African Journal of
Pure and Applied Chemistry

  • Abbreviation: Afr. J. Pure Appl. Chem.
  • Language: English
  • ISSN: 1996-0840
  • DOI: 10.5897/AJPAC
  • Start Year: 2007
  • Published Articles: 357

AJPAC Articles

Organotin dithiobiurets as corrosion inhibitors for mild steel-dimethyl sulfoxide containing HCl

February 2011

Corrosion inhibition studies of mild steel in dimethyl sulfoxide containing HCl have been performed at 25°C using dithiobiurets and their triphenyltin- and dibutyltin complexes as inhibitors. The inhibition efficiency (IE) of these compounds was evaluated by electrochemical polarization technique. Among the ligands, best performance was exhibited by ethoxyphenyl derivative. The IE values of the ligands enhanced...

Author(s): R. B. Rastogi, M. M. Singh, K. Singh and M. Yadav

Characterization of caffeine and determination of caffeine in tea leaves using uv-visible spectrometer

January 2011

In this research, characterization of pure caffeine and the method for determination of caffeine content in twelve commercial tea leaves have been reported using UV-visible spectrometer. The optical transition properties of caffeine were measured in different solvents (dichloromethane, water, chloroform and ethyl acetate). The results show that, caffeine has highest optical transitions in dichloromethane than the other...

Author(s): Tadelech Atomssa and A.V. Gholap

Synthesis of 4-(2-Indenylethyl)morpholine and their cationic transition metal complexes

January 2011

The amido tethered ligand 4–(2–indenylethyl)morpholine (6) have been prepared in high yield (71%). All the compounds were fully characterized by NMR, IR, Mass Spec. and Microanalysis. Treatment of the lithio salt of (6) with TiCl4:2THF in THF afforded the new complex 4–(2–indenylethyl)morpholinetitanium dichloride (7a) in 26% yield as viscous green oil while, treatment with ZrCl22THF gave...

Author(s): Gloria Ukalina Obuzor and Brian L. Booth

Kinetic approach to the mechanism of the redox reaction of malachite green and permanganate ion in aqueous acidic medium

December 2010

The redox kinetic and mechanistic studies of the reactions of malachite green (MG+) and MnO4– were carried out in aqueous acidic medium, at a temperature of 32.5 ± 0.5°C; ionic strength, m = 0.50 mol dm–3 (Na2SO4), [H+] = 5.00 x 10–3 mol dm–3 (H2SO4). In the stoichiometry, one mole of malachite green was consumed by one mole of MnO4–. The...

Author(s): Y. Mohammed, J. F. Iyun and S. O. Idris

The potential of secondary metabolites in plant material as deterents against insect pests: A review

December 2010

The potential of using plant material as deterrent against pest in crops, on the field and during post-harvest period, is a study that is presently gaining acceptance as a result of the indiscriminate use of chemical pesticides which has given rise to many well-known problems, including genetic resistance of pest species, toxic residues in stored products, increasing costs of application, hazards from handling and...

Author(s): M. M. Hassan Adeyemi

An efficient synthesis and DNA binding interaction study of some novel heterocyclic fused-pyarzolequinolines: A potent antimicrobial agent

December 2010

In the present paper, the synthesis of 3-(5-phenyl-4,5-dihydro-1H-pyrazol-3-yl)quinolin-2-ol (2a)/(3a) and 3-(2-hydroxyquinolin-3-yl)-5-phenyl-4,5-dihydro-1H-pyrazole-1 carbothioamide(4a) were prepared according to Claisen-Schmidt condensation, viacondensation of 2- hydroxyquinoline-3-carbaldehyde with ketones. Then finally, α, β-unsaturated ketone (3) reacts with hydrazine hydrate,...

Author(s): Devappa S. Lamani, Kallam R. Venugopala Reddy and H. S. Bhojya Naik

Studies on some diazo coupled products of chromium(III) chelates of acetylacetone and benzoylacetone

November 2010

A number of diazo coupled products of chromium(III) chelates of acetylacetone and benzoylacetone were prepared by using some aryl diazonium ions. The aryl diazonium ions of 4-chloro, 4-bromo, 2,5-dimethoxy, 4-nitro and 1-naphthyl were synthesized by diazotization of respective aniline groups. The prepared diazo coupled products were characterized on the basis of their analytical data, magnetic moment, 1H NMR...

Author(s): Abul Kalam Md. Lutfor Rahman, M. B. Hossain, M. A. Halim, D.A. Chowdhury and M. A. Salam

Evaluation of Lead, Cadmium and Chromium in Tilapia fish obtained from Makoko and Carter Bridge Rivers in Lagos, Nigeria

November 2010

Most of the fresh water fish consumed in Nigeria comes from the Southern part of the country. The major aim of this study was to evaluate the heavy metal concentrations of Tilapia fish (Tilapia orechromis) of Makoko and Carter Bridge Rivers, thereby conducting a health risk assessment of these fishes. Heavy metal analyses were carried out by atomic absorption spectrophotometry (AAS). Lead concentrations...

Author(s): O. E. Bolawa and G. O. Gbenle

Synthesis of novel 2-quinolone derivatives

November 2010

In this work, N-amino quinoline-2-one (2) has been synthesized by the reflux of coumarin (1) with hydrazine hydrate (99%) in ethanol for 12 h. The azomethines (3-6) were prepared from the corresponding aryl aldehydes and ketones. Tetrazine derivative (7) was prepared from the reaction of compound (2) with CS2 and hydrazine hydrate in the presence of potassium hydroxide. However, the reaction of compound (2) with thiol...

Author(s): Redha I. H. Al-Bayati and Mahdi F. Radi

Characterization of colour from some dye-yielding plants in Uganda

November 2010

Dyes from nine selected dye-yielding plants namely Albizia coriaria (bark), Vitellaria paradoxa (bark), Curcuma longa Linn (roots), Indigofera arrecta (leaves), Syzygium cordatum (bark), Morinda lucida (bark), Morinda lucida (roots), Rubia cordifolia (roots),Mangifera indica (bark) and Justicia betonica (leaves), collected from...

Author(s): P. A. G.  Wanyama, B. T. Kiremire, P. Ogwok and J. S. Murumu

Phytochemical studies and pharmacological investigations on the flowers of Acacia arabica

November 2010

Fresh flowers of Acacia arabica willd were extracted with 80% alcohol and the concentrated extract was fractionated in the usual way. The ethyl acetate fraction was found to contain isoquercetin. The structure was characterized by UV, NMR, Paper Chromatographic and Chemical studies. The yellow pigment was found to contain promising results with respect to acute and chronic anti-inflammatory studies. It also...

Author(s): A. Rajendran, M. Priyadarshini and D. Sukumar

The ground state structure and properties of erythritol in gas phase and in different solvents: A DFT / SC-IPCM approach

October 2010

Quantum mechanical study of the ground state structure and properties of erythritol was carried out in gas phase and in different solvents at the hybrid B3LYP DFT level with complete geometry optimization and varying basis sets [6-311G (d,p) and 6-311++G (d,p)] in order to provide detailed information of the model molecule in solvents of low, medium and high dielectric constant. It was found that the molecule is...

Author(s): D. De, S. Dalai and B. R. De

Synthesis and characterization of a novel ionic liquid (TBA-AMPS) and its applications in Mannich condensation reactions under solvent free conditions

October 2010

This paper deals with the synthesis and characterization of a novel ionic liquid using green chemicals such as tetra-butyl ammonium chloride (TBA) and 2-acrylamido-2-methylpropanesulphonate (AMPS) via an anion metathesis reaction and characterization by 1H-NMR technique. Also, this ionic liquid was used to catalyze Mannich reactions under solvent free conditions to afford the corresponding β- amino...

Author(s): A. Rajendran and M. Priyadarshini

Solvent effects and photophysical studies of ADS560EI laser dye

October 2010

The ground state (μg) and the excited state (μe) dipole moments of a laser dye ADS560EI is estimated in various solvents by Lippert, Backshieve, Kawski-Chamma-Viallet, McRae and Suppan equations using the variation of stokes shift with the solvent dielectric constant and refractive index. The excited state dipole moments were also calculated by using the variation of stokes shift with microscopic solvent polarity...

Author(s): U. S. Raikar, V. B. Tangod, B. M. Mastiholi and S. Sreenivasa

Natural rubber/organoclay nanocomposites: Effect of filler dosage on the physicomechanical properties of vulcanizates

October 2010

Natural rubber/organoclay nanocomposites of varying filler loading [2 to 10 per hundred rubber (phr)] using derivative of tea (Camellia sinensis) seed oil were prepared by melt intercalation. Effects of filler dosage on the physicomechanical properties of the natural rubber (NR) vulcanizates were examined. Results of the mechanical properties indicates that tensile strength and tear properties of the modified...

Author(s): L. E. Yahaya, K. O. Adebowale, A. R. R. Menon, S. Rugmini, B. I. Olu-Owolabi and J. Chameswary

Comparative phytochemical and antimicrobial screening of some solvent extracts of Samanea saman (fabaceae or mimosaceae) pods

October 2010

Antimicrobial activity of distilled water (DE), methanol (ME), ethanol (EE) and ethyl acetate (EAE) extracts of Samanea saman pods was investigated by well-diffusion method against five pathogenic organisms: Bacillus subtilis (B. subtilis), Staphylococsus aureus (S. aureus), Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa) and Candida albicans (C. albicans). Only ME showed measurable...

Author(s): Obasi Nnamdi L., Egbuonu Anthony C. C., Ukoha Pius O. and Ejikeme Paul M.

Antioxidants: Its medicinal and pharmacological applications

August 2010

Antioxidants are essential and important for plants and animals’ sustenance. They are substances that protect cells from the damage caused by unstable molecules known as free radicals. The sources and origin of antioxidants which include fruits and vegetables, meats, poultry and fish were treated in this study. The types of antioxidants such as Ascorbic acid, glutathione, melatonin, tocopherols and tocotrienols...

Author(s): A. A. Hamid, O. O. Aiyelaagbe, L. A. Usman, O. M. Ameen and A. Lawal

Synthesis of polymethyl methacrylate (PMMA) by batch emulsion polymerization

August 2010

Poly (methyl methacrylate) was synthesized by batch emulsion polymerization with Methyl Methacrylate as the monomer potassium peroxo-disulfate as the initiator, sodium stearate as the emulsifier and distilled water as a medium. The kinetics of free radical polymerization was studied. The kinetics has been modeled, assuming homogeneous nucleation and the resulting equation were solved using Runge-kutta method. Degree of...

Author(s): Parul Arora, Rohit Jain, Kunal Mathur, Ashish Sharma and Alok Gupta

The inhibitive effect of Solanum melongena L. leaf extract on the corrosion of aluminium in tetraoxosulphate (VI) acid

August 2010

The effect of Solanum melongena L. leaf extract on the corrosion of aluminium in 0.5 M H2SO4 was investigated by using the gravimetric technique. It was shown that the presence of S. melongena L. leaf extract inhibited the corrosion of aluminium in the test solutions and that the inhibition efficiency depended on the concentration of the plant extract as well as on the time of exposure of the...

Author(s): Ihebrodike Maurice Mejeha, Anthony Azubuike Uroh, Kelechukwu Bierechi Okeoma and Gregory Amajuoyi Alozie

Remediation of arsenic from water/waste water using engineered carbon (EC)

August 2010

In the arena of eco-toxicological world, Arsenic pollution is a matter of alarming concern. Intake of arsenic contaminated water having concentration above the permissible limit causes Arsenic poisoning in living beings. In the present study, a batch mode lab. experiment was done using adsorption technology. Here, engineered carbon (EC) was used for remediation of arsenic from water/waste water. A significant amount of...

Author(s): Anuj Kumar Shrivastava

1H and 31P–NMR monitored cross-metathesis reaction of octavinylsilsesquioxane hybrid nanocomposite with ruthenium carbene: Possibility for multifunctional octasilsesquioxane derivatives

August 2010

Cross metathesis reaction of octavinylsilsesquioxane 1 with Grubb’s carbene 2 in CDCl3 has been monitored by 1H – and 31P – NMR spectroscopy. Reaction in the presence of excess 1 afforded a ruthenium alkylidene resonance attributable to a monofunctional derivative of 1, while in the presence of excess 2, a tetrafunctional derivative resulted as determined by 1H - ,31P – NMR...

Author(s): Enock O. Dare

Kinetics of thermal substitution reactions of some Chromium (III) -alkyl amine complexes in mixed solvent media

July 2010

Molecular dynamics of the aquation reactions of the complexes [Cr(en)2Cl2]Cl, [Cr(tn)2Cl2]Cl, [Cr(tetren)Cl]Cl2, [Cr(pn)2Cl2]Cl, [Cr(trien)Cl2]Cl and [Cr(dien)Cl3] have been extensively studied in mixed solvent media. Kinetics and thermodynamic parameters have been evaluated and the results are interpreted carefully in the light of statistical and regression models.   Key words: Cr (III) complexes,...

Author(s): A. Rajendran and K. Anbalagan

Gas chromatography – mass spectrometry analysis of the hexane extract of Calliandra portoricensis and its antimicrobial activity

July 2010

Calliandra portoriscensis is widely used in traditional medicine preparation in South western part of Nigeria for the management of sickle cell crisis and other health challenges. Analysis of the hexane extract of C. portoricensis by GC-MS revealed 14 – methyl methylpentadecanoate as the major component. Other fatty acids/fatty acid methyl esters detected were hexadecanoic acid,...

Author(s): A. T. Orishadipe, J. I. Okogun and E. Mishelia

SEM Characterization of the mass transfer of Cr(VI) during the adsorption on used black tea leaves

July 2010

This study presents the mass transfer mechanism of Cr(VI) during the adsorption on used black tea leaves (UBTLs) as a low cost biosorbent. Batch adsorption experiments were conducted in acidic media with different particle sizes of UBTLs and Cr(VI) concentrations, and the results were verified with different transport models to elucidate the mass transfer mechanism. Scanning electron microscope (SEM) and X-ray...

Author(s): M. A. Hossain, M. Kumita and S. Mori

Design, synthesis and bioassay of novel coumarins

June 2010

In Iraq like most third world countries, attempts to discover new antibiotic drugs derived from coumarins moreover develop the branch of applied in organic chemistry. Novel coumarin derivatives were synthesized in a good yield through converting lacton to lactam and study the biological activity of the synthesized compounds. Coumarins were characterized by elemental analysis, FT-IR, 1H-NMR and UV/visible spectra....

Author(s): Redha I. Al-Bayati, Ahmed A. Hussain Al-Amiery and Yasmien K. Al-Majedy

Surface modification with copper by electroless deposition technique: An overview

June 2010

Surface behaviour is very important for which substrate surface preparation is emphasized in electroless deposition process. It directly or indirectly affects surface behaviour as well as the kinetics of electroless deposition process. So far as mechanism is concerned, it proceeds in an electrochemical pathway. The electrochemical approach provides clarity of the mechanism by studying independently the partial anodic...

Author(s): K. G. Mishra and R. K. Paramguru

Applicability of an ionic liquid in the removal of chromium from tannery effluents: A green chemical approach

June 2010

The task specific ionic liquid tricaprylmethyl ammonium thiosalicylate proved to be an excellent extraction agent for chromium from aqueous solution. Chromium was removed from tannery effluents to a greater extent than the conventional methods; using the water insoluble, thiol containing task specific ionic liquid.             Key words: Task- specific...

Author(s): A. Rajendran

Palladium (II)-triphenylphosphine-arylazoimidazole complexes: Synthesis and spectroscopic characterization

June 2010

Reaction of [Pd(PPh3)2Cl2/Br2] with AgOTf in dichloromethane followed by addition of ligand leads to [Pd(PPh3)2(OSO2CF3)2] and then [Pd(PPh3)2(RaaiR)](OSO2CF3)2 [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]. 31P...

Author(s): P. Byabartta

Synthesis of nano-nickel by a wet chemical reduction method in the presence of surfactant (SDS) and a polymer (PVP)

May 2010

Nano-sized nickel particles have been synthesized by a bottom-up approach, using hydrazine as the reducing agent in the presence of an anionic surfactant - sodium-dodecyl sulphate (SDS). The effect of adding a cationic polymer -polyvinylpyrrolidone (PVP) with an anionic surfactant has been studied at two different temperatures; the rate of reduction increased as the reaction temperature was increased from 60 to...

Author(s): K. M. A. Haque, M. S. Hussain, S. S. Alam and S. M. S. Islam

Kinetics study of fibrinogen adsorbed on titanium powder

May 2010

A kinetics study of fibrinogen adsorbed on titanium has been investigated by means of spectrophotometer of the type developed for micro-enzyme linked immune-sorbent assay determination. Implants invoke inflammatory responses from the body and an attempt to alleviate the problem caused by the adsorption of protein on artificial implants mostly used in the medical, informed this study. The experimental isotherm data were...

Author(s): S. K. Omotugba, J. A. Lori, E. J. Ekanem and A. J. Kagbu

A study on the anticancer activities of ethanolic curcumin extract

May 2010

In Iraq like most third world countries, attempts to extract, identify and study the anticancer activity of the active components of plants and use it as drugs. Curcumin[(1E,6E)-1,7-bis(4-hydroxy-3-methoxyphenyl)hepta-1,6-diene-3,5dione] is the major yellow pigment extracted from turmeric, a commonly used spice, derived from the rhizome of the plant Curcuma longa. In India and Southeast Asia, turmeric has long been...

Author(s): Jasim Hilo Naama, Ali A. Al-Temimi and Ahmed A. Hussain Al-Amiery

Redox and spectral behaviour of copper (II)-chloro and bromo complexes in some nonaqueous solvents

April 2010

The redox behaviour of 3 × 10-3 M each of CuCl2.2H2O and CuBr2.H20 have been investigated at Platinum (Pt) electrode and 1 × 10-3 M CuCl2.2H20 at glassy carbon (GCE) electrode in dimethylformamide (DMF), dimethylsulfoxide (DMSO), acetonitrile (AN) and ethanol/0.1 M tetrabutylammonium perchlorate (TBAP) using cyclic voltammetry. For CuCl2 System, Epc1 and E0 are more positive, ∆Ep...

Author(s): E. J. Ukpong, N. W. Akpanudo and J. Prasad

Biotransformation of n – phenyl cyclohexenylimide and 3, 5 – dinitrobenzoic acid

April 2010

N - phenyl cyclohexenylimide and 3,5 - dinitrobenzoic acid were subjected to biotransformation on maize fermenting system. These compounds were left for two weeks in the fermenting system and later extracted with a mixture of n - hexane, diethyl ether and ethanol. The TLC of the biotransformed products were carried out. The structures proposed for the isolated biotransformed products were based on FT - IR and NMR...

Author(s): O. A. Owolodun and G. A. Olatunji

Dynamical behavior of coumarin compounds in alcohol solvents

April 2010

Dynamical behavior of 3-(2-Benzimidazolyl)-7-(DiethylAmino) coumarin [coumarin7 (C7)] and 3-(2-N-Methylbenzimidazolyl)-7-N, N-diethylamino coumarin [coumarin30 (C30)] laser dyes have been examined in methanol as a function of temperature. It is observed that, the rotational motion of probe molecule in methanol solvent increases as the temperature increase. We also investigated that, C30 rotates faster than C7 in the...

Author(s): U. S. Raikar, V. B. Tangod, C. G. Renuka and B. M. Mastiholi

Analysis of heavy metals concentration in road sides soil in Yauri, Nigeria

March 2010

Assessment of seasonal variation in physiochemical properties and concentration of the heavy metals in road side soil in Yauri, was undertaking during the two major seasons of Nigeria. This was done to determine the environmental pollution status of the soil at the road side. Soil samples collected during the 2007/2008 rainy and dry seasons were treated and digested using microwave acid digestion methods. The heavy...

Author(s): M. I. Yahaya, G. C. Ezeh, Y. F Musa and S. Y. Mohammad

A study of the biological activities of Avena sativa extracts

March 2010

In Iraq like most third world countries, attempts to extract, identify and study the activity of the active components of plants and use it as drugs. The use of herbal medicine predates the introduction of antibiotics and predates social, economic and religious barriers. The extract of the herb Avena sativa L. (Gramineae), from Iraq, was done by using of 70% ethanol as a solvent, the study the antimicrobial...

Author(s): Ahmed A. Hussain Al-Amiery, Ali A. Al-Temimi, Raghda I. Wagaa and Hussain Abood

Chemical composition and cytotoxicity of the essential oils of Crinum ornatum (Ait.) Bury

March 2010

The bulbs of Crinum ornatum were collected, dried and grounded. The powdered samples were subjected to distillation using a hydro-distiller (all-glass clevenger apparatus) to extract the essential oil present in the plant samples. GC and GC/MS analysis were carried out on the essential oil and was found to contain 18 compounds; hydrocarbons being the dominating group of compounds.  They are...

Author(s): G. K. Oloyede, I. A. Oladosu and A. F. Shodia

Inhibition effects of some plant extracts on the acid corrosion of aluminium alloy

February 2010

Corrosion inhibition of aluminium alloy (AA3003) in 0.5 M HCl by extracts of selected plants was investigated using gravimetric technique at 30 and 60°C. The studied plant materials include extracts of Euphorbia hirta and Dialum guineense. The results indicate that all the extracts inhibited the corrosion process in the medium by virtue of adsorption and inhibition efficiency improved...

Author(s): L. A. Nnanna, B. N. Onwuagba, I. M. Mejeha and K. B. Okeoma

Determination of heavy metal pollutants in street dust of Yola, Adamawa State, Nigeria

February 2010

Contamination of the environment by heavy metals is a phenomenon of global importance today. When present in high concentrations in the environment, heavy metals may enter the food chain from soils and result in health hazards. This study is aimed at determining the elemental concentrations of heavy metal pollutants that may be present in street dust samples in Yola, Adamawa State, Nigeria. Dust samples...

Author(s): D. Y. Shinggu, V. O. Ogugbuaja, I. Toma and J. T. Barminas

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...

Author(s): S. A. Osemeahon, I. I. Nkafamiya, C. Milam and U. U.  Modibbo

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...

Author(s): S. Tajammul Hussain, Rafia Naheed, Amin Badshah and Tariq Mehmood

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...

Author(s): A. O. James and O. Akaranta

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...

Author(s): A. E. M. Saeed and N. M. A. Omer

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;...

Author(s): R. G. Ayo, J. O. Amupitan, I. G. Ndukwe and O. T. Audu

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...

Author(s): A. O. James and O. Akaranta

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...

Author(s): Ahmed A. H. Al-Amiery, Yasmien K. Al-Majedy, Sallal A. Abdulhadi and Ali H. Sadoon

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,...

Author(s): Victor O. Njoku and Chidi Obi

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...

Author(s): Abebe Belay and A. V. Gholap

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...

Author(s): Hamid Shakoori Langeroodi and Abolfazl Semnani

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...

Author(s): F. A. Adekola, A. A. Baba, R. B. Bale, N. Abdus-Salam, O. A. A. Eletta and F. T. Olajide

Page 6 of 8, showing 50 records out of 357 total, starting on record 251, ending on 300