iPURSE 2019
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- ItemDeveloping a non host-specific biofertilizer: a microbial biofilm approach(University of Peradeniya, Sri Lanka, 2019-09-12) Singhalage, I. D.; Seneviratne, G.; Madawala, H. M. S. P.Host specificity of biofertilizers may pose several issues at large scale production and usage. The present study examined the universality of a fungal-bacterial biofilmed biofertilizer (BFBF) in comparison to its monoculture bacterial (BBF) and fungal (FBF) biofertilizers using three crops, Strawberry, Tomato and Rice. The BFBFs were formulated using strawberry (Fragaria ananassa) rhizosphere-associated bacterial (Enterobactor sp.) and fungal (Aspergillus sp.) strains. Strawberry, rice and tomato were grown in hydroponic medium with liquid biofertilizers (BFBF, BBF and FBF) applied at same ratio of biofertilizer: hydroponic medium in 1:9 ratio (in volume). A control was maintained in the hydroponic medium but without biofertilizers. The treatments were triplicated and arranged in a completely randomized design. The growth medium collected at different time intervals were analyzed for polysaccharides, amides and lipids by Fourier Transform Infra-red spectroscopy. Plant height and dry mass were recorded after a month. Data were analyzed by ANOVA and correlation. After 30 days, all crops showed significantly improved concentrations of polysaccharides, amides and fatty acids in media treated with BFBF, BBF and FBF over the control. The dry biomass and heights of strawberry and rice plants were significantly (p<0.05) higher in BFBF over the BBF, FBF and the control. In tomato, BFBF-treated seedlings also showed better growth, though not significantly. Concentrations of functional polysaccharides (14ᵗʰand 30ᵗʰdays), fatty acids (7ᵗʰand 14ᵗʰdays) and amides (30ᵗʰday) were positively and significantly correlated with the growth of strawberry plant. The growth of rice also showed a significant positive correlation with functional polysaccharides (14ᵗʰ day), fatty acids and amides (30ᵗʰday). In tomatoes, a significantly positive correlation was noted with the functional polysaccharides, fatty acids and amides after 30 days. The findings suggest that the BFBF developed from strawberry root-associated microbes nullify the general concept of crop specificity by potentially improving the growth of rice and tomato. As such, the BFBF seems to have a higher ability to improve the growth of crops in comparison to conventional monoculture biofertilizers.
- ItemEvaluation of Ground source cooling potential for Batticaloa, Sri Lanka(University of Peradeniya, Sri Lanka, 2019-09-12) Suganya, E.; Ariyawansha, R. T. K.; Ganepitiya, G. G. S. M.; Basnayake, B. F. A.Ground source for cooling has been identified as a promising technology in dry tropical regions. However, it is not popular in Sri Lanka. Therefore, this study was conducted to design a ground source cooling system that can be adopted in Batticaloa, Sri Lanka (Dry zone). The experiment was conducted during July and August, the hottest period of the year for Batticaloa. Thermocouples fixed to a data logger were installed into the soil to obtain the temperature profiles up to 7 m. It was found that the temperature did not vary below 2 m from the surface. The temperature at the water table depth of 7 m was 27 0C. In utilizing this information, the cooling load for a system was designed for a 3 m×3 m×3 m room with the occupation of four people and some electrical equipment. The calculations were based on thermal conductivity determined from experimental and standard values from literature. The highest ambient room temperature was considered as 40 ⁰C. Total cooling load approached a value of 5.2 kW to reduce and maintain the room temperature at 27 ⁰C. Water was used in the calculation as the heat-transfer medium of the system. It requires a flow rate of 2.48 × 10⁻⁴ m³/s with a pump rating of 24.33 W to maintain the required cooling load. It can be obtained from solar power. The copper tube selected for the design of heat exchanger has the dimensions of 0.9 cm inner and 1.14 cm outer diameters and best installed down to 7 m. Flat horizontal tubes are preferred to increase the contact surface area with soil and water filled pores. The application of Arduino-uno could increase the efficiency of the system by optimizing operating conditions. Coupling with pre-existing refrigeration system can boost the efficiency and demand where, we can have varying temperature according to the comfort preferences.
- ItemProcessing of aromatic rice using 2-acetyle-1-pyrroline available in pandan (Pandanus amaryllifolius Roxb) leaves(University of Peradeniya, Sri Lanka, 2019-09-12) Mayadunna, H. R. D. M.; Dharmasena, D. A. N.Aromatic rice has a high demand and a premium price in the global market. The aromatic volatile chemical compound, 2-acetyl-1-pyrroline (2-AP) is, mainly responsible for the characteristic fragrance in aromatic rice. The aromatic essence 2-AP is found in Pandan leaves (Pandanus amaryllifolius Roxb) that are grown in tropical countries and commonly available in Sri Lanka. Fresh Pandan leaf has 10 times higher 2-AP than Basmati rice which contains around 1 ppm of 2-AP. This study was investigated the feasibility of transferring 2-AP available in Pandan leaves to non-aromatic short grain raw rice (BG- 360) for value addition. In order to increase the rice grain porosity to facilitate absorption of aroma, rice grains (BG-360) were vacuum dried (without soaking) to about 5% moisture at 70 ⁰C. 2-AP absorption was tested as direct leaf heating after mixing leaf with rice by microwave oven in a sealed chamber and using the ethanol extract of the chemical (2-AP). The microwaved treated rice samples were kept for three weeks for 2-AP absorption at room temperature. The ethanol extract treatment was tested for optimum absorption time to rice. Finally, raw rice, rice subjected to direct heating with leaf and treated with 2-AP extract were compared with premium quality Daawat Rozana Basmathi Rice by examining fragrance characteristics of treated raw and cooked rice using sensory panel. The results revealed that the best treatment for transferring 2-AP from leaf to raw rice is direct microwave heating of vacuum dried raw rice mixed with fresh Pandan leaves at a mass ratio of (leaves : rice) 1:10.
- ItemA review: fractionation methods of starch components (Amylose and Amylopectin) for industrial applications(University of Peradeniya, Sri Lanka, 2019-09-12) Amaraweera, A. P. S. M.; Manipura, W. M. J. A. S. B.; Manamperi, W. A.; Gunathilake, C. A.Starch is a natural polymer that can be used in industrial applications to prepare biodegradable artifacts. But these have many drawbacks such as high water absorption, low mechanical strength, and lesser durability. Properties of starch (chemical and physical) and that of the resultant applications are much dependent on the amylose to amylopectin ratio. Recent research studies have focused on fractionation of starch components and modifying the compositions of amylose and amylopectin for specific applications. Formulation of polymer blends with starch and various additives (cross linkers, plasticizers etc.) have led to significant improvements of properties in industrial applications such as plastics and composite material. This review mainly focuses on the recent developments in fractionation of starch using chemical, physical, and enzymatic methods. Of these, the physical and chemical fractionation methods are widely used, whereas enzymatic methods are used for highly specific applications. The main challenges of starch fractionation include high solubility and susceptibility to structural degradation. Recent studies have made significant progress in investigating various solvent mixtures and other process variables in order to overcome these challenges.
- ItemMigration framework for traditional web applications into CMS platform(University of Peradeniya, Sri Lanka, 2019-09-12) Jayathilaka, G. A. S. C.; Arachchige, J. A.Most of the organizations all over the world use web based information systems to operate their day-to-day activities. Due to the rapid changes of the organizational needs, the content inside these web applications are also increased agilely. Maintaining the increasing content while keeping consistency of the information is a challenging task. Content Management Systems (CMS) provide a platform to author the web information by different users of the system while maintaining the uniformity of the content. Therefore nowadays most of the web applications are moving to CMSs because of its easiness in developing and maintaining web systems. Starting the web development from the scratch in CSM platform requires immense effort for requirement gathering and information finding. Therefore migration of traditional web applications to CMS platform has been paid considerable attention. However very few researches focus on this migration process. The main objective of this research is providing a framework for migrating traditional web applications to CMS platform. The proposed framework provides a guided path for existing web applications to move into CMS. The framework is defined based on CMS Common Meta-Model which was proposed by V. de Castro et.al. in their research. A software tool was developed using Python, Java and Jython to automate the migration process. In the analysis of CMS Common Meta-Model few drawbacks were identified. Therefore the meta-model was extended to include dynamic ability of a web page. The results were validated with selected web sites with different technologies. The proposed framework provides an efficient way to compile web applications in CMS platform with web content of the traditional web site.