JBAS Articles

Journal of Basic and Applied Sciences  -   Volume 8 Number 2


Comparative Toxic Effects of Methamidophos and Cypermethrin on Cholinesterase Enzyme of Callosobruchus analis

Nighat Gul, M. Farhanullah Khan, Afaq Ahmad Siddiqui and M. Arshad Azmi

http://dx.doi.org/10.6000/1927-5129.2012.08.02.27

Abstract: In the present study the cholinesterase inhibition was observed as 65% and 12, for methamidophos and cypermethrin, respectively. LC50 values were found as 16 and 2.2, µg/cm2 for methamidophos, cypermethrin, respectively against Callosobruchus analis by the filter paper impregnation method after 24 hours of treatment. The order of efficacy was found as cypermethrin > methamidophos.

Keywords: Toxicity, Cholinesterase, Callosobruchus analis, Methamidophos and Cypermethrin

Download PDF file  :::  Back to Table of Contents

Journal of Basic and Applied Sciences  -   Volume 8 Number 2


Exploration of Multiple Intelligence by Using Latent Class Model

Shaista Ismat and Junaid Sagir Sidiqui

http://dx.doi.org/10.6000/1927-5129.2012.08.02.28

Abstract: In this article we have tried to explore, "multiple intelligence" in the educated youth through questionnaire items by applying latent class models. A questionnaire consists of 50 questions. These questions have constructed in the light of Howard Gardner theory of multiple intelligence to explore "multiple intelligence". A survey was conducted on 399 adult students from different regions of Karachi. For statistical analysis we have selected three sets with seven variables, and one set with 4 variables each with binary response.  On these four sets up to three classes latent class models were applied. The Probability of positive response (πiy) in each class were estimated by using E.M algorithm and interpreted the class as on the basis of πiy values. By assessed goodness of fit latent classes/ groups were identified. Two class (two groups of people) model was found in all four data sets. A group (class) consists of the people who think that they have strong verbal expressions abilities, effectively use language to express himself/herself theoretically and poetically, they have good ability to recognize musical pitches, tones and rhythms, we may call this class as "self competence and self esteem" as "musically talented" as "socialize" (having high interpersonal ability).

Keywords: Manifest variables, latent variable, positive response, stochastically independent, prior probability, label, likelihood, Estimation, Akaike Information Criterion (AIC), Bayesian Information Criterion (BIC).


Download PDF file  :::  Back to Table of Contents

Journal of Basic and Applied Sciences  -   Volume 8 Number 2


Pilot Plant Study to Utilize Waste Brine Generated by Salt Industries

Farhan Ullah Khan, Majid Mumtaz and Tehseen Ahmed

http://dx.doi.org/10.6000/1927-5129.2012.08.02.23

Abstract: Since early 80s, people of Pakistan have been enjoying good quality of salt known as refined salt. Mechanical salt washing is used in many countries to upgrade salt quality. The counter current washing at multiple stages and dewatering by centrifuge improves salt quality. During this process almost 10 to 15% of salt is converted into saturated brine solution containing high amount of sodium chloride, calcium, magnesium, potassium and sulphate. In the current practice most of the salt processers, this brine waste solution is drained. In the present study, a method is modified to utilize this waste brine solution. Brine was treated with calcium oxide and iron chloride to remove some soluble and insoluble impurities. The treated brine is evaporated in a specially constructed jacketed crystallizer connected with a hot water geyser. Heat is transferred through bottom by counter current flow. The temperature is maintained between 55 to 65oC at pH 3-4. The applied study yield the well shaped pyramidal crystals of salt known as Fluer de sel (flower of salt), that are world famous and used in gourmet foods with a growing market. Fleur de Sel has unique morphology, lower bulk density, large surface area, improved taste and rapid dissolution as compared to the common cubic salt

Keywords: Sodium chloride, waste brine, magnesium removal, temperature, pyramidal crystal

Download PDF file  :::  Back to Table of Contents

Chemical Properties of Carburized Mild Steel
A. Oyetunji*,1 and S.O. Adeosun*,2
1Dept of Metallurgical and Materials Engineering The Federal University of Technology, Akure Ondo State
Nigeria
2Dept of Metallurgical and Materials Engineering University of Lagos, Akoka Lagos Nigeria
Abstract: This work evaluates the suitability of using palm kernel shell, animal bone (mammalian bones from cattle) and
sea shell (oyster shell) materials as carburizers for case hardening of 0.078%C mild steel. The mild steel sample used in
this study sourced from universal steel company, Ikeja Lagos Nigeria was cut into suitable sizes using hacksaw machine
for tensile and hardness tests. The carburizing media used were milled into fine powder while Barium trioxo (iv)
carbonate (VI) (BaCO3) was used as an energizer in the carburizing process.
Three rectangular stainless steel plate boxes were fabricated to accommodate each of the steel samples and carburized.
A calculated amount of each carburizer was weighed into each of the stainless steel boxes and 20 wt % of BaC03 was
mixed with each of them. Mild steel samples were covered completely in each of the boxes with the mixture of the
carburizer and energizer placed in the furnace chamber. The carburizing temperatures varied between 700 - 1100oC
while the holding time varied between 1-5 hrs. The boxes and its contents were allowed to cool down to room
temperature in the furnace after carburization.
All samples were heated to 850oC after been soaked for 30 minutes at this temperature and oil quenched. This was to
increase the hardness of the case. Fifteen (15) of these samples were further tempered at 350oC for 2hrs to relieve the
stress built up during quenching. Hardness test, tensile strength tests and chemical analysis were carried out on the
samples. It was observed that the hardness values of the untempered samples are superior to the tempered ones at
carburizing temperatures of 7000C, 8000C and 9000C. On the other hand, the tensile strengths of the tempered samples
are higher relative to the untempered samples at carburizing temperatures of 7000C, 10000C and 11000C. The results of
the carbon analysis show that palm kernel shell and animal bone are potentially suitable to be used as a carburizing
media than the sea shell at high temperatures (above 10000C) with holding time above 1 hr.
Keywords: Carburizers, hardness, tensile, carburizing time and temperature, pack carburizing, quenching and
tempering properties.

Journal of Basic and Applied Sciences  -   Volume 8 Number 2


Toxic Effects Observed on Light Weight Proteins of Musca domestica with Pb(CH3COO)2

Rizwanul Haq, Ehteshamul Haq and M. Farhanullah Khan

http://dx.doi.org/10.6000/1927-5129.2012.08.02.21

Abstract: Lead is considered to be an important noxious waste which could contaminate the environment, such as soil, air and water, therefore, insects could be influenced easily by the lead. Musca domestica, was studied at 48 hours post treatment, under the effects of lead acetate, in different concentrations. It was observed that under the effects of lead abnormalities and deformity were developed in the larvae of flies. Thus these flies could present a useful module for the quick transmission of the environmental hazards due to lead contamination, which exerts a specific physiological and morphological effect on these flies.

Keywords: Effects, lead acetate, M.domestica.

Download PDF file  :::  Back to Table of Contents

Chemical Properties of Carburized Mild Steel
A. Oyetunji*,1 and S.O. Adeosun*,2
1Dept of Metallurgical and Materials Engineering The Federal University of Technology, Akure Ondo State
Nigeria
2Dept of Metallurgical and Materials Engineering University of Lagos, Akoka Lagos Nigeria
Abstract: This work evaluates the suitability of using palm kernel shell, animal bone (mammalian bones from cattle) and
sea shell (oyster shell) materials as carburizers for case hardening of 0.078%C mild steel. The mild steel sample used in
this study sourced from universal steel company, Ikeja Lagos Nigeria was cut into suitable sizes using hacksaw machine
for tensile and hardness tests. The carburizing media used were milled into fine powder while Barium trioxo (iv)
carbonate (VI) (BaCO3) was used as an energizer in the carburizing process.
Three rectangular stainless steel plate boxes were fabricated to accommodate each of the steel samples and carburized.
A calculated amount of each carburizer was weighed into each of the stainless steel boxes and 20 wt % of BaC03 was
mixed with each of them. Mild steel samples were covered completely in each of the boxes with the mixture of the
carburizer and energizer placed in the furnace chamber. The carburizing temperatures varied between 700 - 1100oC
while the holding time varied between 1-5 hrs. The boxes and its contents were allowed to cool down to room
temperature in the furnace after carburization.
All samples were heated to 850oC after been soaked for 30 minutes at this temperature and oil quenched. This was to
increase the hardness of the case. Fifteen (15) of these samples were further tempered at 350oC for 2hrs to relieve the
stress built up during quenching. Hardness test, tensile strength tests and chemical analysis were carried out on the
samples. It was observed that the hardness values of the untempered samples are superior to the tempered ones at
carburizing temperatures of 7000C, 8000C and 9000C. On the other hand, the tensile strengths of the tempered samples
are higher relative to the untempered samples at carburizing temperatures of 7000C, 10000C and 11000C. The results of
the carbon analysis show that palm kernel shell and animal bone are potentially suitable to be used as a carburizing
media than the sea shell at high temperatures (above 10000C) with holding time above 1 hr.
Keywords: Carburizers, hardness, tensile, carburizing time and temperature, pack carburizing, quenching and
tempering properties.