In precipitation process, large volumes of sludge are generated which can present dewatering and disposal problems , as well as re-carbonation of the softened water are needed . Ion-exchange resin have been widely used to remove calcium and magnesium ions due to their many advantages, such as high capacity and fast kinetics [12-14]. However, ion-exchange resins must be regenerated by chemical reagents when they are saturated and the regeneration can cause serious secondary pollution. In large scale, application of resin is expensive . In recent years, various method such as nanofiltration [15, 16], capacitive deionization , electrodialysis , electrochemical treatment  and, adsorption [20, 21] have been widely studied for ions removal from aqueous solution, especially water softening.
4- Set up reflux system using a clean and dry condenser . 5- Place the flask on the hot plate and heat the reaction for 45 minutes - 1 hour . 6- When the reflux is over , remove magnetic stirrer and allow the reaction to cool to room temperature . 7- Add 20 ml of ice water to a separating funnel
Measure and record the total mass of water and the beaker. Subtract this with the value from step 2 in order to achieve the initial mass of water. Using the electronic scale, Measure and record the mass(g) of the alcohol burner, continue by measuring 150 g of ethanol and insert it into the alcohol burner. Place the wire gauze on top of ring clamp belonging to the ring stand. Place the 250ml beaker on top of the wire gauze.
DMF was used as a solvent and AIBN (0.5% w/w of total monomer) as free radical initiator .The reaction was carried out at 70±2° C for 6 hour with constant stirring. After completion of the process it was cooled to room temperature and resultant polymer solution was poured in the large amount of methanol with stirring when polymer precipitated out. It was filtered and washed with methanol. The polymer was purified by repeated precipitation using methanol from solution in DMF and then it dried. 2.3 Preparation of PS
In the round-bottom flask (100 mL), we placed p-aminobenzoic acid (1.2 g) and ethanol (12 mL). We swirled the mixture until the solid dissolved completely. We used Pasteur pipet to add concentrated sulfuric acid (1.0 mL) to the flask. We added boiling stone and assembled the reflux. Then, we did reflux for 75 minutes.
Before moving on to the formation of gel process, the magnetic bars were removed from all the samples. Continuous heating at high temperature (more than 50℃ but lower than 80℃) was allowed to obtain wet gel for all the samples of Co-Ti substitution from 0.2 to 1.0. After the wet gel was formed, continuous heating of the wet gel yield the product in powder
The mixture was finally made upto 5 mL with distilled water and placed in hot water bath at 95ºC for 1 h. After cooling, 1 mL of distilled water and 5 mL of the mixture of n-butanol and pyridine (15:1, v/v) was added. The mixture was vortexed and after centrifugation at 4000 rpm for 10 minutes, the absorbance of the organic layer (upper layer) was measured in UV-Vis spectrophotometer (Shimatzu) at 532 nm against blank using distilled water. TBA when allowed to react with MDA aerobically formed a colored complex [MDA-(TBA) 2 complex] which was measured with spectrophotometer. MDA concentration (measured as TBARS) was calculated as
Lecturer Date Introduction Theoretical Background Procedure The procedure was segmented into two categories, the reaction set up and the crude product isolation. Reaction set up The magnetic stirrer was prepared through placing it in the fume cupboard. 1 mmol of L-Phenylalanine was placed and weighed in a 5 mL conical vial. After that, a spin vane was inserted into the vial while adding 0.75 mL of 1M H2SO4 solution. During the addition of the sulphuric acid, the solution was stirred at room temperature until the amino acid (L-Phe) completely dissolved.
Acetonitrile at a PH of 7 (neutral) is added to each of the test tube samples. Mix the samples on a vertex shaker for 3 minutes and transfer to a 20 ml centrifuge tube and place in a TurboVap under 5-psi nitrogen at room temperature and allow it to completely dry. The dry resides are now put in 1ml of acetonitrile for testing (analysis). 4. Chromatographic Condition 10ml of the extract is now taken to be analyzed using a mass spectrometer and a liquid chromatograph.
An equivalent volume of saline solution was added (NaCl 0.16 M; pH = 7) and it was mixed completely. The resultant solution was centrifugated for 30 minutes at 9000 rpm at 4ºC in a rotor Beckman JA-20, eliminating the pellet. The supernatant was collected to obtain the lipoproteins by gradient density ultracentrifugation: 10ml of the yolk solution were taken and then 0.9 g of potassium bromide (KBr) was added. The bromide was dissolved with a smooth agitation, with care not to denature the proteins. Straight afterwards, saline solution was added (NaCl 0.16 M, pH=7) to the 10ml of the yolk solution with a Pasteur pipette, avoiding the sample diffusion, forming two phases and filling the tube completely.