Archives-August 2012

Experimental investigations were carried out to treat tannery wastewater effluent. Various surface-active materials were used to reduce the effect of chromium present in tannery wastewater. This chemical pretreatment was followed by a biological treatment. The aim was to evaluate and optimize the various parameters effecting the chromium removal during the treatment. Different coagulants were used to suggest the efficient surface-active material during chemical pre-treatment phase and thereby the optimum time of contact, dosage and pH were determined. In this present study chemical agents had been used as a pretreatment of tannery effluent to reduce the chromium (VI) whereas the biological treatment ensures rapid reduction in the chromium ions using the bacterial degradation process.

U.S climate change policy has evolved under various administrations. It has passed through two environmental eras. In the first environmental era which started in 1960’s and ended in 1990’s main focus was on addressing environmental issues domestically by passing a number of environmental legislations. However by the end of 1990’s U.S. realized that climate change issues are beyond the control of sovereign states and only through international cooperation it can be tackled. However U.S was not willing to ratify the Kyoto Protocol, the only existing international emission reduction treaty, pointing out that it excludes developing countries from committing to binding emission reduction targets. Though Clinton administration had signed Kyoto Protocol in 1997, in 2001 George W Bush administration rejected the treaty completely. In the context of framing a new climate change treaty replacing Kyoto Protocol by world nations, if it has to be successful, at first it should ensure the participation of United States, the second largest greenhouse gas emitter. Apart from that, participation of key developing countries is also important; however their emission targets must be set up after considering their population size and per capita income.

The aim of the present study is to treat the textile effluent using Continuous Stirred Tank Electrochemical reactor [CSTER]. RuO2 coated Ti and stainless steel were used as an anode and cathode respectively. The influence operating parameter such as effluent flow rate, initial effluent concentration, current density and initial pH of the effluent has been studied for the color removal of the effluent. The maximum color removal has been achieved at lower flow rate, lower initial effluent concentration and higher current density and alkaline pH. An artificial neural network (ANN) model has been developed to predict the performance of percentage color removal by electro oxidation process based on experimental data obtained in a laboratory using Continuous Stirred Tank Electrochemical reactor. A comparison between the predicted results of the designed ANN model and experimental data matches well for the 4-3-1 net work.

The present article described the design technique of hardware electronic circuit based on modified Rossler equations. The dynamical behaviour of the proposed system has been studied by computer simulation and in electronic experiment. The results of periodic and chaotic behaviour of the hardware circuit are reported. Next the synchronization between two such electronic circuits is experimentally verified and a secure scheme of communication is described using chaos masking technique. The hardware experimental results are incorporated in this article to support the design algorithm.

This paper describes the study of coefficient of thermal expansion (CTE) of as-cast and heat treated aluminium 7075 alloys. These alloys were subjected to different aging durations. The stir casting technique is used to prepare the specimens. These specimens were machined in accordance with ASTM standards followed by heat treatment process. All the specimens were aged to different periods of 1hr, 3hr, 5hr at an aging temperature of 175 oC. Coefficient of thermal expansion tests were performed in both as-cast and heat treated conditions. In each case the coefficient of thermal expansion values were found to increase with increase in aging durations. Solution heat treatment at 530 oC followed by artificial aging at 175 oC found to increase in dimension change of every specimen tested. The coefficient of thermal expansion curves exhibited some residual strains, which were decreased with the increase in aging durations.

Network Proxy Logs contain useful user access patterns that are waiting to be discovered. By analyzing those logs, it is possible to discover various kinds of knowledge, which can then be applied to improve the performance of proxy server. Association Rule mining, by using Proxy logs, aims to discover interesting user access patterns. This paper proposes a novel approach for proxy log mining. In our approach, the Apriori Algorithm is used to extract important or useful Rules from proxy server ACCESS logs. Our paper’s aim is to mine patterns from the Network Proxy Logs and show the difference that some unauthorized clients somehow getting access to information and some authorized clients are not getting access to information. Clients who are unauthorized might be an intruder.

The issue of ethical leadership have received significant interest in recent years due to plethora of ethical scandals in organizations. Thus, this paper aims to explore for better understand the determinants of ethical leadership. Even though many researchers attempt to explore and determine the antecedents and factors of ethical leadership, yet the determinants of ethical leadership is less convincing since the results evidenced to be mixed. Together with less intention given in Malaysia to explore the determinants, hence this paper could provide a conceptual framework that would help future research endeavour.

This study examines to analyze and compare errors of concord students often conflict when speaking or writing essay. The comparison was made after 4 month of first term, examination in the case of the SS1 and SS3 classes respectively. The respondents were made up of Senior Secondary one (SS1) and Senior Secondary three (SS3) classes of Ogbemudein Mixed Senior Secondary School, Agbor, Delta State, Nigeria. Both respondents were asked to write an essay twice with four months interval on the same topic. In each writing sessions, there were 60 essays written by respondents, giving a grand total of 120 essays being analyzed. The results showed an increase in errors resulting to 3.40% among students in the senior secondary one (SS1) but with drastic reduction of 10.48% among the Senior Secondary three (SS3) which of course performed below expectation.

The [Persian] Gulf cooperation council (GCC) was funded on May 25, 1981 by six littoral Persian Gulf states just two years after the occurrence of the Islamic revolution in Iran in 1979. This article explains the interaction between Islamic Republic of Iran and the GCC member states (Saudi Arabia, Kuwait, UAE, Oman, Qatar and Bahrain). In the first part this article is going to summarize the main reasons of founding the GCC since 1981 and explains the interaction between Iran and the [Persian] Gulf Cooperation Council and the influence of the decisions of GCC on Iran’s security policies during the past thirty years; and in third part, we will evaluate the workbook of the GCC conservative states regarding to Iran and influences of struggle between Iran and the GCC states. At the end, according to the results of the research, writers will recommend some new parameters that must be considered to maintain peace and security in the Persian Gulf region.

One group of pesticides that play an important role after the ban of the persistent organochlorine pesticides in agriculture is synthetic pyrethroids pesticide. Synthetic pyrethroids mimic the broad efficacy of the botanical, but they contain only one of the six groups of esters of the natural pyrethrums, and insect species tend to develop resistance to them. However, the latest groups of synthetic pyrethroids are photo-stable, as well as extremely toxic to insects. The objective of this study is to determine residue levels of selected synthetic pyrethroids pesticides in cocoa beans produced in Ghana, and to assess these levels against the European Union and Japanese residue regulation limits. The determination was done by gas chromatography coupled with an electron capture detector, and confirmed with Saturn 2200 Mass Spectrometer using ion trap mass analyzer. The study revealed the presence of all nine selected synthetic pyrethroids pesticides at significantly varying concentrations, with Permethrin recording the widest range of residue concentration from not detected to 105.0 micrograms per kilogram. The percentage recovery for most of the pesticides ranges from 75 to 120 percent, with method determination limit of 5.0 micrograms per kilogram. None of the detected synthetic pyrethroids pesticides’ average residue concentrations did exceed the European Union or Japanese Maximum Residue Limits in cocoa beans produced in Ghana. However, Allethrin, Cypermethrin and Fenvalerate average residues concentrations were at the borderline of the Japanese MRLs.