Strontium concentration

Figure 1.4b. Strontium concentration in raw and cooked foods (as described in fig. 1.4a).

Aloy, A. S., Iskhakova, O. A., Koltsova, T. I. Trofimenko, A. V. 1998. Glass waste form performance for disposal of the cesium and strontium concentrate resulting from the partitioning of HLW. Materials Research Society Symposium Proceedings, 506, 901-906. 

Figure 7.2 shows the activation energy as a function of strontium concentration x, deduced from the results of Fig. 7.1. The linear behaviour followed by a tail is very similar to the plot of e2 in Fig. 5.2. The reason for the tail...

XRF analyses of Silver Lake and Sycan Marsh obsidian source samples suggested the possibility that the two sources could be differentiated based on small differences in strontium concentrations. However, when the standard error for strontium was taken into account, both groups overlapped at one standard deviation. Because of higher instrumental detection limits for strontium, NAA could not discriminate between the two sources. LA-ICP-MS analyses were conducted to determine if the sensitivity and precision of this analytical technique was sufficient to confirm the existence of the two compositional... 

Inspection of individual test runs showed that the strontium spike, corresponding to 3xl0 3M total strontium, dissolved entirely when HEDTA or EDTA concentrations were 0.1M or 0.05M, respectively. However, in the presence of 10 5M or lower HEDTA or EDTA concentrations, strontium was at saturation with concentrations of about 4xl0 5M (-0.17 Ci 90Sr/L in Hanford HLW). Strontium concentrations in Hanford HLW, as shown in Table HI, are about 0.004 Ci "Sr/L and probably not solubility limited. 

Figure 7.33. Geochemistry of the Devonshire, Bermuda groundwater lens. (A) Log of partial pressure of CO2 (PCO2X (B) strontium concentration in ppm, (C) calcium and (D) magnesium derived from the rock because of diagenesis in the meteoric realm. (After Plummer et al., 1976.)...

Sowden EM, Pirie A. 1958. Barium and strontium concentrations in eye tissue. Biochem J 70 716-717. 

Table I. Barium, Calcium, and Strontium Concentrations from Recently Killed Specimens of Fur Seal and Deer...

Figure 5. (top Strontium concentration vs. age for terrestrial mammal hone samples from the Marmes Rockshelter, Each point represents a single sample. The error bars represent the standard deviation based on the statistics of radioactive decay. 

The present method of analysis offers several distinct advantages. The first of these is speed calcium, barium, and strontium concentrations are determined simultaneously in a short irradiation, and analysis of up to seven samples can be completed within hours. Neutron activation analysis is highly sensitive to the elements of interest compared with other methods such as x-ray fluorescence and atomic absorption techniques. Additionally, the required sample size is small (10-20 mg), thus resulting in little alteration of archaeological specimens. 

We have analyzed over 350 samples of recent and archaeological bone and have found patterned relationships in the barium and strontium concentrations. Provided that suitable caution is exercised to exclude... 

Ophel, I.L., Fraser, C.C., and Judd, J.M. Strontium concentration factors in biota and bottom sediments of a fresh water lake, p. 509-530, Intern 1 S3nnp. Radioecology Applied to the Protection of Man and His Environment, Vol. 1/2, Rome, Italy, Sept. 7, 1971, Eur-4800, 1972. 

The additional presence of 50-100 mg/L of strontium in the ammonium stripping solution remains one of the major problems in applying clinoptilolite for the recovery of strontium. Selective separation of strontium and calcium before precipitating SrCOj as a pure final product also remains a sizable problem. A possible solution to this problem may be provided by applying cascade schemes [15]. Such treatment of strontium concentrate could include columns with fixed beds of selective and auxiliary sorbents, e.g., [KU-2—Cli] [KU-2—Cli] —> etc., where brack-... 

Figure 3. Resistance vs. temperature, normalized to 50 K, showing the superconducting transition for six values of strontium concentration, x. As x deviates from the optimum value of 0.15, the transition decreases and broadens. Vertical line is drawn at 40 K.

Auxiliary electrodes are also required if a cation-conducting electrolyte is used for measuring a metal which is different from the ion that is mobile in the electrolyte. For example, the use of Na [3 alumina for the measurement of antimony in zinc requires the use of a NaSbO3 auxiliary electrode [221]. Sodium [3 alumina has also been used for measuring magnesium and strontium concentrations in molten aluminum [222]. In this case, the auxiliary electrode forms in situ by an exchange reaction between... 

The solubility of SrSe04(cr) in water has been determined over the temperature interval 273 to 373 K. Crystalline strontium selenate was prepared by mixing stoichiometric amounts of strontium nitrate and selenic acid. Under the light microscope the crystals appear as very thin needles. The strontium concentration in saturated solution was obtained by polarographic (half-wave potential at -2.1 V) and gravimetric measurements. Both methods gave concordant results, Table A-18. 

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