Sri Lankan Journal of Physics最新文献

{"title":"Enhanced photovoltaic effects of dye-sensitized solar cells of SnO 2 surface modified with gold nano particles","authors":"G. Aponsu, R.C.L. De Silva, V. Perera","doi":"10.4038/SLJP.V9I0.2508","DOIUrl":"https://doi.org/10.4038/SLJP.V9I0.2508","url":null,"abstract":"The photovoltaic properties of dye-sensitized solar cells of SnO 2 are improved by depositing gold nano-particles on the surface of SnO2 particles. The enhancement of the efficiency is attributed to increment of both the photocurrent and the photo voltage of the cells. This is described by the shift of the conduction band edge of SnO 2 to a higher energy level when SnO 2 particles are in contact with gold nano-particles. DOI: http://dx.doi.org/10.4038/sljp.v9i0.2508 Sri Lanka Journal of Physics Vol.9 (2008) pp.27-34","PeriodicalId":21880,"journal":{"name":"Sri Lankan Journal of Physics","volume":"32 1","pages":"27"},"PeriodicalIF":0.0,"publicationDate":"2010-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78475578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Properties of solid-state ZnO|dye|CuCNS solar cell","authors":"P. Sirimanne, Jb B. Zhang","doi":"10.4038/SLJP.V9I0.2506","DOIUrl":"https://doi.org/10.4038/SLJP.V9I0.2506","url":null,"abstract":"Hybrid ZnO films were prepared via a single-step electrochemical process. Extraction of organic component from the hybrid films resulted tiny ZnO columns perpendicular to the substrate. A Semiconductor hetro Junction was prepared by depositing CuSCN on ZnO films. The maximum photocurrent of 0.36 mAcm -2 and photovoltage of 290 mV were observed for the solid-state cell fabricated by sandwiching organic dye mercurochrome in between ZnO and CuSCN films. DOI: http://dx.doi.org/10.4038/sljp.v9i0.2506 Sri Lanka Journal of Physics Vol.9 (2008) pp.7-18","PeriodicalId":21880,"journal":{"name":"Sri Lankan Journal of Physics","volume":"25 1","pages":"7"},"PeriodicalIF":0.0,"publicationDate":"2010-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87314634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of electrochemically prepared CuSCN films and their capabilities of application in dye sensitized photovoltaic cells","authors":"PM Sirimanne, Jb B. Zhang","doi":"10.4038/SLJP.V9I0.2507","DOIUrl":"https://doi.org/10.4038/SLJP.V9I0.2507","url":null,"abstract":"CuCNS was deposited on conducting glass substrates by cathodic electrochemical technique using rotating disc electrode. CuCNS films exhibited transparency over 85% for visible light. High transparency of these films suggests capability of utilization as an optical window in photovoltaic cells. Cathodic photocurrent was observed on sensitized CuCNS electrodes when in contact with an electrolyte. An enhancement in photocurrent was observed under back wall mode than front wall mode illumination on photocathode. DOI: http://dx.doi.org/10.4038/sljp.v9i0.2507 Sri Lanka Journal of Physics Vol.9 (2008) pp.19-26","PeriodicalId":21880,"journal":{"name":"Sri Lankan Journal of Physics","volume":"1 1","pages":"19"},"PeriodicalIF":0.0,"publicationDate":"2010-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82349334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement of Noise within Passenger Trains on a Costal Railway Line","authors":"N. S. Pahalavithana, D. Sonnadara","doi":"10.4038/SLJP.V10I0.3833","DOIUrl":"https://doi.org/10.4038/SLJP.V10I0.3833","url":null,"abstract":"The noise levels within passenger trains operating on a coastal railway line is presented. It was found that the engine noise is the main source of traction noise. Its contribution to the overall noise level within the passenger compartments was analyzed, and, the effect of engine noise on the passengers has been discussed. Noise enhancement due to external objects in close proximity to the railway line was carried out in order to assess the total noise exposure of the passengers in a train traveling on the costal railway line. In general passengers are exposed to average noise levels around 75 dB which can reach 85 dB in passenger compartments close to the engine of the train. A simple noise prediction model is proposed which was successful in predicting the average noise level within passenger compartments in trains running between two adjacent stations along the selected coastal railway line. Keywords: Railway noise; Environment regulations; Passenger trains; Sri Lanka railways DOI: http://dx.doi.org/10.4038/sljp.v10i0.3833 Sri Lanka Journal of Physics, Vol. 10 (2009) 25-37","PeriodicalId":21880,"journal":{"name":"Sri Lankan Journal of Physics","volume":"72 1","pages":"25"},"PeriodicalIF":0.0,"publicationDate":"2009-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76161063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deformation behavior of elastomeric networks studied by deuterium nuclear magnetic resonance ( 2 H NMR)","authors":"P. Ekanayake","doi":"10.4038/SLJP.V10I0.3829","DOIUrl":"https://doi.org/10.4038/SLJP.V10I0.3829","url":null,"abstract":"Deuterium nuclear magnetic resonance ( 2 H NMR) was used to test a theoretical framework that has been introduced to explain the 2 H NMR line splitting of uniaxially stretched partially deuterated poly(butadiene) elastomers. The theory attributes the higher degree of anisotropy implied the splitting to the interchain steric interactions. From the fitting parameters the separate contributions to the average orientation of the chain segments arising from the network constraint and from the interactions are calculated. DOI: http://dx.doi.org/10.4038/sljp.v10i0.3829 Sri Lanka Journal of Physics, Vol. 10 (2009) 1-5","PeriodicalId":21880,"journal":{"name":"Sri Lankan Journal of Physics","volume":"25 1","pages":"1"},"PeriodicalIF":0.0,"publicationDate":"2009-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85168631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First use of NMR diffusometry for the determination of core size distributions in core-shell latex films","authors":"P. Ekanayake, J. Keddie","doi":"10.4038/SLJP.V10I0.3832","DOIUrl":"https://doi.org/10.4038/SLJP.V10I0.3832","url":null,"abstract":"Latex films cast from core-shell particles were characterised for the first time using restricted diffusion measurements obtained with a five-pulse steady-gradient stimulated echo (SGSE) nuclear magnetic resonance (NMR) technique in which all nuclear spin relaxation losses were kept constant. The latex particles, which were made via miniemulsion polymerization, consist of an acrylic shell and a poly(dimethyl siloxane) (PDMS) core. It was found that the particle core remains intact after film formation. The average sizes and distributions of the PDMS phases were determined. Unlike various microscopies, NMR diffusometry provides a powerful means for obtaining quantitative information about the average microstructure in an entire film. DOI: http://dx.doi.org/10.4038/sljp.v10i0.3832 Sri Lanka Journal of Physics, Vol. 10 (2009) 17-24","PeriodicalId":21880,"journal":{"name":"Sri Lankan Journal of Physics","volume":"56 1","pages":"17"},"PeriodicalIF":0.0,"publicationDate":"2009-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85776450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling and Simulation of Environmental Disturbances for Six degrees of Freedom Ocean Surface Vehicle","authors":"D. Sandaruwan, N. Kodikara, R. Rosa, C. Keppitiyagama","doi":"10.4038/SLJP.V10I0.3834","DOIUrl":"https://doi.org/10.4038/SLJP.V10I0.3834","url":null,"abstract":"In this paper we focused on Modeling and Simulation of environmental disturbances for ocean Surface Vehicle. We developed ship simulation system for simulating ship motion in a virtual environment with respect to environment disturbances such as sea wave, wind and sea currents. This system simulates ship motions in six degrees of freedom, pitch, heave, roll, surge, sway, and yaw. This system is simple and responds in real-time to interactions and it is based on a mathematical ship model. The mathematical ship model is derived from the non-linear speed equations, Newton’s laws, fluid dynamics and other basic physics. We use multivariable functions to model the ocean surface with superposition of sinusoid functions and the ship model requires fewer amounts of ship data and the mathematical ship model can be used with different types of ships and it can be used in real time virtual reality applications. DOI: http://dx.doi.org/10.4038/sljp.v10i0.3834 Sri Lanka Journal of Physics, Vol. 10 (2009) 39-57","PeriodicalId":21880,"journal":{"name":"Sri Lankan Journal of Physics","volume":"65 1","pages":"39"},"PeriodicalIF":0.0,"publicationDate":"2009-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89158293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Upwelling phenomena in the southern coastal waters of Sri Lanka during southwest monsoon period as seen from MODIS","authors":"K. Yapa","doi":"10.4038/SLJP.V10I0.3831","DOIUrl":"https://doi.org/10.4038/SLJP.V10I0.3831","url":null,"abstract":"MODIS (Moderate-resolution Imaging Spectroradiometer) aqua data for 2004 has been used to explore possible coastal upwelling areas around Sri Lanka during southwest monsoon. Two very important ocean parameters, ocean colour and sea surface temperature (SST), derived from MODIS data for the waters surrounding Sri Lanka are studied to understand the variability and the relationship of the two data sets. Remotely sensed data of 1.1 km resolution obtained from MODIS were mapped using seadas software within an area of latitudes between 2.0 N - 13.5 N and longitudes between 72.5 E – 88 E. The days with heavy clouds were excluded. Daily chlorophyll a and SST maps were used to make composites for each week and subsequently for each month. There were between 10 – 20 daily files for each month. The southwest monsoon period arrives roughly in May and generally lasts till September. The chlorophyll concentration varies roughly in the range 0.01 – 10.0 mg m −3 and the sea surface temperature varies between 25 – 32°C in the waters surrounding the island during the year. The monthly composites of chlorophyll a show high productive waters of over 5 mg m −3 average concentration in most of the southern and western coastal ocean during the months of June - August. The sea surface temperature drops by 2 to 3 degrees (centigrade) in coastal ocean waters in the south where high chlorophyll a concentrations are detected. Observation of chlorophyll a and SST maps indicate strong correlation (between 60% - 80% of negative correlation) between the two parameters in the southern coastal ocean region where high chlorophyll a and low SST values are detected in the months of June and July. This may be due to the upwelling phenomenon that occurs in the coastal waters. Upwelling brings cooler nutrient rich waters to the surface enhancing the production of phytoplankton near the surface waters and these high phytoplankton areas are generally attracted by large fish populations. Thus, correct identification of upwelling zones would be highly beneficial in the fishery industry. Key words : MODIS; sea surface chlorophyll a ; SST; southwest monsoon; upwelling DOI: http://dx.doi.org/10.4038/sljp.v10i0.3831 Sri Lanka Journal of Physics, Vol. 10 (2009) 7-15","PeriodicalId":21880,"journal":{"name":"Sri Lankan Journal of Physics","volume":"40 4 1","pages":"7"},"PeriodicalIF":0.0,"publicationDate":"2009-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75848039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Artificial muscles based on Polyacrylonitrile based polymer electrolyte","authors":"K. Perera, K. Vidanapathirana, M. Dissanayake","doi":"10.4038/SLJP.V8I0.212","DOIUrl":"https://doi.org/10.4038/SLJP.V8I0.212","url":null,"abstract":"A system capable of converting chemical energy into mechanical energy can be treated as an artificial muscle or an actuator. Direct drive actuators incorporating materials like ferroelectric ceramics and piezoelectric polymers suffer from various limiting factors. It has been realized that polymers can be used to fabricate such muscles with appreciable performances. Movement of the muscles takes place as a result of incorporation and ejection of ions. In this study, the fabrication of a dry muscle using a Polyacrylonitrile (PAN) based electrolyte and two polypyrrole (PPy) electrodes and investigation of its performance is discussed. The composition of the polymer electrolyte was 21mol%PAN : 39mol%EC : 33mol%PC : 7mol%LiCF3SO3) and it has a good mechanical stability. Two identical polypyrrole electrodes have been polymerized in the presence of dodecylbenzenesulfonate (DBS). An assembly of PPy : polymer electrolyte : PPy was formed in the normal atmosphere. Movements were observed using cyclic voltametry technique. Simultaneously, horizontal displacement of the muscle was observed. A rough estimation was done about the velocity of the muscles during oxidation and reduction. During reduction, a faster movement was obtained.","PeriodicalId":21880,"journal":{"name":"Sri Lankan Journal of Physics","volume":"402 1","pages":"39"},"PeriodicalIF":0.0,"publicationDate":"2007-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78108137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electrochemical Properties of LiCo 0.4 Ni 0.6 O 2 and its Performances in Rechargeable Lithium Batteries","authors":"N. Balasooriya, P. Bandaranayake","doi":"10.4038/SLJP.V8I0.213","DOIUrl":"https://doi.org/10.4038/SLJP.V8I0.213","url":null,"abstract":"Intercalation cathode materials belonging to the 4-volt class electrodes, lithiated cobalt oxide LiCoO2 and lithiated nickel cobalt oxide LiCo0.4Ni0.6O2, were synthesized by sol-gel technique. The structural characteristics of the compounds were studied using XRD, FTIR and DSC. The compounds were used as cathode materials for assembling rechargeable lithium-batteries and their electrochemical performances were studied. The potentiostat and galvanostat techniques were used to determine the electrochemical characteristics. The irreversible capacity loss of LiCoO2 during the first charge-discharge is about 20% and for LiCo0.4Ni0.6O2 is about 90% for two different current rates of 5 and 10 A kg -1 . The overall electrochemical capacity of LiCo0.4Ni0.6O2 has been drastically reduced due to the s-block or p-block metal substitution. Also the un-reacted materials remained as impurities gave a very poor cycleability. However more stable charge-discharge performances have been observed for LiCoO2 at different current rates. Differences and similarities between these two cathode materials in batteries are also discussed. The Li-ion batteries were assembled using the sol-gel synthesized cathode materials, natural untreated vein graphite of Sri Lanka as the anode material and 1 M LiPF6 in EC/DMC as liquid electrolyte, and their performances were tested.","PeriodicalId":21880,"journal":{"name":"Sri Lankan Journal of Physics","volume":"16 1","pages":"47"},"PeriodicalIF":0.0,"publicationDate":"2007-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73987789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}