Self-reporting and self-regulating liquid crystals

Kim, Young-Ki
Wang, Xiaoguang
Mondkar, Pranati
Büküşoğlu, Emre
Abbott, Nicholas L.
Liquid crystals (LCs) are anisotropic fluids that combine the long-range order of crystals with the mobility of liquids(1,2). This combination of properties has been widely used to create reconfigurable materials that optically report information about their environment, such as changes in electric fields (smart-phone displays)(3), temperature (thermometers)(4) or mechanical shear(5), and the arrival of chemical and biological stimuli (sensors)(6,7). An unmet need exists, however, for responsive materials that not only report their environment but also transform it through self-regulated chemical interactions. Here we show that a range of stimuli can trigger pulsatile (transient) or continuous release of microcargo (aqueous microdroplets or solid microparticles and their chemical contents) that is trapped initially within LCs. The resulting LC materials self-report and self-regulate their chemical response to targeted physical, chemical and biological events in ways that can be preprogrammed through an interplay of elastic, electrical double-layer, buoyant and shear forces in diverse geometries (such as wells, films and emulsion droplets). These LC materials can carry out complex functions that go beyond the capabilities of conventional materials used for controlled microcargo release, such as optically reporting a stimulus (for example, mechanical shear stresses generated by motile bacteria) and then responding in a self-regulated manner via a feedback loop (for example, to release the minimum amount of biocidal agent required to cause bacterial cell death).


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Dericioğlu, Arcan Fehmi (2001-12-01)
The idea of increasing the fracture resistance of optically transparent Ceramics by incorporation of continuous fibers with a small expense in their light transmission was applied to a SiC (SCS-6) fiber-reinforced magnesium aluminate spinel matrix composite. It was found that although there is a slight decrease in the light transmittance of the transparent monolithic matrix with increasing fiber volume fraction, a fail-safe mechanism appeared in the composite by the bridging effect of the intact fibers
Nanoparticle self-assembly at the interface of liquid crystal droplets
Rahimi, Mohammad; Roberts, Tyler F; Armas-Pérez, Julio C; Wang, Xiaoguang; Büküşoğlu, Emre; Abbott, Nicholas L; de Pablo, Juan Jose (Proceedings of the National Academy of Sciences, 2015-04-28)
Nanoparticles adsorbed at the interface of nematic liquid crystals are known to form ordered structures whose morphology depends on the orientation of the underlying nematic field. The origin of such structures is believed to result from an interplay between the liquid crystal orientation at the particles' surface, the orientation at the liquid crystal's air interface, and the bulk elasticity of the underlying liquid crystal. In this work, we consider nanoparticle assembly at the interface of nematic drople...
Application of Electric Resistance Heating Method on Titanium Hot Forming at Industrial Scale
Ozturk, Fahrettin; Ece, Remzi Ecmel; Polat, Naki; Koksal, Arif; Evis, Zafer; Sheikh-Ahmad, Jamal Y. (Springer Science and Business Media LLC, 2016-11-01)
In this study, hot forming of DIN WL 3.7024 commercially pure titanium with a sheet thickness of 0.6 mm was performed by electric resistance heating. The sheet materials were heated at 600, 650, and 680 A degrees C and then hot formed with an industrial press. Grain size measurement and XRD analysis were performed for each forming temperature in order to investigate microstructure and phase changes. Results indicate that no microstructural changes have occurred at the mentioned temperature range. It was con...
Numerical and Experimental Investigation into LWIR Transmission Performance of Complementary Silicon Subwavelength Antireflection Grating (SWARG) Structures
Cetin, Ramazan; Akın, Tayfun (Springer Science and Business Media LLC, 2019-03-18)
This paper presents a detailed comparison between the long wave infrared (LWIR) transmission performances of binary, silicon based, structurally complementary pillar and groove type antireflective gratings that can be used for wafer level vacuum packaging (WLVP) of uncooled microbolometer detectors. Both pillar and groove type gratings are designed with various topological configurations changing in various period sizes (Delta) from 1.0 mu m to 2.0 mu m, various heights/depths (h) from 0.8 mu m to 1.8 mu m,...
alpha ' formation kinetics and radiation induced segregation in neutron irradiated 14YWT nanostructured ferritic alloys
Aydoğan Güngör, Eda; March, K.; El-Atwani, O.; Krumwiede, D. L.; Hosemann, P.; Saleh, T.; Maloy, S. A. (Springer Science and Business Media LLC, 2019-06-01)
Nanostructured ferritic alloys are considered as candidates for structural components in advanced nuclear reactors due to a high density of nano-oxides (NOs) and ultrafine grain sizes. However, bimodal grain size distribution results in inhomogeneous NO distribution, or vice versa. Here, we report that density of NOs in small grains (2 mu m) before and after irradiation. After 6 dpa neutron irradiation at 385-430 degrees C, alpha' precipitation has been observed in these alloys; however, their size and numb...
Citation Formats
Y.-K. Kim, X. Wang, P. Mondkar, E. Büküşoğlu, and N. L. Abbott, “Self-reporting and self-regulating liquid crystals,” NATURE, pp. 539–560, 2018, Accessed: 00, 2020. [Online]. Available: