Economic problem

Ethanol can also be produced from cellulose (qv) or biomass such as wood (qv), com stover, and municipal soHd wastes (see Euels frombiomass Euels FROMWASTe). Each of these resources has inherent technical or economic problems. The Tennessee Valley Authority (TVA) is operating a 2 t/d pilot plant on converting cellulose to ethanol. 

One of the most exciting discoveries related to quinone/hydroquinone chemistry is thek synthesis by biosynthetic routes (12,13). Using bacterial enzymes to convert D-glucose [50-99-7] (7) to either 1,2- or l,4-ben2enediol allows the use of renewable raw material to replace traditional petrochemicals. The promise of reduced dependence on caustic solutions and the use of transition-metal catalysts for thek synthesis are attractive in spite of the scientific and economic problems still to be solved. 

By the mid-1990s capacity for polyethylene production was about 50 000 000 t.p.a, much greater than for any other type of plastics material. Of this capacity about 40% was for HDPE, 36% for LDPE and about 24% for LLDPE. Since then considerable extra capacity has been or is in the course of being built but at the time of writing financial and economic problems around the world make an accurate assessment of effective capacity both difficult and academic. It is, however, appeirent that the capacity data above is not reflected in consumption of the three main types of material where usage of LLDPE is now of the same order as the other two materials. Some 75% of the HDPE and LLDPE produced is used for film applications and about 60% of HDPE for injection and blow moulding. 

The economic problem is to identify the best capital investment from a set of possible alternatives. Selection is made on the basis of a systematic analysis of expected costs, and revenues if they differ, over time for each project alternative. 

Markets themselves are structured to be very responsive to whatever problems arise with resource supply. Depletion is an economic problem, and mar-... 

This chapter discusses the present status of microbial SCP production from agricultural wastes and describes some of the technical and economical problems related to the production processes that must be overcome for large-scale application to be possible. 

To maintain all boiler surfaces and other waterside surfaces in the HW and steam-system cycles in a structurally sound and clean condition, properly protected against the operational and economic problems associated with deposition, corrosion, fouling, and contamination... 

A network or graph consists of a set of points nodes) connected by lines edges or links). These links can be one-way (one can go from point A to B, but not vice versa) or two-way. When the edges are characterized by values, it is called a weighted graph. In the usual economic problems for which one applies networks, these values are cost, time, or distance. 

Some of the economic problems that confront the chemical industry and some practical problems of agriculture and society in general, resulting from the use of newer economic poisons, are discussed. Above all else, more facts are needed upon which to base both present procedures and future studies. 

The importance of economic problems in depression has been shown in a study of psychotherapy for depression conducted by two researchers in Chicago.55 They found that during the first two sessions of treatment, more than 85 per cent of the depressed patients spontaneously brought up issues relating to inadequate financial resources, difficult working conditions or unemployment. They also found that the patients... 

Some dinoflagellates of the genus Alexandrium produce neurotoxic compounds known as paralytic shellfish poisoning (PSP) toxins. Because these toxins can contaminate filter-feeding shellfish they may threaten public health and create economic problems for fisheries. PSP-toxins include at least a dozen saxitoxins, neosaxitoxins, and gonyautoxins (Scheme 1). 

Heinrich Buetefisch, one of the two greatest experts on fuel synthesis, had joined the SS for business reasons. With a few other industrialists he had also joined the Himmler s "circle of friends" to talk over Germany s economic problems with Himmler and Goering. 

The development of drugs for these diseases, intended for a limited number of patients, often requires considerable research, and is consequently costly. A particular approach of ethical, political and economical problems relevant for development and disposal of orphan drugs is also required. 

R D efforts are required in order to solve both technical and economic problems (for example, short life of some components, stress at high operating temperatures, high costs) and for better integration of all components in the plant. 

Present theories of the origin of acid rain indicate that we can limit acid rain by reducing sulfur dioxide emissions and moving to low-sulfur fuels but, only about 20% of the world s petroleum reserves are low in sulfur. Switching U.S. midwestern power plants to low-sulfur coal could cause economic problems since much of the coal from the Midwest and Appalachia has a high sulfur content. Most of the electric power generated in the Midwest uses high-sulfur coal and it would cost tens of billions of dollars to scrub the sulfur out of coal. 

The presence of aphids, Toxoptera graminum (Rondani) and Macrosiphum granarium (Kirby), on wheat during March and April has caused considerable alarm to wheat farmers in central Mexico. It has been found, however, that in the majority of cases the aphids do not represent a serious economic problem. Naturally occurring predators are able to reduce the aphid populations rapidly. For cases in which this natural biological control is not effective it has been found that benzene hexachloride (BHC) applied as a dust gives good control of these pests. 

Anodic corrosion in case of platinum metals mostly is insignificant or at least small for most anolyte compositions and conditions. But it may be an economic problem for industrial applications. Furthermore, as aforementioned, it can be the reason of cathode poisoning. The corrosion rate of gold, and especially of the less noble metals, is very dependent on the pH value of the anolyte. 

Fourth, the scope of the application must be bounded. There must be some specification of the functionality of the expert system and characteristics of the problems it is expected to solve. Trying to build an expert system to solve the world s economic problems is not a good application to choose. However, selecting a product mix from an oil refinery based on the current state of supply and demand in the world s energy markets might be a good application. 

In our program to provide consumers with safe, high quality products and respond to critical national and international needs to eliminate major impediments to expanding markets, a primary seafood utilization issue is the area of marine toxins that continue to present serious economic problems to the fishing industry and impact consumers. Ciguatera is one of the most treacherous and common forms of seafood poisoning in tropical waters. Also, sporadic outbreaks of PSP in shellfish from most of the major growing areas of North America... 

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