Throughout the mixing process, the clear red solution slowly changes to a denser red solution (Appendix figure 23). A thermometer was used for temperature checking. The beaker was removed from the hot plate when the temperature was found to be higher than 50 ℃. This was done to prevent a sudden gelation happen before all the active dissolved in the ethylene glycol. Moderate heating of the solution for a period of time is allowed to obtain a wet gel (Appendix figure 24).
The temperature of the melt was raised to 185 °C and the melt was kept on stirring for 10 minutes. Subsequently, the alloy was cast into copper mold. To homogenize the alloys, the ingots were cold rolled to >90% reduction in thickness and re-melted at 180 °C for 10 minutes and cast into copper mold. Finally, the ingots were again cold rolled to >70% reduction in thickness and preserved for subsequent characterization and
The solution was stirred at room temperature for 8h. The solvent was blown out with nitrogen. The residue was added to 1 ml of water containing 0.1% TFA and purified on RP-HPLC. Massspec of the final product clearly indicates presence of RB modified on PEI by series of peaks matching different polymer compositions (see Fig. 6).
Heat the solution until it is at 100 ˚C then continue heating for 75 minutes. Evolution of CO2 and NH3 is observed during heating. e. After 75 minutes of heating, stop stirring. Draw a little clear solution with a pipette, cool the solution to room temperature and measure its pH value with pH paper. when the pH is 7, allow the solution to cool to room temperature.
. Before solution application, the HPTLC plates were sprayed with 10% (w/v) disodium ethylene diaminetetraacetic acid (Na2EDTA) solution in which the pH had been adjusted to 4 using glacial acetic acid. This Na2EDTA solution helps to avoid binding of the tetracyclines with trace metals in the adsorbents used . Since OTC and TC have similar chemical and physicochemical properties they form chelate complexes with metal ions and bind with proteins and silanol groups in the stationary phase. These undesirable properties have been controlled by the use of EDTA for plate treatment .
Titanium and its alloys react with interstitial elements such as oxygen, nitrogen, and hydrogen, below their respective melting points. In its reactions with other elements, titanium may form solid solutions and compounds with metallic, covalent or ionic bonding. Major alloying elements, added to improve mechanical properties and corrosion resistance, are classified as α-stabilizer, or β-stabilizers.The alloying elements are generally classified into three categories as α-stabilizer, β-stabilizer and neutral. The α-stabilizing elements extend the α phase field to higher temperatures, while β-stabilizing elements shift the β phase field to lower temperatures.
Week 1 a simple condensation reaction between benzaldeyde and hydroxylamine produced the product benzaldehyde oxime that was found to be in oil. The percentage yield of the experiment is 64%. The 36% loss can be due to the solution needing to be neutralised with glacial acid, there was no way to tell if the reaction was neutralised, to help increase yield the use of pH indictor paper to indicate whether the reaction was neutralised. As by using a rotary evaporator to remove the organic solvent may have caused small amounts of the product to evaporate off as it a low melting point solid, if the water bath temperature was too high would have caused to melt and evaporate off. As melting point was not measured was unable to tell whether the product is pure.
After dropped completely the copper manganese solution into the precipitant ageing for 2h, then filtered, washing several times with hot deionized water. After washing drying the precursor in an oven and calcination it in flowing air calcination conditions before measuring of the catalyst activity test. The amount of copper was added varied to the preparation of CuMnOx catalysts with nominal Cu/Mn molar ratios. After drying of the precursors their granules were crushed into powdered form for activity measurement purposes. 2.2 Characterization of catalysts The Scanning electron micrographs (SEM-EDX) produced the high-resolution image of a catalyst by an electron beam and the
In a typical procedure, TiO2 nanoparticles (TNP, 3.6 g) with pure anatase was added into a NaOH (10 N, 150 mL) solution in a teflon lined stainless steel autoclave, sonicated (2 min) and heated the autoclave at 403 K for 48 h in an oil bath under autogenesis pressure with stirring (250 rpm). After 48 h, the autoclave was cooled down to room temperature, subsequently the formed nanotube was washed with ultrapure water until the pH of the solution was >7. Afterward the nanotubes were washed with HCl (0.1 M) solution for overnight under stirring at room temperature. Then the nanotubes were filtered (Millipore filtration assembly) under vacuum pump and repeatedly washed with ultrapure water until the filtrate was free from chloride ion, which was checked by the addition of silver nitrate to the filtrate. Finally, the obtained nanotubes were dried in an oven at 343 K for 12 h and calcined in a muffle furnace at 773 K for 4 h. The synthesized nanotube was abbreviated as
This solution reaction is exothermic; because temperature was increased meaning heat was released. In the last part of the experiment, neutralization reaction was investigated. NaOH(aq) + HCl(aq) NaCl(aq) + H2O(l) Enthalpy change for neutralization reaction between HCl and NaOH were calculated to be -51kJ. For reactions involving strong acids and alkalis, like HCl and NaOH, the values are always very closely similar, with values between -57 and -58 kJ.2 The actual value of enthalpy change of neutralization reaction is equal to -57.9 kJ.2 The reason for dissimilarity of results could be loss of heat during the transferring of the NaOH to the HCl. Since, temperature was increased, the reaction is exothermic, heat was