SYNTHESIS AND CHARACTERIZATION OF MIXED LIGAND Mn(II), Co(II), Ni(II) and Cu(II) COMPLEXES OF SOME HYDRAZONES AND NITROGEN DONOR LIGANDS

  Mn(II), Co(II), Ni(II) and Cu(II) mixed ligand complexes of some Benzoyl hydrazones (hydrazide Schiff bases) with 1,10-Phenanthroline (Phen), 2,2′-bipyridine and ethylenediamine(en) were synthesized and characterized using metal analysis, molar conductivity, magnetic susceptibility, electronic spectra, infrared measurement and antimicrobial activity. The percentage metals of the complexes are in close agreement with their corresponding theoretical values. The molar conductance of some of the complexes that were soluble in nitromethane reveals that only [Co(H1L)2Bipy]Cl2 is a 1:2 electrolyte while [Cu(Phen)(H1)](NO3)H2O, [Cu(Bipy)H1L]NO3, [Cu(Phen)H1L]NO3, [Cu(H1L)(H1A)(NO3)H2O]NO3, and [Cu(H1HY)(H1A)(NO3)H2O].NO3.2H2O are 1:1 electrolyte. The electronic spectra displayed bands which were assigned to π→π*, n→π*, Charge transfer and d-d transitions. From the d-d transitions in the visible region of the spectra, it was suggested that these complexes have four-, five- and six- coordinate stereochemistries. The proposed geometries were backed up by the observed magnetic moments which were in line with the expected or theoretical values.  The infrared spectra gave bands that were assigned to ѵ(NH), azomethine ѵ(C=N) and ѵ(C=O) vibrational frequencies. The shift in the ѵ(C=O), ѵ(N-N), ѵ(NH), ѵ(C-N) and ѵ(C=N) bands in the spectra of the complexes reveals that there is coordination of the ligands to the metal centre. The complexes compared favourably well with Gentamicin and Ketoconazole with respect to antibacterial and antifungal activities respectively

MIXED LIGAND NICKEL(II) COMPLEXES OF BENZOYLTRIFLUOROACETONE WITH 2,2-BIPYRIDINE, 1,10-PHENANTHROLINE AND TETRAMETHYLETHYLENEDIAMINE: SYNTHESIS, SPECTROSCOPIC AND ANTIMICROBIAL PROPERTIES

A series of nickel (II) complexes of 4,4,4-trifluoro-1-phenyl-1,3-butanedione(bta) ligand mixed with 2,2¢-bipyridine (bipy), 1,10-phenanthroline (phen), and tetramethylethylenediamine(tmen) were synthesized and characterized by elemental analysis, IR and UV-Vis spectroscopy, magnetic  and antimicrobial studies . A distorted square pyramidal nickel(II) complexes with the formular [Ni(bta)(N-N)(X)].H2O was formed with the bta ligand, where bta coordinated with the nickel ion through the two oxygen atom, the N-N donor ligand bonding with two nitrogen atom and  the fifth coordination position occupied by the NO3 molecule. On the other hand, the complexes; [Ni(bta)2tmen] and [Ni(bta)(bzac)bipy].H2O exhibited an octahedral geometry. The microbiostatic activity revealed that the [Ni(bta)(phen)(NO3)].H2O and [Ni(bta)(bipy)(NO3)].H2O lacked antibacterial activity

Microbiology of Composting Pig Waste: Comparison of Vermicomposting and Open Heap Techniques

Against the background of an effective waste management, microbiological studies of composting pig waste were investigated. Freshly deposited excreta from confined pigs in a private pig farm in Benin City, Edo State, Nigeria were composted by two aerobic methods – vermicomposting and open heap. Microbial (bacterial and fungal) counts and characterization were carried out periodically within the 40 weeks of composting, using standard techniques. The results showed that only duration of composting significantly (p<.0.05) affected microbial counts as the counts decreased from the initial value at week zero to much lower value at week 40. A total of 274 bacterial and fungal isolates were recovered from the composting waste and majority (60.58%) were isolated from the open heap. Bacillus subtilis, Pseudomonas aeruginosa and Aspergillus flavus were the predominant isolates recovered (9.49% each), and were the only isolates recovered throughout the period of composting irrespective of the composting technique. Staphylococcus aureus and Salmonella typhimurium were the least isolated (1.09% each). Vermicomposting technique was recommended on health and environmental grounds

PHYSICOCHEMICAL STUDIES OF MANGANESE (II) AND COPPER (II) COMPLEXES AND THEIR ADDUCT

&nbsp;Bis(salicylaldehydato) manganese (II) and Bis(4,4,4-trifluoro-1-(2-Naphthyl)-1,3-butanedionato) copper(II),&nbsp; their 2,2'-bipyridine, ethylenediamine, 1,10-phenanthroline and tetramethylethylenediamine adducts have been synthesized and characterized by metal analysis, FT-IR, UV–Visible, magnetic susceptibility and antimicrobial activity. The complexes and adducts were obtained as brown, yellow or light green colour. The metal analyses were in close agreement with the theoretical values expected. The infrared spectra of the manganese(II) complex revealed the coordination of salicylaldehyde through the carbonyl group and the hydroxyl group, while 2,2'-bipyridine, ethylenediamine, 1,10-phenanthroline and tetramethylethylenediamine coordinated to the metal through the nitrogen atoms. The magnetic moment data suggests low-spin octahedral geometry for [Mn(sal)2(H2O)2] (μeff = 2.14 B.M), high-spin octahedral geometries for [Mn(sal)2(en)].5H2O (μeff = 5.50 B.M), [Mn(sal)2(phen)] (μeff = 6.2 B.M),[Mn(sal)2bipy](μeff =5.95 B.M)&nbsp; and [Mn(sal)2(tmen)](μeff =5.98 B.M.). The electronic measurements are indicative of a probable four-coordinate square planar geometry for [Cu(tfnb)2] while five-coordinate square pyramidal geometry are proposed for the copper(II) adducts. The complexes and adducts were screened against various bacteria and fungi. The copper complex and adducts were moderately active against fungal strain except [Cu(tfnb)2] and [Cu(tfnb)2en] in Aspergillus niger which showed pronounced activity and resistance respectivel

SYNTHESIS, CHARACTERISATION AND ANTIMICROBIAL ACTIVITIES OF MIXED LIGAND NICKEL(II),COPPER(II) AND ZINC(II) COMPLEXES OF BENZALDEHYDE WITH 1,10-PHENANTHROLINE, 2,2′-BIPYRIDINE AND ETHYLENEDIAMINE

Nickel(II), copper(II) and zinc(II) mixed ligand complexes of benzaldehyde with 1,10-phenanthroline, 2,2′-bipyridine&nbsp; and ethylenediamine have been synthesised and characterised by metal analysis, infrared spectroscopy, electronic spectra studies, magnetic susceptibility measurement and antimicrobial activities. The infrared spectra of the complexes confirmed the coordination through the carbonyl oxygen of the benzaldehyde while the electronic transitions are consistent with the adoption of octahedral geometry for all the synthesised complexes. The magnetic moment of the synthesised complexes suggested that all the complexes were paramagnetic except Zn(II) complex which was diamagnetic. The microbial susceptibility testing showed that the copper complexes had stronger antibacterial and antifungal activity than nickel and zinc complexes. Notably, [Cu(Bz)2Bipy(NO3)2] and [Ni(Bz)2(phen)Cl2].H2O showed no antifungal activity

SYNTHESIS, CHARACTERISATION AND ANTIMICROBIAL ACTIVITY OF MIXED-LIGAND NICKEL(II) AND COPPER(II) COMPLEXES OF SALICYLALDEHYDE WITH 2,2′-BIPYRIDINE, 1,10-PHENANTHROLINE AND ETHYLENEDIAMINE

Nickel(II) and copper(II) mixed-ligand complexes of Salicylaldehyde with 2,2′-bipyridine, 1,10-phenanthroline and ethylenediamine were synthesised and characterised by molar conductance, spectroscopic measurement, room temperature magnetic measurement and antimicrobial activity. The complexes showed different shades of colour and were non-electrolyte. The infrared spectra of the complexes confirmed the coordination through the lone pair of the carbonyl oxygen of the Salicylaldehyde. The electronic transitions were consistent with the adoption of five-coordinate geometry for the copper complexes and six-coordinate geometry for the nickel complexes. The microbial susceptibility testing showed that the copper complexes had stronger antifungal activity than the antibacterial activity. The antifungal activity was more pronounced at 12.5 – 100 mg/mL, while the antibacterial activity was generally restricted to 100 mg/mL. Notably, [Cu(Sal)2(bipy)] showed no antifungal activity while [Cu(Sal)2(en)] showed neither antifungal nor antibacterial activity. Among the nickel complexes only [Ni(Sal)2(phen)] had both antifungal (except Fusarium) and antibacterial activity. [Ni(Sal)2(en)] was neither antifungal nor antibacterial

Prevalence of intestinal parasitic infections among HIV patients in Benin City, Nigeria

This study was carried out to determine the presence of intestinal parasites and their correlation with CD4+ T-cell counts and demographics among human immunodeficiency virus (HIV)-positive patients in Benin City, Nigeria. Stool specimens from 2,000 HIV-positive patients and 500 controls (HIV-negative individuals) were examined for ova, cysts, or parasites, using standard procedures. In addition, patient's blood samples were analyzed for CD4 counts by flow cytometry. An overall prevalence rate of 15.3% was observed among HIV-positive patients while 6.2% was noted among non-HIV subjects. HIV status was a significant (P<0.0001) risk factor for acquiring intestinal parasitic infections. Male gender, CD4 count <200cell/µl, and diarrhea were significantly associated with an increased prevalence of intestinal parasitic infections among HIV-positive patients. The level of education, occupation, and source of water among HIV patients significantly (P<0.0001) affected the prevalence of intestinal parasitic infections. Ascaris lumbricoides was the most predominant parasite in both HIV-positive patients and controls. A CD4 count <200 cells/µl was significantly associated with only Isospora belli and Cryptosporidium infections. The presence of pathogenic intestinal parasites such as A. lumbricoides, hookworm, Giardia intestinalis, Entamoeba histolytica, Trichuris trichiura, and Taenia species among HIV-infected persons should not be neglected. Cryptosporidium species and I. belli were the opportunistic parasites observed in this study. Routine screening for intestinal parasites in HIV-positive patients is advocated

Interpretative and predictive modelling of Joint European Torus collisionality scans

Transport modelling of Joint European Torus (JET) dimensionless collisionality scaling experiments in various operational scenarios is presented. Interpretative simulations at a fixed radial position are combined with predictive JETTO simulations of temperatures and densities, using the TGLF transport model. The model includes electromagnetic effects and collisions as well as □(→┬E ) X □(→┬B ) shear in Miller geometry. Focus is on particle transport and the role of the neutral beam injection (NBI) particle source for the density peaking. The experimental 3-point collisionality scans include L-mode, and H-mode (D and H and higher beta D plasma) plasmas in a total of 12 discharges. Experimental results presented in (Tala et al 2017 44th EPS Conf.) indicate that for the H-mode scans, the NBI particle source plays an important role for the density peaking, whereas for the L-mode scan, the influence of the particle source is small. In general, both the interpretative and predictive transport simulations support the experimental conclusions on the role of the NBI particle source for the 12 JET discharges