Pub Date : 2020-07-28DOI: 10.11648/j.ajmp.20200903.12
A. Nechayev
A new approach to the physical axiomatic of quantum mechanics is proposed. The basis of this approach is the rejection of the idea of an electron as a point particle. To describe the dynamics of the material substance of the electron, a new AMT (Action-Matter-Transfer) equation based on the Hamilton-Jacobi equation is proposed. This nonlinear equation simply transforms into the Schrodinger equation which becomes an intermediate step for solving a more general equation that describes the actual mass and charge density of an electron cloud. The dimensionless density of the material substance of the electron is equal to the square of the wave function. The nonlinearity of the AMT-equation make us question the validity of the quantum mechanical principle of superposition. The representation of an electron as a cloud with a distributed density helps to explain the interference effects in the well-known double-slit experiment. It is shown that light emission can occur in full accordance with classical electrodynamics when the material substance of an electron is spatially redistributed. Our approach makes it possible to interpret light as a chain of photons, each of which represents a “particle” of an electromagnetic wave propagating in space. The direction of radiation can be determined by the axis of rotation of the electron cloud due to the presence of the spin which turns the electron into elementary magnet, so the two electron clouds can form in an atom a stable structure of paired electrons in the form of two hemispheres rotating in one direction. In the framework of the quasi-classical concept of photon generation, the processes of reflection of light, its transmission through a transparent medium, and birefringence are discussed as well as Compton effect and laser emission.
{"title":"On the Semi-classical Approach to the Physical Axiomatic of Quantum Mechanics and the New Wave-Particle Interpretation of Light","authors":"A. Nechayev","doi":"10.11648/j.ajmp.20200903.12","DOIUrl":"https://doi.org/10.11648/j.ajmp.20200903.12","url":null,"abstract":"A new approach to the physical axiomatic of quantum mechanics is proposed. The basis of this approach is the rejection of the idea of an electron as a point particle. To describe the dynamics of the material substance of the electron, a new AMT (Action-Matter-Transfer) equation based on the Hamilton-Jacobi equation is proposed. This nonlinear equation simply transforms into the Schrodinger equation which becomes an intermediate step for solving a more general equation that describes the actual mass and charge density of an electron cloud. The dimensionless density of the material substance of the electron is equal to the square of the wave function. The nonlinearity of the AMT-equation make us question the validity of the quantum mechanical principle of superposition. The representation of an electron as a cloud with a distributed density helps to explain the interference effects in the well-known double-slit experiment. It is shown that light emission can occur in full accordance with classical electrodynamics when the material substance of an electron is spatially redistributed. Our approach makes it possible to interpret light as a chain of photons, each of which represents a “particle” of an electromagnetic wave propagating in space. The direction of radiation can be determined by the axis of rotation of the electron cloud due to the presence of the spin which turns the electron into elementary magnet, so the two electron clouds can form in an atom a stable structure of paired electrons in the form of two hemispheres rotating in one direction. In the framework of the quasi-classical concept of photon generation, the processes of reflection of light, its transmission through a transparent medium, and birefringence are discussed as well as Compton effect and laser emission.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"1 1","pages":"48"},"PeriodicalIF":0.0,"publicationDate":"2020-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76265049","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 : 2020-07-17DOI: 10.11648/j.ajmp.20200903.11
Fatou Dia, O. A. Niasse, B. Ba, Cheikh Sène
To compare the performance of PV modules, it was required to translate the measured I - V characteristics, to use certain standard conditions. The International Electrotechnical Committee (IEC) has defined the standard test condition (STC) for PV modules with 1000 W/m2 irradiance with AM 1.5 and 25°C module temperature. The IEC has also published some standard correction procedures (contained in IEC 60891) to translate irradiance and temperature values between different. IEC 60891 defines a procedure which helps to translate the measured I-V characteristics photovoltaic devices at standard test condition (STC). The IEC 60891 translation procedures can be applied only for the 20% variation in the irradiance, the irradiance should not be below 800 W/m2 for translation at STC but also for limit temperatures (35 ° VS). In our study we will use crystal technology and the temperature measurements carried out at the study site show temperatures varying from 55°C to 65°C. Data from tests in the wild has been converted to standard test conditions (STC) using four methods proposed by AJ Anderson and G. Blaesser, the combination method and the equations from international standard IEC 60891. These methods are compared using data from one year and the correlation between the measured data and the standardized data. The results demonstrated that the combination method has good precision in the STC conversion of the performance of the PV module under different climatic and technological conditions. Then, based on the investigation results of the conversion equations, these translation methods are distinguished by the type of solar cell technology and the field of application. There is a difference between in situ and natural tests, attributed to various factors but mainly to the mismatch between the spectral responses of the PV module and the reference solar cell. The combination method uses irradiance data and temperature and performance parameters under STC conditions of PV modules to predict the maximum output power. Therefore, it is essential to provide reliable weather data before designing photovoltaic power systems.
{"title":"Comparison of the Methods of Calculation of Measurements Standardization on the Outdoor Photovoltaic Modules","authors":"Fatou Dia, O. A. Niasse, B. Ba, Cheikh Sène","doi":"10.11648/j.ajmp.20200903.11","DOIUrl":"https://doi.org/10.11648/j.ajmp.20200903.11","url":null,"abstract":"To compare the performance of PV modules, it was required to translate the measured I - V characteristics, to use certain standard conditions. The International Electrotechnical Committee (IEC) has defined the standard test condition (STC) for PV modules with 1000 W/m2 irradiance with AM 1.5 and 25°C module temperature. The IEC has also published some standard correction procedures (contained in IEC 60891) to translate irradiance and temperature values between different. IEC 60891 defines a procedure which helps to translate the measured I-V characteristics photovoltaic devices at standard test condition (STC). The IEC 60891 translation procedures can be applied only for the 20% variation in the irradiance, the irradiance should not be below 800 W/m2 for translation at STC but also for limit temperatures (35 ° VS). In our study we will use crystal technology and the temperature measurements carried out at the study site show temperatures varying from 55°C to 65°C. Data from tests in the wild has been converted to standard test conditions (STC) using four methods proposed by AJ Anderson and G. Blaesser, the combination method and the equations from international standard IEC 60891. These methods are compared using data from one year and the correlation between the measured data and the standardized data. The results demonstrated that the combination method has good precision in the STC conversion of the performance of the PV module under different climatic and technological conditions. Then, based on the investigation results of the conversion equations, these translation methods are distinguished by the type of solar cell technology and the field of application. There is a difference between in situ and natural tests, attributed to various factors but mainly to the mismatch between the spectral responses of the PV module and the reference solar cell. The combination method uses irradiance data and temperature and performance parameters under STC conditions of PV modules to predict the maximum output power. Therefore, it is essential to provide reliable weather data before designing photovoltaic power systems.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"44 1","pages":"41"},"PeriodicalIF":0.0,"publicationDate":"2020-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86783517","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 : 2020-06-29DOI: 10.11648/j.ajmp.20200902.12
Yormahmad Kholov
Recent theoretical developments propose that gravity is emergent phenomenon. In line with this, in this paper, we show that gravitational and inertial properties of matter can be sufficiently explained by thermodynamics for a system consisting of material systems immersed in the quantum vacuum energy reservoir without reference to the microscopic constituencies of the quantum vacuum. The study focuses on the transfer of energy and matter in the interaction of material system with its vacuum surroundings and the relation of those to the system's macroscopic state variables and mechanical behavior of the system associated with forces acting on it. This analysis suggests that vacuum energy density about material systems is diminished and quantum vacuum energy density field takes on specific gradient there. Hence, gravity appears as effect of the change in the energy density of medium related with presence of another material object modifying vacuum surroundings and causing spontaneous motion of the system to minimize its energy driven by the second law. Whereas, inertia is explained to be an emergent thermodynamic effect of the change in the vacuum energy field about objects associated with the alteration of energy of systems itself due to the transfer of energy between systems to its surroundings. When those energy transfer operations do not comply with the second law of thermodynamic in terms of direction and rate of the energy flow, there will be generated resistance to the imposed changes known as inertial force. In such representation the equivalence principle finds unique definition revealing its origin.
{"title":"Thermodynamics of Moving Bodies or a New Approach to Emergent Gravity","authors":"Yormahmad Kholov","doi":"10.11648/j.ajmp.20200902.12","DOIUrl":"https://doi.org/10.11648/j.ajmp.20200902.12","url":null,"abstract":"Recent theoretical developments propose that gravity is emergent phenomenon. In line with this, in this paper, we show that gravitational and inertial properties of matter can be sufficiently explained by thermodynamics for a system consisting of material systems immersed in the quantum vacuum energy reservoir without reference to the microscopic constituencies of the quantum vacuum. The study focuses on the transfer of energy and matter in the interaction of material system with its vacuum surroundings and the relation of those to the system's macroscopic state variables and mechanical behavior of the system associated with forces acting on it. This analysis suggests that vacuum energy density about material systems is diminished and quantum vacuum energy density field takes on specific gradient there. Hence, gravity appears as effect of the change in the energy density of medium related with presence of another material object modifying vacuum surroundings and causing spontaneous motion of the system to minimize its energy driven by the second law. Whereas, inertia is explained to be an emergent thermodynamic effect of the change in the vacuum energy field about objects associated with the alteration of energy of systems itself due to the transfer of energy between systems to its surroundings. When those energy transfer operations do not comply with the second law of thermodynamic in terms of direction and rate of the energy flow, there will be generated resistance to the imposed changes known as inertial force. In such representation the equivalence principle finds unique definition revealing its origin.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"40 1","pages":"28"},"PeriodicalIF":0.0,"publicationDate":"2020-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89207449","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 : 2020-06-18DOI: 10.11648/j.ajmp.20200902.11
P. Pu, J. Pu, Zhengbin Zhu
A model for water (H2O) molecule, the structure of ice, snow and liquid water were presented, and the reasons of formation of their specific characteristics were modeled in good coincidence with observed data. (1) A stable quasi rigid molecule structure may be constructed by dominant trajectories of electrons round and between the H-O-H nucleus according with the laws of Columb’s force and Kepler’s movement rule. The core of the water molecule is a isosceles triangle with ratio of distances between nucleus: (H-H)2/(H-O)2=2.5, which would be surrounded by moving electrons and form an equilateral triangular pyramid (ETP Model) with 2 pairs of “+/-” electricity endpoints and edge length of 0.48017nm. (2) The “+/-” endpoint of a water molecule may attract other “-/+” endpoint in distance of less than 0.27 nm. A molecule may joints other molecule to have all their 4 planes parallel each other and the 6 molecules may joint as a hexagon loop with a common plane and then these loops may similarly be formed for each plane of the pyramid and extend to whole space and form the water ice structure with Zigzag Hexagon Tunnel-Vacancy System (ZHTVS Model) with porosity of ≥2.28. (3) A “sheet model” of desublimation like the snowflake is more possible phenomenon below 0°C in air, possessing the self-similarity with the hexagon-sexangle-six needle forms. (4) The liquid water has the same structure of the solid ice, but because there is 1/11 possibility to have an appearance of double electrons at one endpoint of the pyramid with “-” charge, so when the temperature is above 0°C, a part of water molecules on the frame may possess the energy for separating from the frame, and will move into the tunnel/vacancy, being as a “free water molecule”. The total volume of the liquid water would decrease until to 4°C to the minimum. The ratio of density of solid water ice and liquid water is 11/12=0.916667. (5) The relationships of the specific characteristics of the water with its construction, such as density, expansibility, compressibility, specific heat capacity, electric and thermal conductivity, solubility for O2, H2S, NaCl, KCl, etc. were discussed and numerical modeled. The experiments of saturated solution of NaCl audio-visual indicated that there are tunnel/vacancy spaces for storing NaCl molecules/ions, and increasing the volume of 1/11 of water volume after freezing. (6) The surface structure of liquid water and the applications of research results are presented in other papers.
{"title":"Study on the Structure Model of Water Molecule and the Reasons of Formation of Some Characteristics of Liquid & Solid Water","authors":"P. Pu, J. Pu, Zhengbin Zhu","doi":"10.11648/j.ajmp.20200902.11","DOIUrl":"https://doi.org/10.11648/j.ajmp.20200902.11","url":null,"abstract":"A model for water (H2O) molecule, the structure of ice, snow and liquid water were presented, and the reasons of formation of their specific characteristics were modeled in good coincidence with observed data. (1) A stable quasi rigid molecule structure may be constructed by dominant trajectories of electrons round and between the H-O-H nucleus according with the laws of Columb’s force and Kepler’s movement rule. The core of the water molecule is a isosceles triangle with ratio of distances between nucleus: (H-H)2/(H-O)2=2.5, which would be surrounded by moving electrons and form an equilateral triangular pyramid (ETP Model) with 2 pairs of “+/-” electricity endpoints and edge length of 0.48017nm. (2) The “+/-” endpoint of a water molecule may attract other “-/+” endpoint in distance of less than 0.27 nm. A molecule may joints other molecule to have all their 4 planes parallel each other and the 6 molecules may joint as a hexagon loop with a common plane and then these loops may similarly be formed for each plane of the pyramid and extend to whole space and form the water ice structure with Zigzag Hexagon Tunnel-Vacancy System (ZHTVS Model) with porosity of ≥2.28. (3) A “sheet model” of desublimation like the snowflake is more possible phenomenon below 0°C in air, possessing the self-similarity with the hexagon-sexangle-six needle forms. (4) The liquid water has the same structure of the solid ice, but because there is 1/11 possibility to have an appearance of double electrons at one endpoint of the pyramid with “-” charge, so when the temperature is above 0°C, a part of water molecules on the frame may possess the energy for separating from the frame, and will move into the tunnel/vacancy, being as a “free water molecule”. The total volume of the liquid water would decrease until to 4°C to the minimum. The ratio of density of solid water ice and liquid water is 11/12=0.916667. (5) The relationships of the specific characteristics of the water with its construction, such as density, expansibility, compressibility, specific heat capacity, electric and thermal conductivity, solubility for O2, H2S, NaCl, KCl, etc. were discussed and numerical modeled. The experiments of saturated solution of NaCl audio-visual indicated that there are tunnel/vacancy spaces for storing NaCl molecules/ions, and increasing the volume of 1/11 of water volume after freezing. (6) The surface structure of liquid water and the applications of research results are presented in other papers.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"57 1","pages":"11"},"PeriodicalIF":0.0,"publicationDate":"2020-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89381513","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 : 2020-05-29DOI: 10.11648/J.AJMP.20200901.12
Y. Chiang, Mikhail Olegovich Dzyuba
An oscillographic study of the Hall voltage with an unpolarized alternating current through a platinum sample revealed chiral features of the Hall effect, which clearly demonstrate the presence of the spin Hall effect in metals with a noticeable spin-orbit interaction. It was confirmed that, as in the case of direct current, the possibility of a spin-Hall effect is associated with the presence of an imbalance of the spins and charges at the edges of the samples, which is realized using their asymmetric geometry. In particular, it was found that such chiral features of the nonequilibrium spin-Hall effect (NSHE), such as independence from the direction of the injection current and the direction of the constant magnetic field, in the case of alternating current, make it possible to obtain a double-frequency transverse voltage, which can be used as a platform for creating spintronics devices.
{"title":"Nonequilibrium Spin-Hall Detector with Alternating Current","authors":"Y. Chiang, Mikhail Olegovich Dzyuba","doi":"10.11648/J.AJMP.20200901.12","DOIUrl":"https://doi.org/10.11648/J.AJMP.20200901.12","url":null,"abstract":"An oscillographic study of the Hall voltage with an unpolarized alternating current through a platinum sample revealed chiral features of the Hall effect, which clearly demonstrate the presence of the spin Hall effect in metals with a noticeable spin-orbit interaction. It was confirmed that, as in the case of direct current, the possibility of a spin-Hall effect is associated with the presence of an imbalance of the spins and charges at the edges of the samples, which is realized using their asymmetric geometry. In particular, it was found that such chiral features of the nonequilibrium spin-Hall effect (NSHE), such as independence from the direction of the injection current and the direction of the constant magnetic field, in the case of alternating current, make it possible to obtain a double-frequency transverse voltage, which can be used as a platform for creating spintronics devices.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"27 1","pages":"7"},"PeriodicalIF":0.0,"publicationDate":"2020-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91146112","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 : 2020-01-18DOI: 10.11648/J.AJMP.20200901.11
Y. Gott, E. Yurchenko
The effect of L-H and H-L transitions on the tokamak-reactor operation is considered. Both initial modes are considered as quasi-equilibrium states with the same thermal energy for constant total toroidal currents. A method has been developed for quantification the change in neutron yield in a tokamak- reactor during these transitions occurring over times much shorter than the plasma energy confinement time. The method is based on the use of duality of solutions of the Grad-Shafranov equation. The arbitrary functions included in this equation were found as a result of approximation of the normalized plasma pressure profiles, presented versus on the radial flow coordinate obtained at the DIII-D facility. To calculate changes in neutron fluxes during L-H and back H-L transitions, we used these plasma pressure distributions for the ITER device parameters presented in Cartesian coordinates. A numerical calculation showed that in the back H-L transition, a large spike on the global neutron production is possible, which was previously discovered experimentally (ALCATOR-C-Mode, 2001). Since such an increase in neutron fluxes during tokamak-reactor ITER operation poses a serious threat to both the personnel and the facility itself, it is necessary to exclude the possibility of such transitions. Thus, it is necessary to develop such a reactor design that would make it possible to obtain a self-sustaining thermonuclear reaction in the L-mode operation.
{"title":"Effect of L-H and H-L Transitions on Tokamak-reactor Operation","authors":"Y. Gott, E. Yurchenko","doi":"10.11648/J.AJMP.20200901.11","DOIUrl":"https://doi.org/10.11648/J.AJMP.20200901.11","url":null,"abstract":"The effect of L-H and H-L transitions on the tokamak-reactor operation is considered. Both initial modes are considered as quasi-equilibrium states with the same thermal energy for constant total toroidal currents. A method has been developed for quantification the change in neutron yield in a tokamak- reactor during these transitions occurring over times much shorter than the plasma energy confinement time. The method is based on the use of duality of solutions of the Grad-Shafranov equation. The arbitrary functions included in this equation were found as a result of approximation of the normalized plasma pressure profiles, presented versus on the radial flow coordinate obtained at the DIII-D facility. To calculate changes in neutron fluxes during L-H and back H-L transitions, we used these plasma pressure distributions for the ITER device parameters presented in Cartesian coordinates. A numerical calculation showed that in the back H-L transition, a large spike on the global neutron production is possible, which was previously discovered experimentally (ALCATOR-C-Mode, 2001). Since such an increase in neutron fluxes during tokamak-reactor ITER operation poses a serious threat to both the personnel and the facility itself, it is necessary to exclude the possibility of such transitions. Thus, it is necessary to develop such a reactor design that would make it possible to obtain a self-sustaining thermonuclear reaction in the L-mode operation.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"12 1","pages":"1"},"PeriodicalIF":0.0,"publicationDate":"2020-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87748954","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 : 2019-10-21DOI: 10.11648/j.ajmp.20190805.11
Ruoshui Liu, Jun Liu, Lichen Wang, Xiang Yu, Chenhui Lv, Zhengrui Li, Yan Mi, Lifeng Liu, Shuli He
Magnetocaloric effect (MCE) technology is considered as one of the most important fundamental thermodynamic effects, and plays an important role in the refrigeration area for its high energy-efficiency and eco-friendly characteristics. Rear earth based low temperature magnetic refrigerant shows broad application prospect in the future. Low cost and high processability are so important to the application in the refrigeration machine. In this paper, pure phase TbFe2Al10 was prepared by arc melting and long-time annealing process. The magnetic properties and magnetocaloric effect (MCE) of the TbFe2Al10 compound were intensively studied. It was determined to be antiferromagnetic with the Neel temperature TN =18 K. Two metamagnetic transitions from antiferromagnetic (AFM) to ferrimagnetic (FIM) and ferrimagnetic to ferromagnetic (FM) state occurred at 5 K under a crucial applied magnetic field of 0.95 T and 1.89 T, respectively. Field variation generated a large MCE and no magnetic hysteresis loss was observed. The maximum values of magnetic entropy change (ΔS) were found to be -4.5 J/kg K and –6.7 J/kg K for the field changes of 0-5 T and 0-7 T, respectively. The large ΔS with no hysteresis loss as well as low proportion of rare earth (Tb) in crude materials make TbFe2Al10 a competitive candidate as low temperature magnetic refrigerant.
{"title":"Reversal Magnetocaloric Effect in the Antiferromagnetic TbFe2Al10 Compound","authors":"Ruoshui Liu, Jun Liu, Lichen Wang, Xiang Yu, Chenhui Lv, Zhengrui Li, Yan Mi, Lifeng Liu, Shuli He","doi":"10.11648/j.ajmp.20190805.11","DOIUrl":"https://doi.org/10.11648/j.ajmp.20190805.11","url":null,"abstract":"Magnetocaloric effect (MCE) technology is considered as one of the most important fundamental thermodynamic effects, and plays an important role in the refrigeration area for its high energy-efficiency and eco-friendly characteristics. Rear earth based low temperature magnetic refrigerant shows broad application prospect in the future. Low cost and high processability are so important to the application in the refrigeration machine. In this paper, pure phase TbFe2Al10 was prepared by arc melting and long-time annealing process. The magnetic properties and magnetocaloric effect (MCE) of the TbFe2Al10 compound were intensively studied. It was determined to be antiferromagnetic with the Neel temperature TN =18 K. Two metamagnetic transitions from antiferromagnetic (AFM) to ferrimagnetic (FIM) and ferrimagnetic to ferromagnetic (FM) state occurred at 5 K under a crucial applied magnetic field of 0.95 T and 1.89 T, respectively. Field variation generated a large MCE and no magnetic hysteresis loss was observed. The maximum values of magnetic entropy change (ΔS) were found to be -4.5 J/kg K and –6.7 J/kg K for the field changes of 0-5 T and 0-7 T, respectively. The large ΔS with no hysteresis loss as well as low proportion of rare earth (Tb) in crude materials make TbFe2Al10 a competitive candidate as low temperature magnetic refrigerant.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75862492","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 : 2019-10-15DOI: 10.11648/j.ajmp.20190804.12
S. Diallo, I. Faye, L. Gomis, M. Tall, I. Diédhiou
Variational calculations of the helium atom states are performed using highly compact 26-parameter correlated Hylleraas-type wave functions. These correlated wave functions used here yield an accurate expectation energy values for helium ground and two first excited states. A correlated wave function consists of a generalized exponential expansion in order to take care of the correlation effects due to N-corps interactions. The parameters introduced in our model are determined numerically by minimization of the total atomic energy of each electronic configuration. We have calculated all integrals analytically before dealing with numerical evaluation. The 1S2 11S and 1S2S 21, 3S states energies, charge distributions and scattering atomic form factors are reported. The present work shows high degree of accuracy even with relative number terms in the trial Hylleraas wave functions definition. The results presented here, indicate that the highly compact twenty-six variational parameters model will have the quantitative and qualitative applicability for the study of electronic correlation. The correlated wave functions are used to calculate the atomic form factor for the diffusion of electrons by the helium atom. The atomic form factor is evaluated as the Fourier transform of the electron density distribution of an atom or ion, which is calculated from theoretical correlated wave functions for free atoms. Finally, suggestions are made as to the way the atomic form factor of the helium atom may be approximated by a sum of Gaussians for efficiency use.
{"title":"Atomic Form Factor Calculations of S-states of Helium","authors":"S. Diallo, I. Faye, L. Gomis, M. Tall, I. Diédhiou","doi":"10.11648/j.ajmp.20190804.12","DOIUrl":"https://doi.org/10.11648/j.ajmp.20190804.12","url":null,"abstract":"Variational calculations of the helium atom states are performed using highly compact 26-parameter correlated Hylleraas-type wave functions. These correlated wave functions used here yield an accurate expectation energy values for helium ground and two first excited states. A correlated wave function consists of a generalized exponential expansion in order to take care of the correlation effects due to N-corps interactions. The parameters introduced in our model are determined numerically by minimization of the total atomic energy of each electronic configuration. We have calculated all integrals analytically before dealing with numerical evaluation. The 1S2 11S and 1S2S 21, 3S states energies, charge distributions and scattering atomic form factors are reported. The present work shows high degree of accuracy even with relative number terms in the trial Hylleraas wave functions definition. The results presented here, indicate that the highly compact twenty-six variational parameters model will have the quantitative and qualitative applicability for the study of electronic correlation. The correlated wave functions are used to calculate the atomic form factor for the diffusion of electrons by the helium atom. The atomic form factor is evaluated as the Fourier transform of the electron density distribution of an atom or ion, which is calculated from theoretical correlated wave functions for free atoms. Finally, suggestions are made as to the way the atomic form factor of the helium atom may be approximated by a sum of Gaussians for efficiency use.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"241 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74151502","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 : 2019-09-19DOI: 10.11648/J.AJMP.20190804.11
Yawovi Nougbléga, K. Kpode, K. N’wuitcha, M. Banna
The solar photovoltaic-thermal energy, it is a combination of Photovoltaic (PV) and solar thermal components integrated into one system and enables to generate electricity and heat simultaneously. The solar chimney can generate air flow through the living space of the building to provide cooling. Hence, there is a greater interest to study the mixed convection in the hybrid Photovoltaic-Thermal chimney integrated into buildings for natural room ventilation for thermal comfort. The thermal efficiency has been studied by analysing numerically the mixed convection in the hybrid photovoltaic-thermal chimney integrated into the building in the present paper. The stream fucntion-vorticity formulation with a finite difference numerical discretization solution scheme have been adopted. The system of algebraic governing equations is solved by Thomas algorithm method. The aim of the present paper is to study and to predict the dynamic fields and particularly of the mass flow rate of the air thermosiphon drawing in the hybrid Photovoltaic-Thermal chimney integrated into a building for passive cooling in the room. The effects of the governing parameters, particularly Grashof number (103 ≤ Gr ≤ 106), that depends of the solar radiation intensity in the region, the mass flow rate of the inlet fresh air (0.001 Kg.s-1 ≤ Dm ≤ 0.3Kg.s-1), the integrated chimney width on fluid flow and the heat transfer characteristics are studied in detail. Passive cooling and the electrical efficiency of the PV solar cells are increasing function of the intensity of the inlet air flow. Due to the possible reduction of cooling loads with the insertion of the photovoltaic cells plate into the chimney integrated into the building. The numerical simulation has been conducted to determine heat transfer, mass flow rate trough the chimney exit, solar cells PV efficiency and the effect of design parameters of the room and the integrated hybrid Photovoltaic-Thermal chimney to make the bioclimatic building energy autonomy. The outlet velocity, streamlines, isotherms, Nusselt number along the active walls, and the mass flow rate are plotted versus the above controlling parameters.
{"title":"Thermal Efficiency of a Hybrid Photovoltaic-thermal Chimney Integrated into a Building","authors":"Yawovi Nougbléga, K. Kpode, K. N’wuitcha, M. Banna","doi":"10.11648/J.AJMP.20190804.11","DOIUrl":"https://doi.org/10.11648/J.AJMP.20190804.11","url":null,"abstract":"The solar photovoltaic-thermal energy, it is a combination of Photovoltaic (PV) and solar thermal components integrated into one system and enables to generate electricity and heat simultaneously. The solar chimney can generate air flow through the living space of the building to provide cooling. Hence, there is a greater interest to study the mixed convection in the hybrid Photovoltaic-Thermal chimney integrated into buildings for natural room ventilation for thermal comfort. The thermal efficiency has been studied by analysing numerically the mixed convection in the hybrid photovoltaic-thermal chimney integrated into the building in the present paper. The stream fucntion-vorticity formulation with a finite difference numerical discretization solution scheme have been adopted. The system of algebraic governing equations is solved by Thomas algorithm method. The aim of the present paper is to study and to predict the dynamic fields and particularly of the mass flow rate of the air thermosiphon drawing in the hybrid Photovoltaic-Thermal chimney integrated into a building for passive cooling in the room. The effects of the governing parameters, particularly Grashof number (103 ≤ Gr ≤ 106), that depends of the solar radiation intensity in the region, the mass flow rate of the inlet fresh air (0.001 Kg.s-1 ≤ Dm ≤ 0.3Kg.s-1), the integrated chimney width on fluid flow and the heat transfer characteristics are studied in detail. Passive cooling and the electrical efficiency of the PV solar cells are increasing function of the intensity of the inlet air flow. Due to the possible reduction of cooling loads with the insertion of the photovoltaic cells plate into the chimney integrated into the building. The numerical simulation has been conducted to determine heat transfer, mass flow rate trough the chimney exit, solar cells PV efficiency and the effect of design parameters of the room and the integrated hybrid Photovoltaic-Thermal chimney to make the bioclimatic building energy autonomy. The outlet velocity, streamlines, isotherms, Nusselt number along the active walls, and the mass flow rate are plotted versus the above controlling parameters.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73885291","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 : 2019-08-23DOI: 10.11648/J.AJMP.20190803.11
Z. Yue
Using the sample cell designed by ourselves and the electrorheological (ER) samples, one of them is imported from USA (sample 1), the other one is made from tsinghua university (sample2), we perform a series experiments with these two ER samples, and observe some curious phenomena; such as the ultrasonic study on the longitudinal sound velocity in electrorheological (ER) suspensions reveals the existence of a serious shear instability at the critical value of applied voltages, the evidence retains the time of about a few milliseconds; moreover, the experiments on ER samples demonstrate that there is a saturation value for the ultrasonic attenuation when the applied voltages arrive a critical value Vc, which resemble to the cases of a lot of superconductors at the critical value of temperature Tc; In the experiments on the I-V characteristic of the two ER samples, we observe that an abrupt change in the I-V characteristics occurs at the critical value Vc of the applied voltages, furthermore, the I-V characteristic of either of the two ER samples is linear after the applied voltages overpass the critical value Vc, just as same as the I-V characteristic of metal conductors. Therefore, it is reasonable to suggest that this anomalous ultrasonic evidence we observed in the experiments corresponds to a structural phase transition from liquidlike phase to metal-solidlike phase in the electrorheological suspensions.
{"title":"Anomalous and Instable Ultrasonic Evidence for a Structural Phase Transition at the Critical Value Vc in Electrorheological Suspensions","authors":"Z. Yue","doi":"10.11648/J.AJMP.20190803.11","DOIUrl":"https://doi.org/10.11648/J.AJMP.20190803.11","url":null,"abstract":"Using the sample cell designed by ourselves and the electrorheological (ER) samples, one of them is imported from USA (sample 1), the other one is made from tsinghua university (sample2), we perform a series experiments with these two ER samples, and observe some curious phenomena; such as the ultrasonic study on the longitudinal sound velocity in electrorheological (ER) suspensions reveals the existence of a serious shear instability at the critical value of applied voltages, the evidence retains the time of about a few milliseconds; moreover, the experiments on ER samples demonstrate that there is a saturation value for the ultrasonic attenuation when the applied voltages arrive a critical value Vc, which resemble to the cases of a lot of superconductors at the critical value of temperature Tc; In the experiments on the I-V characteristic of the two ER samples, we observe that an abrupt change in the I-V characteristics occurs at the critical value Vc of the applied voltages, furthermore, the I-V characteristic of either of the two ER samples is linear after the applied voltages overpass the critical value Vc, just as same as the I-V characteristic of metal conductors. Therefore, it is reasonable to suggest that this anomalous ultrasonic evidence we observed in the experiments corresponds to a structural phase transition from liquidlike phase to metal-solidlike phase in the electrorheological suspensions.","PeriodicalId":7717,"journal":{"name":"American Journal of Modern Physics","volume":"63 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84133044","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：