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Energy and plastic

Energy and plastic Numerous studies have shown (1) plastics consume less energy to produce and fabricate products than other materials with glass being the major consumer of energy (2) their use as a product... [Pg.635]

In the present context, the data referring to daily variations in the ratio between energy and plastic metabolism are of special interest. It has been found that the processes of energy catabolism predominate in the daytime, while duplication and replication of DNA and protein synthesis dominate... [Pg.116]

It is probably the temperature rhythms that provoke the proper succession of basic metabolic processes throughout the year. Firstly, the energy and plastic reserves are to be laid down and, secondly, mobilized for generative production followed by, or even together with, somatic production. There is a direct relationship between the extent of the discrepancy between somatic and generative production and the degree to which a fish requires cold water. [Pg.239]

Matrix internal work 7m Matrix fracture Matrix surface energy and plastic flow... [Pg.440]

Dislocation theory as a portion of the subject of solid-state physics is somewhat beyond the scope of this book, but it is desirable to examine the subject briefly in terms of its implications in surface chemistry. Perhaps the most elementary type of defect is that of an extra or interstitial atom—Frenkel defect [110]—or a missing atom or vacancy—Schottky defect [111]. Such point defects play an important role in the treatment of diffusion and electrical conductivities in solids and the solubility of a salt in the host lattice of another or different valence type [112]. Point defects have a thermodynamic basis for their existence in terms of the energy and entropy of their formation, the situation is similar to the formation of isolated holes and erratic atoms on a surface. Dislocations, on the other hand, may be viewed as an organized concentration of point defects they are lattice defects and play an important role in the mechanism of the plastic deformation of solids. Lattice defects or dislocations are not thermodynamic in the sense of the point defects their formation is intimately connected with the mechanism of nucleation and crystal growth (see Section IX-4), and they constitute an important source of surface imperfection. [Pg.275]

Chemists make compounds and strive to understand their reactions. My own interest lies in the chemistry of the compounds of the elements carbon and hydrogen, called hydrocarbons. These make up petroleum oil and natural gas and thus are in many ways essential for everyday life. They generate energy and heat our houses, fuel our cars and airplanes and are raw materials for most manmade materials ranging from plastics to pharmaceuticals. Many of the chemical reactions essential to hydrocarbons are catalyzed by acids and proceed through positive ion intermediates, called carbocations. [Pg.182]

A range of plasticizer molecule models and a model for PVC have been generated and energy minimized to observe their most stable conformations. Such models highlight the free volume iacrease caused by the mobiHty of the plasticizer alkyl chains. More detailed models have also been produced to concentrate on the polar region of the plasticizer and its possible mode of interaction with the polymer. These show the expected repulsion between areas on the polymer and plasticizer of like charge as weU as attraction between the negative portions of the plasticizer and positive portions of the PVC. [Pg.124]

Vinyl compares favorably to other packaging materials. In 1992, a lifecycle assessment comparison of specific packages made from glass, paperboard, paper, and selected plastics concluded that vinyl was the material that has the lowest production energy and carbon dioxide emissions, as well as the lowest fossil fuel and raw material requirements of the plastics studied (169). Vinyl saves more than 34 million Btu per 1000 pounds manufactured compared to the highest energy-consuming plastic (170). [Pg.509]


See other pages where Energy and plastic is mentioned: [Pg.98]    [Pg.117]    [Pg.182]    [Pg.207]    [Pg.245]    [Pg.594]    [Pg.178]    [Pg.233]    [Pg.403]    [Pg.461]    [Pg.152]    [Pg.299]    [Pg.299]    [Pg.186]    [Pg.932]    [Pg.98]    [Pg.117]    [Pg.182]    [Pg.207]    [Pg.245]    [Pg.594]    [Pg.178]    [Pg.233]    [Pg.403]    [Pg.461]    [Pg.152]    [Pg.299]    [Pg.299]    [Pg.186]    [Pg.932]    [Pg.178]    [Pg.456]    [Pg.1436]    [Pg.206]    [Pg.87]    [Pg.124]    [Pg.523]    [Pg.151]    [Pg.281]    [Pg.148]    [Pg.544]    [Pg.102]    [Pg.505]    [Pg.203]    [Pg.300]    [Pg.291]    [Pg.572]    [Pg.332]    [Pg.395]    [Pg.416]    [Pg.257]    [Pg.1889]    [Pg.103]    [Pg.293]    [Pg.314]    [Pg.142]    [Pg.153]    [Pg.17]   
See also in sourсe #XX -- [ Pg.233 ]




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Plasticization energy

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