Evidence of phase separation in magnetic colloids using magnetic resonance

被引：4

作者：

Neto, KS ^{[1
]}

Bakuzis, AF

Gonçalves, GRR

Pelegrini, F

Morais, PC

机构：

[1] Univ Brasilia, Inst Fis Nucleo Fis Aplicada, BR-70919970 Brasilia, DF, Brazil

[2] Univ Fed Goias, Inst Fis, BR-74001970 Goiania, Go, Brazil

[3] Ctr Univ Brasilia, UniCEUB, BR-70790075 Brasilia, DF, Brazil

来源：

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS | 2005年 / 289卷

关键词：

magnetic liquids; fine particle systems; magnetic resonance;

D O I：

10.1016/j.jmmm.2004.11.038

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Magnetic resonance of a surfacted magnetite-based magnetic fluid was investigated in a temperature range from 100 to 300 K. The magnetic resonance spectra were discussed in terms of contributions due to magnetic centers from isolated nanoparticles and dimers. The magnetic resonance data showed two distinct transitions. One due to a solid-liquid transition around 180 K for the colloid liquid carrier, whereas the second one near 240 K was attributed to phase separation. The spectra area analysis strongly supports our conclusions and additionally suggests the formation of agglomerates prior to the phase separation. (c) 2004 Elsevier B.V. All rights reserved.

引用

页码：129 / 132

页数：4

共 23 条

[1] PHASE-DIAGRAM OF AN IONIC MAGNETIC COLLOID - EXPERIMENTAL-STUDY OF THE EFFECT OF IONIC-STRENGTH [J].

BACRI, JC ;

PERZYNSKI, R ;

SALIN, D ;

CABUIL, V ;

MASSART, R .

JOURNAL OF COLLOID AND INTERFACE SCIENCE, 1989, 132 (01) :43-53

[2] Zero-field birefringence in magnetic fluids: Temperature, particle size, and concentration dependence [J].

Bakuzis, AF ;

Da Silva, MF ;

Morais, PC ;

Olavo, LSF ;

Neto, KS .

JOURNAL OF APPLIED PHYSICS, 2000, 87 (05) :2497-2502

[3] Surface and exchange anisotropy fields in MnFe2O4 nanoparticles:: Size and temperature effects [J].

Bakuzis, AF ;

Morais, PC ;

Pelegrini, F .

JOURNAL OF APPLIED PHYSICS, 1999, 85 (10) :7480-7482

[4] Direct observation of dipolar chains in iron ferrofluids by cryogenic electron microscopy [J].

Butter, K ;

Bomans, PHH ;

Frederik, PM ;

Vroege, GJ ;

Philipse, AP .

NATURE MATERIALS, 2003, 2 (02) :88-91

[5] EQUILIBRIUM PROPERTIES OF FERROCOLLOIDS [J].

BUYEVICH, YA ;

IVANOV, AO .

PHYSICA A, 1992, 190 (3-4) :276-294

[6]

CULLITY BD, 1972, INTRO MAGNETIC MAT

[7] Visualisation of particle association in magnetic fluids in zero-field [J].

Donselaar, LN ;

Frederik, PM ;

Bomans, P ;

Buining, PA ;

Humbel, BM ;

Philipse, AP .

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 1999, 201 :58-61

[8] Structural analogy between aqueous and oily magnetic fluids [J].

Dubois, E ;

Cabuil, V ;

Boué, F ;

Perzynski, R .

JOURNAL OF CHEMICAL PHYSICS, 1999, 111 (15) :7147-7160

[9] Magnetic resonance of zinc- and copper-ferrite ionic magnetic fluids:: temperature effects [J].

Gonçalves, GRR ;

Pereira, AR ;

Bakuzis, AF ;

Neto, KS ;

Pelegrini, F ;

Morais, PC .

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 2001, 226 (PART II) :1896-1898

[10]

GONCALVES GRR, UNPUB J MAGN MAGN MA

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