Wetting, paper testing

Procedure Pollen develops on the nutrition medium, forming pollen tube (Fig. 3). The nutrient medium for pollen was 10% sucrose solution and tested compounds were also dissolved in 10% sucrose. The pollen develops till the formation of pollen tube that lasts from 2-3 h (fresh collected and one week stored pollen) to 24 h (stored > 1 week, but < 1.5-2 months). All experiments were done at room temperature 20-22 °C. The growth occurred in the solution studied (0.05 ml = 1 drop) on the slides (object glasses) put on wet paper in Petri dishes. Five ml of water was added to the bottom of every dish and 4-5 dishes with the slides were used per treatment. Using light microscope, we determined the microspores germination (%) 2-24 h after moistening. The number of developed pollen tubes was counted. 

This paper utilizes data that were acquired as part of the Environmental Protection Agency s Shawnee Wet Scrubbing Test Program, and is presented with the support and encouragement of John F. Williams, Shawnee Project Officer, EPA Industrial Environmental Research Laboratory, Research Triangle Park, NC. 

The alkalinity of the deeply colored solution can be tested with phenolphthalein paper. The edges of the wetted paper become visibly red. One should be sure to test the aqueous solution and not the separated thiazole floating on top of the liquid. 

Selenium tone for 5 minutes. The dilution will vary depending on the paper. The first time you work with a new paper test the first print in a dilution of 1 19. Have an identical wet but untoned print to compare against. If a color shift occurs try a 1 29 dilution, then 1 39 if necessary. Color shifts will usually be observed at about the 3 minute mark. 

Chloride Determine as directed in the Chloride Limit Test under Chloride and Sulfate Limit Tests, Appendix IIIB, using 100 mg of sample dissolved in 100 mL of water. Any turbidity produced by a 10-mL portion of this solution does not exceed that shown in a control containing 20 (ig of chloride (Cl) ion. Cyanide Dissolve 10 mg of copper sulfate in a mixture of 8 mL of water and 2 mL of 6 IV ammonium hydroxide. Wet a strip of filter paper with this solution, and place the wet paper in a stream of hydrogen sulfide. When 1 drop of a 1% solution of the sample is placed on the brown reagent paper, no white circle appears. 

Acidify the bicarbonate solution (aqueous extract), still in the separatory funnel, with 6 mL of 1 M sulfuric acid. This step should be performed without delay, to avoid hydrolysis of the aspirin. The acid must be added slowly in small portions. Mix well only after most of the carbon dioxide evolution has ceased. The pH at this point should be 1 to 2 (pH test paper). Extract the acidified solution with eight separate 10-mL portions of methylene chloride and filter through a methylene chloride-wet paper into a 100-mL volumetric flask. Dilute to volume. Then, dilute further a 5-mL portion of this solution to 25 mL with methylene chloride in a volumetric flask. 

Apply 9V to the copper wire electrodes contacting the test media through the wetted paper separator. 

Upon entering the test chamber, the test subject shall be given a 6-inch by 5-inch piece of paper towel, or other porous, absorbent, single-ply material, folded in half and wetted with 0.75 ml of pure lAA. The test subject shall hang the wet towel on the hook at the top of the chamber. An lAA test swab or ampule may be substituted for the lAA wetted paper towel provided it has been demonstrated that the alternative lAA source will generate an lAA test atmosphere with a concentration equivalent to that generated by the paper towel method. 

The filter-paper technique is much faster. A piece of filter paper is placed on the surface to be tested, and deionized water is squirted on it until it is saturated. The wet paper is then placed on an instrument (such as the SCM-400 from Elcometer) that measures its resistivity. As in the conductivity measurements discussed above, when this is used for repainting applications, it is not certain how much of the resistivity of the paper is due to chlorides and how much is due simply to rust in the test water. In all, the technique is reliable and simple to implement, although initial equipment costs are rather high. 

This is a test to determine the water resistance of a coated paper. After wetting the test strip at constant speed and uniform pressure to create a precisely defined moisture content, the strip is printed with the testing ink while moving at constant or increasing speed through the press. 

Place 84 g. of iron filings and 340 ml. of water in a 1 - 5 or 2-litre bolt-head flask equipped with a mechanical stirrer. Heat the mixture to boiling, stir mechanically, and add the sodium m-nitrobenzenesulphonate in small portions during 1 hour. After each addition the mixture foams extensively a wet cloth should be applied to the neck of the flask if the mixture tends to froth over the sides. Replace from time to time the water which has evaporated so that the volume is approximately constant. When all the sodium salt has been introduced, boU the mixture for 20 minutes. Place a small drop of the suspension upon filter paper and observe the colour of the spot it should be a pale brown but not deep brown or deep yellow. If it is not appreciably coloured, add anhydrous sodium carbonate cautiously, stirring the mixture, until red litmus paper is turned blue and a test drop upon filter paper is not blackened by sodium sulphide solution. Filter at the pump and wash well with hot water. Concentrate the filtrate to about 200 ml., acidify with concentrated hydrochloric acid to Congo red, and allow to cool. Filter off the metanilic acid and dry upon filter paper. A further small quantity may be obtained by concentrating the mother liquid. The yield is 55 g. 

For some dipped work, wet gel strength measurement is carried out, where the gel is deposited onto preformed, tissue paper dumbeUs, and the load necessary to break the dumbeU-shaped test piece is measured. 

Wipe sampling involves swiping a dry or wet (use of a solvent or other liquid besides water in eommonplaee) eloth, glass fiber filter paper, or swab over the surfaee of a potentially eontaminated objeet and performing a laboratory analysis. Both the inner and outer surfaees of PPE should be tested to eheek for permeation. Skin ean also be tested using this wipe sampling [1]. 

The solvents were evaporated in vacuo, and the residue was taken up in 80 ml of 3M hydrochloric acid. After addition of 220 ml of water, the insoluble material was filtered off, washed with 100 ml of water and then dried. The insoluble material weighed 9.5 g and was mainly unreacted bromo compound. The filtrate was reacted with 50 ml of 7 M NaOH, extracted three times with methylene chloride (50 m -t 2 x 25 ml portions), dried over potassium carbonate, and then evaporated. The yield of residue was 26.8 g which corresponds to 71.4% of the theoretical yield. This residue was a colorless solidifying oil and was dissolved in 200 ml chloroform. Hydrogen chloride was bubbled in until a sample of the solution tested acidic to wet pH indicator paper. A precipitate was obtained and recovered by filtration. The precipitate was washed with chloroform and dried. The melting point was determined to be from 246 Cto247.5°C. 

The inspector s working standard for the surface finish of blast-cleaned steel is now the new British Standard . In the special circumstances where absolute freedom from soluble contaminants such as ferrous sulphate is necessary, the specification should include reference to a test for removal of such residual salts, e.g. the potassium ferricyanide test . The area to be sampled should be wetted with a fine spray of distilled water and the paper held against it. The development of blue spots on the paper indicates the presence of ferrous salts on the surface. 

Odor. Det odor in accordance with ASTM D1296. In this test strips of filter paper are dipped into specimen and reference standards, and odor comparisons are made of characteristic odor when the strips are wet, and residual odor remaining after the strips appear dry. If an odor persists on the sample paper after the point in time when no odor is detectable on the standard paper, the odor is reported as residual ... 

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