Add 50 to 100 ml of freshly neutralized hot ethyl alcohol and about one ml of phenolphthalein indicator solution. 4. Boil the mixture for about five minutes and titrate it against the standard alkali solution while shaking vigorously during the titration. The weight of the oil taken for the estimation and the strength of the alkali used for the titration shall be such that the volume of alkali required for the titration shall be such that the volume of alkali required for the titration does not exceed 10 ml. Calculation: Acid value= 56.1VN W Where, V=Volume in ml of standard potassium hydroxide or sodium hydroxide used N= Normality of the potassium hydroxide solution or sodium hydroxide solution; and W=Weight in g of the
Effect of acidification Under the reaction conditions, NBD-Cl decompose to give 4-hydroxy-7- nitrobenzo-2-oxa-1,3-diazole which exhibit strong fluorescence and absorbance, obviously the fluorescence and absorbance of this decomposition product can greatly diminished by acidification of the reaction mixture . Therefore, the addition of acid after completion of the reaction is necessary to reduce the interfering background and improvement the sensitivity. It was observed that the use of 0.5 ml of 1.0 M hydrochloric acid was sufficient for suppressing the fluorescence and absorbance of the blank. 3.1.6. Effect of diluting solvent Different solvents such as water, methanol, ethanol and dimethylformamide were tried to dilute the reaction product after completion of the reaction.
This solution was prepared in a 250-mL volumetric flask using distilled water. The solution was made using the following method: The volumetric flask was approximately filled 75% full with distilled water through the funnel. To the volumetric flask, sodium hydroxide pellets were added. The cap/stopper was put on the mouth of the volumetric flask and the solution was gently shaken. Once the sodium hydroxide pellets had dissolved in the solution the flask was again filled with distilled water till the 250-mL mark was reached.
Measurement of lipid peroxidation TBARS, a measure of lipid per oxidation, was measured as described by Ohkawa . Briefly, 1 ml of suspension medium was taken from the 10% tissue homogenate. 0.5 ml of 30% Trichloroacetic acid (TCA) was added to it, followed by 0.5 ml of 0.8% thiobarbituric acid (TBA) reagent. The tubes were covered with aluminium foil and kept in shaking water bath for 30 minutes at 80°C. After 30 minutes, tubes were taken out and kept in ice-cold water for 30 minutes.
Separations were performed on a chiral AGP (100mm×4.6mm id, 5µm particle size) column using UV detector at 301 nm. The mobile phase constituted of 0.025mol L-1 di sodium hydrogen phosphate and Acetonitrile, (90:10 v/v) (pH 7.0) and diluted onto ortho phosphoric acid was used for ph adjustment. An Inertsil ODS (4cm ×4.6mm i.d.) was used as guard column. A flow rate of 1.0 mL/min was maintained throughout the analysis.
This has to be prepared fresh. Procedure : (a) Preparation of calibration curve :(i) Pippet portions of standard NiSO4 solution into 100 ml volumetric flask. Use a series from 50 to 250 µg Ni. (ii) Add 25 ml 1.0 N HCl in 5 ml bromine water. (iii) Cool with cold running tap water and add 10 ml concentrated Ammonium hydroxide.
Solar distillation uses, in common with all distillation processes, the evaporation and condensation modes, but unlike other processes energy consumption is not a recurrent cost but is incorporated in the capital cost of the solar collector. Saline water is filled in the black painted basin of the solar still. This is enclosed in a completely air tight surface. A sloping transparent cover is provided at the top. Then solar radiations are allowed to fall on it.
Question#1: What is distillation? Answer: “A separation technique in which two or more substances are separated into their components from their mixture (liquid or vapour mixture) by the means of heat removal or heat addition is called distillation1.” In liquid mixture distillation, the mixture is heated and less boiling point liquid began to evaporate. Vapors of that liquid then condensed to get purified liquid. Purified liquid is then called condensate. Repetition of distillation on collected liquid is called double distillation, this can be done just to enhance the purity of collected liquid2.
To meet the demand of portable water in these areas economically, solar distillation is a good proportion. Solar stiff recovers portable water from salt water by use of solar radiations. Many types of solar stills were developed for various applications i.e. single effect basin multiple effect, covered, solar concentrator etc. in all types of solar still basin, type solar still is simple and widely used.
leads to contamination of the products. By the use of solar dryers, such problems can be easily overcome. Thus, there is a need to make the solar dryers more efficient and cheaper. There are various types of solar dryers developed and are classified based on the mode of air circulation, such as, natural circulation and forced circulation solar dryers; based on the type of drying,