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  2. Water splitting - Wikipedia

    en.wikipedia.org/wiki/Water_splitting

    In thermolysis, water molecules split into hydrogen and oxygen. For example, at 2,200 °C (2,470 K; 3,990 °F) about three percent of all H 2 O are dissociated into various combinations of hydrogen and oxygen atoms, mostly H, H 2, O, O 2, and OH. Other reaction products like H 2 O 2 or HO 2 remain minor. At the very high temperature of 3,000 ...

  3. Osmotic power - Wikipedia

    en.wikipedia.org/wiki/Osmotic_power

    Osmotic power, salinity gradient power or blue energy is the energy available from the difference in the salt concentration between seawater and river water.Two practical methods for this are reverse electrodialysis (RED) and pressure retarded osmosis (PRO).

  4. Photosystem II - Wikipedia

    en.wikipedia.org/wiki/Photosystem_II

    In 2011 the OEC of PSII was resolved to a level of 1.9Å revealing five oxygen atoms serving as oxo bridges linking the five metal atoms and four water molecules bound to the Mn 4 CaO 5 cluster; more than 1,300 water molecules were found in each photosystem II monomer, some forming extensive hydrogen-bonding networks that may serve as channels ...

  5. Chromism - Wikipedia

    en.wikipedia.org/wiki/Chromism

    In chemistry, chromism is a process that induces a change, often reversible, in the colors of compounds.In most cases, chromism is based on a change in the electron states of molecules, especially the π- or d-electron state, so this phenomenon is induced by various external stimuli which can alter the electron density of substances.

  6. Dioxygen in biological reactions - Wikipedia

    en.wikipedia.org/wiki/Dioxygen_in_biological...

    In blood, the heme group of hemoglobin binds oxygen when it is present, changing hemoglobin's color from bluish red to bright red. [7] [8] Vertebrate animals use hemoglobin in their blood to transport oxygen from their lungs to their tissues, but other animals use hemocyanin (molluscs and some arthropods) or hemerythrin (spiders and lobsters).

  7. Hill reaction - Wikipedia

    en.wikipedia.org/wiki/Hill_reaction

    Hill's finding was that the origin of oxygen in photosynthesis is water (H 2 O) not carbon dioxide (CO 2) as previously believed. Hill's observation of chloroplasts in dark conditions and in the absence of CO 2 , showed that the artificial electron acceptor was oxidized but not reduced, terminating the process, but without production of oxygen ...

  8. Ultra-high-purity steam for oxidation and annealing - Wikipedia

    en.wikipedia.org/wiki/Ultra-high-purity_steam...

    Oxygen: If oxygen makes up part of the process recipe during wet oxidation, it will reduce the water vapor partial pressure, slowing the overall growth rate. Because the oxidation rate of silicon with oxygen molecules to water molecules is almost ten times slower, variability in the oxygen to water vapor pressure can lead to process variability.

  9. Photooxygenation - Wikipedia

    en.wikipedia.org/wiki/Photooxygenation

    These 3 molecules form the basis of many synthetic photosensitizers. Sensitizers (denoted "Sens") are compounds, such as fluorescein dyes, methylene blue, and polycyclic aromatic hydrocarbons, which are able to absorb electromagnetic radiation (usually in the visible range of the spectrum) and eventually transfer that energy to molecular oxygen or the substrate of photooxygenation process.