Yudu emulsion is a photosensitive liquid used in screen printing, specifically tailored for the Yudu personal screen printing machine. This emulsion is applied to a screen and then exposed to light with a design in place, hardening where the light hits and remaining soft where blocked by the design. After exposure, the soft areas can be washed out, leaving a stencil of the design on the screen through which ink can be pressed onto fabric or other surfaces. Yudu emulsion is part of a DIY kit aimed at artists and hobbyists, making screen printing accessible at home. Its ease of use and the creative potential it unlocks make it a popular choice for custom clothing, artwork, and personalized gifts.

Resin-coated proppant is a type of sand or ceramic material coated with a layer of resin used in the hydraulic fracturing process (fracking) to extract natural gas and oil. This coating enhances the proppant's strength and prevents the grains from clumping together, which helps keep the fractures in the rock open once the hydraulic pressure is relieved. The use of resin-coated proppant improves the productivity of a well by ensuring a more effective flow of hydrocarbons to the wellbore and reducing the amount of fine particles that can obstruct the flow. Additionally, it can offer better performance in downhole conditions compared to uncoated proppants due to its enhanced conductivity and improved crush resistance. Choosing the right type of resin-coated proppant can significantly affect the efficiency and lifespan of the well.

To make iron oxide (Fe2O3), a common method involves the oxidation of iron in the presence of oxygen and water. Start by taking fine steel wool or iron filings and place them in a bowl. Add a little water to just moisten the iron - this accelerates the oxidation process. For a faster reaction, add salt to the water, which acts as a catalyst. Expose the moistened iron to air, preferably in a warm environment to speed up the reaction. Over days or weeks, depending on conditions and the amount of catalyst used, the iron will oxidize, forming rust or iron oxide. To ensure a thorough conversion, occasionally stir the mixture to expose any unreacted iron to the environment. Once the process is complete, dry the resultant iron oxide for storage or usage in experiments, such as in thermite reactions or as pigments.