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Item Comparative Pharmacognostic Aspects of Rauvolfia Serpentina (L.) Benth. Ex Kurz and it's Substitute Rauvolfia Canescens L. (Apocynaceae)(Uva Wellassa University of Sri Lanka, 2014) Savithri, W.A.K.Rauvolfia serpentina (L.) Benth. ex Kurz (Apocynaceae), a rare, therapeutically important medicinal plant, is often adulterated by materials of Rauvolfia canescens L. (Apocynaceae). However, adulteration of R. serpentina with R. canescens without scientifically proven data on important quality standards might adversely affect the therapeutic properties of the herbal drugs. Therefore, the present study was undertaken to establish a comparative quality standards on morphological, anatomical, phytochemical, physicochemical and cytotoxicity activity of R. serpentina and R. canescens by using established protocols. Results demonstrated that R. serpentina could be distinguished from R. canescens by comparing polymorphological characters and anatomical characters. Major phytochemical groups were present in leaves, stems and roots of both plants. Results of Thin Layer Chromatogram (TLC) exhibited the highest number of common spots in leaf extracts followed by stem and root extracts of both R. serpentina and R. canescens. The presences of higher brine shrimp toxicity in root extracts of both plant species scientifically validate the use of root in medicinal purposes in Ayurveda and traditional systems of medicine in Sri Lanka. Information generated through the present study could be effectively used for the quality control and standardization process of different parts of Rauvolfia serpentina and Rauvolfia canescens in order to upgrade the Sri Lankan pharmacopeia. The presence of certain similarities in major phytochemical groups of R. serpentina and R. canescens justifies the use of R. canescens as a substitute for R. serpentina in traditional systems of medicine in Sri Lanka, which needs to be confirmed after further clinical trials. Keywords: Apocynaceae, Rauvolfia serpentina, Rauvolfia canescens, Polymorphological Characters, Phytochemical, PhysicochemicalItem Antioxidative Properties and Lactobacillus Population in Traditional Sri Lankan Pickle During Fermentation(Uva Wellassa University of Sri Lanka, 2014) Madusanki, K.S.The aim of this study was to determine the functional properties of the traditional Sinhala pickle. The antioxidant activity, pH variation and Lactic Acid Bacteria (LAB) population in Sinhala pickle was evaluated using different analytical techniques: DPPH free radical scavenging assay was used to determine the antioxidant activity. The results showed that there was a significant changes (P<0.05) in antioxidant activity during fermentation. Total phenolic content (TPC) in pickle extracts initially increased from 11.7353± 0.16 mg/ml to 15.0893± 0.58 mg/ml and started to decline. Antioxidant activity in pickle reduced after 96 hours storage time compared to that in 0 hours. The results showed that, pH was almost same during the 10 days of storage, and it consisted within the optimal pH level for growth of the LAB. And results present that the bacteria population increased from an initial number of 8.0997± 0.56 Logi ocfu/g after 24 hours fermentation at 37 °C. The maximum bacteria growth was observed as 9.4248± 0.23 Logi ocfu/g after 48 hour's fermentation. After three days storage at 37°C, the bacteria population decreased but, no significant difference was observed with the storage time at 37°C. The present study demonstrated that after second and third day of preparation LAB, and total phenolic content reached to their optimum value and after that they started declining. pH value remained almost constant and fermentation retained 90-95% Antioxidant capacity during the 10 day of storage at 37°C. Second and third days after the preparation, can consider as the best consumption period of pickle to gain the additional health benefits beyond their basic nutritional value. Keywords: Antioxidant activity, Lactic Acid Bacteria, Total Phenolic content, DPPH assayItem Automated Lunch Packet System(Uva Wellassa University of Sri Lanka, 2014) Lakmal, E.M.H.In hotel industries they are suffering about their labor cost. This research shows simple solution for reduce lunch packet time and labor cost. Also help to carry consistency of a lunch packet rather than packing by manually. Using mechanical system which control by PLC found the solution machine. Rice and curries are pre loaded in to the buckets in the machine. First stage of this machine can make approximately fifty lunch packets. Operator can select the type of lunch packet using control switch in machine. So using this machine reliable to the shop owner to count the number of lunch packets sold, no need to pay for a labor, and the efficiency will be increase.Item Antioxidant Activity of Selected Red and White Rice (Oryza Sativa L.) Varieties of Sri Lanka(Uva Wellassa University of Sri Lanka, 2014) Dodamgoda, G.H.D.I.U.Rice (Oryza sativa L.) is the dietary staple in Sri Lanka. There are thousands of different Sri Lankan traditional rice varieties and nearly fifty improved rice varieties cultivated in different agrochemical regions in the country. Rice bran is one of the most abundant co-products produced in the rice milling industry and research conducted in last two decades has shown that it contains a unique complex of naturally occurring antioxidant compounds. However, Sri Lankan rice varieties have not gained significant attention on measuring these antioxidants. Therefore, this study was conducted to evaluate the antioxidant properties of some Sri Lankan rice varieties. Freeze-dried 70% ethanolic extracts of brans of five white and six red rice varieties were screened for antioxidant properties in this study. Antioxidant properties of rice bran extracts of selected rice varieties were evaluated by using total polyphenolic content (TPC) (n=3), ferric reducing antioxidant power (FRAP) (n=6), 1,1-dipheny1- 2-picryl-hydrazyl (DPPH) radical scavenging (n=3) and 2-azino-bis (3- ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging (n=6) in vitro antioxidant assays. Significant differences were observed among bran extracts of selected rice varieties for investigated antioxidant properties (P<0.05). Mean TPC, FRAP , DPPH and ABTS antioxidant properties were in the range of 9.33 — 212.33 mg gallic acid equivalents/g of extract, 1.13 — 18.89 mmol Trolox equivalents (TE)/100g of extract, 2.85-43.32 inhibition %, 23.93-98.34 inhibition % for 1 g rice bran respectively. Resulted mean values of the antioxidant activity of red rice varieties, for all four assays were significantly higher than that of white rice varieties. It is concluded that brans of Sri Lankan rice varieties, especially red rice varieties have higher antioxidant properties and could be use as potential sources for the prevention of chronic degenerative diseases in Sri Lanka. Key words: rice bran, antioxidant, in vitro, assay, chronic degenerative diseasesItem Microbiological Analysis of Broiler Chicken Production Line at Haira Group of Company (Pvt) Ltd, Ulappana(Uva Wellassa University of Sri Lanka, 2014) Asaka, M.I.F.In the past few years concern regarding food safety has increased among consumers due to continues reports of food borne outbreaks and food poisoning in many food establishments. Literature reveals that the meat industry is the most critical food sector to ensure the safety of the final products. Hence food safety is the most important factor to ensure consumer health from harmful effects. Present study was aimed to identify the potential biological hazards associated with the process of broiler chicken production in Haira processing plant at Ulappana. Initially the process flow diagram was constructed and all possible production steps were evaluated for microbial contamination. Microbial testing was conducted for the most potential pathogens in raw chicken meat including E. coli and Fecal coliform. Obtained data were analyzed using Dunnett comparison test against standard microbial limits using Minitab 16 statistical package at 0.05 significant differences. According to the results scalding, evisceration and freezing processing steps were considered as most critical points in this production line. Critical limits and possible preventive methods were suggested with the consideration of government regulations, company policies and scientific data from several literature sources to achieve safe broiler production. Key words: - Food borne outbreak, critical limit, biologically critical pointsItem Kinetics Modeling of Partial Degradation of Carbofuran by Pyrite(Uva Wellassa University of Sri Lanka, 2011) Dhanasekara, S. A. K. M.The zeta potential of pyrite and pyrite-carbofuran suspensions was examined as a function of pH and the chemical kinetics of carbofuran was examined in the presence of pyrite as a function of pH and adsorbent loading. The pHiEp of pyrite was around 1.70 when inert environmental conditions were maintained. In the presence of carbofuran, the pHIEp shifted from 1.70 to —3 and the zeta potential has increased indicating direct surface interactions. The carbofuran degradation was also evidenced by time resolved IR spectroscopic measurements. Conventional kinetic experiments showed that the degradation is pseudo-first order with respect to carbofuran concentration. When the initial pyrite loading is increased by about 10 fold, the reaction order of carbofuran degradation has transformed from 0th to pseudo 1st order indicating a surface mediated mechanism. This mechanism of carbofuran degradation is largely ascribed to a Fenton like process. In the presence of pyrite at acidic pH, the carbofuran degrades via two routes: cleavage of the C-N bond forming carbamate and 2,3-dihydro-2,2-dimethyl benzofuran-7-al formate, and cleavage of the C-0 bond forming methylamine and 2,3-dihydro-2,2-dimethylbenzofuran-7-ol. The resulted carbamic acid is unstable and, therefore rapidly degraded to methylamine and CO2. In agreement with mass spectroscopic data, a simple kinetic model was proposed as required for design of a unit process in drinking water treatment.Item Obstacle Detection and Navigation of a QuadRotor Using Image Processing With Overhead Mounted Camera(Uva Wellassa University of Sri Lanka, 2017) Prabhashitha, R.D.Obstacle avoidance system for a Quadrotor using image processing technique using over head mounted camera. The robots that existing uses various sensors to obtain location of obstacles and navigate without colliding with the them here the robot only uses a camera to detect obstacles and navigate around the obstacles without colliding. By using this method robot does not need additional sensors to detect obstacles. Here the method using image processing technique and the software used is MATLAB software package. Images from overhead web camera converted to gray scale images and filtered to remove any noise and then converted to binary image and objects in the image identified and centroid is drawn and square is drawn around the robot to distinguish in between. Then pixel location of each object taken from the centroid pixel and area of the objects are also taken in to consideration when navigation is done. The navigation part is done by the depth first search algorithm. It uses location of the robot to navigate to the goal node in the image binary matrix. The results of this project was that successful navigation of a mobile robot using overhead mounted single camera without any sensor. And for Quadrotor this algorithm was simulated on Robotic Operating System(ROS) and Dronekit Simulation environments. These environments were built on Ubuntu operating System and a Python script was used to connect MATLAB program. Tests were successful when detecting obstacles and generating navigation path. The conclusion of this research that this method is suitable for applying for any mobile robot for a specific range this method can be used for Quadrotor also by defining same parameters as for the mobile robot.Item Development of a pH Responsive Ceramic Material(Uva Wellassa University of Sri Lanka, 2017) Mahanama, M.G.C.Not only human been as well as all the animals consume food items daily. They cannot continue their lives without food items. Food spoilage is a big problem to the food industry. Because of the bacteria and other microorganisms acted in food items. This cannot be overcome but able to be controlled. In food industry the most difficult thing is to identify the food whether it is spoiled or not. From this research that blank will be fulfilled. Because this research introduces a pH sensitive smart bottle cap. When the pH is going to change this pellet will be easily identified by giving a color change. When some food item is being spoiling, there will be produced lactic acid. Because of acidic condition pH will be reduced. That pH variation can be identified by pellet. Kaolin is the ceramic material which is used in this research. Here it used kaolin because of non-toxicity & chemical inertness. Then kaolin material prepare for the condition which can absorb dye material as well as to obtain clear view of color change. This research used four types of dye materials. Two of them are consisted with anthocyanin and other two are commercial dyes. Anthocyanin can undergo molecular rearrangement due to polyphenolic group and extended conjugation of double bond depending of pH of medium. Also in methyl orange and methyl red, they show different colors in acidic and basic conditions. Other important thing is those dyes are low toxicity and may not be able to effect to the food item. The main objectives of this research are checking the air stability of these dye, prepare the pH series of dyes and check whether how they react with the dyes, check whether the dye absorbed pellets are reacted with the acidic, basic conditions as well as spoiled and non spoiled milk and finally develop the bottle cap. The air stability of those four dye materials have been checked by the UV visible spectrometer. For the red cabbage, there were increased of absorbance gained after 72hours. The pH reduction average is 34.04% after72 hours. Same as the Hibiscus dye also shown, a increase of absorption and reduction average of pH 25.35% after one day. Same as methyl red dye, it shows 11.7% increase of absorption after one day. Also it shows 20.045% of pH reduction after one day. In methyl orange, it shows 67.67% of absorbance increase and 19.3% of pH reduction. ii Red cabbage absorbed pellets show yellow color for the 1M sodium hydroxide and pink color for the 1M sulfuric acid. For the spoiled milk blue color pellet shifted to the purple as well. Same results were obtained for the Hibiscus dye. Methyl red shows yellow color for 1M NaOH & red color for 1M sulfuric acid. Also it shows brownish color for the spoiled milk as well. Methyl orange dye shows yellow color for the 1M NaOH and no color change obtained for the 1M sulfuric acid. Then it shows brown color with the spoiled milk as well.Item Object Sorting System Using an Affordable Robotic Manipulator(Uva Wellassa University of Sri Lanka, 2017) De Silva, A.M.O.Industrial automation and robotics are at a high demand in the industry in present as both of them directly affect the growth of the industry. Quality and flexibility of the product is becoming significant criteria for the industry. Robots are the best solution for future cost of labor wages and higher customer demands. Robotics and automation are combining in order to replace human labor to perform their tasks that are routine, dangerous, complex and in hazardous area. Pick and place operations are needed in every kind of manufacturing process and it can be automated. So, this project aims to sort and place different objects according to their topside shape using image processing technique. In this project, low cost, servo motor controlled, CNC machined 5 DOF robotic manipulator with pneumatic suction end effector is used for the object sorting. The shape detection is implemented using Matlab 2016 and a high quality logitec web camera is used for image capturing. The robotic manipulator is controlled through an Arduino Mega via serial connection to Matlab. A graphical user interface is developed with customization options. The main objective is to provide a solution for any manufacturing process which require sorting based on shape, color or their combination. Keywords: Robotic, Matlab, Arduino, Automation, Shape, SortingItem Development of Cathode Material for Lithium Ion Rechargeable Batteries Based on the System Li(Niv3Mnii3C01/3 _Nax, 002 x = 0.02 , 0.06(Uva Wellassa University of Sri Lanka, 2017) Warsapperuma, W.A.M.H.Expensiveness of electrode materials, such as LiCo02, is recognized as one of the main barriers that prevents the development of the rechargeable Lithium Ion Batteries (LIB) from reaching the common masses. Therefore, layered transition metal oxides such as Li(Niii3Mni3C01/3)02 are presently being investigated as an alternative cathode material. Moreover, substitution of Na in transition metal oxides of Ni, Mn and Co (NMC) has been identified as an effective strategy to improve their ele'ctrochemical performance. The present work attempted to synthesize Li(Niv3Mn 13C01/3-xNa 002 x = 0.02 and 0.06 through substituting expensive Co by cheaper Na, using Glycine Nitrate Combustion (GNC) method. The GNC is an effective method to synthesize sub-micron size particles formed by agglomerating primary nano scale particles. This particle morphology is chemically stable and provides greater rate capability and electrochemical performance. Li(Niu3Mnit3C01/3-xNax)02, x = 0.02 and 0.06, oxide powders were synthesized by GNC method keeping the Glycine:Nitrate ratio as 0.6, by calcining at 900 °C for two hours. This process is a simple and single step process with a low calcination period. Scanning electron microscopy showed that the synthesized powder consists of quasi-spherical, secondary particles formed by aggregating nano-scale primary particles. Chemical analyses of synthesized powders reveal that the composition of these synthesized samples was close to stoichiometric ratio given by its empirical formula. Fourier transform infrared spectra of Li(NiIRMn1RCo1/3-xNax)02 x = 0.02 and 0.06 are characterized by IR absorption bands in three distinct regions. These bands represent the characterized chemical bonds in layered metal oxides with a-NaFe02 structure. The four probe D.C. electrical conductivity measurements performed on the dense sintered pellets showed enhanced electrical conductivity in these novel materials compared that of base material, Li(Ni1/3Mnii3Coi/3)02. Hence this study revealed the possibility of preparing cheaper Li(Ni1i3Mnii3C01/3-xNax)02 by GNC method, for the intended LIB cathode applications.Item Vehicle Speed Limit and Lock for Drunken Drivers(Uva Wellassa University of Sri Lanka, 2017) Varjith, T.This paper is giving a new approach on the section of the safety procedure of the automobile industry. By giving a technique that can be implemented to decrease the accidents happen by the drunken drivers. This technique is implemented with a smart system that monitors the driver for the presence of any alcohol level in their body by constantly checking the breath of the driver. As alcohol is very evaporative material the checking procedure is done by placing an alcohol sensor in the steering of the vehicle which will monitor the presence of alcohol molecule near the surrounding of the driver. The speed of the vehicle varies according to the content of alcohol detected. Vehicle countermeasure system constantly adjust the speed of the vehicle normal speed level of 100 km/h. 80% of speed for 0% to 20% of alcohol level, 30% to 30 % of alcohol 70% of full speed, 30% to 40% of alcohol 60% of full speed, 40% to 70% of alcohol level 50% of full speed and when alcohol level is more than 70% the vehicle slowly decrease its speed and the engine ignition off. The Global positioning system (GPS) measure the latitude and longitude values and sends the information to the responsible person along with a one-time password that switch on the ignition system again as a message using the GSM module. All the processes and function in this project are aided with the controller Raspberry Pi 2.Item Determination of the Insect Repellent Activity of Herbs on Sitophillus Oryzae(Uva Wellassa University of Sri Lanka, 2017) SAJITHTHA, B.Natural products from plants are known as secondary metabolites. These compounds show several biological properties including insecticides activity. Storage losses in paddy alone have been estimated to be 4-6% and it had been estimated that 80% of this loss is due to insect attack. Based on, this research mainly focused on to protect the rice from Sitophilus oryzae by using herbal plant extraction. In Sri Lanka, only a limited number of studies have assessed the insecticides properties of herbs. Therefore, in this study, insecticides activities of selected three herbs species and their cytotoxicity were tested. Samples were collected from near to university premises. Using methanol extraction, herbs was extracted from three species,Cinnamomum cassia, Plectralthus amboinicus, and Aglaia roxburghiana . plant extract were tested for their insecticidal activities against adults of Sitophilus oryzae, using direct contact application. Responses varied with plant material, insect species, and exposure time. Testing was carried out for different concentrations of extracts (153.06 fig/cm2, 458.18 tg/cm2 and765.30). Insecticidal activity and best plant were discovered for Sitophilus oryzae . Methanol extracts of all plans showed insecticidal activity against tested insects. Best plant/s and part/s is leaf of Cinnamomum cassia, and least insecticidal activity shows Plectralthus amboinicus leaf. Toxicity assay was done to test the toxicity of plants. Artemia salina was used for toxicity assay. The results from toxicity assay, a leaf of Aglaia roxburghiana is having the high toxic and leaf of Plectralthus amboinicus is having the lest toxic. The results from this study confirm insecticidal activity in Aglaia roxburghiana, Plectralthus amboinicus and Cinnamomwn cassia. Further research is needed to identify the individual compounds responsible for insecticidal activity, which may in turn lead to developing natural insecticides from locally available herbs. Key words: Insecticidal activity, cytotoxicity and secondary metabolites.Item Designing and Development of A Fully Automated Solar-Powered Lawn Mower(Uva Wellassa University of Sri Lanka, 2017) Pakirathan, R.This Project aimed to design a fully automated solar-powered lawn mower (FASPLM) of electrical source to reduce the environmental pollution and use the natural resources in effective way. This device consisted of a square cross sectional cutting thread which is operated by the efficient powered motor and the power supply for the motor is given by a rechargeable battery. The battery can be charged by using a solar panel. The obstacles in the moving path of the mower can be sensed by an ultra-sonic distance sensor to avoid the obstacles in the track. Moreover, it has PIR sensors for detecting the human motion near the lawn mower. This design requires no perimeter wires to maintain the mower within the lawn and it will avoid and detect objects and human motion as it uses a self-localization platform with a global positioning system (GPS) module to travel and uses efficient cutting algorithms. Initially, the market survey and literature survey were carried out to study the advantages and disadvantages of the existing devices. Then according to the survey results, a suitable platform for the lawn mower was designed. Thereafter, a detailed mechanical design and the mechanical structure were developed. Then the mechanical structure was fabricated, following that mechanical parts and the electronic wiring were assembled. The control algorithms and coding were written appropriately. Finally, manufactured equipment was tested in the field. The major drawbacks of this device are with navigation control and duration of battery life. This lawn mower used GPS for localization and track following, coding and mechanical construction of GPS module is little difficult. Furthermore, during the long time of operation the battery discharging rate may be greater than the charging rate, therefore it is expected to use efficient motors, and efficient solar panels to keep the battery for long time operation.Item Automated Forklift Scheduling System(Uva Wellassa University of Sri Lanka, 2017) Madushanka, K.R.In the manufacturing organizations, forklifts can be seen and they are being used to carry various things that cannot be handled by humans. In Sri Lanka, most organizations don't follow any proper way to inform the forklift drivers about the jobs available. Forklift drivers has to be informed for the jobs manually. In this dissertation, a system to handle the forklifts more efficiently is described. This system can save time as well as can increase the productivity and it is cost effective. This research is mainly based on Arduino and GSM technology is used as well for the communication method. GSM technology is fast improving technology and it use for various projects in modern world. It is a good communication method than the other communication methods because the noises or the disturbances that can be occur during the communication is lower than the other types of communication methods. Arduino is used for all the processing parts and GSM module is used for the data transmission. There are two types of communication units were designed for the forklifts and the machines or the area of the work floor that produce the jobs for forklifts. When a product finished in the production machine it will automatically send a SMS or when a job is available in the working area, a laborer can send a SMS to all the units in forklifts and indicate about the job to the forklift drivers. Then they can either accept the job or they can reject the job. Multiple drivers can response to the job alert. The first person how respond to the job alert will receive the job and others will be informed about it. All the indications of the system are done using leds, to understand easily and make the attention of the forklift drivers.Item Different Methods of Extraction of Lignin from Coconut Sawdust: The First Step of Development of Lignin-Based Polyurethane Thermoplastics(Uva Wellassa University of Sri Lanka, 2017) JAYAWARDANA, D. D. H. C.Lignin is one of the major polymers found in the cell wall of plant biomass. It is a heterogeneous, high molecular weight and cross-linked polymer containing three major phenolic compounds, coniferyl alcohol, sinapyl alcohol, p-coumaryl alcohol. One approach for a value-added utilization of lignin is the synthesis of lignin-containing copolymers. One of the most utilized strategies is copolymerization to form polyurethane, where lignin serves as the hard segment in the polyurethane structure. Hydroxyl groups on lignin readily react with isocyanates to form polyuiethanes. With increasing concern of the shortages of fossil resources and the impetus for reducing costs of polyurethanes, preparation of polyols from waste biomass will be an interesting subject in the polyurethane industry. Especially for Sri Lanka, it is very actual and perspective to replace petrochemicals if possible since petrochemicals are not economical due to high exportation cost. Extraction of most of the lignin from its mother source is very vital for cost reduction. In this study as a first step of the long-term research, lignin was extracted from sawdust of coconut palm (Cocos nucifera), which is a common waste material and identified as a rich source of lignin by two different methods; acid lignin extraction and alkaline lignin extraction. It was found that the percent yield obtained from acid hydrolysis was higher than that from alkaline method. The lignin obtained from both methods was characterized by FTIR and UV-Visible spectroscopy. Further, the phenolic OH content of the acid insoluble lignin samples were calculated.Item Automated Plates Washer(Uva Wellassa University of Sri Lanka, 2017) Herath, H.M.A.D.K.Washing plates normally done by hand and it uses water, energy, chemicals as well as need to spend valuable time. So an efficient approach can save a lot of each. Though the dish washing machine gives some relief for that, the existing dishwashing machines in the world market consist many defects in the system such as wastage of water, requirement of man power, high installation cost, poor quality of cleaning etc. Specially, there is no proper turning off system when the washing is complete, and because of that it waste large amount of water. This project is about inventing an Automated plates washer which can be overcome the problems in existing machines. It includes automatically turning off system after the plates are cleaned. The system is controlled by arduino and has to supply high pressure water to the machine to start the washing process. Then the sensor will give the signal to turn off the machine when the process is complete. This system can be used in large scale kitchens such as in marriage ceremonies, receptions, business parties, etc. where there is requirement of more number of plates. Not only that this plate washer is useful for household use as same as the washing machine, which can save time and cost rather than spending in washing plates by hand and wasting large amount of energy.Item Synthesis and Characterization of Hydroxyapatite Derived from Eppawala Apatite for Bio Medical Applications(Uva Wellassa University of Sri Lanka, 2017) Hapuhinna, H.K.G.K.D.K.Hydroxyapatite is widely used as a bio implant material because of its chemical and structural similarity with' the mineral phase of bone and teeth. However, synthesize of this material from natural minerals is not that much popular. Here, we synthesized hydroxyapatite from apatite (high grade phosphate) available in Eppawala, Sri Lanka as a value added product. The synthesize procedure was carried out using two different methods i.e. sol-gel method and solid-state pressure less sintering. Synthesizing by sol-gel method was done in two different ways. The first method was mixing apatite with ethanol and the second method was mixing apatite with diluted nitric acid. The solid:state pressure less sintering was done by mixing apatite with calcium hydroxide. The obtained hydroxyapatite powders were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction spectroscopy (XRD) and Scanning Electron Microscopy (SEM) in order to identify their structtu-e i.e. types of bonds and available functional groups, its crystallinity and the surface morphology respectively. Our FTIR results show that the presence of hydroxyl groups and it is confirmed the formation of hydroxyapatite from apatite. Our XRD data show the reflections corresponding to structure of hydroxyapatite and the microstructural features of products explained through the SEM results. All FTIR, XRD and SEM results were compared with the literature data and it is revealed that the possibility of formation of hydroxyapatite from Eppawala high grade phosphate available in Sri Lanka. Keywords: Hydroxyapatite, Eppawala high grade phosphate, Sol-gel method, Solid state sinteringItem Nano Carbon Materials Based on Purity Enhanced Sri Lankan Flake Graphite(Uva Wellassa University of Sri Lanka, 2017) Dilanthika, D.G.I.Even though there are many studies on Sri Lankan vein graphite, less attention has been paid to investigate Sri Lankan flake graphite. This is partly due to unavailability of high purity flake graphite samples. Besides the deposits present (if) around the country have been not properly identified and located. The flake type of graphite is the main type of graphite available in the other parts of the world, which some countries like China produces at mass scale and is used in number of industrial applications. Although the vein type of graphite available in Sri Lanka has been used in many industrial and research applications ever since they are found, the flake type (if present) has never been explored for its use, mainly due to the problems mentioned above. As vein type is unique to Sri Lanka and has intrinsic properties (that are partly due to geological reasons), one can raise a fair question as to whether the flake type will also have the same uniqueness to SL, hence having intrinsic properties compared to those widely available in other parts of the world (as geology plays a vital role in materials properties). If that is the case, then there is a possibility of developing tailor made applications from SL flake graphite based on properties. However in order to achieve this, one's first target should be to isolate purified flake graphite samples sufficient for a range of investigations. Therefore this research work concentrates on isolation and purification of flake graphite from its deposits and synthesis of carbon based nanomaterials using thus purified flake graphite. The carbon based nanomaterials produced using purified flake graphite are graphene oxide and reduced graphene okide. The results of this work proved the possibility of purification and the use of this purified flake graphite for the synthesis of graphene based materials. Flake graphite samples collected from Pasyala area in South Western region were first purified and then were used to synthesis of graphene oxide and reduced graphene oxide. The process was started with the purification of flake graphite powder. Then the chemical oxidation was used to convert the graphite powder into graphene oxide using Improved Hummer's method. Graphene oxide was then reduced using a chemical reduction method which converted graphene oxide to reduced graphene oxide. The nanocarbon samples were characterized using Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Energy-Dispersive X-Ray Absorption Spectroscopy (EDXAS) and DC electrical conductivity of purified graphite, graphene oxide, reduced graphene oxide was measured using Four-Probe DC conductivity method.Item Antimicrobial Activities of Endophytic Fungi Isolated from Fimbristylis Miliacea(Uva Wellassa University of Sri Lanka, 2017) Sivakumaran, A.Endophytes are known to biosynthesis various bioactive secondary metabolites. Sri Lanka has a high rate of endophytic fungi of Cyparaceae Plant. Grasses and sedges are reported to harbour a lot of endophytic fungi & sedges are sparsely investigated for endophytic fungi and bioactive metabolites. Therefore the aim of this study is investigation of the antimicrobial activities of the endophytes of Fimbristylis miliacea, which may lead to the discovery of new drugs. Endophytic fungi were isolated from the surface sterilized roots and aerials parts of F.miliacea collected from Badulla & Mawanella and the antimicrobial activities were evaluated against S.aureus, P. aeruginosa, E.coli & B.cereus at 400 µg/disc concentration using agar disc diffusion method. The two most bioactive fungi were identified by morphological features and slide cultures. Ten & twenty morphologically distinct endophytic fungi were isolated from Badulla & Mawanella respectively. All the ten extracts from Badulla showed activity for at least one bacterium tested. Three extracts showed activity against all the four bacterial species while six extracts showed activity against three bacteria tested. Prominent activities (16 and 13 mm inhibition zones) were shown by the extracts FMR4 and FMR6 against B. cereus. The two most bioactive fungi FMR4 & FMR6 were tentatively identified as Fusarium sp. In conclusion, the data obtained from the current study revealed F. miliacea harbor endophytic fungi which produce secondary metabolites with antibacterial activities. Keywords: Endophytic fungi, Secondary metabolites, Fimbristylis miliacea, Antimicrobial, Fusarium sp.Item Development of Ag20/Zno Composite Photocatalyst for Methyl Orange Degradation(Uva Wellassa University of Sri Lanka, 2015) Gunarathna, T.M.S.Environmental pollution is contamination of the Biological, Physical and the Chemical components of the Land, Water and Air. It can cause harm or discomfort to the humans or other living organisms in the environment. Dyes may adversely affect the aquatic life because of the presence of aromatic materials, metals and chlorides. Therefore, for water treatment processes, dye removal is important. This study is focused on development of a composite material to remove organic pollutants in waste water. Model pollutant used in this study is Methyl Orange (MO) and composite is Ag20/ZnO. Then the capacity of Ag2O/ZnO to act as a photocatalyst to degraded organic dyes was evaluated and find optimum conditions/ composition of the composite. Results indicate the composite material can successfully degrade MO under visible light. The highest degradation rate which 74% was observed for the optimum composition of Ag2O: ZnO ratio 3:5. To find the concentration of the unknown solution used an equation known Beer's law, A = s 1 c, Where A is absorbance, c is the molar absorptivity, 1 is the path length and c is concentration of the solution. The degradation efficiency is calculated by Degaradation%= (A-Ao) / Ao * 100 Where Ao represents the initial absorbance, A represents the reaction absorbance of the MO at the characteristic absorption wavelength of 465 nm. Freundlich adsorption isotherm is used, x/m = kpl/n or log x/m = log k + 1/n log P Where x is the mass of the gas adsorbed on mass m of the adsorbent at pressure p and k, n are constants whose values depend upon adsorbent and gas at particular temperature.