• Hydrogen peroxide (H2O2) is formed by interaction of metabolism and oxygen. (plymouth.ac.uk)
  • H2O2 was found to be the most important oxidant for aqueous sulfate production 68% of the time. (cdc.gov)
  • These effects were found to be only of minor importance, however, as H2O2 was the dominant S(IV) oxidant most of the time. (cdc.gov)
  • The most commonly used chemicals for tooth bleaching usually contain some form of hydrogen peroxide (H2O2) at different concentrations. (bvsalud.org)
  • H2O2 is an oxidant agent that, with the aid of some chemical or physical activators (i.e., enzymes, light or heat), dissociates in perhydroxyl and oxygen radicals. (bvsalud.org)
  • The accumulation of vitamin C preferentially in cancer tissues has raised concerns that vitamin C may provide tumours with anti-oxidant protection from chemotherapeutic agents. (canceractive.com)
  • This novel selective oxidation reaction takes place under mild conditions (room temperature, alcoholic solvents) with hydrogen peroxide as benign terminal oxidant. (chemistryviews.org)
  • The use of urea-hydrogen peroxide as terminal oxidant in the presence of diphenyl diselenide as catalyst enables a highly selective catalytic oxidation of sulfides into the corresponding sulfoxides. (organic-chemistry.org)
  • Urea-hydrogen peroxide is a non-toxic, odorless crystalline solid. (organic-chemistry.org)
  • Urea-hydrogen peroxide in the presence of a catalytic amount of magnesium bromide efficiently oxidizes primary and secondary benzylic alcohols into the corresponding aromatic aldehydes and ketones. (organic-chemistry.org)
  • Methyltrioxorhenium (MTO) catalyzes an oxidation of methyl trimethylsilyl ketene acetals with urea hydrogen peroxide to afford α-hydroxy and α-siloxy esters. (organic-chemistry.org)
  • Eco-friendly laboratory procedures allow the oxidative iodination of various activated and deactivated arenes with molecular iodine, in the presence of UHP (percarbamide), a stable, strongly H-bonded, solid urea-hydrogen peroxide adduct as the oxidant. (organic-chemistry.org)
  • Urea-hydrogen peroxide adduct (UHP) is stable, inexpensive and an easily handled reagent. (organic-chemistry.org)
  • The use of urea-hydrogen peroxide and phthalic anhydride in ethyl acetate enables a metal-free, environmentally benign oxidation of substituted sulfides to their corresponding sulfones without observation of the possible sulfoxide oxidation product. (organic-chemistry.org)
  • Oxidation of hydrogen sulphide is also a function of temperature, pH and ionic strength. (canada.ca)
  • The rate of hydrogen sulphide oxidation was found to increase with increasing temperature and pH up to pH 8. (canada.ca)
  • In this work, a series of Brønsted acidic ionic liquids having different protonated amide-based cations were synthesized and investigated as solvents and catalysts in the oxidation desulfurization of diesel fuel, with hydrogen peroxide as oxidant. (confex.com)
  • Her role in the award-winning project was developing the state-of-the-art catalyst used for the reaction that produces hydrogen peroxide, which she has been working toward for "about seven years," even pre-dating her arrival at UCalgary. (ucalgary.ca)
  • At the time, I was researching to find a suitable catalyst to product hydrogen peroxide. (ucalgary.ca)
  • We would talk about our work, and I had the idea that the catalyst should possess special atomic arrangements to enhance the hydrogen peroxide selectivity. (ucalgary.ca)
  • The first epoxidation method was catalytic epoxidation in ILs where product separation was possible using a heterepoly acid based catalyst and hydrogen peroxide as oxidant. (dtu.dk)
  • This superoxide anion is then converted to relatively bactericidal reactive oxidants, such as hydroxyl radical (OH - ), hydrogen peroxide (H 2 O 2 ), peroxynitrite anion (ONOO - ), and oxyhalides (HOX - , in which the X moiety is most commonly chlorine). (medscape.com)
  • Overall, ozone was found to be the most important aqueous S(IV) oxidant in 21% of the sampling periods. (cdc.gov)
  • [17] Exposure to ultraviolet (UV) radiation can cause direct photooxidation and decompose peroxides and carbonyl molecules. (wikipedia.org)
  • The idea that pro-oxidant molecules are always destructive is "oversimplified to the point of probably being wrong," says Toren Finkel, chief of the center for molecular medicine at the National Heart, Lung, and Blood Institute in Bethesda, Maryland. (bigthink.com)
  • The term "fuel crossover" refers to the unintended movement of fuel (hydrogen molecules, not hydrogen ions), from the anode to the cathode, across the electrolyte. (openwetware.org)
  • They react with ROS, neutralizing the pro-oxidants before they can damage important cellular machinery. (bigthink.com)
  • This review focuses on emerging topics encompassing the functional involvement of aquaporin channel proteins (AQPs) and membrane transport systems, also allowing permeation of NO and hydrogen peroxide, a major ROS, in oxidative stress physiology and pathophysiology. (hindawi.com)
  • This review focuses on an emerging topic, the functional involvement of AQPs in ROS membrane transport, with specific regard to the movement of hydrogen peroxide and NO into and out of cells, in both health and oxidative stress-induced diseases. (hindawi.com)
  • High concentrations of hydrogen sulfide gas are both flammable and poisonous. (purewatergazette.net)
  • Footnote 15 Natural waters containing elevated concentrations of hydrogen sulphide are used for therapeutic baths and have been consumed for medical purposes. (canada.ca)
  • Hydrogen peroxide is a "weak acidic, clear, colorless fluid, easily mixed with water in all proportions. (purewatergazette.net)
  • Footnote 3 Footnote 4 In polluted waters, therefore, where the pH can be neutral or acidic, the potential for hydrogen sulphide formation is increased. (canada.ca)
  • We produce native antioxidants, such as the molecule glutathione, to counteract this pro-oxidant threat. (bigthink.com)
  • Consequently, various methods have been developed in order to measure the total oxidants (such as TOC and TOS assays) or antioxidants (such as FRAP and ORAC assays), separately. (hindawi.com)
  • In this context, PAB assay is developed to measure the balance of oxidants and antioxidants simultaneously in one experiment and give a redox index [ 7 , 9 , 10 ]. (hindawi.com)
  • Our cells have therefore developed powerful defence mechanisms to get rid of these oxidants, which are formed in our normal metabolism. (salaha.in)
  • It is also one of the oxidants formed in our metabolism that is harmful at higher concentrations. (salaha.in)
  • Hydrogen peroxide is a chemical used for hair and tooth whitening, among other things. (salaha.in)
  • Many chemical suppliers have seven-percent peroxide already available or can make it up in many cases. (purewatergazette.net)
  • Be sure to determine what peroxide strength is being used and adjust for the calculations when sizing and setting chemical feeders 1 . (purewatergazette.net)
  • Footnote 14 Hydrogen sulphide and other soluble sulphides are utilized in pigment and dye manufacturing, tanning and pulp and chemical processing. (canada.ca)
  • Using a device called an electrolyzer, this new method allows hydrogen peroxide, an environmentally friendly chemical for treating water, to be made on-site and on demand. (ucalgary.ca)
  • Hydrogen peroxide is a very unique chemical in the world," she says. (ucalgary.ca)
  • Hydrogen peroxide also can be used as fuel because it has the same amount as hydrogen in its chemical structure as fuel hydrogen. (ucalgary.ca)
  • Hydrogen peroxide, Siahrostami explains, is also a strong chemical oxidant, meaning that it can boost other reactions, such as those requiring an oxidizing agent. (ucalgary.ca)
  • The work represents just one of many steps that Beller's group are taking "en route" towards more sustainable industrial chemical processes. (chemistryviews.org)
  • An MFC is a device that converts chemical energy from fuel into electrical energy, using a microfluidic system to transport the fuel and oxidant to the electrodes instead of conventional polymeric membranes. (openwetware.org)
  • The importance of ozone as a S(IV) oxidant increased substantially as cloud pH climbed above pH 5 to 5.3. (cdc.gov)
  • Another challenge is precise controlling of the flow of fuel and oxidants to avoid crossover, which can be difficult in a small-scale system. (openwetware.org)
  • Hydrogen peroxide also occurs naturally. (purewatergazette.net)
  • Hydrogen sulphide, which exists as a colourless gas under normal conditions, also occurs naturally in coal, natural gas, oil, volcanic gases and sulphur springs and lakes. (canada.ca)
  • HPNow has locations in more than 15 countries around the world, including its own solar-powered emission-free hydrogen peroxide production plant in Spain. (ucalgary.ca)
  • But a study from the Chalmers University of Technology, Sweden, has now shown that low levels of the oxidant hydrogen peroxide can stimulate an enzyme that helps slow down the ageing of yeast cells. (salaha.in)
  • Now, the new research from the Chalmers University of Technology shows that the well-known oxidant hydrogen peroxide can actually slow down the ageing of yeast cells. (salaha.in)
  • But now we have shown that Tsa1 actually requires a certain amount of hydrogen peroxide to be triggered in order to participate in the process of slowing down the ageing of yeast cells. (salaha.in)
  • Surprisingly, the study shows that Tsa1 does not affect the levels of hydrogen peroxide in aged yeast cells. (salaha.in)
  • On the contrary, Tsa1 uses small amounts of hydrogen peroxide to reduce the activity of a central signalling pathway when cells are getting fewer calories. (salaha.in)
  • Her research interests include the advanced materials processing of ideal electrode materials for electrochemical energy storage system applications such as supercapacitor, water splitting process, direct methanol fuel cells, and hydrogen generation. (rsc.org)
  • Oxidants may be a primordial messenger of stress in our cells, and a little bit of stress, it turns out, may be good for us. (bigthink.com)
  • High dose vitamin C involves intravenous injections of vitamin C of up to 85 gm (depending upon body weight), every 5 days, for 8 rounds to increase 'Hydrogen Peroxide' levels in cells. (canceractive.com)
  • Tumour cells have 10-100 times less catalase than normal cells, and are therefore more sensitive than normal to hydrogen peroxide. (canceractive.com)
  • To obtain vitamin C at pro-oxidant levels, at which it destroys cancer cells, is only achievable by intravenous infusion. (canceractive.com)
  • Microchannels or microchannel networks, which feature a substantially higher surface-area-to-volume ratio than conventional fuel cells, are used to feed the fuel and oxidant to the electrodes that ensure their quick and efficient transport to the electrode surface, increasing power production and efficiency. (openwetware.org)
  • At this point we have to read carefully, because this is the insidious part: "In a study conducted in the laboratory, they discovered human lung airway cells exposed to either cigarette smoke or hydrogen peroxide - one of several oxidants found in cigarettes - both developed changes indicative of cancer. (forces.org)
  • Airway cells not exposed to either cigarette smoke or hydrogen peroxide did not undergo the changes. (forces.org)
  • Genetically-encoded fluorescent sensors with high specificity for peroxide can overcome some of these problems. (plymouth.ac.uk)
  • Leather gloves, for example, are not recommended for handling high concentrations of peroxide. (purewatergazette.net)
  • These factors were supposed to contribute to high desulfurization performance by improving the formation of peroxides, and a corresponding mechanism was put forward. (confex.com)
  • While it is a potentially damaging oxidant, it also has roles in pathogen defence, signalling and development. (plymouth.ac.uk)
  • Many dealers are purchasing 35 percent technical grade peroxide for diluting and using four gallons of water to one gallon of 35 percent peroxide. (purewatergazette.net)
  • Hydrogen sulphide and sulphides of the alkali and alkaline earth metals are soluble in water. (canada.ca)
  • An assistant professor in the Department of Chemistry , Siahrostami and a team of international researchers have made the scientific and technical breakthroughs that allow hydrogen peroxide to be produced anywhere, on demand, using only water, electricity, and air. (ucalgary.ca)
  • The new electrolyzer technology can be placed into the water at treatment plants, delivering hydrogen peroxide on-site while also saving energy. (ucalgary.ca)
  • The electrons flow through an external circuit to the cathode, where they combine with the protons and the oxidant to form water. (openwetware.org)
  • Larger amounts of oxidants can cause serious damage to DNA, cell membranes and proteins for example. (salaha.in)
  • The fact that researchers have now come to a step closer to understanding the mechanisms behind how oxidants can actually slow down the ageing process could lead to new studies, for example looking for peroxiredoxin-stimulating drugs, or testing whether age-related diseases can be slowed by other drugs that enhance the positive effects of oxidants in the body. (salaha.in)
  • Footnote 20 Levels of undissociated hydrogen sulphide were undetectable in Florida Bay, Footnote 21 and a maximum concentration of 14 µg/L has been recorded for the Arabian Sea. (canada.ca)
  • 5. This is a powerful oxidant. (mis-asia.com)
  • Hydrogen peroxide (H 2 O 2 ) is another method that can be used and has gained a lot of popularity because it is easier to handle, is a more powerful oxidizer and, in most cases, doesn't require a contact tank. (purewatergazette.net)
  • Oxidant cream specifically created in order to obtain one lightening tone or to cover white hair with Mask and for a medium decolouring action with L'Art Decolour system. (studiodesigncenter.gr)
  • As with any other oxidant, safety still needs to be considered when handling this product. (purewatergazette.net)
  • These oxidants are formed in the mitochondria, the 'powerhouse' of a cell, and the process, called mitohormesis, can be observed in many organisms, from yeast to mice. (salaha.in)
  • Canadian production of hydrogen sulphide by manufacturers of pigments and dye colours amounted to 10.7 tonnes in 1974. (canada.ca)
  • I think what a lot of people don't realize is that the antioxidant and pro-oxidant balance is really delicate. (scienceagogo.com)
  • There are safety videos available from many of the suppliers and manufacturers of hydrogen peroxide. (purewatergazette.net)
  • Manufacturers of industrial chemicals produced 2461 tonnes of hydrogen sulphide during the same period. (canada.ca)
  • Footnote 16 Canadian consumption of hydrogen sulphide by manufacturers of industrial chemicals was 3153 tonnes in 1980. (canada.ca)
  • The proportion of undissociated hydrogen sulphide has been shown to decrease with increasing salinity for a given temperature and pH. (canada.ca)