Development economics

With the avadabihty of polymerization catalysts, extensive efforts were devoted to developing economical processes for manufacture of isoprene. Several synthetic routes have been commercialized. With natural mbber as an alternative, the ultimate value of the polymer was more or less dictated by that market. The first commercial use of isoprene in the United States started in 1940. It was used as a minor comonomer with isobutylene for the preparation of butyl mbber. Polyisoprene was commercialized extensively in the 1960s (6). In the 1990s isoprene is used almost exclusively as a monomer for polymerization (see ELASTOLffiRS,SYNTHETic-POLYisoPRENE). 

Composites fabricated with the smaller floating catalyst fiber are most likely to be used for applications where near-isotropic orientation is favored. Such isotropic properties would be acceptable in carbon/carbon composites for pistons, brake pads, and heat sink applications, and the low cost of fiber synthesis could permit these price-sensitive apphcations to be developed economically. A random orientation of fibers will give a balance of thermal properties in all axes, which can be important in brake and electronic heat sink applications. 

Likewise, fly ash from power plant combustors often contains small amounts of metals or their oxides, which require costly disposal in the ever-shrinking number of approved hazardous waste landfills. Thus, there are economic incentives to recover the metal values as well as to reduce the costs of ultimate disposal. Here, too, the metal content is low, and research is needed to develop economical separation processes. In principle, advances in this area could be translated into recovery of metal values from mine tailings. 

As with carboxylic acids obtained by palladium hydroxycarbonylation, their derivatives esters, amides, anhydrides and acyl halides are synthesized from alkenes, CO and HX (X = OR, NR2 etc.). The Pd-catalyzed methoxycarbonylation is one of the most studied reactions among this type of catalyzed carbonylations and has been reviewed and included in reports of homogeneous catalysis.625, 26 The methoxycarbonylation has been applied to many different substrates to obtain intermediates in organic syntheses as well as specific products. For instance, the reaction has been applied for methoxycarbonylation of alkynes666 Highly efficient homogeneous Pd cationic catalysts have been reported and the methoxycarbonylation of alkynes has been used to develop economically attractive and environmentally benign process for the production of methyl... 

Develop new less-energetic chemical reaction systems for product manufacture, including alternate catalytic and biological routes where appropriate Emphasize need to develop economically viable inherently safer systems at the research and development stages of new process development Develop new process equipment and strategies for product manufacture using lower inventories of reactive chemicals, error tolerant approaches, and process conditions further from limits of control where appropriate... 

Gunning, J. W. and Keyzer, M. A. (1995). Applied general equilibrium models for policy analysis. In Handbook of Development Economics, vol. 3A, pp. 2025-2107. 

For the inhabitants of the exclusion zone, situated in a forested region without well-developed economic and social infrastructures, it is of interest to estimate the relative contributions to internal exposure of forest food (berries and mushrooms) and conventional agricultural food (potatoes and milk). Some specialist studies have assumed that forest food represents only a small part of the diet of inhabitants of the exclusion zone, but we would suggest that in fact, it plays a major role. Typically, the consumption of forest food contributes 50% of the internal exposure dose, while for some critical population groups, it can exceed 80%. The definition of the spatial variation in pollution, the prevailing ecological conditions, and the diet should allow a scientifically-based prediction to be made of the internal exposure dose to the local population, and will help to identify the major risk factors within a certain time period following the Chernobyl catastrophe. 

The second part deals with applications of solvent extraction in industry, and begins with a general chapter (Chapter 7) that involves both equipment, flowsheet development, economic factors, and environmental aspects. Chapter 8 is concerned with fundamental engineering concepts for multistage extraction. Chapter 9 describes contactor design. It is followed by the industrial extraction of organic and biochemical compounds for purification and pharmaceutical uses (Chapter 10), recovery of metals for industrial production (Chapter 11), applications in the nuclear fuel cycle (Chapter 12), and recycling or waste treatment (Chapter 14). Analytical applications are briefly summarized in Chapter 13. The last chapters, Chapters 15 and 16, describe some newer developments in which the principle of solvent extraction has or may come into use, and theoretical developments. 

To date, use of this product has been limited for the purpose of developing economic and commercial data. Once this phase is completed, wider promotion should readily broaden the use of this material. 

The motivation for the vast majority of radiation chemical studies has been provided by considerations other than the desire to develop economically feasible processes. The approach has been fundamental, with the result that many data exist on systems having no possible application in the chemical process industry, while data on potential systems are lacking. Though extensive work on aqueous systems has been motivated by practical applications of these data to corrosion problems and biological systems, the approach has still been a fundamental one and the systems studied have been chosen so as to yield information... 

The cost for companies in terms of cash, possibly scarce water resources, ever tightening discharge limitations and perpetual liability for landfilled waste, requires that firms seek other solutions. The ideal solution is to develop economic point of use recycling and reuse systems. A technology that offers the potential for on-site recovery of a broad range of electronics and metal finishing applications is Advanced Reverse Osmosis (ARO). 

Optical fibers are the materials basis of the optical communication systems which in the last five years have essentially replaced the backbone long distance communication network in the U.S. and are now in submarine systems that connect the U.S. to both Europe and Asia. Developing economical fiber preparation techniques has depended on process physical chemical understanding. 

OECD. The OECD is a 29-member international group that discusses and develops economic and social policy in such areas as trade, public management, development assistance, and financial markets. 

The ultimate goal in most industrial research is to develop economically attractive processes or products. The technology of asymmetric hydrogenation of 2-arylacrylic acids is probably most useful for the production of naproxen and S-ibuprofen. Naproxen is currently one of the top ten prescription drugs in the world S-ibuprofen is the active isomer in the popular anti-inflammatory drug ibuprofen. Figures 5 and 6 summarize two commercially feasible processes for the manufacturing of these products. 

A different type of economic study, initiated in 1969, used an empirical formulation to develop economic estimates of vegetation damage (6). On the thesis that hydrocarbon emissions are related to oxidant production, hydrocarbon emission data were collected from over 100 metropolitan areas in the United States. Reductions in crop yields were empirically related to these emissions, and the monetary values were calculated. The reliability of this technique was based on known effects of oxidants on crop species and on the known relationship between hydrocarbons and oxidants. There are disadvantages to the method used, and the results suffer from lack of field verification. However, the technique has obvious advantages such as ease of use and uniformity of results. It might be a prototype from which more accurate estimates can be developed. Results from two years of development are found in annual reports (6, 7) and show between 100-125 million dollars lost annually in the United States. 

Tenneco develops economic process to recover ethylene from waste streams . Oil and Gas J, 76 (52) 199-200 (1978). 

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