Carbon history

History of Carbon. University of Kentucky Center for Applied Energy Research Web site. Available online. URL http //www. caer.uky.edu/carbon/history/carbonhistory.shtml. 

Growing fossil fuel use in the 20th century changed the carbon history of the earth. But deforestation also had an impact on carbon in the atmosphere. Forests serve as carbon sinks, producing oxygen while using carbon dioxide. 

The evolution of life curtailed the loss of water otherwise Earth could have lost the moisture which became a positive factor for the maintenance of life and may distinguish the Earth from other planets. Other important processes occurring during this early period which are particularly relevant to the Earth s carbon history include the removal of carbon from active circulation by weathering processes to produce additional carbonates in the oceans, as reflected in the following equations ... 

Shallow water carbonate (reefs carbonate muds) Reservoir quality governed by diagenetic processes and structural history (fracturing). Prolific production from karstified carbonates. High and early water production possible. Dual porosity systems in fractured carbonates. Dolomites may produce H S. 

Through an accident of history the simplest dicarboxylic acid carbonic acid HOCOH IS not even classified as an organic compound Because many minerals are carbonate... 

CARBON - CARBONAND ARTIFICIALGRAPHITE - STRUCTURE TERMINOLOGY AND HISTORY] (Vol 4)... 

Activated carbons contain chemisorbed oxygen in varying amounts unless special cate is taken to eliminate it. Desired adsorption properties often depend upon the amount and type of chemisorbed oxygen species on the surface. Therefore, the adsorption properties of an activated carbon adsorbent depend on its prior temperature and oxygen-exposure history. In contrast, molecular sieve 2eohtes and other oxide adsorbents are not affected by oxidi2ing or reducing conditions. 

Yohimbine (104), also from the bark of C.johimbe K Schum. and from the roots of R. serpentina (1. ) Benth. has a folk history (unsubstantiated) of use as an aphrodisiac. Its use has been confirmed experimentally as a local anesthetic, with occasional employment for rehef ia angiaa pectoris and arteriosclerosis, but is frequently contraindicated by its undesired renal effects. Yohimbine and some of its derivatives have been reported as hahuciaogenic (70). In addition, its pattern of pharmacological activities ia a variety of animal models is so broad that its general use is avoided. All ten carbon atoms of secologanin (102) as well as the entire skeleton of tryptamine (98, R = H) are clearly seen as iatact portions of this alkaloid. 

Although the use of simple diluents and adulterants almost certainly predates recorded history, the use of fillers to modify the properties of a composition can be traced as far back as eady Roman times, when artisans used ground marble in lime plaster, frescoes, and po22olanic mortar. The use of fillers in paper and paper coatings made its appearance in the mid-nineteenth century. Functional fillers, which introduce new properties into a composition rather than modify pre-existing properties, were commercially developed eady in the twentieth century when Goodrich added carbon black to mbber and Baekeland formulated phenol— formaldehyde plastics with wood dour. 

The combustible components of the gas are carbon monoxide and hydrogen, but combustion (heat) value varies because of dilution with carbon dioxide and with nitrogen. The gas has a low flame temperature unless the combustion air is strongly preheated. Its use has been limited essentially to steel (qv) mills, where it is produced as a by-product of blast furnaces. A common choice of equipment for the smaller gas producers is the WeUman-Galusha unit because of its long history of successful operation (21). 

The polymer is exposed to an extensive heat history in this process. Early work on transesterification technology was troubled by thermal—oxidative limitations of the polymer, especially in the presence of the catalyst. More recent work on catalyst systems, more reactive carbonates, and modified processes have improved the process to the point where color and decomposition can be suppressed. One of the key requirements for the transesterification process is the use of clean starting materials. Methods for purification of both BPA and diphenyl carbonate have been developed. 

A minimum of 10 to 35 parts carbon black to 100 parts of mbber is required to obtain a resistivity in the order of 10 Q-cm. At that loading the carbon black particles, which have an average radius of 10 nm, form grapelike aggregates that provide continuous paths for the electrical current. Special purpose mbbers containing even more carbon black have resistances as low as 1 Q-cm (129). The electrical resistivity of mbber with carbon black is sensitive to strain history, probably because of temporary dismptions of the continuity of the carbon black aggregates. 

Structure, Terminology, and History" under "Carbon (Carbon and Artificial Graphite)" ia ECT3rd ed., Vol. 4, pp. 556—560, byj. C. Long, Union Carbide Corp. 

Metastable growth of diamond takes place from gases rich in carbon and hydrogen at low pressures where diamond would appear to be thermodynamically unstable. The subject has a long history, beginning with work in the United States and Russia as early as 1962 (30—32) but not achieving widespread interest and acceptance until about 1986 after successful work in Japan. 

The production and price history for carbon disulfide in the United States appears in Table 4. Production peaked at 362,000 t/yrin 1969 and had... 

Figure 6.10 A perforated carbon steel pipe at a weld-backing ring. The gaping pit was caused by sulfate-reducing bacteria (see Case History 6.1).

Examination of the microstructure of the cavitated surface will commonly disclose evidence of deformation such as twins (Neumann hands) in carbon steel and general cold working in other metals (Case History 12.6). Damage from cavitation can be differentiated from attack by a strong mineral acid, which can produce a similar surface appearance, by observing the highly specific areas of attack characteristic of cavitation. Acid attack is typically general in its extent (Case History 12.6). 

Maintenance and production records, along with the used lean and rich glycol analyses, can be very helpful to the troubleshooter. A history of filter element, carbon, tower packing, and firetube changeouts can sometimes be very revealing. The frequency of pump repairs and chemical cleaning jobs is also beneficial. With this type of knowledge, the troubleshooter can quickly eliminate and prevent costly problems. 

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