Salt water immersion

Minford also studied the effects of four different phosphoric acid processing conditions under stress and intermittent salt-water immersion testing of 6061-T6 aluminum alloys. None of the joints pretreated by varying phosphoric acid anodizing conditions failed after 480 days exposure, even 

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Organic coatings are commonly evaluated using salt water immersion, salt fog or spray, modified salt exposure tests (e.g., salt fog with added SO2), and various cyclic exposure tests. Humidity exposure and water immersion, and, for many applications, physical resistance tests (adhesion, impact resistance, etc.) are widely used preliminary tests. Standard methods for most of these tests are given in compilations of standard tests such as the Annual Book of ASTM Standards (16). Test methods have been extensively reviewed (e.g., 17-23). 

Nonelectrochemical Methods. Nonelectrochemical methods of studying corrosion include exposure tests of performance and primary film property measurements. Standard exposure tests include salt water immersion (3-5% aq. NaCl, usually at room temperature, sometimes oxygen saturated) cyclic immersion (e.g., salt water immersion alternated with drying periods) salt fog or spray (5% aq. NaCl fog,... 

The salt water immersion test (SWI) and the standard salt spray (fog) test (SS) were conducted for both ISPCs and control baking enamels applied on bare CRS, iron phosphated B-1000, and BD+P60 panels. The painted coupons of about 1.0 mil dry film thickness cured at 163 C for 15 minutes were X-cut through the film to the substrate and then either immersed in a 3% NaCI solution (SWI test) or subjected to a continuous salt-solution spray in a test chamber (SS test). After a specified duration of testing, the specimens were removed from the salt solution, and the coated surface was immediately dried. A DUCK brand tape (Manco, Inc., Westlake, OH) was applied over the X-cut and then removed, and the protective performance was... 

Guide for Selecting Chlorinated Rubber Painting Systems Chlorinated Rubber Painting System for Salt Water Immersion Chlorinated Rubber Painting System for Fresh Water Immersion Chlorinated Rubber Painting System for Marine and Industrial Environments... 

The guide covers vinyl painting system for blast cleaned or pickled steel. These systems are suitable for use on parts or structures exposed in Environmental Zones lA (interior, normally dry), 2A (frequently wet by fresh water), 2B (frequently wet by salt water), 2C (fresh water immersion), 2D (salt water immersion), 3A (chemical, acidic), and 3B (chemical neutral). The color of the finish paint must be specified. 

Painting System Specification No. 15.01 Chlorinated Rubber Painting System for Salt Water Immersion... 

Salt water immersion No event (terminal corrosion)... 

Magnesium oxide is a typical acid scavenger for chlorinated mbbers. Compounds containing zinc oxide or magnesium oxide may tend to swell upon immersion in water. These inorganic salts have some water solubiHty and osmotic pressure causes the vulcanizates to imbibe water to equalize pressure (8,9). As such, vulcanizates tend to sweU more in fresh (distilled) water than in salt water. To minimize water sweU, insoluble salts such as lead oxides can be substituted. Because of the health concerns associated with lead, there is much mbber industry interest in other acid acceptors, such as synthetic... 

Composite materials must survive in the environment to which they are subjected at least as well as the conventional materials they replace. Some of the harmful environments encountered include exposure to humidity, water immersion, salt spray, jet fuel, hydraulic fluid, stack gas (includes sulfur dioxide), fire, lightning, and gunfire as well as the combined effects of the space environment. 

Reference to Table 4.19 will show that greatly superior corrosion rates of the high-purity alloys are only in evidence in the more severe conditions of test by immersion in salt water, and that in less drastic conditions, and especially in industrial atmospheric exposure, there is little to choose between the alloys. 

In considering the corrosion of magnesium and its alloys it is important to examine the methods available for assessing corrosion tendencies and particularly those known as accelerated tests. Tests carried out by immersion in salt water or by spraying specimens regularly with sea-water are worthless as a means of determining the resistance of magnesium alloys under any other than the particular test conditions. Extrapolation to less corrosive conditions is not valid and even the assessment of the value of protective measures by such means is hardly possible. The reason is to be found in the fact that corrosion behaviour is directly related to the formation of insoluble... 

Zinc roofs are quite satisfactory at the coast, where they receive a large amount of salt-water spray, and many British piers have been covered with sheet zinc which has lasted 50 years and more. Most of the zinc actually immersed in sea-water is in the form of zinc coatings, the behaviour of which is discussed in a later section of this book (see Section 14.4). Experience with these coatings has proved the value of zinc in sea-water compared with many other metals in this environment". 

Fish Collection, Maintenance, and Treatment. Adult fish were collected near Mount Desert Island, Maine, or Marineland, Florida, and were acclimated in aquaria equipped with continuously flowing seawater or in live cars immersed in salt water for at least 24 hr before use. For induction studies little skates were injected IP with 10 mg/kg 1,2,3,4-dibenzanthracene in corn oil on days 1, 2, and 3 and were sacrificed on day 10. Control fish were injected with corn oil only. 

U) Non-Faradaic electrochemical methods. Conductometric methods have been extensively used by scientists and conservators for monitoring the content of salts removed during water immersion treatments of ancient tiles and archaeological ceramic remains. In a different manner to IC, this technique provides the total ionic... 

The effect of temperature difference on the segregation coefficient was determined experimentally. Although the segregation coefficient data vary with concentration, the effect is small in this type of system and was considered to have no significance in the economic study. Tubes ranging in size from 7/16 to 1 inch containing salt water were immersed in a constant temperature bath and the segregation coefficient was determined. 

A cucumber (top) shrivels into a pickle (bottom) when immersed in salt water, because osmotic pressure drives water from the cucumber s cells. 

Immersion in pure water must lead to the same result as in a saturated atmosphere. If water contains solutes, its vapor pressure decreases. The corresponding equilibrium concentration, linked to the water activity, is proportional to the water vapor pressure. In other words, the water equilibrium concentration is a decreasing function of the solute concentration salt water is less active than pure water. 

Four grams of chromium (VI) oxide (0.04 mol) is dried at 110° in vacuo for 4 hours and is then cooled in an ice-salt mixture. Fifty milliliters of pyridine (0.63 mol) is also cooled in a 300-ml. Erlenmeyer flask. While the 50 ml. of pyridine is shaken in the flask immersed in an ice-salt-water mixture, the chromium(VI) oxide is slowly added. The flask is stoppered, and the mixture is agitated until all solid particles have dissolved. A larger amount of pyridine may be used to hasten solution, if desired. Cooling is necessary, since the reaction generates enough heat to bring about oxidation of the pyridine unless the temperature is controlled. 

A useful spot test utilizes the fact that a suspension of red nickel dimethylglyoxime in water when treated with a neutral or acetic acid solution of a palladium salt yields the yellow palladium dimethylglyoxime, which is sparingly soluble in dilute acids. The test is best performed with dimethylglyoxime paper the latter is prepared as follows. Immerse drop-reaction paper in a 1 per cent alcoholic solution of dimethylglyoxime, dry, then immerse again in a solution of 05m nickel chloride rendered barely ammoniacal. The nickel complex precipitates wash thoroughly with water, immerse in alcohol and dry. 

Foods are dehydrated by immersion in liquids with an aw lower than the food. By using sugars and salts, water diffuses out of the food into solution while solute diffuses from solution into the food. 

Bisphenol A diepoxy resins were modified using quaternary ammonium salts to produce resins capable of being cast to give good bactericidal activity against Escherichia coli, and retained the property after long term water immersion. They have the advantage that they do not release hazardous toxic compounds. 13 refs. 

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