area of wetted surface
61Egyptian faience — is a non clay ceramic displaying surface vitrification which creates a bright blue green luster. It is called Egyptian faience to distinguish it from Faience which refers to the ambiguous term frit and a type of pottery now know as majolica: a… …
62Motorsport marshal — Track marshals in Britain, in this case waving a red flag Motorsport marshals contribute to more enjoyable, more efficient, and safer motor racing. They are responsible for the safety of competitors and are stationed at various points of danger… …
63No-dig gardening — is a non cultivation method used by some organic gardeners. The origins of no dig gardening are unclear, and may be based on pre industrial or nineteenth century farming techniques.[1] Two pioneers of the method in the twentieth century included… …
64Bentonite — is an absorbent aluminium phyllosilicate generally impure clay consisting mostly of montmorillonite. There are a few types of bentonites and their names depend on the dominant elements, such as K, Na, Ca, and Al. As noted in several places in the …
65Aspect ratio (wing) — In aerodynamics, the aspect ratio of a wing is defined as the square of the wing span divided by the wing area.:AR = {b^2 over S}where: b is the wing span, and: S is the wing area.Informally, a high aspect ratio indicates long, narrow wings,… …
66Concentric tube heat exchanger — Concentric Tube (or Pipe) Heat Exchangers are used in a variety of industries for purposes such as material processing, food preparation and air conditioning.[1] They create a temperature driving force by passing fluid streams of different… …
67zinc processing — Introduction preparation of the ore for use in various products. Zinc (Zn) is a metallic element of hexagonal close packed (hcp) crystal structure and a density of 7.13 grams per cubic centimetre. It has only moderate hardness and can …
68Components of jet engines — Diagram of a typical gas turbine jet engine. Air is compressed by the fan blades as it enters the engine, and it is mixed and burned with fuel in the combustion section. The hot exhaust gases provide forward thrust and turn the turbines which… …
69Hair care — is an overall term for parts of hygiene and cosmetology involving the hair on the human head. Hair care will differ according to one s hair type and according to various processes that can be applied to hair. All hair is not the same; indeed,… …
70Hydroponics — (from the Greek words hydro (water) and ponos (labour) is a method of growing plants using mineral nutrient solutions, without soil. Terrestrial plants may be grown with their roots in the mineral nutrient solution only or in an inert medium,… …
