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This research was carried out to monitoring natural radioactivity level in rock samples were taken from Northern Nuba Mountain, Dallanj region - South Kordofan State. Gamma ray spectroscopy technique was used to evaluate radioactivity level to establish background radiation level. Measured activity concentrations of radionuclides 226Ra,232Th and 40K ,absorbed dose and annual effective dose were found 23.56±2.11, 29.57±4.33 and 330.58±37.06 Bqkg-1 and 33.34±3.39 nGyh-1 and 40.92±4.16 µSvy-1 , respectively. The obtained data shown that values are far below than reported global data. Estimation of the relative contribution of the 226Ra, 232Th and 40K to the overall absorbed dose in air discovered that the main contribution comes from 232Th 53.57 %.

In order to solve the reliability assessment of repairable systems, this article, based on two-component system, provides the maximum likelihood estimation. The system can be restored through proper repairing even from Common Cause Shock (CCS) failure. We derived M L estimates of availability for series and parallel systems. The approach used is empirical one with Monte Carlo simulation.

Extensive field and site investigations were conducted to assess and evaluate the situation in the presently exploited quarries of cement raw materials in Yemen. These quarries have several geological complications represented mainly by high elevations, steep slopes, rugged topography, heterogeneity in bed thickness, lithologic composition and quality, presence of igneous sills and dykes, intensive fracturing and jointing and abundance of karstification features. Moreover, the processes of quarrying and related operations have several negative environmental impacts the most important of which are soil failure, overburden and land sliding, toppling and rock falls (which result in considerable mass wasting) and emission of dust and noise. Generally, quarrying operations are more hazardous in quarries of gypsum and basement rocks than in those of carbonates and volcanics. Furthermore, the quarries have problems related to the conservation of natural resources. These are represented primarily by the excavation of the valuable agricultural and reclaimed lands and improper exploitation of the cement raw materials and the fresh and underground waters the reserves of which decreased drastically. To deal with the above-mentioned problems, a number of recommendations are outlined. They comprise mitigation measures which must be strictly implemented. Also, it is of almost importance to conduct prospecting for new occurrences of the presently exploited cement raw materials and their possible substitutes as well as additional groundwater resources.

The role of corporate board of directors in aligning the interest of diverse groups, ensuring discipline and effectiveness among board members cannot be over emphasised, although there are limited empirical investigations on African firms and Nigeria in particular about the nature of the relationship between board variables and firms financial performances. This study apply Pearson correlation and regression analyses to examined the relationship between board composition (proportion of; non-executive directors, executive directors and women directors) and corporate financial performance for a sample of commercial banks in Nigeria. Using two financial performance indicators; return on asset and return on equity from 2008-2012, the study find out that board composition as defined above is not related to corporate financial performance.

The Photocatalytic process is one of the important green engineering concepts employed for treating the waste water from industries. This paper presents an overview of Photocatalytic degradation of textile effluents in industries by titania (TiO2). TiO2nanocatalystwas synthesized using sonochemical method. This Nanocatalyst was characterized using SEM, XRD &TGA. An Effluent from the textile contains hazardous compounds such as ethyl sulphonic and sulphonic groups which cause severe water pollution. Photocatalytic degradation using Tio2nanophotocatalyst based adsorbent as a semiconductor in a batch reactor. Experiments were performed to observe the extent of photocatalytic degradation of textile effluents by analyzing different parameters. The effluents were degraded and nearly 96% of colour reduction was observed. Experiments were also conducted to optimize the amount of catalyst used during this process. This process is a very effective green engineering concept and a cheapest for treating the textile effluents using TiO2 before disposing it off into water.

Azanza garckeana is a wild edible indigenous fruit tree species in western Sudan locally named (Jakhjakh). The physiochemical and analytical study of Azanza garckeana fruit, physical parameters of fruits determined length ranges 2.52 – 3.52 cm, Width 2.07 – 2.68 cm, Thickness 2.00 – 2.72 cm, Weight 4.05 – 7.98 g, Edible part + peels 2.89 – 5.92 g, Seeds 1.15 – 2.06 g. The chemical contents Crude Protein 9.21%, Moisture 3.82%, Fat 1.19%, Crude Fiber 45.23%, Ash 22.2%, Carbohydrates 42.17%, Energy Value 219.28%, Total Sugar 31.36%, Reducing Sugars 17.72%, Total treatable acidity 0.13%, Vitamin C 41.92%, B-carotene(IU/100g) Vitamin A 18.50% and Pectin 0.26%. The elements determined using ICP-OES the metal levels are decreasing in order Sr > Mn > Ti > Ba > As > Zn > Cu > Cr > V > Co. And essential elements found in higher level order degrease as Ca > K > Mg > P > Na > Si > Fe > Al > Li = Be.

Thisstudy compares the heat transfer coefficients for film and dropwise condensation of steam.Copper tube was coated with oleic acid to promote dropwise condensation of steam rather than a continuous film. Excellent dropwise condensation was observed when the cooling surface was coated with oleic acid, and this helps to enhance droplet formation without wetting the surface.The experimental results shows that the value of overall heat transfer coefficient is 50000 W/m2K in dropwise and 12500W/m2K in filmwise condensation.Thus, theoverall heat transfer coefficients during dropwise condensation are approximately four times greater than those during filmwise condensation at the same surface subcooling degrees.

Neurological researchers have recently revealed their findings about increasingly common and sophisticated role of Artificial neural networks (ANNs). That applied for systematic realistic modeling of interdisciplinary discipline incorporating neuroscience, education, and cognitive sciences. Accordingly, ANN Models vary in relation to the nature of assigned brain functioning to be modeled. For example, as human learning takes place according to received stimuli that is simulated realistically through self-organization paradigm by artificial neural networks modeling. This piece of research adopts the conceptual approach of (ANN) models inspired by functioning of highly specialized biological neurons in reading brain based on the organization the brain's structures/substructures. Additionally, in accordance with the prevailing concept of individual intrinsic characterized properties of highly specialized neurons, presented models closely correspond to performance of these neurons for developing reading brain in a significant way. More specifically, introduced models concerned with their important role played in carrying out cognitive brain function' outcomes. The cognitive goal for reading brain is to translate that orthographic word-from into a spoken word (phonological word-form). In this context herein, the presented work illustrates via ANN simulation results: How ensembles of highly specialized neurons could be dynamically involved in performing the cognitive function of developing reading brain.

The detection rate of pancreatic cystic lesions has increased since the current use of high resolution imaging. CT-scan, MRI and echo-endoscopy are diagnostic modalities. The pseudocyst is the most common lesion. It is benign and can be managed by endoscopic treatment. Pancreatic cancer accounts for 2% of all tumors, yet it is the fifth leading cause of cancer death. The surgical treatment of these lesions should be discussed within a multidisciplinary team. The interest of this observation lies in the rarity of the published case, both in terms of the location of the tumor and the clinical and radiological presentation leading to a benign tumor of the pancreas which sometimes poses diagnostic difficulties and justifies a discussion multidisciplinary.

This paper examines the ‘O’ level mathematics themes specifically to identify the most difficult content areas in order to improve students’ achievement in mathematics. In this study, questionnaire made up of the content areas in ‘O’ level mathematics were administered in classrooms using random sample technique. The sample consists of 214 students; 102 males and 112 females of some selected Secondary schools in Nasarawa State. The respondents are all SS III students of 2012/2013 academic session. The data collected was analysed using simple arithmetic percentages. It was established that a great number of the respondents perceived Plane Geometry as the most difficult content area in “O” level mathematics and this constitute 80 (37.4%) of the 214 respondents. This is followed by 55 (25.7%) of the respondents who are of the view that Algebraic Processes is the most difficult.