Industry Alternative Definitions

Chemical Process Industries versus the Chemicals and Allied Products Industry 

The task of fixing boundaries for the chemical industry has perplexed analysts for as long as attempts to collect statistics on the enterprise have been made. The working definition of the chemical industry adopted by the U.S. Bureau of the Census has changed periodically. During the past century the number of constituent industries in the chemicals and allied products group expanded along with the variety and number of chemical products manufactured in the United States. Older industries combined, new ones arose, and still others disappeared from the scene. 

From the nine industries included in the chemicals and allied products group at the turn of the century (general chemicals sulphuric, nitric, and mixed acids wood distillation paints and varnishes fertilizers explosives dyestuffs and extracts essential oils and bone, carbon, and lamp black), some 31 branches of chemical industry had evolved by the late 1950s. As 

For a detailed analysis of the comparability of Census categories pertaining to chemicals and allied products from 1929 to 1958, see II, Goldstein, 1959, 29 -31. 

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Alternative definitions of tray efficiency are sometimes used. Lockett (12) reviewed the pros and cons of several efficiency definitions. He cited the industry s experience that the more rigorous and theoretically correct a definition is, the more difficult it is to use, For instance, the Standart efficiencies are often considered the soundest fundamentally, but apparently have never been used for a design. For the design and operation engineer, the overall column (or section) efficiency is by far the most important. 

As industry is more concerned with the amount of woody tissue in a given volume of timber an alternative definition of density, the nominal density, is often preferred ... 

The CD-I (compact disk-interactive) is a low cost alternative to the CD-ROM for the entertainment industry. CD-I is a subset of the CD-ROM standard data format. It allows the digital storage of data, audio, and video information in a form that permits rapid interaction with a computer. CD-I is compatible to CD-ROM and to CD-AD 0 = 120 mm. The definition of the CD-I format is put down in the Green Book (Philips/Sony). 

This definition means that the depletion time of a resource is time dependent. The consumption rate of a resource may increase over time as a result of increased industrial production, or it may decrease if alternative resources are increasingly being used. Likewise, the regeneration rate may increase when more resources are recycled, and reserves may shrink after prolonged utilization or may expand when new natural deposits are found. In addition, more accurate data may become available, for example, on the extent of currently known reserves or on the natural formation rates of certain deposits. In any case, the depletion time x is variable, and it reflects the rate of resource depletion only in the present situation. 

There are some recent reviews on the topic of organic electrochemical processes in industry [13,64-69]. Most of these reviews list several dozens of electrochemical reactions that are reputed to have reached commercial status, at least for a period of time. Many cases are not definitely confirmed some have been operated commercially for some years but are believed to be obsolete today (see Table 1). D. Degner has compiled the relevant patent literature for industrially important reactions that have been studied between the early 1970s and the late 1080s [70]. Table 1 presents many of these examples, but its message often is only These are electrochemical reactions that have or had the opportunity to achieve costs equal to those of alternatives. 

The diversification of energy sources tailored to the requirements and resources of each country using nature s renewable resources such as the sun (photovoltaics), wind power, geothermal energy and biomass is a definite requirement. If solar cells are chosen to provide an alternative to fossil fuels, significant research work is needed (i) to develop new routes for the production of crystalline silicon, (ii) in the development of amorphous silicon hybrid materials that could result in enhanced efficiencies, (iii) for further development of thin-layer technology, (iv) in concerted efforts for cheaper and more stable dyes, (v) in improving the efficiency of the dye-sensitized cells and (vi) in process development to deliver enhanced device performances, ensure sustainability and reduce production costs on an industrial scale. 

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