The cosmetic and consumer industrial sector is a high growth industrial sector roughly valued at $532 billion. Due to consumers’ increasing awareness on product sustainability, microbially produced biosurfactants are increasingly gaining the interest of the home and personal care industry as potential alternatives for traditional petroleum derived and chemically synthesized surfactants. The future of personal care and detergent products is the elimination of non-biodegradable, environmentally toxic surfactants. Additionally, synthetic polymers utilized extensively in these industries for performance enhancement are being replaced by biodegradable biopolymer alternatives. New sustainable ingredients like silk proteins are also showing considerable promise as new high-performance alternatives. However, a move to fully sustainable formulations utilizing novel alternatives will only be successful if the performance criteria such as rheology and surface activity matches or surpasses that obtained from traditional surfactants and polymers. This requires engineering the microstructure and interactions in these formulations and a re-establishment of the microstructure-property-performance linkages in these complex fluid based products. In this talk this approach of engineering the microstructure and interactions for effective product formulation design will be illustrated for a range of sustainable and biodegradable alternatives and their combinations, namely, glycolipids, silk proteins and chitosan. The physico-chemical insights required for establishing the formulation design rules were generated utilizing a range of advanced characterization techniques. These include interfacial rheology, diffusing wave spectroscopy (DWS), raman spectroscopy, dynamic light scattering etc. As will be highlighted in this talk, the combined utilization of these techniques especially diffusing wave spectroscopy, optical microrheology and Raman spectroscopy offers new insights into the mechanisms and pathways of the self-assembly process and understanding of the driving forces associated with changes in viscosity and viscoelasticity in these complex fluids based products.

In this talk, a brief overview of funding opportunities across NSF – including CAREER, Designing Materials to Revolutionize and Engineer our Future (DMREF), NSF-CASIS collaboration, Major Research Instrumentation (MRI), Computational and Data Enabled Science and Engineering (CDS&E), and NSF Research Traineeship (NRT) programs – will be presented. Strategies to write effective research proposals and to communicate with program directors will also be discussed.

Electrospray deposition (ESD) is a well-established technique for the creation of thin films from the spray of highly charged droplets loaded with the materials to be deposited. While a majority of the ESD research has involved the evolution of droplets in the air, the dissipation of charge on arrival at the substrate is critical in determining the final spray macroscale and microscale morphology. Recently, we have categorized various modes of ESD, including self-limiting electrospray deposition (SLED). In SLED, specific manipulation of the electrostatic repulsion, hydrodynamic forces, and evaporation kinetics can be employed to conformally cover 3D architectures with microcoatings. The generated coatings are hierarchical, possessing either nanoshell or nanoparticle microstructure. The initial demonstrations of SLED employed single glassy polymers as the solutes and simple cm-scale geometries as substrates. Here, I will discuss opportunities to create bioactive conformal coatings on medically-relevant architectures by employing blending, self-assembly, and complex geometries. For example, we have (1) added cilia-like nanowires to the collection of achievable morphologies, (2) demonstrated that 3D capabilities increase with decreasing feature size to the micron-scale on hard-soft interfaces, and (3) created living and therapeutic coatings from previously incompatible materials. Further, SLED is a highly scalable and targeted method, thereby removing barriers for integration into advanced manufacturing techniques such as roll-to-roll or additive manufacturing.

https://hmnl.rutgers.edu

1. Lauren Barnes (NJIT), "Resonant interactions in bouncing droplet chains"
2. Yuexin Liu (NJIT), "Training a Stokes swimming using machine learning"
3. Thai Dinh (Stony Brook), "Role of interfacial tension on viscous multiphase flows in coaxial microfluidic channels"
4. Catherine Nachtigal (Rutgers), "Morphological Studies of Electrospray Deposition of Methylcellulose Nanowires"
5. Jiachun Shen (Stony Brook), "The preparation and anti-bacterial performance of polymer-nanoparticle films"
6. Aktaruzzaman Al Hossain (Stony Brook), "Electrokinetic flows and zeta potentials on superhydrophilic and superhydrophobic nanostructured surfaces"
7. Arielle Gamboa (Rutgers), "Morphological Control of Melting Gels via Electrospray Deposition"
8. Ensela Mema (US Military Academy), "A mathematical model for dielectrowetting of nematic liquid crystal films"
9. Tianxing Ma (Rutgers), "Focused laser spike thermocapillary dewetting for metrology of glassy thin films"
10. Shang-Huan Chiu (NJIT), "The Wave Instability in Two-Phase Flows of Non-Newtonian Fluids"

Topological defects play a prominent role in the physics of two-dimensional materials. When driven out of equilibrium in active nematic liquid crystals, defects acquire spontaneous self-propulsion and proliferate to drive self-sustained flows. In this talk I will present an effective model of defects in active nematics as quasiparticles and show that the turbulent-like dynamics observed ubiquitously in these active fluids can be described as a non-equilibrium variant of the Berezinskii Kosterlitz-Thouless defect-unbinding transition. On scales larger than the defect separation, the dynamics of the gas of unbound defects can be described by hydrodynamic equations that provide an excellent framework for treating inhomogeneous activity, as used in recent experiments to harness active flows.

https://marchetti.physics.ucsb.edu

1. Nancy Lu (Princeton), "Forced Imbibition in Stratified Porous Media"
2. Tapomoy Bhattacharjee (Princeton), "Bacterial chemotaxis in porous media"
3. Navid Bizmark (Princeton), "Multiscale dynamics of colloidal deposition in porous media"
4. Chris Browne (Princeton), "Leveraging Polymer Flow Instabilities for Groundwater Remediation"
5. Joanna Schneider (Princeton), "Using colloids to remove immiscible contaminants from porous media"
6. David Cunningham (Rutgers), "The effect of fracture roughness on the onset of non-linear flow"
7. Jean-François Louf (Princeton), "Under pressure: Hydrogel swelling in a granular medium"
8. Richard Castellano (Rutgers), "Fabrication of highly permeable, chem/bio protective carbon nanotube membranes"
9. Da-Chi Yang (Rutgers), "Sub-nanometer Carbon-nanotube Membranes with Anomalously Enhanced Water-vapor Flux"
10. Minglu Li (Rutgers), "Characterization of powder wettability by capillary rise in a closed column"
11. Semih Cetindag (Rutgers), "Enhanced Selective Ion Transport and Osmotic Power Generation in Boron Nitride Nanotube Membranes"
12. Dhiraj Nandyala (Stony Brook), "Design and Fabrication of a capillary diode for potential application in water-oil separation"
13. Nelya Akhmetkhanova (CCNY), "Shear Thickening in Bidisperse Dense Suspensions"
14. Omer Sedes (CCNY), "Stress Fluctuations at the Onset of Discontinuous Shear Thickening"
15. Larry Galloway (UPenn), "Quantification of plasticity via particle dynamics above and below yield in 2D jammed suspensions"
16. Honghu Zhang (Brookhaven NL), "Valence-programmable molecular constructs for controlling assembly of nanoparticle clusters and lattices"
17. Zohreh Jalilvand (CCNY), "Behavior of Pt-coated Silica Janus particles Near Oil/water interface"
18. Akash Banerjee (Rutgers), "Self-Organization of Proteins in Lipid Membranes and Vesicles"
19. Zainab Abd Al-Jaleel (Rutgers), "Filtration of Catalyst Materials"

In this talk, I will discuss recent and ongoing research on the multiphysics response of polymeric gels. A polymeric gel is a polymeric material swollen by a fluid, and the intake or outflow causes large deformations. Also, many gels respond to environmental stimuli such as temperature, electric and magnetic fields, pH, and more. The responsiveness of polymeric gels to environmental stimuli has been widely employed in soft robotics, and the potential applications of soft robots are vast. The fast emerging development of gel-based soft robots makes understanding the mechanics of this class of material an important task for simulating their operation.

The talk begins with recent experimental observations on the mechanical behavior of polymeric gels. Then a continuum level model for the coupled deformation-diffusion response of gels that incorporates anisotropy and inelasticity is summarized. That is followed by model calibration and attempts for validation on relatively simple gels. Numerical simulations are performed to show the behavior of the model, and qualitative comparisons are made to experiments of a soft robotic gripper. Results show that the behavior of polymeric gels is even more dependent on fluid uptake than previously thought.

https://web.njit.edu/~sac3

The ability to organize nano-components into the desired organizations is one of the major limitations for creating material systems from nanoscale objects. Our efforts are focused on establishing a broadly applicable DNA-based platform to address this challenge. We explore novel concepts for creating targeted static and dynamic nano-architectures by bridging DNA-encoded nano-objects with structural plasticity of DNA macromolecular constructs. Through exploring rational assembly strategies and revealing the principles governing these DNA-programmable systems, we develop methods for creation of prescribed three-dimensional lattices, two-dimensional arrays and finite-sized cluster architectures from the inorganic and biomolecular nano-components. Our resent advances in creating inorganic, organic and hybrid nanoscale architectures and their applications for nano-optics and biomaterials will be also discussed.

We perform detailed computational and experimental measurements of the active dynamics of a dense, uniform suspension of sedimented microrollers driven by a magnetic field rotating around an axis parallel to the floor. We develop a lubrication-corrected Brownian Dynamics method for dense suspensions of driven colloids sedimented above a bottom wall. The numerical method adds lubrication friction between nearby pairs of particles, as well as particles and the bottom wall, to a minimally-resolved model of the far-field hydrodynamic interactions. Our experiments combine fluorescent labeling with particle tracking to trace the trajectories of individual particles in a dense suspension, and to measure their propulsion velocities. Previous computational studies [B. Sprinkle et al., J. Chem. Phys., 147, 244103, 2017] predicted that at sufficiently high densities a uniform suspension of microrollers separates into two layers, a slow monolayer right above the wall, and a fast layer on top of the bottom layer. Here we verify this prediction, showing good quantitative agreement between the bimodal distribution of particle velocities predicted by the lubrication-corrected Brownian Dynamics and those measured in the experiments. The computational method accurately predicts the rate at which particles are observed to switch between the slow and fast layers in the experiments. We also use our numerical method to demonstrate the important role that pairwise lubrication plays in motility-induced phase separation in dense monolayers of colloidal microrollers, as recently suggested for suspensions of Quincke rollers [D. Geyer et al., Physical Review X, 9(3), 031043, 2019].

1. Xiaoxi Yu (Stony Brook), "Small-angle X-ray Scattering Study of Cationic Amphiphilic Alternating Copolymers with Tunable Morphology"
2. Benjamin Yavitt (Stony Brook), "Structural dynamics of 3D printed UV curable nanocomposites"
3. Ran Li (Rutgers), "E2 temperature and Gamma distribution of polygonal planar tessellations"
4. Sijie Tong (Princeton), "Viscoelastic properties of tissues in the vertex model"
5. Seyedsajad Moazzeni (Rutgers), "Single-cell mechanical analysis via electrodeformation-relaxation"
6. Arnold Mathijssen (Stanford), "Pathogen clearance by ciliary arrays in the respiratory system"
7. Tejas Dethe (Princeton), "Effect of Symmetry Breaking on Phononic Crystal Band Structures"
8. Darrel Dsouza (Rutgers), "Electrohydrodynamic Thermal Oscillators for Waste Heat Harvesting Applications"
9. Yu Han (CCNY), "Axisymmetric deformation of droplet with an adsorbed surfactant monolayer in a steady electric field"
10. Christine Wang (Brookhaven NL), "Design and Engineering of Synthetic Biomolecular Toolbox for Biosensing and Nanomedicine"

Multiphase and interfacial fluid and biological processes at various scales are key in elucidating pathogen transmission driving, for example, epidemics and pandemics. We discuss how unsteady fluid fragmentation shapes the generation and transport of pathogen-bearing droplets created from contaminated fluids. We give an overview on results from our recent joint experimental and theoretical investigations on the role of unsteadiness in shaping a ubiquitous yet neglected class of fluid fragmentation problems. The implications for human health will be discussed.

http://lbourouiba.mit.edu/