Sulfate ratio

Fig.2. Expectation time of efflorescence of (NH4)2S04 and H2SO4 solution, log(x(min)) according to ammonium-sulfate ratio (ASR) at Dpm = l, m and 25°C.

Sulfate ratio control, in Claus conversion chemistry, 23 611—612 Sulfate-reducing bacteria, 23 569, 577 Sulfate-reducing conditions defined, 3 757t... 

Our first experience was that as the drag out tanks were added to the chrome tank our chrome metal went from 28 oz up to 36 oz. We had to adjust our sulfate ratio on a daily basis. This is the catalist that makes a chromium bath work. This was as it had been before, but more acute. We did not add any new chromic acid to the tank until March,1987. At that time we started to have plating problems. 

A simple calculation of the lifetime of MSA in cloud water can be made using model estimates of the free radical chemistry of cloud droplets. The OH concentration in cloud water is a complex function of both the gas and aqueous phase chemistry and the dynamics of gas/liquid exchange. A recent model (21) estimated cloudwater OH concentration as 2-6 x 10 M for droplets of 5 -30/im radius. Using the rate constant measured here (4.7 x 107 M 1 s 1), this yields a lifetime of 1.2 3.5 hours. Considering that the lifetime of a nonraining cloud is on the order of a few minutes to an hour, some fraction of the MSA present could react with OH, presumably being converted to sulfate. While such a process may lower the concentratron of MSA in the droplet, it would only have a minor effect on the cloudwater sulfate levels because of the typically low MSA non-sea-saIt sulfate ratio in the aerosol entering the cloud. 

Washout ratios for aerosol S04= and for total NO3" (HNO3 + aerosol NC ") are presented in Table 3. These washout ratios presuppose, in accordance with Barrie s treatment (18), that SO2 does not contribute to the rain SO and that both HNO3 and aerosol NO3" contribute to the rain NO3. Accordingly, the sulfate ratios are upper limits on W and the NC " ratios reported are close to, and only slightly less than, WNQ for HNO3 alone since HNO3 is highly soluble and dominates the total NC ". Thus from Table 3,... 

Generally speaking, conclusions regarding stereoselective sulfation in vivo are difficult to draw, because of competition between (stereoselective) glucuronidation and sulfation of the same substrates. Stereoselective sulfation of 4 -hydroxypiopranol enantiomers was demonstrated in vitro in hepatic tissue of various species (Christ and Walle, 1985). Enantiomeric (-/-l-)-4 -hydroxypropranolol sulfate ratios varied from 1.07 in the rat and... 

Fig. 15. TEM of tabular crystals from the desmid M. thomasiana showing changes in shape on increasing the metal sulfate ratio in the external environment of a cell culture. Rounded crystals are obtained as strontium substitutes into the barite lattice. Bar = 0.5 /xm.

A nominal 40% of the pyritic sulfur remains with the coal as elemental sulfur. All indications are that the sulfur-to-sulfate ratio is constant. 

The effect of sulfite to sulfate ratio (oxidation fraction on adipic acid coprecipitation. 

The ability of sulfate-reducing bacteria to methylate inorganic mercury depends on sulfide-to-sulfate ratios sulfate concentrations less than 1 mg L starves sulfate-reducing bacteria and thus inhibits methylation. Sulfate concentration greater than 20 mg L will result in excess sulfide production, which will also inhibit mercury methylation. 

The upper portion of Table III gives the sulfate data for the midwestern site and the lower portion presents the data for the eastern sites. The dotted lines connect those sites for which it is considered most appropriate to calculate ratios between the recent and the older concentrations. The right hand column provides additional data for comparison to the middle column. The same format is used in Table IV. The basic feature to note in the tables is that the sulfate ratios are near one, while those for nitrate are greater than one. These trends will now be compared to the source emissions trends. 

JACOBSON The interpretation that the high sulfate to nitrate ratio increased growth is indeed more reasonable than suggesting that the high nitrate to sulfate ratio treatment depressed growth. 

Other authors have confirmed the radioactive sulfate incorporation data (Green and Robinson, 1960 Bakke and CoRNATZER, 1961 Davison and Gregson, 1962 Kataoka, 1962 and Burton, unpublished data). While Burton (unpublished data) has obtained results consistent with those of Rad in s for the persistence of radioactive sulfate in the cerebroside sulfate fraction. Burton s experiments indicate the same rate of loss of radioactivity due to in the carbohydrate moieties of cerebroside and cerebroside sulfate whereas Radin et al. found a retension of as well as Hauser (1964) and others (Bakke and Cornatzer, 1961, Davison and Gregson, 1962) have observed that the cerebroside cerebroside sulfate ratio in brain tissue appears to remain constant even though these lipids accumulate with age. Thus Hauser (1964) found ratios of 3 in 20 day-old rats and 4 in adult animals. Further experiments need to be carried out to determine... 

Benzidine methods make use of the very low solubility of benzidine sulfate which can be isolated and titrated as an add as in the method of Rosenheim and Drummond (79), or determined by means of a color reaction such as that with hydrt en peroxide and ferric chloride (91), or sodium fi-naphthoquinone-4-sulfonate(59),orbydiazotizationandcoupling(33,55,72). The colorimetric methods are claimed to be very sensitive. The benzidine method provides a rapid method for estimating ethereal sulfate but since, like the Folin (43) method, it is a difference method it becomes less reliable as the inorganic. ethereal sulfate ratio increases. The precipitation of benzidine sulfate by the original method, especially from hydrolyzed urines, may occasionally be capricious, even to the extent that less benzidine sulfate is precipitated from hydrolyzed urine than from unhydrolyzed urine. This difficulty can be largely overcome by preliminary removal of phosphates and precipitation under conditions recommended by Fiske (42). Under experimental conditions dietary control may serve to ensure that the excretion of phosphate is so low as not to interfere with precipitation of benzidine sulfate (e. g.. Maw (63)). 

This method is reliable if the ratio of inorganic ethereal sulfate does not exceed 5. Sulfite does not interfere with the determination. If the inorganic ethereal sulfate ratio exceeds 5, inorganic sulfate can be determined by this method and ethereal sulfate as described below. 

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