Discrimination of adulteration of samples of Orang Custom Research Paper Help

Discrimination of adulteration of samples of Orang Custom Research Paper Help

Name of organism: The organisms studied in this article are the Morpho butterflies of South America. These species of butterfly have attracted scientific interest due to the brilliant metallic blue colour of their wings, which does not fade even after 100 years [1]. This colouration is the result of interaction between light and the microscopic structure of the wing, a phenomenon known as structural colour. Aspects suitable for biomimicry: Colours can be divided into two types based upon where they come from: chemical colours and physical colours. Chemical colours result from coloured pigments, thus it is the material itself that determines which colour we see. Physical colours, meanwhile, are produced by the structure of the material being observed. This is because the structures of some materials interact with light in different ways, with the resulting colours generated by processes including emission (e.g., light emitting diodes), interference (e.g., soap bubbles and the rainbow colouration on a compact disc) and scattering (e.g., the blue of the sky or the red of a sunset) [2]. However, in order to produce the structural colour imparted by these various physical phenomena, the structure of the materials in question must accord with the range of the wavelength of the visible light; thus the microscopic dimensions of these structures are the critical condition for producing colouration [2, 3]. The structurally colored objects are often iridescent, in which their colors are changing dependent on either the angle of viewing or the angle of light incidence [3,4]. Figure 1: Photograph of a Morpho butterfly [scale:13 cm] (left), the scales on its wings [scale:0.1 mm] (center), and an electron microscope image of the micro-structures of ridges of wings [scale:200 nm] (right) [5]. Morpho butterflies are well known of their iridescence producing from nanosized light- interacting structures in the scales of their wings [6]. The cuticle on the scales of these butterflys wings is composed of nano-sized, transparent, chitin-and-air layered structures. The colours generated by Christmas tree-like structures originates mainly from light interference within a shelf structure on the butterfly scale through quasi-multilayer [7] [fig.1]. Therefore, rather than statically absorb and reflect certain light wavelengths as pigments and dyes do, these structures selectively cancel out certain colors through wavelength interference while reflecting others, depending on the exact structure and interspatial distance between diffracting layers [8]. Interestingly, there are critical differences in perception between human and other creatives. For example, unlike human vision, the vision of birds (the main predators of insects) is composed of 4 primary colors. Moreover, birds can also perceive ultraviolet light, which human cannot perceive. As a result, birds may perceive patterns that are different from those that a human being perceives [1]. The structural colour inspired by Morpho butterflies has a variety of potential applications in variety of fields where colour is important, such as clothes dyes, cosmetics, decorations and paints. This is because structurally coloured materials are not pigmented, so are resistant to discoloration due to chemical change over time [1]. Mimicking the structural colour found in butterfly wings can thus inform the design of novel optical materials, such as man-made anti-reflective surfaces [3]. Furthermore, these nano-sized structures may prove advantageous in the fight against forgery, as they can be used to make bank notes, credit cards, IDs and passports more difficult to fake [8, 7]. The structural colour of the Morpho butterfly has also inspired researchers to produce an artificial thermal sensor with high sensitivity and spatial resolution which can be used to enhance the efficiency of solar cells [5]. Similar biomimicry would allow researchers to utilise the water repellent (hydrophobicity) and self-cleaning qualities of the butterfly s wing surface. As the butterfly s wings are not self-repairing in case of damage, these properties help to protect the wings by reducing the impact of wind, rain, fog, dew and dust [9]. Methods: Structural color is common throughout nature, producing colors based on various physical principles. Therefore, in order to mimic these structural colors their physical principles have to be clarified. For this purpose, a suitable imaging technique is used to reveal the surface morphology and systematic analysis of this phenomenon is needed, using techniques such as structural model analysis and comparison of spectra [1,10]. The structural color of Morpho butterfly have been well studied, its iridescent feature has been investigated after the development of the electron microscopy [1,10]. Moreover, to verify the fact that the blue color is not generated from blue pigment but nanostructures [11].This nanostructure can achieve an extremely high reflection in the range of visible light can be measured using spectrometer [12]. In 2010, Wu et al set up an optical system to measure the reflective spectrum as shown in fig.2. Figure 2. photograph of Morpho butterfly ,The schematic diagram of the experimental optical system [12]. In the experiments, the source emits light that pass through the optical fiber to illuminate the surface of the reference plate (WS-1-SL, a white reflectance standard from Labsphere made from Spectralon) or samples. Thus, the light reflected from the surface is captured by the reflection probe, and then directed into spectrometer. When the experiment is conducted on a sample of Morpho Rhetenor ring s scale, it was found the reflective spectrum in the visible spectra vary between 0.38 to 0.78 ?ªm (Fig.3).the curve in figure.3 shows the relation between the wavelength(X- axis) and the reflectivity efficiency (Y-axis). It was found the peak was located in the range of 450 ~ 460nm with the value of 83%, which corresponds to the wavelength of blue light [12]. Figure 3. Reflective spectrum of Morpho scales [12]. A Japanese group in 2005 was succeed to mimic the structural colours of a blue butterfly by using focused ion beam chemical vapor deposition (FIB-CVD). The fabricated quasi-structure produced by this technological method was with only some micrometers square. Moreover, the brilliant blue color reflected from the fabricated structure was observed using an optical microscopy. By comparing the reflection spectra from both the real and fabricated Morpho butterfly structures using a photonic multichannel spectral analyzer system, it is found that they are similar [3,2]. The refractive index of scale materials was determined by index matching methods [10]. Furthermore, the structure of Morpho rhetenor scale have been replicated using high- magnification transmission electron microscopy (TEM) images of sample cross sections and subsequent laser-sintering or rapid-prototyping manufacturing processes. The replication model of polymer materials was larger than the natural structure dimensions. The imitation model of the Morpho-butterfly scale was produced at the millimeter and centimeter scale while the natural sample at nano and micro-structures. However, this model produce color using microwave wavelengths due to the effect of electromagnetic scattering phenomena [4] as shown in fig.4. Figure. 4 (a) Large replica model made of polymer produced by subsequent laser-sintering (b) the TEM cross section through a Morpho rhetenor butterfly wing scale. Scale bars: (a) 1.5 cm and (b) 800 nm [4]. State of the art/stage of developments: The brilliant blue wings of the Morpho species are some of the most well-known examples of structural colour. The mystery of this butterfly s color hidden in the nanostructure of its scales was first observed by Anderson and Richards with the use of an electron microscope, and followed by extensive scientific investigations have been performed to explain the principles of their coloration using both transmission and scanning electron microscopes [13]. Figure. 5 Schematic drawing showing the structure on the surface of a Morpho scale. This stylized drawing does not show the irregularities in the natural structure, such as ridges that are bent, of different heights, and have rounded lamellae [10]. The dorsal surface of a butterfly wing is composed of a large number of overlapping scales with dimension of 100 ?? 200??2. These scales have microscopic features with dimensions shorter than the wavelengths of visible light. Each scale consist of ridges which are parallel to each other and separated with a distance typically less than 1 ?ªm, as shown in Fig.5 . Each ridge is seen to be formed of a stack of long, thin plates called lamellae. For the different species of Morpho butterflies, the lamellae within a stack may get thinner in the top [10]. The dorsal (upper) wing surfaces of Morpho butterflies display their brilliant blue hue when illuminated from directly overhead. This colour changes dependent on the angle of illumination or viewing angle. For instance, the iridescence of a Morpho butterfly disappears when the viewing angle is increased; first the dorsal wing scales become mostly transparent, then the more heavily pigmented scales on the ventral (lower) surface of the wings become visible [4]. Studies using electron microscopes have revealed that this blue colour arises from densely packed layers of ridges that cover the scales on the wing surface. This multi-layered structure is composed of alternating layers of high (cuticle, n= 1.56) and low (air, n=1) refractive index materials. When visible light interacts with these ridges, the multiple rays reflected off them interfere with each other and produce the iridescent effect. These overlapping rays are amplified in some wavelengths and attenuated in others according to structural features (wavelength-selective scattering of light) [5, 10]. Furthermore, the wings appear blue even when viewed from too wide an angle (more than ¤40 ?? from the normal range); this phenomenon was explained by the diffraction of light in small width of the shelf. The existence of both regular and random layers in terms of height and plane structures protects the multi-coloured effect. The small gap between the ridges generates a high level of reflectivity [10,14]. Figure 6. Schematic of the Morpho-blue wing microstructure in (a) side and (b) top view: (1) Interference in a single multilayer . (2) Diffraction on narrow structure. (3) Randomness in height prevents the multicolor. (4) Narrow gap results in high reflectivity. (5) Quasi-1D structure contains both the in-plane randomness and line shapes [10]. This model has been experimentally verified by fabricating the model using atomic layer deposition (ALD) technique, and testing its optical properties at nanoscale. An optical film was fabricated by deposited a multilayer composed of alternating layers of high and low refractive index materials on a nanopatterned surface. The deposition layers composed of seven bilayers of titanium dioxide layer that has high refractive index and thickness with around 40nm and then sprayed layers of silicon dioxide that has low refractive index layer, and thickness around 75nm over them as shown in fig 6(a). Oxides were the selected materials for the multilayer deposition due to their wide range of refractive indices and in order to control their thickness easily. Moreover, to produce the desired surface pattern, conventional electron beam lithography and dry etching were applied to quartz substrates fig. 6a. The resulting film had just the right mix of regularity and randomness to have the maximum reflection at 450nm (blue color) [15,2]. Figure 6. (a) SEM image of a quasi-1D pattern fabricated by conventional electron beam lithography on a quartz substrate before multilayer deposition. (b) Schematic of the multilayer fabricated by depositing TiO2 and SiO2 layers on the structure (a) to mimic the mechanisms presented in figure 5 [10]. Problem and limitations: Technological methods used for mimic the structural color of butterfly s wing have limitations. For example, focused ion beam chemical vapor deposition FIB is expensive and time consuming, whereas atomic layer deposition ALD has a limited control and is hardly suited for mass production because it uses the mold (protein) made from the real butterfly scale [2]. It is difficult to produce the structural color material in large scale. It is not commercially available Generally, the structural color is very common in nature, where the colors are produced according to different physical principles. However, many of these principles have still not been clarified [1]. Is it nano? Yes, it is The structural color in Morpho butterfly is produced as a result of interacting visible light ranges between 400 to 700 nm with the nanostructure of scale [ridges of wings [scale 200 nm] [5]. The brilliant blue color of Morpho buterfly has a wavelength of 450 nm [2]. The mimetic model shown in figure 5b is a nanostructure, where the deposition layers composed of seven bilayers of titanium dioxide layer with thickness around 40nm and then sprayed layers of silicon dioxide with thickness around 75nm over them on a nanopattern. Moreover, another parameter in the model such as the width (W) and the depth (D) of the pattern were set at 300 and 110 nm respectively as fig 6b. Comparison between Morpho and Papilio blumi butterflies in color mechanism: The structural colors in butterflies exhibit some variations based on two different central design principles. The first, defines as class I or Morpho type, the wing scale comprises of a multilayered structure within the discrete ridged structures. The second, defined as to class II or Urania type, here the body of scales is comprised of continues multilayers structure [16,17]. One fundamental feature of class 2 type is the regularly deformation of the multilayers structure, which show concave structure of the scale. This concavity structure of scale was found in many Papilio blumi butterflies, and it cause to produce some particular optical properties, such as polarization and color mixing [16]. According to electron microscope images of the scale structure of both Morpho and blumi butterflies, models were constructed. As shown in Figure 7(a) and (b), both the tree-like (Morpho) and the concave structures (blumi) show multilayer stacks that are made from alternating layers of chitin and air. However, the parameters y1 and y2 (illustrated in Figure 7(a)) were defined to be 60 nm and 140 nm in the tree-like structure, while they were defined to be 70 nm and 160 nm in the concave structure. The variation in these parameters is the reason for the different colours of these two butterflies [18]. Figure.7 The models of P.B.and M.R. (a) the 2D and 3D models of tree-like structure evolved from multilayer (b) the 2D and 3D models of concave structure evolved from multilayer [18] The bright green colored areas on P. blumei wings result from the mixing of two different colors, blue and yellow light when they reflected from different regions of the scales. By using Light microscopy, it was found that the centers of the concavities reflected the yellow light and the edges reflected the blue light. The concavities arranged along the scale and has a diameter of 5 ?10 ?ªm [18] [fig.8]. Figure. 8 Photograph of P. blumei butterflies showing its green color [left][16], scanning electron micrograph showing that the surface of a wing scale is covered with concavities (diameter ??5 ?10?ªm) [right] [18]. As illustrated in Fig. 9a: in the normal incident light, when light is incident on the inclined side will be reflected twice across the concavity, and then reflects backward in parallel to the original incident direction. The reflection peak observed by optical microscopy was located at 480nm which corresponding to the blue color. The yellow color is reflected from the flat sides. Moreover, when light is incident by angle of 45 ?, the reflection peak arising from the flat sides is 480nm (blue color); while the reflection peak arising from inclined sides locating at 600nm (yellow color) (Fig. 9b). Therefore, for both normal and 45 ? incident light, the concavities structure produce yellow and blue colors which mix up to make the green coloration caught by human eyes [16]. Figure.9 Illustration of the coloration mechanism of P. blumei s concavities under normal incident light (a) and 45 ? incident light (b) [16]. References: [1] Saito, A. 2002, ?Mimicry in butterflies: microscopic structure ?. Forma, 17, pp.133 ?139. Available at: http://www.scipress.org/journals/forma/pdf/1702/17020133.pdf. [2] Saito, A. 2012, ?Corrigendum: Material design and structural color inspired by biomimetic approach ?. Science and Technology of Advanced Materials, 13(2), p.1-13. [3] Gebeshuber, I.C., 2009. ?Structural Colours in Biology : Scientific Basis and Bioinspired ?, the role of science and technology to improve the quality of live Technological Applications. pp.1 ?16 [4] Vukusic, P. & Stavenga, D.G. 2009, ?Physical methods for investigating structural colours in biological systems , Journal of The Royal Society Interface, vol. 6, no. Suppl 2, pp. S133-1. [5] Sadeghi, I, 2007. Aphysically based anisotropic iridescence model for rendering Morho butterflies photo-realistically. Available at http://graphics.ucsd.edu/~iman/Morpho/ [6] Siddique, R.H., Diewald, S., Leuthold, J. & H??lscher, H. 2013, ?Theoretical and experimental analysis of the structural pattern responsible for the iridescence of Morpho butterflies , Optics express, vol. 21, no. 12, pp. 14351. [7] Zobl, S. S., Matin, T.R., Majlis, B.Y., Schwerte.T, M. Schreiner., and Gebeshuber.I. 2011, ?Structural Colours in the Focus of Nanoengineering and the Arts : a Survey on State- of-the Art Developments ?, pp.815 ?822. [8] Sustainable Nano, 2015. Mimicking Nature s Nanotechnology: From a butterfly wing to anti- counterfeit technologies. Available at Mimicking Nature s Nanotechnology: From a butterfly wing to anti-counterfeit technologies [9] Chen, G., Q. Cong, Y. Feng & L. Ren , 2004, ?Study on the wettability and self-cleaning of butterfly wing surfaces . Design and nature II, pp 246-251 [10] Smith, GS. 2009, ?Structural color of Morpho butterflies , American Journal Of Physics, 77, 11, pp. 1010-1018, Academic Search Complete, EBSCOhost, viewed 29 March 2015 [11] Shinya, Y, & Shuichi, K. 2006, ?Structural or pigmentary? Origin of the distinctive white stripe on the blue wing of a Morpho butterfly , Proceedings Of The Royal Society B: Biological Sciences, 273, 1583, pp. 129-134, Academic Search Complete, EBSCOhost, viewed 25 March 2015. [12] Wu, W., Shi, T., Liao, G. & zuo, H. 2011, ?Research on Spectral Reflection Characteristics of Nanostructures in Morpho Butterfly Wing Scale , Journal of Physics: Conference Series, vol. 276, pp. 012049. [13] Shinya, Y, & Shuichi, K. 2004, ?Wavelength-selective and anisotropic light-diffusing scale on the wing of the Morpho butterfly , Proceedings Of The Royal Society B: Biological Sciences, 271, 1539, pp. 581-587, Academic Search Complete, EBSCOhost, viewed 27 March 2015 [14] Materials: Butterfly-inspired reflectors 2012, Nature, 485, 7396, p. 8, Academic Search Complete, EBSCOhost, viewed 26 March 2015. [15] Saito, A. et al. 2009, ?Reproduction, Mass-production and Control of the Morpho- butterfly s Blue ,Advanced Fabrication Technologies for Micro/Nano Optics and Photonics II, 7205.Available at: http://spiedigitallibrary.org/proceeding.aspx?doi=10.1117/12.808574 [16] Diao, Y. & Liu, X. 2011, ?Mysterious coloring: structural origin of color mixing for two breeds of Papilio butterflies , Optics express, vol. 19, no. 10, pp. 9232 [17] Wang, W., Zhang, W., Fang, X., Huang, Y., Liu, Q., Gu, J. & Zhang, D. 2014, ?Demonstration of higher colour response with ambient refractive index in Papilio blumei as compared to Morpho rhetenor , Scientific reports, vol. 4, pp. 5591. [18] Baumberg, J.J., Mahajan, S., Kolle, M., Huang, F., Scherer, M.R.J., Salgard-Cunha, P.M., Steiner, U. & Vukusic, P. 2010, ?Mimicking the colourful wing scale structure of the Papilio blumei butterfly , Nature Nanotechnology, vol. 5, no. 7, pp. 511-515


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