Nano materials: An Introduction
The Nano scale size regime (1-100nm) is observed as the intermediate size between macroscopic crystals (bulk materials) and atoms or molecules. Owing to their fixed energy levels and molecular homogeneity, atoms and small molecules have found widespread applications in areas such as remote sensing1, trace detection2, understanding atmospheric chemistry and have been the subject of investigation in mass spectrometry3 and gas phase laser spectroscopy4. On the other hand by varying the composition, patterning and purity of macroscopic crystals, materials with novel electronic, magnetic, optical and mechanical properties have been created which are very different from atoms and molecules of the same composition. The area of this research focuses on a size scale in which at least one of the dimensions is less than 100nm. The high surface area to volume ratio observed in nanomaterials often gives them unique and exciting properties very different from the bulk and atomic size scales and this has been an area of intense scientific research the world over.
Nanomaterial Fabrication:
Extensive research in the past decade has led to novel fabrication techniques for synthesis of nanomaterials with different physical and chemical properties. The two major synthesis routes used are the “top down and the “bottom up” approach. Lithography is a highly developed top down technique which is used to etch Nano scale features in silicon and other semiconductors often used in the electronic industry. On the other hand DNA and RNA are examples of naturally occurring biological systems built using the bottom up approach from amino and nucleic acids. This biological assembly process is known as self-assembly where complex st...
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...dividual atomic moments observed in ferromagnets, antiferromagnets and ferrimagnets are usually aligned along a preferred or easy axis in the absence of an external magnetic field. In order to flip their magnetic moments, the magneto crystalline anisotropy (EA) which scales linearly with core volume must be overcome. Below the critical size, the (EA) is comparable to the ambient thermal energy (kBT), thus causing the magnetic moment of the single domain magnetic NP to fluctuate, and this property is known as superparamagnetism. Magnetic NPs have widespread applications in areas of magnetic recording (if superparamagnetism can be overcome), medical resonance imaging, drug delivery (when functionalized with organic ligands and proteins), hyperthermia and cancer treatment, magnetic-semiconductor core shell nanostructures and future applications in spintronics13.
The small size ranging from 0.1 to 10 micrometres of nanobots make it difficult to be constructed. The process of working atom by atom and molecule by molecule is monotonous work and the miniaturization of synthetic mechanisms to a nanoscale will only be achievable with the advancement of research in metallurgy.
Amandi Hiyare: Before forming my research question, I had a discussion with my research project coordinator “Lisa Pope” who told me that the Flinders nanotechnology research team has been developing microbial catheters. Then on Monday I had an interview with Professor Joe Shapter who told me that your team was leading this project. So I was wondering whether you would be able to provide me with some detailed information about this innovation?
In order to do this a polymer of DNA “unzips” into its two strands, a coding strand (left strand) and a template strand (right strand). Nucleotides of a molecule known as mRNA (messenger RNA) then temporarily bonds to the template strand and join together in the same way as nucleotides of DNA. Messenger RNA has a similar structure to that of DNA only it is single stranded. Like DNA, mRNA is made up of nucleotides again consisting of a phosphate, a sugar, and an organic nitrogenous base. However, unlike in DNA, the sugar in a nucleotide of mRNA is different (Ribose) and the nitrogenous base Thymine is replaced by a new base found in RNA known as Uracil (U)3b and like Thymine can only bond to its complimentary base Adenine. As a result of how it bonds to the DNA’s template strand, the mRNA strand formed is almost identical to the coding strand of DNA apart from these
The study of nucleic acids has now become a fruitful and dynamic scientific enterprise. Nucleic acids are of unique importance in biological systems. Genes are made up of deoxyribonucleic acid or DNA, and each gene is a linear segment, or polymer, of a long DNA molecule. A DNA polymer, or DNA oligonucleotide, contains a linear arrangement of subunits called nucleotides. There are four types of nucleotides. Each nucleotide has three components; a phosphate group, a sugar and a base that contains nitrogen within its structure. The sugar moiety in DNA oligonucleotides is always dexoyribose, and there are four alternative bases: adenine (A), thymine (T), guanine (G), and cytosine (C). The phosphate groups and the deoxyribose sugars form the backbone of each DNA stand. The bases are joined to the deoxyribose sugar and stick out to the side. Both oligomers, DNA and RNA, consist of 5’->3’ phosphodiester-linked nucleotide units that are composed of a 2’-deoxy-D-ribose (DNA) or D-ribose (RNA) in their furanose forms and a heteroaromatic nucleobase (A, T, G, and C; A, U, G, C), and the resulting oligonucleotide chain is composed of a polar, negatively charged sugar-phosphate backbone and an array of hydrophobic nucleobases. The amphiphilic nature of these polymers dictates the assembly and maintenance of secondary and tertiary structures the oligonucleotides can form. In the DNA duplex structure, genetic information is stored as a linear nucleotide code. This code can be accessed and replicated. RNA, or ribonucleic acid, is another structurally related essential biopolymer. RNA differs from DNA in having the sugar ribose in place of the deoxyribos...
This experiment's purpose is to calculate small values (molecular and atomic size) in different phases, such as a gas, liquid, and solid by using practical methods. If the molar mass is known, one can estimate the atomic size through practical measuring techniques with little experimental error. This experiment consists of measuring a block of a solid element (Copper and Zinc), measuring the volume of the lead pellets, and measuring the amount of carbon dioxide gas in a balloon. These experiments will allow one to estimate the atomic or molecular size by using doable measurements and calculations.
...gnetic. This new magnetic state stems from the fact that the spins are interacting by the double exchange interaction. Subsequently the insulating state changes to semiconductor. Furthermore, the general concept is that ferromagnetic materials favours metalicity.
It is clear that nanotechnology has the potential to revolutionize health care and even transport
Chemistry dictates the structure of DNA. DNA is a polymer of monomers called nucleic acids. These are made of a nitrogenous base, a phosphate group and a sugar. It is the negative charge on the phosphate group that makes DNA an acid. There are 4 different bases: adenine, thymine, guanine and cytosine. In groups of three, these four bases can code for any protein coded for in an organism’s genome. Two strands of nucleic acids stack on top of each other in a double helix. The backbone of the nucleic acids consists of the interaction between phosphate groups and the hydroxide groups of nucleic acids. These are held together by covalent bonds called phosphodiester bonds. The helix itself is held together by hydrogen bonds. Although h...
To form a polynucleotide DNA, many nucleotides are linked together with 3`-5` phosphodiester linkages. In a compl...
Nanotechnology is the manipulation of structures at nano levels. It uses incredibly small materials, devices, and systems to manipulate matter. These structures are measured in nanometers, or one billionth of a meter, and can be used by themselves or as part of larg...
23. S. Alwarappan, S. Boyapalle, A. Kumar, C.-Z. Li and S. Mohapatra, J. Phys. Chem. C, 2012, 116, 6556–6559
The main purpose of green nanotechnology has been to develop clean technologies that would minimize potential human and environmental health risk. Also, to encourage replacement of existing products with the clean technologies that is more environmentally friendly. There are many benefits of using green nanotechnologies as the new solution for energy in both their current availability and their current development. Over the new few decades, the highest growth opportunities will come from application of nanomaterials for making better use of existing resources. Nanotechnologies will help reduce weight of carbon emission in transportation utilizing nanocomposite materials that quickly diffuses across the automotive and aerospace industries. Applications of nanotechnologies will result in a global annual savings of 8000 tons of carbon dioxide, which will rise even further to over millions tons by 2020. But, let’s focus on the positive effects of Green Nanotechnology in Solar.
A crystalline material can be either a single crystal or polycrystalline. Material with Polycrystalline consists of many crystals separated by well-defined boundaries whereas a single crystal consists of only one crystal. It is difficult to prepare single crystals when compared to polycrystalline materials, and more effort is needed for the growth of single crystals. There are two main reasons for the intended growth of single crystals. Many physical properties of solids are complicated by the effects of grain boundaries. The full range of tensor relationships between an applied physical cause and an observed effect can be obtained only if the total internal symmetry of the crystal structure is continued throughout the
Alford, Terry L., L. C. Feldman, and James W. Mayer. Fundamentals of Nanoscale Film Analysis. New York: Springer, 2007. Print.
Figure 1: Image of the nanoscale, this illustration shows how small things at the nanoscale really are (nano.gov, 2013).