| Full text | |
| Author(s): |
Perigo, E. A.
[1]
;
Silva, S. C.
[2]
;
de Sousa, E. M. B.
[3]
;
Freitas, A. A.
[3]
;
Cohen, R.
[4]
;
Nagamine, L. C. C. M.
[4]
;
Takiishi, H.
[2]
;
Landgraf, F. J. G.
[1, 5]
Total Authors: 8
|
| Affiliation: | [1] Inst Technol Res, Ctr Proc & Prod Technol, BR-05508901 Sao Paulo - Brazil
[2] Nucl & Energy Res Inst, Ctr Mat Sci & Technol, BR-05508000 Sao Paulo - Brazil
[3] Ctr Dev Nucl Technol, Nanotechnol Serv, BR-31270970 Belo Horizonte, MG - Brazil
[4] Univ Sao Paulo, Inst Phys, BR-05315970 Sao Paulo - Brazil
[5] Univ Sao Paulo, Polytech Sch, BR-05508030 Sao Paulo - Brazil
Total Affiliations: 5
|
| Document type: | Journal article |
| Source: | Nanotechnology; v. 23, n. 17 MAY 4 2012. |
| Web of Science Citations: | 10 |
| Abstract | |
Nanoparticles were prepared from a NdFeB-based alloy using the hydrogen decrepitation process together with high-energy ball milling and tested as heating agent for magnetic hyperthermia. In the milling time range evaluated (up to 10 h), the magnetic moment per mass at H = 1.59 MA m(-1) is superior than 70 A m(2) kg(-1); however, the intrinsic coercivity might be inferior than 20 kA m(-1). The material presents both ferromagnetic and superparamagnetic particles constituted by a mixture of phases due to the incomplete disproportionation reaction of Nd2Fe14BHx during milling. Solutions prepared with deionized water and magnetic particles exposed to an AC magnetic field (H-max similar to 3.7 kA m(-1) and f = 228 kHz) exhibited 26 K <= Delta T-max <= 44 K with a maximum estimated specific absorption rate (SAR) of 225 W kg(-1). For the pure magnetic material milled for the longest period of time (10 h), the SAR was estimated as similar to 2500 W kg(-1). In vitro tests indicated that the powders have acceptable cytotoxicity over a wide range of concentration (0.1-100 mu g ml(-1)) due to the coating applied during milling. (AU) | |
| FAPESP's process: | 10/08018-8 - Reprocessing of commercial REFeB (RE = Nd or Pr) sintered magnets for preparation of bonded magnets and semi-hard magnetic compounds using hydrogen |
| Grantee: | Élio Alberto Périgo |
| Support type: | Scholarships in Brazil - Post-Doctorate |