Amount Of H2O2 Research Articles

Graphene-anchored conductive polymer aerogel composite for the electrocatalytic detection of hydrogen peroxide and bisphenol A

An aerogel composite of reduced graphene oxide (rGO) anchored on amine groups of conductive polyterthiophene (p(APT-rGO) aerogel is synthesized for the first time, using a hydrothermal method. The electrocatalytic performance of the composite electrode was explored for bisphenol A (BPA) oxidation and hydrogen peroxide reduction. The surface of catalyst was found to possess numerous active sites owing to exposed edges and large surface area of a three-dimensional aerogel. Additionally, incorporation of rGO into poly(aminopyrimidyl terthiophene) (pAPT) is found to enhance the catalytic performance and stability. The p(APT-rGO) aerogel coated screen printed carbon electrode (SPCE) displayed a superior catalytic performance for the BPA detection with two dynamic ranges of 5–500 nM and 1–200 µM with the detection limit of 4.28 ± 0.75 nM. Otherwise, the dynamic ranges of H2O2 detection were 100 nM-100 µM and 200 µM-3 mM with the detection limit of 9.12 ± 1.03 nM. The catalytic active site of the composite aerogel was investigated for BPA oxidation and H2O2 reduction. The proposed sensor demonstrated an excellent analytical performance for the determination of BPA extracted from commercial polycarbonate bottles and trace amounts of H2O2 released from living cells by drug stimulation.

A Fe(III)-porphyrin-oxaliplatin(IV) nanoplatform for enhanced ferroptosis and combined therapy.

Since there are several limitations in cancer treatment for traditional chemotherapy, such as side effects, poor prognosis and drug resistance, developing new combined therapy is urgently needed. In this work, a biocompatible, simple and tumor microenvironment-responsive nanotheranostics (PCN-Oxpt/PEG) was built to favor the chemotherapy/ferroptosis/immunomodulation synergism in cancer. This nanotheranostics is constructed by modifying oxaliplatin prodrug and PEG on Fe(III)-porphyrin metal-organic frameworks (PCN(Fe) MOFs). After intravenous injection, the cloak of PEG leads to long circulation, and the Fe(III)-porphyrin MOFs enables dual-model guidance with fluorescence (FL) and magnetic resonance imaging (MRI). Inside the tumor, the intracellular H2O2 would be transferred into hydroxyl radicals (•OH) by iron ions released from MOFs, which could trigger the lethal ferroptosis to cancer cells. Meanwhile, oxaliplatin(II) transformed from the loaded oxaliplatin prodrug would result in the chemotherapy, as well as immunogenic cell death (ICD), and the prodrug strategy could also avoid the occurring of liver damage by the direct administration of oxaliplatin(II). It was noticed that the ferroptosis effect was enhanced by triple-assistance during the combined therapy, as followed: (1) glutathione (GSH) would be consumed in the process of oxaliplatin(II) generation from oxaliplatin prodrug; (2) the increased CD8+ T cells induced by ICD were able to produce interferon-γ (IFN-γ), which could inhibit the transport of cystine by tumor cells, and impair the activation of glutathione peroxidase 4 (GPX4); (3) the amount of H2O2 could be increased by the internalized oxaliplatin and thus further promote the Fenton reaction and ferroptosis. Both in vivo and in vitro results revealed that tumor growing was significantly inhibited by PCN-Oxpt/PEG, taken together, the concomitant of oxaliplatin-mediated chemotherapy and ICD with triple-enhanced ferroptosis offer great prospect in the clinical treatment of cancer.

Physiological and Biochemical Effects of Drought Stress in Stevia (Stevia rebaudiana Bertoni)

Kuraklık son yıllarda endişe verici bir şekilde artmakta olup tarımsal ürünlerin verimliliğini sınırlandırmaktadır. Bu durum, kurak koşullara dayanıklı bitkilerin tespit edilmesine yönelik araştırmaların önemini artırmıştır. Bu çalışmada, Stevia rebaudiana Bertoni bitkisine ait iki çeşidin (Yalova ve STF-4) kuraklık stresi altında fizyolojik ve biyokimyasal tepkileri araştırılmıştır. Bitkiler kontrollü sera koşullarında 3 ay boyunca yetiştirilmiş ve sonrasında 3 hafta boyunca kuraklığa maruz bırakılmıştır. Üç hafta sonunda hasat edilen bitkilerden yaprak uzunluğu, ozmotik potansiyel, nisbi su içeriği (RWC), klorofil floresansı (Fv/Fm), prolin miktarı, hidrojen peroksit (H2O2) miktarı ve lipid peroksidasyonu seviyesi ölçülmüştür. S. rebaudiana bitkisinin her iki çeşidinde de kuraklık stresi altında kontrol grubundaki bitkiler ile kıyaslandığında yaprak uzunluğunda azalma belirlenirken en çok azalma Yalova çeşidinde (%25,7) saptanmıştır. Bununla birlikte, her iki çeşit de kuraklık stresi altında su durumlarını korumuşlardır. Fv/Fm değeri STF-4 çeşidinde kuraklıktan etkilenmezken Yalova çeşidinde kontrole oranla düşüş göstermiştir. Prolin miktarında ise çeşitler arasında fark kaydedilmiştir. Kurak koşullar altında STF-4 çeşidinde prolin miktarında değişim gözlenmezken Yalova çeşidinde %42,9 artış meydana gelmiştir. Diğer taraftan, kuraklık stresi, yapraklardaki lipid peroksidasyon seviyesini önemli ölçüde arttırmıştır. Bu artış, Yalova çeşidinde %41,2 iken STF-4 çeşidinde %21,1 olarak belirlenmiştir. İki çeşit arasında kuraklık stresine karşı farklı tepki H2O2 içeriğinde gözlenmiştir. Kuraklık stresi altında H2O2 miktarı Yalova çeşidinde %42,7 oranında azalırken STF-4 çeşidinde %5,5 artmıştır. Sonuç olarak, S. rebaudiana bitkisinin STF-4 çeşidinin ölçülen parametreler ışığında kuraklığa daha toleranslı olduğu ortaya konulmuştur.

Oxidation-Induced and Hydrothermal-Assisted Template-Free Synthesis of Mesoporous CeO2 for Adsorption of Acid Orange 7.

Hydrogen peroxide (H2O2), an accessible and eco-friendly oxidant, was employed for the template-free hydrothermal synthesis of mesoporous CeO2 based on a cerium carbonate precursor (Ce2(CO3)3•xH2O). Its microstructure and physicochemical properties were characterized by XRD, TEM and N2 sorption techniques. The formation of the CeO2 phase with a porous structure was strongly dependent on the presence of H2O2, while the values of the BET surface area, pore diameter and pore volume of CeO2 were generally related to the amount of H2O2 in the template-free hydrothermal synthesis. The BET surface area and pore volume of the mesoporous CeO2 synthesized hydrothermally at 180 °C with 10 mL H2O2 were 112.8 m2/g and 0.1436 cm3/g, respectively. The adsorption process had basically finished within 30 min, and the maximum adsorption efficiency within 30 min was 99.8% for the mesoporous CeO2 synthesized hydrothermally at 140 °C with 10 mL, when the initial AO7 concentration was 120 mg/L without pH preadjustment. The experimental data of AO7 adsorption were analyzed using the Langmuir and Freundlich isotherm modes. Moreover, the mesoporous CeO2 synthesized at 140 °C with 10 mL H2O2 was regenerated in successive adsorption–desorption cycles eight times without significant loss in adsorption capacity, suggesting that the as-synthesized mesoporous CeO2 in this work was suitable as an adsorbent for the efficient adsorption of AO7 dye from an aqueous solution.

In Situ Imaging of Endogenous Hydrogen Peroxide Efflux from Living Cells via Bipolar Gold Nanoelectrode Array and Electrochemiluminescence Technology.

The integration of a closed bipolar electrode (c-BPE) array and electrochemiluminescence (ECL) detection received a boost in applications in the detection of cell adhesion and disease-related biomarkers. This work proposed a gold nanorod array based c-BPE-ECL system to realize an in situ image of endogenous hydrogen peroxide (H2O2) efflux from living cells and parallel analysis of endogenous H2O2 released from multiple cells by converting electrochemical signals into optical signals. The gold nanorod array with high density was prepared by a repeating chronopotentiometry procedure with anodic aluminum oxide (AAO) membrane as a template. The c-BPE array was fabricated by assembling poly(dimethylsiloxane) (PDMS) chips on both sides of the gold nanorod array. When an appropriate driving potential is applied, H2O2 generated from living cells at the sensing pole was reduced on the gold nanorod, triggering the oxidation of the ECL reagent at the reporting pole, which allowed the detection of H2O2 released from living cells. Under phorbol myristate acetate (PMA) stimulation, H2O2 released from living HeLa, HepG2, MCF-7, and LO2 cells was determined to be 47, 32.4, 25.7, and 6.3 μM, respectively. This indicated that the amount of H2O2 released from PMA-stimulated cancer cells was significantly higher than that from the stimulated normal cells. This work presented a new approach for in situ imaging of H2O2 released from living cells and could also be used to detect other electrochemically active or non-electrochemically active molecules through simple cell surface modification, which may have potential applications in cell apoptosis study and disease diagnosis.

CuS NP-based nanocomposite with photothermal and augmented-photodynamic activity for magnetic resonance imaging-guided tumor synergistic therapy

Although many treatments have been developed for oncotherapy, the lack of effective imaging guidance in the therapeutic process is still an urgent problem to be solved. In this study, magnetic resonance contrast agent (Gd) chelated on CuS nanoparticles and glucose oxidase (GOx) were coloaded into mesoporous silica nanoparticles (MSNs) to form GOx-Gd-CuS@MSNs, in which the Gd provided magnetic resonance imaging (MRI) for therapeutic process monitor while GOx could catalyze the generation of H2O2 to enhance the photodynamic therapy (PDT). The in vitro results show that under near-infrared (NIR) laser irradiation (2 W·cm−2, 5 min), temperature rapidly increased by approximately 30 °C for the accumulation of heat. At the same time, GOx on GOx-Gd-CuS@MSNs effectively consumed glucose to produce a large amount of H2O2, which was used to augment PDT through producing highly toxic hydroxyl radicals (·OH) and singlet oxygen (1O2). The photothermal and augmented-photodynamic could induce apoptosis and death of tumor cells. More importantly, the study found that GOx-Gd-CuS@MSNs had MRI performance, which provided imaging guidance during the treatment process, and it can monitor the diffusion of water molecules in the tumor tissue during the treatment and microcirculation perfusion of capillary network. These results indicate that the nanomaterial produced significant synergistic therapeutic effects through photothermal and photodynamic forces, meanwhile showed excellent spatial resolution and deep tissue penetration in imaging.

The numerical simulation of nanosecond-pulsed discharge-assisted ignition in lean-burn natural gas HCCI engines

A plasma-assisted internal combustion engine model is established based on detailed plasma kinetics, combustion kinetics, and physical compression/expansion processes. The effects of nanosecond repetitively pulsed discharge (NRPD) on plasma-assisted ignition characteristics of mixtures under different fuel concentrations are studied under HCCI engine-relevant conditions. The coupled plasma and chemical kinetic model are validated with experiments. The comparison between NRPD and thermal ignition with a certain amount of input energy is carried out, and the results show that the former can ignite a mixture owing to the kinetic effect of nonequilibrium plasma, but the latter cannot ensure ignition. Path flux analysis shows that excited states and electrons react with fuel, providing O and H directly, increasing the possibility of ignition at a low temperature. The effect of NRPD on combustion performance under various equivalence ratios (φ) is investigated. It was found that in ICEs with NRPD, the ignition delay time under the lean-burn condition (φ = 0.5) is the shortest among three demonstrative cases. Even though the leaner mixture case with φ = 0.2 is more favorable for the production of O and OH during the discharge, after discharge, the heat release in case 2 with φ = 0.5 dramatically increases, resulting in the temperature exceeding that in the ultra-lean case. As the piston moves up, the higher amounts of CH3, HO2, and H2O2 as well as higher temperature for the lean-burn (φ = 0.5) case lead to the rapid increase of OH and O, which accelerates the consumption of methane and finally the earliest hot ignition near TDC. Finally, a series of parameter studies are performed to show the effects of E/N, current density, φ, and discharge timing on the ignition process. The results suggest that discharge parameters E/N and current density together with discharge timings and equivalence ratios can improve ignitability in internal combustion engines.

Photo-Fenton Degradation of Ciprofloxacin by Novel Graphene Quantum Dots/α-FeOOH Nanocomposites for the Production of Safe Drinking Water from Surface Water

In the current work, novel graphene quantum dots (GQDs)-doped goethite (α-FeOOH) nanocomposites (GQDs/α-FeOOH) were prepared by following a feasible hydrolysis method and applied for ciprofloxacin (CIP) removal. Results showed that the CIP degradation efficiency was significant (93.73%, 0.0566 min−1) in the GQDs/α-FeOOH + H2O2 + Vis system using much lower amounts of H2O2 (0.50 mM), which is 3.9 times the α-FeOOH + H2O2 + Vis system. It was found that •OH, O2•−, and 1O2 were mainly responsible for CIP degradation in the GQDs/α-FeOOH photo-Fenton system. GQDs/α-FeOOH demonstrated broad-spectrum UV–vis-IR responsiveness in the degradation of ciprofloxacin as a function of the doping of GQDs. Additionally, GQDs/α-FeOOH showed outstanding durability (recyclability up to 3 cycles with a lower iron leaking amount, 0.020 mg L−1), a broad range of application pH, and a pretty acceptable catalytic efficacy in a variety of surface water matrices. Overall, GQDs/α-FeOOH have been shown to be an effective photocatalyst for the remediation of emerging contaminants via the workable exploitation of solar energy.

Exogenous spermidine modulates polyamine metabolism and improves stress responsive mechanisms to protect tomato seedlings against salt stress

Salt stress negatively affects plant growth, development, and crop productivity causing serious economic loss to agricultural production. Here, we investigated the exogenous application of spermidine (Spd) on tomato seedlings grown under salt stress. Salt stress reduced plant growth, biomass accumulation and chlorophyll contents, thus negatively affecting photosynthesis. Alternatively, Spd application effectively reduced the salinity-induced adverse effects in tomato seedlings by activating the H2O2 mediated signaling involving the enhanced expression of RBOH1 and salt stress-responsive genes SlMYB102, SlHKT1, SlWRKY1 and SlDREB2, and improving detoxification through higher antioxidative activity and osmolyte (proline) accumulation under salt stress. It was further confirmed by significantly lower amount of H2O2, malondialdehyde and electrolyte leakage, and better ion homeostasis (Na+/K+ ratio) and photosynthetic performance of Spd-treated seedlings under salt stress. Furthermore, Spd application modulated endogenous polyamines and enhanced the biosynthesis of endogenous Spd and spermine from putrescine. Altogether, these results confirm the important role of Spd against salt stress and suggest that the increased endogenous Spd content in plants could regulate a number of stress-responsive mechanisms to protect tomato seedlings against salt stress. These results provide a good direction for further elucidation of the detailed interplay between polyamine metabolism and H2O2-mediated signaling, which would help to improve abiotic stress tolerance in plants.

Three new zinc(II) complexes: design, synthesis, characterization and catalytic performance

Three new Zn(II) complexes, [Zn2L2(OAc)2]2CH3OH (1), [ZnL(3-NA)2]·H2O (2) and [ZnL(2-NA)2] (3) were synthesized by the reaction of Zn(CH3COO)2·2H2O or Zn(ClO4)2·6H2O with 2-amino-N'-(pyridin-2-ylmethylene)benzohydrazide (HL), 3-nitrobenzoic acid (3-NA) or 2-nitrobenzoic acid (2-NA). The complexes were characterized by elemental analyses, single crystal X-ray diffraction, IR, UV-Vis and 1H NMR spectroscopy. The single crystal X-ray diffraction analyses revealed that the Zn ions in the complexes are five-coordinate in tetragonal pyramid configuration. The complexes and their starting materials Zn(CH3COO)2·2H2O and Zn(ClO4)2·6H2O were studied for their catalytic performance in the selective oxidation of cyclohexane (Cy) with aqueous H2O2 as oxidant. The conditions such as time, the amount of H2O2, solvent and HNO3 additive were optimized. The results showed that 3 has the best activity under mild conditions compared to the starting zinc materials and the referenced zinc complexes.

Electrochemical fabrication of polyaniline films deposited on graphene-loaded electrodes for •OH production and perfluorooctanoic acid degradation

The present study describes the coating of modified graphite felt (GF) with graphene (GE) and polyaniline (PANI). GF was doped with nitrogen atoms by a series of modification and electrolyticdeposition. Tests of different types of N content and cathodic catalytic oxidation performance confirmed that the graphite N introduction promoted the production of H2O2 in the 2e- process. Pyridine N catalyzed the H2O2 decomposition to produce •OH. The amount of H2O2 produced by GF, GF-GE, and GF-GE@PANI system was 11 mg L-1, 70 mg L-1, and 180 mg L-1, respectively. The doping of graphene increased H2O2 yield, and the electrolyticdeposition of PANI converted H2O2 to •OH rapidly. It was proved that the N atom provided by graphene was graphite N, which was the active catalytic site for the production of H2O2. The perfluorooctanoic acid (PFOA) removal at 180 min was 24.1% and 49.8% in the GF and GF-GE systems, respectively. The GF-GE@PANI system achieved 100% PFOA removal within 160 min. It was demonstrated that the enrichment of PANI with pyridine N provided many active sites for improving the conversion of H2O2 to •OH and in-situ degrading organic pollutants, offering an alternative for wastewater treatment.

Constitutive Defense Mechanisms Have a Major Role in the Resistance of Woodland Strawberry Leaves Against Botrytis cinerea.

The necrotrophic fungus Botrytis cinerea is a major threat to strawberry cultivation worldwide. By screening different Fragaria vesca genotypes for susceptibility to B. cinerea, we identified two genotypes with different resistance levels, a susceptible genotype F. vesca ssp. vesca Tenno 3 (T3) and a moderately resistant genotype F. vesca ssp. vesca Kreuzkogel 1 (K1). These two genotypes were used to identify the molecular basis for the increased resistance of K1 compared to T3. Fungal DNA quantification and microscopic observation of fungal growth in woodland strawberry leaves confirmed that the growth of B. cinerea was restricted during early stages of infection in K1 compared to T3. Gene expression analysis in both genotypes upon B. cinerea inoculation suggested that the restricted growth of B. cinerea was rather due to the constitutive resistance mechanisms of K1 instead of the induction of defense responses. Furthermore, we observed that the amount of total phenolics, total flavonoids, glucose, galactose, citric acid and ascorbic acid correlated positively with higher resistance, while H2O2 and sucrose correlated negatively. Therefore, we propose that K1 leaves are more resistant against B. cinerea compared to T3 leaves, prior to B. cinerea inoculation, due to a lower amount of innate H2O2, which is attributed to a higher level of antioxidants and antioxidant enzymes in K1. To conclude, this study provides important insights into the resistance mechanisms against B. cinerea, which highly depend on the innate antioxidative profile and specialized metabolites of woodland strawberry leaves.

Photocatalytic oxidative desulfurization of dibenzothiophene solution and real sample of fuel by using Mn-doped ZnO under visible irradiation

In this study, manganese was doped to ZnO by the hydrothermal method and calcined at different temperatures consist of: 3%MZ800, 6%MZ800, 9%MZ800, 9%MZ300, and 9%MZ400. The structural and optical properties of the samples were characterized using XRD, SEM, TEM, EDS, BET, DRS, and atomic spectroscopy analysis. Photocatalytic oxidative desulfurization of the solutions containing sulfur compounds was investigated by using the synthesized samples. 9%MZ400 showed the most desulfurization efficiency (95.99 ± 0.8%) for dibenzothiophene solution and (94.96 ± 1.3%) for AW 402 as a real sample of fuel in the presence of H2O2 and CH3COOH under visible-light irradiation (200 W tungsten). The leaching of Zn and Mn metal ions from photocatalyst isn’t occurred in this process. The optimum amounts of H2O2, CH3COOH and dosage of photocatalyst were obtained in desulfurization process. Also kinetics of desulfurization and stability of photocatalyst were investigated.

Strategies for anti-oxidative stress and anti-acid stress in bioleaching of LiCoO2 using an acidophilic microbial consortium.

High metal ion concentrations and low pH cause severely inhibit the activity of an acidophilic microbial consortium (AMC) in bioleaching. This work investigated the effects of exogenous spermine on biofilm formation and the bioleaching efficiency of LiCoO2 by AMC in 9K medium. After the addition of 1mM spermine, the activities of glutathione peroxidase and catalase increased, while the amount of H2O2, intracellular reactive oxygen species (ROS) and malondialdehyde in AMC decreased. These results indicated that the ability of AMC biofilm to resist oxidative stress introduced by 3.5g/L Li+ and 30.1g/L Co2+ was improved by spermine. The activity of glutamate decarboxylase was promoted to restore the intracellular pH buffering ability of AMC. Electrochemical measurements showed that the oxidation rate of pyrite was increased by exogenous spermine. As a result, high bioleaching efficiencies of 97.1% for Li+ and 96.1% for Co2+ from a 5.0% (wv-1) lithium cobalt oxide powder slurry were achieved. This work demonstrated that Tafel polarization can be used to monitor the AMC biofilm's ability of uptaking electrons from pyrite during bioleaching. The corrosion current density increased with 1mM spermine, indicating enhanced electron uptake by the biofilm from pyrite.

Copper-catalyzed direct hydroxylation of arenes to phenols with hydrogen peroxide

Direct hydroxylation of arenes to phenols with hydrogen peroxide as a green oxidant is an attractive approach. In the present study, we prepared several copper (II) complexes bearing tetra- (N4), tri- (N3) and pentadentate (N5) ligands, and the copperII-N4 complex could act as an efficient catalyst for hydroxylation of benzenes with H2O2 (up to 22.4% yield of phenols with 10.0 equiv. H2O2, and 38.0% yield of phenol with limited amount of H2O2) at room temperature. X-ray crystallographic analysis indicates that the CuII-N4 complex exhibits a square-pyramidal geometry and that two methyl groups connecting to the diamine are cis to each other. In comparison, copper(II) complexes supported by tri- (N3) and pentadentate (N5) ligands were also evaluated in the hydroxylation of benzene, demonstrating inferior performance.

Synthesis of Hydrogenated Natural Rubber Having Epoxide Groups Using Diimide.

Epoxidized natural rubber (ENR) with 50% mol of epoxide groups was synthesized using performic acid generated from the reaction of formic acid/hydrogen peroxide in latex form followed by hydrogenation using diimide generated from hydrazine (N2H4) and hydrogen peroxide (H2O2) with boric acid (H3BO3) as a catalyst. The resulting products (hydrogenated epoxidized natural rubber, HENR) were characterized by proton nuclear magnetic resonance spectroscopy (1H-NMR), gel testing, transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The effects of reaction parameters such as N2H4 amount, H2O2 amount, H3BO3 amount, gelatin amount, reaction time, and reaction temperature on the percentage of hydrogenation degree and gel content were investigated. The transmission electron micrographs of the particles confirmed a core/shell structure consisting of a highly unsaturated concentration region as the core encapsulated by a low carbon–carbon double bond concentration region as the shell, which indicated that the rubber particle seemed to be modified from the outer layer to the center of the rubber particle. Overall, the data showed that an increase in the amount of the individual chemicals, reaction time, and temperature increased the hydrogenation degree. However, a higher level of gelatin retarded an increase in the percentage of hydrogenation degree. As the hydrogenation degree increased, the gel content increased due to the ether linkage and the crosslinking reaction triggered through hydroxyl radicals. From DSC measurements, the glass transition temperatures of hydrogenated products increased above those of original rubbers. The thermal stability of hydrogenated products was improved, demonstrated by a decomposition temperature shift to a higher temperature than ENR, as shown by the results from the thermogravimetric analysis. Therefore, the hydrogenated ENR (HENR) exhibited good thermal stability, which could extend the applications of ENR in the automotive and oil industries.

CoN graphene encapsulated cobalt catalyst for H2O2 decomposition under acidic conditions

AbstractHydrogen peroxide (H2O2) has been listed as one of the 100 most important chemicals in the world. However, huge amount of residual H2O2 is hard to timely decomposed into O2 and H2O under acidic condition, easily resulting in explosion hazard. Here, we reported a core–shell structure catalyst, that is graphene with CoN structure encapsulated Co nanoparticles. CoN graphene shell serves as the active site for the H2O2 decomposition, and Co core further enhance this decomposition. Benefiting from it, the H2O2 decomposition were close to 100% after 6 cycles without pH adjustment, which increased 6 orders of magnitude compared with no catalyst. At the same time, the O2 generation reached 99.67% in 2 h with little metal leaching, and ·OH has been greatly inhibited to only 0.08%. This work can cleanly remove H2O2 with little deep oxidation and protect the process of H2O2 utilization to achieve a safer world.

Oblique Detonation Wave Control with O3 and H2O2 Sensitization in Hypersonic Flow

This numerical study investigates the effects of adding a small amount of ignition promoters for controlling the wedge-induced oblique shock wave (OSW) to oblique detonation wave (ODW) transition in a premixed hydrogen–air mixture at hypersonic speeds. The time-dependent two-dimensional compressible Euler equations for multiple thermally perfect species with a reactive source term are solved using adaptive mesh refinement and detailed chemical kinetics. The wedge with a fixed angle of 26° exhibits abrupt to smooth transitions for freestream Mach numbers 7–9 (speeds 2.8–3.2 km/s) at a pressure of 20 kPa and a temperature of 300 K. The small amount (1000 PPM by vol.) of H2O2 and O3 is found to be effective at significantly reducing the initiation length for the oblique detonation transition for all Mach numbers, which suggests a practical approach to increase the operating flight range for oblique detonation wave engine with a finite length wedge. At Mach number 8, the abrupt OSW to ODW transition turns towards a smooth transition with a small amount of H2O2 and O3 addition. Comparatively, O3 addition was found to be effective in reducing the ODW initiation length by promoting reactivity behind even a weaker oblique shock at low Mach number 7, for abrupt transition, while H2O2 addition was more effective than O3 at high Mach numbers 8 and 9, during a smooth transition. The maximum 73% and 80% reduction in initiation length of ODW was observed with 10,000 PPM H2O2 and O3 addition, respectively, during an abrupt OSW to ODW transition at Mach 7.

Soil Microorganisms and Seaweed Application With Supplementary Irrigation Improved Physiological Traits and Yield of Two Dryland Wheat Cultivars.

To evaluate the effect of useful soil microorganisms and organic compounds on physiological characteristics and yield of two wheat cultivars under supplementary irrigation conditions, a study was conducted in the Agriculture Research Farm of Kurdistan University during the two cropping seasons of 2017–2018 and 2018–2019. A split–split plot-based study on a randomized complete block design with four replicates was used as an experimental design. The main factor was irrigation at three levels, including control without irrigation, supplementary irrigation in the booting stage, and supplementary irrigation in the booting and flowering stages. Two wheat cultivars, namely, Sardari and Sirvan, as sub-factors and application of bio-fertilizers in eight levels, including the use of bio-fertilizers containing: Mycorrhiza, Seaweed extract, Nitrozist and Phosphozist, Mycorrhiza + Nitrozist and Phosphozist, Seaweed extract + Nitrozist and Phosphozist, Mycorrhiza + Seaweed extract, Mycorrhiza + Nitrozist and Phosphozist + Seaweed extract, and non-application of bio-fertilizers, were considered as sub-factors. The results of both seasons of the experiment showed that the application of bio-fertilizers compared to the control treatment at all irrigation levels increased root volume, leaf relative water content (RWC), membrane stability index (MSI), and photosynthetic pigment content. The highest amount of H2O2, proline, and soluble carbohydrates were obtained in wheat under dry land conditions, and supplementary irrigation, especially two-time irrigation, significantly reduced the values of these traits. Supplementary irrigation also increased grain yield, so that in the conditions of two-time irrigation compared to the non-irrigation treatment (dry land), in the first and second seasons, the grain yield increased by 79.51 and 78.69%, respectively. Application of bio-fertilizers (Mycorrhiza + Nitrozist and Phosphozist + Seaweed extract) in comparison with the non-application of these fertilizers, due to increased root volume, RWC, MSI, and content of photosynthetic pigments, increased the grain yield in the first and second seasons of the experiment by 8.04 and 6.96%, respectively. As a result, suitable microorganisms and seaweed can improve wheat resistance mechanisms to water deficit, which along with using supplementary irrigation that saves water consumption improves plant growth and yield in areas faced with water shortage.

Degradation of organic dye wastewater by H2O2-enhanced aluminum carbon micro-electrolysis.

In this research, the treatment of methylene blue (MB) dye wastewater by a novel system that combines H2O2 with an aluminum-carbon micro-electrolysis (ACE) was explored. The effects of the H2O2 amount, initial pH, aluminum to carbon ratio, total aluminum-carbon mass, dye concentration, and reaction temperature on degradation of MB were investigated. The findings revealed that under the following conditions: H2O2 34.0 mg/L, initial pH of 3.0, aluminum-to-carbon ratio of 2:1, total aluminum-carbon mass of 2.0 g/L, MB concentration of 20 mg/L, and 20 °C, the degradation rate of MB could reach 99.3% after 180 min, which is 18.4% more compared with ACE at the same conditions without H2O2. Through the quenching experiments, it was proved that the efficient free radicals produced during degradation are •OH and •O2-. Finally, a possible mechanism of H2O2 enhanced aluminum carbon micro-electrolysis (HP-ACE) for MB degradation was discussed.