Water transfer

Alternatively, the following procedure for isolating the glycol may be used. Dilute the partly cooled mixture with 250 ml. of water, transfer to a distilling flask, and distil from an oil bath until the temperature reaches 95°. Transfer the hot residue to an apparatus for continuous extraction with ether (e.g.. Fig. II, 44, 2). The extraction is a slow process (36-48 hours) as the glycol is not very soluble in ether. (Benzene may also be employed as the extraction solvent.) Distil off the ether and, after removal of the water and alcohol, distil the glycol under reduced pressure from a Claisen flask. 

Now run in a solution of 52 g. (53-5 ml.) of pure diethyl carbonate (1) in 70 ml. of anhydrous ether, with rapid stirring, over a period of about one hour. A vigorous reaction sets in and the ether refluxes continually. When the diethyl carbonate has been added, heat the flask on a water bath with stirring for another hour. Pour the reaction mixture, with frequent shaking, into a 2 litre round-bottomed flask containing 500 g. of crushed ice and a solution of 100 g. of ammonium chloride in 200 ml. of water. Transfer to a separatory funnel, remove the ether layer, and extract the aqueous solution with two 176 ml. portions of ether. Dry... 

Dissolve 1 g. of the secondary amine in 3-5 ml. of dilute hydrochloric acid or of alcohol (in the latter case, add 1 ml. of concentrated hydrochloric acid). Cool to about 5° and add 4-5 ml. of 10 per cent, sodium nitrite solution, and allow to stand for 5 minutes. Add 10 ml. of water, transfer to a small separatory funnel and extract the oil with about 20 ml. of ether. Wash the ethereal extract successively with water, dilute sodium hydroxide solution and water. Remove the ether on a previously warmed water bath no flames should be present in the vicinity. Apply Liebermann s nitroso reaction to the residual oil or solid thus. Place 1 drop or 0 01-0 02 g. of the nitroso compovmd in a dry test-tube, add 0 05 g. of phenol and warm together for 20 seconds cool, and add 1 ml. of concentrated sulphuric acid. An intense green (or greenish-blue) colouration will be developed, which changes to pale red upon pouring into 30-50 ml. of cold water the colour becomes deep blue or green upon adding excess of sodium hydroxide solution. 

Add the dimethyl sulphate dropwise during 1 hour whilst stirring the mixture vigorously. Then reflux for 2 hours, with stirring, in order to complete the methylation. Allow to cool, add water, transfer to a separatory funnel, remove the lower layer, and wash once with water, twice with dilute sulphuric acid, and then with water until the washings are neutral to litmus. Add some sodium chloride to each washing as this will facilitate the separation of the two layers for anisole is 0- 996). Dry over anhydrous calcium chloride or magnesium sulphate, and distil from an air bath. Collect the anisole at 151-154°. The yield is 40 g. 

Decant the liquid layer into a 2 5 litre flask, and dissolve the sodium derivative of acetylacetone in 1600 ml. of ice water transfer the solution to the flask. Separate the impiue ethyl acetate layer as rapidly as possible extract the aqueous layer with two 200 ml. portions of ether and discard the ethereal extracts. Treat the aqueous layer with ice-cold dilute sulphimic acid (100 g. of concentrated sulphiu-ic acid and 270 g. of crushed ice) until it is just acid to htmus. Extract the diketone from the solution with four 200 ml. portions of ether. Leave the combined ether extracts standing over 40 g. of anhydrous sodium sulphate (or the equivalent quantity of anhydrous magnesium sulphate) for 24 hours in the ice chest. Decant the ether solution into a 1500 ml. round-bottomed flask, shake the desiccant with 100 ml. of sodium-dried ether and add the extract to the ether solution. Distil off the ether on a water bath. Transfer the residue from a Claisen flask with fractionating side arm (Figs. II, 24, 4r-5) collect the fraction boiling between 130° and 139°. Dry this over 5 g. of anhydrous potassium carbonate, remove the desiccant, and redistil from the same flask. Collect the pure acetji-acetone at 134r-136°. The yield is 85 g. 

Azlactone of a-acetylaminocinnamic acid. Warm a mixture of 29 g. of acetylglycine, 39-5 g. (37 -5 ml.) of redistilled benzaldehyde (Section IV,115), 15 g. of anhydrous sodium acetate and 67 g. (62 ml.) of acetic anhydride (95 per cent.) in a 500 ml. conical flask (equipped with a reflux condenser) on a water bath with occasional stirring until solution is complete (10-20 minutes). Boil the resulting solution for 1 hour, cool and leave in a refrigerator overnight. Stir the sohd mass of yellow crystals with 60 ml. of cold water, transfer to a Buchner funnel and wash well with cold water. (If the odour of benzaldehyde is stih apparent, wash with a little ether.) Recrystallise from carbon tetrachloride or from ethyl acetate-hght petroleum. The yield of azlactone, m.p. 150°, is 35 g. 

A 0.3619-g sample of tetrachloropicolinic acid, C6HNO2CI4, is dissolved in distilled water, transferred to a 1000-mL volumetric flask, and diluted to volume. An exhaustive controlled-potential electrolysis of a 10.00-mL portion of this solution at a spongy silver cathode requires 5.374 C of charge. What is the value of n for this reduction reaction ... 

The first known incidence of pollution from approved herbicides was identified in 1972 in Essex, where tomato plants grown by commercial producers became malformed. The plants had been watered from public water supplies fed from a reservoir. The reservoir in turn abstracted water from a river supplemented by a water transfer scheme, from the River Cam in Cambridgeshire. Pollution from a factory manufacturing 2,3,6-TBA was identified as the cause and the problem was subsequently resolved by treating the effluent. 

A griod example of convection in a process application is the transici of heat from a fire tube to a liquid, as in an oil treater. A current is set up between the cold and the w arm parts of the water transferring the heal from the surface of the fire tube to the bulk liquid. 

Sections (air headers similar to water transfer. if natural convection ... 

The solution is transferred to a 3-I. flask, using about 50 cc. of water for rinsing, and to it is added, with violent (Note 6) shaking, twice its volume (1400-1500 cc.) of 95 per cent ethyl alcohol. The solution is decanted from the gummy residue and the latter extracted three times with methyl alcohol under reflux, each time with 500 cc. of the solvent. In order to remove all the arabinose from the salts the precipitate is dissolved in 200-220 cc. of water, transferred to an evaporating dish, and 400 cc. of 95 per cent ethyl alcohol is stirred in with a heavy rod. The clear alcohol solution is decanted and the solid triturated twice with 300 cc. portions of methyl alcohol. 

Method A. Evaporate 55.0 g of ammonium cerium( IV) nitrate almost to dryness with excess (48 mL) of concentrated sulphuric add in a Pyrex evaporating dish (FUME CUPBOARD). Dissolve the resulting cerium (IV) sulphate in 1M sulphuric acid (28 mL concentrated sulphuric add to 500 mL water), transfer to a 1 L graduated flask, add 1M sulphuric acid until near the graduation mark, and make up to the mark with distilled water. Shake well. 

Procedure. Weigh out accurately about 2.5 g of finely powdered mercury(II) chloride, and dissolve it in 100 mL of water in a graduated flask. Shake well. Transfer 25.0 mL of the solution to a conical flask, add 25 mL water, 2mL 1M hydrochloric acid, and excess of 50 per cent phosphorous(III) acid solution. Stir thoroughly and allow to stand for 12 hours or more. Filter the precipitated mercury(I) chloride through a quantitative filter paper and wash the precipitate moderately with cold water. Transfer the precipitate with the filter paper quantitatively to a 250 mL reagent bottle, add 30 mL concentrated hydrochloric acid, 20 mL water, and 5 mL carbon tetrachloride or chloroform. Titrate the mixture with standard 0.025M potassium iodate in the usual manner (Section 11.127). 

Procedure. Dissolve the sample in distilled water and take an aliquot which should contain not more than 50 pg of phenolic compound. Use the aqueous ammonia to adjust the pH of the solution to 9.7-10.3 (pH meter), and then dilute to 500 mL with distilled water. Transfer the solution to a large separatory funnel, add 1.0 mL of solution A followed by 10 mL of solution B. Shake well to ensure thorough mixing, and then carry out three extractions with successive portions of 15 mL, 10 mL and 5 mL of chloroform (trichloromethane). Combine the chloroform extracts and make up the volume to 30 mL. Measure the absorbance of the extract against a blank of chloroform at a wavelength of 460 nm (blue filter), using 1 cm cells. The colour may tend to fade after 10 minutes and so speed is essential. 

Fig. 8 Temperature, dissolved oxygen saturation, and conductivity profiles in the Sau and Susqueda reservoirs during a water transfer in 2005. Gray banners indicate the depth of the spillways (actual withdrawal depth indicated as an arrow). The path of the Sau Reservoir water inside Susqueda is indicated as a black thick arrow...

Level 1 For each River Basin, identification of the existing problems and their possible causes (the same problem can be originated for more than one cause). For example, the problem No demand satisfaction can be caused by water transfers, surface water and groundwater extraction, agricultural and farm activities (water pollution), a lack of urban and industrial wastewater treatment, Combined Sewer Overflows (CSOs), etc. 

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