The physical basis of the method of differential thermal analysis

In the present study, it is intended to concentrate on Stefan Problems exclusively, and to attempt a partial solution making use of experimental data relating to (a) the temperature distribution in a finite medium of given shape before, during, and after a thermal reaction, and (b) the rate of propagation of such a reaction through the medium. For this type of problem a number of analytical solutions have appeared(27 - 36), but so far only the solution for semi -infinite media has been carried to a stage suitable for numerical calculation. The essential feature of the problem is the existence of a moving boundary at which heat is generated or removed, and one obstacle to complete solution is that the history of this interface as it moves is unknown. To determine the history (a space - time curve) of the interface, it is necessary to solve the heat equation, which is a linear homogenous parabolic equation, with the appropriate boundary conditions and with a suitable discontinuity in the first -order space derivatives across the unknown interface(37). Such a solution, in most cases, is either very difficult or impossible

E-GOVERNANCE, REVENUE GENERATION AND PUBLIC SERVICE DELIVERY IN NIGERIA: AN OVERVIEW OF THE E- TAXATION SYSTEM IN LAGOS STATE

In the early 90s, e-governance became a global pursuit towards improving public service delivery. Nigeria joined the bandwagon of the e-governance drive in year 2000, when the government realized the need to adopt e-governance to improve public service delivery. This paper attempts to look at the implementation of e-governance in Nigeria, in relation to e-taxation in Lagos state. It examines the capacity of the Lagos state government to utilize Information, communication and technology (ICT) devices to generate revenue and block revenue leakages. The study is empirical in nature, making use the survey method (questionnaires) to gather data. Descriptive statistics were employed to analyze responses from the respondents, and the Chi-Square statistical method of analysis was used to test the hypotheses formulated. The study revealed that despite the huge investment of state government on ICT to realize these objectives little progress has been achieved. This can be attributed to infrastructural gap, power failure, digital divide, low ICT literacy level, theft and vandalizations of ICT equipment, poor enlightenment among others. The study concludes that the emerging growth and adoption of e-taxation in Lagos state has not significantly improved its revenue generation. Hence, among the suggestions proffered by the paper is that the state government should partner with software providers to provide smart phones for tax payers at minimum cost to ease tax payments via ICT with Tax Identification Numbers (TIN). Key words: E-governance, Public service, Economic growth, E-taxation, Tax management, Tax avoidance, Tax evasion

The Efficacy of using Gravity Concentration Methods in Value Addition to Ajabanoko Iron Ore for use in Nigerian Smelting Plants towards Metallurgical Purposes

This research work x - rays the use of gravity separation methods – Wifely shaking tabling and Air flotation (Kip Kelly air floating machine) to produce a high iron ore concentrate that could be used in both Blast furnace and Direct Reduced Induction (DRI) operation as a feed towards the production of Nigerian iron and steel. Crude iron ore assaying 40.72%Fe was beneficiated by using dry air floating processing method and wet wilfley shaking tabling process after characterization and the determination of liberation size of the iron ore and grinding of the crude iron ore to this liberation size of -500 + 355µm.The result revealed that the use of Air floating method gave 67.95%Fe, low acid oxide gangue of 7.3%, while Wilfley shaking tabling gave 51.16%Fe, low acid oxide gangue of 18.6%. It does shows that Air float tabling machine met the required standard grade of iron (≥ 65%Fe) content needed as a charge for the furnace operation, while, the assay and recovery obtain of wilfley shaking tabling could not meet the standard requirement for iron and steel production in the country, Nigeria

Isothiourea-catalysed acylative kinetic resolution of aryl-alkenyl (sp2 vs. sp2) substituted secondary alcohols

We would like to thank the Engineering and Physical Sciences Research Council and CRITICAT Centre for Doctoral Training [Ph.D. studentship to S.F.M.; Grant code: EP/L016419/1 and EP/J018139/1] and The Leverhulme Trust [Early Career Fellowship to J.E.T.; ECF-2014-005] for financial support. A.D.S. thanks the Royal Society for a Wolfson Merit Award.The non-enzymatic acylative kinetic resolution of challenging aryl–alkenyl (sp2 vs. sp2) substituted secondary alcohols is described, with effective enantiodiscrimination achieved using the isothiourea organocatalyst HyperBTM (1 mol %) and isobutyric anhydride. The kinetic resolution of a wide range of aryl–alkenyl substituted alcohols has been evaluated, with either electron-rich or naphthyl aryl substituents in combination with an unsubstituted vinyl substituent providing the highest selectivity (S=2–1980). The use of this protocol for the gram-scale (2.5 g) kinetic resolution of a model aryl–vinyl (sp2 vs. sp2) substituted secondary alcohol is demonstrated, giving access to >1 g of each of the product enantiomers both in 99:1 e.r.Publisher PDFPeer reviewe

Gender Diversity in the Governance of the Nigerian Security Market

The purpose of the paper is to identify the key determinants of stock market performance in Nigeria. More specifically, it is an attempt to determine the effect of gender diversity in leadership roles on the performance of the stock market in Nigeria. The paper uses annual data from 1980 through 2011 to model the development and performance of the Nigerian stock market through a modified Calderon-Rossell approach. Specifically, the leadership role of women in the governance of the stock market is investigated. Robust regression approach is used to avoid complications associated with the violations of the assumptions underlying the application of ordinary least squares regression. The empirical analysis shows that level of income, real exchange rate, liquidity, banking sector development, institutional quality, macroeconomic stability and gender are important determinants of stock market performance in the Nigerian stock market. Further, the results indicate that at worst, gender diversity does not play into stock market performance in Nigeria, and at its best, the appointment of women in the management of the Nigerian Stock Exchange is associated with better performance. The paper contributes to the empirical literature on the role of gender diversity and financial performance. The contribution of this paper is the inclusion of gender as an institutional factor among the determinants of stock market performance in Nigeri

The network structure of visited locations according to geotagged social media photos

Businesses, tourism attractions, public transportation hubs and other points of interest are not isolated but part of a collaborative system. Making such collaborative network surface is not always an easy task. The existence of data-rich environments can assist in the reconstruction of collaborative networks. They shed light into how their members operate and reveal a potential for value creation via collaborative approaches. Social media data are an example of a means to accomplish this task. In this paper, we reconstruct a network of tourist locations using fine-grained data from Flickr, an online community for photo sharing. We have used a publicly available set of Flickr data provided by Yahoo! Labs. To analyse the complex structure of tourism systems, we have reconstructed a network of visited locations in Europe, resulting in around 180,000 vertices and over 32 million edges. An analysis of the resulting network properties reveals its complex structure.Comment: 8 pages, 3 figure

Geophysical Investigation of Part of Ahmadu Bello University Farm, Nigeria

Geophysical methods are becoming an increasingly valuable tool even for agricultural applications. Agricultural  geophysics investigations are commonly focused on delineating small- and/or large-scale objects/features within the soil profile (````````~ 0 to 2 m depth) over very large areas. The study was carried out at a farm site in Ahmadu Bello University, to delineate subsurface structures with depth. It revealed the lithological units in the study area. The analyses has revealed various lithological units from the results of the inverted sections along the profiles. The study area has shown clearly two distinct layers, overburden and weathered basement. The overburden layer is clayey sand, sandy clay, and laterite. This laterite soil show very high resistivity anomaly that may be referred to as consolidated laterite. The weathered layer which contains medium grained sand with clay and feldspar materials also has the presence of fractured part that could act as the aquifer in the area. From the subsurface properties, this farm land may have low agricultural yield or may limit the cultivation potential of the region, but the region may be good for underground water yield

The Seroepidemiology of Haemophilus influenzae Type B Prior to Introduction of an Immunization Programme in Kathmandu, Nepal.

Haemophilus influenzae type b (Hib) is now recognized as an important pathogen in Asia. To evaluate disease susceptibility, and as a marker of Hib transmission before routine immunization was introduced in Kathmandu, 71 participants aged 7 months-77 years were recruited and 15 cord blood samples were collected for analysis of anti-polyribosylribitol phosphate antibody levels by enzyme-linked immunosorbent assay. Only 20% of children under 5 years old had levels considered protective (>0.15 µg/ml), rising to 83% of 15-54 year-olds. Prior to introduction of Hib vaccine in Kathmandu, the majority of young children were susceptible to disease