Environmental consciousness

Narrow-bore columns are most useful for the analysis of polymers that are difficult to analyze in inexpensive solvents. However, if the appropriate equipment is available, good results can be obtained for a broad range of standard analyses. A comparison of an analysis of standards between an equivalent bank of conventional 7.8-mm and solvent efficient 4.6-mm columns is shown in Fig. 11.4. The columns used were Styragel HR 0.5, 1, 2, and 3 columns at 35°C with tetrahydrofuran (THF) as the solvent. The flow rate was 1 ml/min for the conventional columns (Fig. 11.4A) and 0.35 ml/min for the solvent-efficient 4.6-mm columns (Fig. 11.4B). If the correct equipment is available, the reduced solvent consumption of these solvent-efficient Styragel columns is of value to the environmentally conscious user. 

Not all decisions are made on the basis of economics alone. Consumers choose capital investments on the basis of efficiency, aesthetics and perceived benefits. An important environmental benefit of hybrid cars is the reduction in emissions. This is of particular relevance to an environmentally conscious consumer, and may shift the choice even though the benefit to the consumer is difficult to measure m dollars. 

J.A. Cano and G.J. McRae, Environmentally Conscious Chemical Process Design , Annu. Rev. Energy Environ., 1998, 23, 499. 

Imagine an automobile thatmns in silence and without polluting emissions. Such an automobile, long a dream of the environmentally conscious, has recently become a reality. The power source is a fuel cell, an electrochemical cell that uses a combustion reaction to produce electricity. Hydrocarbons such as natural gas and propane can be used in fuel cells, but the cleanest fuel is molecular hydrogen. 

As Table 21-1 suggests, molecular chlorine is a tremendously versatile industrial chemical. This element is a leading industrial chemical because of this versatility rather than any single application, although polymers account for about one third of its uses. In recent years, however, the industrial use of chlorine has come under strong attack from many environmentally conscious groups. One major reason is that dioxins, one class of by-products of chlorine reactions, have a very detrimental effect on biosystems. The controversy over industrial chlorine is described in our Chemistry and the Environment Box on page 936. 

Cano-Ruiz, l.A. McRae, G.J. (1998) Environmentally Conscious Chemical Process Design. Annual Review of Energy and the Environment, 23(1), 499-536. 

Three of five men, who lost consciousness within a few minutes of entering a partially drained underground liquid manure storage tank, died before reaching the hospital autopsy showed that two had massive liquid manure pulmonary aspiration, while the third had fulminant pulmonary edema without manure aspiration (Osbem and Crapo 1981). Markedly elevated heart-blood sulfide-ion levels indicated significant hydrogen sulfide exposure. Air samples analyzed about a week after the accident detected only 76 ppm of hydrogen sulfide, but the study authors noted that the environmental conditions were probably different (e g., warmer weather, less-concentrated manure). 

Finland Motives reflect a lifestyle choice environmental protection Health (products are pure and contain no residues) Conscience Price conscious consumer affected by unreliable quality... 

Lewis add catalysis has been and continues to be of great interest in organic synthesis.111 While various kinds of Lewis add-promoted reactions have been developed and many have been applied in industry, these reactions must generally be carried out under stridly anhydrous conditions. The presence of even a small amount of water stops the reaction because most conventional Lewis adds read immediately with water, rather than with the substrates, and decompose. This destrudive reaction has restrided the use of Lewis acids in organic synthesis. From a viewpoint of today s environmental consciousness, however, it is desirable to use water instead of organic solvents as a reaction solvent.1231... 

Due to many impressive advances in metal-catalyzed transformations, both asymmetric and non-asymmetric, several efforts have been directed towards designing total synthesis routes that very heavily depend on various catalytic methods. These total syntheses benefit from the economic efficiency and environmental consciousness that are two of the inherent attributes of catalytic reactions. The total synthesis of wodeshiol 133 by Corey, discussed above (Scheme 19) is one such example. Two additional catalysis-based enantioselective total syntheses are briefly discussed below. In both efforts, all centers of asymmetiy are attained by a catalytic enantioselective method, and the synthesis is completed through the use of several other catalytic reactions. 

E.K. Stefanakos, Y. Goswami, S.S. Srinivasan, and J. Wolan, Hydrogen Energy, Kutz, Myer (Hrsg.) Environmentally Conscious Alternative Energy Production, John Wiley Sons, 4lh volume, Chapter 7, 165 (September 2007). 

Research like this been has criticized for poor sampling, obsolete data, conflation of attitudes with behavior, and conflicting results. It has also been subject to the complaint that environmental consciousness has become so... 

Certainly, our conversations underlie the fact that that a direct relationship between socioeconomic status and environmental concern carmot be assumed. Michael and Tom, the least environmentally conscious residents of Kingberry Court, were the most highly educated (Michael) and had the highest income (Tom). 

The necessary inputs into the system are also by no means ecologically inert nor indisputably safe for human beings, especially children, wdldlife, and ambient ecosystems. Neither has the increasing environmental consciousness that has accompanied late twentieth century American sensibility resulted in a... 

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