Sri Lankan Journal of Physics最新文献_第5页

Evaluation of a copper based gel polymer electrolyte and its performance in a primary cell 一种铜基凝胶聚合物电解质及其在原电池中的性能评价

Sri Lankan Journal of Physics Pub Date : 2015-01-27 DOI: 10.4038/SLJP.V15I0.6686

Y.M.C.D. Jayathilaka, K. Perera, K. Vidanapathirana, L. Bandara

{"title":"Evaluation of a copper based gel polymer electrolyte and its performance in a primary cell","authors":"Y.M.C.D. Jayathilaka, K. Perera, K. Vidanapathirana, L. Bandara","doi":"10.4038/SLJP.V15I0.6686","DOIUrl":"https://doi.org/10.4038/SLJP.V15I0.6686","url":null,"abstract":"Portable electronic device industry is vastly developing over the last few years. As electrochemical batteries are suitable power sources for portable devices, demand for reliable and efficient batteries have also been increased. Since liquid electrolytes can cause several safety hazards due to leaking of the electrolyte, studies on gel polymer electrolytes have been able to attract many researchers. In this research work, a gel polymer electrolyte based primary cell was fabricated and discharge characteristics were studied. To prepare the gel polymer electrolyte, Polymethylmethacrylate (PMMA), Ethylene Carbonate (EC), Propylene Carbonate (PC) and Copper trifluoromethanesulfonate (Cu(CF 3 SO 3 ) 2 - CuTf) were used. Gel polymer electrolyte sample which contained 22.5% PMMA: 30% EC: 30% PC: 17.5% CuTf showed a conductivity of 2.34 10 -3 S cm -1 at room temperature with an appreciable mechanical stability. Primary cell with Cu and Mg electrodes showed 1.73 V open circuit potential, 131 µA h capacity and 1.13 mA short circuit current. DOI: http://dx.doi.org/10.4038/sljp.v15i0.6686 Sri Lankan Journal of Physics, Vol. 15 (2014) 45-51","PeriodicalId":21880,"journal":{"name":"Sri Lankan Journal of Physics","volume":"30 1","pages":"45"},"PeriodicalIF":0.0,"publicationDate":"2015-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90472058","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}

引用次数: 1

Sodium nickel oxide nanoporous cathodes used for sodium-ion rechargeable batteries 用于钠离子可充电电池的氧化镍钠纳米多孔阴极

Sri Lankan Journal of Physics Pub Date : 2015-01-27 DOI: 10.4038/SLJP.V15I0.8021

R.C.L. De Silva, M. Jayaweera, V. Perera, I. Jayarathna, S. Rosa

{"title":"Sodium nickel oxide nanoporous cathodes used for sodium-ion rechargeable batteries","authors":"R.C.L. De Silva, M. Jayaweera, V. Perera, I. Jayarathna, S. Rosa","doi":"10.4038/SLJP.V15I0.8021","DOIUrl":"https://doi.org/10.4038/SLJP.V15I0.8021","url":null,"abstract":"The initial research on rechargeable batteries started focusing on both Lithium and Sodium but Lithium was more attracted because of its higher energy density. Later considering the cost of lithium, research has been directed to explore the possibility of using Sodium for rechargeable batteries because of its high abundance and low cost compared to Lithium. In this study we focuses on sodium Nickel oxide as the cathode material of the sodium iron rechargeable battery and tests were carried out to find the formation of crystal structure. Synthesis of Na x NiO 2 nonporous active material were made using solid state reactions at 700 ° C and the material development was studied by XRD characterizing technique. The developed Na x NiO 2 was used as the active cathode material in a rechargeable half cell. The characterization confirmed the crystal structure of NaNiO 2 to be monoclinic, and also its surface morphology. Electron transition status test revealed the specific energy band gap to be 5.16 eV. Charge transfer resistance of the cathode material obtained was 13,121 Ω. The further investigations on charge discharge revealed the maximum efficient charging rate per gram as 7.5 mA for 0.12 hours and maximum rate of discharge for maximum charge retention as 25 mA rate of charge per gram of Na x NiO 2 which was the active material of the rechargeable cell. The charge discharge cyclability was tested for Sodium Nickel Oxide with 0.2 mA constant current for both charging and discharging. A voltage of 2.34 V was observed as the open voltage (no load) at the beginning and the half cell showed more than 180 charge-discharge cycles in performance including a rest time of one minute for each cycle. This confirmed that the battery is able to hold a fairly high reversibility. DOI: http://dx.doi.org/10.4038/sljp.v15i0.8021 Sri Lankan Journal of Physics, Vol. 15 (2014) 19-29","PeriodicalId":21880,"journal":{"name":"Sri Lankan Journal of Physics","volume":"29 1","pages":"19"},"PeriodicalIF":0.0,"publicationDate":"2015-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82107531","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}

引用次数: 4

Synthesis, characterization and ethanol vapor sensing performance of SnO2/Graphene composite film SnO2/石墨烯复合薄膜的合成、表征及乙醇气敏性能

Sri Lankan Journal of Physics Pub Date : 2015-01-26 DOI: 10.4038/SLJP.V15I0.6345

M. Jayaweera, R.C.L. De Silva, I. Kottegoda, S. Rosa

{"title":"Synthesis, characterization and ethanol vapor sensing performance of SnO2/Graphene composite film","authors":"M. Jayaweera, R.C.L. De Silva, I. Kottegoda, S. Rosa","doi":"10.4038/SLJP.V15I0.6345","DOIUrl":"https://doi.org/10.4038/SLJP.V15I0.6345","url":null,"abstract":"High performing sensor consisting of SnO 2 /Gn nanocomposite was fabricated using a novel one-step in-situ sonochemical method. The reducing properties of SnCl 2 was used to reduce graphite oxide (GO) so that SnCl 2 could be transformed to SnO 2 on the basal plane of graphene. The combined characterizations including X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier Transformed Infra-Red spectroscopic data (FTIR) indicated the successful formation of SnO 2 /Gn composites. Current-voltage (I-V) characteristics of the gas sensor showed ideal ohmic behavior having low resistance. To demonstrate the product on sensing application, gas sensors were fabricated using SnO 2 /Gn composites and used in detecting ethanol vapor at room temperature (27°C).The results indicate that the SnO 2 /Gn composite exhibits a considerably high sensing performance of 17.54% response at 150 ppm ethanol vapor, rapid response and reproducibility. Furthermore, the performance of the gas sensor based on SnO 2 /Gn is very stable for a long period of time under normal operating conditions. Therefore, it is suggested that SnO 2 /Gn can be considered as an excellent sensing material which also has a potential for wider range of applications on sensors.","PeriodicalId":21880,"journal":{"name":"Sri Lankan Journal of Physics","volume":"65 1","pages":"1"},"PeriodicalIF":0.0,"publicationDate":"2015-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90257776","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}

引用次数: 11

Simultaneous analysis of non-strange negative parity baryon Properties in large Nc QCD 大型Nc QCD中非奇异负宇称重子性质的同时分析

Sri Lankan Journal of Physics Pub Date : 2013-04-21 DOI: 10.4038/SLJP.V13I2.5443

S. Premaratne, C. Jayalath

引用次数: 0

Fractal Nature of Simulated Lightning Channels 模拟闪电通道的分形性质

Sri Lankan Journal of Physics Pub Date : 2013-04-19 DOI: 10.4038/SLJP.V13I2.5433

M.M.N. Perera, D. Sonnadara

{"title":"Fractal Nature of Simulated Lightning Channels","authors":"M.M.N. Perera, D. Sonnadara","doi":"10.4038/SLJP.V13I2.5433","DOIUrl":"https://doi.org/10.4038/SLJP.V13I2.5433","url":null,"abstract":"Cloud-to-ground lightning discharges in 2D and 3D domains were simulated using a stochastic dielectric breakdown model. The dependency between fractal dimension of the discharge patterns and the power of the local electric field η was critically evaluated. An exponential decrease in fractal dimension was observed as η increases. Fractal dimension of simulated 3D discharge patterns and 2D images of lightning discharges were compared by taking projections of simulated patterns. Discharge patterns similar to actual lightning were obtained when η ≈ 5.2. Influence of ground objects on simulated lightning discharges was also studied by introducing additional boundary conditions to the ground plane. It was observed that pointed structures on the ground have a higher probability of attracting simulated lightning discharges. An extension was introduced to dielectric breakdown model to simulate the development of upward connecting positive leader discharges that occur during the decent of a downward moving negative leader. It was found that the height of the stepped leader tip above the ground (at the time when the upward connecting leader initiation occurs) is dependent on the initial breakdown voltage threshold. The height of the point of interception was found to decrease exponentially as the breakdown threshold is increased. DOI: http://dx.doi.org/10.4038/sljp.v13i2.5433 Sri Lankan Journal of Physics, Vol. 13 ( 2 ) ( 2012 ) 09 - 25","PeriodicalId":21880,"journal":{"name":"Sri Lankan Journal of Physics","volume":"29 1","pages":"9"},"PeriodicalIF":0.0,"publicationDate":"2013-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82297263","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}

引用次数: 10

A model for Thundercloud Charge Separation 雷云电荷分离模型

Sri Lankan Journal of Physics Pub Date : 2013-04-19 DOI: 10.4038/SLJP.V13I2.5432

K. Tennakone, P. Hewageegana

引用次数: 0

Polarizability of a metallic nanosphere: Local random-phase approximation (LRPA) 金属纳米球的极化率:局部随机相近似(LRPA)

Sri Lankan Journal of Physics Pub Date : 2012-07-19 DOI: 10.4038/SLJP.V13I1.4211

P. Hewageegana

引用次数: 0

Transformation of Surface Charge Density in Mixed Number Lorentz Transformation 混合数洛伦兹变换中表面电荷密度的变换

Sri Lankan Journal of Physics Pub Date : 2012-07-19 DOI: 10.4038/SLJP.V13I1.3546

S. Rafiq, M. S. Alam

引用次数: 2

Gross Alpha and Gross Beta Activities of Tap Water Samples from Different Locations of Dhaka City 达喀市不同地点自来水样本的总α和总β活性

Sri Lankan Journal of Physics Pub Date : 2012-07-19 DOI: 10.4038/SLJP.V13I1.3917

M. Ferdous, M. Rahman, A. Begum

{"title":"Gross Alpha and Gross Beta Activities of Tap Water Samples from Different Locations of Dhaka City","authors":"M. Ferdous, M. Rahman, A. Begum","doi":"10.4038/SLJP.V13I1.3917","DOIUrl":"https://doi.org/10.4038/SLJP.V13I1.3917","url":null,"abstract":"Gross alpha and gross beta activities were determined for twenty tap water samples collected from different locations in Dhaka city. The instrumentations used to count the gross alpha and gross beta activities were ZnS scintillation detector and gas proportional counter, respectively. Concentrations ranging from 1.88 ± 0.03 mBq / l to 8.16 ± 0.03 mBq / l with an average 3.76 ± 1.50 mBq / l and from 29.305 ± 0.06 mBq/ l to 115.74 ± 0.16 mBq / l with an average 60.41 ± 23.57 mBq /l were observed for the gross alpha and gross beta activities, respectively. The results showed that the natural activities of alpha and beta emitting radionuclides in tap water samples did not exceed WHO recommended levels and were comparable with the data available in other parts of the world. It suggests that the radioactivity in tap water for the people residing in Dhaka city is not yet a problem. To ensure the safe level of radioactivity in drinking water, however, periodic monitoring of water quality for compliance is necessary. DOI: http://dx.doi.org/10.4038/sljp.v13i1.3917 Keywords: Gross Alpha; Gross beta; Tap water; ZnS Scintillation Counter and Gas Proportional Counter Sri Lankan Journal of Physics, Vol. 13(1) (2012) 01-08","PeriodicalId":21880,"journal":{"name":"Sri Lankan Journal of Physics","volume":"24 1","pages":"1"},"PeriodicalIF":0.0,"publicationDate":"2012-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86575555","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}

引用次数: 18

Bound state solutions of the Klein - Gordon equation for deformed Hulthen potential with position dependent mass 具有位置依赖质量的变形Hulthen势的Klein - Gordon方程的束缚态解

Sri Lankan Journal of Physics Pub Date : 2012-07-19 DOI: 10.4038/SLJP.V13I1.3780

A. Antia, A. Ikot, E. Ituen, I. Akpan

引用次数: 8