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The nucleating effect of silk fibroin nano-disc (SFN) on the crystallization behavior of poly(L-lactic acid) (PLLA) was investigated by simultaneous synchrotron small- and wide-angle X-ray scattering measurements. For the isothermal crystallization at 110 °C from the melt, the induction period of the PLLA specimens containing 1% SFN was reduced compared to that of the neat specimens, indicating the acceleration of the nucleation of PLLA. The final degree of crystallinity was also increased, and the crystallization half-time was decreased, which indicates that the overall crystallization process was accelerated. Furthermore, the final value of the crystallite size (the lateral size of the crystalline lamella) was slightly lower for the specimens containing 1% SFN than that for the PLLA neat specimen, although the crystallites started growing much earlier. However, it was found that there was no effect of SFN on the growth rate of the crystallite size. The lamellar thickening process was also accelerated with a clear overshooting phenomenon with the inclusion of 1% SFN. As for the polymorphism, the α’ phase is dominant with about 96%, but a small amount of the α phase (4%) is found to exist. It was found that the SFN can also accelerate the formation of the minor α phase as well as the major α’ phase.

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Despite the extensive studies of poly(L-lactic acid)(PLLA), the crystallization of PLLA-based materials is still not completely understood. This chapter presents recent developments of crystallization of PLLA-based blends, block copolymers and nanocomposites. The first section of the chapter discusses the acceleration of PLLA crystallization by the inclusion of biobased (solid and liquid state) additives. It was found that the solid state additives work as a nucleating agent while the liquid-state additive works as a plasticizer. Both type of the additives can significantly enhance the crystallization of PLLA, as indicated by crystallization half-time (t0.5) values. Such composites are of great interest as they are 100% based on renewable resources. The second section talks about the enhanced formation of stereocomplex (SC) crystals in the PLLA/PDLA (50/50) blends by adding 1% SFN. It was found that the loading of SFN enhances the formation of SC crystals and it suppresses the formation of HC (homocrystal). The third section deals with confined crystallization of poly(ethylene glycol) (PEG) in a PLLA/PEG blend. The PLLA/PEG (50/50) blend specimen was heated up to 180.0°C and kept at this temperature for 5 min. Then, a two-step temperature-jump was conducted as 180.0°C → 127.0°C → 45.0°C. For this particular condition, it was found that PEG can crystallize only in the preformed spherulites of PLLA, as no crystallization of PEG was found in the matrix of the mixed PLLA/PEG amorphous phase. The last section describes the confined crystallization of PCL in the diblock and triblock copolymers of PLA-PCL. Furthermore, enantiomeric blends of PLLA-PCL and PDLA-PCL or PLLA-PCL-PLLA and PDLA-PCL-PDLA have been examined for the purpose of the improvement of the poor mechanical property of PLLA to which the SC formation of PLLA with PDLA components are relevant.

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The amplification of DNA provides method for gene based specific detection. Besides Polymerase Chain Reaction (PCR), amplification can be achieved by several isothermal techniques. The PCR suffers from various drawbacks like requirement of laboratory and expertise to perform. Loop Mediated Isothermal Amplification (LAMP) of DNA is one of the promising isothermal techniques rapidly gaining popularity among researchers. The technique requires Bst DNA polymerase and a set of four primers recognizing 6-8 regions of target DNA. LAMP technique of DNA gained surprising popularity for amplifying a desired gene at constant temperature between 60-65 °C & maintain a constant temperature can be easily fulfilled by a water bath or a heat block. The LAMP amplification of the desired DNA fragment can be achieved as high as 10 9 copies in merely 30 min with higher specificity as compared with the existing PCR technique. The technique of LAMP averts the use of costly thermal cycler instrument, facilitating establishment of a field-friendly technique and is promising technique for gene detection in a resourcelimited laboratory.

The wavelet transform is widely used in the task of hyperspectral image compression (HSIC). They have achieved outstanding performance in the compression of a hyperspectral (HS) image, which has attracted great interest. However, transform based hyperspectral image compression algorithm (HSICA) has low-coding gain than the other state of art HSIC algorithms. To solve this problem, this manuscript proposes a curvelet transform based HSIC algorithm. The curvelet transform is a multiscale mathematical transform that represents the curve and edges of the HS image more efficiently than the wavelet transform. The experiment results show that the proposed compression algorithm has high-coding gain, low-coding complexity, at par coding memory requirement, and works for both (lossy and lossless) compression. Thus, it is a suitable contender for the compression process in the HS image sensors.