12 membered Schiff base macrocyclic ligands, 6,7,14,15-tetra phenyl-1,2,3,4, 4a,8a, 9,10, 11,12, 12a,16a-dodecahydro dibenzo [b,h] [1,4,7,10] tetraazacyclododecine L1, and 14 membered Schiff base macrocyclic ligands, 6,8,15,17-tetramethyl-1,2,3,4, 4a,7,9a, 10,11,12,13,13a,16,18a-tetra decahydro dibenzo[b,i] [1, 4,8,11] cyclotetradecine tetraaza L2, 7,16-bis(2,4- dichloro benz ylidene)-6,8,15,17-tetra methyl-1,2,3,4, 4a,7,9a, 10, 11,12, 13, 13a,16,18a-tetra deca hydro dibenzo [b,i] [1,4,8,11] tetra azacyclo tetra decine L3 and 6,8,15, 17-tetramethyl-1,2,3, 4,4a,9a,10, 11,12,13,13a,18a-dodecahydro dibenzo [b,i] [1,4,8, 11] tetraazacyclo tetradecine (7,16-diylidene) bis(methanylyli dene) bis (N,N-dimethylaniline) L4 were synthesized by condensation reaction between diketone and aliphatic diamines. The metal complexes of the types, [ML1Cl2], [ML2Cl2], [ML3Cl2] and [ML4Cl2] [M= Co(II), Ni(II), Cu(II), Mn(II), Hg(II), and Fe(II)] were prepared by interaction of ligands, L1, L2, L3 and L4 with metal(II) ions. The ligands and their complexes were characterized by elemental analysis, magnetic susceptibility, conductivity measurements and IR, 1H and 13C NMR, UV–Vis spectral studies. The thermal stability of the complexes was also studied by TGA analyses. These studies show that all the complexes have octahedral arrangement around the metal ions. We used CB-Dock, a novel blind docking technique that aims to improve docking precision. With the aid of the cutting-edge docking program Autodock Vina, software online, molecular docking studies were used to evaluate the biological significance of the synthesized ligands and identify the probable and efficient binding mechanisms between the various ligands and the active site of the receptor protein. Affinity binding of both Ligand L3 and L4 to Penicillin binding protein 2x (chain B) with PDB 1PYY were much better than to Penicillin binding protein 2B (chain A) with PDB 1WAE due to the presence of hydrogen and halogen bonds. Therefore, they can be more recommended for drug design study to inhibit bacterial growth due their bioavailability. The biological activities of all compounds were evaluated like in-vitro antioxidant activity or percentage free radical scavenging effect via DPPH method against standard ascorbic acid and in vitro anticancer activity via MTT assay against colon cancer cell lines. Results of the biological activities showed that complex CuL3Cl2 exhibited the highest anti-cancer activity against colon cancer cell line i.e. 70.72±6.3 μg/ml among other copper complexes whereas compound CuL3Cl2 showed best antioxidant activity against ascorbic acid i.e. 75.07±1.96 μg/ml. While the biological activities showed that complex CuL4Cl2 exhibited the highest anti-cancer activity against colon cancer cell line i.e. 42.05±7.4 μg/ml among other copper complexes whereas compound CuL4Cl2 showed best antioxidant activity against ascorbic acid i.e. 65.47±1.37 μg/ml.
This paper presents a method to organize memory chips when they are used to build memory systems that have word size wider than 8-bit. Most memory chips have 8-bit word size. When the memory system has to be built from several memory chips of various sizes, this method gives all possible organizations of these chips in the memory system. This paper also suggests a precise definition of the term “memory bank” that is usually used in memory systems. Finally, an illustrative design problem was taken to illustrate the presented method practically.
(2)
(3)
Background: Bacteriocin is a peptidic toxin has many advantages to bacteria in their ecological niche and has strong antibacterial activity. Objective: The aim of this study was to evaluation of bacteriocin using Streptococcus sanguinis isolated from human dental caries.
Subjects and Methods: Thirty five streptococcus isolates were diagnosed and tested for their production of bacteriocin, and then the optimal conditions for production of bacteriocin were determined. After that, the purification of bacteriocin was made partially by ammonium sulfate at 95% saturation levels, followed by and gel filtration chromatography
... Show More
Minister Yacoub Ben Keles distinguished himself with leadership and administrative talents, as well as his abilities in the field of jurisprudence, which made him the top political, administrative and cultural scene of the Fatimid state and left its mark on it by influencing its fateful decisions.
He was the son of Kels of the Jews of Baghdad, where he learned writing and arithmetic, and moved with his father to Syria and then carried him to Egypt.
Egypt embraced the son of Kels, living in a transitional period from the Achaishid era to the Fatimid period. Both these two covenants reconciled this man to his career until he became minister in the Fatimids in 368 A.H. / 978 A.D.
His character was overshadowed by most of the state'
(2)
(11)
(10)
This paper reports an experimental study regarding the influence of vertical oscillations on the natural convection heat transfer from a vertical channel. An experimental set-up was constructed and calibrated; the vertical channel was tested in atmosphere at 25o
C. The channel-to-ambient temperature difference was varied with the power supply to the electrical heater ranging between
15W to 70W divided into five levels. Data sets were measured under different operating condition from a test rig under six vibrating velocities (VVs) levels ranging from (5-30 m/s) in addition to the stationary state. The results show that the maximum heat transfer enhancement factor (E) occurs at Rayleigh number (Ra=2.328×103 ) and vibrational Reynol
Biodiesel is an environmentally friendly fuel and a good substitution for the fossil fuel. However, the purity of this fuel is a major concern that challenges researchers. In this study, a calcium oxide based catalyst has been prepared from local waste eggshells by the calcination method and tested in production biodiesel. The eggshells were powdered and calcined at different temperatures (700, 750, 800, 850 and 900 °C) and periods of time (1, 2, 3, 4 and 5 hr.). The effect of calcination temperature and calcination time on the structure and activity of the solid catalyst were examined by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Brunaure-Emmett-Teller (BET). The optimum catalyst performance was obtained at 900 °C
... Show More
(11)