School of Physical Sciences

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Open Access
Optimization of biodiesel development from non-edible indegenous feedstocks in Nigeria
(Conscientia Beam, 2019-08-07) Nwoko, Christopher Ikpe Amadi; Nkwoada, Amarachi Udoka; Ogu, Helen Ugochi
This study investigated the transesterification of Rubber seeds (Hevea brasiliensis), Avocado Pear seeds (Gratissima persea), and Nipa Palm Kennel seeds (Nypa frutican) locally sourced from Nigeria as an adsorbate for the esterification reaction of oleic acid with methanol. Reaction was catalysed by potassium hydroxide (KOH) to form methoxide oleate (biodiesel) adsorption from aqueous solution in batch model for the production of biodiesel. The results obtained showed that rubber seeds oil (RSO), Avocado pear seeds oil (APO) and Nipa palm kernel seed oil (NPKO) oil gave maximum biodiesel yields at 0.9 % w/v, 0.1 % w/v and 0.1 % w/v catalyst concentration respectively. Their biodiesel yields were 88.0 %, 92.0 % and 96.7% respectively. They recovered biodiesel were characterized as an alternative fuel via specific gravity, viscosity, acid value, flash point and cloud point. The results obtained showed that the specific gravity for RSO (0.886 kg/m3), APO (0.876 kg/m3) and NPKO (0.850 kg/m3)were fairly significant at temperature of 25 oC to other conventional petroleum diesel ASTM D 975, standard biodiesel ASTM D975, and standard biodiesel ASTM 6751 and EN14214.
Open Access
Proficiency of graphene oxide in adsorption of Zn(II) ions from aqueous solution
(Iranian Chemical Society, 2019-06) Udoka, N. A.; Kenechukwu, E. C.
The efficient adsorption of metals on graphene oxide is often affected by the preparation method. Graphene oxide was prepared using a typical modified Hummers method for adsorptive removal of Zn2+ from aqueous solution. The experimental data were fitted into the Langmuir isotherm. The reaction was irreversible, but had a small energy of adsorption which was indicated by Freundlich isotherm model. Tempkin model and Dubinin Radushkevich revealed a physical adsorption process driven by a slow adsorptive process. The Pseudo 2nd order had the best correlation coefficient at 0.9958 while Langmuir was 0.9545. Elovich function indicated a non-spontaneous reaction, while the intra-particle diffusion was not the rate-determining step. The slow adsorption rate in pseudo 1st order correlated with the small adsorption energy shown by the Freundlich isotherm, and also correlated with the small boundary layer thickness shown by intra-particle diffusion. All adsorptive functions showed that some other competing mechanisms should exist. XRD showed an increased number of graphene layers, d-spacing and improved crystallite size. FTIR data showed the oxygen-containing groups on the graphene oxide surface. The study showed that the prepared graphene oxide could efficiently adsorb Zn2+, and that the adsorption is affected by the method of synthesis.
Open Access
Physicochemical analysis and mineralogical composition of Enugu coal In Nigeria for potential utilization
(U. P., 2017) Nwoko, Christopher Ikpeamadi; Nkwoada, Amarachi Udoka; Onu, Uchenna Lynda
The abundance of coal in certain regions of Nigeria had been described as an alternative energy solution. The potential information obtained from the physicochemical and mineralogical characterization of coal samples in such regions has enabled scientist and government to make well informed decisions. Coal samples were obtained from Okpara Mine in Enugu state Nigeria and subjected to proximate, ultimate and mineralogical analyses. The results showed that the coal had uneven particle distribution with higher content of fixed carbon and lower amount of hydrogen and volatile matter. The mineral analyses showed that the coal was rich in silicon and aluminum. The rank was bituminous coal that can be utilized for power generation, steel industry, glass manufacturing and thermite process
Open Access
Phytoextraction and risk assessment synergy of three edible plants in mining area
(U. P., 2018-08-11) Nwoko, C. I. A.; Nkwoada, A. U.; Onu, L. U.; Njoku, P. C.; Ogbonnaya, D. O.
The phytoextraction and risk assessment synergy of Arachis hypogea (groundnut), Zea maize (Corn) and Citrullus colocynthis L. (Melon) was investigated at a mining area contaminated with Cd, Cu, Pb and Zn heavy metals. The metal concentrations in plant matter and soil were determined using AAS. The average pH at 5.2 showed a slightly acidic soil while the total organic content and electrical conductivity were low. The studied metals exceeded the Nigerian FEPA guidelines as well as EU threshold values at the sites. Increase in Cd concentration in the North and South caused a corresponding decrease in plant yield. The maize appreciably accumulated more Pb than melon and groundnut. The phytoplants at the West sampling point accumulated more Zinc and melon grown at the west accumulated highest zinc concentrations of up to 1100 mg/kg. The Presence of Cu metal at low concentrations favoured an equivalent increase in weight of harvested groundnut seed. The Coefficient of Variation (CV) showed a correlation that hyperaccumulators had equivalent higher CV distribution. The values of Cd, Cu and Pb exceeded the Health Risk Index value of 1 in all the three edible phytoplants. The Cd demonstrated the lowest Bioconcentration Factor of (0.03) within the sampling area, among studied metals and the three edible plants. Thus Target Hazard Quotient (THQ) results agreed with the Daily Intake of Metals (DIM) results, that consumption of any of the three edible plants are unsafe and poses a health risk to locals; hence, the synergy of THQ and DIM in evaluating experimental data is detected in this study.
Open Access
Novel linearized kinetic modeling of starch hydrolysis
(U. P., 2017-06-09) Nwoko, Christopher Ikpe Amadi; Nkwoada, Amarachi Udoka; Ihuoma, Peterclever Chidi
The hydrolysis of starch into glucose by acid and enzyme techniques has recorded higher glucose recovery and optimization of processes, but lacks the fitting of the results into a kinetic linear model. The application of kinetic linearized model effect of temperature on pH and acid concentration during hydrolysis of starch into glucose was studied. The experiment was conducted at different durations using reported preparatory techniques and average values of triplicates were reported. The maximum glucose yield of 18.20 mg/ml was observed on 4 hours at 60°C from acid hydrolysis and similarly observed at 4 hours at 100°C for enzym e hydrolysis. The lowest glucose yield of 10.0 mg/ml and 11.1 mg/ml were both recorded at 30 minutes duration for acid and enzyme hydrolysis respectively. The correlation coefficient of acid hydrolysis when starch was hydrolyzed for 2 hours at 80°C had a value of 1 (line of best fit) while the w eakest linear relationship (0.715) was obtained was in enzymatic hydrolysis when starch was hydrolyzed at 4 hours for 80°C Hence, the highest glucose yield was not automatically the most efficient process. The linear model equations showed that acid hydrolysis of starch had a positive energetic interaction while enzymatic hydrolysis had a negative energetic interaction. The slope and intercept of acid hydrolysis were all positive and indicated a positive relationship with parameters. All enzymatic hydrolysis had negative slope and indicated inverse relationship with the parameters. Therefore, the model allows researchers to make well interpretations of their results using linearized kinetic model.
Open Access
Mineralogical and physicochemical assessment of Ihioma coal in Imo State of Nigeria
(2016-12) Nwoko, C. I. A.; Onyedika, G. O.; Nkwoada, A. U.; Anyanwu, G. C.
The physicochemical characterization of coal samples from deposits provides mineral distribution and composition data for utilization by scientists and policy makers. The characterization of coal samples of Ihioma coal deposits in Imo state, Nigeria was performed using proximate and ultimate analyses. XRD and ICP-AES were used to characterize the coal samples for potential energy utilization. Proximate analyze determined fixed carbon content and volatile matter to be 51.5% and 38.5% respectively, an indication of a good coking material. The carbon % in the ultimate analyses was at 64.6% while O2, H2, N2 and S were all below 5% which showed the coal potential to emit lower emissions. ICP-AES chemical composition determined SiO2 to be the most abundant followed by Na2O. The XRD peaks classified Ihioma coal as having Quartz, Albite and Haematite. Material mapping by XRD showed that Al and Si were evenly distributed while S, Co and Fe were unevenly distributed. Thus Ihioma coal has features of ignition and can undergo spontaneous combustion, hence a good source of thermal energy. Results also confirmed Ihioma coal as a potential material for pigments and can be utilized for ceramics, pottery and ornamentals.
Open Access
Emissions of gasoline combustion by products in automotive exhausts
(U. P., 2016-04) Nkwoada, Amarachi; Oguzie, Emeka; Alisa, Christopher; Agwaramgbo, Lovell; Enenebeaku, Conrad
Increased gasoline consumption in automotive engines have triggered the emissions of greenhouse gases (GHG) especially carbon dioxide (CO2) from automotive exhausts. These exhaust emissions depend on factors like the engine combustion design and operating conditions, fuel grade and lubricant, the state of maintenance and local road conditions and continue to affect the concentration of pollutants emitted by automotives like CO2 and unburnt hydrocarbons which are very toxic to humans, leading to environmental pollution. In pursuant of improved efficient engine and less toxic emissions, the use of gasoline blends and biofuels are not the panacea since the exhaust-gas concentration and its constituent are not indicative of the contribution of the constituent to the overall emission due to variations in exhaust-gas flow rate with different engine types and automotive sources. Moreover real-time monitoring, turbocharging technologies, fuel injection strategies and catalytic exhaust aftertreatment may reduce emissions if compared to base engines but significant risk of CO2 induced climate change continue to persist, while CO2 capture technologies such as adsorption and absorption are limited in contrast to new developments in engine and exhaust technologies that are cheaper and locally sourced and could become the next trajectory.
Open Access
Studies on adsorptive behavior of Cd2+ on graphene oxide: Alternative novel approach
(U. P., 2018-03-03) Nkwoada, A. U.; Alisa, C. O.; Enenebeaku, C. K.; Oguzie, E, E.
Certain adsorptive mechanisms and interactions often exist within linearized kinetic functions which are largely unreported. A novel inverse saturation modeling was applied to evaluate the adsorptive behavior of super-saturation, saturation, and desorptive processes on linear kinetic function plots using pseudo 1st order, pseudo 2nd order, Elovich and Intra-particle diffusion. Graphene oxide was prepared by room temperature synthesis and used as adsorbent over Cd2+ adsorbate. Batch adsorption process was conducted and four error functions were utilized. The sum of squares of the errors and Sum of absolute errors identified pseudo 2nd order as having the least deviation at 0.113 and 0.337 respectively. The modelled pseudo 1st order reaction had R2 = 0.985 while the inverse saturation model had R2 value of 0.998, both been a better data fit than non-modelled pseudo 1st order R2 at 0.917. The slower reaction kinetics in pseudo 1st order was due to supersaturation during adsorption as shown by inverse saturation point. The correlation coefficient of modeled kinetic plot of pseudo 2nd order, Intra particle diffusion and Elovich had R2 = 1. The Elovich inverse saturation plot showed that the graph was an L-isotherm type indicating progressive saturation. The rate determining step experienced by Intra-particle diffusion was accommodated by wide range of inverse saturation plots showing adsorption, supersaturation and desorption as points of greatest influence. The inverse saturation plot of pseudo 2nd order plot had absolute slope of 2.656 and large intercept of 24.815 driving it's faster reaction kinetics. Hence, the inverse saturation point modelling provided a much better interpretation of adsorptive behavior of graphene oxide adsorbent over Cd2+ adsorbate.
Open Access
Pollution in Nigerian auto-mechanic villages: A review
(U. P., 2018) Nkwoada, A. U.; Alisa, C. O.; Amakom, C. M.
The increasing number of malfunctioning automobiles with subsequent increase in emission levels and waste handling is an environmental concern in Nigeria. The spills from lubricants, gasoline, diesel and byproducts of used and spent engine oil constitute the major pollutants in auto mechanic villages in Nigeria. Its environmental pollution has been predominant through soil and groundwater contamination and also poses a major anthropogenic threat. The studied heavy metals on contaminated soil showed that studies had focused on common metals of Cu, Cd, Pb and Zn in the east and west regions, while trace metals were studied in the south and radioactive elements in the north. Statistical evaluation showed high occurrences of Cu, Cd, Pb and Zn in the four geo-political zones of Nigeria. The detrimental effects of auto-mechanic village activities were on humans and also disrupted growth and flowering of arable plants. The remediation application showed that soil type and contaminant characteristics play a major role in determining the type of remediation procedure to be applied. Hence, Nigeria should provide standard repairs and services to automobiles in-line with emerging technology and best environmental practices.
Open Access
Fluorescence lifetime investigation and characterization of dysprosium and terbium doped taggants
(JACS Directory, 2016) Nkwoada, A. U.; Officer, Simon
An investigation was made into the use of fluorescent materials called taggants that would give a better discrimination against the background interference arising from hydrocarbons and having a longer lifetime than other sources of interference. Borosilicate and tellurite glass host were doped with dysprosium and terbium rare earth elements. Their absorptions and fluorescence lifetime characterisation was used to determine their interaction and compatibility with cyclohexane and crude oil. The fluorescence lifetime test established Dysprosium doped glasses as the optimum taggants for cyclohexane and terbium doped tellurite glass as the ideal taggants in crude oil and both achieving better lifetime discriminations respectively.
Open Access
Investigation of Aba river contamination using Eichhornia crassipes as bio-indicator
(U. P., 2017-06-05) Akagha, C. I.; Ajiwe, V. I. E.; Okoye, P. A. C.; Alisa, C. O.; Nkwoada, A. U.
The seasonal variation of heavy metal contamination levels in Aba River of Abia State in Nigeria was investigated using Eichhornia crassipies. Routine sampling was performed on bi-monthly bases to cover the Nigerian Rainy season and Harmattan season. Iron (Fe) showed more abundance with maximum concentration (69.5 mg/kg) mainly in Dec/Jan at UST, PZA, ABT and DST sampling points. The lowest concentration of iron was obtained in Apr/May for UST and DST and in Oct/Nov for PZA and ABT. Manganese showed maximum concentration (7 mg/kg) in the dry season at PZA and NBL during Oct/Nov months. The lowest concentration was in Dec/Jan at UST, PZA and ABT which were Harmattan seasons. The varied concentrations of zinc (Zn) demonstrated no pattern or trend except at Oct/Nov of ABT at value of 9.7 mg/kg, while lead (Pb) metal was significantly identified during the months of Feb/March (end of Harmattan) and April/May (beginning of Rains) during the seasonal study. Chromium metal (Cr) was uniformly distributed but significant at NBL during months of Jun/Jul. Nickel (Ni) metal was detected mainly at UST, PZA and NBL at trace levels. Copper was mainly detected during rainy seasons of Apr/May and Jun/July but remained at low concentrations when compared to other metals. Hence, UST and PZA sampling points contained the most active level of heavy metals, while Harmattan season showed the highest phytochemical activity of the heavy metals. Therefore Eichhornia crassipes showed metal removal in the following order Fe > Mn> Cr > Ni > Pb > Zn > Cd.
Open Access
Natural products for materials protection: Corrosion and microbial growth inhibition using capsicum frutescens biomass extracts
(American Chemical Society, 2012-12-17) Oguzie, Emeka E.; Oguzie, Kanayo L.; Akalezi, Chris O.; Udeze, Irene O.; Ogbulie, Jude N.; Njoku, Victor O.
Extracts of the fruit of Capsicum frutescens (CF) were assessed for anticorrosion and antimicrobial activity. The anticorrosion effect of the ethanol extract on low carbon steel in acidic media was studied experimentally using gravimetric, impedance, and polarization techniques, while the antimicrobial efficacy of ethanol, methanol, water, and petroleum spirit extracts respectively against the corrosion-associated sulfate reducing bacteria (SRB), Desulfotomaculum species, was assessed using the agar disc diffusion method. CF extract effectively inhibited both corrosion and SRB growth due to the action of the phytochemical constituents present therein, including alkaloids (8.8%), tannins (0.4%), and saponins (39.2%). The corrosion process was inhibited by adsorption of the extract organic matter on the steel surface, whereas the antimicrobial effect results from disruption of the growth and essential metabolic functions of the SRB. Molecular dynamics (MD) simulations were performed to theoretically illustrate the electronic structure and adsorption behavior of the active alkaloidal constituents of CF extract, capsaicin and dihydrocapsaicin, and afforded molecular level insights on their individual contributions to the corrosion inhibiting action of the extract
Open Access
Effect of hexamethylpararosaniline chloride (crystal violet) on mild steel corrosion in acidic media
(Elsevier Ltd, 2008) Oguzie, E. E.; Njoku, V. O.; Enenebeaku, C. K.; Akalezi, C. O.; Obi, C.
The corrosion inhibition of mild steel in 0.5 M H2SO4 and 1 M HCl by hexamethylpararosaniline chloride (HMPC) was investigated using the gravimetric technique in the temperature range 303–333 K. The results indicate that HPMC inhibited the corrosion reaction in both acid media at all temperatures and inhibition efficiency increased with HMPC concentration. The inhibiting action is attributed to general adsorption of protonated and molecular HPMC species on the corroding metal surface. Adsorption followed a modified Langmuir isotherm and the Temkin isotherm, with very high negative values of the free energy of adsorption (DG0ads). An increase in temperature reduced the inhibition efficiency of HPMC in 0.5 M H2SO4 but increased efficiency in 1 M HCl. Activation parameters such as activation energy (Ea), activation enthalpy (DH*) and activation entropy (DS*) as well as the adsorption heat (Qads) were evaluated from the effect of temperature on corrosion and inhibition
Open Access
Corrosion inhibiting effect of aframomum melegueta extracts and adsorption characteristics of the active constituents on mild steel in acidic media
(Taylor & Francis Group, LLC, 2013) Oguzie, E. E.; Iheabunike, Z. O.; Oguzie, K. L.; Ogukwe, C. E.; Chidiebere, M. A.; Enenebeaku, C. K.; Akalezi, C. O.
The extract from the seeds of Aframomum melegueta (AM) was investigated as corrosion inhibitor for mild steel in aerated 1M HCl and 0.5M H2SO4 solutions using gravimetric and electrochemical techniques. AM extract was found to inhibit both the cathodic and anodic partial reactions of the corrosion process, via adsorption of the organic matter on the metal/solution interface, as described by the Langmuir as well as Flory-Huggins adsorption isotherms. Corrosion rates in all systems studied increased with rise in temperature. Increasing the temperature of the system enhanced inhibition efficiency of AM extract in 1M HCl, but decreased efficiency in 0.5M H2SO4. Molecular dynamics simulations were performed to theoretically illustrate the electronic structure and adsorption behaviour of the active constituents of the seeds of Aframomum melegueta; paradol (1-(4-Hydroxy-3-methoxyphenyl)decan-3-one) and shogaol ((E)-1-(4-Hydroxy-3- methoxyphenyl)dec-4-en-3-one) in order to theoretically evaluate their contributions to the corrosion inhibiting action of the extract.
Open Access
Adsorption and corrosion-inhibiting effect of dacryodis edulis extract on low-carbon-steel corrosion in acidic media
(Elsevier Inc., 2010) Oguzie, E. E.; Enenebeaku, C. K.; Akalezi, C. O.; Okoro, S. C.; Ayuk, A. A.; Ejike, E. N.
The inhibition of low-carbon-steel corrosion in 1 M HCl and 0.5 M H2SO4 by extracts of Dacryodis edulis(DE) was investigated using gravimetric and electrochemical techniques. DE extract was found to inhibit the uniform and localized corrosion of carbon steel in the acidic media, affecting both the cathodic and anodic partial reactions. The corrosion process was inhibited by adsorption of the extracted organic mat ter onto the steel surface in a concentration-dependent manner and involved both protonated and molec ular species. Molecular dynamics simulations were performed to illustrate the process of adsorption of some specific components of the extract.
Open Access
Antibacterial activity and identification of metabolites from the semi-purified fraction of chrysophyllum albidum leaf (African Star Apple)
(U. P., 2020) Azih, Ifeanyi; Ijezie, Magnus; Ugariogu, Sylvester N.; Akalezi, Christogonus O.
The medicinal uses of natural products especially medicinal plants have increased tremendously due to the multidrug resistance of some microorganisms and due to the availability and affordability of these plants. This study was aimed at the identification of metabolites from the fractions of Chrysophyllum albidium and their antibacterial activity. The phytochemical analysis and antibacterial analysis were done using standard methods; Harborne and Agar-disc diffusion methods, respectively. The metabolite identification was done using infra-red (IR) and gas chromatography – mass spectrometry (GC-MS). The preliminary result of the antibacterbial screening showed that the neutral metabolite possessed the highest antibacterial activity and was then chosen for the IR and GC-MS study and purified using preparative thin layer chromatography. Various fractions were obtained from the chromatographic purification and in particular N3 fraction demonstrated the highest antibacterial activity against the test microbes with the zones of inhibition indicated against the test organism as follows: Streptococcus spp (18 mm), Staphylococcus aureus (20 mm), Salmonella typhi (25 mm), Escherichia coli (20 mm) and no inhibition zone against Enterobacter cloacae. The results confirm that the plant has some antibacterial activity.
Open Access
Corrosion inhibition properties of Gongronema latifollium extract in acidic media
(U. P., 2016-06-04) Akalezi, C. O.; Ogukwe, C. E.; Ejele, E. A.; Oguzie, E. E.
Corrosion inhibition of mild steel in 1 M HCl acid solution by Gongronemena latifolium (GL) extract was investigated by weight-loss and electrochemical techniques. A significant decrease in the corrosion rate of mild steel was observed in the presence of the investigated additive and the inhibition efficiency was found to depend on the concentration of the GL extract. The potentiodynamic polarization data indicated that this additive was of mixed type, but the anodic effect was more pronounced. Nyquist plots showed that on increasing the extract concentration, the charge transfer resistance increased and double layer capacitance decreased. Adsorption of inhibitor GL extract on the mild steel surface is found to obey the Langmuir adsorption isotherm. Increase in activation energy of corrosion process in presence of GL extract indicates physical adsorption.
Open Access
Corrosion inhibition of aluminium pigments in aqueous alkaline medium using plant extracts
(Canadian Center of Science and Education, 2012) Akalezi, Chris O.; Ogukwe, Cynthia E.; Enenebaku, Conrad K.; Oguzie, Emeka E.
This work examines the efficacy and efficiency of Bucolzia coriacea (BC) and Cninodoscolus chayansa (CC) plants extracts as corrosion inhibitors for aluminum pigments using gas volumetric technique. The results obtained from this study indicate that all the extracts inhibited the corrosion process by extending the latency periods of the aluminum pigment-extract mix far beyond that of the bare aluminum pigment. Inhibition efficiency obtained was not only concentration dependent but also plant dependent and followed the order: BC>CC. A linear correlation was obtained between inhibition efficiency and duration of latency for each extract. Molecular modeling was used to evaluate the structure, electronic reactive parameters of the plant extracts in relation to their effectiveness as corrosion inhibitors.
Open Access
Gas chromatography-spectrophotometric (GC- MS) studies on therapeutic potentials of costus afer ker gawl leaves
(U. P., 2018) Ogukwe, Cynthia E.; Akalezi, Chris O.; Anukam, Basil N.; Idika, Idika D.; Awosu, Emmanuel A.
The ethanol leaf extract of Costus afer was subjected to qualitative phytochemical screening, column chromatography and GC-MS analysis to ascertain the compounds that exhibit anti-inflammatory and anti-oxidant properties as claimed by herbalists and traditionalists. The presence of Flavonoids, Saponins, Steroids, Terpenoids and Anthraquinones were indicated in the phytochemical screening. Eluent fractions from the moderately polar solvent of the column chromatography generated Gas Chromatogram that had 6 prominent peaks indicated that the prevailing compounds were oxirane hexadecyl (4.09%), n-Hexadecanoic acid(3.68%), 9-octadecenoic acid (z)- methyl ester(3.08%), 6-octadecenoic acid (z)- (13.49%) and two pentacyclic compounds identified as Cycloursan-3-ol, acetate (36.17%) and lupenone (39.50%). The two pentacyclic compounds confirmed the presence of steroids and validates the use of C.afer leaf for anti inflammatory therapy and as an antidote for acute toxi.
Open Access
Determination of the binding characteristics of dicoumarol to bovine serum abumin by UV/visible spectroscopic method
(U. P., 2020) Okoro, O. A.; Onwumere, F. C.; Enebeaku, C. K.; Akalezi, C. O.
8-Anilinonaphthalene-1-Sulfonic acid (ANS) was used as a probe to study the binding characteristics of Dicoumarol to Bovine Serum Albumin (BSA). The absorbance of ANS-BSA complex was decreased by the binding of Dicoumarol. This suggests that there is competition between Dicoumarol and ANS for the binding sites in the BSA. It means that ANS and Dicoumarol shared some of the binding sites on BSA. From the scatchard plot for the binding of Dicoumarol to BSA it is seen that Dicoumarol has three high affinity binding sites with association constants Kl=14.5245 x 106,10.6281x106,11.6811x106 respectively, and three secondary binding sites with association constants Kl =14.0084 x 10615.8816 x 106 and 19.2058x106 respectively and numerous low affinity binding sites.