Transferred drop tests

Information on immunological effects in humans after dermal exposure to 2,4-DNP is limited. Three methods of skin testing were performed on 157 people, 117 of whom were patients with hay fever, asthma, or urticaria (Matzger 1934). For the patch test, 10 mg of sodium 2,4-DNP was applied to the forearm or back under waxed paper. For the scratch test, 2 mg sodium 2,4-DNP in saline or 2 drops of a 2% aqueous solution was rubbed on a scarification. For the intradermal test, 0.01-0.02 ml of 0.001%, 0.01%, 0.1%, or 1% sodium 2,4-DNP was introduced in the upper arm. In the indirect or passive transfer test, blood serum from a patient with a violent clinical reaction to DNP was introduced intradermally in nonallergic subjects. After 24 hours, the sites of passive transfer were tested intradermally with 2,4-DNP. The direct tests and the passive transfer test were negative. 

Fig. 9.9 Agglomerate strength testers top) hydraulic four-column press for the determination of compression strength bottom) from left, rotating tube for measuring degradation at transfer points, drop test arrangement, and drum abrasion tester...

Place 10 ml. of 1% starch solution (prepared as described above) in a boiling-tube, add 2 ml. of 1% sodium chloride solution and place the tube in a water-bath maintained at 38-40 . Place about 5 ml. of water in a series of test-tubes and to each add a few drops of 1% iodine solution. Now add 4 ml. of the diluted saliva solution to the starch solution, mix well and note the time. At intervals of about 30 seconds transfer 2 drops of the reacting mixture, by means of a dropping tube, to one of the test-tubes, mix and note the colour. As in the previous experiment, the colour, which is blue at first, changes to blue-violet, red-violet, red-brown, pale brown, and finally disappears at this stage the solution will reduce Fehling s solution. If the reaction proceeds too quickly for the colour changes to be observed, the saliva solution should be diluted. 

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. 

Control of an evaporator requires more than proper instrumentation. Operator logs snould reflect changes in basic characteristics, as by use of pseuao heat-transfer coefficients, which can detect obstructions to heat flow, hence to capacity. These are merely the ratio of any convenient measure of heat flow to the temperature drop across each effect. Dilution by wash and seal water should be monitored since it absorbs evaporative capacity. Detailed tests, routine measurements, and operating problems are covered more fuUy in Testing Procedure for Evaporators (loc. cit.) and by Standiford [Chem. Eng. Prog., 58(11), 80 (1962)]. 

The alkaline solution of thymol is made up to 100 or 200 c.c. as the case may require, using a 5 per cent, soda solution. To 10 c.c. of this solution in a graduated 500 c.c. flask is added a normal iodine solution in shgbt excess, whereupon the thymol is precipitated as a dark reddish-brown iodine compound. In order to ascertain whether a sufficient quantity of iodine has been added, a few drops are transferred into a test tube and a few drops of dilute hydrochloric acid are added. When enou iodine is present, the brown colour of the solution indicates the presence of io ne, otherwise the liquid appears milky by the separation of thymol. If an excess of iodine is present, the solution is slightly acidified with dilute hydrochloric acid and diluted to 500 c.c. From this 100 c.c. are filtered,off, and the excess of iodine determined by titration with normal solution of sodium thiosulphate. For calculation, the number of cubic centimetres required is deducted from the number of cubic centimetres of normal iodine solution added and the resultant figure multiplied by 5, which gives the number of cubia centimetres of iodine required by the thymol. 

Test, P. L., AStudy of Heat Transfer and Pressure Drop Under Conditions of Laminar Plow in the Shell Side of Cross Baffled Heat Exchangers, Paper No. 57-HT-3, ASME-AlChE Heat Transfer Conference, ASME, New York, NY (1957). 

Procedure. Dissolve 0.1 g of the sample in 10 mL purified methanol and transfer 1.0 mL of this solution to a stoppered test-tube. Add 1.0 mL of solution A and one drop of concentrated hydrochloric acid, then place the stoppered tube in a beaker of boiling water for 5 minutes. Cool, and then add 5.0 mL of the potassium hydroxide solution. Measure the absorbance of the solution at 480 nm (blue-green filter) against a blank obtained by subjecting 1.0mL of purified methanol to the above procedure. 

Heat and reflux a 5-g portion of soil sample with 50 mL of methanol-phosphate buffer (pH 7)-water (15 7 28, v/v/v) solvent mixture in a round-bottom flask for 1 h. After cooling, transfer a 10-mL portion of the supernatant to a test-tube and mix with 11 mL of 0.02M H3PO4 solution. Load this solution on to a silica-based SPE cartridge (Analytichem International Clin-Elut 1020) at a flow rate of 1-2 drops per second. Discard this fraction. Elute the analytes with 30 mL of dichloromethane. Concentrate the eluate to dryness with air in a water-bath at a temperature of 40 °C (do not use vacuum). Dissolve the residues in 5mL of HPLC injection solution [900 mL of water - - 50 mL of phosphate buffer (pH 7) 4-50 mL of ACN 4-4 g of TBABr]. Pinal analysis is performed using liquid chromatography/ultraviolet detection (LC/UV) with a three-column switching system. 

Use a stirring rod to transfer 1 drop of hydrochloric acid (test tube number 1) to a piece of red litmus paper. Then transfer 1 drop of hydrochloric acid to a piece of blue litmus paper. 

This heat-transfer region has been more widely studied than either Region II or IV. However, the methods for evaluating the parameters have not been tested over a wide range of experimental conditions. Equations (71) and (72) must be coupled with a knowledge of the pressure drop, holdups, and other system parameters if the temperature and mass flow-rate profiles are to be determined. As mentioned earlier in this chapter, the pressure drop and holdups in phase change systems can be estimated by using the Martinelli-Nelson Correlation. 

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