In arid and semi-arid regions where water is in short supply, grey-water treatment offers the possibility of supplemental water resources for reuse in irrigation at household and farm levels. The gravest environmental challenge that Jordan faces today is water scarcity. Jordan has one of the lowest per capita levels of water resources in the world. Regions with fewer than 1000 m3 per person per year are defined as water-scarce. Water-scarcity hinders economic development, strains the environment, and drastically limits food availability . – In Jordan in 1996; per capita share of water was < 175 m3 for all uses. The country’s population increase, and the periodic massive influxes of refugees from neighboring countries, has created an increasing demand. New unconventional water resources are needed to counteract the negative water balance between supply and demand. Responding to this challenge, grey-water management in the rural and peri-urban communities of Jordan has been adopted as a solution in collaboration between the International Centre for Agricultural Research in the Dry Areas and the National Centre for Agricultural Research and Extension. The project adopted participatory approach with all stakeholders to achieve project’s objectives. Several meetings were held with community members and Community Based Organizations in the project area. Furthermore, community involvement and gender consideration are important factors to achieve sustainability in project implementation. The general goal of the project is to improve the quality of life and well-being for rural Jordanians through adopting appropriate grey-water treatment units for the purpose of crop production and income generation. A monitoring program was implemented in August 2010 in six locations. Of these locations, three used volcanic tuff material as the filtration media and the others used white gravel. The monitoring program included collection of water, soil and plant samples. The water sample analyses showed that using medium-sized volcanic tuff as a filtration media is more effective than using medium-sized gravel. There was a 73% reduction in the biological oxygen demand when using volcanic tuff and a 49% reduction when using gravel. Moreover, grey-water quality after treatment was within the permissible limits of the Jordanian standards for its use in irrigation. The results of plant leave quality and soil analysis being irrigated with grey-water showed that grey-water has no adverse effects on plant quality and soil properties. However, leaching of soil with fresh water from time to time is recommended. Furthermore, community involvement and gender consideration are important factors to achieve sustainability in project implementation.
Trustworthiness perceived by customers plays a very important role in pursuing online buying, particularly in the business-to-consumer (B2C) E-commerce (EC) purchase process. After a thorough investigation of the literature, this study reveals that privacy, security, behavioral attitudes, cognitive perception, and fulfillment/reliability are significant antecedents of perceived trustworthiness that affect the purchasing behavior of customers in B2C EC. This study reviews the literature dealing with trust in EC and develops a conceptual framework for formation of perceived trustworthiness by customers in B2C EC.
Aims: To identify and quantify prominent gamma emitting-NORMs associated with mining activities in Zamfara State, Nigeria. Study Design: Soil samples were collected from 10 different mine sites in Zamfara State, northwest-Nigeria for gamma spectroscopy analysis. Place and Duration of Study: Department of Physics, Nigerian Defence Academy Kaduna, Nigeria, between June 2012 and October 2012. Methodology: A laboratory based γ-ray spectrometry NaI(Tl) at the Centre for Energy Research and Training (CERT), Ahmadu Bello University Zaria, Nigeria was employed to carry out the analysis of the soil samples. Results: The values of activity concentration found for 40K, 238U and 232Th range from 227.10±7.54 – 590.44±10.57, 4.68±3.52 – 18.98±0.84 and 40.58±1.85 – 94.92±2.75 Bq.kg-1 respectively, while absorbed dose rate in the soil samples for 40K, 238U and 232Th range from 9.47±0.31 – 24.62±0.44, 2.16±1.62 – 8.77±0.39 and 24.51±1.12 – 57.33±1.66 nGy.h-1 respectively. The total average absorbed dose rate of the soil samples collected is 59.70 nGy.h-1 and the estimated annual effective dose for the study areas range from 52 – 106 μSv.y-1, with an average annual effective dose of 73 μSv.y-1. Conclusion: The radiation exposure level for members of the public in the study areas is within the safety limit.
Aims: Wavelet transform is the powerful mathematical tool used for image processing and noise suppression applications in different area of science and engineering. In this technique, selecting optimal threshold for de-noising is still an area of thrust for the researchers. In this paper, we have focused on the de-noising of planar nuclear medicine image using the block thresholding with different block sizes when threshold values vary for Stein, soft and hard thresholdings. Study Design: De-noising of planar nuclear medicine images via wavelet block thresholding Place and Duration of Study: University of Guilan. Methodology: We simulated planar images of hot region of Carlson phantom by GATE v. 6.1. Noisy image and reference image were produced by imaging time 10 and 40 second, from the hot region of Carlson phantom which is placed next to the simulated gamma camera. Then, we tried to de-noise noisy test image by wavelet transforms and block thresholding methods. For de-noising, we show the evolution of the de-noising peak signal to noise ratio when threshold values vary for Stein, soft and hard thresholding methods. Results: We observed that for the given noisy image, the optimal thresholds belong to the soft and Stein thresholding algorithms, respectively. Comparing the different size of blocks for the soft block thresholder by the PSNR and RMSE criterions show that the best results could be obtained by test image which is subjected to the block sizes of 3 and 4. Furthermore, Invariant soft thresholding is found to yield an overly smoothed estimate than orthogonal soft thresholding. Conclusion: Although decreasing of imaging time increases Poisson noise in the acquired nuclear medicine images, using of de-noising technique based on the wavelet transform could improve image degradation, so that the quality of de-noised test image could be compared to the reference image.
Aims: To evaluate the nutritional and sensory attributes of wheat-sesame supplemented cookies. Study Design: Multifactorial Design. Place and Duration of Study: Food Science and Technology Department, Federal University Technology, Akure, Ondo State, Nigeria between March 2011 2012. Methodology: Sesame seeds were subjected to four days germination under closely monitored conditions of temperature and relative humidity. The sprouts were derooted, oven dried at 60ºC for 6hrs, milled, sifted, packaged and stored at 4ºC. Flour was analysed for proximate, antinutrients and amino acid compositions. Germinated sesame flour was used to supplement wheat flour at 5, 10 and 15% levels to bake cookies which were assayed for proximate composition, physical attributes and sensory evaluation. Results: Germination increased protein content of sesame from 26.23% to 32.91% and reduced fat content from 52.7% to 23.22%. It also yielded positive effect on the antinutrients. Phytic acid content reduced from 31.59mg/g in raw seed to 16.20mg/g in germinated seed. Sesame seeds are rich in both essential and non-essential amino acids, processing significantly increased the values with leucine, methionine, lysine, phenylalanine, threonine and valine values higher than the recommended daily allowance. Protein, fat and ash content of wheat-sesame cookies increased with increase in sesame supplementation, 5% sesame cookies had 17.27%, 21.73% and 2.35% respectively while 15% sesame cookies had 18.80%, 25.02% and 4.21% respectively. The carbohydrate content on the other hand decreased with increase in sesame supplementation from 53.26 to 48.26%. 95:5% wheat-sesame cookies compared favourably with the control in terms of overall acceptability. Conclusion: Sensory evaluation result revealed that the cookies supplemented with 5% germinated sesame flour was well accepted and not significantly different from the control (100% wheat flour cookies) in terms of aroma, taste and overall acceptability.
Human nature often frowns on engaging or interacting with near strangers. However, on online social media networks, this is largely ignored. There is an open interaction among both known users and loosely-connected users, and as a result, the normal social barriers against interacting with strangers are lowered. This rather careless openness has resulted in the rampant increase in cybercrime and identity theft worldwide, awaiting a potential privacy disaster in the near future. Since users raise concerns about the privacy and the security of social media sites, there is the need to evaluate the perception that users have of the security on social media sites. This paper presents a technique for evaluating user perception of level of security on social networking sites using fuzzy logic. The inputs to the system were fuzzy sets representing linguistic variables for information security evaluation goals of confidentiality, integrity and availability. The IF-THEN rules were constructed using the Mamdani fuzzy reasoning technique and the defuzzification technique was done using the centroid technique. The implementation of the design was carried out using the MATLAB Fuzzy logic tool box. Using three of the popular online social networking sites namely, Facebook, Twitter and LinkedIn the results show a system that can effectively be employed to evaluate user perception of Information Security.
Investigation has been done concerning the mitigation of geomagnetic storm (a type of space weather that has the potential to cause damage across the globe with a single event) using locally generated magnetic Indices obtained from geomagnetic data from ground based Magdas magnetometers to classify the data into quiet and disturbed days thereby deducing the possible state of radio communications propagation over Nigeria. Physical mechanisms responsible for the characteristics of the ionosphere were identified. K (an index which measures the magnetic perturbations of the planetary field) and A (a linear measure of the Earth's field that provides a daily average level for geomagnetic activity) geomagnetic indices were generated locally using a simple algorithm and appropriate computer code, from MAGDAS magnetometers located at Abuja (9º 40’N, 7º 29’E), Ilorin (8º30’N, 4º33’E) and Lagos (6º27’N, 3º23’E) in Nigeria for the period 2006 – 2011 were used as the basis for the classification. Results showed that 31.85% of the days were found to be quiet while 39.36% of the days were found to be disturbed. The observed variations in the geomagnetic field responsible for the characteristics of the ionosphere over Nigeria comes probably from two principal sources, namely, transient variations - those generated by atmospheric processes such as ultraviolet radiation from the sun and partly by secular variations, which are due to internal disturbances within the Earth. Variations in the geomagnetic field are thus found to be responsible for the characteristics of the Ionosphere.
The Middle East’s largest industrial complex produces ï¬‚at steel sheets with specific properties such as low thickness, high strength and suitable formability in order to reduce the vehicle weight and fuel consumption and prevention of environmental pollution. The aim of this study is to investigate the effect of some important explanatory variables on suitable formability of manufacturing steel sheets according to primary data set. Existence or lack of existence of crack on steel sheet is considered as a binary response variable. It is determined by bending test with the angle of zero degree. Existence of multicollinearity between mentioned explanatory variables has an effect on the probability of crack existence. Because of special condition of the response variable, which is binary, the suitable regression is logistic, and correction techniques based on least squares do not work. Developments in weighted multicollinearity diagnostics are used to assess maximum likelihood logistic regression parameter estimates. Then principal component, a biased estimation method, is used in a way that it has additional scaling parameter which can accommodate a spectrum of explanatory variable standardizations. After that, by this scale parameter α, other biased estimation methods such as partial least squares, ridge and Stein are explained. They can considerably reduce the variance of the parameter estimation.
Ground granulated blast furnace slag is a finely ground, rapidly chilled aluminosilicate melt material that is separated from molten iron in the blast furnace as a by-product. Rapid cooling results in an amorphous or a glassy phase known as GGBFS or water-cooled slag (WCS). Alkaline activation of latent hydraulic WCS by 6% sodium hydroxide was studied. Nano clay is an ultrafine material that produced from firing kaolin material up to 800ºC for 2hrs with a heating rate of 5ºC/min; this can modify mechanical, microstructural and thermal properties of geopolymer products and added to the geopolymer mix in the ratio of 0 up to 7% of the dry weight. Curing was performed under 100% relative humidity and at a temperature of 38ºC. Gelenium Ace super-plasticizer was added in the ratio of 4% from the dry weight to ensure good dispersing of the used nano clay. Results showed that increasing the percentage of nano clay up to 1% results in an enhancement in the mechanical properties as compared with control mix up to 90 days, while higher ratio leads to matrix dilution and so negatively affect mechanical characteristics of the resulting products. The study of thermal properties is taken place for the different ratios by experimental and mathematical evaluation. Study shown that the thermal properties as well as thermal insulation properties improved with the increased ratio of nano clay in ratio 1-1.5%.
A study was conducted on molecular succession of bacterial community to show their response to oil spill. Crude oil contaminated soil and water samples were obtained from Agbada-Aluu, Obite, and Bonny in Rivers State, Nigeria. The PCR-DGGE method was used to generate complex molecular profile analysis of the polluted sites microbiota. The growth dynamics of the bacteria was determined by the degrading activity, bacterial population and the pH of the culture media (Bushnell-Haas broth supplemented with 2% v/v crude oil). On day 35, Bonny soil had the highest bacterial load of (17.67 ± 1.25) x104 Cfu/mL. The highest bacterial population for the mixed cultures of each sample was observed on day 7. The bacteria in Obite soil demonstrated the greatest ability to degrade crude oil with degrading activity of 246.28 ± 3.4 Units/Hr on day 7 while the lowest degrading activity of 0.9 ± 1.2 Units/Hr was obtained with Obite water and Bonny soil on days 28 and 35 respectively. The pH values (6.8 - 8.2) were slightly basic throughout the incubation period of 35 days. The PCR-DGGE showed that there were shifts in the bacterial community during the 35 days of incubation, showing that the oil affected the bacterial community. The DNA bands that showed dominancy throughout the incubation period indicates the bacteria that played a major role in the degradation of the oil which is vital for their metabolism.
Local structure and tracer diffusion mechanism in amorphous Fe and Fe80B20 solids is studied using the statistic relaxation (SR) model containing 2×105 atoms. It was found a large number of bubbles which could break-up and leads to diffusion. A bubble diffusion mechanism is proposed and the diffusion coefficient determined in term of this mechanism is in reasonable agreement with experimental data. The decrease in diffusion coefficient upon thermal annealing observed experimentally for most amorphous Fe-based alloys is interpreted as a result of reduced number of bubbles in system.
Aims: The biochemical changes affecting the quality and chemical contents (which include nutrients and phytotoxins) in leafy vegetables during storage depend on the storage conditions. It is in line with this that the work was designed to investigate the effect of freezing time on some nutrients, namely, vitamins (β-carotene and vitamin C) and mineral elements (Fe, Cu, Mg, Na and K) and plant toxins (cyanide, nitrate, soluble and total oxalates) in Hibiscus sabdariffa. Methodology: The leaves of the vegetable were stored in a deep freezer at - 4ºC for the period of four weeks and chemical analyses were conducted at weekly intervals. Results: The concentrations of cyanide, nitrate, oxalates (soluble and total), vitamin C and Mg in Hibiscus sabdariffa decreased significantly (p < 0.05) during one week of freezing and remained significantly the same throughout the storage duration, except that the soluble oxalate concentration further decreased significantly in the fourth week of freezing. β-carotene content decreased significantly (p < 0.05) in the first and second weeks of freezing, however, in the third and fourth weeks, the provitamin A concentration remained significantly unchanged. Freezing had no significant effect on Cu content in Hibiscus sabdariffa. While freezing beyond two weeks significantly (p < 0.05) decreased the Fe and K contents, the concentration of Na in Hibiscus sabdariffa was reduced significantly (p < 0.05) only in the fourth week of freezing. Conclusion: The results thus suggest that one week of freezing at - 4ºC significantly reduced the concentrations of the phytotoxins in Hibiscus sabdariffa and preserved most of the micronutrients in amount required for the normal metabolic activity of a healthy individual.
The aim of this study is to test the relevant properties of offshore sand obtained soon after dredging and to examine the effects on chloride levels of offshore sand when fresh water is drained to simulate average monthly rainfalls. The findings are valid for offshore sand that does not require washing particularly to remove organic matter and other contaminants. As per the results of sieve analysis, grading of the offshore sand is within the limits specified in BS 882:1992. The compressive strength of grade 25 concrete which is the mostly used structural concrete is also within the acceptable limits. The shell content of offshore sand for shells finer than 10 mm and coarser than 5 mm is 6.5 per cent. This is far below the 20 per cent limit specified in BS 882:1992. For grade 25 concrete produced with OPC, an allowable limit of 0.101 per cent by weight of sand was computed for chloride content in offshore sand. The chloride content of offshore sand obtained soon after dredging was 0.04%. Even a rainfall as low as 9.9 mm can reduce the chloride content (range from 0.01 to 0.05) to levels far below the allowable limit (0.101). Rainfalls as high as 581 mm could wash away chlorides almost completely (below 0.01). The study revealed that offshore sand obtained from 2 to 7 km away from the western coast, Sri Lanka soon after dredging, could be used as an alternative to river sand.
Natural dye extracts from Hibiscus sabdariffa (popularly called Zobo in Nigeria; Western part of Africa) has been used as a sensitizer for nanosized titania (TiO2) synthesized via hydrothermal route. The SEM-EDS analysis revealed the wide band gap titania (TiO2) to be almost isomorphic phase purity) with spherical particles having diameters in the range 25-40nm. The fabricated Dye-Sensitized Solar Cell (DSC) was tested and found to have photo generated current density of 0.17mAcm-2 and open-circuit voltage value of 460 mV. The fill factor and power-conversion efficiency of the fabricated DSC were determined to be 41% and 0.033% respectively. This combination of natural dye extract with nanosized titania coupled with an appropriate hole transport material promises to provide a cheap, renewable and stable solar cells, paving way for large-scale commercialization in contrast to the expensive silicon based solar cells.
Aims: The effects of pre-cooking and particle size distribution on the pasting and functional properties of trifoliate yam flours were evaluated. Study Design: 2 x 2 x 5 factorial experimental design was used for this study. Place and Duration of Study: The study was carried out in the Department of Food Science and Technology, Osun State Polytechnic, Iree, Osun State, Nigeria, between April 2011 and March 2012. Methodology: Freshly harvested trifoliate yam (white and yellow cultivars) were peeled, washed, diced, dried, milled and packaged while the precooked flour was cooked for 10 min, dried, milled and packaged. The flour was separated into different particle sizes using sieves 150, 212, 315, 425 and 500 μm. Pasting and functional properties such as bulk density, water absorption capacity, swelling power of the flour samples were evaluated. Results: Larger percentage of raw flour samples were recovered on sieve size 315 µm and 500 µm respectively while pre-cooked flour samples were retained on the sieve <150 µm and 315 µm respectively. The peak viscosities of the pre-cooked flours were lower than the raw flours and these decreased with increase in particle size. Bulk density and water absorption capacity ranged from 0.67 to 1.00 g/cm3 and 1.50-4.90 mL H2O/g respectively. Pre-cooked yellow trifoliate yam flour had higher bulk density value than the raw yellow flour at 212 µm but no significant difference (p = 0.05) exists between them. The highest water absorption capacity (4.9 mL H2O/g) was observed in the pre-cooked yellow trifoliate yam flour at 315 µm size sieve. Pre-cooked flour of white trifoliate yam had higher swelling power (9.86) at 150 µm particle size and 80ºC. The swelling power of the raw and pre-cooked flours increased with increase in temperature. Conclusion: The pre-cooked trifoliate yam flours with 150-315 μm particle sizes produced flours with higher pasting and functional properties.
The gear pair assembly remains one of the major noise and vibration sources in power transmission systems typically used in automotive, aerospace and industrial applications. The gearbox structure vibration and noise signatures are often dominated by several high-level tonal peaks that occur at the fundamental gear mesh frequency and its harmonics and other sources. In this paper, development of the concept of a method for predicting the contributions to exterior noise radiated by an original vehicle gearbox structure using measured vibration response. An idealization of the gearbox surface as a set of flat plates was used to calculate the radiation efficiency from physical properties and edge (end) constraints of each plate, and the vibration response of the gearbox structure surface was measured using accelerometers. These data were used in a simple acoustical power theory to determine 1/3-octave band sound pressure level under free field conditions for the whole and individual noise sources. Moreover, the prediction of the individual noise sources in order to pinpoint the exact problem area in the gearbox structure so that treatment or redesign can be carried out in correct way.
This study investigated the superior mechanical properties of single-walled carbon nanotubes (SWCNTs), its polymer nanocomposites using 0.5% and 1% loading of raw and purified SWCNTs in an epoxy matrix and the degree of dispersion. The extent of load transfer between the nanotubes and the matrix was studied by analysing the second order G’-band (≈2550 cm-1) of Raman Spectroscopy. The samples have been characterised from structural (Raman spectroscopy), mechanical (tensile test), physical and microstructural (SEM) point of view. Purified SWCNTs give a better reinforcing potential compared to raw SWCNTs. We found an increase in Young’s Modulus (3780 MPa-4263 MPa) and toughness (62 MPa-68.8 MPa) for the nanocomposites prepared from purified SWCNTs.
Ditch samples recovered from interval 2216 to 2716m of Nzam-1 well in the Anambra Basin, Nigeria were investigated for sedimentological, palynological age dating and paleoenvironment reconstruction. The stratigraphic successions in the well include intercalated gypsiferous shale, shale, sandy shale and shaly gypsum of varying gypsum content. Palynological zone of Milfordia spp acme zone was established. The zone is characterized by maximum development of Milfordia spp., Longapertites sp 3 and first uphole appearance of Buttinia andeevi. Other forms that mark the zone are regular occurrence of Cupanieidites reticularis, Syncolporites subtilis, Cingulisporites ornatus, Trichotomosulcites sp. 1, Periretisyncolpites sp., Auriculiidites sp., Tricolpites gigantoreticulatus, Foveotriletes margaritae, Cupanieidites reticularis, Auriculiidites sp. and Constructipollenites ineffectus. The top of the zone is marked by the final appearance of Trichotomosulcites sp. 1, Milfordia jardinei, Cupanieidites reticularis and relative increase in Longapertites marginatus, Monocolpites marginatus, stephanocolporate pollen. The interval is particularly marked by maximum development of Milfordia spp. depicting Campanian to Lowermost Maastrichtian age. The paleoenvironment of deposition is marginal marine in nature defined by higher percentage of peridinaceans such as Senegalinium spp. and Andalusiella spp. over Gonyaulacysta forms. The relative position of the sea level and climatic condition is manifested on the lithofacies, characterized by the intercalation of shale and gypsum representing different times of transgression and lowstand phases.
Aim: In this work Laser Induced Breakdown Spectroscopy (LIBS) has been used to identify the constituents of certain type of Sudanese crude oil. Study Design: This study was designed to use LIBS technique to analyze the emission spectral lines and to evaluate this technique in identifying the constituents of certain type of Sudanese crude oil. Place and Duration of Study: Department of laser system, institute of laser in Sudan university of Science and Technology – Republic of the Sudan and department of analytical chemistry, Malaga University – Spain, between June 2011 and July 2012. Methodology: Q-switched Nd: YAG laser was used to irradiate the samples and produce its plasma. The emission spectra of the plasma were collected via optical fiber and analyzed by a miniature Czerny–Turner spectrograph attached to CCD camera. Samples: Three crude oil samples collected from, Adaril Oilfield in south of Sudan were included in this work. Results: Characteristics elements in this crude oil, such as C, H, N, O, Ca, and Na were detected. The use of intensity ratios of the emission lines and bands in the samples allowed better characterization of the samples than the simple use of peak intensities. Conclusions: The analysis of crude oil samples led to efficient detection of different constituents in these samples. Using LIBS technique in the oil industry can make a real addition because of its countless benefits, (e.g. real time, precision, sensitivity, selectivity and high speed).
The latest generations of micro-scale systems are becoming more challenging to fit into designs. These chips are squeezing into smaller and smaller spaces with very little place for heat to escape. Therefore, MEMS heat exchanger has become popular in many practical applications although improvement of heat transfer characteristics is a key issue for the users as well as researchers. In the present study it is suggested that instead of using conventional working fluids, the micro sized hot structures can be cooled with an effective coolant which can be a good substitute of the conventional fluids. Ammonia has shown the highest outlet mean temperature during the study. The analysis is conducted using commercial finite element package to determine outlet mean temperature that is then used for further calculation of effectiveness, heat transfer coefficient and friction factor.
Aims: To study the sorption of Pb(II) ions from aqueous solutions by low cost adsorbent materials like kaolinite (KAO) and synthetic metakaolinite (MET) in order to validate the effects of pH, equilibrium contact time, adsorbent dose and adsorbate concentration. To investigate the sorption mechanism of Pb(II) ions on the surface of these two adsorbents through pseudo-first order, pseudo-second order, Elovich and intra-particle diffusion kinetic models. Study Design: We used a batch sorption system at 27 ºC and operated at constant pH equal to 5.5. Place and Duration of Study: Department of Chemistry, University of Dschang, Cameroon and Department of Inorganic Chemistry, University of Yaounde I, Cameroon, between July 2012 and September 2012. Methodology: For each experiment (except otherwise stated), 0.5 g of adsorbent was measured and put into a 250-mL conical flask containing 20 mL of the Pb(II) ions at the desired concentration that ranged between 10 and 120 ppm and later on agitated, filtered and analyzed by UV-Visible spectroscopy. Results: Equilibrium was attained after a contact time of 30 minutes both for KAO and MET. Maximum pHfor Pb(II) adsorption was at 5.5 and was therefore maintained at that value throughout. Maximum quantities adsorbed by each adsorbent were 2.37 mg/g for kaolinite and 1.34 mg/g for metakaolinite respectively. The most convenient model was the pseudo-second order, as per the linear regression coefficient values (r2). Equilibrium data were analyzed by Langmuir, Freundlich and Temkin adsorption models. It was inferred that the Langmuir and Temkin models (with very high r2 values) were most suited to describe the sorption of Pb(II) ions in aqueous solutions. Conclusion: These results show that KAO and MET display lower efficiency for the removal of Pb(II) ions from aqueous domestic and industrial effluents than commercial activated carbon and others from diverse origins.
Aims: The nutritional quality of a non-alcoholic beverage produced from sorghum stem sheath (Poporo) spiced with alligator pepper (Aframomum melegueta). Study Design: Multifactorial design was used for this study. Place and Duration of Study: The study was carried out in the Chemistry, Food Processing, Sensory and Microbiology Laboratories of the Department of Food Science and Technology, Federal University of Technology, Akure, Ondo State, Nigeria, between September, 2011 and July, 2012. Methodology: Dried sorghum stem sheath was cleaned by removing extraneous materials, milled and sieved. The most appropriate ratio of 1:30 (w/v) stem sheath flour to water based on preliminary test was employed for the beverage formulation. Alligator pepper was added in sequential concentrations of 0.5, 1, 1.5, 2, and 2.5% making a total of 6 samples with the control. The nutritional quality of the beverage (poporo-which is the beverage obtained from aqueous extract of dried stem sheath of Sorghum bicolor) was investigated. The samples were subjected first to pasteurization at 75ºC for 15mins. The formulated beverage samples with alligator pepper extract were analyzed to determine its nutrient profile: proximate and mineral compositions. Results: Proximate analysis of the spiced stem sheath beverage showed the moisture content to range between 87.7-88.2%, crude protein between 0.005-0.047% and crude fat from 0.009-0.140% while pH and titratable acidity were 7 and 4 for all the beverage samples respectively. The plain beverage sample had the least protein and fat contents thereby indicating the significant effect of the Aframomum melegueta spice on the beverage samples at p<0.05. High mineral contents were also recorded for the spiced beverage samples: magnesium ranged between 145-200 mg/100ml, sodium ranged between 25.00-25.20mg/100ml, potassium 23.03-26.68mg/100ml, calcium 50.00-54.54mg/100ml, iron 4.00-5.91mg/100ml, zinc 2.50-3.51mg/100ml, manganese 0.38-0.89 and copper 0.041-0.079mg/100ml. In all the samples the plain ones (control) had the least mineral contents. Conclusion: The nutrient profile increased significantly at p<0.05 with the addition of alligator pepper, the degree of enhancement was dependent on the concentration of the spice. The overall sensory evaluation revealed that the sample spiced with 0.5% extract of alligator pepper was most preferred by the panellists.
Bio-polyols are important component in polyurethane industries. The preliminary studies into the synthesis of bio-polyol products (epoxy-polyol and epoxyl-polyurethanes) from Jatropha curcas were investigated. The reactions were followed by both Infrared and nuclear magnetic resonance. Infrared analysis was performed on a Nicolet 380 Fourier-transform infrared (FTIR) spectrophotometer using NaCl cells. 1H-nuclear magnetic resonance (NMR) and 13C-NMR were obtained on a BrukerAvance 400 NMR spectrophotometer. Approximately 100mg sample was dissolved in 1 ml of deuterated chloroform. Physico-chemical characterisation of the samples for iodine value (IV), acid value (AV), saponification value (SV) and hydroxyl value (HV) were carried out by dissolving 0.25g of sample in appropriate medium and the various values determined titrimetrically. Thermal transitions of the products were studied by heating 5mg of the sample from 20ºC to 80ºC and then cooled to -50ºC on a differential scanning calorimeter (DSC). The preparation of epoxylpolyol and polyurethane from Jatropha curcas oil was smooth and efficient. Results of film and solubility properties revealed that coatings of Jatropha curcas epoxy-polyurethanes performed better with increased loading of Toluylene 2, 4-diisocyanate (TDI) up to 2wt% while their solvent resistance decreased beyond a TDI loading of 1.2wt%. DSC analysis shows the epoxy-polyurethane to be less stable compared to the epoxy-polyol.
Lightweight foamed concrete is recently acceptable for use in low strength capacity for building and civil construction purposes as a result of its peculiar features such as low thermal conductivity, low self weight and self compacting features hence its high workability. But it major demerits is its difficulty of high strength development when compared with normal concrete. The maximum strength achieved so far is less than 25MPa even at higher density of between 1500kg/m3 and 1800kg/m3. Strength development of foamed concrete depends largely on some factors which are the constituents of the base mix, the density of foam and the water cement ratio of the base mix. This paper studies the base mix parameters to produce a sustainable foamed concrete by substituting cement which is a source of carbon dioxide, a green house emission elements, with a cementitious material, fly ash within a range of 10% up to 50% and water cement ratio of 3.0 was used. Notraite PA-1 was used as foam agent and prefoamed method was adopted for the production of the foamed concrete. With a target density of 1600kg/m3, the compressive strength result of 10.5MPa reveals that a high strength sustainable foamed concrete structural panel could only be produced with 10% replacement of cement.
Aims: To investigate the feasibility and the kinetic of using cow hooves (CH) as a low-cost adsorbent for the removal of methylene blue (MB) from synthetic wastewater. Place and Duration of Study: Chemistry Laboratory, Afe Babalola University, Ado-Ekiti, Nigeria, from October 2012 to January 2013. Methodology: This study was conducted through batch process. The influence of initial pH, contact time, CH dosage and temperature on the adsorption property of CH was investigated using pH ranging from 2.0–11.0, contact time of 5-180 minutes, CH dosage of 0.15–1.0 g and temperature of 298–318 K. All experiments were carried out using 0.25 g of CH per 100 mL of MB solution except for effect of CH dosage. The equilibrium studies were carried out using MB concentration ranging from 10–100 mgL-1 at 298, 308 and 318 K and the experimental data obtained were analysed and modelled using Langmuir, Freundlich, Dubinin-Radushkevich (D-R) and Temkin isotherm models. Results: Our results indicated that a time of 90 minutes was required for equilibrium to be attained for 25 mgL-1 MB. The percentage removal of MB was found to increase with increase in pH. The isotherm data were best fitted by Temkin isotherm model. The kinetics modelling of the experimental data agreed with the pseudo-second-order model suggesting that chemisorption was the rate determining step. The values of the thermodynamic parameters (âˆ†G0, âˆ†H0 and âˆ†S0) revealed that the adsorption process was spontaneous at very low temperature, feasible and exothermic. Conclusion: Cow hoof could be a promising low-cost adsorbent for the removal of methylene blue from wastewater and this could be best achieved at high MB pH and within a period of one and half hours.
Aims: Characterization of the thermal properties of natural pumice-based lightened bricks under ASTM standards, analyzing thermal conductivity to promote thermal comfort inside buildings. Study Design: The project had four stages. The first was getting the base material (pumice). The second was developing of lightened test specimens. The third was focused on the characterization and fourth intended for the interpretation and analysis of the test results and conclusions of the project. Place and Duration of Study: Universidad Autónoma de Querétaro, from January to December, 2012. Methodology: XRD by powders with a diffractometer Bruker D-8 Advance, Cu anode at 30 KV and 30 mA, Cu Ka radiation λ = 1.54 A, from 10 to 90º on the 2θ scale at 2º /min. Mechanical tests according to ASTM C109/C109M-08, minimum compressive strength at 28 days of 7.8 N/mm2. X-Ray Fluorescence with Spectrometer SIEMENS fluorescence X-ray SRS 3000. Thermal conductivity using ASTM C177: Standard Test Method for Steady-State Heat Flux Measurements and Thermal Transmission Properties by Means of the Guarded Hot-Plate Apparatus. Results: Pumice was identified as pozzolanic material with crystalline phases of significant silica-aluminate content by X-Ray diffraction. X-Ray Fluorescence analysis confirmed the elements of the pumice, therefore this analysis confirmed the presence of Si dominant, followed by Al. Lightened bricks were developed meeting the specifications of resistance of the ASTM standards, and the properties of thermal conductivity are better than traditional sand-cement bricks; density and porosity could create a zone of thermal comfort within buildings. Apparent thermal conductivity of pumice specimens was 0.336W m-1K-1, thermal resistance 0.234W-1m2K and Expanded Uncertainty (k=2) 5%. Conclusion: Due to porosity together with worthy mechanical comportment, the natural pumice-based bricks have advantages in lighter weight-effort, tensile strength and higher thermal insulation characteristics. The analyzed pumice reduces the thermal conductivity coefficient of lightened bricks. Thermal conductivity of lightweight bricks elaborated in this work implies a superior insulation material, comparable to the highest quality insulation materials.
Aims: To examine the proximate composition and consumption pattern of commonly available plantain and cooking-banana in Ikwuano local government area of Abia state, Nigeria. Methodology: Identification of samples and data collection on consumption pattern were achieved through focused group discussion, market survey and self-administered questionnaire. Proximate nutrients were determined by standardized methods. Results: The difference in proximate nutrients, except for ash content was not significantly different (P>0.05) between ripe and unripe samples. Cooking-banana showed higher protein (5.69-6.52 vs. 4.76-5.18%), lower carbohydrate (89.37-91.30 vs. 91.96-92.70%) and higher ash (2.56-3.44 vs. 2.03-2.34%) than plantain samples, respectively. Consumption pattern indicated higher frequency of unripe plantain intake which was linked to health benefits such as diabetes mellitus management. Conclusion: This study buttresses the nutritional value of locally available plantain and cooking-banana varieties at both ripe and unripe stages. There is need for intensified nutrition education to improve the poor preference for cooking-bananas.
Aim: To evaluate the effects of fertilization on the growth performance of Cedrella odorata, Entandrophragma angolensis and Terminalia superba in nursery. Study Design: A complete randomized block design was used. Place and Duration of the Study: Screen house of the Department of Botany and Plant Physiology, from September 2011 to July 2012. Methodology: We used 10 nutrient treatments, nine of which were nutrient combinations and one, a negative control. Urea was added at 75 mg and 112.50 mg while super phosphate simple was added at 30 mg and 60 mg. Poultry manure from broilers was added at 625 g. A total of 180 uniformly growing seedlings were treated with fertilizers two weeks after transplanting. There were six replicates per treatment per species. Information on height (cm), collar diameter (mm), leaf number, leaf area (cm2) and biomass production (g) was collected fortnightly from the day of fertilizer application, for a 120 days period. Results:Cedrella odorata produced maximum seedling height (13.55 cm), leaf number (9.99), leaf area (509.20 cm2) and total biomass (18.47g), Terminalia superba showed maximum collar diameter (4.78 mm) while Entandrophragma angolensis had the least growth performances. Conclusion: Fertilization of seedlings of threatened species in nursery would be necessary, because this will ensure their survival and improve their regeneration following out planting.
The aim of this study is to measure the fuel and physiochemical properties of cashew nut oil, its biodiesel and blends with diesel fuel. The oil was extracted by soxhlet extraction method and transesterified with methanol using sodium hydroxide as catalyst. The resulting biodiesel was washed, dried and blended 20% (B20) and 10% (B10) with diesel. They were characterized following the ASTM and EN protocols and the fatty acid profile was determined by chromatography analyzer. The result obtained shows that the properties of the biodiesel are close to those of diesel and can thus be used as alternative fuel for diesel engines.
Aims: This paper addresses critical security challenges of the smart power grid due to the tight coupling between cyber and physical systems.It features approaches to inform utilities, policymakers, researchers, and consumers about practices to reduce the risks from cyber attacks. Study Design: The paper introduces key cyber-physical systems and standards of the smart grid; identifies the security threats; and shows the need for protection at various levels of the power grid.A risk-based approach has been proposed, which could be implemented to achieve the vision of a secure smart grid infrastructure. Place and Duration: The study was carried out in Ottawa, Ontario, Canada during the period of January 2012 to January 2013. Methodology: Risk in the context of the smart grid,security threats, priorities, and countermeasures have been presented anda combined framework for risk management that can be translated into continuous security improvement programs has been proposed. Conclusion: The proposed framework calls for a coordinated assessment of cyber and physical risks keeping the whole grid security goals in mind. Integrated risk management approaches are significantly needed to efficiently guide resource allocations and optimize practices at all levels of the smart grid platform to identify the risk, measure it, minimize it, and finally engineer out the risks by the use of available resources, to an acceptable and approved standards.
Aims: The present study aims to evaluate the antidiarrhoeal activity of aqueous and methanolic extracts from M. oleifera leaves by evaluating its potential as antibacterial (against pathogens like Staphylococcus aureus, Escherichia coli, Pseudomonas aeroginosa, Salmonella typhi and Vibrio cholerae), antisecretory and antipropulsive agent. Place and Duration of Study: Department of Zoology, Ranchi University, Ranchi, between January 2012-July 2012. Methodology: Plant extraction, antibacterial analysis and phytochemical analysis were done. Male albino wistar rats (150-230g) were used. The antidiarrhoeal effects were investigated by inducing diarrhoea with the help of castor oil. Results: The result showed that, the methanolic and aqueous extracts exhibited high activity against the common gastrointestinal pathogens. The minimum inhibitory concentration (MIC) of the methanolic extract was in the range 4-64 mg/mL with S. typhi being the most susceptible showing a zone of inhibition (ZOI) of 5mm at 2mg/mL. The phytochemical analysis carried out revealed the presence of carbohydrates, proteins, oils, lipids, glycosides, alkaloids, triterpenoids and steroids and absence of tannins, flavanoids and saponins. The weight and volume of intestinal content induced by castor oil were studied by enteropooling method. Standard drug atropine (3mg/kg, i.p) showed significant reductions in fecal output and frequency of droppings whereas the methanolic and aqueous extracts of Moringa oleifera at the dose of 100 mg/kg i.p significantly retarded the castor-oil induced enteropooling and intestinal transit. The gastrointestinal transit rate was expressed as the percentage of the longest distance travelled by the charcoal (marker) divided by the total length of the small intestine. Moringa oleifera extracts (both methanolic and aqueous) at the dose of 100 mg/kg significantly inhibited (P<0.001) weight and volume of intestinal content. Conclusion: The extracts of M. oleifera showed marked reduction in the number of diarrhoea stools and the reduction in the weight and volume of the intestinal contents, as well as a modest reduction in intestinal transit. The results supports the medicinal usage of the methanolic leaf extracts of Moringa oleifera and suggests that the plant extracts possess compounds with antibacterial properties that can be used as antimicrobial agents.
Aims: To investigate the levels of some physicochemical parameters in sediments collected from seven dams in Katsina State and establish possible explanations for the observed trends. Study Design: It is an analytical Study. Place and Duration of the study: The study was carried out in some selected local governments in Katsina State between September 2010 to September 2012. Methodology: The pH, conductivity and concentration of some metals in the sediments collected from seven different dams spread across Katsina State were determined. pH was determined in a sediment/water slurry using a calibrated pH meter, conductivity was determined using the saturated paste method with a calibrated conductivity meter and the concentration of some selected metals was determined using Atomic Absorption Spectrometer . Samples were collected in the rainy season, harmattan and dry seasons for two years. The average result was used in the final analysis and the result for the three seasons were statistically analysed using ANOVA. Result: It was found that Zn, Fe, and Cr had the highest concentrations in all the seasons studied with most of the values being higher than the maximum recommended values by EPA. ANOVA showed a significant difference in the concentration of all the metals in the different seasons studied, with only Fe (P=.17) showing no significant difference between the seasons. The concentration of Pb was found to be above the maximum permissible limit in harmattan . This can be due to the relatively lower pH values in harmattan and the contributions from harmattan dust deposited. Conclusion: It was concluded that apart from the numerous natural factors, human activities contribute to the variations in metal concentrations in the sediments. Regular monitoring was suggested in order to ensure the healthy growth of the inhabitants.
This study was carried out to investigate the correlation among municipal solid waste pollution, fecal coliform water pollution and water-borne diseases such as; typhoid and diarrhea in Juba city, South Sudan. Water samples were collected from the river Nile, boreholes and a well and then analyzed for the presence of fecal coliform; also physical parameters such as temperature, pH, Total Dissolved Solids (TDS) and Electrical Conductivity (EC) were tested. The results revealed that the river Nile is highly contaminated; with an average range of 15.25 – 102.6 Coliform Forming Unit/100ml (CFU/100ml). The pH and temperature were within the normal range. TDS showed very high values with range of 470 – 1230 mg/L which is far beyond the USEPA and WHO recommended 500 mg/L. The EC was not so high; ranges between 59µs - 201µs/cm which is slightly above the recommended 160 µs/cm. The CFU/100ml readings of the boreholes and the well were within the range of 0 – 26 CFU/100ml. Out of the eleven sampled boreholes, six were clean with 0 CFU/100ml which meets the USEPA and WHO recommended value but the other five and the well were contaminated. The TDS and EC were extremely high ranging between 4810 – 8230 mg/L and 1032 – 1775 µs/cm respectively. pH and temperature were within normal range. The study also found that there is strong correlation between typhoid and water contaminated with fecal coliform while the reverse is true for diarrhea. The degree of linearity (correlation) between fecal coliform (CFU/100ml) and Typhoid Fever was further confirmed by conducting a test of hypotheses (t-test statistic) at 5% significance level on the correlation coefficients determined. The study concluded that, the poor municipal solid waste management in Juba is posing high risk to the human health and the environment.
Aims: This research investigates the influences of low methoxyl pectin (LMP) and sorbitol on the morphology and secondary structure of beta-lactoglobulin (BLG). Methodology: The effects of pH and temperature on the structure of the nano-complexes containing BLG, BLG-LMP and BLG-LMP in the presence of co-solvent (sorbitol) were studied by means of a far-UV Circular Dichroism spectroscopy (CD) and the size and morphology of nano-complexes measured by particle size analyzers, Scanning Electron Microscope (SEM) and Transmission Electron Microscopy (TEM). Results: CD results at different pH levels (4, 4.5, 5.3 and 6.3) indicated that the structural changes of BLG were more pronounced relative to BLG-LMP and BLG-LMP in presence of sorbitol. However, less destruction faced the protein structure at pH 5.3 compared to pH 4.5 and 4, therefore pH 5.3 was selected. BLG-LMP in presence of sorbitol had more protective effects on the secondary structure and indicated a high thermal stability when heated up to 75ºC for 10 minutes. Particle size measurement revealed that the size of BLG aggregate was as much as 250 nm while the BLG-LMP size in presence of sorbitol nano-complex was around 100 nm. SEM and TEM observations indicated uniform and spherical nano-complexes. Conclusion: The treated bio polymer particles have suitable properties and great potential as carriers for encapsulation and delivery of bio-active materials as well as a substitution for lipid droplets.
Heavy dependence on the natural environment for agricultural production in northern Ghana adversely affects the availability of agrobiodiversity and in turn household livelihoods. Farmers have over the years developed strategies for adapting to reduction in agrobiodiversity but the extent of adoption varies among farmers. This study used the multinomial logit model to determine the factors influencing farmers’ choice of indigenous adaptation strategies in response to agrobiodiversity loss in northern Ghana. The analysis is based on a sample of 310 farmers drawn from 31 communities in northern Ghana. The factors that positively influence the choice include household head’s sex, farming experience, radio ownership, household size, borrowing credit and awareness of reduction in crop diversity. On the other hand, age, education, farm size, awareness of climate change, farm cash income and existence of market in community, negatively influence choice of strategies. Furthermore, farmer to farmer extension and off-farm income influence adoption either positively or negatively with respect to the adoption option in question. Thus, to encourage adaptation and conservation mechanisms, policies should strengthen farmer based organizations and promote education on the sustainable use of the natural environment. Government policies must also enhance access to off-farm income generating activities.
Aim: To examine the organoleptic and microbial quality of three fish species namely African red snapper(Lutjanus agennes), Mullet (Mugil cephalus) and Catfish (Chrysichthys walkeri) smoke-dried using rubber wood (Hevea brassillensis). Study Design: Factorial experiment laid in completely randomized design Place and Duration: Fisheries Department University of Benin between August and September 2011. Methodology: Fish samples were bought from Ogbe-Ijoh market in Warri Delta State. Smoking was carried out using rubber wood (Hevea brassillensis) in a traditional rectangular mud kiln (Chorkor) and stored on open benches in the laboratory at room temperature (28 ± 2ºC). Fish samples were assessed tri-weekly for moisture content and sensory attributes. Three anatomical parts of fish samples were also analyzed for bacteria load during the six weeks period of storage. Results: There was a general decline in all sensory attributes during storage. Moisture content of the fish samples varied with storage time but was not significant (P≥0.05). The highest mean bacterial counts of 3.9 x 106, 1.4 x 106 and 2.4 x 106cfu/g was recorded in the gills, muscle and skin of Chrysichthys walkeri after six weeks of storage respectively. There were significant (P≤0.05) difference in the mean bacterial count in the three anatomical parts among the fish samples during storage. The predominant bacterial species isolated from the three different anatomical parts of the three fish samples during the six (6) weeks storage period were made up of seven (7) genera of bacteria: Proteus (30.1%), Pseudomonas (26.5%), Micrococcus sp(18.1%) Bacillus (9.6%), Staphylococcus (9.6%), Escherichia coli (4.8%) and Streptococcus sp (1.2%) Conclusion: The study revealed that by the sixth week of storage all tested fish had an overall mean score of acceptability less than 6 (i.e. fair).Therefore, the fish were marginally acceptable based sensory and microbiological evaluation. This is an implication that could pose a serious health concern for consumers.
Aims: This paper describes a fast-lock, low-power, low-jitter and good duty-cycle correction capability delay locked loop with double edge synchronization which is mainly used in clock alignment process. A clock aligner’s task is to phase-align a chip internal clock with a reference clock. The main advantage of delay locked loop rather than phase locked loop is related to good jitter performance of it. Double edge synchronization method leads to more power consumption and it can increase rms and peak-to-peak jitter therefore, in this work rms jitter, peak-to-peak jitter and power consumption are implemented to understand if this statement is always true or not. So, this case became one of our aims. Study Design: Double edge synchronization delay locked loop. Place and Duration of Study: Department of Electrical Engineering (Islamic Azad University, Central Tehran Branch), between February 2012 and September 2012. Methodology: Comparing with single edge synchronization delay locked loops, double edge synchronization method has its own advantages and disadvantages. Using two phase frequency detectors, two charge pumps and two loop filters in double edge delay locked loops, increases the jitter and power consumption. In this paper, to overcome these challenges for the introduced delay locked loop circuit, proper blocks with suitable characteristic for each MOSFET were used which took a lot of time to find ones with the help of HSPICE simulator. Results: All the simulation results are based on 0.18μm CMOS technology with 1.8V supply voltage. The HSPICE simulation results show the proposed delay locked loop circuit generates clock signals ranging from 750MHz to 1GHz. The maximum power consumption of the DLL circuit at 1GHz is 3.4mW. The maximum and minimum of rms jitters are 9.12 and 0.463ps and the maximum and minimum of peak-to-peak jitters are 124.89 and 2.52ps, respectively. The locking time of proposed delay locked loop is less than 20ns within the operating frequency band. Another feature of this architecture is that it has good duty cycle correction capability (50±0.9%). It should be note that, in double edge DLL it is so important to find a balance between duty cycle (should be around 50%), jitter and power consumption. Rms jitter, peak-to-peak jitter, power consumption and also duty cycle error are calculated by HSPICE simulator. (Cosmosscope program in HSPICE simulator can be used for these measurements). Conclusion: Although designing double edge synchronization method in delay locked loops is challenging and it takes more area than single edge delay locked loops (which is mentioned as the main disadvantages of double edge delay locked loops and we all agree on this), by choosing suitable blocks it can be used without jitter performance or power consumption challenges. In other word, the results of this paper shows that all the effective and important items of introduced double edge delay locked loop (such as power consumption, rms jitter and peak-to-peak jitter) are as well as single edge delay locked loops in most articles. So when it is suitable to use double edge delay locked loop instead of single edge delay locked loop, it should be no concern about these items.
Aim: A study of energy and exergy analyses was carried out on a thermal power plant in order to investigate the interaction effects of coupling sections of the plant and overall system. Study Design: Simulation, energy and exergy analyses were used. Place and Duration of study: The plant is located at Egbin in Lagos State of Nigeria and the duration of study was between March and May 2010. Methodology: The thermal power plant was simulated using Hyprotech System Simulation (HYSYS) software and Excel spreadsheet was used for the energy and exergy analyses. The sections were grouped into four, namely: turbine-generator, condenser, regenerator and furnace-boiler sections. The energetic and exergetic efficiencies and irreversibilities at different throughputs (50, 75, 100 and 110% power outputs) were evaluated for each section and the sections were coupled into subsections one after the other until the whole sections were coupled. Results: The results showed that the furnace-boiler and the condenser sections have the least exergetic efficiencies of an average of 24.08% and 38.85%, respectively, while the energetic efficiencies of the regenerator and furnace-boiler were the least and were 67.04% and 62.74% on the average, respectively. The overall system energetic and exergetic efficiencies were at an average of 20.21% and 11.17%, respectively. Furthermore, the results showed that the closed loop topology of the thermal plant and the high irreversibilities in the furnace-boiler section made the highest contributions in determining the overall process efficiencies. The overall irreversibilities of the plant increased as the throughput increased, but the overall energetic and exergetic efficiencies were not sensitive to changes in plant throughput. Conclusion: The overall second-law efficiency (exergy efficiency) of the plant was lower than the overall energy efficiency as was expected because of proper accounting of different types of process exergies of material, heat and work in the plant.
Nutrients assay of raw and fermented African Star Apple seeds were evaluated. The proximate analyses differ (p<0.05) significantly between the raw (RSA) and processed (FSA) Chrysophyllum africanum seed in crude protein, lipid, dietary fibre and soluble carbohydrate. Protein value was 10.13±0.02%, Ash 7.25±0.01%, Crude fat 9.72±0.02% and Soluble carbohydrate 69.45±0.84% for RSA. However, the values of 5.55±0.01%, 14.49±0.76%, 4.94±0.07%, 1.19±0.01% and 51.04±0.08% were recorded for Ash, Crude protein, Crude fat, Crude fibre and Soluble carbohydrate in FSA respectively. Nevertheless, similar observations were recorded in the concentration of phyto-chemicals which decreased in all the parameters in FSA (p<0.05) compared with RSA. The FSA contained relatively higher concentration of minerals than RSA (p>0.05). Generally, there was a significant loss of nutrients in processed seed except crude protein, however, the reduction in the phyto-toxin in FSA may be an encouragement coupled with rich nutrients as a component of animal feed to replace the expensive orthodox energy feedstuff.
Aims: This study examines the consumption pattern and the existing methods of kunun production in some selected states of Central Nigeria. Study Design: Field data collection using structured questionnaires on the demography, geographical spread, production and consumption pattern of kunun. Place and Duration of Study: Federal capital territory-Abuja, Niger and Nassarawa states of Nigeria during rainy and dry season (12 month) Methodology: A total of 400 questionnaires were administered in person within the study area to traditional kunun producers, marketers and consumers. The data collected from the field were collated. Results: Of the three hundred and sixty two (362) respondents, 67% were female; while those within the age brackets of 26-30yr accounted for 26% of those producing kunun in the study area. Uneducated persons accounted for 30% of those producing kunun while primary, secondary and tertiary school graduates accounted for 20, 30% and 17% respectively. Furthermore, kunun-zaki was observed to be the most popular (67%) beverage among the other kununs (kunun-8.8%, kunun gyada-7.7%, kunun yagi-6.4% and kunun acha-3%) produced within the study area. Conclusion: Since all the kununs produced in this study area were observed to have a limited shelf-life (<24h); there is therefore the need to enhance the quality of its production using scientific processing technology.
The effect of sodium carboxymethyl cellulose (CMC) as capping agent on the optical (photo) and structural (physical) properties of zinc sulfide (ZnS) nanoparticles was studied. The capped nanoparticles were grown by the precipitation technique. The capping ratio of precursor (ZnS) to surfactant (CMC) (vol/vol) considered were 1:1 (sample S1), 1:2 (S2 sample) and 1:3 (sample S3 sample). Analyses carried out include; X-ray diffraction (XRD), scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), UV-Vis spectroscopy and photoluminescence studies. SEM analysis revealed particles as agglomerates. The obtained band gap energies of 4.13, 4.20 and 4.27 eV for samples S1, S3 and S2, respectively are blue shifted when compared to the band gap energy of bulk ZnS semiconductor indicating quantum effect. The calculated particle sizes from XRD ( 3.14, 3.73 and 15.7 nm for samples S3, S2 and S1, respectively) and effective mass approximation (3.59, 3.77 and 3.98 nm for samples S2, S3 and S1, respectively) were found to vary with the capping amount, though not monotonically. Capping ZnS with higher amount of CMC provided more stable nanoparticles, although with lower luminescence. The emission peaks of samples S3and S2 were red-shifted when compared to that of sample S1. At low CMC capping amount, the luminescence was found to be very high and blue shifted due to a greater participation of surface trap states.
Aims: To evaluate the physicochemical properties of sorghum biscuits enriched with defatted soy flour, at specified ratios. Study Design: Two - way ANOVA Place and Duration of Study: Department of Food Science and Technology, Federal University of Technology, Akure, Nigeria, from January to September, 2012. Methodology: The sorghum whole grain used was milled into flour (S) to pass a 500 µm sieve. The defatted soy flour (D) was supplied by Jof – Ideal Industry, Owo, Nigeria. Sorghum flour was blended with defatted soy flour (SD) at the following ratio – SD1 (70.00:30.00), SD2 (77.50:22.50), SD3 (85.00:15.00), SD4 (87.50:12.50), SD5 (90.00:10.00), SD6 (95.00:5.00), and SD7 (92.50:7.50) and blends were used for biscuits production. The following analysis were carried out on the biscuit samples namely - proximate composition, mineral composition, physical characteristics and colour. Results: Significant differences (P≤0.05) were observed in the proximate, energy and mineral compositions of the biscuits. The protein content ranged from 7.3 ± 0.2 to 11.2± 0.2%; crude fat ranged from 12.0± 0.2 to 18.1± 0.1%; crude fiber content ranged from 2.0 ± 0.0 to 3.8 ± 0.0% while the carbohydrate content ranged from 58.2± 0.2 to 70.6 ± 0.1%. Results obtained compare favourably with the recommended dietary intake for each nutrient. The calculated energy value ranged from 1825.8 to 2026.1 Kj/100g. The Na:K ranged from 1.0 to 1.5 while the Zn:Cu ranged from 1.2 to 3.0. The diameter of the biscuits ranged from 4.50 ± 0.14 to 5.80 ± 0.14cm; Weight ranged from 8.27 ± 0.03 to 8.90 ± 0.14g; thickness ranged from 0.62 ± 0.01 to 0.84 ± 0.06cm. Breaking strength ranged from 1.4 to 2.7N. No significant differences were observed in the L*, a* and b* values of the biscuits. Conclusion: Sorghum biscuits enriched with defatted soy flour met recommended dietary intake for each nutrient. Hence, formulated biscuit could therefore be a useful tool in reducing protein-energy malnutrition.
Aims: To develop aloe based packagings films and evaluate the antimicrobial activity, physicochemical and mechanical properties at different proportions of Aloe debrana extract, papaya leaves extract, gelatin and glycerol. Study Design: Completely randomized design (CRD) Place and Duration of Study: Addis Ababa University, between May 2010 and November 2012. Methodology: The Aloe and papaya leaves extracts were analyzed for their antimicrobial activity, transparencies and colours. The packaging films were developed by adding various concentrations of gelatine and glycerol into the solution of Aloe debrana and papaya extracts. Films were evaluated for their antimicrobial activity, physicochemical and mechanical properties. The antimicrobial activity of Aloe based films were tested on E. coli, S. typhi, S. aureus, C. albicans and F. xylarioides Results: All films exhibited inhibitory zones on the test microorganisms used in this study. A wide inhibition zone (6.52cm2) was observed on S. typhi growth whereas the least (4.20 cm2) was found on C. albicans. The developed films were soluble in water with maximum solubility (90.49%) for P1,1 and lowest (44.57%) for P0,2. The film solubility significantly increased as the concentration of glycerol augmented and decreased as the concentration of gelatine increased. Film with P0.5,2 has revealed highest tensile strength where as the lowest was obtained by film made-up from P0.5,1. Increasing gelatine concentrations significantly increases the tensile strength but glycerol has an opposite effect on the tensile strength. Film P1,2 showed the maximum elongation (180%) and the minimum elongation (89%) was obtained for P0.5,1. Conclusion: The outcomes indicated that Aloe debrana extract and papaya leaves extract with gelatin and glycerol could be good raw materials for the development of effective antimicrobial packaging films. The developed packaging films exhibited their potential for antimicrobial activity which can be used as one of the most promising packaging systems.
Aims: Development of a precipitation prediction model for Cyprus. Study Design: Precipitation data collected at 78 stations were used: data from 66 stations for model development and data from 12 stations for additional tests. Four topographic factors – altitude, slope, longitude, and latitude – were taken into account for model development. Place and Duration of Study: All variables were obtained from the observation archives of the Water Development Department of the Ministry of Agriculture, Natural Resources and Environment of Cyprus, between 1961 and 1990. Methodology: Multiple regression analysis, combined with residuals correction, was carried out to develop a precipitation prediction model. Results: The multiple regression model can explain 61.3% of the spatial variability of precipitation over the whole year, 57.5% of variability in the wet season (October–April), and 99.6% of variability in the dry season (May–September). Interpolation-based residuals correction improved the accuracy of our model (Adj_ R2=65.1%, 62.6% and 99.7%, respectively). Conclusion: This approach, as presented in this paper, could potentially be applied to Cyprus’ climate research.
Aim: To investigate the effect of defective barrier on the optimum breakdown voltage, using positive and negative needle electrodes in an air medium of 10cm gap distance. Methodology: The barriers for the tests were placed at 2.5cm from the point electrode for each test. The defective barriers were created by having holes of 6mm, 8mm, 12mm and 20mm diameter at the centre of the barrier. For each barrier position the breakdown test for positive and negative polarity for needle electrodes were carried out. Also, tests were carried out with non defective barrier and with point-plane airgap (without barrier). Result: From the test without barrier the negative point electrode offered higher breakdown voltage (1.8 times), than the positive point. When with plain barrier the positive point was optimized to 1.6 times, while the negative point was lowered. The optimum breakdown voltage decreased gradually as the hole diameter increased and at 20mm hole diameter the effect was like the plain barrier. Conclusion: From the results, optimization is only effective with positive point’s electrode and it endures even with small opening within the ionization zone. It is necessary to check this in practical situations because the specified optimum voltage of an equipment may be lowered.
Aims: To evaluate antioxidant activity and preservative effects of Thyme (Thymus Schimperi R.) on soybean oil, butter and meat food products. Study Design: Complex factorial design. Place and duration of study: Addis Ababa and Bahir Dar University, Ethiopia; between May 2010 to June 2012. Methodology: Both leave and flower part of thyme was manually harvested, dried, milled, and sieved by 420-500µm mesh size. About 10g of prepared thyme was extracted and filtered using 125 mm diameter filter paper and stored at -18â„ƒ till its antioxidant capacity and preservative effect of thyme was determined. Antioxidant activity of thyme crude extract was evaluated at 0.1% concentration as compared to 0.05% α-tocopherol and none-thyme extract treated soybean oil and butter samples using Rancimat and Schaal Oven test methods. The preservative effect of thyme was also studied by performing chemical and microbiological analysis on 0.1 and 0.2% thyme extract supplemented soybean oil, butter and meat for three consecutive weeks. Results: Thyme extract increases the induction time of soybean oil from 1.92 to 3.25 hrs and five to six days as determined by Rancimat and Schaal Oven test; respectively. It also improves the induction time of butter to 5.28 hrs from 3.78hrs of control butter sample. Highest microbial load was obtained in controlled samples of butter and meat. Samples containing 0.2% thyme extract have lower value for all total viable microbes, mold & yeast and enterobacteriaceae counts of meat and butter. Conclusion: Thyme extract significantly (P<0.05) improved both the microbial and oxidative stability of food samples. Thus, Thymus schimperi is a potential herb having antioxidant activity and preservative effect as it was evaluated on soybean oil, butter and meat. Thyme, which is abundantly available in Ethiopia, can be used as a source of antioxidant for production of shelf-stable food products via advance research and development activities.
Dried fruits have limited food use, this study explored the food utilization potential of dehydrated pineapple slices. The influence of 50 °Brix sugar and 47:3 % w/w sugar/salt solutions on the quality of jam produced were investigated. Pineapple slices were osmotically dehydrated (4 hr), oven dried (60 â„ƒ 27 hr), and rehydrated at 90 â„ƒ for 15 min and at room temperature (RT) for 6 hr. Jams were made from dried pineapple slices (with or without osmotic dehydration), fresh pineapple and compared with commercial pineapple jam. Chemical and sensory properties of the jam were conducted. Osmotic dehydration contributed to the titratable acidity values, rehydration temperature had no significant (P<0.05) effect on total soluble solid of the samples dehydrated in sugar/salt solution, also the moisture content increased as the rehydration temperature was increased. Osmotic dehydration of fruits prior to drying had effect on the retention of the vitamin C and protected reducing sugar from being lost. Panelist revealed that jam samples produced from pineapple dehydrated in sugar solution and rehydrated at room temperature were most preferred. The results suggest that surplus fruits can be preserved by osmotic dehydration followed by oven drying for later use in jam production.
Binary operations are introduced for triples satisfying zero curvature equations and quadruples satisfying generalized zero curvature equations, and it is shown that such operations define Lie algebra structures on the corresponding spaces of triples and quadruples.
Aims: Aim: Experiments were conducted to evaluate the performance of a LHR diesel engine with air gap insulated piston, air gap insulated liner and ceramic coated cylinder head [ceramic coating of thickness 500 microns was done on inside portion of cylinder head] with different operating conditions [normal temperature and pre-heated temperature] of waste fried vegetable oil based biodiesel with varied injection pressure and injection timing and compared the performance with pure diesel operation on CE. Study Design: Performance parameters of BTE, BSEC, EGT, VE, CL, Sound intensity were determined at various values of BMEP of the engine. Methodology: Exhaust emissions of smoke and NOx were recorded at different values of BMEP of the engine. Combustion characteristics at peak load operation of the engine were measured with TDC encoder, pressure transducer, console and special pressure-crank angle software package. Results: Conventional engine (CE) showed compatible performance, while LHR engine showed improved performance with waste fried vegetable oil based biodiesel at recommended injection timing and pressure. The performance of both versions of the engine was improved with advanced injection timings and at higher injection pressure when compared with CE with pure diesel operation. The optimum injection timing was 33ºbTDC with CE while it was 32ºbTDC for LHR engine with biodiesel operation. Relatively, peak brake thermal efficiency increased by 18%, brake specific energy consumption decreased by 6%, exhaust gas temperature decreased by 75ºC, volumetric efficiency decreased by 5%, coolant load decreased by 30%, sound intensity decreased by 35%, smoke levels decreased by 27% and oxides of nitrogen levels increased by 41% with biodiesel operation on LHR engine at its optimum injection timing, when compared with pure diesel operation on CE at manufacturer’s recommended injection timing.
Aim: The preservative effect of waxes (paraffin and ester) in addition to buffers (pH 9 and 10) and aqueous extracts (P. biglobosa pod, G. senegalensis and B. aeyptiaca leaves) were studied on fruits and vegetables. Methodology: The preservative effects of the waxes was determined by treating fresh ripe tomatoes, peppers and oranges with buffer (pH 9, 10) for 2 minutes and wax for 3 minutes using the dipping method and for extracts, washing daily with 5mg/ml or 10mg/ml for 3 minutes. Controls were untreated and unwaxed. Number of days taken for fruits and fruit vegetables to deteriorate was recorded and compared. Results: Results showed waxing was highly effective on pepper (30 days), moderately effective on orange (26 days) and fairly effective on tomato (15 days). Among the waxes, paraffin was more effective (9 – 30 days) in increasing shelf life than ester (9 – 14 days) and the control (6-8 days). P. biglobosa extract application proved more effective (17 - 26 days) than Guera senegalensis (13 – 14 days), Balanites aegyptiaca (8 - 13 days) and the control (9-11 days) in extending the shelf life of the test fruits and vegetables. Statistically, significant differences (P > 0.05) exist between shelf life of tomatoes, oranges and peppers used as control and those subjected to treatments. Comparison of the preservative activity indicated paraffin wax > P. biglobosa > G. senegalensis > B. aegyptiaca > ester wax. Conclusion: Application of waxes and plant aqueous extracts to preserve seasonally available fruits and vegetables could provide a cheap and economically viable method of preservation that could be adopted by farmers in Nigeria, where storage facilities for such products are insufficient.
In this competitive world, administrative and production oriented organizations require people with specialized skills in various fields. In this context it is important to develop recruitment models which help organization to determine the optimum time/cost for recruitment in manpower planning. Generally problems related to recruitment are solved by applying stochastic and optimization techniques. In this paper, we consider recruitment under fuzzy environment and solution is obtained using cluster analysis and fuzzy techniques.
Aims: It is the intention of the authors to through this paper; evaluate the current situations in Nigeria by highlighting the recent reforms in the solid minerals sector and how these reforms can help sustain viable mineral exploration and mining activities. This study aim at informing the investor in the solid mineral sector how these reforms promote good investment climate and ensure good Return on Investment. Methodology: We included results from international literature related to mining and investment (including World Bank and Fraser Institute publications), recent studies specific to the Nigerian context (including studies and activities carried out by the Nigerian Geological Survey Agency), interview data with key participants who represent global mining experts and, the author’s personal experience in exploration activities specific to Nigeria. Results and Conclusion: Mineral resources occurrence in Nigeria or any country transcends political boundaries. But the industry involved in its exploration and exploitation, thrives well in an enabling environment like; favourable economic, legal, political and technological regimes. In order to compete with other countries/ mining destinations advanced in the exploration and mining of solid minerals and to woo investors, the Nigerian/ Oyo State Government of have taken some steps so as to help create an enabling environment for the mining/mineral industry. (These include: Baseline Geochemical Mapping of the country covering about 90% of Oyo Sate; Airborne Geophysical Survey of Nigeria which covers 100% of Oyo State; Systematic Geological mapping of 1:50,000 of the major topographic sheets of Nigeria including Shaki, Igboho, Ikomu, Lechilaku, Oyo, Igangan, Ibadan, Ogbomosho and Igbeti ( NW,SW,NE and SE Sheets) all in Oyo State; Gold Exploration in Oyo State; Dimension stone project in SW Nigeria, including Oyo State; Nomination of structural zones for Gold vein mineralization, Kimberlitic fields and per-alkaline intrusive using Aerial Radiometric and Magnetic Data covering Oyo State. Evaluation of the recent mining policies of Nigeria from the global mining perspective and the expectations of the international mining audience, show that, Nigeria is in the process of being transformed into an irresistible mining destination for local and foreign investors.
Background: Nosocomial infections have become a major challenge in health care delivery institutions, as they affect the quality of health care delivered. The medical imaging department is central within the hospital to the diagnosis of illness and disease; hence the need to investigate the role of the imaging department in the spread of nosocomial infection within the health care institutions. Aim: This study was carried out to investigate whether x – ray equipment and accessories harbour nosocomial pathogens, and their potential role in causing nosocomial infections within healthcare delivery institutions in government and private hospitals within the study area. Study Design: A non-experimental, prospective study design was used. Place and Duration of Study: This study was carried out in some selected medical imaging departments in Anambra state from March to July 2012.
Method: Wet Sterile swab sticks were used to swab the surfaces of selected x-ray equipment and accessories, at the close of work. The swab samples were then taken to the microbiology laboratory for culturing and identification. MacConkey and Blood agar media (inhibitor) were used to prepare the culture media. The prepared media were put in petri dishes and swab samples were inoculated onto the culture plates. Culture plates were then incubated for 24 hours, at a temperature of 37ºc. At the end of the incubation period, the culture plates were viewed macroscopically under a bright light, to identify the bacteria; according to their colonial characteristics. Data were analysed using frequency and percentage. Results: Bacteria were isolated in 182 samples (86%), out of the 200 samples collected. Bacteria isolated were; Staphylococcus aureus (140), Pseudomonas aeruginosa (88), Proteus spp (28), Streptococcus (52), and Coliform spp (80) Staphylococcus aureus was the bacterium isolated most often (140 times), while Proteus spp. was isolated the least number of times (28 times). But the largest number of sample was recorded on cassettes (60 times), for both government and private institutions. Bacterial isolates had a higher prevalence in government institutions (96), except Coliform spp. which had a higher prevalence in private institutions. Conclusion: This study has established the bacteria contamination of X – ray equipment and accessories used in the medical imaging departments of health care delivery institutions. Hence, these equipment and accessories have a potential to cause nosocomial infections in patients and health care workers.
Aims: Chemiluminescence determination of ethylene glycol. Place and Duration of Study: Samples: Antifreeze samples purchased from markets (Erbil, Kurdistan region, Iraq), between April 2011 and August 2011. Methodology: A novel chemiluminescence (CL) reaction was based on the oxidizing reaction of luminol by in situ generated bromine in alkaline medium. The CL intensity could be inhibited in the presence of ethylene glycol (EG). A new CL method was developed for the determination of EG by coupling with flow injection analysis (FIA) with merging zone principle. Because of the toxic and corrosive nature, difficult handling and high reactivity, which results in highly exothermic and non-selective reactions of bromine, the bromine (Br2) will be generated in situ via the oxidation of hydrobromic acid (HBr) with hydrogen peroxide (H2O2). Results: The relative CL intensity was proportional to the concentration of EG in the range of 35–440 µg/ml with the detection limit of 32 µg/ml and correlation coefficient of 0.9979. The relative standard deviation was 0.82% for 200 µg/ml EG. Conclusion: The proposed method was successfully applied to the indirect determination of EG at the level of µg/ml in antifreeze samples. The error varied from –4.88% to 2.76%. A possible mechanism of the CL reaction was discussed by relating to the CL kinetic characteristics.
Aims: This article aims at simulating the forces and dynamic load that the peduncle of a robotic fish using vulcanized natural rubber for its joint and plywood for its tail fin will experience. Methodology: Using standard strength of material equations and constitutive equation that fits the selected natural rubber, the loads that will be encountered in a water with density 990kg/m3 were calculated. The result was then used in ANSYS multiphysics environment to setup the simulation of the response of the peduncle to the calculated loads. Autodesk Inventor 7 was used for the geometrical drawings and calculations such as area and centroid of the non standard shape. Furthermore, the Payne effect for the rubber joint was found experimentally as its result will guide in the threshold of tail oscillation frequency allowed. Results: von Mises stress within the components of the peduncle due to the drag load was found to be 0.03kN/m2 to 4.64kN/m2 for the rubber and 0.03kN/m2 to 41.48kN/m2 for the plywood fin. Stress experienced by the peduncle under its own weight shows that for the rubber component, the maximum von Mises stress experienced by the rubber is 4.9kN/m2 and for the plywood material, it is 1.087kN/m2. Test for warping/ bending of the peduncle shows a straight isoline pattern. Tensile stress within the epoxy bonded joints shows a uniform bond pattern. The dynamic torque experienced by the peduncle increases with frequency of oscillation and even more rapidly as the angle of swing increases though at a fixed ratio to each other. Frequency induced softening (Payne effect) shows that the rubber will become soft as the frequency reaches 25Hz. Conclusion: The use of plywood material for the fin and vulcanized natural rubber for the joint and using epoxy glue for the designed peduncle of the robotic fish will be capable of withstanding the stresses that will be developed in real life scenario.
Aims: To determine the proximate and mineral composition of juices of some Nigerian fruits. Study Design: Completely randomized design (CRD) was used in the experiment. The data obtained were subjected to analysis of variance (ANOVA) to determine if significant differences existed between the means of the different fruits. Where differences existed, Duncan’s Multiple Range Test (DMRT) was used to compare the difference between the means. The experiment was conducted at the Department of Chemistry, Ignatius Ajuru University of Education Port Harcourt between January to March 2012. Methodology:Psidium guajava, Musa paradisiaca, Carica papaya L., Citrus sinensis, Malus domestica, Citrus lanatus, Annona muricata, Irvingia gabonensis, and Ananus comosus were purchased in Rumuolumeni market, Port Harcourt in Rivers State of Nigeria and were analysed. The determinations of the proximate and mineral composition of the juice samples of the fruits were determined with the use of Atomic Absorption Spectrophotometer (AAS) (Perkin-Elmer Model 372) instrument according to Association of Analytical Chemist (AOAC), (1990) procedures. Results: The least crude fibre was found in Malus domestica (0.00%) and the highest in Citrus sinensis 3.55 ± 0.02%); protein values, of 1.28 ± 0.10%, 1.25 ± 0.21%, 1.05 ± 0.01% were obtained for Psidium guajava, Musa paradisiaca and Citrus lanatus respectively. Low lipid contents were obtained from analysed samples. High carbohydrate values of 18.46 ± 2.80%, 18.26 ± 2.51% and 16.05 ± 1.32% were obtained for Citrus sinensis, Carica papaya L. and Annona muricata respectively. The value of dry matter was highest in Citrus sinensis (25.00 ± 3.13%) and least in Citrus lanatus (10.40 ± 0.63%). High moisture values of 89.60 ± 3.52%, 87.30 ± 4.32% and 85.07 ± 2.50% were obtained in Citrus lanatus, Carica papaya L. and Ananus comosusrespectively. Generally the ash content of the fruits was found to be low. The mineral analyses showed that the potassium content of these samples were relatively high with Musa paradisiaca having the highest value of 380.05±6.85 mg/g compared with Annona muricata 26.15 ± 4.21 mg/g with the least value. Concentrations of iron, magnesium, zinc, and calcium were highest in Ananus comosus (3.28 ± 0.20 mg/g), Musa paradisiaca (45.71 ± 4.55 mg/g), Irvingia gabonensis (1.26±0.30 mg/g) and Carica papaya L. (84.90 ± 3.57 mg/g) respectively Conclusion: The results showed that these fruits have safe and adequate dietary nutrients if consumed in the right proportion.
The study aimed at measuring the profitability of swine farmers, as well as determining the influence of the farmers’ socio-economic characteristics on their output. It was conducted in Kaduna State, Nigeria using structured questionnaire administered to 120 swine farmers. The respondents were randomly selected from Jema’a and Zangon Kataf Local Government Areas and information relating to objectives of the study was obtained. Descriptive statistics, multiple regression model, t-test of significance and net farm income were used to analyse the data. The study revealed that swine production in the study area predominantly carried out by women of active age. Profitability ratios showed that swine production was profitable with a return per naira invested (38kobo), profit margin (27%), gross ratio (73%) and a net farm income (N 3,178.55 per pig). The cost of feed, purchase of piglets and family labour constitutes the major variable cost items (81.96%), with an average sale of N11, 624.77 and average total cost of N8, 446.22The result also showed that swine production was influenced by socio economic characteristics: production experience, household size, herd size, age and level of education were significant (P=.05 and .01). Z-test also revealed a significant difference (P=.01) between farmers’ costs and returns. High cost of piglets, high cost of feeds, outbreak of diseases and high piglet mortality rate were the major constraints faced by farmers. The study recommends that producers should be assisted with financial capital to be able to effectively rear pigs and also expand the scale of production.
In many situations, instead of a complete sample, data are available only in grouped form. In this situation the values of individual observations are not known, but the number of observations that fall in each group is only known. Here the model under consideration is the exponentiated Fréchet distribution. The aim of this paper is finding the MLE's for the parameters of the exponentiated Fréchet distribution based on grouped data. The asymptotic variance-covariance matrix has been derived and computed numerically. Optimal group limits in the case unequi-spaced groupings so as to have a maximum asymptotic relative efficiency are worked out.
Evaluation of Eyram field reservoir has been undertaken in this work for determination and distribution of petrophysical properties, fluid type and hydrocarbon contact within B-Horizon using log data. Eyram field is located in onshore area of the Niger Delta and it essentially contains oil and gas producing reservoirs. The field consists of the reservoirs of the Agbada Formation, Niger Delta, a succession of alternating deltaic sands and shale layers. Well log data from 21 wells of the field were studied to characterize the porosity, permeability and water saturation of the B-reservoir. The logs were environmentally corrected and normalized, volume of shale, permeability and porosities were calculated, water saturation were determined by Archie’s equation and dual water model, and net pay was calculated. Within the B-reservoir of the Eyram field, the average well has 103.94ft of net sandstone, having average porosity of 26%. Shale volume ranges from 2% to 31% with an average of 21%.The average permeability is 399mD, average water saturation is 48% while average hydrocarbon saturation is 52%. Porosity and permeability in the field is high on the average due to very good to excellent sand quality.
Aim: The aim of this study was to report the seasonal variation in phenological pattern as a function of rain fall and temperature. Place and Duration of Study: This study was conducted in Nikyal valley located at altitudinal range of 1500-1900 m within the longitude 74o 04′ to 10′ east and latitude 33o 26′ to 29′ north during July 2012 to June 2013. Methodology: A phenological record of plant species was organized on the source of field trips and visits conducted every month. The plants were then classified in to different phenological stages. Results: There were 110 plant species of 51 families consisting of 5 trees, 29 shrubs, 55 herbs, 18 grasses and 3 ferns harbouring in Nikyal valley. The investigated area had only one flowering season. Majority of herbaceous, shrubby trees species flowered from April to May and the flowering reached to the peak during May and June. Conclusion: The variation in phenological patterns controlled by the amount and timing of precipitation inputs during the growing season.
Soil contaminated with heavy metals can result to very serious environmental hazard. As a result of this problem, this research was carried out to investigate the concentration of heavy metals (Fe, Zn, Pb, Cu and Cr) in and around Uwelu scrap car dumpsite in Benin City, southern Nigeria. In carrying out this research, a total of 36 soil samples were taken for laboratory analysis. The soil samples were collected at various depths at the dumpsite, and at various horizontal distances from the dumpsite including human settlements close to the dumpsite, in order to ascertain the levels of toxic heavy metal concentration on human living habitat around the dumpsite. The heavy metals in the waste soils samples were sequentially extracted and measured using atomic absorption spectrometry (AAS). The results show that Fe had the highest concentration of 515mg/kg, followed by Zn, 236.8mg/kg, Cu, 78.61mg/kg and Cr, 0.94mg/kg at the dumpsite surface, where all the metals recorded their highest concentration. The level of Fe and Pb were above the Federal Environmental Protection Agency (FEPA) minimum acceptable limit. Besides, the concentrations of these heavy metals decreased with increased vertical depth at the dumpsite and with increased horizontal distance from the dumpsite. Similar trends were observed for the various soil pH.
Condensate-to-gas ratio (CGR) plays a significant role in sales potential assessment of both gas and liquid, design of the required surface processing facilities, reservoir characterization and modeling in gas-condensate reservoirs. This work aim at the use of regression method to develop Condensate gas ratio (CGR) correlations using dataset obtained from Western Niger Delta region. The formation was divided into three distinct geologic zones: Transitional Paralic, Paralic and Marine Paralic zones. The basic parameters used for the correlation development are: reservoir depth (ft), reservoir pressure (psia); reservoir temperature (oF) all at (Gas – Oil – Contact (GOC) / Gas – Down – To (GDT) / Gas – Water – Contact (GWC)) and these parameters are data easily obtained from the field. A statistical assessments show that the models predicted CGR with a percent mean absolute error of 19.5640, correlation coefficient of 0.9539 and a rank of 18.15. These results show that the models are suitable for these fields.
Aims: The aims of this study were to determine the levels of lead (Pb), Cadmium (Cd), Copper (Cu), Chromium (Cr) and Zinc (Zn) in two economically important Nigerian fish species, tongue sole, Cynoglossus brownii and Croaker, Pseudotolithus typus from Makoko and Koko in Lagos and Delta states respectively; compare the levels of these metals with recommended international tolerable levels thereby creating awareness on potential health risks of human consumption of these fish species. Study Design: The study locations were purposively selected, being coastal locations where major industries and crude oil exploration facilities are located; and with a high probability of discharging effluents with high levels of heavy metals. Twelve samples each of both fish species were purchased from landing sites in Makoko (Lagos State) and Koko (Delta State) respectively and transported in ice boxes to the laboratories for subsequent analyses. Place and Duration of Study: Department of Environmental Management and Toxicology, Federal University of Agriculture, Abeokuta (FUNAAB) between May, 2010 and April, 2011. Methodology: Twelve samples each of tongue sole and croaker were collected bi-monthly from each sampling location in May, July and September, 2010 (Wet season) and November (2010) and January and March, 2011 (Dry season). Six samples each were analyzed for heavy metal contents using Atomic Absorption Spectrophotometry (AAS) after wet digestion of dried, milled samples of the fish muscles with 1:1 HNO3: H2O2. Results: Metal contents (µg/g, dry weight) for tongue sole in Lagos and Delta states during the wet season (April – October) were: Pb (0.330 and 0.149), Cd (0.097 and 0.063), Cu (0.869 and 0.434), Cr (1.184 and 0.826), Zn (7.612 and 7.890); for croaker: Pb (0.163 and 0.045), Cd (0.115 and 0.029), Cu (0.990 and 0.694), Cr (1.008 and 1.038) and Zn (6.756 and 6.168). For the dry season (November – March) metal contents obtained were: Pb (0.534 and 0.527), Cd (0.373 and 0.410), Cu (0.437 and 0.556), Cr (0.834 and 0.983), Zn (6.764 and 9.343) for sole; and Pb (0.210 and 0.213), Cd (0.264 and 0.307), Cu (0.442 and 0.483), Cr (0.577 and 0.597) and Zn (4.783 and 5.924) for croaker. Significant (P = 0.05) variations were observed in metal content between sole and croaker and also between dry and wet seasons notably for Cd, Cr and Cu. Generally, metal concentrations were higher in sole than croaker; and Cadmium content was significantly (P = 0.05) higher in fish samples during wet season, while Chromium and Copper were significantly (P = 0.05) higher during the dry season. Cd and Cr levels in the test species were found to exceed recommended international tolerable levels. Conclusion: Heavy metal contents varied among the fish species evaluated and also between seasons. During the dry season, chromium and copper contents of fish were significantly higher, while Cadmium content of fish was significantly higher during the wet season. Cadmium and Chromium contents exceeded international tolerable limits, thus continued consumption of these fish species could expose consumers to serious health risks arising from metal toxicity. A programme of continuous monitoring and control of the physical and chemical characteristics of the components and food products of Nigeria’s coastal zone is recommended as a management tool for this important ecological zone.
The study aimed at analyzing the technical efficiency of acha production using structured questionnaire administered to 200 randomly selected acha farmers in Kaduna State. The data were subject to analysis using the stochastic frontier production function and the gross margin analysis in order to achieve the set objectives. The scale coefficient (1.16) indicates that the farmers are operating at increasing returns to scale, that is, stage one of the production phase. The technical efficiency score of each respondent revealed that the most efficient farmer operated at 96% efficiency, the least efficient farmer was found to operate at 53% efficiency level, while the most frequently occurring efficiency score was 81%, indicating that farmers still have room to increase the efficiency in their farming activities as about 19% efficiency gap from the optimum (100%) is yet to be attained by all farmers. The technical inefficiency model revealed that the farmers’ selected socio economic characteristics (production experience, contact with extension agent, household size, level of education and off farm income) and transaction cost variables (harvesting cost, processing cost, storage cost, transportation cost, farm distance) contributed immensely to the technical efficiency of acha farmers, as the variable were significant (P=.01). Acha production is profitable in the study area. Important constraints encountered by acha farmers include high cost of labour, inadequate capital and high cost of inputs. The study suggests increase in the use of inputs by farmers as well as investing in research and extension activities by the government so that farmers can make better decisions regarding input and cost allocation in farming.
Aims: The effect of varying moisture content on the mechanical properties of Dika (Irvingia gabonensis) fruits and nuts was carried out. Some of the mechanical properties investigated were deformation at peak, energy at peak, deformation at break, energy to break, force at peak, force at break and Young’s modulus. Study Design: Dika nut and dika fruit samples were each separated into six different portions named F, E, D, C, B and A, analysis carried out were in duplicate Place and Duration of Study: Federal University of Technology, Akure, Nigeria, where preliminary analyses were carried out and Federal Institute of Industrial research, Oshodi (FIIRO), Lagos Nigeria where the mechanical properties were analyzed using Testrometric AX type DBBMTCL – 2500Kg Equipment. The research was carried out between March and September, 2012. Methodology: Each sample was oven dried until required moisture content (5%, 8%, 11%, 14%, 17% and 20% d.b. respectively) were attained the samples were separated into six portions and oven dried until required moisture content (5%, 8%, 11%, 14%, 17% and 20% d.b. respectively were attained). Each sample of the treated dika nuts and fruits was placed between the compression plates of the testing equipment. The samples were compressed at a constant deformation rate of 40.00mm min-1. The procedure was repeated for the all the samples. The data logger attached to the machine recorded the parameters. Results: There was no significant (p=0.05) difference on the effect of moisture (8 % to 20 % d.b) on the force at peak of dika fruit except at moisture content (5% d.b). The effect of moisture on deformation at peak, energy at peak, deformation at break, energy to break, force at break and Young’s modulus were significantly (p = 0.05) different at 8% and 5% b.d while there was no significant (p = 0.05) difference at moisture content 11% to 20%. The effect of moisture on the dika nut mechanical properties also showed similar behavior as that of dika fruit. Lower moisture (5% and 8% d.b.) significantly (p=0.05) affected the mechanical properties while higher moisture (11% to 20 % d.b) did not significantly affect the properties Conclusion: As the moisture content reduces, the better the mechanical properties of dika nut and fruit, hence, improvement in their postharvest handlings.
Recently, E-learning tools have proven to be potential platforms for management and progress in the education sector. The usage of mobile learning (M-learning) tools in the field of Learning Management Systems (LMS) is an interesting area of research that worth to be investigated. M-learning can offer higher learning and teaching autonomy for the education sectors and individual learners alike. M-learning can support ubiquitous learning hence portraying it as a potential candidate for future distance education. Various research works have been performed in M-learning related to its design needs and application development challenges. This paper highlights the trends of traditional learning systems and establishes a relation between modern mobile technologies and current learning paradigm. It discusses the major benefits that can reflect on the education sector, whereas the major challenges are also put into consideration while adopting M-learning services. The potential economic impact of M-learning adoption is also considered while taking into account the students, staffs and the concerned organizations. Three case studies were used to achieve and complement the research objectives in exploring major challenges and benefits of M-learning adoption.
Human gait is a non-linear complex process requiring appropriate mathematical measuring tools. Entropy is a measure that quantifies regularity in time series: the more predictable a series is the lower the entropy value. The mathematical methods used to estimate entropy have evolved over time. At present, three algorithms are the most used to study human gait complexity: the approximate entropy (ApEn), the sample entropy (SampEn), and the multi-scale entropy (MSE). Most studies on human gait complexity have been conducted on elderly subjects or subjects with specific disorders affecting gait patterns and they used ApEn; but, because of a set of conceptual errors, the ApEn is not the most appropriate algorithm for the analysis of biological signals. Very few studies use SampEn or MSE to analyze human gait variability, but they agree that these algorithms might contribute new perspectives in the analysis of human gait and that MSE seems to be the most sensitive algorithm to changes in gait in healthy subjects.
Aims: This review was undertaken to examine the potential use of taro (Colocasia esculenta) and its by-products as an alternative energy source for feeding animals. Previous Study: Previous studies indicated that raw sundried taro meal contained about 87.90-90.57 percent dry matter, about 4.93-7.07 crude protein, 2.70-3.90 percent crude fibre, 2956 – 2966 (Kcal/kg) metabolisable energy. Taro is not a common food for man, and its use in animal nutrition is however limited by the presence of anti-nutritional factors such as oxalates, saponin, phytate, and tannins. Conclusion: Taro (Colocasia esculenta) is a less well known source of energy which is not in great demand for human food. The use of taro (Colocasia esculenta) in animal nutrition should be maximally exploited as a way of reducing the competition between man and animals for maize utilization, since the quantity of grains produced in tropical Africa is not sufficient to feed the increasing human population. Heat treatment and protein supplementation are however recommended for optimal use of Colocasia esculenta in animal nutrition.