0428同步年報-2021-全

Neutron Science 087 of the Fe atom in the Fe 3 O 4 standard, IONP, MGNS and MGNS-nanogel carriers displayed an absorbance signal (Fe = 7112 eV) characteristic of the 1 s to 3 d transition ( Fig. 1(a) ). Comparison showed that the XANES results of the carriers were similar to that of the Fe standard spectrum. For Fe, the intensity of the 1 s to 3 d signal of the XANES Fe K-edge was administered by the average coordination number; the oxygen (O) bonds were synchronized to the central Fe cation. The EXAFS fits for the first shell are displayed in Table 1 and Fig. 1(b) , which reveal that the Fe standard, MGNS and MGNS-nanogel have Fe atoms at the center that are coordinated mainly by Fe–O. The standard Fe–O bond distances in Fe 3 O 4 standard, IONP, MGNS, and MGNS-nanogel carriers were 1.96, 1.95, 1.93 and 1.92 Å with coordination numbers 3.71, 3.75, 3.74 and 3.73, respectively. 6 The SANS techniques were applied to confirm the temperature sensitivity of the prepared carriers at temperatures 25, 37 and 42 °C, as displayed in Figs. 2(a) and 2(b) . The transition behavior of the MGNS and MGNS- nanogel carriers upon applying heat was examined. As seen in Fig. 2(a) , there was no difference in the scattering intensity of MGNS carriers at the different temperatures, but, as a function of temperature, an increase in the scattering intensity of the MGNS-nanogel carriers was observed ( Fig. 2(b) ). 6 When the temperature was increased from 25 to 37 °C, an increased order of the MGNS-nanogel carriers was noticed, but, between the temperatures 37–42 °C, there was a slight increase in the order mainly because the nanogel attained its maximum temperature (above LCST = 42 °C). Moreover, such a transition might result from the collapsed structure of the prepared nanogel. 6 (Reported by Kuen-Song Lin, Yuan Ze University) This report features the work of Kuen-Song Lin and his collaborators published in the J. Ind. Eng. Chem. 104 , 93 (2021). TLS 17C1 EXAFS ANSTO BILBY – Small Angle Neutron Scattering • SANS, XANES/EXAFS • Materials Science, Chemistry, Surface, Interface and Thin- film Chemistry, Condensed-matter Physics References 1. R. K. Dani, C. Schumann, O. Taratula, O. Taratula, AAPS PharmSciTech. 15 , 963 (2014). Samples First Shell CN (±0.05) a R (±0.02Å) b ∆σ 2 (Å 2 ) c Fe 3 O 4 Fe–O 3.71 1.96 0.0019 IONPs Fe–O 3.75 1.95 0.0046 MGNSs Fe–O 3.74 1.93 0.0045 MGNS-nanogel Fe–O 3.73 1.92 0.0045 a coordination number; b bond distance; c Debye-Waller factor. Table 1 : Fine-structural parameters of the samples investigated with EXAFS. Fig. 2 : SANS studies of (a) MGNS and (b) MGNS-nanogel carriers at temperatures 25, 37 and 42 °C. [Reproduced from Ref. 6] 2. K. Dehvari, K. S. Lin, S. S. S. Wang, Int. J. Nanosci. Nano- technol. 14 , 361 (2014). 3. R. Cheng, F. Meng, C. Deng, H. A. Klok, Z. Zhong, Biomate- rials 34 , 3647 (2013). 4. Y. Zhang, S. Uthaman, W. Song, K. H. Eom, S. H. Jeon, K. M. Huh, A. Babu, I. K. Park, I. Kim, ACS Biomater. Sci. Eng. 6 , 5012 (2020). 5. X. Lang, W. R. Lenart, J. E. Sun, B. Hammouda, M. J. Hore, Macromolecules 50 , 2145 (2017). 6. S. C. Kunene, K.-S. Lin, M.-T. Weng, M. J. C. Espinoza, C.-M. Wu, J. Ind. Eng. Chem. 104 , 93 (2021).