78 research outputs found
EFFECTIVE UTILIZATION OF BITUMINOUS ASPHALTS WASTE AS AGGREGATES IN CONCRETE
The present trend of indiscriminate dumping of waste bituminous asphalts on the highways in Nigeria calls for urgent attention. The trend all over the world now is the conservation of natural resources and reduction of waste being generated as a result of different human activities. This paper has looked at how the used bituminous asphalts material can be effectively utilized for other construction purposes. Different types of test like: slump, flow table,Ă‚Â fire resistance and compressive strength tests were carried out on the bituminous asphalt waste that was mixed with sand and cement to make concrete, and the result was compared with concrete made from granite of size 20mm, gravel of size 15mm and bush gravel of size less than 8mm. The flow table tests conducted showed that both granite and bituminous concrete mixes have low flow rate, while coarse and bush gravels have medium flow rate. The bituminous concrete has the highest cube strength of 25 N/mm2 after 28 days.Ă‚Â In conclusion, bituminous asphalts could be a very good substitute as aggregate in concrete for some marine structures that are not exposed to fire.Ă‚
EFFECTS OF PRETREATMENT ON BIOBUTANOL YIELDS FROM RICE-BRAN AND DEOILED RICE-BRAN PROCESSED WITH Clostridium saccharoperbutylacetonicum N1-4
Acid and enzymatic pre-treatment of selected lignocellulosic materials [Rice Bran (RB) and Deoiled Rice Bran (DRB)] were conducted to facilitate the release of simple sugars for fermentation process leading to biofuel production. In this study, an innovative approach involving the use of acids to breakdown the complex lingo-cellulosic structure of RB and DRB was utilised. In addition, RB and DRB samples were subjected to physical (heat treatment) and enzymatic treatments, sequentially; in order to improve the amount of simple sugar available as substrate in a microorganism assisted fermentation process. The released sugar from the various treatment regimes were subjected to fermentation process. The highest total fermentable sugar obtained from the Trichloroacetic Acid (TCA), HCl and H2SO4 treated hydrolysate were 33.07 g L-1, 27.14 g L-1 and 31.93 g L-1 for treated hydrolysates, respectively. DRB samples showed a higher total sugar yields and fermentation products than RB samples. The highest butanol yield obtained from the TCA, HCl and H2SO4 treated hydrolysate were 8.66 g L-1, 5.32 g L -1 and 7.86 g L-1, respectively, after fermentation. The Acetone-Butanol-Ethanol (ABE) yield and productivity of the TCA, HCl and H2SO4 treated DRB hydrolysates were 0.47 g/g and 0.1g L-1 h-1, 0.32g/g, and 0.07 g L-1 h-1 as well as 0.42 g/g, and 0.08 g L-1 h-1, respectively. (This is consistent with Table 1) The high ABE yield and productivity values suggest that TCA is a good novel pre-treatment agent for biomass fermentation
Principal’s Classroom Visitation and Inspection, and Teachers’ Job Performance in Akwa-Ibom State, Nigeria
This expo facto research investigated the influence of principal’s classroom visitation and inspection strategy on teachers’ job performance in Akwa-Ibom State, Nigeria. Subjects involved six hundred and sixty (660) teachers and three thousand, three hundred senior secondary school students which were randomly selected from two hundred and thirty two (232) secondary schools in Akwa-Ibom State. Data was collected with Principals’ Instructional Supervisory Strategies Questionnaire (PISSQ) and Teachers’ Job Performance Scale Questionnaire (TJPSQ). Two (2) hypotheses were tested in the study. The result of analysis utilizing one-way analysis of variance (ANOVA) indicated that principal’s classroom visitation strategy, and inspection of lesson notes strategy each significantly influenced teachers’ job performance. It is recommended that regular supervision which must include classroom visitation strategy, and inspection of lesson notes strategy be organized by government to enhance teachers’ job performance
Optimization of Process Parameters for the Carbonization of Flamboyant Pod Bark (Delonix Regia)
This study investigates the carbonization of flamboyant pod bark (FPB) for the purpose of production of effective activated carbon from the agricultural residue. Central Composite Design (CCD) under the Response Surface Methodology was employed to combine the selected process parameters [Temperature (300 - 600 0C) and Time (30 - 65 mins)] for the carbonization. FPB were collected within the fields of Ladoke Akintola University of Technology, Ogbomoso, mechanically cracked, crushed, washed with distilled water and sun-dried for seven days before eventually subjecting to carbonization, after which the resultant yields were determined and the statistical analysis was evaluated. The maximum (45.45%) and minimum (11.82%) yields were obtained at Run 1 (3000C/30 mins) and Run 11 (6000C/ 65 mins). The quadratic model equation is given as Yield = 23.27 - 3.48A - 4.38B - 2.81A2 + 0.19B2 + 0.11AB and the R2 value for the model equation is 0.9705 while the adjusted as well as predicted R2 values are 0.9459 and 0.8578, respectively. The numerical optimization by the Design Expert (6.0.8) software suggested minimum yield of 12.89%, (600 0C/ 65 mins) at desirability of 0.941. This research has indicated the suitability of using CCD for the optimization of process parameters for the carbonization of Flamboyant Pod Bark
USE OF FISH WASTE MEAL AS A REPLACEMENT FOR FISH MEAL IN THE PRACTICAL DIETS OF AFRICAN MUD CATFISH Clarias gariepinus FINGERLINGS
A feeding trial was conducted to investigate the effect of fish waste meal (FWM) on growth performance, nutrient utilization, hepatosomatic index and blood parameters of Clarias gariepinus. 150 fingerlings of C. gariepinus of average weight of 5.2±0.13g were stocked. Five (5) iso-nitrogenous diets containing 40% crude protein in which fish meal protein (67.70%) was replaced by fish waste meal protein (45.94%) at 0% (FWM0), 25% (FWM25), 50% (FWM50), 75% (FWM75) and 100% (FWM100) levels were formulated. The fingerlings were fed at 5% body weight per day for 56 days. Values for growth response and nutrient utilization parameters decreased (p<0.05) with increasing levels of FWM in diets from 50% FWM inclusion level. Feed conversion ratio showed no significant difference (p>0.05) between fish fed diets FWM0 (1.25), FWM25 (1.26) and FWM50 (1.30). Net protein utilization was highest in fish fed diet FWM0 (43.62%) but not different (p>0.05) from fish fed diets FWM25 (42.82%) and FWM50 (41.11%). Hepatosomatic index was highest significantly (p>0.05) in fish fed diet FWM100 (1.13%) and lowest in fish fed diet FWM50 (0.65%). The haematological profile was higher (P<0.05) in all parameters in fish fed diets FWM0 and FWM50. Pack cell volume (PCV) was 36.2% in fish fed diet FWM0. This was statistically similar only to 35.9% of fish fed diet FWM50. From the study, it is concluded that fish waste meal can replace as much as 50% of fish meal in the diet of African catfish, C. gariepinus.    Â
The associations of malaria parasite and ABO blood groups with aggressive periodontitis in Nigerians - a preliminary study
Objective: Aggressive Periodontitis (AgP) is a rare form of periodontitis which has been associated with aetiological factors including genetic predisposition, Aggregatibacter actinomycetemcomitans, and blood group B. It seems to have a racial predisposition being more common among blacks, particularly people of West African origin. The role of endemic factors such as malaria is yet to be investigated in AgP. The aim of this study was to explore the associations of malaria parasites and ABO blood groups with aggressive periodontitis.
Method: A preliminary case-control study on localized aggressive periodontitis patients and age and gender matched controls. Microbiological and hematological tests were performed to determine the presence of malaria parasites and ABO blood groups respectively.
Result: Eight LAgP patients and 9 age and gender-matched controls were seen. Six patients were positive for Plasmodium Falciparum malaria parasite, compared with 2 controls. This difference was statistically significant (p=0.044). The prevalence of malaria infection was not significantly associated with age (p = 0.44) or gender (p = 0.34) of the subjects.
Conclusion: This preliminary study showed a high prevalence of malaria parasites among patients with aggressive periodontitis. Malaria infection may be associated with AgP. Studies with larger sample sizes may be needed to further investigate the relationship between aggressive periodontitis and malaria infection
Global Stability of Generalized Within-host Chikungunya Virus Dynamics Models
This paper proposes two models of a general nonlinear within-host Chikungunya virus (CHIKV) dynamics. The production, incidence, proliferation and removal rates of all compartments are modeled by general nonlinear functions that satisfy a set of reasonable conditions. The second model takes into consideration two forms of infected host cells: (i) latently infected cells which do not produce the CHIKV, (ii) actively infected cells which generate the CHIKV particles. We show that all the solutions of the models are nonnegative and bounded. The global stability of the steady states of the models is proven by applying Lyapunov method and LaSalle’s invariance principle. We perform numerical simulations to complement the obtained theoretical results
Evaluation of Pharmacognostic Characteristics of the Leaf of Ageratum houstonianum Mill. Compositae
Background: It is a well-known fact that therapeutic efficacy and safety of medicinal plants depend on the quality and quantity of chemical constituents and that the misuse of medicinal plants starts with wrong identification.Objectives: The aim of this study is to establish some pharmacognostic standards for Ageratum houstonianum Mill (Compositae) which has high medicinal values, with a view to determining the proper identification and other quality control parameters of the plant.Method: The fresh leaf and powdered leaves were subjected to macroscopy and microscopy using standard procedures. In addition, some physicochemical evaluations such as moisture content, ash and soluble extractives were carried out on the powdered leaves.Results: The result shows that the leaf is simple, pinnate, diamond shaped, serrated margin, acute apex and asymetrical base. Microscopically, the leaf is amphistomatic in nature with anomocytic and anisocytic stomata at the adaxial and anomocytic and diacytic at the abaxial surface. Non-glandular uniseriate trichomes are present on both surfaces. The transverse section across the midrib shows epidermis, collenchyma, palisade cells and a few rolls of phloem around the xylem vessels. The stomata numbers and stomata indices for the upper and lower surface, respectively are1.4 and 10.2 and 2.9 and 15.6. Moisture content, total ash, acid insoluble ash, water soluble ash, sulphated ash, water soluble and alcohol soluble extractives yields 10.3%, 15.2%, 0.8%, 20.2%, 14.4% and 5.1%, respectively.Conclusion: The findings in this study are useful for establishing standards suitable for official monographs on Ageratum houstonianum proper identification and quality control.
Keywords: Pharmacognostic standards, Ageratum houstonianum, Quality contro
Selection of Mass Transfer Models for Competitive Adsorption of Antibiotics Mixture from Aqueous Solution on Delonix regia Pod Activated Carbon
The selection of suitable mass transfer models that fit the adsorption of a mixture of antibiotics in aqueous solution onto activated carbon derived from Delonix Regia Pods (DRPs) was examined in this study. The ripe DRPs were cleaned, activated with KOH and then carbonised at 350 °C. The surface chemistry of the raw and the modified DRPs were characterised using Fourier Transform Infrared (FTIR), before being subjected to batch adsorption of a mixture of Amoxicillin (AMO), Tetracycline (TETRA) and Ampicillin (AMP) under the effect of time (0-240 mins), and concentration (20-100 mg/l). The adsorption diffusion mechanisms of the process were analyzed. The spectra of the raw and modified DRP indicate the existence of hydroxyl groups alkanes, unconjugated ketone, carbonyl, and ester groups. McKay has the highest (0.9445) for the mass transfer diffusion model. This indicates that the adsorption rate of the selected antibiotics in the wastewater is regulated and monitored by the internal mass transport processes in accordance with a pore diffusion mechanism
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