Salah A . M . Khalifa

The extraction of cobalt(II) by chloroform solutions of the crown ethers (CE) 12C4, I5C5, 18C6, Dbl8C6, Dchl8C6 or Dch24C8 from aqueous perchlorate medium was investigated. Slope analysis of the experimental data suggested that the extraction of Co(II) by these CEs takes place through ion-pair formation, and that the chemical formula of the main extracted species is Co(OH)(+)ClO(-)(4).CE. The magnitudes of the extraction constants are in the sequence 18C6 > Dch18C6 > Dch24C8 > Db18C6 > 15C5 > 12C4, which is discussed in terms of the correspondence between the CE cavity size and the ionic radius of cobalt(II).

The clinical features of acute Brucella arthritis were reported in a prospective study of 58 patients (29 male, 29 female). Polyarthritis occurred in 33, was migratory in ten, additive in 23 and symmetrical in ten. Monoarthritis of knee or hip joints occurred in ten patients, whilst the spine alone was involved in 15. Hip and spinal involvement was more destructive than peripheral joint involvement. Hotness, redness and joint effusions were not prominent features. Tissue-typing did not show any association with Brucella arthritis. Treatment with various antimicrobials was followed by recovery, but the relapse rate was lowest with combined tetracycline and streptomycin. Brucella arthritis is frequently seen in Iraq, and dairy products prepared locally from unpasteurized milk should be controlled by local health authorities.

The effect of some environmental ligands and certain fertilizers on the complexation of strontium with humic acid wasinvestigated colorimetrically and radiometrically. The results indicate that Na2-EDTA, Na3-citrate and NaCl compete to complex strontium in solution with the sequence: chloride 3-phosphate has the reverse behavior. In the case of nitrogen containing fertilizers, the results show that urea, Mg-ammonium nitrate and ammonium nitrate increase the availability of strontium to plants and microorganisms.

Selective efficient method have been for separation of palladium by strong basic anion exchangers IRA-410 and IRA-900 from intermediate radioactive nitrate medium. The different conditions for exchange behaviour of palladium from [ILLW] solutions containing numbre of elements were investigated by batch technique. Selective recovery of palladium from the [ILLW] solution was achieved using column technique. The elution of palladium was

... N. EL-SAID, AS MEKHAEL, SM KHALIFA. HF ALY Hot Laboratories Centre. Atomic Energy Authority, Post Code 13759. Cairo (Egypt) ... The distribution coefficient was calculated as C - C o V Kd = X C m Column Application: A chromatographic double jaket column was used in ...