Sodium volatility, effect

Sodium Hydroxide and Sodium Acetate Effect on NH Volatility. Ammonia volatility measurements at various concentrations of so-dium hydroxide and sodium acetate at 80°C are given in Tables 23 and 24 respectively. Data on the effect of sodium hydroxide were measured using an ammonia probe from Orion Research Company. 

Fig. 11. Effect of coal rank on furnace sizing (constant heat output) (82), where W = width, D = depth, and h and H are the heights indicated. A represents medium volatile bituminous B, high volatile bituminous or subbituminous C, low sodium lignite D, medium sodium lignite and E, high...

This is a special chemical effectively used for column bioreactors. It is a volatile compound and strong oxidising agent. It boils at ambient temperature, therefore the solution of ethylene oxide (liquid phase) must be stored in a refrigerator (4 °C). An excellent oxidising agent such as a 3% sodium hypochlorite is used for chemical sterilisation of equipment. 

N-Nitrosamine inhibitors Ascorbic acid and its derivatives, andDC-tocopherol have been widely studied as inhibitors of the N-nitrosation reactions in bacon (33,48-51). The effect of sodium ascorbate on NPYR formation is variable, complete inhibition is not achieved, and although results indicate lower levels of NPYR in ascorbate-containing bacon, there are examples of increases (52). Recently, it has been concluded (29) that the essential but probably not the only requirement for a potential anti-N-nitrosamine agent in bacon are its (a) ability to trap NO radicals, (b) lipophilicity, (c) non-steam volatility and (d) heat stability up to 174 C (maximum frying temperature). These appear important requirements since the precursors of NPYR have been associated with bacon adipose tissue (15). Consequently, ascorbyl paImitate has been found to be more effective than sodium ascorbate in reducing N-nitrosamine formation (33), while long chain acetals of ascorbic acid, when used at the 500 and lOOO mg/kg levels have been reported to be capable of reducing the formation of N-nitrosamines in the cooked-out fat by 92 and 97%, respectively (49). 

Sodium-neutralized salts of montanic acid (e.g. Licomont NaV) are also effective nucleators for PET. Montanic wax consists of a mixture of straight-chain, saturated carboxylic acids with chain lengths in the range of 26 to 34 carbon atoms. The low volatility and high thermal stability of montanic acid waxes makes them a suitable nucleating agent for engineering plastics such as PET and PBT. 

C. Effect-of sodium hydroxide and sodium acetate on NH3 volatility at 80°C... 

The effects of sodium acetate and sodium hydroxide on NH3 volatility at 80°C were studied by two methods. Data on the effect of sodium acetate were measured in the same apparatus used to measure the NH3-H0O data shown in Figure 1. In this case, sodium acetate was also added to the liquid phase with subsequent... 

TABLE 24. Effect of Sodium Acetate Electrolyte on Ammonia Volatility at 80°C from Flow Cell Data... 

The volatility of ammonia can be significantely affected by high concentrations of dissolved ions in the liquid phase. In sodium acetate the volatility increases by a factor of 1.9 at 25 wt % of salt. In sodium hydroxide the volatility is enhanced to a lesser degree with an increase of 1.25 at 22.5 wt % NaOH. Both electrolytes produce ions with only one electronic charge, but their effects on the volatility of ammonia are significantly different. Thus the effects of various ionic components must be studied individually in order to determine their effect on the volatility of NH3. 

At the low ionic concentrations encountered in sour water strippers, the effect of dissolved ions is probably small. Thus at a 1% concentration of sodium acetate the volatility of ammonia only increases about 2.5% due to the salt. This is within the prediction accuracy of the ammonia volatility data and no correction is therefore required. However significant ionic effects could exist in the condenser where high concentrations of the ionic components could exist. 

Ammonia partial pressure data have been determined at concentrations from 10 ppm up to 5 wt % in water at temperatures of 80 and 120°C. The pH of NH3-H2S-CO2-H2O mixtures have also been measured at 25 and 80°C. Also the effects of sodium hydroxide and sodium acetate on ammonia volatility data have been measured at 80°C. Various conclusions made from the data are as follows. 

The volatility of ammonia can be significantly affected by high concentrations of dissolved ions in the liquid phase. Unfortunately the effect varies depending on the types of ions in solution. Sodium acetate produces a... 

One has to emphasize that MS also is associated with several drawbacks when it comes to bioactivity screening. First of all, the optimum, native conditions for bioactivity screening (pH 7.2, addition of 150 mM sodium chloride) are entirely incompatible with optimum conditions for MS detection which, for ESI-MS, typically require acidic pH values and the presence of organic modifiers to enhance ionization properties of the analytes. Assay development for MS-based assays therefore mainly requires the testing of different assay conditions, particularly the replacement of nonvolatile buffers with MS-compatible volatile buffers. Furthermore, it is essential to monitor ion suppression effects, for example, by the... 

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