Concentration Of H2O2 Solution Research Articles

Effect of H2O2 Treatment on Mechanical and Mechanochemical Properties of Fused Silica

The surface properties of fused silica (FS) change after H2O2 treatment, but the surface and subsurface damage behaviors and their mechanisms under various physical contact conditions have not been elucidated yet. This work investigated the effect of H2O2 treatment on mechanical and mechanochemical properties of FS surface. The results show that the hydrophilicity and adsorbed water film thickness of the FS surface increase with the concentration of H2O2 solution. The surface damage, nanowear, and subsurface deformation of FS caused by indentation increase with the concentration of H2O2 solution, while the nanohardness and reduced modulus decrease. Further analysis revealed that the water activity on the FS surface plays a critical role in reducing the mechanical and mechanochemical properties. In addition, the treatment with H2O2 solution on the FS surface shows a weakly corrosive effect, which implies the H2O2 treatment can be an alternative method to remove the surface defects on FS optics.

Hydrogen peroxide reduces sensitivity to aluminum in canola?

The objective of this study was to evaluate the effect of aluminum and the mitigating potential of H2O2 on the stress and antioxidant responses in canola (Brassica napus var. oleifera (Moench) Delile) affecting the emergence and initial growth of plants. Canola seeds, cultivar Hyola 61, were treated with different concentrations of H2O2 solution (0.0, 0.075, and 0.15 M), and later sown under different concentrations of aluminum (0.0, 10, 20, and 30 mmolc dm-3). After 20 days of plant emergence, survival and growth characteristics were evaluated. 20, 30, 40, 50, and 60 days after emergence, height, chlorophyll index, chlorophyll a fluorescence, and the activity of superoxide dismutase in the roots were determined. The canola is sensitive to aluminum, and the treatment of seeds with H2O2 0.15 M mitigated the stress caused by the highest dose of aluminum. H2O2 treatment enabled high emergence but did not favor seedling survival or growth. The H2O2 did not increase SOD activity. The chlorophyll a fluorescence characteristics proved the sensitivity of canola to aluminum, but the presence of H2O2 maintained the stability and functionality of photosystem II.

A Magnetocatalytic Propelled Cobalt–Platinum@Graphene Navigator for Enhanced Tumor Penetration and Theranostics

A Magnetocatalytic Propelled Cobalt–Platinum@Graphene Navigator for Enhanced Tumor Penetration and Theranostics

Effects of hydrogen peroxide solution on the biomechanics of porcine cornea.

To determine the biomechanical changes of porcine corneas after the application of hydrogen peroxide(H2O2) solution. Fifty-five porcine eyeballs with similar sizes were divided into 11 groups based on the H2O2 application. The eyeballs were treated with the following concentrations of H2O2 solution: 1 mol/L, 500 mmol/L, 250 mmol/L, 125 mmol/L, 62.5 mmol/L, 31.25 mmol/L, 15.63 mmol/L, 7.81 mmol/L, 3.91 mmol/L, 0.9% saline, or blank. The eyeballs were immersed into the solution for 30 min. The biomechanics of each cornea in the different groups was determined soon after the indentation and tensile tests. We calculated the average Young's modulus of the different groups to determine the effects of H2O2 solution on porcine corneas. The comparison between the groups was conducted using ANOVA analysis. Moreover, the safety of each concentration of H2O2 solution on the corneal tissues was determined by histopathological examination. The Young's modulus was significantly different among all the groups (p = 0.003). The modulus was the highest in the group treated with 3.91 mmol/L H2O2 and it was significantly different from that in the group treated with 0.9% saline or the blank group, for both the indentation and tensile tests. Histopathological examination showed that H2O2 at a concentration of ⩾62.5 mmol/L damaged the epithelium, stroma, or both, while H2O2 at a concentration ⩽31.25 mmol/L did not change the morphology of the epithelium or stroma. Treatment with 3.91 mmol/L H2O2 solution can safely and effectively increase the biomechanical strength of the cornea.

Feasibility of Paper Production from Oil Palm Trunk Using Arrowroot Flour as a Binder

Oil palm trunk is lignocellulose biomass and agricultural residual waste that has not been utilized to its maximum potential. The feasibility of paper production from oil palm trunk (OPT) was studied for one alternative application. OPT was treated with 8% (w/v) alkaline solution (NaOH), subsequently with a different concentration of H2O2 solution (2, 4, 6 and 8% w/v). The results showed that the brown color of OPP was converted to a pale yellow color after bleaching with H2O2 while hemicellulose and lignin were also removed. Arrowroot flour was used as a binder for mold oil palm paper. The optimum condition for oil palm paper production was 15% (w/v) NaOH for 60 min then 6 % (v/v) H2O2 for 30 min. The obtained OPP paper showed a density of 183.53 ± 1.86 g/cm3, a water absorption of 0.0904 ± 0.0010 mL/cm2, a tensile index of 2.60 ± 0.07 Nm/g and a burst index of 1.22 ± 0.04 kPa m2/g. All value properties of the obtained OPP paper showed that the OPP value was lower than that of available commercial Kraft paper (KI125 and KT125). Meanwhile, this OPP paper process could continuously improve to be a container formation.

Effects of energy and hydrogen peroxide concentration on structural and optical properties of CuO nanosheets prepared by pulsed laser ablation

Laser ablation of copper targets using Ce:Nd:YAG laser with pulses of 1064 nm wavelengths at 10 ns pulse width and with different laser pulse energies and in different concentrations of H2O2 solution is investigated experimentally. Cu/CuO flake-like nanostructures with visible band gap and the extension of its light absorption by changing the synthesis parameters such as laser pulse energy and concentration of H2O2 solution were observed.Characterization and comparison of the obtained suspensions are exploited by X-ray diffraction (XRD), UV–vis spectroscopy and field emission scanning electron microscopy (FE-SEM). The XRD analysis data show that in 10 vol% H2O2 solution CuO phase has been synthesized, while with decreasing the H2O2 concentration, Cu phase is also observed. The mean crystallite sizes of CuO were estimated using XRD patterns and were between 2.1 and 3.3 nm. The comparison of the UV–visible absorption spectra indicates that with decreasing pulse energy and decreasing H2O2 concentration up to 5 vol% the band gap of nanoparticles increased from 2.19 eV to 2.34 eV, which is accordant with the quantum confinement effect. FESEM image of all the synthesized samples illustrate the formation of flake-like nanostructure with the thickness of about 12–15 nm.

MiR‑370 inhibits the oxidative stress and apoptosis of cardiac myocytes induced by hydrogen peroxide by targeting FOXO1

Myocardial infarction, one of the main factors that threatens human health, leads to cardiac cell death. Myocardial cells suffer ischemia and hypoxia for a long period of time, which can lead to irreversible cell death or apoptosis and cardiac dysfunction. MicroRNAs (miRs) have been reported to play an important role in a wide range of biological processes in cardiac myocytes, which respond to inflammation and oxidative stress. The aim of the present study was to investigate the effect of miR-370 on oxidative stress and apoptosis of cardiac myocytes in ischemic H9C2 cells induced by hydrogen peroxide (H2O2). H9C2 cells were cultured and treated with different concentrations of H2O2 solution. Then, cells were transfected with miR-370 mimic or negative control (NC) mimic, small interfering (si)-RNA-Forkhead box O1 (FOXO1) and NC siRNA. A Cell Counting Kit-8 and flow cytometry assay were conducted to detect cell viability and cell apoptosis. The expression of oxidative stress associated factors were detected by ELISA. The levels of miR-370 and FOXO1 were examined using western blotting and reverse transcription-quantitative PCR. A luciferase reporter gene assay was performed to verify whether FOXO1 was a target gene of miR-370. The results revealed that miR-370 expression was downregulated and FOXO1 expression was increased in H9C2 cells induced by H2O2. Additionally, FOXO1 was proven to be a target of miR-370. The ELISA and flow cytometry assay revealed that miR-370 overexpression and FOXO1 silencing reversed H2O2-induced oxidative stress and apoptosis. The results indicated that miR-370 could inhibit the oxidative stress and apoptosis of H9C2 cells induced by H2O2 by targeting FOXO1. Therefore, miR-370 may be a new therapeutic target for ischemic heart disease.

Characterization, antioxidant and hypoglycemic activities of degraded polysaccharides from blackcurrant (Ribes nigrum L.) fruits

In this study, the degradation of polysaccharides from blackcurrant (BCP) was investigated. Two low-molecular-weight polysaccharides (DBCP-1, DBCP-2) were obtained using Fe2+ with different concentrations of H2O2 solution. IR spectra showed DBCPs had obvious characteristic peaks of polysaccharides. GC analysis confirmed DBCPs were composed of the same monosaccharide units as BCP but with different molar ratios. NMR analysis indicated DBCPs and BCP had similar glycosidic linkage patterns. The surface area of fragmented structure in DBCPs was reduced compared to BCP, and they had no triple helix structure. The results of bioactivity assays indicated that DBCPs exhibited higher antioxidant, α-amylase and α-glucosidase inhibitory activities than BCP, and the degraded polysaccharides with the lower molecular weight possessed higher bioactivities. These results suggested that Fe2+-H2O2 degradation did not change the main structure of polysaccharide and the degree of degradation could play a key role in the bioactivities of the polysaccharides.

(Invited) Fabrication and Dielectric Properties of BaTiO3 Thin Films on Polycrystalline Ni Foils

The BaTiO3 (BTO) thin films were deposited on polycrystalline Ni foils using a chemical solution approach. We show that the interface between the BTO film and the Ni foil plays a critical role in determining the dielectric and magnetoelectric (ME) properties of this flexible assembly. A pretreatment process of nickel foils with hydrogen peroxide (H2O2) solution has been conducted to form thin nickel oxide layers on the surfaces for the growth of BTO films. Both the concentration of H2O2 solution and the pretreated time were found to strongly affect the dielectric constant of BTO films, which is likely to be related to the evolution of nickel oxide at the interface during the growth of BTO films. The growth dynamics was systematically studied to optimize the single phase BTO films with good dielectric properties. Our results have demonstrated that not only a well-controlled interface between the BTO film and the Ni substrate can be achieved, but also an good dielectric and ME performance can be accomplished.

Characterization and antioxidant activities of degraded polysaccharides from Poria cocos sclerotium

Poria cocos F.A.Wolf is a Chinese traditional medicine used to treat chronic gastritis, edema, nephrosis, gastric atony, and acute gastroenteric catarrh. Polysaccharides are the main active component of P. cocos. We obtained polysaccharides PCP-1, PCP-2, and PCP-3 from the degradation of P. cocos polysaccharides (PCP) with different concentrations of H2O2 solution. Molecular weights were determined by high performance size exclusion chromatography. HPLC analysis of monosaccharide composition confirmed that PCP-1, PCP-2, and PCP-3 are heteropolysaccharides composed of glucose and arabinose. IR spectra indicated obvious characteristic peaks of polysaccharides. The antioxidant activities of these polysaccharides were evaluated by established in vitro systems, including scavenging activity of hydroxyl radicals, ABTS radicals, and ferrous ions. The degradation polysaccharides exhibited obvious and concentration-dependent antioxidant properties. In addition, DNA binding analysis showed that PCP-1 had a stronger capacity than other polysaccharides to interact with DNA. However, each polysaccharide had a certain capacity for DNA damage protection.

Growth Dynamics of Barium Titanate Thin Films on Polycrystalline Ni Foils Using Polymer-Assisted Deposition Technique

Polymer-assisted deposition (PAD) technique was developed to fabricate ferroelectric BaTiO(3) (BTO) thin films directly on polycrystalline nickel foils. The growth dynamics was systematically studied to optimize the single-phase BTO films with good dielectric properties. It is critical to pretreat nickel foils with hydrogen peroxide (H(2)O(2)) solution to form thin nickel oxide layers on the surfaces for the growth of BTO films. Both the concentration of H(2)O(2) solution and the pretreated time were found to strongly affect the dielectric constant of BTO films, which may be associated with the oxygen diffusion from nickel oxide buffer layers to BTO layers during annealing. The BTO thin films with optimized growth conditions have good crystal structure and electrical properties, suggesting that the as-grown BTO films by PAD technique can be utilized for new devices development and energy storage applications.

Study on Wear Behaviour of Ceramics/1Cr18Ni9Ti Wear Components in H<sub>2</sub>O<sub>2</sub> Solution

The wear performances of three types of ceramics (ZrO2, Al2O3, Si3N4)/1Cr18Ni9Ti stainless steel rubbing pairs were analyzed under 0% (pure water), 10%, 30%, 50%, 70% and 90% hydrogen peroxide (H2O2) solution. The results showed that, under different concentrations of H2O2 solution, the worn surface roughness of the 1Cr18Ni9Ti stainless steel was bigger than that under pure water when the counterpart was ZrO2 ceramic ball, while the worn surface roughness of the 1Cr18Ni9Ti stainless steel was smaller than that under pure water when the counterpart was Al2O3 ceramic ball. For the ZrO2, Al2O3, Si3N4 ceramics ball, the average worn surface roughness of Al2O3 ceramic ball was the smallest, and the average worn surface roughness of Si3N4 ceramic ball was the biggest. When the concentration of H2O2 solution was 10%, the metal particles from the ZrO2/1Cr18Ni9Ti and Al2O3/1Cr18Ni9Ti stainless steel rubbing pairs had the features with large size and bright surface. The surfaces of the metal particles were oxidized clearly when the concentrations of H2O2 solution were 70% and 90%.

A Study on a Surface Preparation Method for Single-Crystal SiC Using an Fe Catalyst

In this study we investigated the possibility of removing and flattening a single-crystal silicon carbide (SiC) surface by a novel polishing method utilizing hydroxyl radicals (OH radicals) generated on an Fe catalyst surface. To demonstrate the feasibility of preparing a smooth SiC surface, an Fe catalyst and a SiC substrate were rubbed together in H2O2 solution, and then the area on the SiC surface that had come into contact with the Fe catalyst was observed in detail. The removal depth and surface microroughness were measured and evaluated using a phase-shift interference microscope and an atomic force microscope (AFM), respectively. Moreover, the removal of material from the SiC surface by utilizing an Fe catalyst rod was examined. The obtained results show that the hard SiC surface can be effectively polished and that the processed area on the SiC surface has atomic-level smoothness along the sliding direction. Moreover, it is shown that the removal characteristics of the SiC substrate depend on process parameters such as the process time, rotation speed, contact load, and concentration of H2O2 solution. These results provide useful information for preparing an atomically smooth SiC surface.

Biochemical sniffer for odourless hydrogen peroxide vapour

A biochemical gas-sensor (bio-sniffer) was constructed for convenient measurement of odourless hydrogen peroxide (H2O2) vapour, which is harmful to skin and mucous membranes. An enzyme-immobilized membrane was fabricated by spreading the mixture of catalase and photo-crosslinkable polymer on a dialysis membrane. An H2O2 biosensor was constructed by attaching this catalase-immobilized membrane to the sensitive top of a Clark-type oxygen electrode, and the oxygen generation from the decomposition of H2O2 catalysed by catalase was measured amperometrically. This biosensor was first applied to the measurement of H2O2 solution and was able to quantify the concentrations of H2O2 solution from 0.02 to 10.0 mmol L−1. Then, this biosensor was applied to gaseous phase as a bio-sniffer and was able to detect the odourless H2O2 vapour with the calibration range from 0.5 to 30 ppm, where the threshold limit value assigned by the American Conference of Governmental Industrial Hygienists (1 ppm) is covered.

Thermochemical Treatment of Radiata Pine (Pinus radiata) Bark with Hydrogen Peroxide Solutions at Temperatures Higher than 100 °C

Abstract Radiata pine bark was treated with 0—15% hydrogen peroxide (H2O2) solutions at temperatures higher than 100 °C, and fractionated into water soluble, insoluble, and gas fractions. The distribution of these fractions was calculated on the basis of weight and carbon content, and compared with the aim of finding the optimum conditions for efficiently obtaining water-soluble materials for producing wood adhesives. The yield of water-soluble materials was significantly dependent on the temperature and the concentration of H2O2 solution. The highest yields of water-soluble materials (47.4 and 47.9% on the basis of weight and carbon content, respectively) were obtained with 15% H2O2 solution at 120 °C. The yield increased with increasing temperature up to 120 °C and then decreased at higher temperatures. Under the latter conditions, gases such as CO2 and CO were generated. When the bark was treated with 15% H2O2 solution at 140 °C, an exothermic reaction took place and 47.4% of the carbon of the bark was converted into gases. At the same time, most of the H2O2 was decomposed. The water-soluble fraction mainly consisted of low molecular weight acidic components, which are degaradated and oxygenated products of lignin and polyflavanoids. This bark solubilization process consists of very complicated combinations of various reactions. Many organic compounds, other than acids, might be present in the water-soluble fraction. The water-insoluble material is the oxygenated cellulose compound.