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Item Nutritional quality of Cavendish banana (Musa acuminata, AAA) as affected by basil oil and determination of basil oil residues by GC-MS(Journal of Science, Faculty of Science, University of Kelaniya, 2019) Siriwardana, H.; Abeywickrama, K.; Kannangara, S.; Jayawardena, B.The effectiveness of basil oil on the nutritional properties of Cavendish banana and chemical composition of basil oil and oil residue levels of treated banana fruits were evaluated in this study. Cavendish banana hands were treated with 1% alum (w/v), 1% alum (w/v) + 0.4% Ocimum basilicum (basil) oil, distilled water (control) and packaged in Low Density Polyethylene (LDPE) bags and stored at a cold room at 12-14ºC. After two weeks of cold storage banana were induced ripened and nutritional contents of treated Cavendish banana were determined. Gas Chromatography - Mass Spectrometry (GC-MS) was instrumental in identifying the chemical constituents of basil oil as well as residues in basil oil treated Cavendish banana peel after two weeks of storage at 12-14ºC.Item Postharvest Application of Defence Elicitors to Managae Anthracnose In Mango Fruit(Journal of Science, Faculty of Science, University of Kelaniya, 2019) Karunanayake, K.O.L.C.The use of defense elicitors; which are agents that stimulate or trigger disease resistance responses in plants have proved to be attractive alternatives to hazardous chemical fungicides in recent years. The present study investigated the possibility of using Salicylic acid and Bion® as postharvest elicitors on mango fruit. Three local mango cultivars were used in the study, ‘Karuthacolomban’, ‘Rata’ and ‘Willard’. Salicylic acid was applied as a postharvest spray at concentrations, 100, 500 or 1000 mg/L and Bion® (Acibenzolar-s-methyl, 500 WG, SYNGENTA) at 25, 50, 100 and 200 mg/L. Disease development following artificial inoculation (10 5 conidia / ml suspension) was assessed. Both elicitors were effective (P<0.05) in controlling postharvest anthracnose. The most effective concentration of SA was 500 mg/L for ‘Rata’, 100 mg/ L for ‘Willard’ and both 100 and 500 mg/L for ‘Karuthacolomban’. In Bion® the most effective concentration was 50 ppm for ‘Rata’ and ‘Willard’ and 25 ppm for ‘Karuthacolomban’. In SA treated fruits the percentage reduction in anthracnose ranged from 40- 77 % while values ranged from 67 – 99% for Bion® treated fruits. Results indicate that both SA and Bion® can be used to control postharvest mango fruit loss due to anthracnose.Item Geographic Records of Subfamilies, Genera and Species of Ants (Hymenoptera: Formicidae) In The Four Climatic Zones of Sri Lanka: A Review(University of Kelaniya, 2016) Dias, R.K.S.; Rajapaksa, R.P.K.C.Ants are a major biotic component in the terrestrial environment of Sri Lanka. For the first time, geographic records of worker ants from the surveys conducted in the four climatic zones of Sri Lanka from 1999 to 2016 have been summarized. Geographic records of subfamilies, genera and 95 species of ants from variety of localities in each climatic zone were pooled and tabulated for each taxon. Among the 11 subfamilies, Amblyoponinae, Dolichoderinae, Formicinae, Myrmicinae, Ponerinae and Pseudomyrmecinae were common to the lands in the four zones while each of the other subfamilies were recorded from a single zone or two or three zones only. The Sri Lankan Relict Ant in Aneuretinae has many records in the wet zone and two records in the intermediate zone. Twenty two among 64 ant genera were recorded from the four climatic zones; 42 genera were found in a single zone or two or three zones. Recorded occurrence of each of the 95 species showed that 24 including 8 invasive species, Anoplolepis gracilipes, Monomorium pharaonis, Paratrechina longicornis, Solenopsis geminata, Tapinoma melanocephalum, Technomyrmex albipes, Tetramorium bicarinatum and Trichomyrmex destructor were common to the four zones. Further surveys on ants of Sri Lanka are highly recommended for improving the current knowledge on their occurrence and to provide information on the distribution of endemic and invasive ant species in Sri Lanka.Item Five Layered FCC Ferromagnetic Films as Described by Modified Second Order Perturbed Heisenberg Hamiltonian(University of Kelaniya, 2016) Samarasekara, P.; Warnakulasooriya, B.I.For the first time, the 2nd order perturbed Heisenberg Hamiltonian with all the seven magnetic energy parameters was solved for fcc structured ferromagnetic films with five layers. Previously, the 2nd order perturbed Heisenberg Hamiltonian was solved for four layered ferromagnetic films under some special assumptions by us. However, the exact solution of 2nd order perturbed Heisenberg Hamiltonian without any special assumption is formulated in this manuscript. The magnetic easy and hard directions were determined using the angles corresponding to the energy minimum and maximum in the 3-D and 2-D plots. The shape of the 3-D plots doesn’t change with the number of layers except the position of spikes. However, the magnetic easy direction varies with the number of layers. Most of the theoretical data obtained by our model agree with the experimental data of ferromagnetic thin films.Item Species richness of arboreal ant assemblages (Hymenoptera, Formicidae) and frequency of Oecophylla smaragdina (Fabricius) occurrence in a wet zone cashew (Anacardium occidentale L.) field in Sri Lanka(University of Kelaniya, 2016) Dias, R.K.S.; Perera, A.P.S.Ant assemblages on cashew trees in the wet zone of Sri Lanka were recorded throughout three phenological phases from March to June in 2015. Baited trapping and hand collection recorded fourteen ant species in five subfamilies and species richness observed on each occasion ranged from 7 to 11. Absence of serious cashew pests was noticeable in the current phenological cycle. Oecophylla smaragdina (Fabricius) was the only species recorded on all trees. Number of O. smaragdina nests observed on the same cashew trees in the two plots was recorded from April to June in 2015 and nests of the species were observed only on large and medium-sized trees. The materials carried by O. smaragdina workers on cashew tree branches were also collected, preserved in 70% ethanol and identified as far as possible using a Low Power Stereo-microscope and various plant and animal materials carried by workers confirmed that the species is an omnivore and a generalist predator. In the current study absence of serious damages caused by the cashew insect pests even without any insecticide application might be due to the presence of ant assemblages on cashew trees.Item Optical and Structural Properties of Spin Coated Cadmium Sulfide Thin Films(University of Kelaniya, 2015) Dissanayake, D.M.C.U.; Samarasekara, P.Thin films of cadmium sulfide have been synthesized using the spin coating technique. Films were fabricated on inexpensive amorphous glass substrates at spin speeds of 1500, 2200 and 2400 rpm for 30 seconds. Films were subsequently annealed at 200, 300 and 400 0C for one hour in air in order to crystallize the phase of CdS. Films were characterized using X-ray diffraction patterns (XRD) and UV-visible spectroscopy. According to XRD patterns, the phase of CdS was crystallized without any secondary phases. The particle size, dislocation density and strain were also estimated using XRD patterns. All the films indicate a strong orientation in (002) direction. The optical band gap was determined using UV absorption spectroscopy. Tauc model was employed to determine the optical band gap. According to our data, the optical band gap decreases with the particle size.Item An Exact Solution of Non-Newtonian Peristaltic Flow in a Tube : Rabinowitsch Fluid Model(University of Kelaniya, 2015) Singh, U.P.With the development of medical science, non-Newtonian fluids have taken on added significance with a variety of applications in real life. The flow of non-Newtonian fluids in tubes and pipes plays a vital role in daily life. The examples of such applications are medical instruments, human body, machines, etc. The study of such mechanisms with the Newtonian fluids has not been found satisfactory due to nonlinear behavior of stress strain relationship. In the present analysis, the study of peristaltic flow in a tube has been carried out taking into account the non-Newtonian fluid : Rabinowitsch fluid model. Considering the significant terms in Navier-Stokes equations, solutions have been derived for fluid flow in axial direction in terms of pressure gradient. Using the continuity of flow, and exact solution has been derived for fluid pressure at wall. To establish the applicability of the solution, results for pressure rise at wall, pressure gradient and streamlines have been presented graphically.Item Lesson 32: Generation of biogas from degradable organic wastes(Research Services Centre, Faculty of Science, University of Kelaniya, 2015) Yatawara, M.D.M.D.W.M.M.K.Item Lesson 31: Isolation of Clove Oil by Steam Distillation(Research Services Centre, Faculty of Science, University of Kelaniya, 2015) Arachchige, N.M.Item Lesson 30: Identification and culture of ornamental aquatic plants(Research Services Centre, Faculty of Science, University of Kelaniya, 2015) Epa, U.P.K.