capsaicin toxicity toward anaerobic codigestion.

Synthesis of cuprous oxide via ion exchange route for photocatalytic degradation of methylene blue

Abstract Cuprous oxide (Cu2O) nanoparticles were successfully synthesized using cupric hydroxide gel as a precursor and glucose as a reductant. A well-dispersed cupric hydroxide gel was prepared by treatment of aqueous cuprous chloride with anion exchange resin. The average diameter of the Cu2O nanoparticles was 780 nm. Attenuated total reflectance Fourier transform infrared spectroscopy showed that polyethylene from the anion exchange resin was present in the Cu2O powder, explaining how the ion exchange route reduces agglomeration of the Cu2O nanoparticles. Addition of hydrogen peroxide during the photocatalytic degradation of methylene blue significantly reduced photocorrosion of the Cu2O nanoparticles. The mechanism by which hydrogen peroxide participates in the photocatalytic process and inhibits photocorrosion was investigated.