Principal Types of Construction

Cyclones are the principal type of gas-solids separator employing centrifugal force, and are widely used. They are basically simple constructions can be made from a wide range of materials and can be designed for high temperature and pressure operation. 

The principal types of shell and tube exchanger are shown in Figures 12.3 to 12.8. Diagrams of other types and full details of their construction can be found in the heat-exchanger standards (see Section 12.5.1.). The standard nomenclature used for shell and tube exchangers is given below the numbers refer to the features shown in Figures 12.3 to 12.8. 

Adhesives. Acrylic emulsion and solution polymers form the basis of a variety of adhesive types. The principal use is in pressure-sensitive adhesives, where a film of a very7 low T (<—20° C) acrylic polymer or copolymer is used on the adherent side of tapes, decals, and labels. Acrylics provide a good balance of tack and bond strength with exceptional color stability and resistance to aging (201,202). Acrylics also find use in numerous types of construction adhesive formulations and as film-to-film laminating adhesives (qv). 

The principal type of shear test specimen used in the industry, the lap shear specimen, is 2.54 cm wide and has a 3.23-cm 2 overlap bonded by the adhesive. Adherends are chosen according to the industry aluminum for aerospace, steel for automotive, and wood for construction applications. Adhesive joints made in this fashion are tested to failure in a tensile testing machine. The temperature of test, as well as the rate of extension, are specified. Results are presented in units of pressure, where the area of the adhesive bond is considered to be the area over which the force is applied. Although the 3.23-cm2... 

The principal types of utensils to be employed are summarized here, it being taken for granted that they must be constructed from a material which does not react with, the substance to be sampled and of dimensions appropriate to the container to be sampled ... 

Wegmann, E. (1911). The design and construction of dams including masonry, earth, rock-fill, timber, and steel structures, also the principal types of movable dams. Wiley New York. 

The civil works construction contractor is the first to arrive on the site. Most of its work will have been completed before contractors of other disciplines can start, for civil works create the physical infrastructure upon which equipment is erected and piping and cabling supported. The principal types of civil works are ... 

Applications. Chromate convrasion coaling treatments are used on five principal types of aluminum parts aircraft and aerospace structural conqxnients, coil (for construction applications such as guttering and siding), extrusions (for window and door fiames), heat exchan parts, and containeis (mainly beverage cans). A considoable amount of aluminum is also used in the automotive industry, but most receives a crystalline phosphate treatment because the aluminum is treated at the same time as the steel fiame. 

Performance data Rather than make available principally sales type of data, the architect should review realistic and understandable technical data. They should learn that the behavior of certain plastics provide for more cost-efficient products rather than just be contented with only past history on the materials of construction. 

Whereas DNA has a single role as the storehouse of genetic information, RNA plays many roles in the operation of a cell. There are several different types of RNA, each having its own function. The principal job of RNA is to provide the information needed to synthesize proteins. Protein synthesis requires several steps, each assisted by RNA. One type of RNA copies the genetic information from DNA and carries this blueprint out of the nucleus and into the cytoplasm, where construction of the protein takes place. The protein is assembled on the surface of a ribosome, a cell component that contains a second type of RNA. The protein is consfructed by sequential addition of amino acids in the order specified by the DNA. The individual amino acids are carried to the growing protein chain by yet a third type of RNA. The details of protein synthesis are well understood, but the process is much too complex to be described in an introductoiy course in chemistry. 

The design type refers to variations in equipment configuration (e.g., fixed head versus floating head in a heat exchanger). The adjustment for material of construction is used principally to account for the use of alloy steel instead of carbon steel. The pressure rating factor allows adjusting costs for pressures other than the refer-... 

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