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Shrinkage

Mold shrinkage is a volume phenoemnon , usually refers to the differnce between the linear dimension of the mold at room temperature and that of the molded part at room temperature within fort-eight hours following ejection

Shrinkage differntials may be due to any of the following conditions:

*Differential Orientation : Oriented material with molecules or fibers aligned or parallel shrinks in a more anisotropic manner than unoriented material.

*Differential Crystallinity: For semicrystalline materials , if some part of the mold cools at a slower rate , than area will have higher crystalline content and hence higher shrinkage

*Differential Cooling: This can ocur when the mold surfaces are at different temperatures.

*Material Characteristic: Copolymers are beter than homopolymers at resisting warpage. Certain types of homopolymers at resisting warpage. Certain types of fillers reduce overall shrinkage and increase stiffness.

(Handbook of molded part shrinkage and warpage ; Jerry M. Fischer ; pg 9-13 , 2003)

Gnome Rotary Engine

To cope with this limitation an engine intended to enhance the cooling performance by rotating the engine together with the propeller was developed . Concevied form this innovative idea was the 1909 Gnome engine.

In the Gnome engine, the piston and clinders rotate at a speed of about 1150 to 1250 rpm. The cranksahft is hollow , through which gasoline and air are supplied , but this engine does not have carburetor. The gasoline , which was gravity-fed , flowed through the inside of the crankshaft , entered the combustion chamber through the intake valve in the psiton crown.

(The romance of engines ; Takashi Suzuki , pg . 210-212 , 1997)

Flocking Coating

After , the profile is taken to an air-conditioned chamber where is passes through one or several electrostatic flock coating units. The viscosty and tempurature of the adhesive and the condition of flock cating determines the success of procedure and require constant monitoring. The flock must be air-conditioned before use . After flock coating , the profile passes through a drying line. Here any remaining solvent is evaporated and adhesive crosslinked.

(Continuous Vulcanisation of Elastomer Profiles ; A. Hill , pg ; 35 , 1997)

Multiplexer

Amultiplexer or MUX , also called a dta selector , is a combinational circuit with more than one input line , one output line and more than one sellection line .There are some multiplexer ICs that provide complementary outputs. Also , multiplexers in IC form almost invariably have an ENABLE or STROBE input , which needs to be active for the multiplexer to be able to perform its intended fuction. A multiplexer selects binary information presents on any one of the input lines , depending upon the logic status of the selection inputs , and routes it to the output line.

(Digital electronics: principles, devices and applications ; Anil Kumar Maini , pg. 269 ; 2007)