JBAS Articles

Journal of Basic and Applied Sciences  -   Volume 8 Number 2

Immobilization of Leuconostoc-paramesenteroides Dextransucrase Enzyme and Characterization of its Enzyme Properties

Amal M. Hashem, Mona A. El-Refaei, Hasan M. Gebril and Ahmed F. Abdel-Fattah

http://dx.doi.org/10.6000/1927-5129.2012.08.02.16

Abstract: Dextransucrase from Leuconostoc-paramesenteroides was immobilized using different immobilization techniques. Entrapment in calcium alginate (2%) proved to be the most suitable technique (27.6% yields). The operational stability of the immobilized was retained 100% until 11 cycle, with decreasing of 70%, of the retained activity at 13 cycles. The specific activity of the free was compared to that of the immobilized enzyme. The optimum temperature of the free enzyme was 65°C were as it was 70°C with the immobilized enzyme. The specific activity of the immobilized was higher than that of the free enzyme at pH 4. 100% of the specific activity was retained due to the thermal stability of the immobilized enzyme after heat treatment for 60 minutes at 60°C. The activation energy (EA) of the immobilized enzyme was lower than that of the free enzyme (EA= 10.3 and 12.13 Kcal/mol respectively). The calculated half-lives of the free enzyme at 40, 50, 60 and 70 were 15.0, 4.68, 4.68 and 4.0 min respectively which were lower than those of immobilized enzyme i.e. 401, 385, 295 and 42 min, respectively.

Keywords: Dextransucrase, enzyme immobilization, calcium alginate, Leuconostoc.

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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

 Arbuscular Mycorrhizal Colonization in Five Tropical Forest Tree Legumes of Chittagong University Campus in Bangladesh

 Nure Ferdousee, Khaled Misbahuzzaman and A.T.M. Rafiqul Hoque

 http://dx.doi.org/10.6000/1927-5129.2012.08.02.17

Abstract: Arbuscular mycorrhizal (AM) colonization in five tropical forest tree legumes (Gliricidia sepium, Dalbergia sissoo, Indigofera tysmanii, Delonix regia and Samanea saman) was investigated in Chittagong University (CU) campus. The results of the present study clearly suggests that, Vesicular AM fungi (VAM) are common in all the studied forest tree species, and that the studied forest tree species differ in their rates of AM formation. The intensity of colonization is maximum (98%) in I. tysmonii followed by D. sissoo (95%), D. regia (63%), S. saman (59%) and G. sepium (52%). Coiled structures of hyphae were recorded in D. regia. Arbuscule formation was recorded in D. sissoo and in I. tysmonii. Mycorrhizal spores were found in rhizosphere soils of all the sites. Glomus, Acaulospora, Entrophospora and Gigaspora spores were identified in all the hosts. Forest plants differ in their rates of AM formation. Edhapic conditions like moisture content, soil pH also influence the extent of root colonization.

Keyword: Mycorrhizae, Legume, Colonization, Edhapic condition, Rhizosphere, Underground networking.

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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

Hazardous Effects of Lead Acetate on Heavy Proteins of Bactrocera zonata

Rizwan ul Haq

http://dx.doi.org/10.6000/1927-5129.2012.08.02.19

Abstract: Lead is presume to be an important toxic waste which contaminate the environment, therefore, insects could be influenced easily by the lead., Bactrocera zonata 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 malformation 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, Proteins, Bactrocera zonata.

 

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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

Evaluation of Basic Data Compression Algorithms in a Distributed Environment

Minhaj Ahmad Khan

http://dx.doi.org/10.6000/1927-5129.2012.08.02.18

Abstract: Data compression methods aim at reducing the data size in order to make data transfer more efficient. To accomplish data compression, the basic algorithms such as Huffman, Lempel-Ziv (LZ), Shannon-Fano (SF) and Run-Length Encoding (RLE) are widely used. Most of the applications incorporate different variants of these algorithms. This paper analyzes the execution times, compression ratio and efficiency of compression methods in a client-server distributed environment. The data from a client is distributed to multiple processors/servers, subsequently compressed by the servers at remote locations, and sent back to the client. Our experimentation has been carried out using Simgrid Framework. Our results show that the LZ algorithm attains better efficiency/scalability and compression ratio, however, it works slower than other algorithms.

Keywords: Distributed Computing, Compression, LZ, Shannon-Fano, RLE, Huffman, Scalability.

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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

Investigating the Influence of Cosmic Rays on Ozone Layer Depletion at Beijing, China

Bulbul Jan and M. Ayub Khan Yousuf Zai

http://dx.doi.org/10.6000/1927-5129.2012.08.02.20

Abstract: In the present study monthly and annually data of ozone depth and cosmic rays (CRs) intensity at China Beijing during the period of 1984-2010 have been analyzed to investigate the effects of cosmic rays intensity on ozone layer depletion (OLD). This communication implements statistical analysis on the data sets for the specified period mentioned above. The analyses exhibit that mean monthly variation of cosmic rays intensity increases. Our investigation claims that in the month of May (1984-2010) changes occurred in the decrease the ozone depth due to the increase in cosmic rays intensity .This sort of study confirms cosmic rays influence on the ozone layer depletion.

Keywords: Cosmic rays, Ozone depletion, Climate change.

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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.
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  2. JBASV8N2A11 - Effects of Carburizing Process Variables on Mechanical and Chemical Properties of Carburized Mild Steel
  3. JBASV8N2A12 - Sustainable Agricultural Practices as Perceived by Farmers in Sindh Province of Pakistan
  4. JBASV8N2A13 - Effect of Hot Water Treatment on the Chemical, Sensorial Properties and Ripening Quality of Chaunsa Mango (Mangifera indica L.)