Enhanced As(III) oxidation and removal by combined use of zero valent iron and hydrogen peroxide in aerated waters at neutral pH values

2015 ◽  
Vol 297 ◽  
pp. 1-7 ◽  
Author(s):  
Ioannis A. Katsoyiannis ◽  
Andreas Voegelin ◽  
Anastasios I. Zouboulis ◽  
Stephan J. Hug
Keyword(s):  
Hydrogen Peroxide ◽  
Zero Valent Iron ◽  
Ph Values ◽  
Neutral Ph ◽  
Combined Use

scholarly journals A Silica-Supported Iron Oxide Catalyst Capable of Activating Hydrogen Peroxide at Neutral pH Values

2009 ◽  
Vol 43 (23) ◽  
pp. 8930-8935 ◽  
Author(s):  
Anh Le-Tuan Pham ◽  
Changha Lee ◽  
Fiona M. Doyle ◽  
David L. Sedlak
Keyword(s):  
Hydrogen Peroxide ◽  
Iron Oxide ◽  
Oxide Catalyst ◽  
Ph Values ◽  
Neutral Ph ◽  
Iron Oxide Catalyst ◽  
Supported Iron

scholarly journals Aferição do pH de diferentes agentes clareadores indicados para o clareamento intracoronário

2018 ◽  
Author(s):  
João Felipe Besegato ◽  
Gabriela Dos Santos Ribeiro Rocha ◽  
Marlene De Sousa Amorim ◽  
Fabio Martins Salomão ◽  
Daniel Poletto ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Statistical Analysis ◽  
Multiple Comparisons ◽  
The Other ◽  
Sodium Perborate ◽  
Distilled Water ◽  
Friedman Test ◽  
Time Intervals ◽  
Ph Values ◽  
Evaluation Time

Objective: to measure pH values of bleaching agents that are indicated to intracoronal bleaching technique in different time intervals. Methods: Each group (G) received five samples (n=5): G1 – distilled water (AD); G2 – hydrogen peroxide (H2O2) 30%; G3 – sodium perborate (PbS) + AD; G4 – PbS + H2O2 30%; G5 – sodium percarbonate (PcS) + AD; and G6 – PcS + H2O2 30%. pH values were stated using a digital pHmeter, in different time intervals: immediately after handling (T0), 24 hours (T1) and 168 hours after handling (T2). The results were submitted to statistical analysis through Kruskal-Wallis and Mann Whitney tests, in this order, allowing multiple comparisons among the groups. To verify the effect of time in each group, Friedman test was applied. Results: In the evaluation of the effect of time in each group, it was observed that G2 presented acid behavior, while the other groups exhibited values close to neutrality or alkaline. Conclusions: H2O2 30% was the only agent that showed acidic behavior in every evaluation time. Meanwhile, PcS + H2O had the highest pH values.

scholarly journals Effectiveness of the “Guanidez” disinfectant on the agents of bee infectious diseases in laboratory conditions

2019 ◽  
pp. 59-62
Author(s):  
O. S. Sirenko ◽  
O. V. Desyatnikova ◽  
V. B. Gurieva
Keyword(s):  
Hydrogen Peroxide ◽  
Infectious Diseases ◽  
Laboratory Tests ◽  
American Foulbrood ◽  
Combined Use ◽  
Microbiological Methods ◽  
Paenibacillus Alvei ◽  
Bactericidal Properties ◽  
European Foulbrood

The aim of the work is to study the effect of the disinfectant “Guanidez” on bee infectious diseases agents in vitro. Clinical-epizootological and microbiological methods have been used in the work. There were detected high disinfecting properties of the disinfectant “Guanidez” against pathogens of putrefactive diseases of bees. According to the results of the research, the technological regulation for the manufacturing of the preparation was developed: polyhexamethyleneguanidine hydrochloride at a concentration of at least 20.0%, hydrogen peroxide at a concentration of at least 35.0% and dimethylsulfoxide — 0.05 %. Disinfectant “Guanidez” exhibits pronounced bactericidal properties against the following cultures of microorganisms: Paenibacillus larvae (pathogen of American foulbrood), Melissococcus pluton, Paenibacillus alvei (pathogens of European foulbrood). The results of the “Guanidez” test indicate the effectiveness of the combined use of polyhexamethyleneguanidine hydrochloride, hydrogen peroxide and dimethylsulfoxide. The analysis of the results of laboratory tests of the “Guanidez” disinfectant for prophylactic and forced disinfection confirm its effectiveness and expediency of use for the control of putrefactive diseases

scholarly journals Inactivation of tyrosine aminotransferase in neutral homogenates and rat liver slices

1972 ◽  
Vol 129 (5) ◽  
pp. 1131-1138 ◽  
Author(s):  
F. Auricchio ◽  
L. Mollica ◽  
A. Liguori
Keyword(s):  
Amino Acid ◽  
Rat Liver ◽  
Acid Concentration ◽  
Tyrosine Aminotransferase ◽  
Amino Acid Concentration ◽  
Acidic Ph ◽  
Ph Values ◽  
Neutral Ph ◽  
Liver Slices

Inactivation of tyrosine aminotransferase induced in vivo by triamcinolone was studied in a homogenate incubated at neutral pH values. The integrity and the presence of subcellular particles together with a compartment of acidic pH are necessary for inactivation of tyrosine aminotransferase. It is suggested that tyrosine aminotransferase is inactivated inside lysosomes. The system responsible for inactivation of tyrosine aminotransferase was partially purified and identified with lysosomal cathepsins B and B1. Inactivation of tyrosine aminotransferase in liver slices is controlled by the amino acid concentration and strongly stimulated by cysteine. 3,3′,5-Tri-iodo-l-thyronine reversibly and strongly decreases the rate of inactivation of tyrosine aminotransferase. The effect is not due to an increased rate of tyrosine aminotransferase synthesis.

scholarly journals Combination of Bacillus licheniformis and Salinomycin: Effect on the Growth Performance and GIT Microbial Populations of Broiler Chickens

Animals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 889 ◽  
Author(s):  
Jacek Trela ◽  
Bartosz Kierończyk ◽  
Veerle Hautekiet ◽  
Damian Józefiak
Keyword(s):  
Growth Performance ◽  
Bacillus Licheniformis ◽  
Broiler Chickens ◽  
Body Weight Gain ◽  
Alpha Diversity ◽  
Feed Conversion ◽  
Beneficial Effects ◽  
Ph Values ◽  
Combined Use ◽  
Dietary Treatments

The aim of the study was to investigate the effect of Bacillus licheniformis and salinomycin supplementation in broiler diets as individual factors or in combination on the growth performance, GIT morphometry, and microbiota populations. Four hundred one-day-old Ross 308 chicks were randomly distributed to four dietary treatments (10 replicates, 10 birds each). The following treatments were applied: NC—no additives; NC + SAL—salinomycin addition (60 mg/kg diet), NC + PRO—B. licheniformis DSM 28710 preparation (1.6 × 109 CFU/kg; 500 mg/kg diet), and NC + SAL + PRO—combination of salinomycin and B. licheniformis. Probiotic administration resulted in improvement (p < 0.05) of the performance parameters, including body weight gain (1–10 d, and 11–22 d) and feed conversion ratio (11–22 d, 1–36 d). An interaction (p < 0.05) between experimental factors was observed in terms of lower pH values in the crop (tendency, p = 0.053) and ceca. Both factors lowered the alpha diversity and Enterobacteriaceae and promoted Bacillaceae communities in the jejunum (p < 0.05). Interactions were also observed in terms of reducing Clostridiaceae in the ceca. In conclusion, the combined use of B. licheniformis and salinomycin in broilers’ diets had beneficial effects.

Hydroxyl radical formation from bacteria-assisted Fenton chemistry at neutral pH under environmentally relevant conditions

2016 ◽  
Vol 13 (4) ◽  
pp. 757 ◽  
Author(s):  
Jarod N. Grossman ◽  
Tara F. Kahan
Keyword(s):  
Hydrogen Peroxide ◽  
Hydroxyl Radical ◽  
Natural Waters ◽  
Shewanella Oneidensis ◽  
Radical Formation ◽  
Production Rates ◽  
Fenton Chemistry ◽  
Iron Reducing Bacteria ◽  
Neutral Ph ◽  
Reducing Bacteria

Environmental contextReactions in natural waters such as lakes and streams are thought to be extremely slow in the absence of sunlight (e.g. at night). We demonstrate that in the presence of iron, hydrogen peroxide and certain bacteria (all of which are common in natural waters), certain reactions may occur surprisingly quickly. These findings will help us predict the fate of many compounds, including pollutants, in natural waters at night. AbstractDark Fenton chemistry is an important source of hydroxyl radicals (OH•) in natural waters in the absence of sunlight. Hydroxyl radical production by this process is very slow in many bodies of water, owing to slow reduction and low solubility of FeIII at neutral and near-neutral pH. We have investigated the effects of the iron-reducing bacteria Shewanella oneidensis (SO) on OH• production rates from Fenton chemistry at environmentally relevant hydrogen peroxide (H2O2) and iron concentrations at neutral pH. In the presence of 2.0 × 10–4M H2O2, OH• production rates increased from 1.3 × 10–10 to 2.0 × 10–10Ms–1 in the presence of 7.0 × 106cellsmL–1 SO when iron (at a concentration of 100μM) was in the form of FeII, and from 3.6 × 10–11 to 2.2 × 10–10Ms–1 when iron was in the form of FeIII. This represents rate increases of factors of 1.5 and 6 respectively. We measured OH• production rates at a range of H2O2 concentrations and SO cell densities. Production rates depended linearly on both variables. We also demonstrate that bacteria-assisted Fenton chemistry can result in rapid degradation of aromatic pollutants such as anthracene. Our results suggest that iron-reducing bacteria such as SO may be important contributors to radical formation in dark natural waters.

The Role of Electrochemical Conditions in Near-Neutral pH SCC Initiation Mechanism(s)

2010 ◽  
Author(s):  
Abdoulmajid Eslami ◽  
Mohammadhassan Marvasti ◽  
Weixing Chen ◽  
Reg Eadie ◽  
Richard Kania ◽  
...  
Keyword(s):  
Cathodic Protection ◽  
Pipeline Steel ◽  
Synergistic Effects ◽  
Co2 Concentration ◽  
Initiation Mechanism ◽  
Ph Values ◽  
Neutral Ph ◽  
Comprehensive Test ◽  
Disbonded Coating

In order to improve our understanding of near-neutral pH SCC initiation mechanism(s), a comprehensive test setup was used to study the electrochemical conditions beneath the disbonded coatings in cracking environments. In this setup the synergistic effects of cyclic loading, coating disbondment, and cathodic protection were considered. Our previous results showed that there can be a significant variation in the pH of the localized environment under the disbonded coating of pipeline steel. The pH inside the disbondment can change significantly from near-neutral to high pH values, strongly depending on the level of cathodic protection and CO2 concentration. Both of these variables affected the electrochemical conditions on the steel surface and therefore the initiation mechanisms. This work highlights the role of electrochemical conditions in near-neutral pH SCC initiation mechanisms.

Sign in / Sign up

Export Citation Format

Share Document