temperatures: for example, viscosity is reduced. Xanthan gum provides the same thickening, stabilizing, and suspending properties during long-term storage at elevated temperatures as it does at ambient conditions. In addition, it ensures excellent freeze–thaw stability. Solutions are also stable in ...
Xanthan gum was dissolved with BMIMCl [2% (w/w)] and the reaction was carried out in the presence of acetic anhydride (five equiv. for hydroxy groups in a repeating unit) with stirring the solution at elevated temperatures. The structures of xanthan gum acetates were confirmed by the 1 H...
Elevated temperatures and reduced ionic concentrations within the solution tend to favor the disordered coil conformation (Fig. 1b). For example, the transition can exhibit a midpoint temperature of 40–50 °C (Chantaro et al., 2013). It is important to note that the midpoint temperature ...
determined that the stability of clayey sand (80 % sand, 20 % clay) necessitated 3 % cement to improve compressive and shear strength [72], whereas our work indicated 0.25 % xanthan gum as the ideal quantity for comparable soil stabilization. Stabilizing one ton of soil economically necessitate...
Elevated levels of ROS can adversely affect cell membrane stability, triggering lipid peroxidation and generating the cytotoxic metabolite MDA [60]. Suppression of increased ROS production becomes crucial for curtailing lipid peroxidation, pre- venting the disruption of dynamic equilibrium and subse- quent...
long-term storage at elevated temperature as it does at ambient conditions. In addition, it imparts excellent freeze/thaw stability to most compositions. Table 1: Effect of Temperature on Solution Viscosity EFFECT of pH VANZAN xanthan gum is recommended for use in both acidic and alkaline systems...
As an EOR fluid, xanthan gums are well known for their excellent rheological properties, such as high viscosity even at low concentrations, stability in acid and alkaline solutions, compatibility with most metal salts, excellent solubility, and resistance to degradation both at elevated temperatures [...
(large volume) heat exchangers. The use of large volume heat exchangers cause the xanthan solutions to remain at elevated temperatures long enough for thermal degradation of the polymer to begin, thus reducing the maximum viscosity achievable. In addition, the large mass of fluid and metal present...
The ability of the acidic treatment fluids of the present invention to maintain a degree of viscosity at such elevated temperatures may be affected by the time a particular fluid is exposed to such temperatures. For example, in some fracture acidizing applications, there may be a considerable ...
At higher temperatures, and in the presence of pressure, the viscosity is typically reduced within about 2 days, indicating increased enzyme activity and increased enzyme complex stability. The fermentation is