Surface combustion burners or radiant tile burners in comparison produce nitrogen oxides' levels 60-70% less. Therefore John Joyce's research into low NO x burners revolved primarily around surface combustion techniques. Another issue was the effect combustion temperatures have on the formation of NO x.
soup sandwich. A slang term used by members of the United States Army to describe a fellow soldier whose performance is unsatisfactory. This term is often shortened to just soup.. The term expresses a state of extreme uselessness, which can be understood by considering the functionality and worth of soup between two slices of bread.
This is a list of notable sandwiches. A sandwich is a dish consisting of two or more slices of bread with one or more fillings between, or one slice in the case of an open sandwich. Sandwiches are a common type of lunch food often eaten as part of a packed lunch.