We present a security device that can detect and block hacking using the characteristics of liquid crystals. This device is based on a liquid crystal cell consisting of a uniformly aligned layer and a photo-alignment layer. To inscribe a pattern, the device is illuminated when the liquid crystal is in the smectic phase. The resulting image is invisible after light irradiation. Heating to the nematic phase improves this alignment and reveals the recorded pattern. Returning to the smectic phase distorts the pattern. Because the pattern is not shown without heating and the trace of the pattern does not disappear once viewed, it is possible to detect whether data has been hacked. The device is easy to fabricate, cost-effective, and sensitive to outside intrusion.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1364/OE.441941 | DOI Listing |
Small Methods
December 2024
Institute of Translational Medicine, Nanjing Drum Tower Hospital, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, China.
Colored contact lenses have gained popularity among young individuals owing to their ability to alter the appearance of the wearer's eyes. However, conventional lenses containing chemical dyes are susceptible to detachment of the pigment layer, which can lead to corneal damage. In this research, a novel cellulose-based structural color contact lens (SCCL) is presented that enhances aesthetic appeal via a cholesteric liquid crystal (CLC) layer.
View Article and Find Full Text PDFJ Colloid Interface Sci
December 2024
Institute for Frontier Materials, Deakin University, Geelong VIC 3216, Australia. Electronic address:
Hypothesis: Optimizing interfacial positioning of crosslinkers within a reactive self-assembled hexagonal lyotropic liquid crystals (HLLC) system could assist in retaining the hexagonal structure during polymerization and thereby improving water filtration performances of the as-synthesized nanofiltration membranes.
Experiments: The positioning of the hydrophilic crosslinker, poly (ethylene glycol) diacrylate (PEGDA), within the reactive HLLC system was systematically investigated using H and C solid nuclear magnetic resonance (NMR) and small angle X-ray scattering (SAXS) techniques. The structural variation and water filtration performances of these HLLC systems with/without crosslinkers after polymerization were further studied using grazing incidence SAXS (GISAXS) and crossflow filtration tests, respectively.
ACS Appl Mater Interfaces
December 2024
Department of Applied Physics, Hebei University of Technology, Tianjin 300401, PR China.
Actuators based on liquid crystals have garnered significant attention due to their potential applications in wearable technology and bionic soft robots. Composite films composed of liquid crystal polymer networks (LCNs) and other stimulus-responsive materials exhibit the capability to convert external stimuli into mechanical deformation. However, the development of sunlight-driven actuators presents significant challenges, primarily due to the relatively low intensity of sunlight and the limited conversion efficiency of photothermal materials.
View Article and Find Full Text PDFAdv Mater
December 2024
Extreme Materials Research Center, Korea Institute of Science and Technology, 5, Hwarang-ro 14-gil, Seoul, Seongbuk-gu, 02792, Republic of Korea.
Additive manufacturing has sought active and interactive means of creating predictable structures with diverse materials. Compared to such active manufacturing tools, current crystallization strategies remain in statistical and passive programs of crystals via macroscale thermodynamic controllers, commonly lacking active means to intervene in crystal growth in a spatiotemporal manner. Herein, a strategy toward active and interactive programming and reprogramming of crystals, realized by real-time tangible feedback on growing crystals by delicately controlling the degree of in-situ, localized photopolymerization of polymeric structures via additive manufacturing is presented.
View Article and Find Full Text PDFJ Am Chem Soc
December 2024
College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.
Two-dimensional (2D) high-entropy transition metal dichalcogenides (HETMDs) have gained significant interest due to their structural properties and correlated possibilities for high-end devices. However, the controlled synthesis of 2D HETMDs presents substantial challenges owing to the distinction in the inherent characteristics among diverse metal elements in the synthesis, such as saturated vapor pressure of precursors and formation energy of products. Here, we present the synthesis of a 2D HETMD single crystal with 0.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!