the epoxidation of olefins with tetra n-butylammonium periodate, n-bu4/nio4, is catalyzed by six different tetrakis (4-substituted phenyl) porphyrinatomanganese(iii) acetate, mn(t4-xpp)oac, complexes in the presence of imidazole as an axial ligand with low to high yields and complete selectivity at room temperature. while the electronic effects of the highly electron-withdrawing no2 substituent...

Adequate iodide supply and metabolism are essential for thyroid hormones synthesis. In thyrocytes, iodide uptake is mediated by the sodium-iodide symporter, but several proteins appear to be involved in iodide efflux. Previous studies demonstrated that pendrin is able to mediate apical efflux of iodide in thyrocytes. Acute iodide excess transiently impairs thyroid hormone synthesis, a phenomeno...

A fiber-type heterostructured scintillator based on bismuth germanate (Bi 4 Ge 3 O 12 ) functionalized with the 2D-perovskite butylammonium lead bromide ((BA) 2 PbBr has been fabricated, and its scintillation performance analyzed toward use for fast timing applications such as time-of-flight Positron Emission Tomography. The pixel shows energy sharing between matrix filler component, confirming...

a simple, mild and practical procedure has been developed for the synthesis of symmetrical and unsymmetrical ethers by using dmso, tbai in the presence of k2co3. we extended the utility of  potassium carbonate as an efficient base for the preparation of ethers. a wide range of alkyl aryl and dialkyl ethers are synthesized from treatment of aliphatic alcohols and phenols with various alkyl halid...

a sensitive and selective extraction - spectrophotometric method for the determination of trace amounts of palladium is reported. the method is based on quantitative extraction of brownish tetrabutylammoium tetraiodopalladium (ii) ion pair into a small valume of chloroform at ph 1.3-12.0, followed by spectrophotometric measurements. the beer's law is obeyed over the range 0.02-1.09 mgml-1 at 44...

Iodide (I(-))-accumulating bacteria were isolated from marine sediment by an autoradiographic method with radioactive (125)I(-). When they were grown in a liquid medium containing 0.1 microM iodide, 79 to 89% of the iodide was removed from the medium, and a corresponding amount of iodide was detected in the cells. Phylogenetic analysis based on 16S rRNA gene sequences indicated that iodide-accu...

Although it is beyond doubt that mammary cells accumulate iodide via a Na+-dependent transport mechanism, it is not clear if this is the only pathway for iodide transport in mammary tissue. In view of this, experiments were designed to test for the presence of an anion-exchange pathway which could mediate the transport of iodide into mammary cells; thus, the effect of external iodide on sulfate...