Lithium-sulfur (Li-S) battery research has been greatly advanced through designing sulfur host materials. Such information is useful in the formulation of products and the design of processes involving xanthan gum and related polysaccharide polymers. Effects on xanthan gum aqueous solutions of pH, electrolytes, changes in temperature, and added natural polysaccharides or synthetic polymers are highlighted. This review presents fundamental information on the behavior of xanthan gum in aqueous media, at conditions and in the presence of additives which are of interest to applications that benefit from viscosity changes such as in oil and gas extraction. In water, xanthan gum undergoes conformational transitions from helix to random coil, in response to stimuli such as pH, ionic strength, temperature, and shear. The performance of xanthan gum is based on its macromolecular conformation and association in solution and at interfaces. Xanthan gum is used as a thickening, stabilizing, or suspending agent in various applications, e.g., food, pharmaceutical, cosmetic, and petroleum extraction. The terminal mannose residues also carry acetate groups. Ketal bonds link pyruvic acid residues to approximately half of the terminal mannose residues. The trisaccharide β-d-mannose-(1–4)-α-d-glucuronic acid-(1–2)-α-d-mannose is linked to O(3) position of every other glucose residue. The xanthan gum backbone consists of β-d-glucose linked like in cellulose. Xanthan gum is a naturally occurring polysaccharide obtained from Xanthomonas campestris. Based on our results, agar is the most suitable thickening/gelling agent from the viewpoint of storage stability. Neutral electrolyzed water-based gels might be useful to remove oral microbes. The gel prepared with xanthan gum remarkably reduced its available chlorine concentration even under shaded and refrigerated storage conditions, failing to maintain its microbicidal effect following 1-day storage, whereas other gels, prepared with carboxyvinyl polymer or agar, maintained effective concentration (>20 ppm), with high microbicidal effects following 9-day and 21-day storage, respectively. Immediately after preparation, all gels (70 ppm) could completely remove microbes by a 3-min treatment. We evaluated their microbicidal effects against four strains and storage stabilities indicated by available chlorine concentration. For wider use, three neutral electrolyzed water-based gels, namely, HOCl-containing aqueous gels were prepared with a thickening/gelling agent in this study. These results demonstrate the great potential of these materials for the replacement of conventional plastics.Įlectrolyzed waters, containing mainly hypochlorous acid, are used in dental practice because of their high microbicidal effect. Moreover, tensile strength was enhanced at pH 9, probably due to bonding promotion at alkaline conditions. Thus, extrusion resulted in a greater gluten-plasticizer compatibility compared to compression, as denoted the temperature ramp tests, especially in the presence of additives (ie. These bioplastics were characterized by the measurement of their mechanical properties and their water uptake capacity, proving that the modification of bioplastics cause variations in their properties. In this way, the preparation of wheat gluten bioplastics by extrusion was the main objective of this research, modifying their structure by varying the pH value or by incorporating additives (glyoxal or xanthan gum). For this reason, their manufacture using the traditional techniques used for the production of plastics, such as extrusion, would help transferring bioplastics production to an industrial scale. The readings obtained do not directly correspond with any other viscosity scale.Recently, bioplastic have generated an increasing interest as an alternative to conventional plastics. The instrument used throughout the industry since 1934 is called a Viscosity Cup or Stein-Hall Cup. Record the time and temperature of adhesive.The time in seconds is the Stein-Hall viscosity.Fill the viscosity cup with strained adhesive and with a stopwatch measure the time it takes for the level in the cup to drop from the upper pin to the lower pin.Continue until the time is 15 seconds (+/- 1 second). If it is shorter than that, bend the pins apart and check the calibration again. If it is longer than that, bend the pins together and check the calibration again. The time should be 15 seconds (+/- 1 second).Remove your finger and, with a stopwatch, measure the time it takes for the level in the cup to drop from the upper pin to the lower pin.Place finger over the orifice of the viscosity cup.Check the orifice to make sure it is not plugged, corroded or worn. The Stein hall cup must be calibrated before performing the test.
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