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Build a Milk Quality Testing Device
Published in Anudeep Juluru, Shriram K. Vasudevan, T. S. Murugesh, fied!, 2023
Anudeep Juluru, Shriram K. Vasudevan, T. S. Murugesh
In chemistry, pH (potential of hydrogen or power of hydrogen) is a logarithmic scale used to specify the acidity or basicity of an aqueous solution. A solution that has the solvent as water is known as an aqueous solution. The pH scale is inversely proportional to the molar concentration of hydrogen ions (H+) in the solution: pH=−log10[H+]
Synthesis of Polymer-Based Composites for Application in Field-Effect Transistors
Published in Suman Lata Tripathi, Sobhit Saxena, Sushanta Kumar Mohapatra, Advanced VLSI Design and Testability Issues, 2020
Amit Sachdeva, Pramod K. Singh
When we talk about composites, one of the main applications of polymer-based composites is in the form of electrolytes. Before discussing about polymer electrolytes, one must be clear with the term electrolyte. Electrolytes are defined as materials that conduct electricity either in their molten state or in the form of aqueous solution [4]. Generally, electrolytes are formed when a salt is dissolved in a polar solvent such as water. On dissolving in polar solvent, the salt gets dissociated into respective positively and negatively charged ions, which are responsible for its conduction. Such materials that conduct via movement of ions are known as ionic conductors.
Solutions
Published in W. John Rankin, Chemical Thermodynamics, 2019
In aqueous solutions the solvent is water. These are the most familiar type of solution. For aqueous solutions of soluble organic compounds (for example sucrose, glucose, ethanol) and simple inorganic gases such as oxygen and nitrogen, the solute is present in the solvent as molecules. The large majority of inorganic substances, however, dissociate to varying extents into ions when dissolved in water. These substances are referred to as electrolytes when they are dissolved in water. The thermodynamics of electrolytes and electrolyte solutions is discussed in detail in Chapter 12. For thermodynamic purposes, the concentration of solutes and ions in dilute aqueous solutions is usually expressed in terms of molality (Equation 2.6).
Synthesis of carboxymethyl Xanthan/ double-walled carbon nanotube hybrid hydrogel nanocomposite for transdermal release of drug
Published in Soft Materials, 2022
Maroua Stasaid, Khalida Boutemak, Lahcene Ibtissem, Emmanuel Flahaut, Amel Hadj-Ziane- Zafour
In order to evaluate the potential in vitro release of CNTs from the anti-inflammatory patch under extreme conditions, a medium simulating human sweat was prepared. The aqueous solution of artificial sweat was composed of 0.5% sodium chloride, 0.1% lactic acid, and 0.1% urea, and the pH was adjusted to 6.5 by adding ammonia.[44] The contact surface with the outside was measured for each tested sample, which was inserted into a vial containing artificial sweat. Thereafter, sealed vials were placed in an oven at different temperatures (37°C, 40°C, and 50°C) for 24 hours. After cooling to room temperature, the artificial sweat solution was recovered using a Pasteur pipette and deposited onto a cellulose nitrate membrane (0.45 μm) filter for immediate vacuum filtration. To remove the salts present on the surface of the membrane, rinsing with 20 ml of deionized water was performed. The membrane was recovered and then dried before Raman analysis.
Stability of nanoparticle stabilized oil-in-water Pickering emulsion under high pressure and high temperature conditions: comparison with surfactant stabilized oil-in-water emulsion
Published in Journal of Dispersion Science and Technology, 2021
Ganesh Kumar, Abhijit Kakati, Ethayaraja Mani, Jitendra S. Sangwai
In this study, two types of emulsion systems are explored to measure its stability under HPHT conditions. The first type of emulsion was stabilized by positively charged Ludox CL silica nanoparticle (2 wt%) and sodium chloride (NaCl) salt (2 M) of the aqueous solution. The second type of emulsion was stabilized by using anionic surfactant sodium dodecyl sulfate (SDS) slightly above the critical micelle concentration (CMC) value (CMC + 20% CMC), 9.84 mM. The CMC of SDS surfactant in water was found to be 8.2 mM at 25 °C. An equal volume (12 mL) of oil phase (n-decane) and (12 mL) of aqueous phase containing either surfactant (CMC + 20% CMC) or nanoparticle (Ludox CL silica nanoparticle (2 wt%) and NaCl salt (2 M)) were emulsified in a glass vial (30 mL) having screw cap using an IKA T 25 digital Ultra-Turrax homogenizer at a speed of 13,000 rpm for 3 minutes at ambient temperature (298 ± 2 K). The T 25 digital Ultra-Turrax homogenizer contains dispersion element of stator diameter of 18 mm, rotor diameter of 12.7 mm, the gap between the stator and diameter of 0.3 mm, and immersion depth of 40–165 mm.
Synthesis and characterization of a PAMAM dendrimer nanocarrier functionalized by HA for targeted gene delivery systems and evaluation in vitro
Published in Journal of Biomaterials Science, Polymer Edition, 2021
Haimei Hu, Han Wang, Shuanghong Liang, Xiaoling Li, Dan Wang
Polymers were synthesized in sodium tetraborate aqueous solution of sodium chloride. Briefly, PAMAM G4 (0.043 g) was dissolved in 50 mL of solution containing 0.1 M sodium tetraborate and 0.4 M sodium chloride and stirred until completely dissolved, then HA3850 (0.0385 g) was added and stirred at 40 °C until the HA was completely dissolved and to the aqueous solution added NaBH3CN (0.0067 g). Finally, the reaction was further stirred at 40 °C for three days, then dialyzed against sodium chloride solution for 1 day and double distilled water for 2 days to remove the unreacted monomers. After three days, the dialysis bag liquid was divided into vials and frozen in the refrigerator at –20 °C. Finally, the PAMAM G4-HA3850-5% was obtained by lyophilization. We used the same method to obtain the following compound: PAMAM G4-HA3850-15%, PAMAM G4-HA3850-25%, PAMAM G4-HA17200-5% and PAMAM G5-HA3850-5%, PAMAM G5 -HA3850-15%, PAMAM G5 -HA3850-25%, PAMAM G5-HA17200-5% and so on. The synthesis route is shown in Figure 1.