Dominant focus

In contrast, geochronological studies on riverine or riparian sediments have been rarely reported (Winkels et al., 1998). Furthermore, it must be noted that the major proportion of these geochemical studies dominantly focused on pre-selected organic and inorganic contaminants such as heavy... 

The teacher/textbook factor Expertise as a source of students difficulties. Teachers are familiar with the relations between domains of meaning and are mentally able to quickly switch between the four domains in a routine and implicit way. However, teachers may switch so fast between the domains that it will hinder students to develop a proper decision when something has meaning in a macro domain and when in another domain. Teachers may also show a dominant focus on meanings in the submicro and symbolic domain only which will hinder students to connect these meaning with those in the macro domain properly (De Jong Van Driel, 2004). 

Coal is used ia industry both as a fuel and ia much lower volume as a source of chemicals. In this respect it is like petroleum and natural gas whose consumption also is heavily dominated by fuel use. Coal was once the principal feedstock for chemical production, but ia the 1950s it became more economical to obtain most industrial chemicals from petroleum and gas. Nevertheless, certain chemicals continue to be obtained from coal by traditional routes, and an interest in coal-based chemicals has been maintained in academic and industrial research laboratories. Much of the recent activity in coal conversion has been focused on production of synthetic fuels, but significant progress also has been made on use of coal as a chemical feedstock (see Coal CONVERSION processes). 

In the present section, attention will focus on the size of fragments created in a violent fragmentation event. The objective will be to explore some theoretical ideas which appear important to the dynamic fragmentation process. The two underlying phenomena that have dominated theoretical efforts in this area of dynamic fracture mechanics are the presence of an inherent flaw structure, and energy balance in the fracture process. 

The reliability of a product is the measure of its ability to perform its intended function without failure for a specified time in a particular environment. Reliability engineering has developed into two principal areas part and system. Part reliability is concerned with the failure characteristics of the individual part to make inferences about the part population. This area is the focus of Chapter 4 of the book and dominates reliability analysis. System reliability is concerned with the failure characteristics of a group of typically different parts assembled as a system (Sadlon, 1993). 

The origin of the preference for the eclipsed conformation of propene can be explained in MO terms by focusing attention on the interaction between the double bond and the n component of the orbitals associated with the methyl group. The dominant interaction is a repulsive one between the filled methyl group orbitals and the filled n orbital of the double bond. This repulsive interaction is greater in the bisected conformation than in the eclipsed conformation. ... 

As polymer chemistry advanced in the 1930s and 1940s, stronger and more durable synthetic adhesives such as early phenol, resorcinol and urea formaldehydes began to supplant natural glues in wood aircraft manufacture. Around this time however, metal began to replace wood as the dominant material for aircraft manufacture. Aerospace adhesives research and development moved on to focus on metals, primarily aluminum, as the substrates of interest. 

Prior studies of dynamic compaction of powders to achieve high density compacts have devoted effort to development of models of localization of mechanical energy on the surfaces of powders to explain observations of local melting. Unfortunately, the models that have been developed are too narrowly focused and do not realistically consider basic materials response aspects of shock-compression processes. The models fail to account for the substantial observations that show results demonstrating that melting is not the universal, dominant process. 

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