A novel method for the determination of iodide in table salt by X-ray fluorescence

A novel HI generation technique was developed and evaluated for the determination of iodide in table salt. HI was generated from the samples by the addition of concentrated sulfuric acid and adsorbed onto an ion-exchange resin loaded paper disk. The disk was then measured by X-ray fluorescence. The method compared favorably to the cellulose pellet technique, being more sensitive and reproducible and requiring less time per analysis. The method was applied to six samples of table salt and one of sea salt.     

Cubic graphs on twelve vertices and the line graph of a finite affine plane

It is shown by Rao and Rao that certain geometric properties characterize the line graph of a BIB design with parameters b, v, r, k, 1, provided r - 2k + 1 < 0. If r = k + 1, and $\text{k \#\&62; 2}$, a characterization of the line graph of a finite affine plane is obtained. If r - 2k + 1 = 0, the only possible value for k is 2 and consequently r = k + 1 resulting in the case of the line graph of a finite affine plane. It is shown here that if r = k + 1 and k = 2, there are exactly seven other non-isomorphic graphs with those properties which are not the line graph of a finite affine plane and these are the only cubic graphs on twelve vertices with no quadrilaterals.     

Crystal structure of methylgermanium triiodide

The structure of MeGeI₃ is orthorhombic with space groupPnma,a=6.374(3),b=10.412(4),c=12.683(4) Å, andz=4. It has been solved by direct methods and refined by full-matrix least-squares techniques to a conventionalR factor of 0.0791 for 653 unique reflections. The crystal structure contains discrete molecules with mirror symmetry which are separated by normal van der Waals distances. The mean Ge-I distance is 2.500(2) Å.     

Pyrazole‐4‐carboxylic Acids from Vanadium‐catalyzed Chemical Transformation of Pyrazole‐4‐carbaldehydes

The conversion of aldehydes into carboxylic acids using oxidizing agents is a common protocol in transformation chemistry. An efficient oxidation strategy of transformation of pyrazole‐4‐aldehydes to the corresponding acids using vanadium catalysts in the presence of 30% H₂O₂ as an oxidant is described. The catalytic technology was successfully applied to a range of various 4‐formylpyrazoles, and plausible mechanism is also discussed.     

Facile and efficient synthesis of chiral sulfoxide esters: Versatile tool in asymmetric synthesis

Facile and efficient synthesis of sulfoxide esters using menthols as chiral auxiliary is described. Phenylthio/benzylthio/naphthylthioacetic esters act as an efficient substrate for chiral sulfoxides via oxidation in one step. The structural and stereochemical aspects of target product were established on the basis of various spectroscopic studies, namely FT-IR, NMR (¹H NMR and ¹³C NMR) and elemental analysis. This method is simple, fast, convenient and very efficient.