4. Universal Serial Bus (USB) USB ports are developed to connect keyboard, mouse, printer and many other devices to the PC. They are developed in mid1990’s and gains a tremendous success because no additional knowledge is required to install the devices. USB ports not only communicate between devices and computer but it can also supply electric power to the devices. USB ports are not only limited to computers but it can also be seen mobile phones and video games consoles. USB ports has undergone a lot of advancement since its development in 90’s. It is now available in three different speeds. They are best known for plug and play in the 20th century. It can be attached and detach from the pc without switching it off. They are standardized by group …show more content…
Insulator part is made of combination of plastic and ceramic. Polybutylene terephthalate is used with glass fibre. Shell is made up of phosphorus bronze, nickel silver or high strength copper alloy. They can be operated between -20°c to 85°c. USB connecters are made up of stainless steel, shell with nickel and contact with brass. Outer cover of USB ports are made with polybutylene terephthalate and glass fibre. PBT is used as an insulator in electronic industries. It is thermoplastic polymer and a type of polyester. It is mechanically very strong and can resist temperature up to 150°c. PBT is reinforced with glass fibre to make it more temperature resistant and also it makes it non-combustible. Thirty percent glass with polyethylene terephthalate is also used. Why copper alloy is used in USB ports? Shell part is made of phosphorus bronze which is an alloy of copper. It has very high strength and toughness and also good electrical and thermal conductivity. Nickel and brass is also used because of their high strength. Resistance to corrosion also makes it perfect for use. Silver is also very good material for shell but it is very
The first term that I noted during the movie was Conductive Polymers. Conductive polymers are almost always organic meaning a large class of chemical compounds whose molecules contain carbon. These polymers have extended delocalized bonds which are bonds found in a molecule that do not belong to a single atom or covalent bond. They are conjugated systems of double bonds and in a aromatic systems. The conjugated systems are atoms covalently bonded with alternating single and double bonds. When the electrons are removed or added into the valence bands the electrical conductivity increases. The conductive polymer has a low conductivity until the electron is removed from the valence band called (p-doping) or (n-doping) until it becomes more conductive. The movement of the charges is what is responsible for electrical conductivity. These polymers are plastic which are organic polymers and with mechanical properties such as flexibility and elasticity.
Clarinets are mainly made of African blackwood, metal, or a special hard plastic called ebonite. The keys on the clarinet are made of metal. The mouthpiece is mainly made of ebonite. The ligature is made of metal. The reed...
Made of semi-translucent flexible nylon thermo-plastic with no metal wire or clasps, these dentures allow the color of the patient's gum to show through. Flexite partials are virtually indestructible, rarely require adjusting, and have clasps (made of the same material as...
Metal alloys and precious metals are also used to make certain aspects of a cochlear implant. The electrode arrays that provide electrical stimulation in order to excite neurons are made out of platinum because they have very high corrosion resistance, good biocompatibility, easier to work with than iridium and have low chemical reactivity. On the other hand, metallic alloys like titanium are used to make the casing for the receiver/stimulator. Titanium is suitable for such an application because it is a light material with high corrosion resistance and rigidity and these properties are essential for the material that is going to be used to make the casing (Stöverl and Lenarz, 2009).
Copper has high electrical conductivity and thus also high thermal conductivity. Naval brass which is the alloy of copper has high hardness when compared to all other alloys of copper. It has high electrical resistance, high strength and high corrosion resistance when compared to other alloy of copper. So, it is difficult to fusion welding of copper and naval brass. The major problem of these alloys in fusion welding is the evaporation of zinc during the welding process. At the end of welding, the welded metal becomes porous.
...ect the internal casing. The internal casing of rubber flashlights is usually aluminum for sturdiness, but they can also be plastic. Rubber casings are very useful as they are waterproof and extremely durable.
is a relatively light and cheap metal. It is important that the robot weighs as little as possible, so
Stainless steel is a type of alloy that has a very strong lattice structure (an arrangement/ shape of the crystals or other objects) which in some case can be more beneficial than others depending on the type of application it may be used for. In many cases this structure will make the material more suited to being used in engineering applications such as tools for instance a hammer (stainless steel alloys) , also they can be used for gears, engines, electrical motors and hydraulic systems because the structure makes the material so strong. So when the arrangement of the structure is as above it makes the overall material even stronger which makes it a good for all the applications stated above. I believe its strength and durability are its main properties as these are commonly needed in the engineering industry, although it is also very well known to be used for its corrosion resistance as it is resistant to many types of corrosion. It is used for these properties because the components such as gears need to be strong in order to keep transferring and altering the rotary motion and torque exhibited in the machine that it may be used in, durable to withstand any loads or pressure put onto it and also corrosion resistance to give the components a bigger life span and increase its rate of work throughout its required use.
It all began in 1991, during the time of monumental computing development. DOS had been bought from a Seattle hacker by Bill Gates, for a sum of $50,000 – a small price for an operating system that had managed sneak its way across the globe due to a clever marketing strategy. Apple’s OS and UNIX were both available, though the cost of running either was far greater than that of running DOS. Enter MINIX, an operating system developed from the ground up by Andrew S. Tanenbaum, a college professor. MINIX was part of a lesson plan used to teach students the inner-workings of an operating system. Tanenbaum had written a book on MINIX called “Operating System” and anyone who had picked up a copy would find the 12,000 lines of code that comprised MINIX itself. This was a big issue; due to the fact that all know (well published) operating systems to that point had been well guarded by software developers, thus making it difficult for people to truly expand on operating system mechanics.
It is one of largest group of organic thermoplastic polymers [1] as well as because it’s non-porous or non-polar and odorless material that is used in structural plastics, consumer goods, food packaging and industrial products. Polyolefin states “oil like” and is commonly cited to as thermoplastic or polyalkene has a waxy texture. This type of compound for the most part utilized in the field of research and production in the petrochemical and organic chemistry industries.
The teeth of the zippers are stamped out of metal strips such as brass, aluminum, bronze or nickel silver alloys. The constructions of metal zippers are shown in Figure 13.6.
At the outset, before the advent of user friendly operating systems, computers were run using the operating system CP/M (Control Program for Microcomputers). The program itself looked simple, but the complexity of its use meant that not many fully understood how to use it. As the program was also limited in use, since it was designed for 8-bit systems, a new operating system was needed when 16-bit IBM systems came out.
There are many different types of alloys; some are so common that they carry on a life beyond their metal bases. For example, 65-90% of copper mixed with 10-35% of zinc create the well known alloy brass, which provides increased resistance to corrosion in things like instruments and
There are trade-off between properties of meterials.People chose materials according to desired properties. They prefered steel to iron and stainless steel to steel. Steel has high tensile strength compare to the iron. Stainless steel has some characteristic features that make it very popular in variety applications. It’s corrosion-resistant, durable and dilutable structure make stainless steel very popular in the structure. For all these reasons, stainless steel is very attractive meterials for variety of applications. By using stainless steel, different shape, colour and forms can be
Thousands of years ago calculations were done using people’s fingers and pebbles that were found just lying around. Technology has transformed so much that today the most complicated computations are done within seconds. Human dependency on computers is increasing everyday. Just think how hard it would be to live a week without a computer. We owe the advancements of computers and other such electronic devices to the intelligence of men of the past.