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ABSTRACT A simple and sensitive spectrophotometric  method for  the determination of paracetamol was explored, using zirconium(IV)  and vanadium(V)  oxides. The method was based on the oxidation of paracetamol by zirconium(IV) and vanadium(V)   m     alkaline  and  acidic  media  respectively.  The   stoichiometric studies indicated  a mole-ratio of  1: 1   for  the reactions of paracetamol  with both zirconium(IV)  and vanadium(V).  Effects  of other variables like  pH,  temperature and  time   were  determined  and  showed ...

ABSTRACT This work studied the effect of the binary and ternary combinations of pine needle (Pinus pinaster ) dust and bambara nut (Vigna subterranea) chaff with coal dust for briquette production. Briquettes of 100% of the pure coal and the biomass were produced first. The ratios for the blending were as follows 1:1 for the binary combination of each biomass with coal and with themselves, and 1:1:1 for the ternary ...

ABSTRACT The synthesis of N-heteroaryl substituted benzene sulphonamides and evaluation of their biological activities are reported. Synthesis was achieved by the reaction of benzene sulphonyl chloride  and  substituted  amino  heterocycle  in  dry pyridine.  The  structures  of  synthesized compounds were assigned by spectroscopic methods. The eight (8) synthesized compounds were evaluated for antibacterial and antifungal activities. The results showed that some of the new compounds exhibited activities comparable to ciprofloxacin and ...

ABSTRACT Zinc Oxide (ZnO) nanowires with hexagonal structure were successfully synthesized by chemical bath deposition technique. The obtained nanowires were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), energy dispersive X-ray analysis (EDX) and spectrophotometer. The SEM micrographs revealed the morphology of ZnO nanowires with diameter between 170.3 and 481nm and showed that the pH of the bath solution, 8.1 is the optimized value to form ZnO nanowires with ...

ABSTRACT The Schiff base ligand, 2-phenyl}imino)methyl]phenol was synthesized by condensing 1,3-diaminobenzene and 2-hydroxybenzaldehyde in absolute ethanol.  Its  Cr(III)  and   Cr(VI)  complexes  were  equally  synthesized.  The  ligand   was characterized via UV, IR and NMR spectroscopy, whereas the complexes were characterized based on UV and IR spectroscopy and conductivity values. Stoichiometric studies indicated 1:1 metal to ligand ratio for both complexes. Cr(III) complex absorbed at 1042.56 cm-1  υ(C-O), 532.37 cm-1 υ(Cr-N) and ...

ABSTRACT The  synthesis  of  new  angular  aza  phenothiazinones,  angular  azaphenoxazines  and  their derivatives are reported. Two key functional intermediates namely 2,6-diamino-4-chloro- pyrimidin-5-thiol and 7-chloro-5,8-quinolinequinone were successfully synthesized from readily available starting materials using such traditional organic methods as nitrosation, nitration, halogenation, reduction, oxidation, direct thiocynation and base-catalyzed hydrolysis. The new angular azaphenothiazinones and angular azaphenoxazinone were prepared by coupling the requisite intermediates. Condensation reaction between 2,6-diamino-4-chloro-pyrimidin-5-thiol or 2-aminothiophenol or 2-aminophenol ...

ABSTRACT Let H  be a real Hilbert  space and  K  a nonempty,  closed and  convex subset  of H.  Let T : K  →  K  be an asymptotically  nonexpansive  map with a nonempty  fixed points  set. n=1   Let {αn}∞ and  {tn}∞ be real sequences in (0,1).  Let {xn} be a sequence generated from an arbitrary x0  ∈ K by n=1         yn = PK ,       n ≥ 0 n=1 ...

ABSTRACT The  synthesis  of  five  mono-  and  five  bis-alkynylated  derivatives  of  quinoline-5,8-diones  is reported.  The  intermediate  6,7-dibromoquinoline-5,8-dione  was  obtained  by  nitrosation  of 8- hydroxyquinoline, followed by reduction and subsequent bromination and oxidation. The coupling reaction  of  6, 7-dibromoquinoline-5 ,8-dione  via  palladium-catalyzed  Sonogashira cross-coupling gave the alkynylated   products.  The chemical structures of the products were confirmed using spectroscopic  methods which include UV-visible spectrophotometry,  Fourier Transform-Infrared (FT-IR)  spectroscopy,   'H   and  'C-NMR  spectroscopy.   ...

ABSTRACT The kinetics and mechanisms of the redox reactions of   µ-oxo-bridged iron(III) complex ion Na4.12H2O denoted as Fe2 O4+, with the thiols-2-mercaptobenzothiazole(MBSH), 2- mercaptophenol(PhSH), 2-mercaptoacetic acid (MSH), and l-cysteine (RSH) have been investigated in  aqueous perchloric   acid medium at =1×10-4  mol dm-,3,I=0.05mol dm-3(NaClO4) and at T =27.0±0.1oC. The reactions were monitored under pseudo-first order condition .The rate of reaction was first-order in reductant and oxidant for all the systems giving ...

ABSTRACT The composition and bleaching properties of Nteje clay in comparison with two commercially available  adsorbents  (activated  carbon  and  fuller’s  earth)     were  investigated  to  study  its competence for use as an alternative to high cost imported adsorbents. The modification of the raw clay sample was carried out by acid activation to enhance the surface area of the clay by exchange of octahedral cations e.g Al3+, Fe3+ and Mg2+   with H+ ...

ABSTRACT Physicochemical  and bacteriological  analyses  of borehole  water  samples were randomly collected from ten boreholes which supply drinking water to various  communities  of Aninri,  Awgu  and  Oji River  Local  Government Areas of Enugu, Nigeria.  The boreholes were sampled in both dry and rainy seasons.   The  following  physicochemical   parameters:   pH,   temperature, colour, electrical conductivity, turbidity, total dissolved solids, hardness, calcium, magnesium, sodium, potassium, alkalinity, acidity, lead, copper, cadmium and iron were ...

ABSTRACT The study investigated the levels of organochlorine pesticide residues in both cocoa beans and soils of cocoa plantations in selected farms in Ondo State. Soil samples and cocoa pods were collected  from four major farms in the State. The pesticide residues  were extracted, cleaned up and analysed using Gas Chromatography-Electron  Capture Detector (GC-ECD). In the analysed cocoa samples, the ranges of the mean concentrations of the organochlorine pesticides were: ...

ABSTRACT Tandem amidation catalyzed synthesis of linear diazaphenoxazine carboxamide derivatives is reported. This was achieved by the reaction of 2-amino-3-hydroxypyridine and 2,3,5-trichloropyridine in aqueous basic medium which gave 3-chloro-1,9-diazaphenoxazine as white solid crystals. 3-Chloro-1,9-diazaphenoxazine was then subjected to Buchwald-Hartwig amidation coupling reaction with various amides namely formamide, phthalamide, 4- nitrobenzamide, benzamide and acetamide via water promoted catalyst preactivation protocol to afford the following, 3-amido derivatives of 1,9-diazaphenoxazine namely 3-formamido-1,9-diazaphenoxazine, 3- ...

ABSTRACT Physicochemical and bacteriological analyses of underground water resources in  Nkanu East and  Nkanu West  Local Government Areas of  Enugu state, Nigeria were carried out to evaluate the potability and quality of the rural water supplies   and   to   provide   baseline   data   for   future   quality   assessment. Underground water samples were collected from ten different boreholes in Nkanu East and Nkanu West LGAs. The parameters measured include temperature,  colour,  pH,  electrical  conductivity,  ...

ABSTRACT Palladium-catalysed  Suziki-Miyaura cross-coupling  (SMC) reactions of 6-chloro-5H benzophenothiazin-5-one,        11-amino-6-chloro-9-thio-5H-naphthopyrimido oxazin-5-one and  6-chloro-5H-naphthopyridooxazin-5-one with phenylboronic acid and 3-nitophenylboronic  acid were thoroughly  investigated.  The above intermediates were prepared by the reactions of 2-aminothiophenol,  4,5-diamino-6-hydroxylpyrimidine-2-thiol and 2- aminpyridin-3-ol  respectively  with 2,3-dichloronaphthalene-1,4-dione   in  a basic  medium using benzene/DMF as the solvent. Thereafter, each was subjected to the SMC reactions with phenylboronic acid and 3-nitrophenyl boronic acid, refluxing for 7-8 h at 110 C ...

ABSTRACT The  improvement  of  the  combustion  properties  of  coal  and  biomass  by  blending  and carbonization was investigated. Proximate and ultimate analysis of coal, sawdust,  corn cob and their blends were carried out using ASTM methods. The proximate and ultimate analyses were repeated on the five blends after carbonization at 500oC for one hour. Ten mixtures of coal-sawdust  and coal-corn cob blends were made into briquettes using starch binder. The calorific ...

ABSTRACT Palladium     catalysed     synthesis     of    substituted     2--3- methylbutanamide  (176) is reported. The  intermediate 2--3- methybutanamide     (175)     was     obtained     by     the     reaction     between     2--3-methybutanoic acid chloride (175) and ammonia. Substituted 2- -3-methylbutanamides (176a-f) were obtained by coupling 2--3-methylbutanamide (175) with various readily available substituted aryl halides via a Buchwald-Hartwig-type  cross coupling protocol. Structures of the synthesized compounds were confirmed using Fourier transform infrared (FT-IR), as well as  proton  and  carbon-13  Nuclear ...

ABSTRACT The concentrations of Ni, Mn, Cd, Cu, Zn, Pb and Cr, were determined in some pastas consumed in Nigeria, with a view to providing information on the dietary intakes of heavy metals and exposure of humans to toxic metals. The concentrations of these seven (7) elements were determined by atomic spectrometry after nitric acid/perchloric acid digestion. The concentrations of the metals (µg/g) in the locally manufactured pasta samples were ...

ABSTRACT Modification of coconut (Cocos nucicera L.) shell activated carbon with an Azo ligand: 1, 2– dihydro-1,5-dimethyl-2-phenyl-4-(E)–(2,3,4-trihydrophenyl)-3H-pyrazol-3-one (DDPTP) and its potentials for the removal of Cd2+, Pb2+ and Ni2+ from polluted water samples were studied. It was activated chemically using CaCO3 as the activating agent. Proximate analysis on the coconut shell showed 8.7 % moisture content, 10.4 % volatile matter, 3.2 % ash content and 77.7 % fixed carbon. The ...

ABSTRACT The removal of Pb(II) ions from aqueous model solution using zeolite has been investigated under different operational parameters like heavy metal ion concentration,  adsorbent  amount   and   particle  size.   The   zeolite   used   was synthesized and characterized using SEM and XRD analysis. The equilibrium adsorption capacity of  zeolite  used  for  lead  removal were  measured  and  the experimental  data  analyzed  by  means  of  Freundlich  and  Langmuir  isotherm models.  The  adsorption efficiency  of ...