Measure out 1,575g of oxalic acid crystals into the glass beaker. 5. Determine the mass of the beaker and NaOH together. 6. Rinse a 250 ml volumetric flask with deionized water.
The product dissolved in the dry ether after washing with toluene. Using filtration sodium acetate was separated, and the filtrate was evaporated to obtain syrup and fractionated at a boiling point of 133-136 °C. The obtained product dissolved in hydrogen bromide of glacial acetic acid and this mixture reaction kept in an ice bath for 1hr. According to procedure, the product was methylated to obtain 1bromo-2, 3, 4, 6-tetramethylglucose.
The first step was to disperse 4 g of block P123 (EO20PO70EO20) in 40 ml of distilled water and 120ml of 2 M aqueous HCl was added with stirring at 350 C for about 3 h. To this solution, 4 g of TEOS was added and continuously stirred at 400 C for 24h. Then the resulting gel was
70 mm) to remove debris and suspended materials and then poured into a 2 liter separatory funnel. For the first LLE, the mixture of 100 ml n-hexane and dichloromethane (1:1 v/v) was added and shaken vigorously for 2 min before two phase separation. The water-phase was drained from the separatory funnel into a 1000 ml beaker. The organic-phase was carefully poured into a glass funnel containing 20 g of anhydrous sodium sulfate through a 200 ml concentrator tube. Following the second and third LLE, the water-phase was poured back into the separatory funnel to re-extract with 50 ml of the same solvent mixture.
For 63.0℃, the flask was cooled when the solution in the flask become almost empty. 25 mL of chloroform and 25 mL acetone were added to the flask and distillation was started again. Samples (3V, 3L) were collected at about
In to a conical flask containing 50ml of 95% ethanol, 10g of the macerated sample was placed and maintained at a temperature of 70-80˚c in a water bath for 20 minutes with periodic shaking. The supernatant was decanted, allowed to cool. The ethanol concentration of the mixture was brought to 85% by adding 15ml of distilled water and it was further cooled in a container of ice water for about 5 minutes. The mixture was transferred into a separating funnel and 25ml of petroleum ether was added and the cooled ethanol was poured over it. The funnel was swirled gently to obtain a homogenous mixture and it was later allowed to stand until two separate layers were obtained.
If the pH is less than 6.0, it must be boiled for 15 minutes and cooled at room temperature. (c) Sodium hydroxide solution (0.02 N): 1N sodium hydroxide solution is prepared by dissolving 40 g of L.R grade NaOH in distilled water and diluting it to 1000 ml. For the preparation of 0.02 N NaOH solution, take 20 ml of IN NaOH and dilute it to 1000 ml. 0.02 N NaOH can be standardize against standard potassium acid phthalate. 1.0 ml 0.02 N NaOH = 1.0 mg CaCO3 (d) Phenolphthalein indicator: Dissolve 0.5 g of phenolphthalein in 100 ml alcohol and water.
Firstly, 0.3 g Fe3O4 was ultrasonically dispersed into 150 ml solvent (Vmethanol/Vwater=1/1) for 20 min to obtain a uniform suspension. A 100 ml alkaline solution (0.32 g Na2CO3, 0.48 g NaOH) was added dropwise into the suspension until pH ca. 10.0 and kept for 5 min, then another 100 ml salt solution (1.02 g Mg(NO3)2⋅6H2O and 1.2 g Al(NO3)3⋅9H2O) and above alkaline solution were simultaneously added maintaining the pH in 9.5-10.0. The resultant was stirred for 5 min followed separation by using a magnet and thoroughly washing with deionized water and alcohol and dried at 60 °C overnight giving product Fe-Mg/Al
A 100 ml Erlenmeyer (flask 1) was prepared containing 2.5 ml soil solution and 95 ml of mineral salt medium (MSM) (KH2PO4, 1.52 g; Na2HPO4, 2.44 g; CaCl2.2H2O, 0.50 g; MgSO4.7H2O, 0.20 g; (NH4)2SO4, 0.50 g; trace element, 10ml) and 2.5ml of synthetic mixture of petroleum hydrocarbons (gas oil, kerosene, furnace oil; 1:1:0.1) as sole source of carbon. The flask was incubated at 22 ± 2 o C. After 15 days, 2.5 ml of flask1 was transferred to a second flask (flask 2) with the same condition as flask 1. These incubating -transferring were repeated for 4 times. The experiments were carried out with soil from an uncontaminated area around were the sample is collected. The soil samples were sieved by a 2-mm screen and were sterilized three times by autoclaving at 200 o C for 30 min followed by incubation for 24 h at 37 o C. Six 250 ml Erlenmeyer flasks were prepared for each of the soils
Then add 25 ml of the solvent and displace the air above the liquid with Co2. 3. Then add 1 ml of the potassium iodide solution, stopper the flask and allow it to stand for 1 min. (with shaking). 4.