First Nano Car Designed

A group of scientists hailing from Rice University hav now claimed to have developed the world’s smallest car, the nanocar. This driving body has now been described in a research paper that says the car contains a chassis, axles and four buckyball wheels. More details about this nanocar is expected to be published soon in an upcoming issue of the Nano Letters journal. These single-molecule vehicles have a measurement specification of just 4x3 nanometers, this is just a bit wider than a strand of DNA. The car has four buckyball wheels made of 60 atoms apiece and connected to four independently rotating axles and an organic chemical chassis. The developers of this car look at it as some sort of landmark in molecule scale manufacturing. James M Tour, a lead researcher of the project commented, "The synthesis and testing of nanocars and other molecular machines is providing critical insight in our investigations of bottom-up molecular manufacturing. We'd eventually like to move objects and do work in a controlled fashion on the molecular scale, and these vehicles are great test beds for that. They¹re helping us learn the ground rules." The car was evolved after an extensive eight years of. It’s main function in the future will be to carry nano-sized payloads from point A to B.

The Innerworkings of the Transistor

Since transistors are used everywhere today from Computers to Microwaves to Electronic giftcards I thought It might be a good idea to write up an article on how they work to elimate any confusing ideas a begginger in electronics might have.

Now on to how a transistor works. Here is a diagram that I will use to explain this all.

Collector-----


+
+
Gate----------
+
+


Emitter-------

The gate is just another name for the base. Transistors all have a V-be voltage this is the voltage that it takes to turn the transistor on. After it is on it can operate in different modes. Cutoff. This mode is when the voltage through the base and emitter is less than the V-be voltage needed to turn the transistor on. Forward Active. This mode is what amplifiers use in this mode a change in the base current results in a change in the current that is allowed to pass from the collector to the emmiter. The change is a multiple of beta. Most of the time beta is around 100 so the current that flows from the collector to the emitter is 100 times greater than the current going from the base to the emitter. Saturation. This mode is when more current from the base to the emitter produce little change in the current from the collector to the emitter. Saturation is most often used in things that need transistors to switch things on and off.

As you can see here you have a gate by with you can tell thats its going to control the Collector and Emitter. Well when you have a large voltage behind the Collector it collects it and when a small voltage is passed to the Gate it opens the path way for the large voltage can get through and go out of the transistor through the Emitter. In a PNP transistor The N is the gate since its the middle letter and one P is the collector and the other is the Emitter. WHen you apply a voltage to the gate the gate in a PNP turns from a N into a P which unblocks the voltage behind it and in a NPN the gate turns from P to N so the easyest way to know which way your gate is turning is to look at the two outside letters since the gate needs to be the same as them to allow a voltage to go through. Since they both work the same way what would be the sence of having both NPN and PNP transistors, the NPN transistors are for slower electronics that hobbists would use well PNP are much faster transistors that are uses in computers.

One of the problems that we have with transistors is that they can easly be killed by static discharges making a corona of high voltage around the gate with permantly turns the gate on. This is allowed because of Kirchhoff's Voltage law and the weak dielectric strenght between the layers of P's and N's

Breakdown is caused when one tryed to send a reverse voltage through the gate. When a high enough reveresed voltage is applyed the skin effect occures and the transisotr can literaly explode from surface heating.

Transistors like resistors and Inductors can be damage by EMP (Electro Mangetic Pulse) with is basicly a strong mangetic feild the grables up the atoms inside of the electonic parts. Caused by a Induced charge on the dielectics which would just turn your part into a jumper wire.

Transistor Flow Control

At the heart of modern electronics are transistors, which act like valves to direct the flow of electrons. Now researchers at the University of California at Berkeley have created the first transistors that electrically control molecules instead. By connecting them to microscopic test tubes and petri dishes, these nanoscale transistors could lead to labs-on-a-chip that work without moving parts.
Much as 30-ton computers shrank over decades to microchip size, investigators are now miniaturizing labs to run millions of experiments simultaneously and dramatically speed analysis of DNA, proteins and other molecules. Although valves and pumps exist to control flow in microfluidic channels, they are not easy to miniaturize further for use on nanometer levels, says Berkeley mechanical engineer Arun Majumdar.
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Catalyzing Nanotechnology

As scientists and engineers continue to make progress in the realm of nanotechnology, new tools become necessary to synthesize more complicated structures on such tiny scales. UC Berkeley chemical engineer Alexander Katz is developing several techniques to fashion structures that spur specific chemical reactions but are as small as a single nanometer. His processes range from a cookie-cutter templating technique to methods directly inspired by Mother Nature. Eventually, the materials that Katz and his collaborators discover could speed the development of nanoscale electronic components for future computers and related memory systems.

Alexander Katz and his colleagues have a U.S. patent on one of their methods to bind functional groups on surfaces discovered at Berkeley, with two others currently pending.
"Standard lithographic etching used to make microprocessors is certainly able to create mechanical features of the right size and shape," Katz explains. "But as these features become smaller in the future, what becomes as important as their size and shape is local arrangement of chemical functional groups. How can we organize these groups and the environment surrounding them in solids?"
Because of their small size, the structures that Katz's research group synthesizes can be used as active catalytic sites for causing chemical transformations to occur. Chemists use catalysts to speed the rate of chemical reactions. The catalyst acts as a pathway between the reactants and the end product that requires less of an energetic barrier than the transformation would take otherwise. Because the nanoscale order in Katz's sites can interact with a reactant molecule specifically, these sites can induce chemical reactions with great selectivity. For instance, some of Katz's sites can steer the product of a chemical reaction to be one or another molecule, depending on the functional group arrangement. The most proficient examples of how elaborate organization of functional groups can affect catalysis can be found inside of each of us.
"The functional groups that keep us alive consist of relatively simple building blocks," Katz says. "But the way they're assembled is intricate. It's that assembly that imparts elaborate catalytic properties."
Molecular imprinting in silica is a method Katz and his colleagues developed to achieve nanoscale functional group organization in solids. The researchers take a particular molecule and mold silica around it. The molecule is then removed but chemical functional groups are left attached to the inside of the mold. The end result is a solid, visually not unlike an ordinary piece of glass, but actually riddled with miniscule imprinted pores. Organic molecules bind inside these pores where the imprinted functional groups promote a chemical reaction.
The researchers have also explored a method to imprint bulk silica with particle templates as large as 15 nanometers. Rather than organize several functional groups at a time, the synthesis of nanoparticle building blocks for bulk silica imprinting is ideal for organizing thousands of functional groups at once, Katz says.
The process is similar to the single-molecule imprinting, but in this case a nanoparticle with a functional group organized on its surface is bound in the silica. After the nanoparticle core is removed, the organized functional groups remain immobilized in the structure.
In another technique that Katz and his coworkers discovered, bowl-shaped functional groups are grafted to the surface of a piece of silica. The functional groups act as one nanometer-sized "pocket" that only allows certain catalytic reactions to occur. The rim of the pocket and the surface of the silica can also be altered to affect the catalyst properties.
"The mechanism and the selectivity of these reactions, in addition to catalyst activity, can be dictated by our ability to organize chemical functional groups in solids," Katz explains. "All of our efforts are about taking something ordinary, like these functional groups, and enabling them to do extraordinary things when arranged cooperatively within a nanoscale site."
Courtesy:Science matters