Flame Photometric Determination of Manganese

were each run in quadruplicate on two consecutive days. The results are shown in Table 11.While the standard deviation for both wire bar and anode copper calculated on eight runs is extremely low, it is still more gratifying to note that the averages of quadruplicate runs obtained on two different days are practically identical.Interferences. Selenium, tellurium, arsenic, and antimony would all interfere in the sulfur analysis of copper by the combustion-iodate titration method if introduced into the reaction vessel. This is why no attempt was ever made to determine sulfur in anode or blister copper by the combustion-iodate method. These materials were always analyzed for sulfur by the long gravimetric Precision. FIa me Photometricmethod as barium sulfate. It is, therefore, obvious that considerable saving in time would be realized if the pararosaniline method were applicable to the analysis of sulfur in anode and blister copper. To establish the possible interferences, increasing amounts of selenium, tellurium, arsenic, and antimony were added to synthetic solutions containing 25 pg. of sulfur and the color was developed in accordance with the standard procedure. The results obtained are shown in Table 111. The data indicate clearly that none of the four impurities considered, present in concentrations up to 10 times that of sulfur, has any effect whatsoever on the precision and accuracy of sulfur analysis. RESULTS

Section: Nalytical Applications Of 2-mentioning

confidence: 99%

“…"No change 6. Masking mixture consisting of equal parts by volume of 2M tartaric acid and 2M sodium fluoride.…”

mentioning

confidence: 99%

Flame Photometric Determination of Manganese in Copper and Steel Alloys.

Johnson¹,

Lott²

1963

“…It is beyond the scope of this paper to discuss the determination of each of the constitutents in detail, but it is appropriate to draw attention to several important points. The direct nebulization of dissolved steel samples has been previously employed for the determination of Cr and Mn as major constitutents (>0.5 wt %) in steels and slags (31,32). For the AAS determination of Al, Konig et al (9) have reported that reference "blank" solutions should have approximately the same Fe content as the test solution.…”

Section: Resultsmentioning

confidence: 99%

Flame emission spectrometric determination of aluminum, cobalt, chromium, copper, manganese, niobium, and vanadium in low and high alloy steel

Fassel¹,

Slack²,

Kniseley³

1971

In this case O (-J means that the additional term ne-\r0 -z) glected is of order 1 /(r0 -z). From this equation, it can be seen that if r" is large in comparison with the time interval of the heat input P(z), then Equation 53 can be approximated by F(t,t0) = In -^P(z),dz (54) and again the integral of the temperature deviation at any radius e is approximately proportional to the heat flux into the sink. This equation also indicates that the constant of proportionality is dependent upon r0, the time interval of measurement.Thus, when a calibration experiment is followed by an actual measurement, the time intervals in both experiments must be approximately the same, and this time interval must be larger than that of both the heat pulses. This problem should be considered when a quick reaction is used as a calibration for a slow reaction. In this case, the tendency is to stop the calibration experiment before the proper t0 is reached.Calorimeter Usage. In the theory developed previously, the heat sink was assumed to be infinite; in actual usage this sink is large but finite. For the infinite approximation to be true, two conditions must be satisfied. The total heat expected during an experiment must not make a significant change in the steady state temperature of the heat sink; the outside edge of the heat sink must be far away from the cavity such that the temperature change at this edge is practically zero.To determine if these conditions are satisfied, the analysis should be carried out for each particular geometry and heat sink materials.If the calorimeter is to be calibrated by one experiment and used in others, care must be taken to be sure that the same heat flux distribution over the surface of the cavity results during both experiments. Thus approximately the same type reaction cell should be used in the cavity during both experiments. This difficulty may be circumvented somewhat by placing thermocouples such that they totally surround the cavity, thus removing angular dependencies. These difficulties plus others arising from measurement techniques apparently have been overcome because these calorimeters give good results.

“…All emission measurements reported in this study were made by the method of background correction (5,6) and represent net emissions unless othern-ise noted. They were obtained by making measurements a t two wave lengths, one a t the wave length of the emission peak of t'he element under study, thc second a t the closest neighboring wave length that gives, while the element being det'ermined is being aspirated, an emission approaching that given by distilled water.…”

Section: Instrument and Emissionmentioning

confidence: 99%

Releasing Effects in Flame Photometry. Determination of Calcium

Dinnin¹

1960

Strontium, lanthanum, neodymium, samarium, and yttrium completely release the flame emission of calcium from the depressive effects of sulfate, phosphate, and alumínate. Magnesium, beryllium, barium, and scandium release most of the calcium emission.These cations, when present in high concentration, preferentially form compounds with the depressing anions when the solution is evaporated rapidly in the flame. The mechanism of the interference and releasing effects is