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2-D ELECTRICAL RESISTIVITY IMAGING AROUND THE COLLAPSED BUILDINGS OF THE HOUSING ESTATE AT BARNAWA-NARAYI JUNCTION, KADUNA, KADUNA STATE
(2014-11) AGBO, Comfort
Resistivity method is frequently used in environmental studies. Electrical resistivity imaging survey has been carried out at the housing estate located at Barnawa-Narayi junction in Kaduna, Kaduna State in order to investigate the subsurface geological structureswhich includethe possible presence of faults, fractures, voids and clay that may pose danger to the structures that have been constructed,depth to bedrock and thickness of weathered basement (aquiferous zone). A modern and state-of-the-art field instrument, the ABEM Automatic LUND Imaging System (Terrameter SAS 1000 and ES 464) employing the Schlumberger array, was used to accomplish this task by obtaining two-dimensional resistivity data sets along seven profiles within the survey area. The acquired data were processed and interpreted using RES2DINV software to produce the two-dimensional image of the study area. The subsurface images showed that the resistivity range lies between 1 to about 1178Ωm, indicating variation in soil matrix, grain size distribution and water saturation. The near surface materials from 0 to a depth of about 2.7m constitute the top soil with relatively high resistivity values ranging from 49Ωm to 180Ωm were obtained. The decrease in resistivity ranging from 4Ωm to 98Ωm with thicknessof about 10.0m below the top soil indicates saturated soil.The fractured/partially weathered zone has resistivity ranging from49Ωm to 533Ωm with thickness between 5.0m and 17.2m. Beyond the fractured/partially weathered basement is the fresh basement with resistivity value ranging from 429Ωm to 1178Ωm with variable depth to it.This depth in profiles 2 and 4 is 17.2m and in profile 6 it is 14.8m. The basement was not reached in profiles 1,3, and 5. Itappears in form of an intrusion in profile 7 at a depth of about 6.9m.The images suggest the presence of building constraints such as fractures/zones of weakness that may constitute problems to the building foundations.However, the images have not suggested the presence of clay formations.The zones of weakness/fractures discovered within the area of study have resistivity values ranging between 49Ωm and 109Ωm which could also have led to the collapse of the buildings. The subsurface within the area of study is characterized by sharp variations in the basement relief/topography which probably led to the collapse of the buildings.
2-D ELECTRICAL RESISTIVITY INVESTIGATION OF SOLID WASTE DUMPSITE AT GONIN-GORA, KADUNA STATE, NIGERIA
(2014-05) MIKE, ASUERIMEN
Leachate effluence from refuse dumpsite is an important source of soil and groundwater pollution. Consequently, assessing the impact of Leachate is an active area of soil and groundwater research. 2-D Electrical Resistivity imaging survey was carried out at a dumpsite in Gonin-Gora area of Kaduna State, with the aim of determining how accurately electrical measurements could delineate the influx of leachate into soil and groundwater. A modern and state-of-the-art field instrument, the ABEM Automatic LUND Imaging System (Terrameter SAS 1000 and ES 464), produced by ABEM instrument AB, wasused to accomplish this task. This uses multi-core cables with takeouts at 2m intervals, having a total of 42 electrodes covering a spread of 200m. Six profiles were covered and the data were processed to display the variations of electrical resistivities using the RES2DINV software. Four of the profiles were inside the dumpsite while two profiles were outside the dumpsite.Also, one Vertical Electrical Sounding (VES) was conducted inside the dumpsite with thesame ABEM TerrameterSAS 1000,and was interpreted using computer software (IPI2win) which gives an automatic interpretation of the apparent resistivity data.The results of this survey in correlation with a Borehole log of the area revealed three layers: The topsoil, which consists ofreddish brown lateritic and sandy clay, has resistivity values between 8Ωm and 850Ωm and its thicknessvaries between 0.01 m to 7.00 m. The second layer is the weathered basement, and has resistivity values between 150Ωm and 940Ωm. Its thickness ranges between 2.00 m to 16.00 m. The resistivity of the fresh crystalline basement which forms the third layer ranges between 820Ωm to 4000Ωm. The 2D Inversion delineated contamination plumes as low resistivity zones with resistivity values ranging between 1Ωm and 27Ωm, from the ground surface to vii varying depths of 0-3 m in profile 1 and profile 4, believed to be leachate derived from decomposed waste of higher concentrations, while profile 2,profile 3 and profile 6 delineated contamination plumes withresistivity zones ranging between 100Ωm to 200Ωm, from the ground surface to varying depths, believed to be leachate from decomposed wasteof lower concentrations.There was no evidence of topsoil or groundwater contamination as revealed by the inversion model in profile 5.The VES data revealed that the area has a shallow aquifer of about 4m, indicating that the topsoil as shown in all the profiles except profile 5, and the groundwater in profiles 3 and profile 6 are contaminated.A comparison ofthe measured apparent resistivity pseudosection and the calculated apparent resistivitypseudosection resulted in a reasonably good agreement with the inverse model resistivity section. The study area has a shallow depth to Basement of 1.30m and a depth to water table of about 4m.The inverse model revealed weak zones which could be interpreted as fractures, which aid in the migration of the leachate as shown in profile 3 and profile 6.
2D RESISTIVITY INVESTIGATION OF CASSITERITE (TIN ORE) BEARING LAYER AT PINGEL VILLAGE, MAGAMA GUMAU, BAUCHI STATE, NIGERIA
(2021-05) BASHIR, Ogirma Yususf
Two dimensional geoelectric resistivity survey was conducted at the mining site in Pingel village, MagamaGumau, Bauchi state, Nigeria. The survey was undertaken to characterize the cassiterite bearing layer in the area. A test profile was conducted along a point with an exposed subsurface that reveals different layers of the earth, including that rich in cassiterite, to detect the best configuration to be used. Based on the result obtained from the test profile, the Schlumberger array proved to be a better representation of the layering of the study area. A total of five profiles were then taken and the result of the 2D resistivity survey revealed the occurrence of three to four layers in the geoelectric models. The top layer consists of earth materials with resistivity values mostly less than 120 Ωm, inferred to consist of mainly clayey sand and laterite with an approximate thickness of 4.5 m. The second layer has resistivity range of 60 Ωm to 250 Ωm and may consist of weathered and fracture rocks with cassiterite composition at approximately 7.0 m depth. The third layer is composed of highly resistive materials, generally greater than 800 Ωm, at a depth stretching beyond 7 m. The high resistivity values could be associated with the fresh basement.
A STUDY ON THE NIGERIAN NAIRA PER US-DOLLAR EXCHANGE RATE USING ARFIMA-GARCH AND ARFIMA-FIGARCH MODELS
(2023-04) AHMAD, MAIMUNA ALIYU
Autoregressive Fractionally Integrated Moving Average (ARFIMA) model is widely used in the study of long memory processes but it is not suitable for series exhibiting high periods of volatility. Exchange rate series are characterized by periods of stability followed by periods of instability in volatility which can be modeled by Autoregressive Conditional Heteroskedastic (ARCH) model. A parsimonious generalization of the ARCH model is Generalized ARCH (GARCH), but still, neither ARCH nor GARCH can handle the presence of long memory in volatility. This research investigated the presence of long memory both in mean and volatility of the Nigerian Naira per US-Dollar exchange rate series using the hybrid models of ARFIMA, GARCH and Fractionally Integrated GARCH (FIGARCH) origins. Long memory tests were carried out on fractionally differenced and volatility series. The result of GPH estimator indicated the existence of significant Long Memory in the exchange rate data. Classical ARFIMA model was fitted to the data but the results showed the presence of serial autocorrelation and ARCH effects, signifying the limitations of fitting the ARFIMA model. Hybrid ARFIMA models with conditional variance following GARCH and FIGARCH processes were then respectively fitted to the exchange rate series with much improvement in model fitting. Autocorrelation of residuals and ARCH effects were insignificant showing the adequacy of the fitted hybrid models. At the end of the research, the forecasting performance measures of the fitted ARFIMA-GARCH and ARFIMA-FIGARCH models were determined in terms of RMSE. ARFIMA-GARCH demonstrated a better performance.
ABSORPTION OF METAL IONS BY NATIVE AND MODIFIED NIGERIAN WOOL
(1979-02) NDUJI, ALEXANDER AGODI
Wool and h a i r c o n s t i t u t e a major component of e f f l u e n t materials in the tanning industry. Since they are insoluble in aqueous medium where most of the tanning processes are undertaken, it becomes necessary to i n v e s t i g a t e other sources that will convert their i n s o l u b i l i t y into a useful process and cut down the cost of production Conditioned native and modified Yankasa wool f i b r e s were treated with metal ions and the uptake was measured. The e f f e ct of metal ion uptake on the mechanical properties of the wool was a l s o determined. Yankasa wool f i b r e s impregnated with m e t a l ions were subjected to infrared spectroscopic s t u d i e s . These s t u d i e s showed that interaction between the reactive groups in wool (hydroxyl, amino,phenolic and carboxyl groups etc) and the electron d i f i c i e n t metal ions r e s u lt in complex formation. As a r e s u l t , Yankasa wool f i b r e s which h i t h e r t o are drained i n t o effluent tanks and l a t e r c o l l e c t e d and burnt, can now serve as scavengers for r e t r i v i n g expensive and toxic metal ions from i n d u s t r i a l water. Furthermore, the treatment has been found to improve the t e n s i l e strength, f l e x i b i l i t y and modulus.
THE ABSORPTION OF NAPHTHOL DERIVATIVES BY CELLULOSIC FIBRES.
(1968-07) Atanu, Emmanuel Yahaya
The azoic dyes are obtained by coupling between, a naphthalene derivative end a diazotized amine The naphthalene derivative is referred to variously as a coupling component, arylamide or by its commercial name e.g. Breathol, Naphthol, etc. It is first adsorbed onto the textile material and the desired colour developed by immersing the fibre or fabric in a solution of the appropriate diazotized amine. The depth of the shade depends mainly on the amount of coupling component adsorbed on the fibre, prior to colour development. The scope of the present work was to study the uptake of these compounds by cellulosic fibres under various conditions e.g. different alkali, salt and naphthol concentrations; temperature; and the effect of modifying the cellulose structure on absorption. It was also thought that a possible mechanism for the combination of naphthol with cellulose could be worked out and an attempt made to see if the general laws of sorption of solids from solution could be applied to the cellulose naphthol system. As an introduction to the thesis an account is first given of the structure of cellulosic fibres, describing in outline the early theories of fine structure and the concept of crystallinity and accessibility and their relation to the absorption of dyes and other molecules by cellulosio fibres. An account is also given of the principal results of previous studies on the absorption of arylamides and direct dyes by cellulose. The abaorption of free alkali (the solvent for the Naphthols) was first studied, followed by napthol absorption under various conditions by the different cellulose samples. The sain results of the present investigations indicate that: 1) the hydroxyl groups of the cellulose chain are mainly responsible for naphthol absorption as shown by the reduction in absorption when these are oonverted to carbosyl groups. 2) primary hydroxyl groups account for higher equilibrium absorption than secondary ones. 3l oxidation of the hydroxyl groups reduces absorption. 4) opening up the cellulose structure by mereerization increases considerably the absorptive capacity of cellulose. The absorption of two naphthols by standard cellulose at different starting concentrations was also studied and the results used to test several adsorption theories. Agreement was obtained for the treatment of Saruwalla and Kulkarni leading to the suggested mechanism that only the dye anions are adsorbed on specifio sites, while the sodium ions are diffusely adsorbed. The treatment adopting Hill's statistical approach also yielded a positive agreement. The concurrence of the theories tested lies in the fact that their formulation depends on the basic assumption of an initial monolayer absorption on which is superimposed a diffuse layer.
ABSTRACT EVOLUTION EQUATIONS AND THE CAUCHY AND MIXED PROBLEMS FOR SYMMETRIC HYPERBOLIC SYSTEMS
(1976-11) Olagunju, David Olarewaju
ABUNDANCE OF INDOOR RESTING MOSQUITO POPULATIONS AND PLASMODIUM FALCIPARUM INFECTION OF ANOPHELES SPP IN SETTLEMENTS AROUND THE ZARIA DAM, ZARIA, KADUNA STATE
(2014-05) MICHEAL, COMFORT
The species composition of mosquitoes resting indoors in settlements surrounding the Zaria dam, Zaria, namely: Angwan Malami, Angwan Shika and Zaria water works quarters were investigated. Mosquitoes were caught twice a month for ten months January to October (2013),by application of pyrethrium spray in rooms where tenants had slept the previous night. The total mosquito caught were first identified microscopically,the Anopheles gambiaecomplex were morphologically identified. Using the Polymerase Chain Reaction (PCR) technique, the Anopheles gambiaecomplex were identified molecularly and further assyed by Enzyme Linked Immuno-sorbent Assay (ELISA) to determine the sporozoite infection rate. Microscopically, Culex quinquefasciatus, Culex annulioris, Anopheles gambiae, Anopheles funestus, Anopheles rhodesiensis, Anopheles arabiensis and Aedes aegypti were encountered. Culex quinquefasciatuswasthe most abundant with 254 (50.2%), followed by Anopheles species 134 (26.5%.) and only a single species of Aedes aegypti 1( 0.2%) was collected in the study. Anopheles gambiaes.l samples identified by PCR (Polymerase Chain Reaction) were 104 out of which 66( 63.5%) showed the diagnostic fragment (390bp) characteristic of Anopheles gambiaes.s while 27 (26%) showed the diagnostic fragment (315bp) of Anopheles arabiensis. The other 11( 10.5%) of the sample were not amplified. The infectivity rates were 4.3% (2/46), 4.5%(1/22) and 5.1% (1/19) in Angwan Shika, AngwanMalami and Water Works Quarters respectively. The mean human biting rates were 0.84, 0.79 and 0.73 respectively while the entomological inoculation rate is 104.4.This study show An.gambiae, An.arabiensis,Culex quinquefasciatus and Aedes aegyptia abound in the study area. The infection rate, inoculation rate and human biting rate revealed during the study have incriminate An.gambiae and An.arabiensis as the main vectors offalciparummalaria in the settlements.
ACCESS AND UTILIZATION OF ANTENATAL CARE SERVICES IN FUNTUA LOCAL GOVERNMENT AREA, KATSINA STATE,NIGERIA.
(2014-07) ONAMADE, Aderonke
This research work examined the access and utilization of antenatal care cervices for women in Funtua Local Government Area of Katsina State. Data from the study was obtained from the administration of a semi-structured questionnaire. Majority of the respondents were Christian married women between the ages of 24-34 which also had their first marriage at the age of 20-24 years. This study also revealed that 86 percent of the respondents have knowledge of antenatal facilities existing in tertiary health care centers. The distance of antenatal facility 29 percent of respondents is less than 2km away from their destination with about 29 percent. The demand for antenatal care from modern health care providers appears, according to our analysis, significantly determined by economic factors such as the household living standard, the costs for the antenatal care and in particular the costs related to the distance to health care facilities. Base on findings it is recommended that pregnant women should be offered information based on the available evidence together with support to enable them to make informed decisions about their care, women with any risk factor should be properly checked and treated in order to bring about a sound delivery; all health care centers should be provided with new facility by the center or by government. All these recommendations can help both the health workers to effectively deliver their duties, and also help the pregnant women to deliver safely.
ACCESS AND UTILIZATION OF ANTIRETROVIRAL DRUGS CENTRES IN BENUE STATE, NIGERIA
(2014-10) AYOO, Nicholas Terfa
The study was conducted on access and utilization of Antiretroviral drugs centres in Benue State, Nigeria. The objectives of the study are to determine the location of ART centres, map out all ART centres, create a spatial database for ART centres, assess the distribution of ART centres in relation to people living with HIV/AIDS and to assess the utilization of ART centres. A list of ART centres for individual LGAs was obtained from Ministry of Health Makurdi. The population data was obtained from National Population Commission, which is based on 2006 National Census. The population data was used to calculate the estimated number of PLWHA in each LGA. The administrative map of the study area was collected from Ministry of Land and Survey Makurdi which served as a base map. Structured questionnaire was administered to 400 respondents. Four hundred PLWHA were randomly selected from fifteen purposively selected ART centres in the three LGAs one from each senatorial district. A global positioning System was used to obtain the geographical coordinates of ART drug Centres. ArcGIS software version 10.1 was used in conjunction with MS Excel for mapping and SSPS version 20.1 was used for statistical analysis. Point maps were then generated using ArcGIS, and then joined with other map layers so as to perform GIS analysis. GIS analysis tools used were, query analysis, overlaid analysis and nearest neighbour analysis to determine the location and distribution of ART centres, assess the spatial distribution of ART drug centres providing ART services in relation to the number of PLWHA and the distribution pattern. Comparisons were made between the distribution of ART centre with population and estimated number of PLWHA. The study reveals that, there were 46 ART drug centres in the study area with 15.2% of them located in Makurdi the State capital. The study also reveals that 93.5% of the ART drug centres are located in urban areas while 6.5% were located in rural areas. Also, 58.7% were Government owned while 41.3% were privately owned. The study further reveals that, 84.8% of ART drug centres that offered ARV services are of the secondary type of healthcare facilities while 10.9% and 4.3% were of primary and tertiary healthcare facility type. The pattern of distribution of ART drug centres in the study was done using nearest neighbour analysis in ArcMap with an index of - 1.080209 which shows the pattern does not appear to be significantly different than random with P- Value of 0.280049. The study recommends that, more centers should be cited in rural areas and LGA areas with disproportionate centers.
ACCESS TO PIPE- BORNE WATER IN KADUNA SOUTH LOCAL GOVERNMENT AREA OF KADUNA STATE, NIGERIA
(2014-11) DANIEL, Martin Nkanson
This study examined access to pipe-born water in Kaduna South Local Government Area, Kaduna State. The specific objectives were to identify the sources of household water supply and identify the presence of pipe lines facilities in each household, to establish the percentage of household with access to pipe-borne water and to determine if the quantity of pipe water supply meets demands, to assess the effects of quantity of water supply on the socioeconomic activity of householders. This study adopted a survey research. Data for this study was acquired by administration of a total of 300 questionnaires to households in five wards within the study area (60 questionnaires in each ward). Purposive sampling method was employed to select the respondents. The analysis was based on descriptive statistics and presentation. The study revealed that most of the pipe lines meant for the supply of potable water was old and inefficient despite a significant (84.4%) coverage of these pipe lines facilities. Pipe-borne water supply in the study area is not sufficient to meet the demands of the residents due to irregularity in the flow of water; 4.2% of these taps run every day, 8.8% of these taps run once a week, 11.7% of these taps run once in 3 days, 18.4% of these taps run once a year, 22.2% of these run once a month, while 37.7% water used for cooking, washing, drinking and sanitary purposes were mostly source from alternative sources that are energy and time consuming and costly to obtained. The average water consumed per person per day in the study area was 37.76 liters which is below the minimum absolute daily water needed 50 liters per person per day as stated by UNDP (2008). Consequently pipe- borne water supply in the study area do not have any significant impact on the socio-economic activities of residents as people still spent the better part of their time sourcing for water, this study therefore recommended that there should be constant monitoring of population growth rate and repairs of damage pipes and taps.
ACCESSIBILITY AND USE OF THE INTERNET BY ACADEMICS OF TERTIARY INSTITUTIONS IN NIGER STATE
(2011-06) SURAKAT, I. Fatima
This study was undertaken to explore the use of the Internet by academic staff in six (6) tertiary institutions in the Niger State. Investigation was carried out in respect of the kinds of Internet services available/accessible the various uses, preferences in the use of Internet satisfaction with the use of Internet, satisfaction with use and the provision of Internet facilities and factors influencing use. There was no study on the Internet use in Niger state necessitated this study. This study employed the survey research method which accommodates large population. There were a total of 2,634 academics in the selected tertiary institutions, out of which 600 respondents were selected for the study. However, only 572 of the lecturers completed and returned the questionnaires. The data collected were analyzed using frequency tables, mean, and percentages. The study revealed that all the selected tertiary institutions in Niger State are ICT compliant, and have Internet connectivity, although in varying degrees. Internet Chart Facilities, Discussion Groups, E-mail, and World Wide Web are available; whereas Video Conferencing, Tele-Conferencing, Internet Fax and E-Learning facilities are not available in all the tertiary institutions. The study equally revealed that some of the lecturers of these institutions have relevant technical skill for Internet use although majority of them actually utilize the E-mail and WWW facilities more than any other Internet resources. Moreover, they derive satisfaction from the utilization of Internet technology because it facilitates their teaching and research activities and finally. In spite of the under utilization of the Internet services in tertiary institutions in Niger state, academics agreed that the Internet has affected the quality and Quantity of their work. In the view of the above findings the research recommends that all the academics training/workshop on how to explore the full potential of the Internet should be organized for all academics of the institutions. The major challenges to the effective and full utilization of Internet facilities include: Erratic power supply, lack of standby generators hamper use of Internet, lack of skill on how to navigate on the Internet, etc.
ACCESSIBILITY OF INFORMATION SOURCES, SERVICES AND USE BY FARMERS OF THE UPPER BENUE RIVER BASIN DEVELOPMENT AUTHORITY, YOLA
(2011-06) KULANI, BIRINGINA HALILU
The study was undertaken to investigate the accessibility of information sources, services and use by the farmers of the Upper Benue River Basin Development Authority Yola, that cover Adamawa, Bauchi, Gombe and Taraba states of Nigeria. The study used five research questions and collected data from the sample of 1,694 out of the total population of the study which 17,720. A survey research method was adopted for the study and answer were sought on the types of information need by the farmers, the type of information resources and services available with the farmers, the types of information resources and services provided by the authority, how does the farmers use the information resources and the extent at which the information resources and services provided by the authority is assisting the farmers. The data were analyzed using frequency tables and percentage. The study revealed that the farmers operating under UBRBDA have different types of information resources on agriculture which include books, journals, radio and others. The agricultural services provided by the authority include extension services, seminars and workshops among others. The result also revealed that farmers operating under UBRBDA are satisfied with services given by the authority, which as a result they are getting good market of their produce and getting assistance toward adopting modern farming techniques. In conclusion, the study recommends that there is the need for the UBRBDA to recognize that the bulk of the rural farmers are illiterate, the extension workers should be well fluent with the language of farmers they are serving.
ACCURATE DETERMINATION OF SOURCE DISINTEGRATION RATES WITH NaI (Tl) GAMMA RAY SPECTROMETER
(2006-08) NASIRU, SA’ADU
The aim of this project is to measure the absolute activity (disintegration rates) of gamma sources. The measurement was achieved using a NaI (Tl) spectrometer. The major factors that contribute to uncertainties in the measurement were taken in to account and relevant uncertainties were propagated accordingly. The spectrometre is fully setup for disintegration rates determination. The spectrometer was calibrated for efficiency at three chosen geometries (10, 14 and 20) cm, the calibration was performed in such a way that significant factors that affect the measurements were considered. The fitted efficiency function coefficients at these chosen levels were obtained and used to write a computer program that calculates the measured absolute activity of sources and its uncertainty easily. The energy gamma range covered by the work is (59 to 1836) KeY. Therefore the work was able to integrate IAEA Quality Assurance (QA) recommendations, to simplify an accurate methodology for setting up gamma ray spectrometres, using a NaI(Tl) spectrometre. The setup spectrometre used to determine the absolute activity of two old standard calibration sources 137Cs and 60Co, the activity of the 137Cs compared well with that quoted by the manufacturer, while that of 60Co did not agree, its activity was determined to be (31319 ± 2153) BG, because it leaked prior to this work, it can henceforth be used when needed.
ADAPTING A NOSQL QUERY LANGUAGE FOR QUERYING SQL AND NOSQL DATABASES
(2017-01) WOJI, Alhamdu Shichet
Not all kinds of data can find efficient storage and manipulation in Relational (or SQL) database and neither is NoSQL database the best fit for all kinds of data. A hybrid database (a combination of both SQL and NoSQL databases for storage) is a better alternative where structured data are kept in the relational database and the rest in NoSQL database. The hybrid database comes with its challenges; among them is the necessity for the database administrator to learn the query languages of the databases that constitute the hybrid database. This research is focused on using one query language to query the hybrid database via a software layer. NoSQL (MongoDB) query language is adopted as the query language for the hybrid database in this research because it is the fastest growing query language and it is less vulnerable to injections as compared to SQL. The scope of operations supported by the software layer is limited to Create, Read, Update and Delete (CRUD) and MongoDB syntax had to be extended to cater for SQL functionalities necessary to execute CRUD operations in relational databases. The software layer was developed using Java Programming Language; it translates the MongoDB query language syntax to SQL for execution. For evaluation, both databases were fed with the same data via the software layer simultaneously and the CRUD operations were tested simultaneously on the hybrid database and the same result sets were obtained for each database; this asserts that the translation and execution were successful.
ADJOINT OPERATORS ON A HILBERT SPACE
(1997-07) SHILGBA, LEONARD KARSHIMA
Hilbert spaces are some of the ABSTRACT SPACES of interest in the abstract branch of mathematics called FUNCTIONAL ANALYSIS, The aim of the present work is to isolate linear operators on these abstract spaces (HILBERT SPACES) with the singular property of SELF-ADJ0INTNE3S for investigation. Algebraic and analytic properties of such operators come under survey. The SPECTRAL THEORY vis-a-vis these operators is explored. Furthermore, the approximate point spectrum ( oa (T) ) of a self adjoint operator T on a non-trivial separable Hilbert space examined with some proposition relating it to the POINT (EXACT POINT) spectrum ( oa(T) ) of T
ADSORPTION OF COLOUR FROM TEXTILE WASTEWATER USING ACTIVATED CARBON DERIVED FROM CASSAVA PEEL, MAIZE, GROUNDNUT AND RICE HUSKS
(2013-05) Onoharigho, Rita OKPUWHARA
ABSTRACT The adsorption of colour from textile wastewater using activated carbon derived from cassava peel, maize, and groundnut and rice husks has been studied. Commercially activated carbon is expensive, it is therefore important to find low cost precursors to be used as adsorbents especially in a developing country like Nigeria. The optimization of activating conditions of temperature, time and acid ratio for the activation of maize husk was investigated. Results showed that the optimized condition for conversion to AC is at 550°C (45min) and 60% acid ratio using phosphoric acid. All the biosorbents were prepared by chemical activation and were characterized for their BET surface area, pore volume, ash content, carbon yield, moisture content, volatile content, SEM/EDS and FTIR. Batch adsorption experiments were carried out as a function of parameters such as pH, time, adsorbent dose, particle size and adsorbate concentration. At their optimized state, among the biosorbents, maize husk activated carbon has the highest dye removal for the basic yellow dye while groundnut husk activated carbon has the highest removal for the basic green dye in the effluent. Thus, the studies show that the dye removal percentage results are an indication that the biosorbents could compare, to a good extent with commercial activated carbon and could be used as low-cost alternatives in the wastewater treatment for removal of basic dyes. According to linear regression criterion, the Freundlich isotherm model fits better than Langmuir model for dye adsorption, though both models have high fitness for this biosorption. Adsorption parameters for Langmuir and Freudlich isotherm models were examined for dye adsorption and for the validity of the models to analyse the equilibrium data, it was found that Langmuir model fits better for the removal of the basic yellow dye and Freundlich model fits better for the removal of the basic green dye contained in the effluent. vii TABLE OF CONTENTS Title Page …………………………………………………………...…………….. i Declaration …………………………………………................................................ii Certification …………………………………………..............................................iii Acknowledgements …………………………………………...................................iv Abstract …………………………………………………………………………….
ADSORPTION OF SELECTED HEAVY METALS ON ACTIVATED CARBON PREPARED FROM PLANTAIN (Musa paradisiacaL.) PEEL
(2015-02) AGBELE, IDOWU ELIJAH
Activated carbon prepared from plantain peel is used to adsorb selected heavy metals such as copper, cadmium and chromium. Heavy metals are toxic and may be found in both surface and underground water. Plantain peel which is an agricultural wastes comprising mostly of cellulose materials was activated with three activating agents (0.10M H3PO4, 0.10M NaOH and 0.10M ZnCl2 ), then latter used for the removal of these toxic metals from their aqueous solutions. Activation of plantain peel with 0.10M H3PO4 and 0.10M NaOH solutions resulted to a two-fold increase in the amounts of adsorbed Cd2+, Cr6+ and Cu2+ compared to activation with 0.10M ZnCl2.The effects of varying the particle sizes, the type of activating agents as modifiers, adsorbent dosage, agitation time, agitation speed, pH as well as initial concentration of the metal ions on the adsorption capacity of the activated carbons were determined. The linearization of equilibrium isotherms data for Langmuir and Freundlich models were obeyed over the entire range of the concentration studied, while the metal sorption closely followed Langmuir model and Freundlich model. The Langmuir isotherm has R2 values of 0.9557 for Cd2+, 0.9924 for Cr2+ and 0.9954 for Cu2+ which indicated that the adsorption behaviour was homogenously distributed. The RL value indicated favorability of adsorption capacity by adsorbent since RL value fall within 0 to 1.The characterization by FTIR showed absorbance peaks of aldehyde, amide, alkyl, hydroxyl and carboxylic functional group. Hence, these functional groups are responsible for the adsorption and activation process has an enhanced factor on the adsorption of the selected metals. The optimum conditions for the adsorption of Cd2+, Cr6+ and Cu2+ onto the activated carbon are 2.5 g of the adsorbent dosage of particle size 75 μm, 20.0 mg/dm3 of the adsorbate concentration at 60 min agitation time carried out at 150 rpm agitation speeds. At the optimum conditions the highest percentage of the metal ions adsorbed were Cr6+ (97.2%), followed by Cu2+ (90.2%) and the least was Cd2+ (53.9%).
ADSORPTION OF SIMULATED AND REAL EFFLUENTS ONTO ACTIVATED CARBON SURFACES
(2012-11) OCHOLI, ODIKE JOTHAM
Adsorption studies of simulated and real effluents was carried out with an aim to better understand adsorption processes in multi-component dye and heavy metal mixtures. Three (3) different Activated Carbon (AC) matrices were used as adsorbent: Unmodified activated carbon (UMAC), chemically modified activated carbon (CMAC) and physically modified activated carbon (PMAC). Simulated effluent systems were developed from various aqueous combinations of methylene blue (MB), methyl orange (MO), indigo carmine (IG), Pb(NO3)2 and Cd(NO3)2.4H2O. A total of twenty two (22) different simulated effluent systems were developed which were interacted with the AC matrices and three (3) textile effluents samples (TXT 1, TXT 2 and TXT 3) were also collected from a textile industry in Kaduna and used for this study. Adsorption results from single dye rate experiments revealed that the adsorption process was particle-diffusion controlled with chemisorption as the predominant adsorption type. For single dye effluent systems, adsorption results showed that the AC matrices had good performance especially at low concentrations of adsorbates. The order of adsorption for the different dyes was MO > MB > IG, while the efficiency of the matrices was PMAC > UMAC > CMAC. For binary dye effluent systems, adsorption of combinations of MB and MO (MBMO) and MO and IG (MOIG) in aqueous and aqueous Pb(NO3)2 and Cd(NO3)2.4H2O mixtures onto the AC matrices was observed. Results revealed that for MBMO system, the component that was preferentially adsorbed was dependent on the heavy metal environment and the AC sample involved. Generally, the adsorption range was 89 – 98%. For the MOIG system, the result showed similar adsorption trends irrespective of the heavy metal environment. MO was preferentially adsorbed than IG while the performance of the matrices was PMAC > UMAC > CMAC. The adsorption range was 54 – 82 %. For MBMOIG in aqueous Pb(NO3)2 and Cd(NO3)2.4H2O mixture, the components were preferentially adsorbed as follows: MO > MB > IG with an adsorption range of 73 – 97%, while the performance of the matrices was PMAC > UMAC > CMAC. With the real textile effluents, the AC matrices adsorbed components of TXT 2 and TXT 3 appreciably with average adsorption ranges of 72 – 82% and 19 – 68% respectively, while the adsorption range for TXT 1 was wide between 2 – 70% (close to 80% of the results were below 31%). The performance of the matrices was PMAC > UMAC > CMAC, just like most of the simulated effluent cases. Generally, adsorption involving multi-component adsorbate systems is dynamic and is influenced by numerous factors, like pH of AC surface, pH of adsorbate solution, size, shape and orientation of adsorbate species, concentration of adsorbate species and contact time between adsorbate and adsorbent. The resulting adsorption trend for any component is usually an inter-play of all these factors.
ADSORPTION STUDY OF Cr(VI) and Pb(II) FROM AQUEOUS SOLUTION USING ANIMAL CHARCOAL DERIVED FROM COW BONE
(2011-08) OLANIYI, IBRAHIM
A THESIS SUBMITTED TO THE POSTGRADUATE SCHOOL, AHMADU BELLO UNIVERSITY, ZARIA, NIGERIA. IN PARTIAL FULFILLMENT FOR THE AWARD OF MASTER OF SCIENCE DEGREE IN ANALYTICAL CHEMISTRY. DEPARTMENT OF CHEMISTRY AHMADU BELLO UNIVERSITY, ZARIA, NIGERIA AUGUST, 2011.

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