Utilization of amino resin for emulsion paint formulation: Effect of urea formaldehyde viscosity on urea formaldehyde and soybean oil copolymer composite
January 2010
In our continuous desire to develop a paint binder from amino resin, the effect of urea formaldehyde (UF) viscosity on a copolymer composite derived from the copolymerization reaction between urea formaldehyde (UF) and soybean oil (SBO) to give urea formaldehyde/ soybean oil copolymer composite (UF/SBO) was investigated. Some physical properties of (UF/SBO) obtained at different viscosities (5.11 - 260.04 mPa.s) were...
Design and synthesis of nano heterogeneous supported catalysts for olefin polymerization
December 2009
The polymerization of olefins was studied using heterogeneous cobalt nickel (oxide) bimetallic catalyst. The prepared catalyst was subjected to calcination at different temperatures. This treatment results in the formation of different phases with multiple oxidation states. The characterization of the catalyst was carried out by XRD, SEM, EDX, TGA, FTIR and TPR/TPD. The catalytic activity was studied for the...
Corrosion inhibition of aluminum in 2.0 M hydrochloric acid solution by the acetone extract of red onion skin
December 2009
The inhibition efficiency of acetone extract of red onion skin on aluminium in hydrochloric acid solutions has been evaluated by weight loss techniques. Values of inhibition efficiency obtained are dependent upon the concentration of inhibitor and temperature. Generally, inhibition was found to increase with inhibitor concentration, half-life, activation energy but decrease with temperature and first-order rate constant...
Synthesis of some 2,5- diamino-3,6- dibromo -1,4-benzoquinones
December 2009
A group of 19 compounds of the type 2,5-diamino-3,6-dibromo-1,4-benzoquinones were prepared and spectroscopically elucidated through IR ,UV-VIS, NMR and MS. Coupling of the intermediate 2,3,5,6-tetra bromo-benzoquinone with the required aryl amines furnished the required compounds. The prepared compounds were found to possess antimicrobial activities when tested against four standard bacterial organisms and two standard...
Some chemical constituents of the leaves of Cassia nigricans Vahl
November 2009
The methanol extract of the leaves of Cassia nigricans Vahl. (family; Leguminosae) was investigated. Chromatographic techniques were used to purify the crude extract. The gas chromatography/mass spectrometric analysis of the extract revealed the presence of five compounds, identified as 4-hydroxyanthraquinone-2-carboxylic acid; heptadecanoic acid,14-methyl-,methyl ester; bis (2-ethylhexyl) phthalate;...
The inhibition of corrosion of zinc in 2.0 M hydrochloric acid solution with acetone extract of red onion skin
November 2009
The inhibition of the corrosion of zinc by acetone extract of red onion skin in hydrochloric acid solutions has been studied using weight loss method. The results of the study reveal that different concentrations of the extract inhibit zinc corrosion. Inhibition efficiency of the extract is found to vary with concentration and temperature. The active component in red onion skin is quercetin. Acetone extract of red onion...
Design, synthesis and bioassay of novel metal complexes of 3-amino-2-methylquinazolin-4(3H)-one
November 2009
New ligand 3-amino-2-methylquinazolin-4(3H)-one (L) has been synthesized in good yield by the reaction of anthranilic acid with acetic anhydride then replaced the oxygen with nitrogen of hydrazine. When the ligand react with Co(II), Ni(II) and Cu(II) a new complexes are formed. The chemical structure of all prepared compounds were characterized by FT-IR, elemental analysis, 1H-NNR and UV/visible spectra, moreover...
Phytochemical constituents of some selected medicinal plants
November 2009
Tannins, saponins, phlobatannins, flavonoids, anthraquinones, terpenoids, steroids, alkaloids, carbohydrates and glycosides distribution in four medicinal plants belonging to different families were investigated and compared. The medicinal plants investigated are Carica papaya, Ocimum gratissimum, Adenia cissampeloides and Cymbopogan citratus. All the plants were found to contain tannins,...
Characterization and determination of chlorogenic acids (CGA) in coffee beans by UV-Vis spectroscopy
November 2009
In this research characterization and method for determination of CGA in green and roasted coffee beans have been reported by UV-Vis spectroscopy. The optical transition properties and solvent effects of CGA were measured in different polar-solvents. After characterization of the electron transition of the standard solutions, a method was developed for UV-Vis spectrophotometer determination of CGA in coffee beans. The...
Behavior of esters in blend and its possible application
November 2009
By esterification of corresponding acids and alcohols, polyol ester of pentaeritritol–tetra–oleate (PETO) and diester of dioctyladipate (DOA), were synthesized. Each synthesis was confirmed through the comparison of some important physical and chemical properties of obtained adducts, with those of reported values. Following this step, three blends of PETO and DOA were prepared and their important physical...
Lixiviation of manganiferrous aluminosilicate mineral in hydrochloric acid
October 2009
A study of the lixiviation of Manganiferrous Aluminosilicate Mineral in hydrochloric acid has been undertaken. Experiments on quantitative lixiviation of the mineral showed that its dissolution rate depends on hydrogen ion concentration, reaction temperature and particle size. The activation energy calculated from the experimental data was 34.19 kJ/mole and this suggests a diffusion controlled mechanism. A reaction...
Evaluating the efficiency of a textile wastewater treatment plant located in Oshodi, Lagos
October 2009
The major part of textile processes is based on chemical reactions carried out in aqueous heterogeneous systems which eventually generates effluents of extremely variable composition and constitute an environmental risk of major concern. This study, focused on investigating the characteristic of effluent from textile industry which generates about 1577 m3 wastes per day and the effectiveness of the wastewater...
Antioxidant and anticancer activities of doum fruit extract (Hyphaene thebaica)
October 2009
The antioxidant capacity of doum fruit extract and the total phenolic content were analyzed. The antioxidant capacity was estimated by DPPH and iron chelating assays. Quercetin, ascorbic, BHT and tannic were used as positive controls. Also the effect of doum extract on viability of acute myeloid leukemia was studied. The results showed that the total phenolic content were 0.5 µg/ 3 µg dried extract sample as...
Nano-Titanium dioxide (TiO2) mediated simple and efficient modification to Biginelli reaction
October 2009
We report an efficient titanium dioxide (TiO2) nanopowder catalyzed and microwave induced, much improved modification to original Biginelli reaction reported in 1893 involving fast reaction kinetics. Key words: Titanium dioxide, biginelli reaction, microwave, fast kinetics.
Determination of anions by ion chromatochraphy in water samples of Baghdad city
September 2009
Determinations of common anions by IC methods in Baghdad were carried out in this investigation. The optimum values of the instrumental parameters were reached best in relative standard deviation (RSD), correlation coefficient (r2) and method detection limits (MDLs) and other parameters to proving the precision and accuracy of this method. Both peak height (PH) and peak area (PA) were used for the evaluation of the IC...
Vitamin B12 models: Synthesis and characterization of cyano bridged dicobaloximes and antimicrobial activity
September 2009
Reactions of the cyanide complexes of the type Co(CN)(DH)2L moiety (where L= thiourea, acetamide, formamide, semicarbazide, pyrazole and aniline; DH = dimethylglyoxime) with the corresponding benzyl(aqua)cobaloxime PhCH2Co(DH)2OH2 gives a series of homometallic cyano-bridged compounds of the type PhCH2Co(DH)2CNCo(DH)2L. All these complexes have been synthesized and characterized by means of IR,...
Organometallic gold (III) bis-pentafluorophenyl-arylazo imidazole: Synthesis and multinuclear NMR investigation
September 2009
Reaction of [Au(C6F5)2(OSO2CF3)2] with RaaiR´ in dichloromethane medium followed ligand addition leads to [Au(C6F5)2(RaaiR/)](OTf) [RaaiR/ = p-R-C6H4-N=N-C3H2-NN-1-R/, (1 - 3), abbreviated as N,N/-chelator, where N(imidazole) and N(azo) represent N and N/, respectively; R = H (a), Me (b), Cl (c) and R/ = Me (1), CH2CH3 (2), CH2Ph (3), OSO2CF3 is the triflate anion,...
Comprehensive scientific demystification of Kigelia africana: A review
September 2009
Medicinal plant plays a vital role in the management of various diseases. Kigelia africana popularly known as the Sausage tree, Kigelia pinnata is a multipurpose medicinal plant with many attributes and considerable potentials. The plant has traditional uses which include anticancer, antiulcer, anti-aging, antioxidant, and anti malarial. It is also widely applied in the treatment of genital...
Effect of heating on the chemical stability of two brands of metronidazole suspension
August 2009
Metronidazole suspension is available in most developed countries as a prescription only medicine and in the form of an extemporaneous preparation of 90 days shelf-life. In Nigeria, it is available on the shelf with shelf lives of 2 - 4 years. It is available from at least 20 local manufacturers. This work has determined the shelf life of two brands of metronidazole suspension using accelerated stability testing method....
Kinetics and mechanism of elimination of ethyl acetate in the gas phase: A theoretical study
August 2009
Using the PM3 semi-empirical quantum mechanical molecular orbital method, a procedure was devised to study the gas phase pyrolytic reaction of ethyl acetate in order to gain a deeper insight into both its kinetics and mechanism. By considering the involvement of formal charges and geometrical changes in the activation, a mechanism was proposed in which a pre-equilibrium of acidic proton transfer is followed by the rate...
Modelling of the adsorption of zn2+ from aqueous solution by modified and unmodified tiger nut shell
August 2009
Adsorption of Zn (II) ions from aqueous solutions was studied in a batch system using Tiger nut shells. The optimum condition for the adsorption of Zn (II) ions from aqueous solution by these shells was investigated by considering the extent of adsorption with respect to contact time, initial metal ion concentration, particle size of the adsorbent and modification of the adsorbent with H2SO4. The extent...
Antidiarrhoeal effects of the root extracts of Guiera senegalensis in male mice
August 2009
The antimicrobial activities of aqueous and methanol extracts of Guiera senegalensis were studied against some enteropathogens by agar-well diffusion method. Both extracts inhibited the growth of Streptococcus Pneumonia, Escherichia coli, Staphylococcus aureus, Enterobacter cloacae, Salmonella sppand Pseudomonas euroginosa. The methanol extract was more effective on S. Pneumonia, E. coli, S....
The preparation of methyl benzoate and methyl salicylate on silica gel column
July 2009
An investigation of the acid catalyzed esterification of benzoic acid and salicylic acid with methanol on silica gel solid support system was carried out. The method involved distilling continuously or refluxing the alcohol over the packed column. The conventional method of esterification was also carried out to assess the advantages of the packed column method on improved yield and easier work-up procedure. This...
Molecular complex piperidine-CO2
July 2009
Piperidine absorbs CO2 in air to form the molecular complex: piperidinium-1-piperidinecarboxylate which was characterized by X-ray single crystal diffraction. The crystal structure was determined to be triclinic, space group P - 1 with a = 6.403(3) Å, b = 9.437(5) Å, c = 9.928(5) Å, ï¡ = 104.90(4)°, ï¢ = 102.35(4)°, g = 94.63(4)°, Z = 2. The complex is...
Physiochemical properties and micronutrients status of farmland soils in Abraka, Nigeria
July 2009
Micronutrients are as important as macronutrients in crop production. It is therefore imperative to have an idea of their availability in farmlands. To this end 20 soil samples were collected from 10 locations in Abraka (10 topsoil and 10 subsoil) to ascertain the level of total micronutrients. The total cationic micronutrients were determined using atomic absorption spectrophotometer (AAS). Fe has a range between 2214...
The proximate and mineral composition of three leafy vegetables commonly consumed in Lagos, Nigeria
June 2009
Analysis of proximate composition and mineral nutrients of three commonly consumed vegetables Amaranthus cruentus, Celusia argenta and Corchorus olitorius leaves was carried out using standard methods of food analysis. The mean leaves moisture content is 23.57, 15.58 and 30.90% respectively for A. cruentus, C. argenta and C. olitorius. The vegetables have high ash content ranging from 21.30...
Selective synthesis applying amino acids with basic side chains as peptide precursors
June 2009
Synthesis of protected amino acid derivatives has long been established as one of the most useful methods for peptide coupling, with applications in studies involving receptor-binding affinities and in protein stereochemical studies to elucidate enzymatic mechanisms. Amino acid esters incorporating glycine, proline, phenylalanine and related methyl esters have often been synthesized due to their usefulness,...
Seasonal variation of some physico-chemical properties of borehole water in Abraka, Nigeria
June 2009
The influence of seasonal changes on the properties of the borehole water in Abraka Ethiope east LGA Delta state, Nigeria was investigated. Composites samples from 7 representative quarters in Abraka township were collected and assessed for both dry and wet seasons. The vales of the various parameters were as follows: pH 6.3 to 7.1 for dry season and 6.2 to 8.00 for wet season; conductivity 62 to 84...
Characterization of clays in Odukpani, south eastern Nigeria
May 2009
A combination of analytical techniques such as atomic absorption spectroscopy (AAS), X-ray diffraction (XRD), infra red spectral (IR) analysis, energy dispersive analysis of X-ray (EDAX), differential thermal analysis (DTA) and thermogravimetric analysis (TGA) were employed to characterize clays from Odukpani, Cross River State, Nigeria. The samples were also subjected to physico-chemical tests. The results...
Polycyclic aromatic hydrocarbons (PAHs) contamination of synthetic industrial essential oils utilized in Northern Nigeria
May 2009
This paper provides supplementary information to earlier elucidations on the level of dioxin contaminations of synthetic industrial essential oils (SIEOs), commonly referred to as Turare (Hausa Language) utilized in Northern Nigeria. In this work, fifteen typical samples of this product was analysed for the EPA-16 targeted Polycyclic Aromatic Hydrocarbons (PAHs) using GC-MS methodology. The result revealed...
Spectrophotometric and conductometric studies of the thermodynamics complexation of Zn2+, Cu2 +, Co2 +, Ni+2 and Cd2+ ions with a new schiff base ligand in acetonitrile solution
May 2009
The complex-formation reactions between Cu2+, Zn2+, Co2+, Ni2+ and Cd2+ ions with 2-[(E)-(2-(2-(pyridine-2-yl)-ethylthio)ethylimino)methyl]-4-bromophenol(PYTABr) has been studied by spectrophotometric and conductometric methods in acetonitrile at various temperatures. Formation constants of the 1:1 and 1:2 (metal ion to ligand) complexes were evaluated from computer fitting of the absorbance-mole...
Studies on the effects of the honey of two floral types (Ziziphus spp. and Acelia spp.) on organism associated with burn wound infections
May 2009
The honey of 2 Nigerian honey of 2 floral types (Ziziphus spp. and Acacia spp.) was studied. Standard physicological composition of honey quality, that is, ash, pH, acidity, color, refractive index, conductivity, moisture, mineral content, hydroxymethyl furfural (HMF) contents and diastae number (DN) of the spp were determined. Compositional variation due to the floral types shows...
A comparative assessment of soil pollution by polycyclic aromatic hydrocarbons in two Niger Delta communities, Nigeria
March 2009
This study determined, in comparison with guideline limits, the levels of Polycyclic Aromatic Hydrocarbons (PAH) in the soils at Eleme (highly industrialized) and Ahoada East (less industrialized) communities in the Niger Delta Area. Sixteen grab soil samples with 8 samples each from different locations in each community were collected at depth 0 - 15 cm using an auger. About 500 g of soil from each...
Methylene blue (MB) adsorption from glycerol solution onto the twin habit of α-goethite
March 2009
Adsorption of methylene blue onto the surface of synthetic twin habit of α-goethite habit has been investigated in glycerol solution at 25, 30 and 35°C. For the twin habit adsorbent, it appears the results are consistent with an adsorbed phase confined to monolayer model with edgewise orientation of methylene blue (MB) molecules on the surface. Composite isotherms were calculated from the apparent...
Solid phase extraction of Cd(II) using mesoporous organosilicas and determination by FAAS
March 2009
A simple and reproducible method for the rapid extraction and determination of trace amounts of Cd(II) ions using mesoporous organo-silicas mesoporous silica and atomic absorption spectrometry is presented. Common coexisting ions did not interfere with the separation and determination. The preconcentration factor was 100 (1 ml elution volume) for a 100 ml sample volume. The limit of detection of...
Anthocyanins from leaf stalks of cassava (Manihot esculenta Crantz)
February 2009
The anthocyanins, cyanidin 3-O-(6’’-O-a-rhamnopyranosyl-b-glucopyranoside) (1) and delphinidin 3-O-(6’’-O-a-rhamnopyranosyl-b-glucopyranoside) (2) isolated from the leaf stalks of cassava (Manihot esculenta Crantz) by a combination of chromatographic techniques, and their structures were elucidated mainly by the use of homo- and heteronuclear magnetic resonance spectroscopy. The...
Phytochemical screening and toxicity studies of the aqueous extract of the pods pulp of Cassia sieberiana DC. (Cassia Kotchiyana Oliv.)
February 2009
The study was conducted to screen for the phytochemical constituents of Cassia sieberiana. The acute toxicity value and the effect of the aqueous extract of the pods of C. sieberiana on serum transaminases and alkaline phosphatase (ALP) were also measured in rats after five weeks of daily oral administration of grade doses (200 - 1600 mg/kgbody weight) of the extract. Phytochemical...
Isolation, characterization and antibacterial activity screening of ethoxyamine tetrahydroxyanthocyanidines from Detarium senegalense gmelin stem bark
January 2009
Detarium senegalense F. Gmelin (Leguminasae) is well-known Nigerian food and medicinal plant, commonly used in phytomedicine to cure diseases and heal injuries. The ethanol stem barks extract of D. senegalense affords an anthocyanidin alkaloid (2-methoxyamine 3,4,5,7 – tetrahydroxy anthocynadines). The structure was elucidated using NMR spectroscopy in combination with IR and MS spectral data....
Adsorption of the proteins of white wine onto activated carbon, alumina and titanium dioxide
January 2009
The study investigated the adsorption capacities of bovine serum albumin (BSA), ovalbumin (OVA) and mucin (MUC) onto titanium dioxide, alumina and activated carbon, for the purpose of investigating the optimum conditions of pH and cations concentration of white wine required for the haze removal process. The results showed that the amounts of adsorbed OVA and BSA onto the three adsorbents were 1.32 ±...
Simultaneous kinetic determination of paracetamol and caffeine by H-point standard addition method
January 2009
A very simple and selective spectrophotometric method for simultaneous kinetic determination of paracetamol and caffeine using H-point standard addition method (HPSAM) was described. The method was based on difference in the rate of oxidation of these compounds with Cu(II)-neocuproine system and formation of Cu(I)–neocuproine complex which monitored at 453 nm by spectrophotometer at pH 5.0 in the...
One-pot synthesis of some (1H)-quinoxalin-2-ones
January 2009
o-phenylenediamine and 4-benzoyl-1,2-diaminobenzene react with ethyl bromoacetate in basic medium under mild reaction conditions to give directly 1H-quinoxalin-2-one (2) and 7-benzoyl-1H-quinoxalin-2-one (4), respectively. Alkylation at the nitrogen atoms of 7-benzoyl-3,4-dihydro-1H-quinoxalin-2-one (3) and compound 4 has been also carried out. Key words: o-phenylenediamines,...
Investigation of heavy metals contamination of edible marine seafood
December 2008
Levels of trace metals (Co, Cu, Fe, Mn and Zn) were determined in some marine species (Tilapia zilli, Callinectes sapidus and Littorina litorea) collected during different seasons from Ondo coastal region, Nigeria. Both species-dependent variability, residency of the organism and temporal variations were pronounced. A general trend in concentration with the following in decreasing order occurred: Fe > Cu >>>...
Inhibition of the corrosion of mild steel in HCl by sparfloxacin
December 2008
Inhibitive and adsorption properties of sparfloxacin for the corrosion of mild steel in HCl have been studied using gravimetric, gasometric and thermometric methods of monitoring corrosion. Sparfloxacin is found to inhibit the corrosion of mild steel in HCl. At 303 K, inhibition efficiency obtained for sparfloxacin from gravimetric, gasometric and thermometric methods were found to range from 79.68 to 97.47%, 86.67 to...
Corrosion inhibitive properties and adsorption behaviour of ethanol extract of Piper guinensis as a green corrosion inhibitor for mild steel in H2SO4
November 2008
The corrosion inhibition of mild steel by ethanol extract of Piper guinensis (EEPG) has been studied using gravimetric, gasometric and thermometric methods. The results of the study reveals that the different concentrations of ethanol extract ofPiper guinensis (EEPG) inhibit mild steel corrosion. Inhibition efficiency of the extract is found to vary with concentration, temperature and period of immersion....
Modeling and theoretical calculation of liquid heat capacity of alcohols and aldehydes using QSPR
November 2008
The most important domain part of chemometrics is the studies which relate the properties of molecules to their structural characteristics. In this work we use the quantitative structure – property relationship (QSPR) for providing a linear model for predicting the heat capacity of alcohols and aldehydes in liquid phase at 298 K. To perform this research, a set of 32 alcohol and aldehyde as data series was...
Development of a sensitive spectrophotometeric method for determination of copper
October 2008
Simple and rapid spectrophotometeric procedure have been established for quantitation of Cu (II). This method is based on the reaction between alizarin red S and boric acid in the solution of pH 8.5 to produce a red complex which place between organic and aqueous phases. In presence of Cu (II), the complex of alizarin red S and boric acid is dissociated and new complex between alizarin red S and metal ions formed...
Impact assessment of effluent discharge on physico-chemical parameters and some heavy metal concentrations in surface water of River Challawa Kano, Nigeria
October 2008
In order to understand bioavailability of heavy metals in water, surface water samples were collected from River Challawa, Nigeria, with the view of determining the effect of industrial effluents on the water quality of the river. The fractional concentration of heavy metals (Cd, Cr, Pb and Zn) in water were analysed using Atomic Absorption Spectrophotometer. The water samples were also analysed for...
Azodyes as corrosion inhibitors for dissolution of C-steel in hydrochloric acid solution
September 2008
The effect of some mono azo dye compounds on the dissolution of carbon steel (type L-52) in 2M hydrochloric acid solution was studied using weight loss and galvanostatic polarization techniques. The inhibition efficiency was found to increase with increasing inhibitor concentration and decreasing temperatures. Inhibition was explained by formation of insoluble complex adsorbed on the metal surface. The adsorption...
Binding pattern of ferrocyphen upon interaction with cetyltrimethyl ammonium bromide in the presence of urea
September 2008
Cetyltrimethylammonium bromide (CTABr) have been titrated against Ferrocyphen (Dicyano-bis-(1, 10-phenanthroline) iron II complex) in aqueous solution as a function of urea concentration which gave a sigmoidal binding isotherm. A simple method was introduced for resolution and characterization of binding set on the basis of binding capacity concept to give hill coefficient > 1.0. Hill coefficient greater than one are...
Perfluorooctanoic acid and perfluorooctane sulfonate in Nile Perch and tilapia from gulf of Lake Victoria
August 2008
A report of the levels of Perfluorooctane Sulfonate (PFOS) and Perfluorooctanoic Acid (PFOA) in the fish from Lake Victoria is presented. Two fish species namelyLates niloticus (Nile perch) and Oreochromis niloticus (Nile tilapia) were obtained from Winam gulf of Lake Victoria, Kenya and analysed for PFOS and PFOA in muscles and liver using LC/MS/MS. Concentrations value of PFOS in Nile perch muscles of...
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