However, due to complexity of the Nano fluid systems, there is no agreement has been achieved in heat transfer processes. Nano fluids have the following advantages: Nano fluids have broad surface area and more heat transfer rate occurs between particles and base fluids. High dispersal
The technology of enhanced heat transfer has received strong attention over the last 3 to 5 decades. Heat transfer augmentation technique using nanofluids have potential applications in the areas such as refrigeration and air conditioning, automobiles, electronics, power generation, nuclear applications, process industries and chemical industries etc. Large attempts have been made to reduce the size and cost of the heat transfer equipments like heat exchanger in recent years. Most of these methods are based on structural variations, vibration of heated surface, injection or suction of fluid and applying electronic or magnetic fields etc. However applying these enhanced heat transfer techniques are no longer feasible for cooling requirements of future generation of micro electronics systems, since they would result in undesirable cooling systems size and low efficiency of heat
However, the virtual mass force is taken into account in the simulations preformed since including this may enable convergence by making the flow less sensitive to momentum or pressure relaxation factors. The virtual mass force arises when a droplet is accelerated or decelerated and the surrounding fluid is accelerated and decelerated together with the droplet. This means that the droplet seems heavier than it actually is. The simulated spray system does not involve any significant pressure gradient and because of this also the pressure force is neglected. Since the density of the liquid is much larger than the gas density, the buoyancy force of the gas on the droplet will be much smaller than the gravitational force and the buoyancy force is therefore neglected.
Due to the smaller density of the bubble than that of the fluid, it rises because of buoyancy effects. The rising bubble problem is important in several industrial applications such as bioprocessing and waste water treatment since it is a governing factor on sizing and designing reactors and processing systems. The problem of a rising bubble in a Newtonian fluid has been widely studied. However, this problem is still challenging and poorly understood in non-Newtonian fluids. In several studies on bubbles rising in a non-Newtonian fluid, the direction of the fluid velocity near the trailing end of the rising bubble is in the direction of motion.
achieving large productivity gains since the 1990s. This gain has been achieved due to ever-increasing miniaturization of semiconductor processing and memory devices (smaller and faster switches and transistors). Continuing to shrink the dimensions of electronic devices is important in order to further increase processor speed, reduce device switching energy, increase system functionality, and reduce manufacturing cost per bit. What is Nano Technology ? We can say it is Nano science which help us to see and work with things in Nano scale, Nano science and nanotechnology involve the ability to see and to control individual atoms and molecules.
About 40% of new chemical entities currently discovered are poorly water soluble. Solubility enhancement is important parameters which should be considered in formulation development of drug with poor aqueous solubility. For improvement of solubility and dissolution, numerous techniques are available. But, solid dispersion is the most promising method to formulators because of its ease of preparation, ease of optimization, and reproducibility[2]. This may be achieved by incorporating the drug in a hydrophilic carrier material obtaining products called solid dispersions[3].Clopidogrel bisulfate is practically insoluble in water, results in poor dissolution and poor bioavailability (50%), used as potent anti-platelet drug, indicated for the prevention of atherothrombotic events in patients with acute coronary syndromes.
Biopolymer gains a lot of interest because the material can be decomposed naturally. The wide application of biopolymer, ranging from packaging to medical apparatus, also makes the materials very interesting to be investigated. Biopolymer also offers advantage of low cost in the material resources and production. Processing biopolymer with microwave might save some energy due to some advantages offered by the microwave processing. In order to see the possibility of processing biopolymer with microwave, temperature dependent properties of thermosetting resin with natural fiber has to be
Carbon nanotubes have a wide range of uses, and look set to become crucial to several industries from electronics and computers, to strengthened materials to drug delivery and diagnostics. Carbon nanotubes are poised to become a major traded commodity with the potential to replace major conventional raw materials. Nanotechnologies may provide new solutions for the millions of people in developing countries who lack access to basic services, such as safe water, reliable
The arce method does have some drawbacks, The fact that it is hard to up scale the method and also the carbon nanotubes are grown in highly tangled forms. The carbon nanotubes are also mixed with other unwanted metals or other forms of carbon. The other method is chemical vapor deposition, the reaction happens in reaction tube which is also in a furnace heated to 600-900C. The reaction happens because there is a carrier/carbon source mix with an injection of catalyst as aerosol. The mixture goes into the reaction tube and forms a catalyst powder or a thin film.
Furthermore, the lack of aggregation and agglomeration of crystals of pure hydrophobic drugs plays an important role on increasing the dissolution rate. It is surrounded by a carrier in a solid dispersion, which prevents convergence and aggregation of particles. The dissolution rate