FeO@PDA@PANI core-shell nanocomposites as a new adsorbent for simultaneous preconcentration of Tartrazine and Sunset Yellow by ultrasonic-assisted dispersive micro solid-phase extraction.

In this research, novel magnetic FeO@PDA@PANI core-shell nanoparticles were designed and fabricated as an efficient adsorbent in the service of ultrasound-assisted dispersive micro-solid phase extraction for simultaneous preconcentration of Sunset Yellow (SY) and Tartrazine (Tar) before UV-Vis spectrophotometric detection. This adsorbent was fully characterized by Fourier Transform Infrared (FT-IR) spectroscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Energy Dispersive X-ray (EDX) analysis. To overcome the spectral overlapping of SY and Tar dyes, the derivative spectrophotometric method was successfully used for the simultaneous detection of dyes in their binary solutions.

Application of ultrasonic-assisted inclusion complex formation with α-cyclodextrin for simultaneous spectrophotometric determination of gallic acid and vanillic acids in fruit samples.

There are various methodologies to generate second-order data. Spectrophotometric method owing to its high sensitivity continues to be of wide interest to analytical chemists. Spectra recording at different interval time while the reaction is proceeded, or at different pHs, or at different concentrations of complexing agent are examples of strategies by which one can generate second-order data by the spectrophotometric method.

Comparison of halogen bonds in M-X⋯N contacts (M = C, Si, Ge and X = Cl, Br).

The halogen bonds (XB) formed between some Si-X- and Ge-X- (X is Cl and Br) containing molecules and NCH (as a Lewis base) have been investigated and compared with C-X⋯N halogen bond. Although, in all cases, the existence of a positive electrostatic potential (σ-hole) along the extension of M-X was responsible for halogen bond formation, multipole expansion of electrostatic potential reveals that these positive potentials originate from different atomic multipole moments. Indeed, in addition to the monopole moment of M atoms, the quadrupole moment of X in C-X molecules, the dipole moment of the halogen in Si-X molecules and both the dipole and quadrupole moments of X in Ge-X molecules are mainly responsible for the existence of the σ-hole along the extension of the M-X bond.

An ortho-rhom-bic polymorph of 2-(1,3-benzothia-zol-2-yl)-6-eth-oxy-phenol.

In the title mol-ecule, C(15)H(13)NO(2)S, an intra-molecular O-H⋯N hydrogen bond forms an S(6) ring motif. The benzothia-zole ring system and the benzene ring form a dihedral angle of 8.9 (3) Å.