Polyester (1955 - present) started to replace acetate as a film support for many types of sheet film; however, due to its rigidity, it cannot be used as roll film. Polyester can also be identified as "safety" film. It is inherently more stable than both cellulose nitrate and cellulose acetate, because it is a synthetic polymer that is inert (chemically inactive). It shows exceptional chemical stability and physical performance.
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However, their reproduction by the very chemically inactive gas argon makes them unlikely to be a strictly chemical bonding to receptors in the usual sense of a chemical bond. An indirect physical effect – such as a change in membrane volume – would therefore be needed to affect the ligand-gated ion channels of nerve cells. Trudell et al. have suggested non-chemical binding due to the attractive van der Waals force between proteins and inert gases.
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These mechanisms include reducing heavy metal uptake, sequestering and storing heavy metals within the cell, and excretion. Heavy metal uptake can be reduced by sorption and metabolic inactivation at the cell wall and apoplast level. Ectomycorrhizal fungi also have the ability to bind considerable amounts of heavy metals. Once inside the cell, heavy metals can be immobilized in organo-metal complexes, made soluble, transformed into metallothioneins, involved in metal sequestration and/or stored in vacuoles in chemically inactive forms.
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Hydroponics refers to the technique of growing plants without soil. In hydroponic systems, the roots of plants are submerged in liquid solutions containing macronutrients, such as nitrogen, phosphorus, sulphur, potassium, calcium, and magnesium, as well as trace elements, including iron, chlorine, manganese, boron, zinc, copper, and molybdenum. Additionally, inert (chemically inactive) mediums such as gravel, sand, and sawdust are used as soil substitutes to provide support for the roots. The advantages of hydroponics include the ability to increase yield per area and reduce water usage.
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In general, Piecuch has been among the early and lead developers of multi-reference, response, extended, generalized, and externally corrected coupled-cluster methods, including approximate coupled-pair approaches for strongly correlated systems. His group and collaborators have also implemented linear scaling, local correlation coupled-cluster methods for large systems. The resulting multi-level local schemes that combine higher-level methods, such as CR- CC(2,3), to treat reactive parts of large molecular systems, with lower-order local or canonical methods, such as MP2 or CCSD, to describe chemically inactive regions are particularly valuable. Although the exponential wave function ansatz of coupled-cluster theory was originally proposed by nuclear physicists, it initially found limited applications in nuclear structure theory.
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Rinsing it out with alcohol removed the unusual sensitivity to green. He then tried adding small amounts of various aniline dyes to freshly prepared emulsions and found several dyes which added sensitivity to various parts of the spectrum, closely corresponding to wavelengths of light the dyes absorbed. Vogel was able to add sensitivity to green, yellow, orange and even red.Vogel, H: "On the sensitiveness of bromide of silver to the so-called chemically inactive colours", Chemical News, December 26, 1873:318-319, copying from The Photographic News, date and page not cited but apparently December 12, 1873, in turn translated from Vogel's own publication Photographische Mittheilungen, December, 1873 10(117):233-237.Vogel, H: "Photo-spectroscopic researches", The Photographic News, March 20, 1874:136-137, translated from Photographische Mittheilungen, February, 1874 10(119):279-283.
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As long as photographic materials were usefully sensitive only to blue-green, blue, violet and ultraviolet, three-color photography could never be practical. In 1873 German chemist Hermann Wilhelm Vogel discovered that the addition of small amounts of certain aniline dyes to a photographic emulsion could add sensitivity to colors which the dyes absorbed. He identified dyes which variously sensitized for all the previously ineffective colors except true red, to which only a marginal trace of sensitivity could be added.Vogel, H: "On the sensitiveness of bromide of silver to the so-called chemically inactive colours", Chemical News, December 26, 1873:318–319, copying from The Photographic News, date and page not cited but apparently December 12, 1873 (the latter not known to be available online as of August 6, 2010), in turn translated from Vogel's own publication Photographische Mittheilungen, December, 1873 10(117):233–237.
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