Document Detail

Probing of Field Induced Structures and Tunable Rheological Properties of Surfactant Capped Magnetically Polarizable Nanofluids.
MedLine Citation:
PMID:  23210900     Owner:  NLM     Status:  Publisher    
Oil based nanofluid containing surfactant capped magnetite nanoparticles are synthesized by simple co-precipitation approach and their magneto-rheological properties are studied for different magnetic field strengths and volume fractions. We observe a distinct 'plateau-like region' in the shear thinning viscosity curve, under an external magnetic field, possibly due to a peculiar alignment of the chains with respect to the field direction where the structure is stable against fragmentation. The observed plateau regime is reminiscent to that of kinetically arrested gel networks. Interestingly, such a plateau regime has been observed only above certain critical magnetic field when the dipolar interaction strength is much greater thermal energy where the aggregation becomes a non-equilibrium transport limited process. The good collapse of specific viscosity data against Mason number for different magnetic field strengths onto a single curve suggests the dominance of hydrodynamic and magnetic forces on thermal force above a certain magnetic field strength. The observed increase in both static and dynamic yield stresses under the magnetic field confirms the formation of columnar structures that hinder the flow behavior. The hysteresis observed in the magnetic sweep experiments show the inability of the chains to relax within the measurement time. The dynamic measurements confirm that the field induced structures impart elastic behavior to the dispersion, which is found to increase with magnetic field and saturates at higher field strengths.
Leona J Felicia; John Philip
Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2012-12-5
Journal Detail:
Title:  Langmuir : the ACS journal of surfaces and colloids     Volume:  -     ISSN:  1520-5827     ISO Abbreviation:  Langmuir     Publication Date:  2012 Dec 
Date Detail:
Created Date:  2012-12-5     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  9882736     Medline TA:  Langmuir     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Oxidation of DNA followed by conformational change after OH radical attack.
Next Document:  Whole genome phylogenies for multiple Drosophila species.