Jordan Journal of Physics最新文献

{"title":"The Casimir Energy for Lorentz-Violating Scalar Field in Sphere","authors":"M. A. Valuyan","doi":"10.47011/15.3.9","DOIUrl":"https://doi.org/10.47011/15.3.9","url":null,"abstract":"Abstract: In the present article, the Casimir energy was computed for the massless and Lorentz-violating scalar field, confined in a sphere with Dirichlet and Neumann boundary conditions. In 3+1 space-time dimensions, four violated directions to break the Lorentz symmetry are likely, according to which we presented the Casimir energy regarding all possible directions for the Lorentz violation and discussed the pure contribution to the Lorentz violation in a language of graphs. In the details of the calculation, a simple method was developed based on the direct mode summation and the sum-over-modes were performed via the contour integration in a complex plane of eigenfrequencies. The obtained result for all cases of Lorentz symmetry breaking was consistent with the expected physical basis.\u0000\u0000Keywords: Casimir energy, Lorentz-violating sphere scalar field.\u0000\u0000PACS No: 11.10.z; 11.10.Gh; 11.25.Db; 11.15.Bt","PeriodicalId":42562,"journal":{"name":"Jordan Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41755048","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":"I-V Characteristics Modeling of the Carbon Nanotube Field Effect Transistor (CNTFET)","authors":"Siham Kattar, S. Khemissi","doi":"10.47011/15.3.6","DOIUrl":"https://doi.org/10.47011/15.3.6","url":null,"abstract":"Abstract: A simulation model of a zig-zag type (10.0) single-walled carbon-nanotube (SW-CNT) transistor based on virtual source (VS-CNTFET) approach is presented in this paper. This semi-empirical physics-based model allowed the study of current-voltage (I-V) characteristics of the transistor. Additionally, analytical modeling of reflection coefficient, electron mobility in the CNT with low and high electric field and parasitic resistances (Rs and Rd) were presented as well in this model. Then, the obtained I-V characteristics of this SW-CNTFET were explored and compared with literature data obtained experimentally. Results showed that this model was a different approach which is significant compared to the silicon model in terms of the carrier mobility, where µCNT = 104 cm2/Vs. Moreover, the impacts of some geometric parameters, such as CNT length and diameter as well as oxide permittivity on the I-V characteristics, were proved.\u0000\u0000Keywords: Carbon nanotube, Virtual source, CNTFET, Electron mobility, I-V characteristics.","PeriodicalId":42562,"journal":{"name":"Jordan Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42418292","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":"Electrical Power Improvement of Grid-tied Photovoltaic Solar System","authors":"","doi":"10.47011/15.3.7","DOIUrl":"https://doi.org/10.47011/15.3.7","url":null,"abstract":"Abstract: The method that is used to improve performance and electrical power is to use optical reflectors. Optical reflectors improve performance and electrical power, because they increase solar irradiation. CIGS is an acronym for Copper Indium Gallium Selenide. CIGS PV solar module is a second-generation thin-film technology. The system with which optical reflectors are attached is 5kWp. CIGS PV solar system is situated at Al-Mansour factory, Baghdad-Iraq (longitude 44.4°E, latitude 33.3°N and 41m above the sea level). This study improves electrical power, current, performance ratio and array efficiency. All these improvements are done by increasing solar radiance via utilizing optical reflectors (fabricated from aluminum metal). The current system is divided into two parts: improved (PV modules with optical reflectors) and reference part (PV modules without optical reflectors). At 12:00 PM, the largest values of the solar irradiance, electrical power and current for improved and reference PV modules are 1346.1 W/m2 and 981.5 W/m2, 2.308 kW and 1.712 kW,6.01 A and 4.44 A, respectively. At 7.30 AM and 5:00 PM, the largest values of performance ratio and array efficiency of 98% and 14.8%, respectively, are recorded, while the minimum values are at 12:00 pm of 91% and 92.5% and 13.8% and 14.1%, respectively. The largest values of the improved and reference PV module temperatures are 56°C and 50°C, respectively, at the ambient temperature of 21°C. At 7:30 AM, the lowest values of the electrical power, current, solar irradiance and temperatures for the improved and reference PV modules are recorded to be 0.276 kW and 0.267 kW, 0.68 A and 0.65 A, 142.67 W/m2 and 138.44 W/m2, 33°C and 34°C, respectively, at an ambient temperature of 16°C. The maximum increment percentages (gains) for power, current, solar irradiance and module temperatures resulting from using optical reflectors are 34.4%, 35.3%, 37.1% and 6°C, respectively. The current work was achieved under clear sky conditions. The mean increment throughout a day is 24.4%, which is a very good indication of economic feasibility.\u0000\u0000Keywords: PV solar system, Efficiency, Optical reflector, Grid-connected, CIGS.","PeriodicalId":42562,"journal":{"name":"Jordan Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42508891","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":"Mapping and Delineation of Hard Rock Aquifers in Parts of the South-western Nigeria Basement Complex Using Integrated Geophysical Techniques","authors":"A. A. Fatoyinbo, T. O. Lawal, A. Yussuf, O. Fawale","doi":"10.47011/15.3.4","DOIUrl":"https://doi.org/10.47011/15.3.4","url":null,"abstract":"Abstract: An integrated geophysical survey involving three different techniques; namely, VLF-EM, Seismic Refraction and Vertical Electrical Sounding (VES) has been carried out in parts of Eruwa, Ibarapa East LGA, Oyo State with a view of determining the structural characteristics of the subsurface geology and identifying suitable sites where viable borehole could be sited to reduce the problem associated with acute shortage of groundwater in the area. The area lies within the crystalline basement rock terrain of South-Western Nigeria and bounded by Latitude 7° 32' 59\"N and Longitude 3° 25' 59\"E. The VES results reveal that the area is made up of four major lithologic layers with the topmost layer being majorly laterites, the second layer being sandy clay, the third is weathered basement, while the fourth layer is fractured basement. The aquifer in the study area is mostly confined with curve responses of HA- and HKH-types. The 2-D pseudosection also showed that the fresh basement is very extensive laterally with undulating topography. The result of VLF-EM revealed high-amplitude anomalies. These anomalies are indicative of high conductive zones within the basement bedrock of the study area. The results of the seismic inversion reveals three lithologic layers; namely, the topmost layer / topsoil which is sandy (moderately loose) with an average velocity of 500 m/s, the middle layer can be sandy clay/laterite/caked clay with an average velocity of 1,149.33 m/s and the third layer can be said to be the beginning of the weathered/fresh basement with a velocity of 2,719 m/s. In conclusion, the three geophysical techniques have shown that the area is a hard-rock terrain with complicated geology with aquifers confined and the water bearing formation with low total longitudinal conductance.\u0000\u0000Keywords: Basement terrain, Granitic masses, Aquifer, Topography, Curve types.","PeriodicalId":42562,"journal":{"name":"Jordan Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43762153","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":"Enhancement of the Solar-Thermal Response of Flat-plate Collector Coated with a Heat-resistant Paint","authors":"Ruaa H. Jasim, Ahmed A. Al-Tabbakh","doi":"10.47011/15.3.10","DOIUrl":"https://doi.org/10.47011/15.3.10","url":null,"abstract":"Abstract: A commercially available heat-resistant paint (HRP) is used as the primary component of a composite coating for low-temperature flat collector system. The same is mixed with small amounts of carbon black powder (CBP), lithium metal oxide (LMO) powder or both in an attempt to enhance the coating solar-thermal conversion characteristics. The optical characteristics of these coatings are investigated by means of optical microscopy, optical spectrophotometry and measurement of reflectance. The solar-thermal conversion characteristics are investigated by measuring the maximum collector temperature due to exposure to solar radiation. Results show that the solar-thermal conversion (maximum temperature) of the collector plate can be improved with the addition of CBP and LMO particles at low concentrations. The solar-thermal characteristics of the coatings are reported and compared with those of different coatings. The coatings prepared in the present work can easily be applied on the collector surface, which makes them suitable for flat-plate collector systems.\u0000\u0000Keywords: Flat plat collector, Selective coating, Optical properties, Solar irradiance.","PeriodicalId":42562,"journal":{"name":"Jordan Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45365436","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":"Assessment of Radioactivity Levels in Soil of Koya District in Kurdistan Region-Iraq Using High-purity Germanium Detector","authors":"Dashty A. Babakr, Saddon T. Ahmad, Akram H. Taha","doi":"10.47011/15.3.5","DOIUrl":"https://doi.org/10.47011/15.3.5","url":null,"abstract":"Abstract: This study has been conducted to assess the 226Ra, 232Th, 40K and 137Cs radionuclides concentrations, through (5-10 and 15-25) cm-depth layers of the Koya district uncultivated soils, Erbil governorate, Kurdistan Region-Iraq, for 90 samples in 2018, using high-purity germanium detector (HpGe). As a result, the 5-10 cm layer concentrations have ranged from ‎3.8 ± 1.0 to 21.3 ± 0.3‎ (Bq.kg-1), 3‎.9 ± 0.3 to 36.2 ± 1.2 (Bq.kg-1), 95.0 ± 2.2 to 597.3 ± 8.9 (Bq.kg-1) and 0.0 to 42.7 ± 0.4 (Bq.kg-1) for 226Ra, 232Th‎, 40K and 137Cs, respectively. ‎In contrast, the 15-25 cm layer activities have shown lower values, where they have ranged from 2.6 ± 0.9 to 20.1 ± 0.3 (Bq.kg-1), 3.1 ± 0.3 to 35.3 ± 1.2 (Bq.kg-1), 545.0 ± 8.1 to 92.4 ± 2.1 (Bq.kg-1) and 0.0 to 29.1 ± 0.3 (Bq.kg-1), for 226Ra, 232Th‎, 40K and 137Cs, respectively. Moreover, the radiological parameters; namely, indoor and outdoor gamma absorbed dose rates, annual effective dose rates and excess life time cancer risks with internal and external hazard indices, have been estimated as follows: ‎(56.44, 29.22) ‎(nGy.h-1),) ‎0.28, ‎0.04) ‎‎(mSv.y-1)‎, ‎(0.97, 0.13) x 10-3, ‎0.20 and‎ 0.17, respectively. Fortunately, the results correspond with internationally healthy values.\u0000\u0000 Keywords: Radioactivity, Soil, Effective dose, HPGe, Hazard, Koya.","PeriodicalId":42562,"journal":{"name":"Jordan Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42636056","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":"Solutions of the Non-relativistic Equation Interacting with the Varshni-Hellmann Potential Model with Some Selected Diatomic Molecules","authors":"","doi":"10.47011/15.2.8","DOIUrl":"https://doi.org/10.47011/15.2.8","url":null,"abstract":"Abstract: The approximate solutions of Schrödinger equation for the newly proposed Varshni-Hellmann potential (VHP) are obtained within the framework of the Nikiforov-Uvarov method by employing the Greene-Aldrich approximation scheme to deal with the centrifugal term. The numerical results of the ro-vibrational energies and normalized wavefunction in closed form are obtained in terms of Jacobi polynomials for various quantum states of the diatomic molecules of respectively. Four special cases of the potential are also studied and their numerical energy eigenvalues evaluated are in agreement with those reported in the existing literature. Also, the behavior of the energy spectra for the ground state of the selected diatomic molecules is illustrated graphically.\u0000Keywords: Schrödinger equation; Varshni-Hellmann potential, Nikiforov-Uvarov method, Diatomic molecules.","PeriodicalId":42562,"journal":{"name":"Jordan Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42604993","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":"BALQARAD Geant4 Model: Enhancement in γ-ray Spectroscopy and Validation","authors":"","doi":"10.47011/15.2.5","DOIUrl":"https://doi.org/10.47011/15.2.5","url":null,"abstract":"Abstract: Advances in gamma-ray spectroscopy allow for excellent background suppression and increased efficiency using composite Clover detectors with combinations of active shields. The events from such combinations, registered in list mode and analyzed offline, promote significant sensitivity improvements for gamma detection. This study utilizes the modularity of such composite of high-purity germanium radiation detectors to investigate their applicability in different possible fields. A comprehensive survey is conducted on the appropriate radioactive isotope serving each application. According to its decay scheme, investigation on the proper modes of operation for each isotope is carried out by Monte Carlo simulation applied to the Clover detector geometry. Addback factor measurements were performed using the newly acquired BALQARAD Clover. In an offline analysis through self-developed software, the Clover direct and addback performances are deduced versus gamma-ray energy. Measurement results obtained using the Clover detectors agree reasonably well with those obtained by Monte Carlo simulation.\u0000Keywords: Geant4, HPGe, Clover-type detector, Detector modeling and simulation, Modes of operation, Addback factor.","PeriodicalId":42562,"journal":{"name":"Jordan Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47361653","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":"Raman Spectroscopy Investigation on Semi-curve Woven Fabric-graphene Synthesized by the Chemical Vapor Deposition Process","authors":"","doi":"10.47011/15.2.7","DOIUrl":"https://doi.org/10.47011/15.2.7","url":null,"abstract":"Abstract: Graphene is a single layer of two-dimensional carbon atoms bound in a hexagonal lattice structure with zero band gap semiconductor. Chemical vapor deposition (CVD) is one of the most promising, inexpensive and readily ways for synthesizing monolayer pristine graphene. We have synthesized monolayer graphene shaped in semi-curve woven frabic-graphene (SWF-G) on SiO2/Si substrate. Using Raman spectroscopy, we studied the central suspended portion (i.e., 1-6) of it exerting compression (stress) to the graphene supported on the substrate. The concentration of hole impurities on either side of the central position of semi-curve woven fabric-graphene (SWF-G) is more than on its central position. The variation of such hole doping concentration results in an upshift of 2D peak position (pos(2D)) which is opposite for high electron doping even if there is no intentional control of doping. The synthesized graphene is a single-layer high-quality new structure graphene.\u0000Keywords: Semi-curve woven fabric-graphene, Raman spectroscopy, Charge impurities, Compression, Doping.","PeriodicalId":42562,"journal":{"name":"Jordan Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44941777","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":"Eigensolution and Expectation Values of the Hulthen and Generalized Inverse Quadratic Yukawa Potential","authors":"P. O. Okoi, C. Edet, T. Magu, E. Inyang","doi":"10.47011/15.2.4","DOIUrl":"https://doi.org/10.47011/15.2.4","url":null,"abstract":"Abstract: In this study, the Schrödinger equation was solved with a superposition of the Hulthen potential and generalized inverse quadratic Yukawa potential model using the Nikiforov-Uvarov (NU) method. For completeness, we also calculated the wave function. To validate our results, the numerical bound state energy eigenvalues was computed for various principal n and angular momentum l quantum numbers. With the aid of the Hellmann-Feynman theorem, the expressions for the expectation values of the square of inverse of position, r^(-2), inverse of position, r^(-1), kinetic energy, T ̂ and square of momentum, p ̂ are calculated. By adjusting the potential parameters, special cases of the potential were considered, resulting in Generalized Inverse Quadratic Yukawa potential, Hulthen potential, Coulomb potential, Kratzer potential, Inversely Quadratic Yukawa potential and Coulomb plus inverse square potential, respectively. Their energy eigenvalue expressions and numerical computations agreed with the literature.\u0000Keywords: Schrödinger equation, Hulthen potential (HP), Generalized inverse quadratic Yukawa potential (GIQYP), Nikiforov-Uvarov method.\u0000PACS: 03.65.−w, 03.65.Ca, 03.65.Ge.","PeriodicalId":42562,"journal":{"name":"Jordan Journal of Physics","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41789482","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}