Quantitative evaluation of 28 mineral elements by inductively coupled plasma/mass spectrometry and its application in source identification of Indian opium

An analytical method based on inductively coupled plasma/mass spectrometry (ICP/MS) was developed for the determination of 28 mineral elements (Cr, Mn, Co, Ni, Cu, Zn, Ga, Sr, Cd, Ag, Ba, Pb, Bi Y, La, Ce, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) in Indian opium samples. The detection limits were found to be in the range of 0.0008-0.45 ng/mL. The recoveries of spiked samples for each element were found to be in the range of 83-106%, with a precision of less than 9%. A total of 124 opium samples from India were analyzed for the distribution pattern of the 28 mineral elements. Quantitative elemental data were subjected to chemometric analysis in order to determine an optimal classifier to evaluate the source of Indian opium. The study indicated that mineral elements might not be the suitable discriminators for the discrimination of licit opium-growing divisions of India. However, the methodology developed and the analytical data on elemental profile may find important forensic application in discriminating Indian opium with that of licit and illicit opium originating from different geographical regions of world.     

Electro-initiated polymerization of acrylonitrile in aqueous acetic acid containing Mn(OAc)2·4H2O and CNCH2COOH

The electro-initiated polymerization of acrylonitrile initiated by the anodic oxidation of an aqueous acid solution (80% HOAc + 20% H₂O) containing Mn(OAc)₂ · 4H₂O/CNCH₂COOH has been investigated in the 30–40°C temperature range. The kinetics and mechanism of the process has been investigated as a function of variables and a suitable mechanism proposed. From the experimental observations the rate of polymerization is seen to be proportional to [An]^1.5I^0.5[Mn⁺²]^0.5 and [CAA]^0.5. The rate of polymerization gradually decreases at a higher applied current. The rate was independent of [CAA]^0.5. The rate of polymerization gradually decreases at a higher applied current. The rate was independent of CAA at high concentration. The average degrees of polymerization (P _n) increases with increasing AN and decreasing [CAA], [Mn⁺²] and applied current, I. The initiation is due to the anodic oxidation of Mn⁺²–CNCH₂COOH complex. Both the initiation of polymerization by the primary radical, viz., CN? C?? COOH as well as the oxidation of the primary radical at the electrode are equally significant reactions and neither can be neglected in comparison with the other. Predominant mutual termination accounts for all the observed data.     

Preparation and properties of azopolyimides-I

A new class of aromatic and heterocyclic polyimides were synthesized from benzothiazoleamines benzidine, 4,4′-diaminodiphenyl ethane and 4,4′-diamino diphenyl sulfone with 4,4′-azodipthalic anhydride and/or pyromellitic dianhydride. The synthesis involved the reaction of the dianhydride with the respective diamine to yield an intermediate, soluble, open chain precursor polymer, the polyamic acid, which on cyclodehydration yielded the less soluble, heat resistant polyimides. All these polyimides were characterized by IR and NMR. Solubility, density, viscosity, and thermal stability of these polymers were also studied.     

Polymer-supported palladium and platinum species as hydrogenation catalysts

The synthesis of new hydrogel copolymers and their use for anchoring Pd and Pt species is described. The supported catalysts are effective for the reduction of alkenes, dienes, alkynes, and nitroaromatics under mild conditions. The catalysts have been characterized by chemical analysis, particle size measurement, IR, TGA, and x-ray photoelectron spectra. Relative reactivities and the effects of substrate structure, solvents, catalyst loading, particle size of the catalysts, and partial pressure of hydrogen have been determined. The kinetics of hydrogenation have been analyzed using concepts useful under slurry reaction conditions. The recycling efficiencies of the catalysts and product analysis to establish selectivities have been assessed. © 1992 John Wiley & Sons, Inc.     

Alternating copolymerisations of dioxaphospholane and dioxaphosphorinane with γ-butyrolactone and ethylene oxide

Alternating copolymers containing phosphorus were prepared from 2-phenyl-1,3,2-dioxaphospholane, 2-phenyl-4-oxo-5,6-benzo-1,3,2-dioxaphosphorinane with ethylene oxide and γ-butyrolactone. The polymerisations took place without added catalyst. The copolymers were characterised by i.r. and NMR spectroscopy, viscosity measurements and phosphorus estimation. Key intermediates responsible for initiation and propagation of the copolymerisations were isolated and the mechanism of copolymerisation is discussed.     

Crystal and molecular structure of tetra-n-butylammoniumbis(stilbenedithiolato)-nickelate(III)

The crystal and molecular structure of the title compound, C₄₄H₅₆NS₄Ni, are reported. Crystals are triclinic, space groupP¯1 (No. 2) withZ=2 in a unit cell of dimensionsa=8.874(2) Å,b=9.549(5) Å,c=26.025(7) Å,=97.22(3)°,=95.06(2)°, and=98.75(3)°. The structure was solved by Patterson and Fourier methods and refined by full-matrix least squares toR=0.062 for 2910 unique diffractometer data. The metal atom of the anion has an approximate square-planar configuration and the nitrogen atom of the cation an approximate tetrahedral configuration. The anions as well as the cations are well separated, the closest NiNi and NN approaches being the lattice repeat of 8.874(2) Å.