Pub Date : 2014-01-01DOI: 10.18488/journal.75/2014.1.2/75.2.42.47
E. Parham, A. Mokhtari
Ab initio density functional theory (DFT) has been used to investigate the thermal properties of the CuBr0.5Cl0.5 alloys over a wide range of temperature. Using the quasiharmonic approximation (QHA) for the some physical quantities of interest such as heat capacity at constant volume and entropy are calculated and discussed. The theoretical results show good agreement with the available experimental data for CuBr and CuCl. The present results show that symmetric and asymmetric structure of CuBr0.5Cl0.5 have a good agreement with the calculatingly value for heat capacity.
{"title":"Thermodynamics Properties of Copper Halide Alloy (CuBr0.5Cl0.5)","authors":"E. Parham, A. Mokhtari","doi":"10.18488/journal.75/2014.1.2/75.2.42.47","DOIUrl":"https://doi.org/10.18488/journal.75/2014.1.2/75.2.42.47","url":null,"abstract":"Ab initio density functional theory (DFT) has been used to investigate the thermal properties of the CuBr0.5Cl0.5 alloys over a wide range of temperature. Using the quasiharmonic approximation (QHA) for the some physical quantities of interest such as heat capacity at constant volume and entropy are calculated and discussed. The theoretical results show good agreement with the available experimental data for CuBr and CuCl. The present results show that symmetric and asymmetric structure of CuBr0.5Cl0.5 have a good agreement with the calculatingly value for heat capacity.","PeriodicalId":7386,"journal":{"name":"Advances in Physics Theories and Applications","volume":"53 1","pages":"42-47"},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85648143","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}
Pub Date : 2014-01-01DOI: 10.18488/JOURNAL.75/2014.1.1/75.1.1.8
A. Asiegbu, E. Echeweozo
A digital solar radiation measuring instrument has been designed, constructed and calibrated. It incorporates a small rectangular silicon photocell as the sensor. On exposure to solar radiation, electromotive force which is proportional to radiation intensity is developed within the circuit. The device correlates voltage developed with available solar intensity. A standard solarimeter was therefore used to calibrate the device to translate the unit of its reading from Volt to Watt per square meter. Intensity spread obtained with respect to time of day agrees with various studies conducted previously on tropical environments. Results obtained generally conform with those obtained by Medugu, et al. [1] and Chiemeka [2]). With a calibration conversion factor of 877.19(V – 1.71) Wm-2, the device can be used to collect reliable irradiace data which are both comparable and compatible with that of a standard solarimeter.
{"title":"DESIGN, CONSTRUCTION AND CALIBRATION OF A SOLAR RADIATION MEASURING METER","authors":"A. Asiegbu, E. Echeweozo","doi":"10.18488/JOURNAL.75/2014.1.1/75.1.1.8","DOIUrl":"https://doi.org/10.18488/JOURNAL.75/2014.1.1/75.1.1.8","url":null,"abstract":"A digital solar radiation measuring instrument has been designed, constructed and calibrated. It incorporates a small rectangular silicon photocell as the sensor. On exposure to solar radiation, electromotive force which is proportional to radiation intensity is developed within the circuit. The device correlates voltage developed with available solar intensity. A standard solarimeter was therefore used to calibrate the device to translate the unit of its reading from Volt to Watt per square meter. Intensity spread obtained with respect to time of day agrees with various studies conducted previously on tropical environments. Results obtained generally conform with those obtained by Medugu, et al. [1] and Chiemeka [2]). With a calibration conversion factor of 877.19(V – 1.71) Wm-2, the device can be used to collect reliable irradiace data which are both comparable and compatible with that of a standard solarimeter.","PeriodicalId":7386,"journal":{"name":"Advances in Physics Theories and Applications","volume":"74 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83988686","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}
Pub Date : 2014-01-01DOI: 10.18488/JOURNAL.75/2014.1.1/75.1.9.33
V. Mukhomorov
We give an overview of studies a bipolaron stability by variational method. For bipolaron formations, a relation is established between the variational principle and the virial theorem optimizing the electronic wave functions. We present a large number of qualitative and quantitative arguments, which indicate that the Landau-Pekar bipolaron is an axially-symmetrical formation. Much attention is paid to the analysis of the influence of the Coulomb electron-electron correlations on the stability of a large bipolaron. In detail we analyzed the criteria for determining the optimal wave functions. It is established that a step-by-step increase in the flexibility of the electronic wave function due to the electron correlations does not stabilize a one-center bipolaron. We show after into account of electron-electron correlations a singlet bipolaron retains spatial axially-symmetrical. At the same time, the electron-excited triplet states of Landau-Pekar bipolaron have spherical symmetry. The results of Kasirina and Lakhno are based on the one-center bipolaron model are incorrect. Presented evidence that the correct application of the variational method and correct account of electron-electron correlations only increase the binding energy of the bipolaron but symmetry of Hartree-Fock approximation can not change. We adduce proofs which point to methodological errors of one-center bipolaron model as well as arising from their calculations incorrect physical consequences. As illustrated in this review the axially symmetric Landau-Pekar bipolaron can correctly interpret the experimentally detected spectroscopic data.
{"title":"Landau-Pekar Bipolaron in Singlet and Triplet States","authors":"V. Mukhomorov","doi":"10.18488/JOURNAL.75/2014.1.1/75.1.9.33","DOIUrl":"https://doi.org/10.18488/JOURNAL.75/2014.1.1/75.1.9.33","url":null,"abstract":"We give an overview of studies a bipolaron stability by variational method. For bipolaron formations, a relation is established between the variational principle and the virial theorem optimizing the electronic wave functions. We present a large number of qualitative and quantitative arguments, which indicate that the Landau-Pekar bipolaron is an axially-symmetrical formation. Much attention is paid to the analysis of the influence of the Coulomb electron-electron correlations on the stability of a large bipolaron. In detail we analyzed the criteria for determining the optimal wave functions. It is established that a step-by-step increase in the flexibility of the electronic wave function due to the electron correlations does not stabilize a one-center bipolaron. We show after into account of electron-electron correlations a singlet bipolaron retains spatial axially-symmetrical. At the same time, the electron-excited triplet states of Landau-Pekar bipolaron have spherical symmetry. The results of Kasirina and Lakhno are based on the one-center bipolaron model are incorrect. Presented evidence that the correct application of the variational method and correct account of electron-electron correlations only increase the binding energy of the bipolaron but symmetry of Hartree-Fock approximation can not change. We adduce proofs which point to methodological errors of one-center bipolaron model as well as arising from their calculations incorrect physical consequences. As illustrated in this review the axially symmetric Landau-Pekar bipolaron can correctly interpret the experimentally detected spectroscopic data.","PeriodicalId":7386,"journal":{"name":"Advances in Physics Theories and Applications","volume":"63 1","pages":"9-33"},"PeriodicalIF":0.0,"publicationDate":"2014-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73963980","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}
The solution of Schrodinger equations for q-deformed modified Poschl-Teller and hyperbolic Scarf II potentials are investigated using Nikiforov-Uvarov method and a mapping method. By applying a translation of spatial variable non-deformed potentials are mapped on to deformed potential or vice versa and as a product the potential’s parameters scaling obtained. The bound state energy spectra obtained using NU method are given in the close form and the corresponding wave functions are formulated in terms of the Jacobi Polynomials. The energy spectra and the radial wave functions of the system are also produced by a mapping using potential’s parameters scaling from the non-deformed to the deformed potential. Keywords :Energy spectra, wave-function, q-deformed hyperbolic Scarf II, q-deformed modified Poschl-Teller, Nikiforov-Uvarov method, a mapping method DOI: 10.7176/APTA-16-8
利用Nikiforov-Uvarov方法和映射方法研究了q-变形修正Poschl-Teller势和双曲Scarf势的薛定谔方程的解。通过应用空间变量的平移，将非变形势映射到变形势上，反之亦然，并作为乘积获得势的参数缩放。给出了用NU法得到的束缚态能谱的封闭形式，并用雅可比多项式表示了相应的波函数。利用势的参数标度从非变形势到变形势进行映射，得到了系统的能谱和径向波函数。关键词:能谱，波函数，q-变形双曲Scarf II, q-变形修正Poschl-Teller, Nikiforov-Uvarov方法，映射方法DOI: 10.7176/ apata -16-8
{"title":"Energy Spectra and Wave Function Analysis of q-Deformed Modified Poschl-Teller and Hyperbolic Scarf II Potentials Using NU Method and a Mapping Method","authors":"A. Suparmi, C. Cari, H. Yuliani","doi":"10.7176/APTA-16-8","DOIUrl":"https://doi.org/10.7176/APTA-16-8","url":null,"abstract":"The solution of Schrodinger equations for q-deformed modified Poschl-Teller and hyperbolic Scarf II potentials are investigated using Nikiforov-Uvarov method and a mapping method. By applying a translation of spatial variable non-deformed potentials are mapped on to deformed potential or vice versa and as a product the potential’s parameters scaling obtained. The bound state energy spectra obtained using NU method are given in the close form and the corresponding wave functions are formulated in terms of the Jacobi Polynomials. The energy spectra and the radial wave functions of the system are also produced by a mapping using potential’s parameters scaling from the non-deformed to the deformed potential. Keywords :Energy spectra, wave-function, q-deformed hyperbolic Scarf II, q-deformed modified Poschl-Teller, Nikiforov-Uvarov method, a mapping method DOI: 10.7176/APTA-16-8","PeriodicalId":7386,"journal":{"name":"Advances in Physics Theories and Applications","volume":"1 1","pages":"64-74"},"PeriodicalIF":0.0,"publicationDate":"2013-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87594121","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}
In the evaluation of the reliability levels of electrical power systems, reliability indices play a vital role. These indicators are System Average Interruption Duration Index (SAIDI), System Average Interruption Frequency Index (SAIFI) and Customer Average Interruption Duration Index (CAIDI). Statistical analysis of reliability indices of Ikeja and Port-Harcourt distribution system was carried out in this research paper.. Ten years of outage data information from ten selected distribution feeders of Ikeja and Port-Harcourt distribution systems were used in this work. The mean and standard deviation of the basic reliability indices were computed using appropriate mathematical relations as input parameters. Olowu feeder of Ikeja distribution system recorded the highest mean SAIDI of 01040 compared to all other feeders in the selected distribution system. Customers on this feeder were interrupted for a prolonged time while fewer of the customers were adequately served. 7-UP feeder of Ikeja distribution system had the least mean SAIDI of 0.0693 because customers’ interruption was for a short period of time even though; more customers were being served by the feeder. Airport of Port-Harcourt distribution system recorded the highest mean SAIDI of 0.1050. More customers were interrupted compared to all other feeders on the distribution system while fewer of them were adequately served. Airport feeder of Port Harcourt distribution system had a least mean SAIFI of 0.1392 because fewer of the customers attached to this feeder were interrupted while many of them were adequately served. The result of the work will provide a background information for distribution system engineers for adequate planning and effective maintenance of Ikeja and Portharcourt distribution systems. Keywords: Statistical analysis, Mean SAIDI, Mean SAIFI, Mean CAIDI, SAIDI standard deviation, SAIFI standard deviation, CAIDI standard deviation . DOI : 10.7176/APTA/77-06 Publication date :May 31 st 2019
{"title":"Statistical Analysis of Reliability Indices of Ikeja and Port-Harcourt Distribution Systems","authors":"G. Ajenikoko, V. Nwagbara","doi":"10.7176/apta/77-06","DOIUrl":"https://doi.org/10.7176/apta/77-06","url":null,"abstract":"In the evaluation of the reliability levels of electrical power systems, reliability indices play a vital role. These indicators are System Average Interruption Duration Index (SAIDI), System Average Interruption Frequency Index (SAIFI) and Customer Average Interruption Duration Index (CAIDI). Statistical analysis of reliability indices of Ikeja and Port-Harcourt distribution system was carried out in this research paper.. Ten years of outage data information from ten selected distribution feeders of Ikeja and Port-Harcourt distribution systems were used in this work. The mean and standard deviation of the basic reliability indices were computed using appropriate mathematical relations as input parameters. Olowu feeder of Ikeja distribution system recorded the highest mean SAIDI of 01040 compared to all other feeders in the selected distribution system. Customers on this feeder were interrupted for a prolonged time while fewer of the customers were adequately served. 7-UP feeder of Ikeja distribution system had the least mean SAIDI of 0.0693 because customers’ interruption was for a short period of time even though; more customers were being served by the feeder. Airport of Port-Harcourt distribution system recorded the highest mean SAIDI of 0.1050. More customers were interrupted compared to all other feeders on the distribution system while fewer of them were adequately served. Airport feeder of Port Harcourt distribution system had a least mean SAIFI of 0.1392 because fewer of the customers attached to this feeder were interrupted while many of them were adequately served. The result of the work will provide a background information for distribution system engineers for adequate planning and effective maintenance of Ikeja and Portharcourt distribution systems. Keywords: Statistical analysis, Mean SAIDI, Mean SAIFI, Mean CAIDI, SAIDI standard deviation, SAIFI standard deviation, CAIDI standard deviation . DOI : 10.7176/APTA/77-06 Publication date :May 31 st 2019","PeriodicalId":7386,"journal":{"name":"Advances in Physics Theories and Applications","volume":"99 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81338778","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}
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