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Refractories are used in furnaces and boilers that process steel, cement, or glass as well as incinerators that operate at high temperatures. A variety of binders is used when refractories are manufactured. In this chapter, the use of phenolic resin as a binder for refractories is described. There are several factors that support the use of phenolic resins in comparison to other refractory binders. These include the following: 1. Both adhesion and green body strength are high. 2. It is a thermosetting resin system whose strength on curing is high, and the size and stability of the resulting refractory component are good. 3. The ratio of fixed carbon is high and maintains high strength on carbonization. Phenolic resins are the preferred binder for carbon containing refractories. 4. The hazardous properties and industrial environmental issues are lower than those associated with the use of pitch binder.

As a primary source of fixed carbon in the biosphere, living plants provide a large arena for interaction with the fungi, particularly in terrestrial biomes, where plants and fungi may comprise the dominant groups of autotrophs and heterotrophs, respectively. Both fossil (Sherwood-Pike and Gray 1985) and molecular (Berbee and Taylor 1992) evidence suggest that such interactions are ancient and have occurred from the time both groups emerged into terrestrial environments. Indeed, primitive plants may have depended on associations with fungi for successful colonization of dry land (Pirozynski and Dalpe 1989). The present volumes (Vol. V, Parts A and B) explore the modes and mechanisms of accommodation which have arisen during the 400–500 million years in which plants and fungi have coexisted. This initial chapter provides both a preview and summary of the themes which emerge in the chapters to follow, focusing on those attributes which are unique in plants and fungi and which have thus molded their interactions during the course of evolution.

Despite obvious differences between fungi and insects, the two groups share some notable characteristics. Both possess chitin-based exteriors, a polymer of n-acetyl glucosamine that is an important structural component of the fungal cell wall and the exoskeleton of insects. Otherwise, chitin has a very restricted distribution among living organisms. Both fungi and insects are heterotrophic, relying upon other organisms as a source of fixed carbon. In addition, reproduction in both generally results in extremely high numbers of relatively small individuals. It is the nutritional and reproductive features that have had great impact upon the partnerships and antagonisms observed between fungi and insects. The aim of this chapter is to present an overview of the broad range of these insect-fungus relationships, highlighting both older, more classical work as well as some of the exciting new approaches.