Abstract

      The target derivative are gentamicin linked with L-Val- L-Ala by an ester linkage. These were synthesized by esterification method, which included the reaction of -OH hydroxyl group on (carbon No.5) of gentamicin with the acid chloride of the corresponding dipeptide, The preparation of new derivative of gentamicin involved protected the primary & secondary amine groups of Gentamicin, by Ethylchloroformate (ECF) to give N-carbomethoxy Gentamicin which was used for further chemical synthesis involving the free hydroxyl groups.

Then prepared dipeptide (L-Val- L-Ala) by conventional solution method in present DCC & HoBt then reacted with thionyl

The aim of this paper is the study of the influence of magnetic field on unsteady
flow of the second-grade fluid with constant viscosity. The equations which
controlled this type of fluid flow are complicated, so finding an analytical solution is
not easy, because it is a system of partial differential equations.We obtained an
expression for the velocity by using homotopy analysis method HAM.
It is found that the equations motion are controlled by many dimensionless
parameter, namely magnetic field parameter M and material constant α,
dimensionless film thickness β and unsteadiness parameter S.We have been studied
the influence of all the physical parameters, that mentioned above on the velocity
field, also a

Polycyclicacetal was prepared from the reaction of PEG with aldehyde derived from Erythro-ascorbic acid (pentulosono-ɣ-lactone-2,3-enedianisoate).All these compounds were characterized by Thin Layer Chromatography (TLC) and FTIR spectra and aldehyde was also characterized by (U.V-Vis), 1HNMR, 13CNMR, and mass spectra.The inhibitory effect of prepared polymer on the activity of human serum AcetylCholinesterase has been studied in vitro. The polymer showed a remarkable activity at low concentration (4.7x10-3 – 4.7x10-8M).

in this paper sufficient conditions of oscillation of all of nonlinear second order neutral differential eqiation and sifficient conditions for nonoscillatory soloitions to onverage to zero are obtained

In this research we study the effect of UV radiation on pure PC samples and doped samples with plasticizer (DOP) for different exposure times (6, 12, 18, 24h). The study have been made on the change in the IR spectra causes by the UV radiation on both kinds of samples, besides the morphology changes were also studied by the optical microscope. From the results we conclude that the increasing of exposure causes the elaboration of CO₂ and C₂ gases.

Nicotine was separated from eggplant and green pepper seeds (Solanaceous) by High Performance Liquid Chromatography (HPLC).The concentration of nicotine in the eggplant extract (0.871-0.877 μg/ml) was determined by injecting standard material with 0.5 and 1.5 μg/ml, while the concentrations of nicotine in green pepper extract (0.613-0.618 μg/ml) was determined when the standard material was injected with 0.5 and 1.5 μg/ml. The qualitative chemical data was calculated from derivations of the standard material. Nicotine concentration was measured qualitatively in both extracts through the calibration curve and method of the standard addition. This technique has high accuracy and compatibility, bringing the proportion of relati

      This study included the isolation and identification of Citrobacter freundii from 220 samples collected from inpatients and outpatients suffering from urinary tract infection (UTI) and identified at the laboratory of the General Samarra Hospital in Samarra City, Iraq. The study was conducted to investigate some of the virulence factors produced by C. freundii. The results showed that 67 isolates were  belonging to the C. freundii, with a rate of  30.45%. Twenty eight samples were from inpatients (41.8%)  and 39 samples were from outpatients. The bacterial identification was based on cultural and biochemical tests and confirmed by using VIT

Chlorine disinfection is a globally used method to ensure the safety of drinking water. However, it has not always been successful against viruses and, therefore, it is important to find new methods to disinfect water. Seventeen different coliphages were isolated from the treated municipal wastewater. These coliphages and MS2 were treated with different dosages of chlorine in drinking water, and a combined chlorine/ultraviolet irradiation treatment for the chlorine-resistant coliphages. Chlorine disinfection with 0.3–0.5 mg/L total chlorine (free Cl-dosage 0.12–0.21 mg/L) for 10 min achieved 2.5–5.7 Log10-reductions for 11 sensitive coliphages. The six most resistant coliphages showed no reduction with these chlorine concentra

In this paper, the series solution for unsteady flow for an incompressible viscous electrically conducting fluid of second grad over a stretching sheet subject to a transverse magnetic field is presented by using homotopy analysis method (HAM). Also we examines the effects of viscoelastic parameter, magnetic parameter and time which they control the equation of motion.