#### Filter Results:

- Full text PDF available (13)

#### Publication Year

2000

2016

#### Publication Type

#### Co-author

#### Publication Venue

#### Key Phrases

Learn More

- R Bandyopadhyay, D Liang, +5 authors R L Leheny
- Physical review letters
- 2004

Multispeckle x-ray photon correlation spectroscopy was employed to characterize the slow dynamics of a suspension of highly charged, nanometer-sized disks. At wave vectors q corresponding to interparticle length scales, the dynamic structure factor follows a form f(q,t) approximately exp([-(t/tau)(beta)], where beta approximately 1.5. The relaxation time… (More)

- Samim Ali, Ranjini Bandyopadhyay
- Langmuir : the ACS journal of surfaces and…
- 2013

The dispersion processes of aqueous samples of clay are studied using ultrasound attenuation spectroscopy. The attenuation spectra that are acquired in the frequency range 10-100 MHz are used to determine the particle size distributions (PSDs) for different concentrations and ages of the clay suspensions. Our analysis, using equivalent spherical diameter… (More)

- Debasish Saha, Yogesh M Joshi, Ranjini Bandyopadhyay
- Soft matter
- 2014

The primary and secondary relaxation timescales of aging colloidal suspensions of Laponite are estimated from intensity autocorrelation functions obtained in dynamic light scattering (DLS) experiments. The dynamical slowing down of these relaxation processes are compared with observations in fragile supercooled liquids by establishing a one-to-one mapping… (More)

- R Bandyopadhyay, G Basappa, A K Sood
- Physical review letters
- 2000

The nonlinear flow behavior of a viscoelastic gel formed due to entangled, cylindrical micelles in aqueous solutions of the surfactant cetyl trimethylammonium tosilate (CTAT) has been studied. On subjecting the system to a step shear rate lying above a certain value, the shear and normal stresses show interesting time dependent behavior. The analysis of the… (More)

We explore the origins of slow dynamics, aging and glassy rheology in soft and living matter. Non-diffusive slow dynamics and aging in materials characterised by crowding of the constituents can be explained in terms of structural rearrangement or remodelling events that occur within the jammed state. In this context, we introduce the jamming phase diagram… (More)

– We report the observation of dynamical behaviour in dilute, aqueous solutions of a surfactant CTAT (cetyl trimethylammonium p-toluenesulphonate), below the overlap concentration c ⋆. At these concentrations, CTAT forms cylindrical micelles and shows a pronounced shear thickening transition above a concentration-dependent critical shear rate ˙ γc. An… (More)

- Vinothan N Manoharan, Guruswamy Kumaraswamy, +30 authors Andrea Tao
- Faraday discussions
- 2016

- B Chung, S Ramakrishnan, +4 authors R L Leheny
- Physical review letters
- 2006

We report x-ray photon correlation spectroscopy and diffusing wave spectroscopy studies of depletion gels formed from nanoscale silica colloids in solutions of nonabsorbing polymer following the cessation of shear. The two techniques provide a quantitatively coherent picture of the dynamics as ballistic or convective motion of colloidal clusters whose… (More)

Several surfactant molecules self-assemble in solution to form long, cylindrical , flexible wormlike micelles. These micelles can be entangled with each other leading to viscoelastic phases. The rheological properties of such phases are very interesting and have been the subject of a large number of experimental and theoretical studies in recent years. We… (More)

- Prakhyat Hejmady, Ranjini Bandyopadhyay, Sanjib Sabhapandit, Abhishek Dhar
- Physical review. E, Statistical, nonlinear, and…
- 2012

The Brazil nut effect is the phenomenon in which a large intruder particle immersed in a vertically shaken bed of smaller particles rises to the top, even when it is much denser. The usual practice while describing these experiments has been to use the dimensionless acceleration Γ = aω(2)/g, where a and ω are, respectively, the amplitude and the angular… (More)