JBAS Articles

JBASV8N2A32- Fragmentation Analysis For Scalable Wireless Local Area Networks

Journal of Basic and Applied Sciences  -   Volume 8 Number 2

Fragmentation Analysis For Scalable Wireless Local Area Networks

Minhaj Ahmad Khan

http://dx.doi.org/10.6000/1927-5129.2012.08.02.32

Abstract: Wireless networks are being deployed widely to provide network connectivity without requiring the web of physical wires. A collection of a small number of workstations connected using a wireless network forms a wireless local area network (WLAN) that follows the IEEE 802.11 standard. In a WLAN, the communication takes place using packets whose sizes may vary and have a significant impact on the delay incurred during transmission. In this regard, fragmentation may play a vital role in reducing the delay for efficient transmission across the network.
This paper analyzes the performance of WLANs with respect to the packet fragmentation. We simulate three network scenarios having 4, 8 and 12 wireless workstations respectively. The scenarios are simulated using OPNET IT Guru Academic Edition v 9.1 while incorporating a peer-to-peer (P2P) based communication model for each scenario. We compare the performance of non-fragmented and fragmented communication in terms of network delay and throughput. Our results show that the fragmentation minimizes the delay and increases the throughput, however its impact is highly dependent on the size of the underlying network.

Keywords: Wireless Networks, Fragmentation, Network Delay, Network Scalability, P2P Networks

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The Effect of Grain Size on Radon Exhalation Rate in Soil Samples of Dera Ismail Khan in Pakistan

Tabassum Nasir and Nisar Ahmad

http://dx.doi.org/10.6000/1927-5129.2012.08.02.29

Abstract: Radon concentration and its exhalation rate has been measured from twenty five soil samples collected from seven different locations of Dera Ismail Khan, in the north west of Pakistan. These samples were crushed after drying and passed through sieves with different sizes of pores to get three grain sizes, £0.595 mm, 0.595-2.00 mm and 2.00-4.00 mm of soil. CR-39 based NRPB (National Radiological Protection Board) radon dosimeters have been used to measure the radon concentration and exhalation rates. The maximum average value of radon exhalation rate has found to be: (3.57±0.38) Bq m-2 hr-1 in the samples having grain size 2.00-4.00 mm and the minimum as: (2.21±0.26) Bq m-2 hr-1, in the samples with grain size £ 0.0595 mm. This indicates that the radon exhalation rate increases with the grain size. The maximum average value of radon exhalation rate has been found in samples collected from river side where soil texture is silty clay loam. The obtained values of radon exhalation rate for all the samples are well below the world average value of 57.60 Bq m-2 hr-1.

Keywords: Radon concentration, Radon exhalation rate, grain size, soil texture.

JBASV8N2A24-Effect of Packing System, Calcium Chloride and Chlorine on the Storage Life of Strawberry Fruits (Fragaria ananassa cv. Kordistan)

Journal of Basic and Applied Sciences  -   Volume 8 Number 2

Effect of Packing System, Calcium Chloride and Chlorine on the Storage Life of Strawberry Fruits (Fragaria ananassa cv. Kordistan)

Fatemeh Mozhdehi, Vahid Abdossi and Sepideh Kalatejari

http://dx.doi.org/10.6000/1927-5129.2012.08.02.24

Abstract: Effect of packing system, calcium chlorite and chlorine was evaluated on storage life of strawberry fruits. Fruits were treated with commercial grade of chlorine (calcium hypochlorite at 0, 25, 50 and 100 ppm and sodium hypochlorite at 0, 25, 50 and 100 ppm with distilled water) for one minute and then treated with different grades of calcium chlorite 0, 0.5, 1 and 1.5 percentage for five minutes, then were divided to two groups; packed and non packed with plastic cover. Then fruits were evaluated for changes in quantity parameters; pH, TA (Titratable acidity), TSS (Total soluble solids), Dry and fresh weight ratio, water content, Anthocyanin, Ascorbic acid, Ca2+, Sugar and pectin. The results showed that the packed fruits treated with calcium chloride (at 0.5 and 1 percentage) and chlorine (at 50 ppm) remained better when compared with non packed fruits. It was found that packing treatment had not a significant effect on pH. It can also deduce that packed treated fruits showed a lower TA, Anthocyanin, calcium, sugar and pectin while TSS, fresh to dry weight ratio, water content and ascorbic acid was higher in packed treated fruits.

Keywords: Strawberry, storage life, packing, post harvest, calcium chlorite, chlorine

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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.

JBASV8N2A25-The Palliative Effect of Bio-Organic Fertilizer on Lead Pollution in Lycopersicum esculentum Plants

Journal of Basic and Applied Sciences  -   Volume 8 Number 2

The Palliative Effect of Bio-Organic Fertilizer on Lead Pollution in Lycopersicum esculentum Plants

Mona M. Abdalla and Nada El-Khoshiban

http://dx.doi.org/10.6000/1927-5129.2012.08.02.25

Abstract: Lead is one of the hazardous heavy metal pollutants of the environment that originates from various sources. Soil contamination by lead reduces the quality of both soil and cultivated plants which often limits the production of some food products and animal feed. Thus, this study was undertaken to evaluate the effect of a bio-organic fertilizer, namely Acadian, a red algal extract, at recommended dose (RD) in alleviating the deteriorative effect of Pb at 0, 50, 100, 200 and 400 mg/l on tomato (Lycopersicum esculentum) plants. Accordingly, Pb-treated plants showed marked reductions in growth measurements as root and shoot length, fresh and dry weights of shoots,roots and fruits as well as number of leaves and fruits; in photosynthetic rates, stomatal conductance, net intercellular CO₂ rates (ΔCO₂) and in the contents of each of chlorophyll a, b and total chlorophyll.In addition, with the increase in level of Pb treatment in situ, total sugars, total nitrogen, catalase activity and major nutrient elements (P, K, Ca and Mg) were proportionally declined in both shoots and roots as well as proline of roots. At the other side, Pb treatment raised the levels of each of carotenoids, total soluble sugars, amino nitrogen, total soluble nitrogen, peroxidase, superoxide dismutase, phenols, lipid peroxidation, sodium, lead and iron in both roots and shoots of tomato plants as well as proline of shoots and transpiration rates. When tomato plants were supplemented with the recommended dose of Acadian solely or combined with Pb at all rates, significant increases in all measured growth parameters (shoot and root length, fresh and dry weights of shoots, roots and fruits, number of leaves and fruits), photosynthetic rates, stomatal conductance, ΔCO₂, the contents of each of chlorophyll a, b, total chlorophyll as well as the contents of total sugars, total soluble sugars, total nitrogen, total soluble nitrogen, amino-N, P, K, Ca and Mg in tomato shoots and roots were obtained. Conversely, Acadian fertilization negatively reduced the carotenoid values, the activity of antioxidant enzymes(catalase, peroxidase and superoxide dismutase), the amounts of phenol, Pb, Na, Fe and the level of lipid peroxidation in both shoots and roots of tomato plants, whereas, it positively affected transpiration rates. On the otherside, when Acadian where added to lead at different rates there were either synergistic increases in the activities of these antioxidant enzymes and the level of phenol and lipid peroxidation or decreases in the carotenoid, Na, Fe and Pb contents as well as transpiration rates. Thus, it is manifested that Acadian can be used to improve the safety, quality and productivity of lead polluted plants.

Keywords: Lead, bio-organic fertilizer, growth, gas exchange,metabolites, antioxidants, antioxidant enzymes

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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.

JBASV8N2A26-Heavy Weight Protein Affected by Lead Acetate in Bactrocera dorsalis

Journal of Basic and Applied Sciences  -   Volume 8 Number 2

Heavy Weight Protein Affected by Lead Acetate in Bactrocera dorsalis

Rizwanul Haq, M. Farhanullah Khan and Ehteshamul Haq

http://dx.doi.org/10.6000/1927-5129.2012.08.02.26

Abstract: The studies were carried out on toxic effects of lead acetate, which could contaminate the environment, such as food, water, air and soil, therefore insects could be influenced easily by the lead., Bactrocera dorsalis 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 of lead, which exerts a specific physiological and morphological effect on their bodies.

Keywords: Effects, lead acetate, Bactrocera dorsalis

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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.