journal
MENU ▼
Read by QxMD icon Read
search

Soft Matter

journal
https://www.readbyqxmd.com/read/28819672/folding-sticky-elastica-dynamics-and-reversibility-of-folds-in-langmuir-monolayers
#1
L C Foucard, J M Eaton, M Dennin, Alex J Levine
Lipid monolayers at the air/water interface are often subject to large mechanical stresses when compressed laterally. For large enough compression they fold in the out-of-plane direction to relax stress. The repetitive folding and unfolding of lung surfactant monolayers during breathing plays a critical role in conserving monolayer material at the air/water interface lining the lung. Although the mechanisms behind the folding have been explored recently, relatively little information exists regarding the implications of folding dynamics on the long-term stability of the monolayer...
August 18, 2017: Soft Matter
https://www.readbyqxmd.com/read/28819663/rheological-characterization-of-yield-stress-gels-formed-via-electrostatic-heteroaggregation-of-metal-oxide-nanoparticles
#2
Javen S Weston, Jeffrey H Harwell, Brian P Grady
Mixtures of fumed fractal metal oxide nanoparticles (np's) dispersed in water, at a solution pH where one species is positively charged and the other is negatively charged, form yield stress gels at volume fractions as low as 1.5%, due to electrostatic heteroaggregation into networks as confirmed by small-angle neutron scattering. These gels exhibit a measurable yield stress and an apparent viscosity that follows a power law relationship with shear rate. Rotational and oscillatory shear rheology is presented for binary mixtures of fumed silica, fumed alumina, and fumed titania in aqueous dispersions...
August 18, 2017: Soft Matter
https://www.readbyqxmd.com/read/28819662/chiral-amplification-of-disodium-cromoglycate-chromonics-induced-by-a-codeine-derivative
#3
F Berride, E Troche-Pesqueira, G Feio, E J Cabrita, T Sierra, A Navarro-Vázquez, M M Cid
Chromonic liquid crystals (CLC) are lyotropic phases formed by discotic mesogens in water. Simple chiral dopants such as amino acids have been reported to turn chromonic liquid crystals into their cholesteric counterparts. Here we report a chirality amplification effect in the nematic phase of a 9 wt% disodium cromoglycate (DSCG) lyotropic liquid crystal (LLC) upon doping with a water-soluble codeine derivative. The transition on cooling the isotropic to the nematic phase showed the presence of homochiral spindle-shaped droplets (tactoids)...
August 18, 2017: Soft Matter
https://www.readbyqxmd.com/read/28819659/solvent-hydrophobicity-induced-complex-coacervation-of-dsdna-and-in-situ-formed-zein-nanoparticles
#4
Pankaj Kumar Pandey, Priyanka Kaushik, Kamla Rawat, V K Aswal, H B Bohidar
Zein, a predominantly hydrophobic protein, was sustained as a stable dispersion in ethanol-water (80 : 20, % (v/v)) binary solvent at room temperature (25 °C). Addition of aqueous dsDNA solution (1% (w/v)) to the above dispersion prepared with the protein concentration of Czein = 0.01-0.5% (w/v) caused a concomitant change in ethanol content from 14-35% (v/v), which in turn generated zein nanoparticles in situ of size 80-120 nm increasing with water content. The subsequent associative interaction between DNA (polyanion; 2000 bps) and the positively charged zein nanoparticles, (at pH = 4) was driven by Coulombic forces, and by the solvent hydrophobicity due to the ethanol content of the binary solvent...
August 18, 2017: Soft Matter
https://www.readbyqxmd.com/read/28819658/weld-formation-during-material-extrusion-additive-manufacturing
#5
Jonathan E Seppala, Seung Hoon Han, Kaitlyn E Hillgartner, Chelsea S Davis, Kalman B Migler
Material extrusion (ME) is a layer-by-layer additive manufacturing process that is now used in personal and commercial production where prototyping and customization are required. However, parts produced from ME frequently exhibit poor mechanical performance relative to those from traditional means; moreover, fundamental knowledge of the factors leading to development of inter-layer strength in this highly non-isothermal process is limited. In this work, we seek to understand the development of inter-layer weld strength from the perspective of polymer interdiffusion under conditions of rapidly changing mobility...
August 18, 2017: Soft Matter
https://www.readbyqxmd.com/read/28815232/blue-shifting-tuning-of-the-selective-reflection-of-polymer-stabilized-cholesteric-liquid-crystals
#6
Kyung Min Lee, Vincent P Tondiglia, Nicholas P Godman, Claire M Middleton, Timothy J White
We report on electrically-induced, large magnitude (>300 nm), and reversible tuning of the selective reflection in polymer stabilized cholesteric liquid crystals (PSCLCs) prepared from negative dielectric anisotropy nematic liquid crystal hosts. The electrically-induced blue shift in the selective reflection of the PSCLCs is distinguished from our prior reports of bandwidth broadening and red-shifting tuning of the selective reflection in PSCLCs. The dominant factor in delineating the electro-optic response of the PSCLCs detailed here are the preparation conditions...
August 17, 2017: Soft Matter
https://www.readbyqxmd.com/read/28815230/elastic-deformation-of-soft-coatings-due-to-lubrication-forces
#7
Yumo Wang, Matthew R Tan, Joelle Frechette
Elastic deformation of rigid materials with soft coatings (stratified materials) due to lubrication forces can alter the interpretation of dynamic surface forces measurements and prevent contact formation between approaching surfaces. Understanding the role of elastic deformation on the process of fluid drainage is necessary, in particular for the case where one (or both) of the interacting materials consists of a rigid substrate with a soft coating. We combine lubrication theory and solid linear elasticity to describe the dynamic of fluid drainage past a compliant stratified boundary...
August 17, 2017: Soft Matter
https://www.readbyqxmd.com/read/28815229/edge-mode-amplification-in-disordered-elastic-networks
#8
Le Yan, Jean-Philippe Bouchaud, Matthieu Wyart
Understanding how mechanical systems can be designed to efficiently transport elastic information is important in a variety of fields, including in materials science and biology. Recently, it has been discovered that certain crystalline lattices present "topologically-protected" edge modes that can amplify elastic signals. Several observations suggest that edge modes are important in disordered systems as well, an effect not well understood presently. Here we build a theory of edge modes in disordered isostatic materials and compute the distribution g(κ) of Lyapunov exponents κ characterizing how modes penetrate in the bulk, and find good agreement with numerical results...
August 17, 2017: Soft Matter
https://www.readbyqxmd.com/read/28815228/inertio-elastic-flow-instabilities-in-a-90%C3%A2-bent-microchannel
#9
Junghee Kim, Sun Ok Hong, Tae Soup Shim, Ju Min Kim
Biological samples having viscoelastic properties are frequently tested using microfluidic devices. In addition, viscoelastic fluids such as polymer solutions have been used as a suspending medium to spatially focus particles in microchannels. The occurrence of flow instability even at low Reynolds number is a unique property of viscoelastic fluids. In this study, we report the instability in viscoelastic flow for a channel having a 90° bent geometry, which is a characteristic of many microfluidic devices...
August 17, 2017: Soft Matter
https://www.readbyqxmd.com/read/28813063/tuning-mass-transport-in-magnetic-nanoparticle-filled-viscoelastic-hydrogels-using-low-frequency-rotating-magnetic-fields
#10
Shahab Boroun, Faïçal Larachi
This study investigates the response of magnetic nanoparticles (MNPs), dispersed in a viscoelastic hydrogel, to an external rotating magnetic field (RMF) for the purpose of developing a new class of magneto-responsive materials with tunable mass transport properties. Ferrogels were prepared by chemical cross-linking and polymerization of acrylamide in colloidal dispersions of thermally blocked MNPs of cobalt ferrite. Magnetization measurements of ferrogels in a swollen state revealed a transitional state from ferromagnetism to superparamagnetism through the shrinkage of hysteresis loops and the reduction of remanent magnetization...
August 16, 2017: Soft Matter
https://www.readbyqxmd.com/read/28812094/force-percolation-of-contractile-active-gels
#11
REVIEW
José Alvarado, Michael Sheinman, Abhinav Sharma, Fred C MacKintosh, Gijsje H Koenderink
Living systems provide a paradigmatic example of active soft matter. Cells and tissues comprise viscoelastic materials that exert forces and can actively change shape. This strikingly autonomous behavior is powered by the cytoskeleton, an active gel of semiflexible filaments, crosslinks, and molecular motors inside cells. Although individual motors are only a few nm in size and exert minute forces of a few pN, cells spatially integrate the activity of an ensemble of motors to produce larger contractile forces (∼nN and greater) on cellular, tissue, and organismal length scales...
August 16, 2017: Soft Matter
https://www.readbyqxmd.com/read/28812091/influence-of-surface-tension-in-the-surfactant-driven-fracture-of-closely-packed-particulate-monolayers
#12
Christian Peco, Wei Chen, Yingjie Liu, M M Bandi, John E Dolbow, Eliot Fried
A phase-field model is used to capture the surfactant-driven formation of fracture patterns in particulate monolayers. The model is intended for the regime of closely-packed systems in which the mechanical response of the monolayer can be approximated as that of a linearly elastic solid. The model approximates the loss in tensile strength of the monolayer with increasing surfactant concentration through the evolution of a damage field. Initial-boundary value problems are constructed and spatially discretized with finite element approximations to the displacement and surfactant damage fields...
August 16, 2017: Soft Matter
https://www.readbyqxmd.com/read/28812090/zero-charged-catanionic-lamellar-liquid-crystals-doped-with-fullerene-c60-for-potential-applications-in-tribology
#13
Mengjun Chen, Baoyong Liu, Xiaolin Wang, Yanxu Fu, Jingcheng Hao, Hongguang Li
The formation of lamellar liquid crystals (LLCs) has been demonstrated in a few salt-free catanionic surfactant systems and their properties have been well documented. However, examples of their combination with other materials are relatively rare. Herein, a salt-free zero-charged catanionic surfactant with low chain melting temperature was prepared by mixing equimolar tetradecyltrimethylammonium oxide (TTAOH) and oleic acid (OA) in water, and its concentration-dependent aggregate transition was investigated...
August 16, 2017: Soft Matter
https://www.readbyqxmd.com/read/28808713/a-smart-organic-gel-template-as-metal-cation-and-inorganic-anion-sensor
#14
Novina Malviya, Mriganka Das, Poulami Mandal, Suman Mukhopadhyay
A carboxamide based molecule has shown unique gelation property in an aqueous mixture of DMF or DMSO. The gel itself has shown aggregation-induced fluorescence enhanced emission (AIEE), which can be utilized effectively in sensing ferrous and ferric ions as both of them switch off the fluorescence completely. An investigation by IR spectroscopy reveals an enhanced π interaction of nitrile group with the iron center and this could be the possible reason behind the complete quenching of AIEE. This molecule was further investigated for the formation of metallogels for a wide array of cations, which in turn can act in tandem to behave as a dynamic array to detect several anions by either switching off or switching on the emission property of the metallogels...
August 15, 2017: Soft Matter
https://www.readbyqxmd.com/read/28805224/molecular-dynamics-based-strength-estimates-of-beta-solenoid-proteins
#15
Amanda Parker, Krishnakumar Ravikumar, Daniel Cox
The use of beta solenoid proteins as functionalizable, nanoscale, self-assembling molecular building blocks may have many applications, including templating the growth of wires or higher-dimensional structures. By understanding their mechanical strengths, we can efficiently design the proteins for specific functions. We present a study of the mechanical properties of seven beta solenoid proteins using GROMACS molecular dynamics software to produce force/torque-displacement data, implement umbrella sampling of bending/twisting trajectories, produce Potentials of Mean Force (PMFs), extract effective spring constants, and calculate rigidities for two bending and two twisting directions for each protein...
August 14, 2017: Soft Matter
https://www.readbyqxmd.com/read/28805220/revival-of-the-nearly-extinct-fluorescence-of-coumarin-6-in-water-and-complete-transfer-of-energy-to-rhodamine-123
#16
Rajashree Banerjee, Pradipta Purkayastha
The nearly extinct fluorescence of coumarin 6 in water due to microcrystal formation is revived by micelles. Practically complete transfer of energy from coumarin 6 to rhodamine 123 through resonance energy transfer could be achieved.
August 14, 2017: Soft Matter
https://www.readbyqxmd.com/read/28805217/mixed-emulsion-of-liquid-crystal-microresonators-towards-white-laser-systems
#17
Gia Petriashvili, Maria Penelope De Santo, Raul Josue Hernandez, Riccardo Barberi, Gabriella Cipparrone
Microdroplet systems have attracted great interest because of their wide range of applications, easiness in processing and handling, feasibility in developing miniaturized devices with high performances and large flexibility. In this study, a stable emulsion based on different dye-doped chiral liquid crystal droplets has been engineered in order to achieve simultaneous omnidirectional lasing at different wavelengths. To obtain the mixed emulsion of dye doped Bragg onion-type microresonators the twofold action, as a surfactant and a droplet stabilizer, of the polyvinyl alcohol dissolved in water has been exploited...
August 14, 2017: Soft Matter
https://www.readbyqxmd.com/read/28805212/heterogeneous-interface-adsorption-of-colloidal-particles
#18
Dong Woo Kang, Jin Hyun Lim, Bum Jun Park
The heterogeneous adsorption behaviors of charged colloidal particles to oil-water interfaces were quantitatively and statistically investigated. Using optical laser tweezers, the particles in a sessile water drop formed in an oil phase were laterally translated toward the slope of the oil-water interface and their attachment to the interface was attempted. The adsorption probability was found to logarithmically decrease as the ionic strength decreased and to depend on the holding time during which an optically trapped particle was held at the position closest to the interface...
August 14, 2017: Soft Matter
https://www.readbyqxmd.com/read/28804800/interfacial-rheological-properties-of-self-assembling-biopolymer-microcapsules
#19
Kaili Xie, Clément de Loubens, Frédéric Dubreuil, Deniz Z Gunes, Marc Jaeger, Marc Léonetti
Tuning the mechanical properties of microcapsules through a cost-efficient route of fabrication is still a challenge. The traditional method of layer-by-layer assembly of microcapsules allows building a tailored composite multi-layer membrane but is technically complex as it requires numerous steps. The objective of this article is to characterize the interfacial rheological properties of self-assembling biopolymer microcapsules that were obtained in one single facile step. This thorough study provides new insights into the mechanics of these weakly cohesive membranes...
August 14, 2017: Soft Matter
https://www.readbyqxmd.com/read/28798970/superhydrophobic-highly-adhesive-arrays-of-copper-hollow-spheres-produced-by-electro-colloidal-lithography
#20
Damien Bazin, Chrystel Faure
We report the patterning of copper surfaces which display both superhydrophobicity and high adhesion thanks to a new feature geometry, and without resorting to chemical modification. Polystyrene beads organized in 2D crystals under an AC electric field act as a template for the growth of copper deposited via cupric ion-loaded multi-lamellar vesicles. After the removal of the beads, hexagonal arrays of supported hollow spheres or copper bowls are generated, depending on the amount of deposited copper. While the bowl-covered surfaces display a predictable decreasing wettability (Cassie model) as their wall height increases, the hollow sphere-covered surfaces exhibit both high adhesion and superhydrophobicity (Cassie-Baxter state)...
August 11, 2017: Soft Matter
journal
journal
41529
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"