Bottle test operations

The chemical, injected continuously in-line during plant operations, may be better dispersed than in the bottle test where a specific volume is added. 

A further simple, but very efficient and powerful technique to obtain important information especially on the purification by melt crystallization is the so-called cold finger experiment. Compared to the bottle test, more but simple lab equipment is required for this setup. Figure 15.7 shows the essential parts of a cold finger apparatus allowing a static operating mode. 

OECD 301D, Ready Biodegradability Closed Bottle Test, Guidelines for Testing of Chemicals, Organisation for Economic Co-operation and Development, Paris, Erance, 1992. 

A recirculating dynamic test method can be used when it is desired to simulate fleld flow or operational conditions. Some of the parameters that should be controlled are the velocity of the corrosive medium, the oihwater ratio (in case of oil-field inhibitors), temperature, and dissolved gas and/or air concentration. Variables that can be imposed are the type of corrosive medium, the concentration of inhibitor, the effect of precorrosion of the test specimen, and the type of inhibitor treatment. This type of flow test provides a more severe test of inhibitor film life than the static bottle test. It furnishes a useful technique for the study of variables affecting inhibitor performance. Correlation between laboratory tests and field use of inhibitors is better using this technique than it is using data from the static test. 

Fat Content of Milk. Raw milk as well as many dairy products are routinely analyzed for their fat content. The Babcock test, or one of its modifications, has been a standard direct measure for many years and is being replaced by indirect means, particularly for production operations. The Babcock test employs a bottle with an extended and caHbrated neck, milk plus sulfuric acid [7664-93-9] to digest the protein, and a centrifuge to concentrate the fat into the caHbrated neck. The percentage of fat in the milk is read direcflv from the neck of the bottle with a divider or caHper, rea ding to... 

The water slowly dripping from the bottle during the test permits maintaining in apparatus a slight vacuum of 50—60cm of water, which prevents the escape of alcohol and ether from apparatus during the test Procedure, It may be subdivided into the following operations ... 

A very simple type of a bubble column, which was not mentioned above is a gas-wash bottle. This very small-scale system (VL = 0.2-1.0 L) may be used for basic studies, in which general effects (e. g. influence of pH and/or buffer solutions specific ozone dose) are to be assessed. Its use is not recommended for detailed studies, because the mass-transfer coefficient is often low and its dependency on the gas flow rate is unknown or difficult to measure. Often there is no possibility to insert sensors or establish a reliable measuring system for exact balancing of the ozone consumption. An optimal mode of operation would comprise treatment of the (waste-)water for a certain period of time, preferably without withdrawal of solution during the ozonation. In this way different ozonation conditions can be tested by varying the ozonation time or the ozone gas concentration. A variation of the gas flow rate is not recommended. 

Bottle/jar tests do have limitations. It can be difficult to reproduce the actual process temperature, pressure, and flow conditions, so in some cases the results may not scale-up to actual operational conditions. Mikula and Munoz [68] show the differences in jar test performance that can result from wall effects alone. 

Delta receptor knockout mice were exposed to alcohol, and drinking was examined in the two-bottle choice and operant self-administration paradigms [73,80]. First, naive animals consumed alcohol as wild-type animals in the two-bottle choice. After training to self-administer alcohol, the mutant mice developed a stronger preference for alcohol and consumed more than wild-type mice in both tests. After alcohol experience also, their anxiety decreased and reversed to wild-type levels. This suggests that, in the case of alcohol, delta receptor activity may partly influence addictive behavior indirectly, by modulating anxiety-like responses. Whether this applies to selfconsumption of other drugs of abuse remains to be determined. 

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