Imagining studies

So the animals used in the toxicity test, both treated and control animals, are subjected to extremely thorough medical monitoring, even to the point of sacrificing their lives so that the toxicologist can learn in minutest detail whether any of their tissues have been damaged. Obviously, there is no way such thorough information could ever be collected from any imaginable study of humans exposed to chemical substances. 

Systematic study of photochemistry is at a crossroad at this time. The past ten years have been a period of especially interesting and vigorous development. Understanding of some kinds of basic principles has been considerably clarified and the breadth of available information has increased enormously because of the imaginative study of large, complex molecules. However, I believe that the field needs clarification of concepts concerning the fundamental processes in which electronic excitation energy is used to make and break chemical bonds. 

These highly imaginative studies may duplicate some of the changes that occur during the liquid-to-gas transition at birth, and thus may explain some of the complications encountered and possibly provide new insights for the therapy of surfactant deficiency in idiopathic respiratory disease of the newborn. 

NLH shows abundant reactive lymphoid nodules and intervening reactive lymphoid cells, so it is microscopically similar to some cases of LIP. The difference is that this disease occurs in chest imagining studies as one or several localized lesions, rather than as a diffuse bilateral interstitial infiltrate. 

The physical chemist is very interested in kinetics—in the mechanisms of chemical reactions, the rates of adsorption, dissolution or evaporation, and generally, in time as a variable. As may be imagined, there is a wide spectrum of rate phenomena and in the sophistication achieved in dealing wifli them. In some cases changes in area or in amounts of phases are involved, as in rates of evaporation, condensation, dissolution, precipitation, flocculation, and adsorption and desorption. In other cases surface composition is changing as with reaction in monolayers. The field of catalysis is focused largely on the study of surface reaction mechanisms. Thus, throughout this book, the kinetic aspects of interfacial phenomena are discussed in concert with the associated thermodynamic properties. 

HAZOP (Knowlton, 1989 Lees, 1980 CPQRA, 1989, pp. 419-422). HAZOP stands for hazard and operability studies. This is a set of formal hazard identification and elimination procedures designed to identify hazards to people, process plants, and the environment. The techniques aim to stimulate in a systematic way the imagination of designers and people who operate plants or eqmpment so they can identify potenti hazards. In effect, HAZOP studies make the assumption that a hazard or operating problem can arise when there is a deviation from the design or operating intention. Corrective actions can then be made before a real accident occurs. 

When considering release scenarios, the most hazardous unit in a plant should be chosen, based on inventoiy and process conditions. The idea is to imagine the release of material in the fastest way that is reasonably possible. The worst realistic scenario should be considered. This can be based on the outcome of a review, from a HAZOP study or a hazard analysis. The time a scenario will take is almost always considered to be continuous, because after a few minutes a stable dispersion distance exists. Making the time longer will not necessarily change the hazard distance. 

The incidents listed earlier in this chapter and many others could have been foreseen if the design had been subjected to a hazard and operability study (hazop). This technique allows people to let their imaginations go free and think of all possible ways in which hazards or operating problems might arise. But to reduce the chance that something is missed. 

Graft reactions on cellulosics are well studied and are well known to incorporate desired properties in polymers [61,72,73,76,77,99-102], but commercialization of the processes on cellulosics are not increasing. (Table 4 gives a summary of the techniques of grafting.) A fresh imaginative approach is required to solve this problem. 

One very useful application arises when the desired reaction is difficult to measure kinetically. For example, imagine that the reaction of A) and B, the process of interest, does not produce an appreciable instrument signal under the concentration conditions the experiment requires. The reaction of A2 and B, however, can be coupled to it. If this second reaction is well characterized, with a known rate constant, and if P2 is easily detected, one can then study the concurrent reactions of A] and A2 with B. These will then provide the value of the otherw ise unknown k. Since B is limiting, [Pi ] = [B]o [P2]. thereby providing a value for the otherwise unmeasured concentration. With A2 known, the rate constant is... 

The latter part of the 20th century has seen remarkable advances in science and technology. Accomplishments in biochemistry and medicine, computer technology, and telecommunications have benefited nearly everyone on Earth to one degree or another. Along with these advances that have improved our quality of life, scientific research into the study of the Earth has revealed a planetary system that is more complex and dynamic than anyone would have imagined even 50 years ago. The Earth and the environment have become one of society s greatest concerns, perhaps as the result of these discoveries combined with the quick dissemination of information that is now possible with modem telecommunications. 

Scientists do not believe that life is arising from non-life on Earth today, but, if life originated on Earth, as it apparently did, it must have developed from non-living materials. Current scientific views of when and how life might have originated and evolved are based upon imaginative chemical experiments in the laboratory, combined with studies of the fossil record and ways of dating events in the remote past. 

When NSS s together with LKD s are adopted as working tools, both structures appear to trigger some sort of thinking machine, in such a way that once a given problem is solved, new study areas immediately appear to be a promising future application field in the focus of the imagination eye. 

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