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• The basketballs themselves are lined with thermoplastic
polyurethane, which helps resist damage caused by oxidation and
hydrocarbon solvents. Also, chemistry-based technologies aid in
the grip, performance, and pressure retention of the balls. In order
to cushion the forces of athletes on the playing surface, floors often
have ethylene propylene diene monomer rubber shock absorbers.
• Many types of sports equipment rely heavily on chemistry to help
athletes reach peak performance—and provide critical safety and
protective functions along the way. Whether it’s a tennis ball or
baseball bat, elite athletes from around the world depend on the
products of chemistry.
• Polyurethanes, a kind of plastic, will play an important role this
summer as they are frequently found in running and other
athletic shoes, making them more resilient. In addition,
polyurethane is found in a wide variety of popular sporting
equipment, such as soccer balls, binders on running tracks
and judo mats.
• A number of styles of sport flooring and pour-in-place track
surfaces use polyurethanes, as well. These equipment
necessities alongside such items as surfboard, roller blades,
bowling balls and spandex apparel are all made possible in
part due to polyurethane innovations
• The shoes worn by the athletes are
also made of thermoplastic
polyurethanes, which provide both
toughness and flexibility. This article
highlights how prevalent chemistry
is in the real world.
- is also changing the way we play sports.
• For instance, nanotechnology
used in golf balls can greatly
improve performance by
reducing hooks and slices.
Tennis racquets manufactured
with nanomaterials become
stiffer and lighter, giving athletes
faster returns and more
powerful serves. And for the
javelin throw or archery, rosin
bags, which are derived from
pine chemicals and also used
by pitchers in baseball and
softball, provide a strong grip.
Chemists have
always played a
fundamental role in the dramatic
advance of electronics.
•electronics are inseparably tied to
chemistry, or that their manufacture
relies on some of the most
demanding chemistry practiced at
• Moore's Law: The observation,
made by Gordon Moore in
1965, that the density of
transistors on a microchip
doubles every two years. Actual
performance would be
expected to increase as, or
more, quickly.
The Junction Transistor
Transistors are fundamentally three-terminal
devices. On a bi-polar junction transistor (BJT),
those pins are labeled collector (C), base (B),
and emitter (E). The circuit symbols for both the
NPN and PNP BJT are below: The only difference
between an NPN and PNP is the direction of the
arrow on the emitter.
• A bipolar junction transistor consists of three regions of doped
semiconductors. A small current in the center or base region can
be used to control a larger current flowing between the end
regions (emitter and collector). The device can be characterized
as a current amplifier, having many applications for amplification
• Vacuum tubes were also used in radios, televisions, radar
equipment, and telephone systems during the first half of
the 1900s. In the 1950s, the transistor started to replace the
vacuum tube. Today, vacuum tubes are no longer used in
• The
tube is a glass
tube that has its gas
removed, creating a
vacuum. Vacuum tubes
contain electrodes for
controlling electron flow
and were used in early
computers as a switch or
an amplifier. The picture
1965, Gordon Moore predicted that the
number of transistors on integrated circuits
would double approximately every two
years, making computers faster and more
powerful. His statement, named Moore's
Law, remains true at the time of publication.
It was the ease and flexibility of silicon that
made this kind of rapid development
Silicon is not the only semiconductor; carbon
and germanium also have similar properties.
Carbon, in its diamond form, is too brittle to
use in chips. Germanium chips were used
early in the computer era; the element is still
sometimes used in chips today. Silicon,
however, can remain a semiconductor at
much higher temperatures than germanium.
This becomes important when chips are
deployed in computers near other electronic
• Chemistry is the discipline which deals with forming new
substances from different basic materials. For this reason it
can be said that chemistry is inextricably linked with civil
engineering - although this link is not as obvious as that to
Construction supplies for
building and
• Cement limestone and clay are made to react at high
temperatures. The individual elements Ca, Si, O, Al, Fe rearrange
themselves to form reactive cement. When mixed with water this
cement will harden to become hydrated or hardened cement.
• In the production of concrete grit or stone particles as well as
water are added to cement. In order to make the properties of
concrete, e.g. its flowability or hardening speed, meet the special
requirements of a building project, concrete additives are used.
These additives also use chemical processes to change first the
fresh concrete and later on the solid concrete.
Lime mortar or cement mortar - often used as tile adhesives, floor fillers or plaster in
the construction of interiors and the making of facades - are also the result of
chemical reactions.