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Sunday 4 December 2016

Study of the Effects and Interaction of Operational Parameters on the Fabrication of Silver Nanoparticles (AgNPs)-Loaded Chitosan-Polylactic Acid-Based Films Using Full Factorial Design

Published Date
Date: 

Author 
  • S. Aznizan 
  • M. N. Abu Seman
  • C. K. M. Faizal

Abstract

Fabrication of silver nanoparticles-loaded chitosan-polylactic acid-based films was successfully employed for investigating the effect and interaction factors that affect the tensile strength and elongation at break responses. The two factors were the concentration of polyethylene glycol (PEG) 400 and the ratio of polylactic acid (PLA)/chitosan. Analysis of results was performed by using two-level full factorial design (FFD) to avoid the traditional one-factor-at-a-time experiments, and the model constructed by FFD resulted in improved response, reduced process variability, and closer confirmation of response to targeted requirements. Common statistical tools such as analysis of variance (ANOVA), Pareto chart, normal probability plot of the residuals, and main effect plot with its response were used to determine the most important process variables affecting tensile strength and elongation at break responses. The use of FFD allowed for identification of the most significant parameters under tested conditions. From the results of statistical analysis, it could be concluded that both the concentration of polyethylene glycol (PEG) 400 and the ratio of polylactic acid (PLA)/chitosan had significant effect on tensile strength and elongation at break responses. Therefore, the concentration of polyethylene glycol (PEG) 400 and the ratio of polylactic acid (PLA)/chitosan content in the blend films were employed for a surface analysis design in order to achieve an optimal quality of film based on tensile strength and elongation at break responses. From Table 90.1, the standard order 15 (A = 15 %, B = 50/50) showed the best results in tensile strength and elongation at break which are 8.27376 Mpa and 23.4974 %, respectively. The results from FFD could be studied further expanded to a central composite design, in order to fit the measured data to a quadratic model and to calculate response surfaces.

References

  1. 1.
    Lagaron, J. M., & Lopez-Rubio, A. (2011). Nanotechnology for bioplastics: Opportunities, challenges and strategies. Trends in Food Science & Technology, 22(11), 611–617.CrossRef
  2. 2.
    Wei, D., Sun, W., Qian, W., Ye, Y., & Ma, X. (2009). The synthesis of chitosan-based silver nanoparticles and their antibacterial activity. Carbohydrate Research, 344(17), 2375–2382.CrossRef
  3. 3.
    Shaari, A., Seman, M. N. A., & Ku, C. K. M. F. C. (2012). Silver nanoparticles (AgNPs)-loaded chitosan-polylactic acid (PLA) based films: Fabrication and antimicrobial properties. Proceedings of International Conference on Chemical and Biochemical Engineering, Kuala Lumpur, 3–5 Dec 2012.
  4. 4.
    Ste, G., Copinet, A., & Coma, V. (2006). Novel biodegradable films made from chitosan and poly (lactic acid) with antifungal properties against mycotoxinogen strains. Chemical Engineering Journal, 65, 185–193.
  5. 5.
    Mayer, J. W. V. A., Bailey, S. J., Baldini, N. C., Emery, S., Ermigiotti, J., Huffman, B., Olcese, M. A., Peters, K. A., Rosiak, J. L., Terruso, D. A., & Whealen, E. A. (2007). ASTM packaging standards and related technical material(7th ed.). West Conshohocken: ASTM International.
  6. 6.
    Gottipati, R., & Mishra, S. (2010). Process optimization of adsorption of Cr(VI) on activated carbons prepared from plant precursors by a two-level full factorial design. Chemical Engineering Journal, 160(1), 99–107.CrossRef
  7. 7.
    Bhavsar, M. D., Tiwari, S. B., & Amiji, M. M. (2006). Formulation optimization for the nanoparticles-in-microsphere hybrid oral delivery system using factorial design. Journal of Controlled Release: Official Journal of the Controlled Release Society, 110(2), 422–430.CrossRef
  8. 8.
    Fangueiro, J. F., Andreani, T., Egea, M. A., Garcia, M. L., Souto, S. B., & Souto, E. B. (2012). Colloids and surfaces B: Biointerfaces experimental factorial design applied to mucoadhesive lipid nanoparticles via multiple emulsion process. Colloids and Surfaces B: Biointerfaces, 100, 84–89.CrossRef
  9. 9.
    Pongstabodee, S., Monyanon, S., & Luengnaruemitchai, A. (2012). Applying a face-centered central composite design to optimize the preferential CO oxidation over a PtAu/CeO2–ZnO catalyst. International Journal of Hydrogen Energy, 37(6), 4749–4761.CrossRef
  10. 10.
    Alqadi, A. N. S., Mustapha, K. N. B., Naganathan, S., & Al-Kadi, Q. N. S. (2012). Development of self-compacting concrete using contrast constant factorial design. Journal of King Saud University – Engineering Sciences, 3(1), 201–205.

For further details log on website :
http://link.springer.com/chapter/10.1007/978-981-287-077-3_90

Impact of Applying Radiant Barrier Fitted Beneath the Roof in Hot and Humid Climates

Published Date
Date: 

  • S. B. Azraai 
  • M. I. Ali
  • S. S. Salleh
  • O. Asaroon
Abstract 

In tropical climates, about 70 % of heat transfer is through the roof into room spaces. Heat gained in the house comes from solar radiation, lighting, heating and electrical appliances. The room temperature in the house is greater than the outside temperature due to heat gain during hot day. In hot day, room temperature in a house is ranging from 29 to 33 °C. The occupants feel discomfort to stay in the house especially at night. Linked houses in Malaysia are known to be very uncomfortable for living without forced ventilation and cooling. The dwellers have to use air conditioners to overcome uncomfortable condition. The usage of air conditioning will increase the electrical energy. The staggered air-bubble packed aluminium foil as radiant barrier has been chosen to reduce the heat transfer through the roof. The aluminium foil is fitted beneath the roof. The experiment has been conducted in the test cell in determining the temperature profiles using eight temperature sensor data logger interfaced with personal computer. Result shows that the average indoor air temperature is reduced by 0.7 °C. Electrical energy consumption in residential building is reduced using reflective aluminium foil.

References 

  1. 1.
    Suman, B. M., & Srivastava, R. K. (2009). Influence of thermal insulation on conductive heat transfer through ceiling construction. Journal of Scientific & Industrial Research, 68, 248–251.
  2. 2.
    Michels, C., et al. (2008). Theoretical and experimental comparison of heat flux reduction in roofs achieved through the use of reflective thermal insulators. International Journal of Energy and Building, 40, 438–444.CrossRef
  3. 3.
    Abraham, J., & George, C. (2007). Full building radiation shielding for climate control in desert regions. International Journal of Sustainable Energy, 26(3), 167–177.CrossRef
  4. 4.
    Devulder, T., Wilson, R., & Chilton, J. (2007). The thermal behaviour of buildings incorporating single skin tensile membrane structures. International Journal of Low Carbon Technologies, 2(2), 195–213.CrossRef
  5. 5.
    Yoshiro, H., Hasegawa, K., & Matsumoto, S. (2005, May) Passive cooling effect of building features in traditional Japanese buildings. International conference passive and low energy cooling for built environment, Santorini, pp. 573–578.

For further details log on website :
http://link.springer.com/chapter/10.1007/978-981-287-077-3_89

Problems on Commercialisation of Genetically Modified Crops in Malaysia

Published Date
Date: 

Author 
  • Tengku Norbaya Binti Tengku Azhar 
  • Kamariah Binti Ismail

Abstract

Since the 1980s, Malaysia has enthusiastically worked on the development of genetically modified (GM) crops. However, with certain barriers and hindrance, the successful development seems unattainable. This paper explores the critical factors and issues which affect the successful commercialisation of GM crops in Malaysia. Six major factors such as the human capital and other capital requirement, biosafety regulation, institutional roles, intellectual property (IP) protection, technical constraints and public acceptance were investigated using face-to-face and telephone interview which involved ten respondents from several institutions. The data was analysed using NVivo computer software version 2.0. According to the results of the research, the most crucial factors were human capital, other capital requirement and institutional roles. A combination model was constructed using the dimension of the six factors and the development model of agro-based product by Monsanto.

References 

  1. 1.
    Brooker, R. J. (2005). Genetics analysis and principles (2nd ed.). New York: McGraw-Hill companies, Inc.
  2. 2.
    Ellis, G. C. (2006). Report on the status of agricultural biotechnology, R&D and intellectual property in Malaysia and Thailand 2006. CIPP&PIPRA Rep. 36pp.
  3. 3.
    Taylor, N., Kent, L., & Fauquet, C. (2004). Progress and challenges for the deployment of transgenic technologies in cassava. AgBioforum, 7(1&2), 51–56.
  4. 4.
    Ozor, N. (2008). Challenges and impacts of agricultural biotechnology on developing societies. African Journal of Biotechnology, 7(4), 322–330.
  5. 5.
    Idris, S. H. (2008). Bio safety law: Does it really protect the environment? International conference on environmental research and technology (ICERT) 2008, Penang, pp. 297–302.
  6. 6.
    Kalaitzandonakes, N., Alston, J., & Bradford, K. (2007). Measuring the costs of biosafety regulation and the potential impacts on biotechnology research and development. 9th internal symposium on the biosafety of genetically modified organisms, Jeju Island, 24–29 Sept 2006, pp. 173–178.
  7. 7.
    Zhong, F., Marchant, M. A., Ding, Y., & Lu, K. (2002). GM foods: Nanjing case study of Chinese consumers’ awareness and potential attitudes. AgBioforum, 5(4), 136–144.
  8. 8.
    Wen, Y. K (2006). The road to commercialization of transgenic products in Taiwan-A bridge too far. International symposium on ecological and environmental of biosafety of transgenic plants, Syngenta, pp. 193–210.
  9. 9.
    Abu Bakar, U. K. (2007). Commercialization of biotech crop in Asia course: Benefits to MARDI and Malaysia. High level policy dialogue on agriculture biotechnology, Canberra, 20–21 Jan 2007, pp. 1–8.
  10. 10.
    Monsanto. (2009). Understand the pipeline. Retrieved Aug 30, 2009, from http://​www.​monsanto.​com/​

For further details log on website :
http://link.springer.com/chapter/10.1007/978-981-287-077-3_86

Potential Identification of Compacted Soil as Alternative Material in Cold-Formed Steel Column

Published Date
Date: 

Author 
  • Mohd Mawardi Bin Mohd Kamal 
  • Mohd Syahrul Hisyam Bin Mohd Sani
  • Fadhluhartini Binti Haji Muftah

Abstract

Soil is a complex material composed essentially of clay minerals and sand with organic and associated minerals which influence soil properties. The purpose of this study is to identify the potential of compacted soil as an alternative material in construction by replacing concrete for retaining walls or foundation structure. The materials that have been used in this study were categorized as the main groups of crystalline materials of clay that is called kaolinite. The specific gravity test result showed 2.6 Gs, which categorizes the soil into the kaolinite group. Besides, this material improved the soil characteristics by compaction with the optimum moisture content using the standard Proctor test. The result from the standard Proctor test is determined by the ratio of soil mass to the maximum water content in the soil, with the achieved ratio being 5.5 kg of soil to :920 ml of water in this case. The result from the unconfined compressive strength test was 78 kN/m2, which shows medium consistency of kaolinite, thus showing a good prospective for it to replace concrete in columns. In addition, the material is also compared with residual soil as another alternative for contact with cold-formed steel sections. The different values of specific gravity and unconfined compressive strength are recorded as 0.11 and 226 kN/m2, respectively. It also illustrated that kaolinite has a potential for contact with or to fill in cold-formed steel columns.

References 

  1. 1.
    Muni Budhu. (2007). Soil mechanics and foundations. (2nd ed.). Department of Civil Engineering & Engineering Mechanics, University of Arizona.
  2. 2.
    BS1377-7. (1990). Methods of test for soils for civil engineering purposes. Shear strength tests (total stress). University of New York.
  3. 3.
    Das, B. M. (2006). Principles of geotechnical engineering. Sacramento: California State University.
  1. 4.
    Gumaste, K. S., Rao, K. S. N., Reddy, B. V. V., & Jagadish, K. S. (2007). Strength elasticity of brick masonry prisms and wallettes under compression. Materials and Structures, 40(2), 241–253.CrossRef
  2. 5.
    Hall, M., & Allinson, D. (2008). Assessing the moisture-content-dependent parameters of stabilized earth materials using the cyclic-response admittance method. Energy and Buildings, 15, 5–3.
  3. 6.
    Bui, Q.B., Morel, J.C., Hans, S., Meunier, N. (2008). Compression behaviour of nonindustrial materials in civil engineering by three scale experiments: The case of rammed earth. Materials and Structures, 11, 7–10.
  4. 7.
    Azeredo, G., Morel, J. C., & Lamarque, C. H. (2008). Applicability of rheometers to characterizing earth mortar behavior. Part I: Experimental device and validation. Materials and Structures, 41, 1465–1472.CrossRef

For further details log on website :
http://link.springer.com/chapter/10.1007/978-981-287-077-3_87

Fabrication and Characterization of Porous and Nonporous Y3CaBa4Cu8OδSuperconductor

Published Date
Date: 

  • Author 
  • S. A. Syamsyir 
  • H. Azhan
  • Z. A. S. Zuliana
  • W. A. W. Razali
  • A. W. Norazidah
  • H. N. Hidayah
  • J. S. Hawa
  • H. J. M. Ridzwan
  • A. Nazree

  • Abstract

    These pioneer studies unveil the distinguishable properties of standard YBa2Cu3O7 (Y123) and Y3CaBa4Cu8Oy (Y348) in terms of its porous and nonporous structure. Solid-state reaction method was used to fabricate the ceramic materials which involve a series of heating and grinding. The electrical properties of superconductor such as critical temperature, T c, and critical current density, J c, were determined using resistivity measurement system (RMS). Scanning electron microscope was used to analyze the structural properties and morphology of particular material, respectively. The highest critical current density (J C) is porous (Y123) which is 2.66 A/cm2 instead of 2.34 A/cm2for porous Y3CaBa4Cu8Oy. The critical temperature YCaBa2Cu3Oy (Y123) for porous structure is much higher compared to nonporous structure, which is T C = 89 K. The critical temperature for porous YCaBa4Cu6Oy is 65 K which is higher than the nonporous sample. SEM micrograph for porous structure showed the increase of critical currents is dominantly determined by porosity due to bigger and continuity formation of grains which lessen the current blocking effect causes by grain boundaries.

    References 

    1. 1.
      Ali Yusuf, A., Yahya, A. K., Nawazish, A. K., Salleh, F. Md., Marsom, E., & Huda, N. (2011). Effect of Ge4+ and Mg2+ doping on superconductivity, fluctuation induced conductivity and interplanar coupling of TlSr2CaCu2O7_d superconductors. Physica C, 471, 363–372.CrossRef
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      Mohan, R., Singh, K., Kaur, N., Bhattacharya, S., Manglesh Dixit, N. K., Gaur, V. S., Gupta, S. K., & Singh, R. K. (2007). Calcium and oxygen doping in YBa2Cu3Oy. Solid State Communications, 141, 605–609.CrossRef
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      Hari Babu, N., Kambara, M., McCrone, J., Cooper, J. R., Tallon, J. L., & Cardwell, D. A. (2001). Fabrication of Ca-doped large grain Y-Ba-Cu-O superconductors. IEEE Transactions on Applied Superconductivity, 11(1), 3521.CrossRef
    4. 4.
      Bandyopadhyay, S. K., Pintu, S., Barat, P., Mukherjee, P., Bhattacharyay, A., Rajasekar, P., Chakraborty, P., Caccavale, F., LoRusso, S., Ghosh, A. K., & Basu, A. N. (1997). A study of superconducting (Y1−x) Ba2Cu3OyPhysics Letters A, 226(3–4), 237–243.CrossRef
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      Rajiv, G., Awana, V. P. S., Singh, H. K., Tiwari, R. S., Srivastava, O. N., Anurag, G., Kumaraswamy, B. V., & Kishan, H. (2005). Effect of Ca doping for Y on structural/microstructure and superconducting properties of YBa2Cu3O7−δPhysica C: Superconductivity, 419(3–4), 101–108.
    6. 6.
      Shlyk, L., Krabbes, G., Fuchs, G., & Nenkov, K. (2002). Melt-processed YBCO doped with Ca and Cd: Comparison of superconducting properties. Physica C, 383, 175–182.CrossRef
    7. 7.
      Rutter, N.A., Durrell, J.H., Mennema, S.H., Blamire, M.G., MacManus-Driscoll J.L. (2005). Transport properties of Ca-doped YBCO coated conductors. IEEE Transactions On Applied Superconductivity15(2).
    8. 8.
      Davelos Bagarinao, K., & Yamasaki H. (2008) Large area pulsed laser deposition of YBaCu3O7-d thin film: Microstructure and flux pinning properties, YBCO superconductors progress report, (pp. 53–92). Nova Science Publisher.
    9. 9.
      Shaaidi, W. N. A. W., Mansor, M. K., Lim, K. P., Matori, K. A., Saion, E., Halim, S. A., & Chen, S. K. (2011). Influence of Ca doping on the superconductivity of Y1−xCaxBa2Cu3O7−δSolid State Science & Technology: Superconductivity, 19(2), 242–248.

    For further details log on website. :
    http://link.springer.com/chapter/10.1007/978-981-287-077-3_79

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