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Showing 2 results for X-Ray Diffraction Pattern
Reza Farshbaf Zinati,
Volume 15, Issue 5 (7-2015)
Abstract
In the current work, a modified method of friction stir process (FSP) based on ultrasonic vibration and modified FSP tool design was developed to disperse multi-walled carbon nano-tube (MWCNT) throughout nylon 6 matrix. To this end, Field emission scanning electron microscopy, X-ray diffraction, Vickers’ micro-hardness, and visual inspection were used to evaluate the fabricated nano-composites. Also, a modified design of FSP tool together with ultrasonic vibration were used to improve the impact and efficiency of FSP. Several experiments were conducted to approach an optimum range of FSP parameters (rotational speed and traverse speed). The scanning electron microscopy observations and X-ray diffraction patterns (XRD) declare that MWCNT was dispersed homogeneously throughout nylon 6 matrix. Micro-hardness results illustrate that homogeneous dispersion of MWCNT throughout nylon 6 matrix results in 33% increase of micro-hardness. In general, the obtained results declare that ultrasonic vibration causes an increase in traverse speed and production speed of nano-composite without affecting the homogeneous dispersion and hardness of nano-particles throughout the matrix. Also, it is clear that ultrasonic vibrations did not noticeably affect superficial form of nano-composites due to low traverse speeds used in ultrasonic assisted friction stir process.
Volume 16, Issue 2 (3-2014)
Abstract
Parkia biglobosa starch was subjected to different heat-moisture treatment (HMT) at different moisture contents (15, 20, 25, and 30%) at 110oC for 16 hours. The content of resistant starch (RS) was the lowest (33.38%) in the untreated native Parkia and increased in the samples with HMT-15 (37.79%), HMT-30 (39.64%), HMT-25 (46.63%), and HMT-20 (50.14%), showing significant increase (P < 0.05) in RS following the HMT. There was a reduction in the swelling power and pasting properties of HMT starches, but the solubility of the HMT starches was higher than that of untreated native starch. Differential scanning calorimetry and the changes in the X-ray diffraction (XRD) patterns confirmed the effect of HMT on Parkia starch. Therefore, replacing native Parkia with heat-moisture treated Parkia starch leads to the development of new products from RS-rich powder with high RS levels and functional properties.