Characterization of rapidly solidified commercial grey cast iron in drop-tube

This study presents containerless solidification of BS 1452 grade 250 commercial grey cast iron using 6.5m drop-tube apparatus. It gives a comparative summary of microstructural changes that occur between the rapidly cooled droplet particles as against its conventional slowly cooled control as-cast sample. The bulk as-received sample was melted and rapidly cooled during free fall in high vacuum containerless equipment. These rapidly solidified samples were collected and sieved into size ranges from >850 μm to <53 μm diameter, corresponding to estimated cooling rate of 500 K s-1 to 75,000 K s-1 with each sieve fraction being prepared for metallographic characterization. The analytical methods used include; light optical microscope and scanning electron microscopy, x-ray diffraction and differential thermal analyses. The result of this investigation reveals that the microstructure of the as-cast sample shows flake graphite randomly dispersed in ferrite matrix which is typical of slowly cooled grey cast iron. In contrast, flake graphite was absent in virtually all drop-tube samples even those with modest cooling rate. The evolved microstructure clearly shows the effect of cooling rate on the transformation from the conventional to rapidly solidified droplet particles in terms of microsegregation

Coverage of organic agricultural news in nigerian newspapers: Implications for the promotion of ecological organic agriculture (EOA) and food risk reduction

Organic agriculture is the alternative practice to conventional agriculture. It provides a better, safe and healthy alternative farming systems.However, the accurate knowledge of organic agriculture as a profitable alternative practice to conventional agriculture is still inadequate. Therefore, there is need to get the farmers and the consumers informed about the benefits of organic agriculture. It is on this basis that this study aim to examine the extent to which the Nigerian newspapers cover information on organic agriculture.This study was basically on coverage and content analysis of organic agricultural news in three selected Nigerian Newspapers that have been in continuous production: The Nigerian Tribune, Guardian, and Punch Newspapers. They are among the most widely read thereby having a wider coverage in Nigeria. The study covered the period of January 2010 – July 2012. Result showed that Tribune (61.9%)has the highest number of reportage while Punch (14.3%) has the least reportage. It also revealed that the three selected newspapers reported more general issues (66.7%) than the other content categories which are food safety news (19%), economic concentration news (9.5%), and environmental news (4.8%).Tribune allotted more space to organic agricultural news with 76.8% than Guardian 15.2% and Punch 8.1%.This shows that the space allotted to organic agricultural news is not encouraging, they are not reported routinely. The study revealed that there is no significant difference in the types of news of coverage onOrganic agricultural articles in the three selected Nigerian daily newspapers (F-value =0.227, p-value is=0.799), this impliess that the three selected Nigerian daily newspapers cover issues on food safety, environment, economic concentration and general issues news in the same way.The study concluded that coverage of organic agriculture is still very low and this affects the level of awareness as well as the involvement of people in the practice and the development. Thus, the study recommends that Nigeria press should be sensitive to issues on organic agriculture, that is, give adequate attention to it and publicize it on news print

An Evaluation of Property Portfolio Diversification Strategies in Nigeria.

This paper identifies diversification strategies adopted in the Nigerian property market and evaluates the effectiveness of the strategies with a view to determining the benefits of each strategy to investors and also moves the profession in Nigeria forward towards meeting the global trends. This is against the background of greater unpredictability and volatility in the Nigeria property market and the increasing need for investors to diversify risk of their portfolios. Questionnaires backed up with interviews, were administered on 28 institutional property investors in Lagos, Abuja and Port-Harcourt metropolitan areas. Pooled data on rental transactions and capital values for the period of 1998 – 2003 involving 76 properties were also collected from the investors. Data were analysed with the use of frequency distribution, relative importance index, Sharpe’s Index and mean/standard deviation ratio. The study’s results showed that “property type” and “geographic naïve diversification” were the preferred strategies in the Nigerian property market and that these strategies did not give the best protection to investors’ portfolios against the risk situation in the market. The results of the evaluation revealed that the best strategy would be to adopt efficient portfolio strategy and invest better proportions of a real estate portfolio in residential properties located in Lagos metropolitan area

Ground-State Energy Calculation of Helium Atom Using Quantum Monte Carlo CASINO-Code

We report an improved variational Monte Carlo (VMC) calculation of the ground-state energy of the helium atom, using quantum Monte Carlo (QMC) CASINO – code. The VMC ground-state energy is studied with a single determinant Slater-Jastrow trial wave-function formed from Hartree-Fock orbitals. The optimization of orbitals improved the agreement between the variational Monte Carlo and recent experiment. The calculated ground-state energy result is –2.903692762 ± 0.000023 a.u., which is in good agreement with the most recent experimental value –2.903693775 a.u. obtained by Bergeson et al. A more accurate trial function for importance sampling and the use of Jastrow–function combine to yield a ground-state energy which is 5 significant figures more accurate than that of previous quantum Monte Carlo calculations. Keywords: CASINO code, QMC, VMC, Helium atom, Reblocked-standard-erro

AN EXAMINATION OF CONTEMPORARY METHODS FOR ASSESSING COMPENSATION IN NIGERIA

The issue of compensation and how it is determined under the provisions of the Land Use Act of 1978(LUA)and its a application has been a major source of concern to professionals, academia in the real estate sector and Nigerians at large. This study examined the application of contemporary (environmental) valuation methods like contingent approach to determining compensation. One hundred and twenty (120) questionnaires were administered on claimants in Owiwi community whose farmlands and/or buildings were acquired for constructing the dam. Also questionnaire were administered on the eighteen (18) registered Estate Surveyors and Valuers in Ogun State. Both descriptive and inferential statistical tools were used in analysing the data collected from the respondents. The study revealed that the conventional approaches provided for by the statutes only captured the use values at the expense of non use values. The study therefore recommended a review of the statutes and the adoption of contingent valuation method for compensation valuation

In vitro antibacterial activity of the aqueous extract of Phyllanthus muellerianus leaves against some selected organisms

The in vitro activity of the aqueous extract of Phyllanthus muellerianus leaves against some selected organisms was investigated. The aqueous extract of P. muellerianus leaves was subjected to phytochemical screening. In addition, its antibacterial activity against clinical isolates, including Escherichia coli, Bacillus cereus, Salmonella typhi and Staphylococcus aureus was determined at 1.25, 2.50, 5.00, 10.00, 12.50, 25.00 and 50.00 mg/ml body weight in albino rats. Phytochemical screening revealed amongst others the presence of cardenolides (0.33%), cardiac glycosides (0.51%), flavonoids (0.16%), saponins (1.21%), tannins (0.68%), phenolics (0.55%) and terpenoids (0.08%). Antibacterial study revealed that the aqueous extract of P. muellerianus leaves was bacteriostatic for about 15 hours on all the tested organisms except Proteus mirabilis which showed growth at all the concentrations used. Consequently, the data in the present study indicates that the aqueous extract of P. muellerianus leaves possessed antibacterial properties, being most effective at 50.00 mg/kg body weight

Comparative analysis of the chemical composition of three spices – Allium sativum L. Zingiber officinale Rosc. and Capsicum frutescens L. commonly consumed in Nigeria

The beneficial health effects of spices against common chronic systemic diseases have been well documented. Comparative study of the proximate, mineral and phytochemical components of three spices namely garlic (Allium sativum L.), ginger (Zingiber officinale Rosc.) and pepper (Capsicum frutescens L.) were investigated. Analysis of the proximate composition revealed that the spices had considerable carbohydrate and crude protein content, but low ash, fibre, moisture and fat except pepper which has high crude fat content. The spices were also characterized by the presence of mineral elements such as calcium, iron, potassium, phosphorus, sodium, magnesium, copper and zinc which are very important to human nutrition. Phytochemical screening indicated that these spices are also rich in phytonutrients including alkaloid, tannin, carotenoids, saponin and flavonoids. The spices had low concentrations of steroids and cardenolides. Overall, the findings indicate that the spices are good sources of nutrients, mineral elements and phytochemicals which could be exploited as great potentials for drugs and/or nutritional supplements.Key words: Comparative, nutritional, supplements, spices

Development of Fingerprint Biometric Attendance System for Non-Academic Staff in a Tertiary Institution

Institutions, companies and organisations where security and net productivity is vital, access to certain areas must be controlled and monitored through an automated system of attendance. Managing people is a difficult task for most of the organizations and maintaining the attendance record is an important factor in people management. When considering the academic institute, taking the attendance of non-academic staff on daily basis and maintaining the records is a major task. Manually taking attendance and maintaining it for a long time adds to the difficulty of this task as well as wastes a lot of time. For this reason, an efficient system is proposed in this paper to solve the problem of manual attendance. This system takes attendance electronically with the help of a fingerprint recognition system, and all the records are saved for subsequent operations. Staff biometric attendance system employs an automated system to calculate attendance of staff in an organization and do further calculations of monthly attendance summary in order to reduce human errors during calculations. In essence, the proposed system can be employed in curbing the problems of lateness, buddy punching and truancy in any institution, organization or establishment. The proposed system will also improve the productivity of any organization if properly implemented. Keywords: Institution, Attendance, Biometric, Fingerprin

Evaluating Diversification Strategi Direct Property Investment Portfo

Executive Summary. This paper evaluates diversification strategies adop direct property investments in the Nigerian property market. Annual hold returns were calculated from the data on rental transactions and capital v the 1998-2003 period. Under the assumption that investments are held lon constant correlation model or excess return to standard deviation represe covariance structure of assets’ returns, the findings revealed that property geographic naïve diversification strategies underperformed most of the eff portfolios constructed using constant correlation model. Most of the perfo results were found to be statistically significant at the 0.05 level. The resu that an efficient portfolio may not be more efficient than a naïvely diversif portfolio in all cases