Guar gum improved electrolyte compatibility. These changes in properties result in increased use in different fields, like textile printing, explosives, and oil-water fracturing applications. Guar molecules have a tendency to aggregate during the hydraulic fracturing process, mainly due to intermolecular hydrogen bonding. These aggregates are detrimental to oil recovery because they clog the fractures, restricting the flow of oil. Cross-linking guar polymer chains prevents aggregation by forming metal – hydroxyl complexes. The first crosslinked guar gels were developed in the late ‘60’s. Several metal additives have been used for crosslinking, among them are chromium, aluminum, antimony, zirconium, and the more commonly used,
Gel doc Gel doc A gel doc, also known as a gel documentation system, gel image system or gel imager, refers to equipment widely used in molecular biology laboratories for the imaging and documentation of nucleic acid and protein suspended within polyacrylamide or agarose gels. These gels are typically stained with ethidium bromide or other fluorophores such as SYBR Green. Generally, a gel doc includes an ultraviolet (UV) light transilluminator, a hood or a darkroom to shield external light sources and protect the user from UV exposure, and a CCD or CMOS camera for image capturing. The main manufacturers of Gel documentation