In 1931, Samuel Kistler created aerogel, the least dense solid in the world. Known for its ultra lightweight and incredible insulating ability, recent developments have shown aerogel’s potential in a wide variety of areas. Recently NASA for has used it to insulate Mars rovers and space suits. In addition to this, its extremely low density was utilized to catch dust particles in space, which would otherwise vaporize if they came in contact with solids at high speeds. Its insulating ability combined with its hygroscopic nature allow it to be very useful in both spacecraft and aircraft maintenance, as they keep ice from forming on the wings of the vehicle. Due to its incredible versatility and ultra lightweight, aerogel is a material of the future that will be utilized heavily in years to come.
In the 1930’s Samuel Kistler removed all liquid from a silicon gel to produce an ultra-light material that functioned as an extremely efficient insulator, and named his discovery aerogel. It was initially marketed as an insulator, but due to developments in efficient insulation not being of priority in the 30’s, Aerogel development stalled. In the 1980’s, Aerogel development resumed as energy efficiency became a salient issue in America. (Aerogel Crystal Structure, 2005) Although it was deemed too costly for domestic use as insulation, the development of aerogels for commercial and military use has since taken off.
Aerogel is produced by making a gel out of a desired material such as silicon, and replacing the liquid in a gel with a pure solvent. Then, the liquid in the gel is heated and pressurized so that it enters a supercritical state, where it can expand and compress like a gas, but has the density and thermal conductivity of a liquid. (H...
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... greatly reduce the weight of planes and other military equipment. (DARPA Awards Aspen Aerogels, 2004) Due to their relatively high cost, the main consumers of aerogels are government agencies and large companies.
The incredible capabilities and extreme versatility of aerogels provide a bright future for this technologically advanced material. As space exploration expands, lightweight insulation will be at a premium, and demand for aerogels will grow exponentially. In addition, its applications in the military and environmental uses will keep this material relevant for years to come. I believe that as research and development of aerogels continues, the cost of this material will decline to the point that it will become accessible to the average consumer, and could be used in protective gear or as originally conceived, as a cost efficient insulator for domestic uses.
During World War II (WW2) the aeroplane proved to be the military’s greatest asset. It was dominant as it was versatile. Unlike the tank, boat or even the foot soldier the planes can serve in all areas of one countries military, land, sea and of course the air. They could fight where ever needed. Not only did they attack in dog fights or bombing raids they could go for a surveillance or reconnaissance to assist their forces. They destroyed many enemies industrial plants and provided many ground combat support.
Of all the tensile fibers in the world none has had a greater impact on the world than Kevlar. It is an almost miracle-like fiber that is responsible for saving countless lives today. However, that is what it appears to have done, at least upon the surface. Kevlar is so much more today than when it was first accidently invented. Imagine a world in which there was no Kevlar, no means to protecting soldiers from bullets, no means to protect those phones teenagers are so crazy about today, or to perhaps to create a glorious display of fire dancing. It would be a dull and boring world without Kevlar in it, a material that few of us know about, yet remains everywhere to be seen just in plain sight.
Other materials used for the Canadarm are aramid fibers [1] such as Kevlar [7]. This aerospace material is also used in bulletproof vests [12]. These aramid fibers are fibers in which the chain molecules are highly oriented along the fiber axis, so the strength of the chemical bond can be exploited [1]. Kevlar is also flame resistant [12] which bolds well in space due to the extreme heat from the solar winds. Kapton is another one of the materials used by spacecrafts. This material has the ability to sustain itself and be stable in many different temperatures such as -269 to 400 °C. Since Space is a vacuum the temperature is intense, therefore this material is well suited for counter...
It is five times stronger, yet the same weight as steel. Kevlar Aramid fiber is an improved material, which is an extremely lightweight, man-made organic fiber. Kevlar fiber has a combination of properties, which have made Kevlar a very useful material. These include, high strength, low weight, high chemical resistance and high cut resistance. This material does not corrode or rust and is also unaffected when placed in or under water.
Are we allotting enough funding for aerospace research? At the present time, significant progress in aerospace research will not be made for a long time. It is sad that we don’t place more urgency on such an important field. Yes, there is still research being conducted in the field; however, limited funding prevents significant advancement. The benefits derived from aerospace research should provide enough justification for investing more money in this area. The benefits are not exclusive to sp...
Gels with low gelatin concentrations were fragile and had low mechanical strength. Concentration of gelatin was optimized to be 5% which satisfied the properties of an ideal scaffold for skin tissue engineering. Gelation does not occur in the absence of chemical cross-linker i.e. glutaraldehyde which indirectly indicates the absence of physical cross-linking in gelatin. The mechanical strength of the cryogels increased with increase in gelatin concentrations. It was observed that as the total concentration of polymer precursors was increased from 4% to 8%, glutaraldehyde requirement for synthesizing optimum cryogel decreased from 1.0% to 0.1% (Table 1.1). This result can be better explained by understanding the well studied aspect of cryogelation that in moderately-frozen solutions, dissolved substances concentrate in the regions of non-frozen solvent (un...
...nd suppliers, causing a huge impact on the construction market. Unlike Styrofoam, which can create poisonous gas when heated, X-Aerogel can prevent the building from burning down. Also, other features of Aerogel such as hydrophobicity and shock/soundproof prove that it is less susceptible to damages from natural disasters. In the future where the X-Aerogel is completely commercialized, the market will run with X-Aerogel on the center.
It was invited by Russell G. Slayter in (1932-1933) as a material to be utilized as thermal building insulation.
From the Wright Flyer to the aircraft we fly today, they all started as a dream that later turned into a design. NASA is not sending astronauts into space at the moment, but that has not stopped the engineers at NASA from working on advanced aerodynamic designs and technologies that would help us achieve the dream of traveling farther, faster and higher. Improved materials such as carbon-fiber give an aircraft lighter weight, improved performance and lower fuel consumption. NASA’s newest design in carbon-fiber is called “PRSEUS” (Pultruded rod, Stitched, Efficient, Unitized Structure), a material that will be stronger than current carbon-fiber technology and will greatly reduce the need for rivets and other fasteners that lead to structural fatigue. NASA believes this new material will help Boeing achieve its goal of an aircraft of blended wing design (Sloan, 2011). Boeing has stated that tests for strength and performance on PRSEUS have exceeded their expectations. Boeing is using this new material in their X-48B, a small scale functional ble...
Aerogels are good thermal insulators because they are adept at counteracting the three methods of heat transfer (convection, conduction, and radiation). They are good conductive insulators because they are composed almost entirely from a gas, and gases are very poor heat conductors. Silica aerogel is especially good because silica is also a poor conductor of heat (a metallic aerogel, on the other hand, would be less effective). Aerogels are poor radioactive insulators because infrared radiation passes right through silica aerogel. Aerogels by themselves are hydrophilic, but chemical treatment can make them hydrophobic. If they absorb moisture they usually suffer a structural change, such as contraction, and deteriorate, but this can be prevented by making them hydrophobic.
Believe it or not silica more specifically silicon dioxide has the potential to do good for our earth and provide benefits, there are many uses that come out of silicon dioxide sone of the most common being food where it is used as an additive
Helium is the most difficult of all gases to liquefy and is impossible to solidify at atmospheric pressure. These properties make liquid helium extremely useful as a refrigerant and for experimental work in producing and measuring temperatures close to absolute zero. L...
Monty, J.P., Jones M.B. and Ooi, A., 436-352 Thermofluids 3 – Compressible Flow. Lecture series distributed by the Dept. on Mech. & Manuf. Engineering, University of Melbourne, 2005.
Hydrogels are defined as networks made up of polymer chains which are hydrophilic. They are in some cases found as a solid dispersed in a liquid. where water acts as the medium dispersed. Hydrogels are natural, highly porous or artificial polymeric networks. The hydrophilic structure allows hydrogels to hold the significant amount of water within their three-dimension structural systems. The extensive employment of hydrogel products in some environmental and industrial areas of applications are very high importance. As time passed, natural hydrogels were replaced with artificial ones. This was due to their long service life, the wide variety of the raw chemical resources, high capacity of water absorption, and their stability. Artificial polymers have structures that are well defined and can be modified to produce tailor powerful functionality and degradability. The artificial of hydrogels can also occur from purely artificial components. The artificial hydrogels are stable in conditions of high and sharp temperature fluctuations. Recent research describes hydrogels as a two- or multi-component systems that are made of three-dimensional
Thus, the AP deflagration may be a well controlling factor for propellant burning rate. The deflagration of pure AP has been investigated intensively in an effort to gain a basic understanding of this process and hence of the combustion of rocket propellants which contain AP as the oxidizer. These studies have proceeded along two directions. The first concerned with investigation of pressure, additives and added radiant energy effects on the burning rate. The second study the deflagration process chemistry [33]. AP undergoes self-sustained combustion only at certain pressure ranges, giving rise to pressure limits. The existence of non-deflagration pressure range where steady deflagration does not occur is one of the most interesting aspects of AP deflagration which has so far managed to elude explanation. Generally, such a range is found to be below a certain pressure level known as the low-pressure deflagration limit (LPL) and above a certain pressure level known as upper-pressure deflagration limit (UPL). The LPL has greater practical importance and has been the subject of many studies. On the other hand, the UPL has not been systematically studied and supposed to exist at the upper level of combustion (detonation). According to many investigations, the average value of LPL was detected to be about 20 atm and burning rate under this condition is around 0.2-4.3 cm/s for single AP crystals or high density pellets. It was found that the LPL is insensitive to sample size and inert atmospheres. LPL increases as the (single) particle size is decreased, lowers as pre-heating, rises as pre-cooling, decreases with increasing pellet density and burning surface area [26, 36]. For more understanding, at sufficiently high pressures the energy transmitted from the flame towards the surface maintains the surface temperature above the AP melting point.