Complexity, history

The aerospace field is a broad one and has a complex history. A comprehensive review of structural adhesive applications on currently flying aerospace vehicles alone could fill its own book. Hence this chapter will concentrate on the aerospace commercial transport industry and its use of adhesives in structural applications, both metallic and composite. Both primary structure, that is structure which carries primary flight loads and failure of which could result in loss of vehicle, and secondary structure will be considered. Structural adhesives use and practice in the military aircraft and launch vehicle/spacecraft fields as well as non-structural adhesives used on commercial aircraft will be touched on briefly as well. 

Daoism, as the primary indigenous religion of China, is a highly esoteric tradition. Constructed of many different strands, over several thousand years, Daoism has a complex history of integrating various techniques of meditation, spirit communication, consciousness projection, bodily movements, medicine, and "internal alchemy" with a profound transpersonal philosophy of nature and a metaphysics of human relationships based on an ideal of spiritual transformation leading to immortality... 

The four tribes are sufficiently differentiated (70) however, the generic limits and nomenclature in the tribe Tabemaemontaneae have had a confusing and exceedingly complex history (11), having been the subject of discussion for more than a century. The number of genera recognized within the tribe has varied... 

Chondrites are the oldest and most primitive rocks in the solar system. They are hosts for interstellar grains that predate solar system formation. Most chondrites have experienced a complex history, which includes primary formation processes and secondary processes that inclnde thermal metamorphism and aqneons alteration. It is generally very difficult to distinguish between the effects of primary and secondary processes on the basis of isotope composition. Chondrites display a wide diversity of isotopic compositions including large variations in oxygen isotopes. 

Considerable geochemical and isotopic evidence has accumulated supporting the concept that many parts of the mantle have experienced a complex history of partial melting, melt emplacement, crystallization, recrystallization, deformation, and metasomatism. A result of this complex history is that the mantle is chemically and isotopically heterogeneous. 

Rocks in the Assejmi core indicate that the allevardite transition occurs at 3Km depth and 150°C. However, these rocks contain the assemblage allevardite + pyrophyllite + chloritoid. The latter phase is typical of metamorphic rocks. Obviously the rocks had a more complex history than is apparent. Other deep cores, up to 5Km in depth reported by Dunoyer de Segonzac (1970) Perry and Hower (1970, 1972) Iijima (1970) and Hower, et al , (1976) show no signs of destabilization of allevardite at temperatures as high as 180°C. 

We will finesse here the long and important struggle of getting a truly self-consistent table of atomic weights. If you are interested in the complex history of this problem and the clear solution to it proposed by S. Cannizzaro in 1860, there are many accounts available in books on the history of chemistry. One example is J. R. Partington, A History of Chemistry, Vol. IV, Macmillan, London, 1964. Relative atomic weights now are based on 12C =12 (exactly). 

Fine AM. 2000. Oligomeric proanthocyanidin complexes history, structure, and phytopharmaceutical applications. Altem Med Rev 5 144-151. 

Tropane alkaloids, principally hyoscyamine and hyoscine, are also found in two other medicinal plants, scopolia and mandrake, but these plants find little current use. Scopolia (Scopolia carniolica Solanaceae) resembles belladonna in appearance, though it is considerably smaller. Both root and leaf materials have been employed medicinally. The European mandrake (Mandragora officinarum Solanaceae) has a complex history as a hypnotic, a general panacea, and an aphrodisiac. Its collection has been surrounded by much folklore and superstition, in that pulling it from the ground was said to drive its collector mad due to the unearthly shrieks emitted. The roots are frequently forked and are loosely likened to a man or woman. Despite the Doctrine of Signatures, which teaches that the appearance of an object indicates its special properties, from a pharmacological point of view, this plant would be much more efficient as a pain-reliever than as an aphrodisiac. 

Escriva H, Manzon L, Youson J, Laudet V. Analysis of lamprey and haghsh genes reveals a complex history of gene duplications during early vertebrate evolution. Mol Biol Evol 2002 19 1440-1450. 

The carbon chemistry of the regolith has been established as a significant indicator of exposure and reworking. In conjunction with other parameters indicative of exposure of the fines and breccias on the lunar surface, it should contribute to an understanding of the complex history of the regolith. 

A handful of L-chondrites have the low contents, < 0.4 X 10 cm STP g associated with an exposure age of 1 Myr or less, namely, Farmington (L5), Pampa (L4), Shaw (L6-7), and Ladder Creek. Herzog et al. (1997) concluded that Ladder Creek had a complex history, but found no evidence for one in Shaw. Marti and Matthew (2002) conclude that Farmington, too, had a simple exposure history in the sense that the material was deeply shielded until —25 kyr before the present. 

Loubet M. and AUegre C. J. (1982) Trace elements in orogenic Iherzolites reveal the complex history of the upper mantle. Nature 298, 809-814. 

Four cratonic, ultradeep xenoliths from S. Africa and Sierra Leone have been analyzed for their strontium and neodymium isotopic compositions (Macdougall and Haggerty, 1999). The neodymium isotopic compositions of minerals from these xenoliths suggest that they were emplaced into the African lithosphere at times ranging from approximately the time of kimberlite emption to hundreds of millions of years earlier. The samples show a complex history of melt... 

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