Concentrations of rare elements in soil and clover, taken from a refuse reclaimed site (Y-area) and a control area (T-area), were determined by radioactivation analysis. Concentrations of many rare elements (fourteen out of twenty six elements) in Y-area soil were larger than those in the control area. However, the magnitude of each element was not judged to be large enough to show the environmental contamination related to human activities. Concentrations of rare earth elements in clover were very low. Therefore these elements are assumed to be stable in insoluble form in soil and be hardly taken up by the root of clover. Homologues of essential elements showed higher concentrations in clover. This suggests that the homologues, which are clearly related to human activities, may become promising indications for monitoring environmental pollution.
Distribution coefficients (Kd) of nuclides, which are defined as the ratio of the adsorbed concentration to the solution concentration, are important in predicting nuclide migration in the subsurface environment. This study was undertaken to construct an effective method of determining the most pertinent Kd value for simulating in situ distribution phenomena between the solid and liquid phases, by using background stable isotopes. This paper describes the applicability of this method to Sr by carrying out a batch Sr adsorption experiment where stable Sr coexisted with the radioactive isotope, 85Sr, and by comparing the concentration distribution ratio of the background stable Sr with the Kd value obtained by the batch experiment. The results showed that the Kd of85Sr (Kd85) agreed well with the Kd of the coexisting stable Sr (Kds) and that the two values decreased with an increase in the concentration of the stable Sr, when sand was used as an adsorbent. In addition, the Kd85 corresponded to the ratio of the exchangeable solid-phase concentration of background stable Sr to the concentration of the background stable Sr in groundwater when the concentration of the coexisting stable Sr approached the background level. On the other hand, when powdered rock samples were used, the Kd85 did not agree with the Kds and the concentration distribution ratio of the background stable Sr was greater than the Kd85. This discrepancy might be due to the disequilibrium resulting from grinding the rock matrices. This suggests that measurement of the background stable Sr distribution ratio between the solid and liquid phases can be an effective method of estimating the Kd of radioactive Sr when the groundwater is in satisfactory contact with the adsorption medium.
Acetanilide, propionanilide, and isobutyranilide were tritiated at the ortho positions with very high regioselectivity by heating with HTO in the presence of RhCl3⋅3H2O in N, Ndimethylformamide (DMF) . In this reaction for pivalanilide the specific activity alone was determined, because attempts to establish the regioselectivity were unsuccessful. The extent of tritium incorporation decreased with increasing bulkiness of the alkyl groups. Only slight tritium was introduced by the same reaction for tri fluoroacetanilide, which would probably be attributed to a strong electron-attracting property of the tri fluoromethyl group. The above findings give support to the previous suggestion that the present isotope exchange reaction proceeds via an initial coor dination of the nitrogen atom of anilides to the rhodium (III) chloride trihydrate catalyst.
The distribution of a new myocardial fatty acid metabolic agent123I-BMIPP was compared in 6 of each patients with hypertrophic myocardium (4 cases of hypertensive heart disease and 2 of hypertrophic cardiomyopathy) and dilated myocardium (4 of dilated type of valvular heart disease and 2 of dilated cardiomyopathy) with that of201Tl. Mismatched regional myocardial uptake between123I-BMIPP and201Tl SPECT was observed in all of the hypertrophic myocardium, however no but one in the dilated myocardium. Relative increase or decrease in regional BMIPP from the images of 20 min and to those of 4 h was observed in 3 cases of the hypertrophic myocardium. FDGPET was performed in 2 cases of the hyper-trophic myocardium. The distribution of FDG was different from neither those of BMIPP nor Ti in a hypertrophic cardiomyopathy case with the reversed distribution of BMIPP and Tl. Although more investigations are necessary, we concluded that123I-BMIPP is a promising radiopharmaceutical for evaluating myocardial fatty acid metabolism in hypertrophic myocardium.