Carbon chemical aspect

Baillie, C.A., Castle, J.E., Watts, J.F. and Bader, M.G. (1991). Chemical aspects of interface adhesion between electrolytically oxidised carbon fibers and epoxy resins. In Proc. ICCMI8, Composites Design, Manufacture and Application. (S.W. Tsai and G.S. Springer, eds.), SAMPE Pub. Paper HE. 

One of the most desirable aspects of plastics and composites is the ability to make net-shaped parts. The same process that creates the material also creates the structure. The penalty for this advantage is that the process of curing a thermosetting plastic or composite part is irreversible. Any part that is not properly processed represents a loss of part, material and the money and time required to make that part, although larger parts are usually repaired if possible. Proper shape becomes a controlled property in addition to the bulk material properties, such as mechanical (stiffness or strength), physical (density, void content, etc.), chemical (degree of cure or carbonization, chemical resistance), electrical (resistivity, conductivity), or any combination of these. 

Carbon fibres are made by carbonizing or pyrolyzing polymer fibres. I came across the chemical aspects of this process in the book Principles of Polymerization by G. Odian in which the author describes how these fibres are made of polyacrylonitrile (PAN) a polymer which is represented in figure 14.4 (see also chapter 3). 

An extensive literature exists on the occurrence of early carbonate precipitates in marine sediments, where they are generally termed cements. Included in this literature are books devoted solely to carbonate cements (e.g., Bricker, 1971 Schneidermann and Harris, 1985) and numerous reviews (e.g., Milliman, 1974 Bathurst, 1974, 1975 Harris et al 1985). Many investigations have been largely descriptive in nature, focusing primarily on the distribution, mineralogy, and morphology of the cements. Here we will briefly summarize the major aspects of these observations, and we will concentrate on the chemical aspects of the formation of these precipitates. 

This book is divided into four major areas. The first three chapters deal with the more "basic" chemical aspects of carbonate minerals and their interactions with... 

Shvets D.I., Chochlova L.I., Kravchenko O.V. et al.The physico-chemical aspects of oil sorptiol by the carbon sorbents from water surface. Chemical and Technology Water, 24 (2002). pp.22-31 (Rus). 

Other contributions in this Treatise (Volumes 6-8) deal with the lithological and chemical aspects of evolution of specific types of (bio)-chemical sediments, such as cherts, phosphorites, hydrocarbons, and evaporites, and we will therefore concentrate on the most ubiquitous category, the carbonate rocks (see also Section 7.15.12). This carrier phase also contains the largest number of chemical and isotopic tracers. 

Section 3 treats with the chemical and physical processes during stabilization and carbonization. Although literature reports have been heavily consulted, and are duely referenced, the description of the whole process, and of the relative importance of physical and chemical aspects of it, in many instances represents the authors present opinion. 

It is probably fair to say that life reflects and depends on three chemical aspects (1) hybridization of carbon and oxygen (as well as nitrogen), (2) the facile way carbon atoms may bind to other carbon atoms, and (3) the unique ability of hydrogen to form H-bonds. The catenation and tetrahedral geometry of the carbon atoms are the fundamental features of all organic compounds in cells. However, the most abundant molecule in any living cell is water. 

Characterize the chemical aspects of photosmog. Write the cycles of chemical reactions in polluted urban air using carbon monoxide and methane as theexample species. 

From a more chemical aspect, in the initial stage of the thermal decomposition of coal (which can commence well below 200°C, or 390°F), the rate is usually slow and the process predominantly involves release of water, oxides of carbon, and hydrogen sulfide. As already noted, these products are considered to be the result of the thermal decomposition of thermally labile substituent groups that occur within the coal or from facile (but usually infrequent) condensation reactions (Figure 13.6). 

The physico-chemical aspects of the latter would, nevertheless, from an energetic point of view, have very much in common with those of a homogeneous solution of carbon bisulphide in carbon, if this would exist, since in both cases the energetic interaction would arise from exactly similar intermolecular forces. 

The main objective of the present review has been to collect the F-19 NMR data present in the literature between January 1979 and the end of June 1981. The format adopted follows that of the previous collection with the major portion of the information being presented in tabular form. The data have been compiled from the author s own records and from the literature abstracts of CA Selects Nuclear Magnetic Resonance (Chemical Aspects), Carbon and Heteroatom NMR, and Proton Magnetic Resonance. 

Carbamates comprise the esters and the salts of carbamic acids. This is a systematic classification from chemical aspects. Microbicides of this class of substances widely differ in terms of both efficacy and mechanisms of activity. The carbamic and dithiocarbamic acids, the basis of the carbamates, lack chemical stability they occur only intermediarily and disintegrate instantly to form carbon dioxide (CO2), carbon disulphide (CS2) and amine (see Fig. 31). 

The corrosivity of water to mild steel is related to certain chemical aspects of the water. The more important variables are dissolved oxygen, alkalinity, pH, chloride, sulfate, hydrogen sulfide, carbon dioxide, and ammonia. 

Although most NMR studies of carbon materials involve NMR experiments, many other nnclei can be used to probe local interactions and to extract information on structnral and chemical aspects of these materials. Thns, a multinuclear approach has been followed in numerous recent characterizations of different carbon materials by NMR. Besides the most obvious candidates H, O, and W N, whose corresponding chemical elements are routinely present in common carbon materials (excluding the elemental carbon forms), several other NMR-active... 

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