There exist visual signs that have stood their ground throughout the ages for the simple reason that they fit the bill. They are evident or evidently true representations. The bill they fit are life, sentience, and sapience. Which is saying that it comes down to instinctive recognition, i.e., unexplainable, but unmistakably evident. They are true because we feel they are true. This paper attempts to counter the adage that “the obvious can only be explained to those that already understand it” by visually transforming the ancient sign best known as the “yin-yang sign” or Taijitu. The goal is to demonstrate that diagrammatical transformations reveal knowledge inherently present in the visual. In other words, an attempt to reinstate the status of diagram that the Taijitu originally had instead of an image, a visual, an emblem … labels that point more to what it demonstrates than to what it is, i.e., an actionable tool. To do so C. S. Peirce’s triadic sign will be juxtaposed to the sign under analysis, and his work on Existential Graphs will be used to orchestrate transformations, thus tapping into the diagrammatic nature of the sign. Following which, the similarities with Henri Lefebvre’s trialectics will be shown in the resulting diagrammatic transformations.
We describe a very simple, two-step synthetic method to prepare gold nanorods with extremely high aspect ratios (> 20) and average lengths of more than 1000 nm. The method is based on a seed-mediated growth in presence of the surfactant cetyltrimethylammonium bromide. The length and aspect ratios of the nanorods can be manipulated by varying the surfactant concentration.
In nature, several plants and insects, such as the Rosa montana petals or the gecko foot, are highly hydrophobic but with an extremely high water adhesion. These properties are called parahydrophobic. Here, in order to reproduce such properties we have developed original 3,4-ethylenedioxypyrrole monomers containing branched alkyl chains in order to have intrinsically hydrophilic polymers. In certain conditions, the electrodeposited conducting polymer films are parahydrophobic due to the presence fibrous structures forming large agglomerates. On such surfaces, a water droplet deposited on them remains stuck even after a substrate inclination of 180°. Such properties are extremely interesting for applications in water harvesting, for example.
Vegetal and animal reigns offer many examples of surfaces with surprising and interesting wetting properties. As example, springtails present superoleophobic properties allowing to live in soil and Lotus leaves show self-cleaning ability even under rainfalls. Indeed, it is known that self-cleaning properties can help to remove dust and particles during rainfalls and as a consequence to clean the surface. The bioinspiration of these surface properties is of a real interest for industrial applications in the nanotechnology field such as photovoltaic systems or anti corrosive material. Here, we use a strategy based on electropolymerization to obtain these properties. The Staudinger-Vilarrasa reaction is used to prepare innovative 3,4-ethylenedioxypyrrole (EDOP) monomers with fluorinated chains. Using C6F13 or C8F17 chains, the polymer surfaces formed after electrodeposition show superhydrophobic and superoleophobic features. Here we study the surface wettability depending on the surface energy (based on the perfluorinated chain length), the surface roughness and morphology.