Application of Magneto-optical Characteristic in Liquid: Verdet Constant as Quality Indicator of Repeatedly Cooking Oil

The Faraday Effect is a magnetooptical phenomenon in physics describing the interaction of light and magnetic fields in a medium. A parameter that indicates the interaction is the Verdet constant. In this research, Verdet constant was measured on cooking oil that has been used several times. Magneto-optical properties were measured using the polarimetry method, which uses a He-Ne Laser beam with a magnetic field treatment of 50 gauss, 80 gauss and 100 gauss. The samples analyzed were bulk and non-bulk cooking oil. Repeated use of cooking oil causes a change in the polarization axis of the polarized laser. This has an impact on the Verdet constant of the material. The difference in the Verdet constant shows that the Verdet constant can be used as an indicator of cooking oil that has been used up to three times.

Biomimetic Slippery PDMS Film with Papillae-Like Microstructures for Antifogging and Self-Cleaning

Transparent materials with antifogging and self-cleaning ability are of extreme significance for utilization in outdoor solar cell devices to alleviate the performance loss and maintenance costs. Herein, with inspiration from the anti-wetting surfaces in nature, regular papillae-like microstructure arrays (PMAs) inspired by lotus leaves were designed via a common UV lithography combined with a soft replication. Subsequently, the biomimetic slippery polydimethylsiloxane (PDMS) film (BSPF) inspired by the pitcher plant was fabricated successfully by infusing with hydrophobic liquid lubricant. The resultant surface has hydrophobic surface chemistry, a slippery interface, PMAs structure. The wettability, optical characteristic, antifogging property and self-cleaning ability of the PMAs-based BSPF were characterized experimentally. The film displays excellent optical transmittance, antireflection, antifogging, and self-cleaning properties, which is superior to the flat PDMS film (FPF). Remarkably, an average reflection of ∼11.3% in the FPF was reduced to ∼8.9% of the BSPF. In addition, after gradient spray test for 120 s, the antifogging efficiency was close to 100% for the BSPF surface in comparison with the flat PDMS film (FPF), biomimetic PDMS film (BPF) and flat slippery PDMS film (FSPF) (35%, 70% and 85%). Furthermore, we also discovered that the BSPF surface exhibited a better self-cleaning performance toward a variety of liquids than solid dust.