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Science Journal

 

Academia Arena

 学术争鸣

Volume 4 - Number 2 (Cumulated No. 32), February 25, 2012, ISSN 1553-992X, Monthly

Cover Page (online), Cover (print), Introduction, Contents, Call for Papers, All papers in one file

Welcome to send your manuscript(s) to: editor@sciencepub.net.

CONTENTS

No.

Titles / Authors

Text

No.

1

Extrinsic Factors Influencing Antibacterial Activities of Tapinanthus bangwensis Against Diarrhoeal Causing Organsims

 

B.T. Thomas1, H. I. Effedua2, G.C. Agu5, O.S. Musa, P.A. Akinduti3, O. Ejilude4, A. Oluwadun1

 

1. Department of Medical Microbiology and Parasitology, Olabisi Onabanjo University, Ago-Iwoye, Ogun State, Nigeria.

2. Department of Medical Laboratory Science, School of Public Health, Babcock University, Ilishan-Remo, Ogun State, Nigeria

3. Department of Veterinary Microbiology and Parasitology, University of Agriculture, Abeokuta, Ogun State, Nigeria.

4. Department of Microbiology and Parasitology, Sacred Heart Hospital,Lantoro Abeokuta, Ogun State, Nigeria.

5. Department of Microbiology, Olabisi Onabanjo University, Ago-Iwoye, Ogun State, Nigeria

 

ABSTRACT: Tapinanthus bangwensis is a parasitic plant with wide distribution and documented antimicrobial efficacies. Inconsistence in its activities has however, been suggestively linked with some factors. Hence, this study was carried out to establish the effect of some extrinsic factors on the antibacterial activities of T. bangwensis against some diarrhoeal causing bacteria. Antibacterial activity of T. bangwensis, collected from some parts of Nigeria was determined by standard agar-diffusion method. Results from this study showed a significantly higher zone of bacterial inhibition with chloroform extract when compared with ethanol and aqueous extracts (P<0.05). Higher antibacterial activities was also observed with extracts obtained from air dried plants than those obtained from sun dried and oven dried plants (P<0.05). Steaming method of extraction produced a significantly higher zone of bacterial inhibition than cold and hot methods of extraction (P<0.05). Percentage weight yield of active crude compound s of T. bangwensis was highest in chloroform (4.631.99%) than methanol (2.832.06%) and water (2.281.90%) (P<0.05). A significant positive correlation (r = +0.91, P<0.05) was observed between percentage weight yield and zone of antibacterial inhibition, exhibited by T. bangwensis. Weight yield accounted for 70% of antibacterial activities with a linear relationship of y = 3x + 5.6. Antibacterial activities of T. bangwensis were however, not affected by its host plants and varying concentrations of its crude extracts (P>0.05). Conclusion from this study has shown that solvents and methods of extraction such as mode of plant drying and means of concentrating extracts as important and influential extrinsic factors that determines the antibacterial activities of T. bangwensis.

[B.T. Thomas, H. I. Effedua, G.C. Agu, O.S. Musa, P.A. Akinduti, O. Ejilude, A. Oluwadun. Extrinsic Factors Influencing Antibacterial Activities of Tapinanthus bangwensis Against Diarrhoeal Causing Organsims. Academia Arena, 2012;4(2):1-4] (ISSN 1553-992X). http://www.sciencepub.net. 1

doi:

doi:10.7537/marsaaj040212.01

 

Keywords: Extrinsic Factor; Antibacterial; Tapinanthus bangwensis; Diarrhoeal; Organsims

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2

Study the Multipath Routing With Self-Healing Technique for Qos in MANET

 

R. K. Mishra *, Vimal Kumar **

 

* Dev Bhoomi group of institutions Dehradun

** Research Scholar, Teerthanker Mahaveer University Moradabad.

 

Abstract: In this paper we describe the multipath routing technique for mobile ad hoc networks. Because we know that Mobile equipments having very powerful and large memory, megabytes of disk space are becoming quite common today. And mobile technology is the best becoming technology for our life and generation. In this Network connectivity options for use with mobile hosts have increased also, including support for growing number of wireless networking product based on radio and infra-red. This type of mobile computing equipments has made the possibilities to share the information between mobile users. Mobile users will meet under circumstances that are not explicitly planned for and in which no connection to a standard network (Internet) is available. The solution to these types of networking problem has come up in the form of mobile ad hoc network. And in this paper we discuss the multipath routing with self healing technique for Qos in mobile ad hoc networks.

[R. K. Mishra, Vimal Kumar. Study the Multipath Routing With Self-Healing Technique for Qos in MANET. Academia Arena, 2012;4(2):5-7] (ISSN 1553-992X). http://www.sciencepub.net. 2

doi:10.7537/marsaaj040212.02

 

Keywords: : multipath routing technique; network;. large memory, mobile

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2

3

Investigation of The Laser Nano -Indentation Effects During Irradiation of AISI304 Stainless Steel

 

Hebatalrahman A(1), Rossetto Gilberto(2) and Carta Giovanni(2)

 

Consultant in materials sciences & materials applications, Egypt(1)

CNR-Institute of Inorganic chemistry and of Surfaces (ICIS), C. so Stati Uniti,4 35127 Padova Italy (2).

Hebatalrahman11@yahoo.com, hebatalrahman@naseej.com

 

Abstract: In this work, the surface of Austenitic Stainless steel AISI 304 was irradiated by Excimer laser 308nm at constant power 6mJ and repetition rate 200Hz. The selected alloy was irradiated at different number of pulses ranges from 2000 to 50000 Pulses. A significant change in the mechanical properties of AISI 304 is observed based on the microstructure changes. Laser surface irradiation process is a very complicated process and is found to be affected by the microstructure and chemical composition of the alloy. The mechanical properties such as Hardness and reduced modulus of the austenitic stainless steel 304 were improved. Hardness and modulus were decreased with both depth and load. The maximum improvement in nano-hardness and reduced modulus has been investigated in the surface of the sample and rapid decrease in the mechanical properties has been recorded along the depth. Both of quantitative and qualitative techniques were the main tools in results analyses.

[Hebatalrahman A, Rossetto Gilberto and Carta Giovanni. Investigation of The Laser Nano -Indentation Effects During Irradiation of AISI304 Stainless Steel. Academia Arena, 2012;4(2):8-15] (ISSN 1553-992X). http://www.sciencepub.net. 3

doi:10.7537/marsaaj040212.03

 

Keywords: Excimer Lasers, nano-measurements, Quantitative analysis, microstructure

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4

The Effect of Laser Parameters on The Surface Characteristic of Irradiated Stainless Steel 304

 

Hebatalrahman, A*

 

Consultant in materials sciences & materials applications, Egypt

hebatalrahman11@yahoo.com; hebatalrahman@naseej.com

 

Abstract: In these work, the effect of laser parameters such as wavelengths, number of pulses and energy per pulse were studied. The effect of number of pulses were studied in the range from 0 to 15000 at constant wavelength, the effect of energy per pulse was investigated at 3.5mJ and 6mJ. The commercial grade of polished stainless steel AISI 304 was considered as the base material in current study. Ultra violet excimer lasers at 193nm and 308nm were studied, Infra red lasers 1064nm was also tested. The superficial hardness and modulus were evaluated at different lasers parameters selected in these work to determine the optimum conditions. The total absorbed energy was calculated at all test conditions and compared with measured values. The optimum conditions to improve the mechanical properties at minimum energy were mentioned.

[Hebatalrahman, A. The Effect of Laser Parameters on The Surface Characteristic of Irradiated Stainless Steel 304. Academia Arena, 2012;4(2):16-24] (ISSN 1553-992X). http://www.sciencepub.net. 4

doi:10.7537/marsaaj040212.04

 

Keywords: Surface treatment, stainless steel alloys, Laser applications, mechanical properties

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5

Analytical Solution to Predict Transient Temperature Distributions during Laser Surface Hardening.

 

Hebatalrahman, A*

 

Consultant in materials sciences & materials applications, Egypt

hebatalrahman11@yahoo.com; hebatalrahman@naseej.com

 

Abstract: This paper introduces a new analytical solution to predict transient temperature distributions in a finite thickness plate during laser surface hardening. This analytical solution was obtained by solving a transient one-dimensional heat conduction equation with convection boundary conditions at the surfaces of the work piece. To calculate the temperature field analytically in laser surface hardening processes, laser beam absorptivity was evaluated as one of the most important parameters, the laser and materials parameres were determined. It was extremely difficult to find an accurate value for laser beam absorbtion rate. Therefore, in this paper, absorptivities were determined theoretically under various hardening conditions, including variations in hardened thickness beside variation in surface and subsurface temperature.Owing to the simplicity of the solution method, the analytical model developed may be easily implemented for simulation work for analysis and prediction of laser surface hardening processes under various hardening conditions.

[Hebatalrahman,A. Analytical Solution to Predict Transient Temperature Distributions during Laser Surface Hardening. Academia Arena, 2012;4(2):26-36] (ISSN 1553-992X). http://www.sciencepub.net. 5

doi:10.7537/marsaaj040212.05

 

Keywords: laser hardening, model, temeperature, energy distributiin. 

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6

Unsupervised CBIR by Combining Color, Shape (Features with a Threshold) and Lossless Gray Image Compression

 

Raj Kumar Mishra, Rajni Singh

 

DBGI, Dehradun, TMU, Moradabad; er.rajnisingh25@gmail.com

 

Abstract: Content-based image retrieval (CBIR) uses the visual features of an image such as color, shape and texture to represent and index the image. In a typical content based image retrieval system, a set of images sorted by similarities of their visual features with that of the query image are returned in response to a query. CLUE is a popular CBIR technique that retrieves images by clustering. In this paper, we propose a CBIR system that also retrieves images by clustering just like CLUE. But, the proposed system combines the color and shapes features with a threshold and lossless gray image compression for the purpose. The combination of the colored shape features and compression provides a robust feature set for image retrieval. We evaluated the performance of the proposed system using images from COREL database and compared its performance with that of the other two existing CBIR systems namely UFM and CLUE. Experimentally, we find that the proposed system outperforms the other two existing systems.

[Raj Kumar Mishra. Rajni Singh. Unsupervised CBIR by Combining Color, Shape (Features with a Threshold) and Lossless Gray Image Compression. Academia Arena, 2012;4(2):37-41] (ISSN 1553-992X). http://www.sciencepub.net. 6

doi:10.7537/marsaaj040212.06

 

Keywords: Content based image retrieval, image classification, unsupervised learning, spectral graph clustering, lossless gray image compression.

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7

HYDRATE MANAGEMENT STRATEGIES IN SUBSEA OIL AND GAS FLOWLINES AT SHUT- IN CONDITION

 

Usman, M.A. Olatunde, A.O, Adeosun T.A and Egwuenu, O.L.

 

Department of Chemical Engineering, University of Lagos, Nigeria

Department of Mathematics, Yaba College of Technology, Nigeria

abayomi200@yahoo.com, adebaba2001@yahoo.com

 

ABSTRACT: Flow assurance in deep-water developments has been identified as one of the main technological problems that the oil and gas industry faces today. Extreme conditions such as high pressures and low temperatures promote the formation of gas hydrates that can potentially reduce or completely block the flow path, causing severe financial losses. This work presents an integrated framework of model-based flow assurance management strategy to handling the effect of hydrates. The model-based flow assurance framework determines the operational limits of the production system to avoid the effect of hydrate plugs in the event of unplanned shut-in. P-T curve generated with a PVT sim software using Peng Robinson equation of state predicted the temperature – pressure operating envelop of the system. A Hot Oil return Temperature of 400C at the topside of the FPSO was determined with a suitably selected insulation material type and a minimum flow rate of 20,000bpd was determined. The analyses on how long the production system can sustain the available heat in the event of unplanned shut-in before a restart was done and a 10hr flowline cool down was achieved. A maximum of 3.5hrs of blowdown was also determined for the production system, which satisfies the analyses with three different water cuts- 0%, 50% and 70%. The framework is implemented in a state-of-the-art modelling tool (OLGA). The above analyses on these different scenarios are geared towards defining the operating limit of the subsea production facilities to preventing hydrate from forming during unplanned shut-in.

[Usman, M.A. Olatunde, A.O, Adeosun T.A and Egwuenu, O.L. HYDRATE MANAGEMENT STRATEGIES IN SUBSEA OIL AND GAS FLOWLINES AT SHUT- IN CONDITION. Academia Arena, 2012;4(2):42-54] (ISSN 1553-992X). http://www.sciencepub.net. 7

doi:10.7537/marsaaj040212.07

 

Key words: Flow Assurance,Hydrate, Peng Robinson, Hot Oil Return, Olga, Blowdown

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8

评吴耀琪先生的核育论

 

郑道

 

Recommended by Zhang Dongsheng

 

摘要21世纪科学的“中国弦”或“核弦”,才真正具有生命传承共性的内蕴;“核弦”从种子到繁育,表达了一种自然传承规律。

[郑道. 评吴耀琪先生的核育论. Academia Arena, 2012;4(2):55-61] (ISSN 1553-992X). http://www.sciencepub.net. 8

doi:10.7537/marsaaj040212.08

 

关键词核育论 中国弦 生存权 科学权

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9

一个备用的教案

 

谭天荣

 

青岛大学 物理系 青岛 266071

ttr359@126.com

 

Abstract: 按照我的意见,《自然辩证法》是一本没有定稿的书,其中的某些论点,对于一个没有自己重踏恩格斯的思路的读者是不可能理解的。这里我举一个例子,在该书的开头,恩格斯写道:力学,出发点的惯性,而惯性只是运动不灭的反面表现。”“惯性这一用语在这本书中只在这里惊鸿一瞥,以前不曾出现,以后也不再出现。这句话是什么意思,众说纷纭,迄今没有一个哪怕是字面上说得通的看法。爱因斯坦是诚然一个卓越的物理学家,但他肯定不知道恩格斯这里说的是什么意思。

[谭天荣. 一个备用的教案. Academia Arena, 2012;4(2):62-63] (ISSN 1553-992X). http://www.sciencepub.net. 9

doi:10.7537/marsaaj040212.09

 

Keywords: 力学; 惯性; 物理学; 数学; 《自然辩证法》

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The articles in this issue are presented as online first for peer-review starting from 1/26/2012. 
All comments are welcome: editor@sciencepub.net

For back issues of the Academia Arena, click here.

Emails: editor@sciencepub.net; sciencepub@gmail.com
Website: http://www.sciencepub.net/academia

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doi:

doi:10.7537/marsaaj040212.01

doi:10.7537/marsaaj040212.02

doi:10.7537/marsaaj040212.03

doi:10.7537/marsaaj040212.04

doi:10.7537/marsaaj040212.05

doi:10.7537/marsaaj040212.06

doi:10.7537/marsaaj040212.07

doi:10.7537/marsaaj040212.08

doi:10.7537/marsaaj040212.09

 

 

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