Controlled synthesis of TiO2 hierarchical nanofibre structures via electrospinning and solvothermal processes : photocatalytic activity for degradation of methylene blue

The present article describes a new titanium oxide‐based (TiO2) photocatalyst that shows promise for acceleration of dye degradation. A hierarchical TiO2 nanostructure comprising nanorods on‐nanofibres has been prepared using a sol&ndash;gel route and electrospinning. Calcination of electrospun nanobre mats was performed in air at 500 &deg;C. The TiO2 nanofibre surface was then exploited as a &lsquo;seeding ground&rsquo; to grow TiO2 nanorods by a solvothermal process in NaOH. The nanofibres had a diameter of approximately 100 nm while the nanorods were evenly distributed on the nanofibre surface with a mean diameter of around 50&ndash;80 nm. The hierarchical nanostructure showed enhanced photocatalytic activity when compared to pure TiO2 nanofibres. This improved efficiency in degrading methylene blue through the photocatalytic process was attributed to the larger specific surface area of the TiO2 nanostructures, as well as high surface‐to‐volume ratio and higher reactive surface resulting in enhanced surface adsorption and interfacial redox reaction.<br /

Estimation of Annual Effective Dose and Excess Lifetime Cancer Risk from Background Ionizing Radiation Levels Within and Around Quarry Site in Okpoto-Ezillo, Ebonyi State, Nigeria

A study to estimate the annual effective dose equivalent (AEDE) and excess lifetime cancer risk (ELCR) due to background ionizing radiation (BIR) within and around Okpoto quarry site has been carried out, using a portable GQ GMC-320 Plus Geiger Counter nuclear radiation detector. An in-situ measurement of absorbed dose rate (ADR) in air at 1.0 meter above ground level was carried out at twenty different locations each for within and around the quarry site. ADR values of 0.15 µSv/hr to 0.22 µSv/hr with mean value of 0.19±0.02 µSv/hr were recorded within the quarry site and values of 0.11 µSv/hr to 0.18 µSv/hr with mean of 0.14±0.02 µSv/hr were recorded for around the quarry site. These values are observed to be slightly lower than 0.274 µSv/hr global average value. Mean values of 0.32±0.04 mSvy-1 and 0.24±0.03 mSvy-1 for the AEDE were observed respectively for within and around the quarry site. Similarly, mean values of 1.115×10-3 and 0.847×10-3 for ELCR were reported for within and around the quarry site respectively. The AEDE values are within the permissible limits as recommended by the international bodies. The ELCR values exceed the average standard value of 0.29×10-3. The implication of the AEDE and ELCR values is that the quarry site is radiation safe for any immediate radiological health burdens that might arise due to absorbed dose from BIR, but the probability of one developing cancer over a life time exposure in the quarry environment is very high. It is however recommended that periodic BIR monitoring and evaluation and radioactivity concentration of radionuclides in soil and rocks of the area be carried out by local authority, management of the quarry company and interested researchers to ascertain the absorbed dose level by workers and people living within the area from time to time. In the same vein, the time spent by workers in the excavation and quarry/crushing section of the quarry site, buyers of the quarry products, and other persons who visit the site regularly for commercial activities and sightseeing should be minimized. Keywords: Background ionizing radiation (BIR), absorbed dose, Annual effective dose equivalent (AEDE), Okpoto quarry site.

Electronic Resources Access and Usage for Scholarly Research Work by Postgraduate Students at Federal University of Agriculture, Abeokuta

This study investigated the extent of electronic resource access and usage for scholarly research work by post graduate students at University of agriculture in Abeokuta. The thrust of this paper is to discuss the points of accessing, frequency of use, usefulness and strategies to improve students’ use of electronic resources. The study adopted descriptive survey research design. The target populations for this study are postgraduate students of Federal University of Agriculture, Abeokuta, Ogun State. The participants sampled numbered 350 postgraduate students using stratified random sampling method. Out of 350 questionnaires distributed, a total of 210 were collected representing 60% return. Based on the analysis of the data, it was found that the postgraduate students use email as a means of communication while other electronic facilities that can aid their research works were not adequately used by them. Recommendations were made for improvement.  Data collected were analysed using simple percentage, frequency counts and the mean. Keywords: Electronic resources access, usage, scholarly research, University of Agriculture, Nigeri

The future of Carbon Capture and Storage (CCS) in Nigeria

Carbon Capture and Storage (CCS) is one of the techniques for greenhouse gas (GHG) emissions reduction. This article reviews the current status of CCS technology, highlights costs and discusses legal and regulatory issues of CCS. The main purpose of the article is to review CCS and CO2-EOR experience from ongoing projects in different parts of the world and give recommendations on how this knowledge can be applied in Nigeria. A potential demonstration CO2-EOR project in Nigeria under the Clean Development Mechanism (CDM) is discussed. Keywords: Carbon Capture and Storage; Clean Development Mechanism; CO2-Enhanced Oil Recovery; Nigeri

Using the Crytek Game Engine in the Technological University Dublin

It is envisaged that within the next 10 years. the Technological University Dublin (DIT), Ireland’s largest third level university, will move to a new campus in Grangegorman, located in the north inner city of Dublin This site is currently being used as a hospital. It has twelve listed buildings and is located in a densely populated urban community. This paper describes how the Crytek 3D Game engine is being used to create a game MOD (modification) of the current hospital site, how it will be used in the construction and public consultation process of the new campus and how students in the DIT are learning computer science in an new way

The Mass Media and International Terrorism

This study examines the role of the mass media in combating international terrorism. The fight against terrorism is a complex and constantly on-going one. Information pressure affects the psyche of millions of people, directs and destabilises the socio-political situation in a country and the international system. Free media are important part of the democratic society; they can contribute to the protection of the democratic freedoms. With a clear understanding of their responsibility, the media can and should contribute significantly to the rapid and successful suppression of terrorist acts. This paper seeks to shed light on the intricate relationships between government, media, and terrorism. It argues that important lessons should be learned from past actions of the media, indicating the need to develop a set of guidelines for responsible media coverage of terror. One might think that in the triangle of government, media, and terrorism, the media would side with governments in the fight against terror. Findings however indicate that this was not always the case

Password-Based Authentication and Phishing

The most common mechanism for online authenti- cation is the username-password. Majority of e- commerce applications are designed to provide pass- word authentication via an HTML form, with the assumption that the user needs to determine if it is safe to enter the password. In order to avoid phish- ing attacks, the user is expected to distinguish be- tween a phishing and a genuine website by checking the browser security indicators. Alternative authentication models suggest using images for authentication, introducing variations of Password Authenticated Key Exchange (PAKE) pro- tocols into TLS, using digital objects as passwords. Some authentication models suggest sending one- time password (OTP) tokens out-of-band to the user. Most computer users have too many passwords and keep forgetting them. Common issue for all authen- tication models is how to restore a legitimate user access to their account without authentication, i.e. password reset. In this paper, we investigate current password based authentication models and review their impact on phishing. We investigate two categories of issues 1) deployment obstacles for the \u27stronger\u27 authenti- cation models, and 2) security issues created by the number of passwords user needs to memorize