Flow injection potentiometric determination of pancuronium bromide in pharmaceutical preparation and urine samples using modified carbon paste electrodes

Carbon paste electrodes for pancuronium bromide was prepared based on ion association complexes of pancuronium bromide with sodium tetraphenylborate (NaTPB) or ammonium reineckate using dibutyl phthalate as solvent mediator and tetradodecylammonium tetrakis-(4-chlorophenyl)borate (ETH 500) as lipophilic additive. The sensors showed a near-Nernstian slope of 28.1 mV concentration decade(-1) at 25°C within the concentration range 6.31×10(-6)-1.00×10(-2) M in case of pancuronium-tetraphenylborate electrode and 26.6 mV concentration decade(-1) in the concentration range 5.66×10(-5)-1.00×10(-2) M in case of pancuronium-reineckate electrode. The sensors were successfully applied for the potentiometric determination of pancuronium bromide in pharmaceutical preparation and biological fluids in batch and flow injection conditions.     

Self-assembly of dendronized perylene bisimides into complex helical columns

The synthesis of perylene 3,4:9,10-tetracarboxylic acid bisimides (PBIs) dendronized with first-generation dendrons containing 0 to 4 methylenic units (m) between the imide group and the dendron, (3,4,5)12G1-m-PBI, is reported. Structural analysis of their self-organized arrays by DSC, X-ray diffraction, molecular modeling, and solid-state (1)H NMR was carried out on oriented samples with heating and cooling rates of 20 to 0.2 °C/min. At high temperature, (3,4,5)12G1-m-PBI self-assemble into 2D-hexagonal columnar phases with intracolumnar order. At low temperature, they form orthorhombic (m = 0, 2, 3, 4) and monoclinic (m = 1) columnar arrays with 3D periodicity. The orthorhombic phase has symmetry close to hexagonal. For m = 0, 2, 3, 4 ,they consist of tetramers as basic units. The tetramers contain a pair of two molecules arranged side by side and another pair in the next stratum of the column, turned upside-down and rotated around the column axis at different angles for different m. In contrast, for m = 1, there is only one molecule in each stratum, with a four-strata 2(1) helical repeat. All molecules face up in one column, and down in the second column, of the monoclinic cell. This allows close and extended π-stacking, unlike in the disruptive up-down alteration from the case of m = 0, 2, 3, 4. Most of the 3D structures were observed only by cooling at rates of 1 °C/min or less. This complex helical self-assembly is representative for other classes of dendronized PBIs investigated for organic electronics and solar cells.     

Scattering of Two Spinless Particles in 3D Formulation with Coulomb Admixtures

Scattering of two spinless charge particles for simple forces including coulomb admixtures is calculated without partial wave decomposition. The coulomb interaction being taken is of the type of screened coulomb potential. For the forces range is not infinite, the standard scattering theory is applied. The differential and total cross section are calculated and coulomb effects are shown.     

Scattering of a Spin-{\frac{1}{2}} Particle Off a Spin-0 Target in a Simple Three-Dimensional Basis

Scattering of a spin- ${\frac{1}{2}}$ particle off a spin-0 target is formulated based on a simple three-dimensional momentum-spin basis. The azimuthal behaviour of both the potential and the T-matrix elements leads to a set of integral equations for the T-matrix elements in two variables only, namely the momentum’s magnitude and the scattering angle. Some symmetry relations for the potential and the T-matrix elements reduce the number of the integral equations to be solved by a factor of one half. A complete list of the spin observables in terms of the two-dimensional T-matrix elements is presented.     

Characterization of coupling efficiency of silicon microring resonator using add-drop filter model

This paper presents a way of accurate characterization of the coupling efficiency of silicon microring resonator through curve fitting approach using an add-drop filter model which considers not only the waveguide propagation loss but also the backscattering effect due to sidewall roughness. The effective coupling efficiencies for different coupling angles from five differently positioned chips of two wafers are measured by comparing the experimental curve with the theoretical fit obtained from the developed model. The comparison of the results from this model with the Finite-Difference Time-Domain (FDTD) simulation results shows that the discrepancies increase with larger coupling angle i.e. larger coupling length, since longer couplers are more sensitive to the fabrication inaccuracies. The results found in this paper can serve as a good design tool in future to streamline the design of microring based structures on the same technological process.     

Efficient synthesis of tertiary amine by direct N-alkylation of secondary amine with carboxylic acid using Ni (0) encat catalyst

In this article, direct N-alkylation of secondary amines with carboxylic acid is described. Readily available diversified carboxylic acid has been explored on variant secondary amines using encapsulated Nickel as catalyst and inexpensive sodium borohydride as the hydride source. High yields, mild reaction conditions, tolerance to sensitive functional group and facile operational procedure are the significance of the present methodology.     

Promising framework of nanocomposite materials: synthesis and radio-lanthanides labeling for nuclear medicine application

Journal of Radioanalytical and Nuclear Chemistry - Incorporation of fulvic acid (FA) into the framework of hydroxyapatite particle to synthesis NHAP functionalized with FA (NHAP-FA) as a new smart...     

Correction to: Sorption of radioactive cobalt onto nano calcium silicate/CuO composite modified by humic acid

Journal of Radioanalytical and Nuclear Chemistry - In the original publication of the article, Figs. 8, 9 and 10 were published incorrectly as linear regression.