Marble test

As the theoretical calculation does not always result in entirely correct results, practical corrosion tests are carried out. Aggressivity towards CaC03 is experimentally determined by the so-called Heyer s test (marble test). In these experiments water is brought in contact with CaC03 and after achieving equilibrium the increase or the loss of calcium or hydrogen carbonates is determined. 

The content of aggressive CO2 can be determined by the Heyer marble test. In this case aggressive CO2 dissolves calcium carbonate (marble) to form hydrogen carbonate and thus the acid neutralization capacity of water increases up to pH 4.5 (total alkalinity). The increase of the acid neutralization capacity is proportional to the content of the originally present aggressive CO2 [14, 21]. 

If the free CO2 is higher than the balancing CO2, the water is said to be aggressive (to limestone, and this can be determined by the "marble test"). 

Figure 6. US Marble using the RAPTOR to test for toxins and pathogens in drinking water in Bahrain.

A rapid, nondestructive method based on determination of the spatial distribution of ATP, as a potential bioindicator of microbial presence and activity on monuments, artworks, and other samples related to the cultural heritage, was developed [57], After cell lysis, ATP was detected using the bioluminescent firefly luciferin-luciferase system and the method was tested on different kinds of surfaces and matrices. Figure 3 reports the localization of biodeteriogen agents on a marble specimen. Sample geometry is a critical point especially when a quantitative analysis has to be performed however, the developed method showed that with opti-... 

When Sir James Hall (1761-1832) read of this work, he recalled his own experiments on the effects of compression in modifying the effects of heat, and concluded that the changes which, with true scientific modesty, he [Hatchett] ascribes to an unknown cause, may have resulted from various heats acting under pressure of various force (19). Sir James subjected the theories of the geologists to the test of chemical experiment and showed that when limestone is heated under pressure, it is not converted into quicklime but into crystalline marble. 

The purpose of die tests described on the paper of Missouri School of Mines (Ref 7) is to help in predicting expl performance in rock from performance in water. Four expls were tested both in water and in rock so that direct comparison of the results of the two methods of testing could be made. The rock tests were made at a granite quarry operated by the Consolidated Quarries Division of the Georgia Marble Co, near Lithonia, Ga. The rock was uniform with sp gr ca 2.6 and propagation velocity of about 18000 ft/sec. The underwater tests were made in a deep pond at the Armour Foundation test facility near Coal Ciry, Illinois. Water had sp gr 1.0 and propagation velocity 5000 ft/sec... 

Add 50 pi sample (homogenate) and 200 pi 33% KOH to a test tube. Use high test tubes because of concentrated sulfuric acid. Boil for 20 min with the tubes covered with a glass marble. After cooling on ice-H20 add 1.75 ml H20. 

Pour a hydroiodic acid solution into three test tubes. Add solutions of sodium acetate and lead acetate to the first tube, of silver nitrate (one or two drops) to the second one, and put a small piece of marble into the third tube. Write the equations of the reactions for all the processes occurring in the given experiment. 

The article is tested as to purity by the methods detailed under Calcium Oxide from Marble, on page 83. 

Prepare 10 mL of a DNA solution in Tris buffer I at a DNA concentration of about 20 ng/mL. Measure and record the Am. It should be around 0.4 absorbance units. Transfer 3.0 mL of the DNA solution into each of three test tubes. Place a marble over the top of each tube. Maintain one tube at room temperature and place the other two in a 90°C water bath for 15 minutes. After the incubation period, remove the tubes. Quick-cool one heated tube in an ice bath and allow the other heated tube to cool slowly to room temperature over a period of about 1 hour. Measure and record final A26q readings on each of the three tubes. 

Care must be taken to exclude air bubbles when weighing in water, and this is helped if a trace of detergent is added and/or the test piece quickly dipped in ethanol before weighing. If the rubber is less dense than water, then a sinker must be used in the same manner as for density measurements (see Chapter 7). The test piece is then immersed in the test liquid for the chosen time at the chosen temperature. At least 15 times the test piece volume of liquid should be used and care must be taken to ensure that the rubber is exposed on all sides to the liquid. This can be done by suspending the test pieces on wires or it is satisfactory to rest them on glass marbles. 

Marbles Romanowo G6rne I 0.67 (2.07) 1.97 1.7-4.2 1.7-2.3 where result (4.2) was obtained, where a fine crack, hardly visible before test... 

A nine-component composition has been tested in developing a new composite material. Three components were the binder of the composite material polyester EPX-279-1, polyester EPX-187-3 and styrene. These materials have been used as fillers ash, marble powder, glass microspheres, saran microspheres, wollastonite and powder made by grinding shells. Component properties with variation range of their proportions are given in Table 3.58. 

Mouse cage dimensions vary, but this test has been used effectively with 26 x 16 cm (for 6-8 marbles) or 30 x 20 cm (for 20 marbles) (14). Marbles should be placed on the surface of the bedding in a regular pattern, roughly 4 cm apart. 

Use a new clean cage with fresh bedding for each animal. Wash the marbles with ethanol after each test. 

Nicolas, L. B., Kolb, Y. and Prinssen, E. P. (2006) A combined marble burying -locomotor activity test in mice a practical screening test with sensitivity to different classes of anxiolytics and antidepressants. Eur J Pharmacol 547, 106-115. 

The STR was equipped with temperature, pH, and Po2 control units. Only one Rushton impeller was used to homogenize the system. Almost 1L of the culture medium supplemented with the carbon sources was used during the test runs. In the configuration with marbles, the total volume occupied by marbles (average diameter of 16 mm) was roughly 350 mL. In the configuration with the metal cylinder around the stirrer axle, the volume available in the external cavity was 565 mL. 

Surface area. Using a large mortar and pestle, crush and pulverize about 0.5 g of marble chips. Place the crushed marble chips into one large test tube and 0.5 g of uncrushed marble chips into another. Add 2 mL of 6 M HC1 to each test tube and note the speed of bubbling of the C02 gas. Record your data on the Report Sheet (4). 

Place a few small lumps of marble (calcium carbonate) in a small porcelain crucible. Cover the crucible in order to keep in the heat, and heat it strongly for 20 minutes with a Bunsen flame. When the product has cooled, wet each lump with a single drop or two of water and wait a few minutes, if necessary, to observe the effect. The lumps should grow very hot, and steam be driven off. Then wet the product with somewhat more water, and test the reaction of the moist mass towards litmus. The litmus is colored strongly blue by the suspension. 

Surround the flask of aluminum chloride with cracked ice and water, and pass the gas into the solution until it is saturated. Observe the usual caution about disposing of the hot contents of the generator. Collect the crystalline precipitate in a 5-inch funnel containing a marble and dry it as completely as possible with suction while pressing the crystal mass with the round end of a test tube. Place the product in a 4-inch porcelain dish in the desiccator over solid sodium hydroxide. It will take several days for the excess of hydrochloric acid to evaporate from the crystals. When it is dry put the product in an 8-ounce cork-stoppered bottle. 

Accurate comparison of results requires knowledge of reaction site density per unit surface area. Calcite materials used for kinetic study have included natural marbles, limestones, hydro-thermal crystals of Iceland spar, tests of calcareous organisms and laboratory and commercial precipitates. Surface areas, estimated by BET methods and graphical methods (based on particle size distribution) range from about 0.005 to 2 m g . There are apparent discrepancies between graphical and BET surface areas and the question is raised as to which type of surface area estimate is most representative of the reacting surface area. 

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