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This paper describes the study of the extraction of Zr and Hf in nitric and hydrochloric media by solvent extraction technique using different types of extractants. The effect of the extractants DEHPA, IONQUEST®801 and CYANEX®272, TBP, CYANEX®923, PRIMENE ® JTM, ALAMINE ® 336 and ALIQUAT®336 was investigated. For acid extractants in both nitric and hydrochloric media, a high degree of extraction was observed, although they had low selectivity in separating the metals. For the acid extractants also, it was not possible to strip the metals from the organic phase through acid solutions. In this case, a stripping solution with very high acidity would be required, and this is not viable. When the basic extractants were used, no metal extraction was observed under the conditions investigated, indicating no extractable anionic species in either media. The optimum zirconium/hafnium separation was achieved using an acidity of 7.0 mol•L −1 , nitrate concentration of 9.2 mol•L −1 and 1.5 mol•L −1 of TBP. In these conditions, a separation factor of 12.6 was obtained.

Purpose: The preoperative diagnosis of axillary status by means of Fine Needle Aspiration (FNA) guided by ultrasound is a method to obtain information on axillary lymph node status allowing decision about management of the axilla. This is a cross-sectional study aiming to analyze the use of ultrasound guided FNA for axillary lymph nodes and to determine the usefulness of this method in the preoperative staging of breast cancer patients candidates for sentinel lymph node biopsy (SNB).Methods: Ultrasound guided FNA were performed in 41 patients who had presented abnormal alterations in axillary lymph nodes. Patients with malignant cytology avoided SNB and were submitted directly to axillary lymph node dissection (ALND), patients with negative cytology held SNB. The histological findings were compared with the results of ultrasound guided FNA. Results:In evaluating FNA cytology, 18 (43.90%) patients presented cytology compatible with malignancy and 23 (56.10%) were benign. The axillary ultrasound guided FNA demonstrated a sensitivity of 81.8%, specificity of 100%, positive predictive value (PPV) of 100%, negative predictive value (NPV) of 82.6% and 90,2% of accuracy. Conclusion:The data demonstrate that the FNA is an effective procedure in preoperative assessment in patients with breast cancer.

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