76 research outputs found
Inhibition effect of potassium dichromate on the corrosion protection of mild steel reinforcement in concrete
The inhibition of potassium dichromate on the corrosion protection of mild steel embedded in concrete
and partially immersed in sulphuric acid and sodium chloride environments was evaluated at ambient
temperatures. The experiments were performed using electrochemical potential monitoring method.
Varying quantities of the inhibitor was used. In the NaCl test medium, the effectiveness of the inhibitor
improved as higher concentration was used. The best inhibition was achieved in the reinforced
concrete sample admixed with 9 g potassium dichromate. Steel-reinforced concrete sample admixed
with 3 and 9 g potassium dichromate inhibitor had the highest improvement in compressive strength.
The potassium dichromate inhibitor was most effective amongst other inhibitor concentrations used
when 7.5 g was admixed with the sample in the H2SO4 medium. The sulphuric acid medium had a
deleterious effect on the strength of concrete test specimens
FORMATION OF TOXIC NITROSAMINE AS A COMPLICATION OF PROSTATIC HYPERPLASIA ASSOCIATED WITH URINARY TRACT INFECTION AND URINARY RETENTION.
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The formation of urinary dimethylinitrosamine [DMN] in male patients with benign prostatic hyperplasia [BPH]
associated with urinary Tract infection [UTI] was investigated in patients presenting with Klebsiella species infected
bladder secondary to [UR]. Specimens from the patients were analysed qualitatively and quantitatively for DMN
while blood samples from the same patients were investigated for the activities of common liver enzymes such as
alanine transaminase [ALT] and alkaline phosphatase [ALP]. Blood analysis for bilirubin, albumin, total protein
content and for creatinine were also carried out. The results obtained in the infected subjects (when compared with
those of a healthy group) showed significant mean values of DMN, ALP, AST as 0.12± 0.09mgNO2/L; 36 ± 1.7iu/L;
7i.u/L respectively (P < 0.05). The values obtained for bilirubin, albumin, total protein, creatinine and ALT were not
significantly different from those of control subject
Applications, Energy Consumption and Measurement
The task of reducing the energy footprint of IT devices and software has been a challenge for Green IT research. Monitoring approaches have primarily focused on measuring the energy consumption of the hardware components of computing devices. The use of applications or software on our computer systems consumes energy and it also affects how various hardware components and system resources consume energy. Consequently, running web browsers applications will utilise considerable energy and battery consumption. In this research, we have run different types of experiments which involve the use of several measuring tools. Firsly, a joulemeter is used to monitor (and measure) the power consumed by the hardware and software while running web-based and stand-alone applications on several devices. Additionally, the tablet in-built battery status checker is used to measure the battery consumption when web-based applications are run on the device
Experimental Assessment of Cellular Mobile Performance along the Railway Corridor
With the ongoing rehabilitation of the railway transportation sector in Nigeria, improvement in the quality and reliability of the services deliverable becomes crucial. Reliable railway communication infrastructure guarantees effective operation and also ensures connectivity for security, safety, maintenance and passenger communication. This work describes today’s network scenario by assessing current cellular performance as it affects a passenger’s experience along the railway corridor. A drive test was conducted on the 6th of July, 2014 between 12:58pm and 07:14pm along the railroad linking Oshogbo and Lagos, Nigeria. The measurement setup consists of four TEMS Mobile Sony Ericsson W995 phones, a Personal Computer, a GPS receiver, and a power bank. The measurement was useful in the assessment of coverage, capacity and Quality of Service (QoS) of four mobile radio networks namely: Airtel, Globacom, Etisalat and MTN in the GSM 900 MHz and 1800 bands. Results reveal that no single mobile network service operator consistently serviced the train throughout the 6-hour trip. Also, the results obtained from the drive test represents a true picture of mobile network condition and can be useful in decision making in several areas - from planning and design through optimization and maintenance of the system, with the goal of maximizing quality, capacity and coverage for all mobile networks for improved service delivery on our railway infrastructure.
Keywords: Railway communication; GSM; Performance of Cellular mobil
Biochemical and Histological Responses of Hepatotoxic Rats Fed Musa paradisiaca L. Supplemented Diet
Some biochemical and histological effects of consumption of Musa paradisiaca-supplemented diet in hepatotoxic rats were investigated. Twenty-four rats were divided into four hepatotoxic and non-hepatotoxic groups and fed a Musa paradisiaca-supplemented diet. The parameters measured included alanine transaminase, aspartate transaminase, total protein, glucose, total triglycerides, total cholesterol, reduced glutathione, lipid peroxidation and packed cell volume. Histological changes in tissue sections of liver and testes were also examined. The results obtained showed that alanine transaminase and aspartate transaminase did not significantly change except in the hepatotoxic control group which showed an increase in aspartate transaminase. Cholesterol and triglycerides were significantly (p<0.05) increased in the hepatotoxic group fed Musa paradisiaca-supplemented diet. Protein and reduced glutathione levels were significantly (p<0.05) increased in non-hepatotoxic rats fed Musa paradisiaca-supplemented. Lipid peroxidation, glucose and PCV levels were not significantly altered in all the groups. The consumption of a Musa paradisiaca-supplemented diet did not significantly change the weight of the animals. Histological observations of tissue sections of liver showed necrosis in the hepatotoxic rats and varying regeneration in the groups fed Musa paradisiaca-supplemented diet while there were no changes in the histology of the testes in all the groups
Understanding the dynamics of inflation volatility in Nigeria: A GARCH perspective
The estimation of inflation volatility is important to central banks as it guides their policy initiatives for achieving and maintaining price stability. This paper employs three models from the Generalized Autoregressive Conditional Heteroscedasticity (GARCH) family with a view to providing a parsimonious approximation to the dynamics of Nigeria’s inflation volatility between 1996 and 2011. Of the competing models, the asymmetric TGARCH (1,1) provides an appropriate paradigm for explaining the dynamics of headline and core CPI volatilities in Nigeria, while the symmetric GARCH (1,1) was found to be adequate for food CPI. The results are quite revealing. Firstly, model outcomes indicate high persistence parameters for the core and food CPI, implying that the impacts of inflation shocks on their volatilities die away very slowly. However, the impact of inflation shocks on headline volatility die out rather quickly. Secondly, substantial evidence of asymmetric effect was found for both headline and core inflation types while the contrary was confirmed for food inflation. Thirdly, positive inflationary shocks yielded higher volatilities in headline and core inflation than negative innovations, implying the absence of leverage effect in them. The paper finds that periods of high inflation volatility are associated with periods of specific government policy changes, shocks to food prices and lack of coordination between monetary and fiscal policies
Degradation Evaluation of Zinc m 2 M Hydrochloric Acid m the Presence of Bambusa bambos
Failure evaluation of zinc sample in 2 M hydrochloric acid solution in the presence of
Bambusa bambos extract was conducted using the gasometric method. Zinc coupons, each
measuring 2.5 by 1.5 em were completely immersed in uninhibited and inhibited test solutions
containing extract quantities of 60, 100 140 and 180 mL at a temperature of 298 K for 20 minutes.
The volumes of hydrogen gas data obtained during the experiment were documented and analyzed.
Results showed that maximum inhibitor efficiency and lowest corrosion rate were obtained at
extract quantities of 140 and 100 mL, respectively while corrosion rate reduction did not follow any
particular trend. Frumkin isotherm best explained the extract-metal surface interaction adsorption
mechanism. Once quantity of the extract is known, an expression for estimating corrosion rate
values was also obtained. In addition, the surface analysis indicated that the rate of deterioration
of the metal reduced as extract quantity increased to some extent and changed thereafter
Understanding the dynamics of inflation volatility in Nigeria: A GARCH perspective
The estimation of inflation volatility is important to central banks as it guides their policy initiatives for achieving and maintaining price stability. This paper employs three models from the Generalized Autoregressive Conditional Heteroscedasticity (GARCH) family with a view to providing a parsimonious approximation to the dynamics of Nigeria’s inflation volatility between 1996 and 2011. Of the competing models, the asymmetric TGARCH (1,1) provides an appropriate paradigm for explaining the dynamics of headline and core CPI volatilities in Nigeria, while the symmetric GARCH (1,1) was found to be adequate for food CPI. The results are quite revealing. Firstly, model outcomes indicate high persistence parameters for the core and food CPI, implying that the impacts of inflation shocks on their volatilities die away very slowly. However, the impact of inflation shocks on headline volatility die out rather quickly. Secondly, substantial evidence of asymmetric effect was found for both headline and core inflation types while the contrary was confirmed for food inflation. Thirdly, positive inflationary shocks yielded higher volatilities in headline and core inflation than negative innovations, implying the absence of leverage effect in them. The paper finds that periods of high inflation volatility are associated with periods of specific government policy changes, shocks to food prices and lack of coordination between monetary and fiscal policies
Assessing the deterioration behaviour of mild steel in 2 M sulphuric acid using Bambusa glauscescens
The study investigated the deterioration of mild steel in 2 M sulphuric acid solution in the
presence of Bambusa glauscescens extract using gasometric technique. Steel coupons
measuring 4 cm by 1.5 cm were immersed in test solutions of uninhibited acid and also those
containing extract concentrations of 60,100 and 140 cm3 at a temperature of 333K for 60
minutes. The volumes of hydrogen gas evolved from the reaction were documented and
analyzed. The analysis showed that while extract concentration was increasing, H2 evolution
and % I.E increased. There was also a corresponding reduction in corrosion rate as extract
concentration increased. The decrease in corrosion rate was observed to follow in order of
increasing extract concentration. Phytochemical-metal interaction mechanism was best
described by Freundlich isotherm, with the 4 and 12 minutes curve becoming the best and
worst contact time for the extract phytochemicals to suitably adsorb to metal surface for all
concentrations used. An expression suitable for calculating corrosion rate values once
concentration is known was also deduced. Furthermore, the microstructural studies revealed
that increasing the extract concentration resulted in significant reduction in the dominant
coarsening of the oxide of iron phase, while the pearlite and ferrite phases became finely
disperse
Understanding the dynamics of inflation volatility in Nigeria: A GARCH perspective
The estimation of inflation volatility is important to central banks as it guides their policy initiatives for achieving and maintaining price stability. This paper employs three models from the Generalized Autoregressive Conditional Heteroscedasticity (GARCH) family with a view to providing a parsimonious approximation to the dynamics of Nigeria’s inflation volatility between 1996 and 2011. Of the competing models, the asymmetric TGARCH (1,1) provides an appropriate paradigm for explaining the dynamics of headline and core CPI volatilities in Nigeria, while the symmetric GARCH (1,1) was found to be adequate for food CPI. The results are quite revealing. Firstly, model outcomes indicate high persistence parameters for the core and food CPI, implying that the impacts of inflation shocks on their volatilities die away very slowly. However, the impact of inflation shocks on headline volatility die out rather quickly. Secondly, substantial evidence of asymmetric effect was found for both headline and core inflation types while the contrary was confirmed for food inflation. Thirdly, positive inflationary shocks yielded higher volatilities in headline and core inflation than negative innovations, implying the absence of leverage effect in them. The paper finds that periods of high inflation volatility are associated with periods of specific government policy changes, shocks to food prices and lack of coordination between monetary and fiscal policies
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