- Factors of polymer weathering
. Atmospheric Oxygen Photooxidation accounts for most polymer failure s that occur during outdoor exposure ... on the diffusion of oxygen through the polymer. Photooxidation is significantly reduced ... LDPE , polymethylmethacrylate PMMA and polyvinylchloride PVC show that photooxidation was higher ... on the front surface is transmitted to the back surface where it initiates photooxidation. Secondary ... stress. However, the contribution of ozonolysis reactions to the overall photooxidation process ... N 8, 2007, 487 500 ref Unsaturated alkyl and aromatic compound s may act as catalysts in the photooxidation ... more details
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- Oxygen-evolving complex
File Kok cycle.svg thumb The Kok cycle File Manganese cluster.svg thumb Possible arrangement of the metalloenzyme core of the OEC. The metal atoms are complexed by various amino acids The oxygen evolving complex , OEC also known as the water splitting complex, is a water oxidizing enzyme involved in the Oxygen evolution photooxidation of water during the light reactions of photosynthesis. Based on a widely accepted theory from 1970 by Kok, the complex can exist in 5 states S sub 0 sub to S sub 4 sub . Photons trapped by photosystem II move the system from state S sub 0 sub to S sub 4 sub . S sub 4 sub is unstable and reacts with water to produce free oxygen . Currently, the functional mechanism of the complex is not completely understood. Much of the known data have been collected from flash experiments, EPR, and X ray spectroscopy. ref Kok, B., B. Forbush, and M. McGloin. 1970. Cooperation of charges in photosynthetic O2 evolution. I. A linear four step mechanism. Photochem. Photobiol. 11 467 475. ref The OEC appears to have a metalloenzyme core containing both manganese and calcium , with the empirical formula for the inorganic core of Mn sub 4 sub Ca sub 1 sub O sub x sub Cl sub 1 2 sub HCO sub 3 sub sub y sub . Other characteristics of it have been reviewed see ref http mrw.interscience.wiley.com emrw 9780470862100 eic article ia128 current abstract Abstract Manganese The Oxygen Evolving Complex & Models1 Encyclopedia of Inorganic Chemistry Wiley InterScience Bot generated title ref It is suggested that the evolution of OEC is triggered by the presence of the manganese containing minerals rancieite and hollandite in the early oceans. The minerals were, it is presumed, assimilated by the early Cyanobacteria , which have incorporated them in the active center of the complex. References reflist Category Photosynthesis Category Light reactions Also see Life Ascending by Nick Lane, Profile Books 2009 pp 83 87, which outlines a possible route for the evolution of the ... more details
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- Diiodomethane
2003 2002JD002452.shtml New particle formation from photooxidation of diiodomethane Halomethanes Category ... more details
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- Sphingomonas
, M. Guiliano & J.C. Bertrand month May year 1999 title In vitro study of interaction between photooxidation ... more details
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- Salicylaldoxime
coauthors A San Pietro year 1966 title Inhibitory Effect Of Salicylaldoxime On Chloroplast Photooxidation ... more details
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- 1,2-rearrangement
Spectra of Purported Intermediates Formed during the Ceric Ammonium Nitrate Mediated Photooxidation ... more details
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- Photo-oxidation of polymers
Polymer chemistry Category Materials degradation de Photooxidation ... more details
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- Organic peroxide
ether peroxide . The photooxidation of diene s affords dialkyl peroxides . Many organometallic compounds ... more details
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- Stabilizers for polymers
neutralized by hydrochloric acid HCl that is released by photooxidation of PVC. The exception is the recently ... more details
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- Transition metal dioxygen complex
. S., Reactions of Organometallic Complexes with Singlet Oxygen. Photooxidation of Vaska s Complex ... more details
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- Grupo Modelo
&JournalCode PP title Riboflavin sensitized photooxidation of isohumulones and derivatives publisher ... more details
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- Tris(bipyridine)ruthenium(II) chloride
photoreduction or photooxidation, respectively. Current status of this field has been recently summarized ... more details
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- Isoprene
aerosols through photooxidation of isoprene journal Science issn 0036 8075 volume 303 issue 5661 ... more details
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- Photochromism
, photobleaching, photooxidation, and other side reactions. All photochromics suffer ... more details
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- Mark Purdey
. PMID 12389776 Does an ultra violet photooxidation of the manganese loaded copper depleted prion protein ... more details
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- Beer bottle
sensitized photooxidation of isohumulones and derivatives ref In some cases, such as Miller High ... more details
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- Perchlorate
oasys2.confex.com acs 231nm techprogram P945888.HTM Photooxidation of chloride to perchlorate in the presence ... more details
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- St John's wort
RH, Roberts JE title Photooxidation of lens alpha crystallin by hypericin active ingredient in St ... more details
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- Manganese
evolution photooxidation of water during the light reactions of photosynthesis and has a metalloenzyme ... more details
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