Rafidain Journal of Science

Four pathogenic bacteria isolated from the sewage in this study : Pseudomonas aeruginosa , Escherichia coli , Staphylococcus aureus and Proteus mirabilis. Escherichia coli in addition to Pseudomonas aeruginosa were sensitive to the Pseudomonas aeruginosa bacteriophages that isolated from the sewage .Three other Pseudomonas specieces were tested for the sencitivity to the isolated bacteriophages only Pseudomonas specieces with green and yellow pigmentation on Nutrient agar were sensitive to the isolated phages.

The interaction between ascorbic acid (AA) and sodium nitroprusside (Niprus or Nipride) (SNP) was studied at pH 7.3 phosphate buffer 0.06 M solution using spectrophotometric method. The stability constants (K) were determined at different temperatures (280, 289, 295, 298, 303, and 310 ْK). Van't Hoof"s plot was obtained and thermodynamic parameters (free energy change ΔG, enthalpy change ΔH, and entropy change ΔS) were determined. The stability constants were investigated in different surfactants (sodium dodecyl sulfate SDS, cetyltrimethylammonium bromide CTAB, and Triton X-100). The effect of pH (4-8) on stability constants were also studied.

A simple and sensitive procedure for spectrophotometric determination of yttrium (III) in aqueous solution has been developed. The method is based on the reaction of yttrium with pyrocatechol violet at pH 7.6 to form a blue–violet complex which has maximum absorption at 595nm. Beer's law is obeyed over the concentration range 1-100 µg/25ml, (i.e., 0.04-4.0ppm) of yttrium with a molar absorptivity of 8.365×103 l.mol-1.cm-1. The accuracy (relative error) is (+0.33― -0.31%) and relative standard deviation is better than ±1.63%. The method has been successfully applied to the determination of yttrium in river and sea water .

Metal complexes of general formula [M(L)2]Cl2 and [Fe(L)2Cl2] where M is Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) and L is the Schiff base, 2-(pyrimidin-2-yliminomethyl) furan (FAP) are prepared. The complexes were characterized by analytical as well as spectroscopic, magnetic and conductance measurements. The infrared spectra of the complexes agree with coordination to the central metal atom through the nitrogen of the azomethine group and oxygen of the furan ring. Magnetic susceptibility data coupled with electronic spectra suggest a distorted octahedral structure for the Fe(II) complex, a tetrahedral geometry for the Mn(II), Co(II) and Zn(II) complexes, and a square planar for the Ni(II) and Cu(II) complexes. Conductance measurements suggest the 1 :2 electrolytic nature of the complexes with the exception of the Fe(II) complex as of a non-electrolytic nature.

In the present work, the focal properties of electrostatic lens consist of three cylindrical electrodes were intensively investigated . Each electrode spaced of (0.1) diameter apart. Special case such as a zoom lens is considered and the results are obtained as a function of the final-to-initial voltage ratios. It is found that the three-element lens could be operated with the whole focus properties in a useful mode. The calculations are carried out by using the LENSYS software package.